Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmen...Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmental gradients.Particularly,the relative importance(RIV)of different plant life forms in a community and how they vary with environmental variables are still unclear.To fill these gaps,we determined plant diversity of ephemeral plants,annual herbs,perennial herbs,and woody plants from 187 sites across drylands in China.The SR patterns of herbaceous plants,especially perennial herbs,and their RIV in plant communities increased with increasing precipitation and soil nutrient content;however,the RIV of annual herbs was not altered along these gradients.The SR and RIV of ephemeral plants were affected mainly by precipitation seasonality.The SR of woody plants had a unimodal relationship with air temperature and exhibited the highest RIV and SR percentage in plant communities under the harshest environments.An obvious shift emerged in plant community composition,SR and their critical impact factors at 238.5 mm of mean annual precipitation(MAP).In mesic regions(>238.5 mm),herbs were the dominant species,and the SR displayed a relatively slow decreasing rate with increasing aridity,which was mediated mainly by MAP and soil nutrients.In arid regions(<238.5 mm),woody plants were the dominant species,and the SR displayed a relatively fast decreasing rate with increasing aridity,which was mediated mainly by climate variables,especially precipitation.Our findings highlight the importance of comparative life form studies in community structure and biodiversity,as their responses to gradients differed substantially on a large scale.展开更多
Biotechnology has revolutionized agriculture through innovations such as genetically modified(GM)technology and CRISPR/Cas9 genome editing.In this review,a comparative analysis of these methods that addresses the conc...Biotechnology has revolutionized agriculture through innovations such as genetically modified(GM)technology and CRISPR/Cas9 genome editing.In this review,a comparative analysis of these methods that addresses the concerns regarding the oversimplification of the notion that the CRISPR-based editing approach is equivalent to traditional GM approaches is offered.Since the 1990s,despite the potential benefits for crop improvement and food security,controversies have arisen around recombinant technology and the introduction of GM products due to perceived environmental and health concerns.In contrast,the recent emergence of the CRISPR/Cas systemas a precise genome editing tool has garnered relatively less public resistance.In this review,the reasons for these contrasting findings are explored to shed light on the distinct characteristics inherent to each approach.Additionally,we conduct a bibliographic analysis to examine the shift in research priorities between the two technological eras,followed by a comprehensive comparison of the two approaches,to enable a better understanding of the potential synergies that can be achieved between agricultural biotechnology and conventional techniques for enhancing modern agriculture.A nuanced understanding of these technologies is crucial for informed decision-making,responsible implementation,and addressing the concerns surrounding agricultural biotechnology.展开更多
Today, most people know that physical activity(PA) is beneficial for their health ^(1,2)and aspire to engage in regular PA.^(3,4)However, despite their awareness of the importance of PA, it is evident that the transit...Today, most people know that physical activity(PA) is beneficial for their health ^(1,2)and aspire to engage in regular PA.^(3,4)However, despite their awareness of the importance of PA, it is evident that the transition from intention to action is challenging-a situation that has important public health implications. According to the World Health Organization,^(5)1 person dies every 6 s worldwide from causes related to physical inactivity, which underscores the urgency of addressing this situation.展开更多
In this study,we investigated how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest communities.In the oldest ...In this study,we investigated how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest communities.In the oldest pure communi-ties of Pinus nigra(PN),Fagus orientalis(FO),and Abies bornmuelleriana(AB)in the mountain range of Mount Uludağ,Bursa,Turkey,annual net yield and N mineraliza-tion in the 0-5-and 5-20-cm soil layers were determined in a field incubation study over 1 year.Sampling locations were chosen from 1300 to 1600 m a.s.l.,and moisture content(%),pH,water-holding capacity(%),organic C,total N,and C/N ratio,and annual net mineral N yield of the soil and hydro-lyzed tannic acid and total phenolic compounds in litter were compared for these forest communities.F.orientalis had the highest annual net Nmin yield(43.9±4.8 kg ha^(-1) a^(-1)),P.nigra the lowest(30.5±4.2 kg ha^(-1) a^(-1)).Our findings show that in the oldest forest ecosystems,the seasonal soil moisture content and tree species play an essential role in N cycling and that hydrolyzed tannic acids and total phenolic compounds effectively control N turnover.Tannic acid and total phenolics in the litter were found to inhibit nitrification,but total phenolics were found to stimulate ammonification.展开更多
The Arctic,an essential ecosystem on Earth,is subject to pronounced anthropogenic pressures,most notable being the climate change and risks of crude oil pollution.As crucial elements of Arctic environments,benthic mic...The Arctic,an essential ecosystem on Earth,is subject to pronounced anthropogenic pressures,most notable being the climate change and risks of crude oil pollution.As crucial elements of Arctic environments,benthic microbiomes are involved in climate-relevant biogeochemical cycles and hold the potential to remediate upcoming contamination.Yet,the Arctic benthic microbiomes are among the least explored biomes on the planet.Here we combined geochemical analyses,incubation experiments,and microbial community profiling to detail the biogeography and biodegradation potential of Arctic sedimentary microbiomes in the northern Barents Sea.The results revealed a predominance of bacterial and archaea phyla typically found in the deep marine biosphere,such as Chloroflexi,Atribacteria,and Bathyarcheaota.The topmost benthic communities were spatially structured by sedimentary organic carbon,lacking a clear distinction among geographic regions.With increasing sediment depth,the community structure exhibited stratigraphic variability that could be correlated to redox geochemistry of sediments.The benthic microbiomes harbored multiple taxa capable of oxidizing hydrocarbons using aerobic and anaerobic pathways.Incubation of surface sediments with crude oil led to proliferation of several genera from the so-called rare biosphere.These include Alkalimarinus and Halioglobus,previously unrecognized as hydrocarbon-degrading genera,both harboring the full genetic potential for aerobic alkane oxidation.These findings increase our understanding of the taxonomic inventory and functional potential of unstudied benthic microbiomes in the Arctic.展开更多
