Sequencing of environmental samples has great potential for biodiversity research,but its application is limited by the lack of reliable DNA barcode databases for species identifications.Such a database has been creat...Sequencing of environmental samples has great potential for biodiversity research,but its application is limited by the lack of reliable DNA barcode databases for species identifications.Such a database has been created for epiphytic lichens of Europe,allowing us to compare the results of environmental sequencing with standard taxonomic surveys.The species undetected by taxonomic surveys(what we term the ghost component)amount to about half of the species actually present in hectare plots of Central European forests.Some of these,which currently occur only as diaspores or weakly developed thalli,are likely to be favoured in the course of global change.The ghost component usually represents a larger fraction in managed forests than in old-growth unmanaged forests.The total species composition of different plots is much more similar than suggested by taxonomic surveys alone.On a regional scale,this supports the well-known statement that“everything is everywhere,but,the environment selects”.展开更多
Fire disturbances are increasing under global climate change and ecological transformations of forests are occurring.Specifically,shifts from productive closed-canopy feather moss forests to low-productivity open-cano...Fire disturbances are increasing under global climate change and ecological transformations of forests are occurring.Specifically,shifts from productive closed-canopy feather moss forests to low-productivity open-canopy lichen(Cladonia spp.)woodlands have been observed in boreal forests of eastern Canada.It has been hypothesized that high severity of fires would be the cause of this change,but this is difficult to validate a posteriori on mature forest stands.Because charcoal properties are affected by fire severity,we have put forward the hypothesis that the amount and physicochemical properties of charcoal(C,N,H,O,ash,surface area)would be different and indicative of a greater fire severity for open-canopy forests compared to closed canopy ones.Our hypothesis was partly validated in that the amount of charcoal found on the ground of closed-canopy forests was greater than that of open-canopy forests.However,the physicochemical properties were not different,albeit a greater variability of charcoal properties for open canopy stands.These results do not allow us to fully validate or reject our hypothesis on the role of fire severity in the shift between open and closed canopy stands.However,they suggest that the variability in fire conditions as well as the amounts of charcoal produced are different between the two ecosystem types.Furthermore,considering the role that biochar may play in improving soil conditions and promoting vegetation restoration,our results suggest that charcoal may play a role in maintaining these two stable alternative ecosystem states.展开更多
Background:The heartwood(HW)proportion in the trunk of mature trees is an important characteristic not only for wood quality but also for assessing the role of forests in carbon sequestration.We have for the first tim...Background:The heartwood(HW)proportion in the trunk of mature trees is an important characteristic not only for wood quality but also for assessing the role of forests in carbon sequestration.We have for the first time studied the proportion of HW in the trunk and the distribution of carbon and extractives in sapwood(SW)and HW of 70–80 year old Pinus sylvestris L.trees under different growing conditions in the pine forests of North-West Russia.Method:We have examined the influence of conditions and tree position in stand(dominant,intermediate and suppressed trees)in the ecological series:blueberry pine forest(Blu)–lingonberry pine forest(Lin)–lichen pine forest(Lic).We have analyzed the influence of climate conditions in the biogeographical series of Lin:the middle taiga subzone–the northern taiga subzone–the transition area of the northern taiga subzone and tundra.Results:We found that the carbon concentration in HW was 1.6%–3.4%higher than in SW,and the difference depended on growing conditions.Carbon concentration in HW increased with a decrease in stand productivity(Blu-Lin-Lic).In medium-productive stands,the carbon concentration in SW was higher in intermediate and supressed trees compared to dominant trees.In the series from south to north,carbon concentration in HW increased by up to 2%,while in SW,it rose by 2.7%–3.8%.Conclusions:Our results once again emphasized the need for an empirical assessment of the accurate carbon content in aboveground wood biomass,including various forest growing conditions,to better understand the role of boreal forests in carbon storage.展开更多