Glucose is the primary fuel source of the brain,and therefore glucose levels need to be tightly regulated and maintained within a small physiological range.Certainly,the body necessitates a stable supply of energy mai...Glucose is the primary fuel source of the brain,and therefore glucose levels need to be tightly regulated and maintained within a small physiological range.Certainly,the body necessitates a stable supply of energy mainly provided by glucose for various bodily functions.High or low blood glucose levels would impair the physiological functions of various organs of the body.展开更多
Aim： To perform screening, related to A-kinase anchoring proteins 4 （AKAP4） and tubulin proteins, in spermatozoa with absent or severely reduced motility in order to detect the status of the fibrous sheath and the ...Aim： To perform screening, related to A-kinase anchoring proteins 4 （AKAP4） and tubulin proteins, in spermatozoa with absent or severely reduced motility in order to detect the status of the fibrous sheath and the axonemal structure. Methods： An immunocytochemical study of tubulin, used as a positive control, and AKAP4 was carded out to detect the presence and the distribution of these proteins in different sperm samples. The morphological characteristics of sperm were studied by transmission electron microscope （TEM） and the results were elaborated using a formula reported in previous studies. PCR was carried out on DNA extracted from peripheral blood lymphocytes to analyse partial sequences of the Akap4 and Akap3 genes. Results： Immunolabelling of tubulin and AKAP4 showed different patterns, which led us to divide the patients into groups. In group I, the absence of AKAP4 and tubulin was revealed, although these patients did not show alterations in the Akap4/Akap3 binding site. TEM evaluation highlighted that a high presence of necrosis was associated with total sperm immotility. In group Ⅱ, a regular AKAP4 and tubulin signal was present, although motility was reduced and TEM analysis revealed the presence of immaturity. In group Ⅲ, in which a weak AKAP4 label associated with normal tubulin staining and reduced motility was observed, a severe disorganization of the fibrous sheath was highlighted by TEM. Conclusion： While the role of AKAP4 in sperm motility is unclear, absent or weak AKAP4-1abelling seems to be associated with absent or weak sperm motility.展开更多
Low availability of phosphorus(P) is a major constraint for optimal crop production, as P is mostly present in its insoluble form in soil. Therefore,phosphate-solubilizing bacteria(PSB) from paddy field soils of the I...Low availability of phosphorus(P) is a major constraint for optimal crop production, as P is mostly present in its insoluble form in soil. Therefore,phosphate-solubilizing bacteria(PSB) from paddy field soils of the Indo-Gangetic Plain, India were isolated, and their abundance was attempted to be correlated with the physicochemical characteristics of the soils. Ninety-four PSB were isolated on Pikovskaya’s agar medium, and quantitative phosphate solubilization was evaluated using NBRIP medium. The isolates solubilized P up to a concentration of 1 006 μg mL-1 from tricalcium phosphate with the secretion of organic acids. These isolates were identified by 16 S rRNA gene sequence comparison, and they belonged to Gammaproteobacteria(56 isolates),Firmicutes(28 isolates), Actinobacteria(8 isolates), and Alphaproteobacteria(2 isolates). Phylogenetic analysis confirmed the identification by clustering the isolates in the clade of the respective reference organisms. The correlation analysis between PSB abundance and physicochemical characteristics revealed that the PSB population increased with increasing levels of soil organic carbon, insoluble P, K+, and Mg2+. The promising PSB explored in this study can be further evaluated for their biofertilizer potential in the field and for their use as potent bio-inoculants.展开更多
Aim： To study the immune-modulating and anti-oxidant effects of beta-glucan, papaya, lactoferrin, and vitamins C and E on sperm characteristics of patients with asthenoteratozoospermia associated with leucocytosis. M...Aim： To study the immune-modulating and anti-oxidant effects of beta-glucan, papaya, lactoferrin, and vitamins C and E on sperm characteristics of patients with asthenoteratozoospermia associated with leucocytosis. Methods： Fifty-one patients referred to our Sterility Center for semen analysis were selected. Sperm parameters were assessed before and after patient＇s treatment with beta-glucan, lactoferrin, papaya, and vitamins C and E. DNA damage was assessed by the acridine orange test and sperm structural characteristics were evaluated by transmission electron microscopy. Results： After 90 days of treatment, an increase in the percentage of morphologically normal sperm （17.0 ± 5.2 vs. 29.8 ± 6.5） and total progressive motility （19.0± 7.8 vs. 34.8 ± 6.8） were detected. Structural sperm characteristics as well as chromatin integrity were also improved after treatment. In terms of leukocyte concentration in seminal fluid, a significant reduction was recorded （2.2 ± 0.9 vs. 0.9± 0.2）. Conclusion： The treatment of an inflammatory process by the synergic action of immune modulators and anti-oxidants could protect sperm during maturation and migration, leading to improved sperm function. （Asian JAndrol 2008 Mar;. 10： 201-206）展开更多
Erythropoietin is essential for bone marrow erythropoiesis and erythropoietin receptor on non-erythroid cells including bone marrow stromal cells suggests systemic effects of erythropoietin. Tg6 mice with chronic eryt...Erythropoietin is essential for bone marrow erythropoiesis and erythropoietin receptor on non-erythroid cells including bone marrow stromal cells suggests systemic effects of erythropoietin. Tg6 mice with chronic erythropoietin overexpression have a high hematocrit, reduced trabecular and cortical bone and bone marrow adipocytes, and decreased bone morphogenic protein 2 driven ectopic bone and adipocyte formation. Erythropoietin treatment(1 200 IU·kg–1) for 10 days similarly exhibit increased hematocrit,reduced bone and bone marrow adipocytes without increased osteoclasts, and reduced bone morphogenic protein signaling in the bone marrow. Interestingly, endogenous erythropoietin is required for normal differentiation of bone marrow stromal cells to osteoblasts and bone marrow adipocytes.ΔEpoR_E mice with erythroid restricted erythropoietin receptor exhibit reduced trabecular bone, increased bone marrow adipocytes, and decreased bone morphogenic protein 2 ectopic bone formation. Erythropoietin treated ΔEpoR_E mice achieved hematocrit similar to wild-type mice without reduced bone, suggesting that bone reduction with erythropoietin treatment is associated with non-erythropoietic erythropoietin response. Bone marrow stromal cells from wild-type,Tg6, and ΔEpoR_E-mice were transplanted into immunodeficient mice to assess development into a bone/marrow organ. Like endogenous bone formation, Tg6 bone marrow cells exhibited reduced differentiation to bone and adipocytes indicating that high erythropoietin inhibits osteogenesis and adipogenesis, while ΔEpoR_E bone marrow cells formed ectopic bones with reduced trabecular regions and increased adipocytes, indicating that loss of erythropoietin signaling favors adipogenesis at the expense of osteogenesis. In summary, endogenous erythropoietin signaling regulates bone marrow stromal cell fate and aberrant erythropoietin levels result in their impaired differentiation.展开更多
We analysed ejaculated spermatozoa from five infertile men with different balanced reciprocal translocations to contribute to the study of meiotic segregation of chromosomes 18, X and Y and also to evaluate sperm morp...We analysed ejaculated spermatozoa from five infertile men with different balanced reciprocal translocations to contribute to the study of meiotic segregation of chromosomes 18, X and Y and also to evaluate sperm morphology by transmission electron microscopy （TEM） analysis. Conventional lymphocyte karyotype analyses highlighted dif- ferent reciprocal balanced translocations： t（12; 13）, t（4;9）, t（X;8）, t（8; 10） and t（3; 16）. Semen analysis was performed by light and TEM. Fluorescence in situ hybridization was performed directly on sperm nuclei using centromeric probes for chromosomes 18, X and Y. The carriers of the balanced reciprocal translocations considered in the present study showed a very similar pattern of sperm pathologies： diffused presence of apoptosis and immaturity. All patients showed meiotic segregation derangements, highlighted by the presence of sperm diploidies and sex chromosome disomies particularly related to the failure of the first meiotic division. However, an increased incidence of chromosome 18 aneuploidy was detected in spermatozoa from t（X;8） and t（8;10） carriers. We have also reported values from sex chromosomes such as t（X;8）, although the X chromosome was involved in translocation. Since patients with reciprocal translocations and spermatogenetic impairment are candidates for intracytoplasmic sperm injection cycles, the study of sperm parameters, and particularly of the level of aneuploidy rates, would provide better information for couples at risk and would contribute to the data in the literature for a better understanding of the effects of chromosomal rearrangement on the whole meiotic process and, in particular, on chromosomes not involved in translocation.展开更多
RNA granules are cytoplasmic, microscopically visible, non-membrane ribo-nucleoprotein structures and are important posttranscriptional regulators in gene expression by controlling RNA translation and stability. TIA/G...RNA granules are cytoplasmic, microscopically visible, non-membrane ribo-nucleoprotein structures and are important posttranscriptional regulators in gene expression by controlling RNA translation and stability. TIA/G3BP/PABP-specific stress granules(SG) and GW182/DCP-specific RNA processing bodies(PB) are two major distinguishable RNA granules in somatic cells and contain various ribosomal subunits, translation factors, scaffold proteins, RNA-binding proteins, RNA decay enzymes and helicases to exclude m RNAs from the cellular active translational pool. Although SG formation is inducible due to cellular stress, PB exist physiologically in every cell. Both RNA granules are important components of the host antiviral defense. Virus infection imposes stress on host cells and thus induces SG formation. However, both RNA and DNA viruses must confront the hostile environment of host innate immunity and apply various strategies to block the formation of SG and PB for their effective infection and multiplication. This review summarizes the current research development in the field and the mechanisms of how individual viruses suppress the formation of host SG and PB for virus production.展开更多
AIM: To study the efficacy of tenofovir disoproxil fumarate (TDF) at low dose in a small open trial of chronic hepatitis B patients with advanced stage disease. METHODS: Eleven patients were treated with TDF 75 mg for...AIM: To study the efficacy of tenofovir disoproxil fumarate (TDF) at low dose in a small open trial of chronic hepatitis B patients with advanced stage disease. METHODS: Eleven patients were treated with TDF 75 mg for a median period of 80 (range, 24-576) wk and then 7 cases were shifted to an adefovir 10 mg treatment group. All patients had been pre-treated with lamivudine: 5 had YMDD resistant mutants and 6 wild- type virus. When TDF was started, 4 patients had low- level viremia and 6 were PCR-negative. RESULTS: During TDF treatment, PCR remained negative in 10 patients, transaminase levels were normal and no significant viral breakthrough was observed. The drug was well tolerated in all cases. When TDF 75 mg was substituted with adefovir 10 mg, 3 out of 7 patients had a persistent viral rebound (2700-130 000 copies/mL), in whom lamivudine had to be reintroduced. CONCLUSION: Low-dose TDF monotherapy can control HBV viremia for an extended period of time without the emergence of resistance and is more potent than adefovir at the standard dosage. The use of a reduced dose of TDF could diminish the cost of therapy in low-income countries, but further studies in a larger population and in HBeAg-positive subjects are needed.展开更多
In cancer biology,mesenchymal stem cells(MSCs)display aspects that can appear contradictory.On one hand,these cells possess several features which give them the ability to specifically target and then sustain cancer c...In cancer biology,mesenchymal stem cells(MSCs)display aspects that can appear contradictory.On one hand,these cells possess several features which give them the ability to specifically target and then sustain cancer cells in their ability to survive the multifaceted host response against cancer.On the other hand,due to this excellent aptitude to home-in on tumor tissues,regardless their location in the host’s body,MSCs are considered to be extremely selective vehicles to reach cancer cells specifically.Recently,MSC sustainment of cancer cell growth is a hot research topic.Indeed,these cells are known to sustain tumor angiogenesis and metastasis formation,to create a microenvironment favorable for cancer cell growth and to down-modulate the immune system capabilities in the host organism.On the other hand,since scientists became able to take advantage of their extremely selective capability to target cancer cells,MSCs are now also thought of in a different light.Indeed,MSCs are now considered a promising vehicle for local expression or delivery of even particularly toxic anticancer agents,ranging from Herpes Simplex Virus to locally-acting antineoplastic drugs.On this basis,investigation is now focused on how to impair the pro-neoplastic features of MSCs on one hand whilst taking advantage of their specific tropism toward cancer cells,on the other.As with the two faces of Janus,this review will concisely explore the research activity in these two apparently conflicting fields.展开更多