Decorin(DCN)is primarily found in the connective tissues of various parts of the body,including the lungs,kidneys,bone tissue,aorta,and tendons.It is an important component of the extracellular matrix(ECM)and belongs ...Decorin(DCN)is primarily found in the connective tissues of various parts of the body,including the lungs,kidneys,bone tissue,aorta,and tendons.It is an important component of the extracellular matrix(ECM)and belongs to the class I small leucine-rich proteoglycans family.DCN is increasingly attracting attention due to its significant role in tumors,fibrotic diseases,and the regulation of vascular formation.Moreover,its anti-tumor properties have positioned it as a promising biomarker in the fight against cancer.Numerous studies have confirmed that DCN can exert inhibitory effects in various solid tumors,particularly in oral squamous cell carcinoma(OSCC),by activating its downstream pathways through binding with the epidermal growth factor receptor(EGFR)and mesenchymal-epithelial transition(MET)receptor,or by stabilizing and enhancing the expression of the tumor suppressor gene p53 to mediate apoptosis in cancer cells that have undergone mutation.The occurrence of OSCC is a continuous and dynamic process,encompassing the transition from normal mucosa to oral potentially malignant disorders(OPMDs),and further progressing from OPMDs to the malignant transformation into OSCC.We have found that DCN may exhibit a bidirectional effect in the progression of oral mucosal carcinogenesis,showing a trend of initial elevation followed by a decline,which decreases with the differentiation of OSCC.In OPMDs,DCN exhibits high expression and may be associated with malignant transformation,possibly linked to the increased expression of P53 in OPMDs.In OSCC,the expression of DCN is reduced,which can impact OSCC angiogenesis,and inhibit tumor cell proliferation,migration,and invasion capabilities,serving as a potential marker for predicting adverse prognosis in OSCC patients.This article reviews the current research status of DCN,covering its molecular structure,properties,and involvement in the onset and progression of oral mucosal carcinogenesis.It elucidates DCN’s role in this process and aims to offer insights for future investigations into its mechanism of action in oral mucosal carcinogenesis and its potential application in the early diagnosis and treatment of OSCC.展开更多
Lichens,as dual organisms comprising a major mycobiont and a major photobiont,exhibit remarkable survival capabilities in extreme conditions,such as those found in Antarctica.Despite their adaptability,the diversity a...Lichens,as dual organisms comprising a major mycobiont and a major photobiont,exhibit remarkable survival capabilities in extreme conditions,such as those found in Antarctica.Despite their adaptability,the diversity and distribution of lichen photobionts in the ice-free areas of maritime Antarctica remain less understood compared to their mycobiont counterparts.In our study,we investigated the diversity of both lichen mycobionts and photobionts in 56 samples collected from the Fildes Region on King George Island,maritime Antarctica.Through sequencing of the nuclear ribosomal internal transcribed spacer regions and subsequent phylogenetic analysis,we examined the relationships and association patterns between mycobionts and photobionts.Our findings revealed 19 taxa of lichen mycobionts across 13 families and seven orders,along with nine photobiont species within the class Trebouxiophyceae.These photobionts encompassed six Trebouxia species,one Asterochloris species,one Chloroidium species,and one Stichococcus species.In particular,a new Trebouxia lineage(Trebouxia sp.OTU D08)and a new Chloroidium lineage were found.The analysis indicated that many mycobionts could be associated with multiple photobiont species,a pattern also observed among the photobionts.These results contribute significantly to our understanding of the complex diversity of lichen mycobionts and photobionts in the ice-free areas of maritime Antarctica.展开更多