Clear-cutting, a management practice applied to many beech forests in the North of Spain, modifies microclimate and, consequently, the composition of the understory plant community in the disturbed areas. The objectiv...Clear-cutting, a management practice applied to many beech forests in the North of Spain, modifies microclimate and, consequently, the composition of the understory plant community in the disturbed areas. The objectives of this study were to assess if changes in the understory vegetation caused by altered light microclimate after clear-cutting affect the infectivity of arbuscular mycorrhizal fungi （AMF） on herbaceous plant species in beech （Fagus sylvatica L.） forests naturally regenerating from clear-cutting and to test if the use of bioassays for studying the infectivity of native AMF could provide useful information to improve the management of clear-cut areas. Three nearby beech forests in northwest Navarra, Spain, a region in the northwest part of the Pyrenees, were selected： an unmanaged forest, a forest clear-cut in 1996, and another forest clear-cut in 2001. High stem density in the forest clear-cut in 1996 （44 000 trees ha-1） attenuated photosynthetic active radiation （PAR） and impaired the growth of herbaceous species within the ecosystem. The percentage of AMF colonization of plants in bioassays performed on soil samples collected from the forest clear-cut in 1996 was always lower than 10S. In the forest clear-cut in 2001, where soil was covered by perennial grasses, PAR was high and the infectivity of native AMF achieved minimum values in spring and autumn and a maximum value in summer. In contrast, the infectivity of native AMF in the unmanaged forest remained similar across the seasons. Our results demonstrated that changes in the composition of understory vegetation within beech forests strongly affected the infectivity of native AMF in clear-cut areas and suggested that the assessment of the infectivity of native AMF through bioassays could provide helpful information for planning either the removal of overstory when the tree density is so high that it impairs the correct development of herbaceous species or the plantation of new seedlings when high light intensity negatively affects the establishment of shade species.展开更多
Human papillomavirus 18(HPV18) E6 and E7 oncogenes are transcribed as a single bicistronic E6 E7 pre-mRNA. The E6 ORF region in the bicistronic E6 E7 pre-mRNA contains an intron. Splicing of this intron disrupts the E...Human papillomavirus 18(HPV18) E6 and E7 oncogenes are transcribed as a single bicistronic E6 E7 pre-mRNA. The E6 ORF region in the bicistronic E6 E7 pre-mRNA contains an intron. Splicing of this intron disrupts the E6 ORF integrity and produces a spliced E6*I RNA for efficient E7 translation. Here we report that the E6 intron has two overlapped branch point sequences(BPS) upstream of its 30 splice site, with an identical heptamer AACUAAC, for E6*I splicing. One heptamer has a branch site adenosine(underlined) at nt 384 and the other at nt 388. E6*I splicing efficiency correlates to the expression level of E6 and E7 proteins and depends on the selection of which branch site. In general, E6*I splicing prefers the 30 ss-proximal branch site at nt 388 over the distal branch site at nt 384. Inactivation of the nt 388 branch site was found to activate a cryptic acceptor site at nt 636 for aberrant RNA splicing. Together, these data suggest that HPV18 modulates its production ratio of E6 and E7 proteins by alternative selection of the two mapped branch sites for the E6*I splicing, which could be beneficial in its productive or oncogenic infection according to the host cell environment.展开更多
Vasomotion is a rhythmical variation in arterial blood flow present in many different organs among them the mttestis. Vasomofion is suggested to play an important role for the transvascular fluid exchange and the exch...Vasomotion is a rhythmical variation in arterial blood flow present in many different organs among them the mttestis. Vasomofion is suggested to play an important role for the transvascular fluid exchange and the exchange of nutri-ents over the capillary wall as well as the formation of interstitial fluid. The present study was undertaken to elucidatewhether vasomotion is present in the testes of different species independent of their anatomical vascular topography.Blood flow in the testes of mouse, brush-tailed possum, tammar wallaby, ram and human was investigated by using alaser Doppler fiowmeter. Vasomotion was found in all the species investigated. (Asian J Androl 2000 Dec; 2: 297-30O)展开更多
Selectins are carbohydrate-binding cell adhesion molecules that play a major role in the initiation of inflammatory responses. Accumulaed evidence has suggested that heparin＇s anti-inflammatory effects are mainly med...Selectins are carbohydrate-binding cell adhesion molecules that play a major role in the initiation of inflammatory responses. Accumulaed evidence has suggested that heparin＇s anti-inflammatory effects are mainly mediated by blocking L-or P-selectin-initiated cell adhesion. Recently, we have reported that periodate-oxidized, borohydridereduced heparin （RO-heparln） can inhibit P-selectin-mediated acute inflammation. Here we further examined the effect of RO-heparin on the adhesion of L-selectin-mediated leukocytes to vascular endothelium under flow conditions in vivo and in vitro. The results show that RO-heparin with a low anticoagulant activity can effectively reduce leucocyte roiling on thioglycoUate-induced rat mesenterlc venules and L-selectin-metadiated neutrophil roiling on TNF-α-induced human umbilical vein endothelial cells（HUVECs） under flow conditions. Our findings suggest that the effect of RO-heparin on inflammatory responses is mainly a result of its inhibiting the interaction between P- or L-selectin and its ligands. The findings also suggest that RO-heparin may be useful in preventing inflammation diseases.展开更多
Fleshy fruit ripening is governed by multiple external and internal cues and accompanied by changes in color,texture,volatiles,and nutritional quality traits.While extended shelf-life and increased phytonutrients are ...Fleshy fruit ripening is governed by multiple external and internal cues and accompanied by changes in color,texture,volatiles,and nutritional quality traits.While extended shelf-life and increased phytonutrients are desired,delaying ripening via genetic or postharvest means can be accompanied by reduced nutritional value.Here we report that the high pigment 1(hp1)mutation at the UV-DAMAGED DNA BINDING PROTEIN 1(DDB1)locus,previously shown to influence carotenoid and additional phytonutrient accumulation via altered light signal transduction,also results in delayed ripening and firmer texture,resulting at least in part from decreased ethylene evolution.Transcriptome analysis revealed multiple ethylene biosynthesis and signaling-associated genes downregulated in hp1.Furthermore,the hp1 mutation impedes softening of the pericarp,placenta,columella as well as the whole fruit,in addition to reduced expression of the FRUITFUL2(FUL2)MADS-box transcription factor and xyloglucan endotransglucosylase/hydrolase 5(XTH5).These results indicate that DDB1 influences a broader range of fruit development and ripening processes than previously thought and present an additional genetic target for increasing fruit quality and shelf-life.展开更多
基金supported by the National Key Research and Development Program of China(2023YFF0805602)National Natural Science Foundation of China(32225032,32001192,32271597)+1 种基金the Innovation Base Project of Gansu Province(2021YFF0703904)the Science and Technology Program of Gansu Province(24JRRA515,22JR5RA525,23JRRA1157).
文摘Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmental gradients.Particularly,the relative importance(RIV)of different plant life forms in a community and how they vary with environmental variables are still unclear.To fill these gaps,we determined plant diversity of ephemeral plants,annual herbs,perennial herbs,and woody plants from 187 sites across drylands in China.The SR patterns of herbaceous plants,especially perennial herbs,and their RIV in plant communities increased with increasing precipitation and soil nutrient content;however,the RIV of annual herbs was not altered along these gradients.The SR and RIV of ephemeral plants were affected mainly by precipitation seasonality.The SR of woody plants had a unimodal relationship with air temperature and exhibited the highest RIV and SR percentage in plant communities under the harshest environments.An obvious shift emerged in plant community composition,SR and their critical impact factors at 238.5 mm of mean annual precipitation(MAP).In mesic regions(>238.5 mm),herbs were the dominant species,and the SR displayed a relatively slow decreasing rate with increasing aridity,which was mediated mainly by MAP and soil nutrients.In arid regions(<238.5 mm),woody plants were the dominant species,and the SR displayed a relatively fast decreasing rate with increasing aridity,which was mediated mainly by climate variables,especially precipitation.Our findings highlight the importance of comparative life form studies in community structure and biodiversity,as their responses to gradients differed substantially on a large scale.
基金supported by the by the Fundamental Research Grant Scheme(Grant No.FRGS/1/2023/STG03/UM/02/2)Universiti Malaya RU Fund(Grant No.ST087-2022).
文摘Biotechnology has revolutionized agriculture through innovations such as genetically modified(GM)technology and CRISPR/Cas9 genome editing.In this review,a comparative analysis of these methods that addresses the concerns regarding the oversimplification of the notion that the CRISPR-based editing approach is equivalent to traditional GM approaches is offered.Since the 1990s,despite the potential benefits for crop improvement and food security,controversies have arisen around recombinant technology and the introduction of GM products due to perceived environmental and health concerns.In contrast,the recent emergence of the CRISPR/Cas systemas a precise genome editing tool has garnered relatively less public resistance.In this review,the reasons for these contrasting findings are explored to shed light on the distinct characteristics inherent to each approach.Additionally,we conduct a bibliographic analysis to examine the shift in research priorities between the two technological eras,followed by a comprehensive comparison of the two approaches,to enable a better understanding of the potential synergies that can be achieved between agricultural biotechnology and conventional techniques for enhancing modern agriculture.A nuanced understanding of these technologies is crucial for informed decision-making,responsible implementation,and addressing the concerns surrounding agricultural biotechnology.
基金supported by The Shenzhen Educational Research Funding(zdzb2014)The Shenzhen Science and Technology Innovation Commission(202307313000096)+4 种基金The Social Science Foundation from the China's Ministry of Education(23YJA880093)The Post-Doctoral Fellowship(2022M711174)The National Center for Mental Health(Z014)BC is supported by the Chaires de recherche Rennes Métropole(23C 0909)SM is supported by the National Insti-tutes of Health(R01AG72445).
文摘Today, most people know that physical activity(PA) is beneficial for their health ^(1,2)and aspire to engage in regular PA.^(3,4)However, despite their awareness of the importance of PA, it is evident that the transition from intention to action is challenging-a situation that has important public health implications. According to the World Health Organization,^(5)1 person dies every 6 s worldwide from causes related to physical inactivity, which underscores the urgency of addressing this situation.
文摘In this study,we investigated how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest communities.In the oldest pure communi-ties of Pinus nigra(PN),Fagus orientalis(FO),and Abies bornmuelleriana(AB)in the mountain range of Mount Uludağ,Bursa,Turkey,annual net yield and N mineraliza-tion in the 0-5-and 5-20-cm soil layers were determined in a field incubation study over 1 year.Sampling locations were chosen from 1300 to 1600 m a.s.l.,and moisture content(%),pH,water-holding capacity(%),organic C,total N,and C/N ratio,and annual net mineral N yield of the soil and hydro-lyzed tannic acid and total phenolic compounds in litter were compared for these forest communities.F.orientalis had the highest annual net Nmin yield(43.9±4.8 kg ha^(-1) a^(-1)),P.nigra the lowest(30.5±4.2 kg ha^(-1) a^(-1)).Our findings show that in the oldest forest ecosystems,the seasonal soil moisture content and tree species play an essential role in N cycling and that hydrolyzed tannic acids and total phenolic compounds effectively control N turnover.Tannic acid and total phenolics in the litter were found to inhibit nitrification,but total phenolics were found to stimulate ammonification.
基金the Bundesministerium für Bildung und Forschung(BMBF)-funded deNBI cloud within German Network for Bioinformatics Infrastructure(de.NBI)(Nos.031A532B,031A533A,031A533B,031A534A,031A535A,031A537A,031A537B,031A537C,031A537D,031A538A)for providing computational resources.Florin Musat was funded by the Helmholtz Association of German Research Centres Grant ERC-RA-0020+2 种基金the Novo Nordisk Foundation through an NNF Young Investigator Award,Grant NNF22OC0071609 ReFuel(grants to F.M.).Song-Can Chen is supported by Marie Skłodowska-Curie Actions 2021(postdoctoral fellowship 101059607 to S.C.C.).All sequencing data generated in this study have been deposited in the Sequence Read Archive under BioProject PRJNA1017987(SAMN37419328-SAMN374193).