Faeces were counted along horizontal, 5.0m wide strips at altitude intervals of 100m to examine the altitudinal ranging pattern of a band of black-and-white snub-nosed monkeys （Rhinopithecus bieti） at Nanren （99...Faeces were counted along horizontal, 5.0m wide strips at altitude intervals of 100m to examine the altitudinal ranging pattern of a band of black-and-white snub-nosed monkeys （Rhinopithecus bieti） at Nanren （99°04′E, 28°34′N, Baima Snow Mountain Nature Reverse, Yunnan, China） at four areas in each season between 2000-2001. Faeces were also counted along vertical, 2.5 m wide strips in one subvalley and on one subridge in each area. Monkeys used an altitudinal range of 3500-4300m, but preferred occupying the upper forest belt between 3900 and 4200m asl year-round, being at the highest altitude in summer, the lowest altitude in spring, and middle altitudes between autumn and winter （lower in winter than autumn）. Moreover, there were secondary peaks of lower altitude use （3700m） in spring and winter. In addition, more faeces were distributed in subvalleys than on subridges in winter, this suggests that monkeys tend to spend more time in subvalleys where there is less wind and fluctuating temperatures. The significant correlation between faecal density and lichen load might indicate that altitudinal distribution of food resources may act as an important factor affecting the monkeys＇ range. The monkeys might migrate to lower altitudes to eat young sprouts and leaves in spring, and to shelter from snowstorms in winter, possibly resulting in the secondary peaks at lower altitudes.展开更多
Oral lichen planus （OLP） is a chronic inflammatory disorder and premalignantlesion, of which the mechanisms are still obscure. In the present study, the expression levels of miR-96/182/183 cluster, miR-203, miR-375,...Oral lichen planus （OLP） is a chronic inflammatory disorder and premalignantlesion, of which the mechanisms are still obscure. In the present study, the expression levels of miR-96/182/183 cluster, miR-203, miR-375, and miR-769-5p in both tissues and exfoliative cells of OLP patients as well as healthy volunteers were detected, differentially expressed miRNAs were identified and their correlation with OLP was evaluated by a biplot method. Experimental results show that miR-203 is significantly up-regulated in patient lesion tissues in comparison to volunteer mucosa tissues. Moreover, the contra- dictory insignificant expression changes of miR-203 as well as miR-96/182/183 cluster in comparisons of exfoliative cell samples suggest that different cell compositions in OLP lesion have distinct miRNA regulation, which accords with the histological heterogeneity of OLP. Finally, biplot analyses indicate the expression of miR-203 and miR-96/182/183 cluster are positively correlated in patient lesions. These results provide miR-203 as a molecular indicator of heterogeneity of OLP, and also a potential diagnostic biomarker or therapeutic target that deserves further studies.展开更多
Biological soil crusts(BSCs)have important ecological functions in arid and semiarid lands,but they remain poorly understood in terms of the changes in microbial communities during BSC succession under in situ field c...Biological soil crusts(BSCs)have important ecological functions in arid and semiarid lands,but they remain poorly understood in terms of the changes in microbial communities during BSC succession under in situ field conditions.Here,454 pyrosequencing was used to assess the microbial community composition of four BSC types in the Tengger Desert of China:alga,lichen(cyanolichen and green alga-lichen),and moss crusts,representing early,middle,and final successional stages of BSCs,respectively.The results showed the highest diversity of microbial communities inhabiting lichen crusts,whereas the lowest diversity was observed in moss crusts.Five phyla,Proteobacteria,Actinobacteria,Cyanobacteria,Bacteroidetes,and Acidobacteria,accounted for about 72% to 87%of total prokaryotic sequences in different BSCs.The most abundant eukaryotic microorganism was Ascomycota,accounting for 47%to 93%of the total eukaryotic sequences.Along the succession of BSCs,the abundance of photoautotrophic Cyanobacteria,Chlorophyta,and Bacillariophyta declined,and that of heterotrophic microorganisms such as bacteria and fungi increased.Statistical analysis showed clear divergency of microbial taxa at the class level among the different successional stages of BSCs.The clustering results at class level showed that the moss crusts were the farthest from the rest in prokaryotic composition;the alga crusts were the most different in terms of eukaryotic microorganisms and the two kinds of lichen crusts were relatively closer in both compositions.Ordination analysis showed that the main variations of community structure among BSCs could be explained best by the abundance of Cyanobacteria and Ascomycota and by physiochemical properties of BSCs,including mechanical composition,moisture,and electrical conductivity.In conclusion,our results indicate that Cyanobacteria and Ascomycota likely play an important role in the evolution of BSC structure and functions and highlight the importance of environmental factors in shaping microbial community structures of BSCs in the Tengger Desert of China.展开更多