文摘The Arctic,an essential ecosystem on Earth,is subject to pronounced anthropogenic pressures,most notable being the climate change and risks of crude oil pollution.As crucial elements of Arctic environments,benthic microbiomes are involved in climate-relevant biogeochemical cycles and hold the potential to remediate upcoming contamination.Yet,the Arctic benthic microbiomes are among the least explored biomes on the planet.Here we combined geochemical analyses,incubation experiments,and microbial community profiling to detail the biogeography and biodegradation potential of Arctic sedimentary microbiomes in the northern Barents Sea.The results revealed a predominance of bacterial and archaea phyla typically found in the deep marine biosphere,such as Chloroflexi,Atribacteria,and Bathyarcheaota.The topmost benthic communities were spatially structured by sedimentary organic carbon,lacking a clear distinction among geographic regions.With increasing sediment depth,the community structure exhibited stratigraphic variability that could be correlated to redox geochemistry of sediments.The benthic microbiomes harbored multiple taxa capable of oxidizing hydrocarbons using aerobic and anaerobic pathways.Incubation of surface sediments with crude oil led to proliferation of several genera from the so-called rare biosphere.These include Alkalimarinus and Halioglobus,previously unrecognized as hydrocarbon-degrading genera,both harboring the full genetic potential for aerobic alkane oxidation.These findings increase our understanding of the taxonomic inventory and functional potential of unstudied benthic microbiomes in the Arctic.
基金supported by grants from the NIH(P01DK113954,R01DK115761,R01DK117281,R01DK125480 and R01DK120858 to YXR01DK129548 to YH)+1 种基金USDA/CRIS(51000-064-01S to YX)Postdoctoral Fellowship(2020AHA000POST000204188)to LT。
文摘Glucose is the primary fuel source of the brain,and therefore glucose levels need to be tightly regulated and maintained within a small physiological range.Certainly,the body necessitates a stable supply of energy mainly provided by glucose for various bodily functions.High or low blood glucose levels would impair the physiological functions of various organs of the body.
文摘Aim： To perform screening, related to A-kinase anchoring proteins 4 （AKAP4） and tubulin proteins, in spermatozoa with absent or severely reduced motility in order to detect the status of the fibrous sheath and the axonemal structure. Methods： An immunocytochemical study of tubulin, used as a positive control, and AKAP4 was carded out to detect the presence and the distribution of these proteins in different sperm samples. The morphological characteristics of sperm were studied by transmission electron microscope （TEM） and the results were elaborated using a formula reported in previous studies. PCR was carried out on DNA extracted from peripheral blood lymphocytes to analyse partial sequences of the Akap4 and Akap3 genes. Results： Immunolabelling of tubulin and AKAP4 showed different patterns, which led us to divide the patients into groups. In group I, the absence of AKAP4 and tubulin was revealed, although these patients did not show alterations in the Akap4/Akap3 binding site. TEM evaluation highlighted that a high presence of necrosis was associated with total sperm immotility. In group Ⅱ, a regular AKAP4 and tubulin signal was present, although motility was reduced and TEM analysis revealed the presence of immaturity. In group Ⅲ, in which a weak AKAP4 label associated with normal tubulin staining and reduced motility was observed, a severe disorganization of the fibrous sheath was highlighted by TEM. Conclusion： While the role of AKAP4 in sperm motility is unclear, absent or weak AKAP4-1abelling seems to be associated with absent or weak sperm motility.
文摘Low availability of phosphorus(P) is a major constraint for optimal crop production, as P is mostly present in its insoluble form in soil. Therefore,phosphate-solubilizing bacteria(PSB) from paddy field soils of the Indo-Gangetic Plain, India were isolated, and their abundance was attempted to be correlated with the physicochemical characteristics of the soils. Ninety-four PSB were isolated on Pikovskaya’s agar medium, and quantitative phosphate solubilization was evaluated using NBRIP medium. The isolates solubilized P up to a concentration of 1 006 μg mL-1 from tricalcium phosphate with the secretion of organic acids. These isolates were identified by 16 S rRNA gene sequence comparison, and they belonged to Gammaproteobacteria(56 isolates),Firmicutes(28 isolates), Actinobacteria(8 isolates), and Alphaproteobacteria(2 isolates). Phylogenetic analysis confirmed the identification by clustering the isolates in the clade of the respective reference organisms. The correlation analysis between PSB abundance and physicochemical characteristics revealed that the PSB population increased with increasing levels of soil organic carbon, insoluble P, K+, and Mg2+. The promising PSB explored in this study can be further evaluated for their biofertilizer potential in the field and for their use as potent bio-inoculants.
文摘Aim： To study the immune-modulating and anti-oxidant effects of beta-glucan, papaya, lactoferrin, and vitamins C and E on sperm characteristics of patients with asthenoteratozoospermia associated with leucocytosis. Methods： Fifty-one patients referred to our Sterility Center for semen analysis were selected. Sperm parameters were assessed before and after patient＇s treatment with beta-glucan, lactoferrin, papaya, and vitamins C and E. DNA damage was assessed by the acridine orange test and sperm structural characteristics were evaluated by transmission electron microscopy. Results： After 90 days of treatment, an increase in the percentage of morphologically normal sperm （17.0 ± 5.2 vs. 29.8 ± 6.5） and total progressive motility （19.0± 7.8 vs. 34.8 ± 6.8） were detected. Structural sperm characteristics as well as chromatin integrity were also improved after treatment. In terms of leukocyte concentration in seminal fluid, a significant reduction was recorded （2.2 ± 0.9 vs. 0.9± 0.2）. Conclusion： The treatment of an inflammatory process by the synergic action of immune modulators and anti-oxidants could protect sperm during maturation and migration, leading to improved sperm function. （Asian JAndrol 2008 Mar;. 10： 201-206）
基金supported by the Intramural Research Programs of the National Institute of Diabetes and Digestive and Kidney Diseases and of the National Institute of Dental and Craniofacial Research at the National Institutes of Health
文摘Erythropoietin is essential for bone marrow erythropoiesis and erythropoietin receptor on non-erythroid cells including bone marrow stromal cells suggests systemic effects of erythropoietin. Tg6 mice with chronic erythropoietin overexpression have a high hematocrit, reduced trabecular and cortical bone and bone marrow adipocytes, and decreased bone morphogenic protein 2 driven ectopic bone and adipocyte formation. Erythropoietin treatment(1 200 IU·kg–1) for 10 days similarly exhibit increased hematocrit,reduced bone and bone marrow adipocytes without increased osteoclasts, and reduced bone morphogenic protein signaling in the bone marrow. Interestingly, endogenous erythropoietin is required for normal differentiation of bone marrow stromal cells to osteoblasts and bone marrow adipocytes.ΔEpoR_E mice with erythroid restricted erythropoietin receptor exhibit reduced trabecular bone, increased bone marrow adipocytes, and decreased bone morphogenic protein 2 ectopic bone formation. Erythropoietin treated ΔEpoR_E mice achieved hematocrit similar to wild-type mice without reduced bone, suggesting that bone reduction with erythropoietin treatment is associated with non-erythropoietic erythropoietin response. Bone marrow stromal cells from wild-type,Tg6, and ΔEpoR_E-mice were transplanted into immunodeficient mice to assess development into a bone/marrow organ. Like endogenous bone formation, Tg6 bone marrow cells exhibited reduced differentiation to bone and adipocytes indicating that high erythropoietin inhibits osteogenesis and adipogenesis, while ΔEpoR_E bone marrow cells formed ectopic bones with reduced trabecular regions and increased adipocytes, indicating that loss of erythropoietin signaling favors adipogenesis at the expense of osteogenesis. In summary, endogenous erythropoietin signaling regulates bone marrow stromal cell fate and aberrant erythropoietin levels result in their impaired differentiation.