Crustose lichens are distributed extensively in karst areas in Southern China. They can be found on the surface of carbonate rocks. Through biophysical and biochemical processes, crustose lichens reform the subsurface...Crustose lichens are distributed extensively in karst areas in Southern China. They can be found on the surface of carbonate rocks. Through biophysical and biochemical processes, crustose lichens reform the subsurface of carbonate rocks and in the meanwhile change their physical and chemical properties: (1) the mechanical strength decreases by 17.04° on average (up to 33.2°); (2) the chemical solution surface area increases from 28.26% to 75.36% (lichen microholes considered only); and (3) the water-holding capacity is greatly improved. Comparative field experiments between biokarst samples underneath crustose lichens and fresh rock samples with the same composition and texture show that the corrosional rate of carbonate rocks of the former is 1.264–1.643 times higher than that of the latter. Crustose lichens are considered as an activator of the surface corrosion of carbonate rocks.展开更多
Oral lichen planus （OLP） is a chronic inflammatory disease that is frequently detected in oral tissues. The aim of our study was to identify the prevalence of the detection of periodontopathogenic microorganisms （A...Oral lichen planus （OLP） is a chronic inflammatory disease that is frequently detected in oral tissues. The aim of our study was to identify the prevalence of the detection of periodontopathogenic microorganisms （Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia and Treponema denticola in OLP patients and to compare with this prevalence of periodontopathogenic microorganisms in healthy non-OLP patients. Our study included 27 （18 chronic periodontitis （OLPP） and 9 gingivitis （OLPG）） patients diagnosed with OLP along with 26 （13 chronic periodontitis （HP） and 13 gingivitis （HG）） healthy non-OLP patients. The multiplex polymerase chain reaction （PCR）with subsequent reverse hybridization method （micro-IDent） was used for identifying periodontopathogenic microorganisms present in subgingival plaque samples. The percentages of detection for A. actinomycetemcomitans, P. gingivalis, P. intermedia, T. forsythia and T. denticola in subgingival plaque samples taken from OLP patients （OLPG and OLPP） were 18.5%, 85.1%, 81.4%, 88.8% and 74%, respectively. Meanwhile, in the non-OLP patients （HG and HP）, these values were 7.6%, 50%, 46.1%, 73% and 57.7%, respectively. Thus, comparing the non-OLP groups with the OLP groups, the periodontopathogens＇ percentages of detection in the OLP groups were higher than those in the non-OLP groups. According to our study results, OLP patients have higher levels of infection with A. actinomycetemcomitans, P. gingivalis, P. intermedia, T. forsythia and T. denticola than non-OLP patients. We argue that the high percentages in patients with OLP may help identify the importance of periodontopathoRenic microorganisms in the progress of periodontal diseases of OLP.展开更多
Our previous salivary study had demonstrated an apparent T helper 2 （Th2）-predominance in saliva of oral lichen planus （OLP） patients and suggested a potential of salivary interleukin-4 （IL-4） as a biomarker for...Our previous salivary study had demonstrated an apparent T helper 2 （Th2）-predominance in saliva of oral lichen planus （OLP） patients and suggested a potential of salivary interleukin-4 （IL-4） as a biomarker for monitoring disease severity. To further determine the consistency of Th1/Th2 bias of OLP, this study investigated the expression profile of interferon-γ （IFN-γ） and IL-4 in serum and the relationship of the serum levels of these cytokines with their saliva partners. Sixty ethnic Chinese patients with OLP （40 of the erythematous/ulcerative form and 20 of the reticular form） were recruited for this study, with 40 age-sex-matched healthy volunteers as control group. IFN-γ and IL-4 levels in serum and paired saliva samples were screened by enzyme-linked immunosorbent assay. OLP patient showed a low-level IFN-γ but high-level IL-4 expression profile in both serum and saliva, with a lower IFN-γ/IL-4 ratio. Serum IL-4 level in the erythematous/ulcerative group was significantly higher than that in the reticular group. Serum levels of IFN-γ and IL-4 were significantly and positively correlated with their saliva partners. These results provided more evidence for Th2 cytokine- predominant immune imbalance in OLP, as well as the potential of IL-4 as the biomarker for monitoring severity of OLP.展开更多