文摘We analysed ejaculated spermatozoa from five infertile men with different balanced reciprocal translocations to contribute to the study of meiotic segregation of chromosomes 18, X and Y and also to evaluate sperm morphology by transmission electron microscopy （TEM） analysis. Conventional lymphocyte karyotype analyses highlighted dif- ferent reciprocal balanced translocations： t（12; 13）, t（4;9）, t（X;8）, t（8; 10） and t（3; 16）. Semen analysis was performed by light and TEM. Fluorescence in situ hybridization was performed directly on sperm nuclei using centromeric probes for chromosomes 18, X and Y. The carriers of the balanced reciprocal translocations considered in the present study showed a very similar pattern of sperm pathologies： diffused presence of apoptosis and immaturity. All patients showed meiotic segregation derangements, highlighted by the presence of sperm diploidies and sex chromosome disomies particularly related to the failure of the first meiotic division. However, an increased incidence of chromosome 18 aneuploidy was detected in spermatozoa from t（X;8） and t（8;10） carriers. We have also reported values from sex chromosomes such as t（X;8）, although the X chromosome was involved in translocation. Since patients with reciprocal translocations and spermatogenetic impairment are candidates for intracytoplasmic sperm injection cycles, the study of sperm parameters, and particularly of the level of aneuploidy rates, would provide better information for couples at risk and would contribute to the data in the literature for a better understanding of the effects of chromosomal rearrangement on the whole meiotic process and, in particular, on chromosomes not involved in translocation.
基金supported by grants from the China Natural Science Foundation (81825015 and 31630086)the Natural Science Foundation of Hubei Province Innovation Group (2017CFA022)Intramural Research Program of NCI/NIH (1ZIASC010357 to ZMZ)
文摘RNA granules are cytoplasmic, microscopically visible, non-membrane ribo-nucleoprotein structures and are important posttranscriptional regulators in gene expression by controlling RNA translation and stability. TIA/G3BP/PABP-specific stress granules(SG) and GW182/DCP-specific RNA processing bodies(PB) are two major distinguishable RNA granules in somatic cells and contain various ribosomal subunits, translation factors, scaffold proteins, RNA-binding proteins, RNA decay enzymes and helicases to exclude m RNAs from the cellular active translational pool. Although SG formation is inducible due to cellular stress, PB exist physiologically in every cell. Both RNA granules are important components of the host antiviral defense. Virus infection imposes stress on host cells and thus induces SG formation. However, both RNA and DNA viruses must confront the hostile environment of host innate immunity and apply various strategies to block the formation of SG and PB for their effective infection and multiplication. This review summarizes the current research development in the field and the mechanisms of how individual viruses suppress the formation of host SG and PB for virus production.
文摘AIM: To study the efficacy of tenofovir disoproxil fumarate (TDF) at low dose in a small open trial of chronic hepatitis B patients with advanced stage disease. METHODS: Eleven patients were treated with TDF 75 mg for a median period of 80 (range, 24-576) wk and then 7 cases were shifted to an adefovir 10 mg treatment group. All patients had been pre-treated with lamivudine: 5 had YMDD resistant mutants and 6 wild- type virus. When TDF was started, 4 patients had low- level viremia and 6 were PCR-negative. RESULTS: During TDF treatment, PCR remained negative in 10 patients, transaminase levels were normal and no significant viral breakthrough was observed. The drug was well tolerated in all cases. When TDF 75 mg was substituted with adefovir 10 mg, 3 out of 7 patients had a persistent viral rebound (2700-130 000 copies/mL), in whom lamivudine had to be reintroduced. CONCLUSION: Low-dose TDF monotherapy can control HBV viremia for an extended period of time without the emergence of resistance and is more potent than adefovir at the standard dosage. The use of a reduced dose of TDF could diminish the cost of therapy in low-income countries, but further studies in a larger population and in HBeAg-positive subjects are needed.
基金Supported by Grants from Associazione Italiana Ricerca sul Cancro(AIRC) to Paggi MGMinistero della Salute grants to Paggi MGfrom Sbarro Health Research Organization funds to Galderisi U and Giordano A
文摘In cancer biology,mesenchymal stem cells(MSCs)display aspects that can appear contradictory.On one hand,these cells possess several features which give them the ability to specifically target and then sustain cancer cells in their ability to survive the multifaceted host response against cancer.On the other hand,due to this excellent aptitude to home-in on tumor tissues,regardless their location in the host’s body,MSCs are considered to be extremely selective vehicles to reach cancer cells specifically.Recently,MSC sustainment of cancer cell growth is a hot research topic.Indeed,these cells are known to sustain tumor angiogenesis and metastasis formation,to create a microenvironment favorable for cancer cell growth and to down-modulate the immune system capabilities in the host organism.On the other hand,since scientists became able to take advantage of their extremely selective capability to target cancer cells,MSCs are now also thought of in a different light.Indeed,MSCs are now considered a promising vehicle for local expression or delivery of even particularly toxic anticancer agents,ranging from Herpes Simplex Virus to locally-acting antineoplastic drugs.On this basis,investigation is now focused on how to impair the pro-neoplastic features of MSCs on one hand whilst taking advantage of their specific tropism toward cancer cells,on the other.As with the two faces of Janus,this review will concisely explore the research activity in these two apparently conflicting fields.
基金Supported by the University Foundation of Navarra,Spainthe Caja Navarra,Spainand the University of Navarra,Inc.,Spain.