Objective: To observe cyclooxygenase (COX)-2 expression in normal oral mucosa (NOM), oral lichen planus (OLP) and oral squamous cell carcinoma (OSCC) and explore its significance in the incidence of oral cancer. Metho...Objective: To observe cyclooxygenase (COX)-2 expression in normal oral mucosa (NOM), oral lichen planus (OLP) and oral squamous cell carcinoma (OSCC) and explore its significance in the incidence of oral cancer. Methods: The immunohistochemical method and RT-PCR method were applied to detect the expression of COX-2 and MMP-7 in 10 cases with NOM, 33 cases of with OLP and 38 cases with OSCC. Results: The expression of COX-2 mRNA in OSCC tissues (68.4%, 26/38) was significantly higher than in the OLP (24.2%, 8/33) and NOM (0.0%, 0/10) ( P<0.01). The expression of MMP-7 mRNA in OSCC tissues (65.8%, 25/38) was significantly higher than in the OLP (30.3%, 10/33) and NOM (0.0%, 0/10) ( P<0.01). The expression of MMP-7 in OLP was significantly higher than in the NOM ( P<0.05). There was no significant expression of COX-2 protein in NOM, and the positive rate was 42.4% (14/33) and 89.5% (34/38) in OLP and OSCC group, respectively. The COX-2 expression in cancer tissues was significantly higher than in NOM and OLP ( P<0.05). The MMP-7 protein expression in cancer tissues (84.2%, 32/38) was significantly higher than in NOM (10.0%, 1/10) and in OLP (42.4%, 14/33), and the positive rate in OLP was significantly higher than in NOM ( P<0.01). The COX-2 expression was associated with clinical stage ( P<0.05), the MMP-7 expression was associated with clinical stage and lymph node metastasis ( P<0.05). The expressions of COX-2 and MMP-7 mRNA were positively correlated with OSCC. Conclusions: The abnormal expressions of COX-2 and MMP-7 are closely related to the biological behavior of OSCC, the MMP-7 may be induced by COX-2, and further lead to the invasion and metastasis of OSCC.展开更多
Saxicolous species of lichens are able to induce and accelerate weathering of their rock substrate, and effects of lichens on substrate can be attributed to both physical and chemical causes. This paper is focused on ...Saxicolous species of lichens are able to induce and accelerate weathering of their rock substrate, and effects of lichens on substrate can be attributed to both physical and chemical causes. This paper is focused on biotic weathering actions of epilithic and endolithic species on the different rock types (sandstones and volcanogenic rocks) in Antarctica. The patterns, mechanisms, processes and neoformations of rock-weathering resulting from lichen colonization are expounded in detail. Furthermore, it is pointed out that, for a better understanding of the impacts of lichens on environments, the studies on the rate of biotic weathering and the comprehensive involvement of the lichen effects on weathering of natural rocks remain to be carried out in Antarctica.展开更多
A new depsidone, diffractione A （1）, as well as six known phenolic compounds （2-7） were isolated from Usnea diffracta. Their structures were elucidated by 1D and 2D NMR spectroscopy together with HRESIMS analysis....A new depsidone, diffractione A （1）, as well as six known phenolic compounds （2-7） were isolated from Usnea diffracta. Their structures were elucidated by 1D and 2D NMR spectroscopy together with HRESIMS analysis. All components were obtained for the first time from U. diffracta.展开更多
Oral lichen planus （OLP） is considered a T cell-mediated autoimmune disease with unknown aetiology. T helper cells appear to play an important role in the pathogenesis of OLP. We investigated the possible role of T ...Oral lichen planus （OLP） is considered a T cell-mediated autoimmune disease with unknown aetiology. T helper cells appear to play an important role in the pathogenesis of OLP. We investigated the possible role of T helper cells, Th1 and Th17, in the lesions and circulation of patients with OLP. Forty patients with OLP and 15 healthy volunteers were recruited. Double immunofluorescence staining was used to detect Th1 and Th17 cells in the OLP lesions, and intracellular cytokine staining and flow cytometry to evaluate the proportion of Th1 and Th17 cells in peripheral blood. The levels of serum interferon （IFN）-γ and interleukin （IL）-17 were assessed by using an enzyme-linked immunosorbent assay. It was found that Th17 cells, as well as Th1 cells, were present in OLP lesions. The proportion of peripheral Th1 and Th17 cells was significantly increased in patients with OLP. The proportion of Th17 cells in atrophic-erosive OLP was elevated as compared with that in reticular OLP. Serum IL-17 levels in OLP patients were significantly higher than in controls, and those in the atrophic-erosive OLP group were increased as compared with the reticular OLP group. However, the levels of serum IFN-γ were slightly decreased in OLP patients. Our data suggested that Th1 and Th17 cells in the local lesions and peripheral blood may be associated with the pathogenesis of OLP, and that IL-17 may be an important proinflammatory cytokine in OLP. These findings enhance our understanding of OLP pathogenesis.展开更多