文摘Clear-cutting, a management practice applied to many beech forests in the North of Spain, modifies microclimate and, consequently, the composition of the understory plant community in the disturbed areas. The objectives of this study were to assess if changes in the understory vegetation caused by altered light microclimate after clear-cutting affect the infectivity of arbuscular mycorrhizal fungi （AMF） on herbaceous plant species in beech （Fagus sylvatica L.） forests naturally regenerating from clear-cutting and to test if the use of bioassays for studying the infectivity of native AMF could provide useful information to improve the management of clear-cut areas. Three nearby beech forests in northwest Navarra, Spain, a region in the northwest part of the Pyrenees, were selected： an unmanaged forest, a forest clear-cut in 1996, and another forest clear-cut in 2001. High stem density in the forest clear-cut in 1996 （44 000 trees ha-1） attenuated photosynthetic active radiation （PAR） and impaired the growth of herbaceous species within the ecosystem. The percentage of AMF colonization of plants in bioassays performed on soil samples collected from the forest clear-cut in 1996 was always lower than 10S. In the forest clear-cut in 2001, where soil was covered by perennial grasses, PAR was high and the infectivity of native AMF achieved minimum values in spring and autumn and a maximum value in summer. In contrast, the infectivity of native AMF in the unmanaged forest remained similar across the seasons. Our results demonstrated that changes in the composition of understory vegetation within beech forests strongly affected the infectivity of native AMF in clear-cut areas and suggested that the assessment of the infectivity of native AMF through bioassays could provide helpful information for planning either the removal of overstory when the tree density is so high that it impairs the correct development of herbaceous species or the plantation of new seedlings when high light intensity negatively affects the establishment of shade species.
基金fully supported by Intramural Research Program of the National Institutes of Health, National Cancer Institute, Center for Cancer Research (1ZIASC010357 to ZMZ)a part of Brant AC Ph.D thesis being developed at the Post-graduate program in Genetics (PGGEN) of Rio de Janeiro Federal University (UFRJ), Rio de Janeiro, Brazil+2 种基金the National Cancer Institute of USAsupported by the PDSE program of Coordenacao de Aperfeicoamento de Pessoal de Nível Superior (Capes, Brazil)the National Cancer Institute of USA
文摘Human papillomavirus 18(HPV18) E6 and E7 oncogenes are transcribed as a single bicistronic E6 E7 pre-mRNA. The E6 ORF region in the bicistronic E6 E7 pre-mRNA contains an intron. Splicing of this intron disrupts the E6 ORF integrity and produces a spliced E6*I RNA for efficient E7 translation. Here we report that the E6 intron has two overlapped branch point sequences(BPS) upstream of its 30 splice site, with an identical heptamer AACUAAC, for E6*I splicing. One heptamer has a branch site adenosine(underlined) at nt 384 and the other at nt 388. E6*I splicing efficiency correlates to the expression level of E6 and E7 proteins and depends on the selection of which branch site. In general, E6*I splicing prefers the 30 ss-proximal branch site at nt 388 over the distal branch site at nt 384. Inactivation of the nt 388 branch site was found to activate a cryptic acceptor site at nt 636 for aberrant RNA splicing. Together, these data suggest that HPV18 modulates its production ratio of E6 and E7 proteins by alternative selection of the two mapped branch sites for the E6*I splicing, which could be beneficial in its productive or oncogenic infection according to the host cell environment.
文摘Vasomotion is a rhythmical variation in arterial blood flow present in many different organs among them the mttestis. Vasomofion is suggested to play an important role for the transvascular fluid exchange and the exchange of nutri-ents over the capillary wall as well as the formation of interstitial fluid. The present study was undertaken to elucidatewhether vasomotion is present in the testes of different species independent of their anatomical vascular topography.Blood flow in the testes of mouse, brush-tailed possum, tammar wallaby, ram and human was investigated by using alaser Doppler fiowmeter. Vasomotion was found in all the species investigated. (Asian J Androl 2000 Dec; 2: 297-30O)
文摘Selectins are carbohydrate-binding cell adhesion molecules that play a major role in the initiation of inflammatory responses. Accumulaed evidence has suggested that heparin＇s anti-inflammatory effects are mainly mediated by blocking L-or P-selectin-initiated cell adhesion. Recently, we have reported that periodate-oxidized, borohydridereduced heparin （RO-heparln） can inhibit P-selectin-mediated acute inflammation. Here we further examined the effect of RO-heparin on the adhesion of L-selectin-mediated leukocytes to vascular endothelium under flow conditions in vivo and in vitro. The results show that RO-heparin with a low anticoagulant activity can effectively reduce leucocyte roiling on thioglycoUate-induced rat mesenterlc venules and L-selectin-metadiated neutrophil roiling on TNF-α-induced human umbilical vein endothelial cells（HUVECs） under flow conditions. Our findings suggest that the effect of RO-heparin on inflammatory responses is mainly a result of its inhibiting the interaction between P- or L-selectin and its ligands. The findings also suggest that RO-heparin may be useful in preventing inflammation diseases.
基金supported by the National Science Fund of China for Distinguished Young Scholars(30825030)the National Natural Science Foundation of China(31671259).
文摘Fleshy fruit ripening is governed by multiple external and internal cues and accompanied by changes in color,texture,volatiles,and nutritional quality traits.While extended shelf-life and increased phytonutrients are desired,delaying ripening via genetic or postharvest means can be accompanied by reduced nutritional value.Here we report that the high pigment 1(hp1)mutation at the UV-DAMAGED DNA BINDING PROTEIN 1(DDB1)locus,previously shown to influence carotenoid and additional phytonutrient accumulation via altered light signal transduction,also results in delayed ripening and firmer texture,resulting at least in part from decreased ethylene evolution.Transcriptome analysis revealed multiple ethylene biosynthesis and signaling-associated genes downregulated in hp1.Furthermore,the hp1 mutation impedes softening of the pericarp,placenta,columella as well as the whole fruit,in addition to reduced expression of the FRUITFUL2(FUL2)MADS-box transcription factor and xyloglucan endotransglucosylase/hydrolase 5(XTH5).These results indicate that DDB1 influences a broader range of fruit development and ripening processes than previously thought and present an additional genetic target for increasing fruit quality and shelf-life.