Extrahepatic manifestations (EHMs) of hepatitis C virus (HCV) infection can affect a variety of organ systems with significant morbidity and mortality. Some of the most frequently reported EHM of HCV infection, involv...Extrahepatic manifestations (EHMs) of hepatitis C virus (HCV) infection can affect a variety of organ systems with significant morbidity and mortality. Some of the most frequently reported EHM of HCV infection, involve the oral region predominantly or exclusively. Oral lichen planus (OLP) is a chronic inflammatory condition that is potentially malignant and represents cell-mediated reaction to a variety of extrinsic antigens, altered self-antigens, or super antigens. Robust epidemiological evidence support the link between OLP and HCV. As the virus may replicate in the oral mucosa and attract HCV-specific T lymphocytes, HCV may be implicated in OLP pathogenesis. Sjögren syndrome (SjS) is an autoimmune exocrinopathy, characterized by dryness of the mouth and eyes and a multitude of other systemic signs and symptoms. SjS patients have also an increased risk of non-Hodgkin lymphoma. Patients with chronic hepatitis C do frequently have histological signs of Sjögren-like sialadenitis with mild or even absent clinical symptoms. However, it is still unclear if HCV may cause a disease mimicking SjS or it is directly responsible for the development of SjS in a specific subset of patients. Oral squamous cell carcinoma is the most common oral malignant tumour and at least in some part of the world could be linked to HCV.展开更多
基金supported by the Technology Agency of the Czech Republic(Grant Nos.SS01010270,SS06010420)by a long-term research development grant RVO(Grant No.67985939)。
文摘Sequencing of environmental samples has great potential for biodiversity research,but its application is limited by the lack of reliable DNA barcode databases for species identifications.Such a database has been created for epiphytic lichens of Europe,allowing us to compare the results of environmental sequencing with standard taxonomic surveys.The species undetected by taxonomic surveys(what we term the ghost component)amount to about half of the species actually present in hectare plots of Central European forests.Some of these,which currently occur only as diaspores or weakly developed thalli,are likely to be favoured in the course of global change.The ghost component usually represents a larger fraction in managed forests than in old-growth unmanaged forests.The total species composition of different plots is much more similar than suggested by taxonomic surveys alone.On a regional scale,this supports the well-known statement that“everything is everywhere,but,the environment selects”.
基金supported by the MITACS Accelerate grant with Greenfirst,industry partner in La Sarre,QC,Canada.
文摘Fire disturbances are increasing under global climate change and ecological transformations of forests are occurring.Specifically,shifts from productive closed-canopy feather moss forests to low-productivity open-canopy lichen(Cladonia spp.)woodlands have been observed in boreal forests of eastern Canada.It has been hypothesized that high severity of fires would be the cause of this change,but this is difficult to validate a posteriori on mature forest stands.Because charcoal properties are affected by fire severity,we have put forward the hypothesis that the amount and physicochemical properties of charcoal(C,N,H,O,ash,surface area)would be different and indicative of a greater fire severity for open-canopy forests compared to closed canopy ones.Our hypothesis was partly validated in that the amount of charcoal found on the ground of closed-canopy forests was greater than that of open-canopy forests.However,the physicochemical properties were not different,albeit a greater variability of charcoal properties for open canopy stands.These results do not allow us to fully validate or reject our hypothesis on the role of fire severity in the shift between open and closed canopy stands.However,they suggest that the variability in fire conditions as well as the amounts of charcoal produced are different between the two ecosystem types.Furthermore,considering the role that biochar may play in improving soil conditions and promoting vegetation restoration,our results suggest that charcoal may play a role in maintaining these two stable alternative ecosystem states.
基金carried out within the framework of the most important innovative project of state importance“Development of a system of ground-based and remote monitoring of carbon pools and greenhouse gas fluxes on the territory of the Russian Federation,…”(No.123030300031-6)in the northern taiga subzone and on the border of tundra and taiga under the state assignment of the Forest Institute of the Karelian Research Center of the Russian Academy of Sciences(FMEN-2021-0018)with the partial financial support from RSF(grant no.21-14-00204)。
文摘Background:The heartwood(HW)proportion in the trunk of mature trees is an important characteristic not only for wood quality but also for assessing the role of forests in carbon sequestration.We have for the first time studied the proportion of HW in the trunk and the distribution of carbon and extractives in sapwood(SW)and HW of 70–80 year old Pinus sylvestris L.trees under different growing conditions in the pine forests of North-West Russia.Method:We have examined the influence of conditions and tree position in stand(dominant,intermediate and suppressed trees)in the ecological series:blueberry pine forest(Blu)–lingonberry pine forest(Lin)–lichen pine forest(Lic).We have analyzed the influence of climate conditions in the biogeographical series of Lin:the middle taiga subzone–the northern taiga subzone–the transition area of the northern taiga subzone and tundra.Results:We found that the carbon concentration in HW was 1.6%–3.4%higher than in SW,and the difference depended on growing conditions.Carbon concentration in HW increased with a decrease in stand productivity(Blu-Lin-Lic).In medium-productive stands,the carbon concentration in SW was higher in intermediate and supressed trees compared to dominant trees.In the series from south to north,carbon concentration in HW increased by up to 2%,while in SW,it rose by 2.7%–3.8%.Conclusions:Our results once again emphasized the need for an empirical assessment of the accurate carbon content in aboveground wood biomass,including various forest growing conditions,to better understand the role of boreal forests in carbon storage.
基金the National Key Laboratory of Oral Disease Prevention and Treatment of Open Subject Project(SKLOD2024OF04)Luzhou City Science and Technology Plan Project(2023RCX171)Sichuan Province Medical Research Project Program(S23043)。
文摘Decorin(DCN)is primarily found in the connective tissues of various parts of the body,including the lungs,kidneys,bone tissue,aorta,and tendons.It is an important component of the extracellular matrix(ECM)and belongs to the class I small leucine-rich proteoglycans family.DCN is increasingly attracting attention due to its significant role in tumors,fibrotic diseases,and the regulation of vascular formation.Moreover,its anti-tumor properties have positioned it as a promising biomarker in the fight against cancer.Numerous studies have confirmed that DCN can exert inhibitory effects in various solid tumors,particularly in oral squamous cell carcinoma(OSCC),by activating its downstream pathways through binding with the epidermal growth factor receptor(EGFR)and mesenchymal-epithelial transition(MET)receptor,or by stabilizing and enhancing the expression of the tumor suppressor gene p53 to mediate apoptosis in cancer cells that have undergone mutation.The occurrence of OSCC is a continuous and dynamic process,encompassing the transition from normal mucosa to oral potentially malignant disorders(OPMDs),and further progressing from OPMDs to the malignant transformation into OSCC.We have found that DCN may exhibit a bidirectional effect in the progression of oral mucosal carcinogenesis,showing a trend of initial elevation followed by a decline,which decreases with the differentiation of OSCC.In OPMDs,DCN exhibits high expression and may be associated with malignant transformation,possibly linked to the increased expression of P53 in OPMDs.In OSCC,the expression of DCN is reduced,which can impact OSCC angiogenesis,and inhibit tumor cell proliferation,migration,and invasion capabilities,serving as a potential marker for predicting adverse prognosis in OSCC patients.This article reviews the current research status of DCN,covering its molecular structure,properties,and involvement in the onset and progression of oral mucosal carcinogenesis.It elucidates DCN’s role in this process and aims to offer insights for future investigations into its mechanism of action in oral mucosal carcinogenesis and its potential application in the early diagnosis and treatment of OSCC.
基金supported by CAMS Innovation Fund for Medical Sciences(Grant no.2021-I2M-1-055)National Microbial Resource Center(Grant no.NMRC-2023-3).
文摘Lichens,as dual organisms comprising a major mycobiont and a major photobiont,exhibit remarkable survival capabilities in extreme conditions,such as those found in Antarctica.Despite their adaptability,the diversity and distribution of lichen photobionts in the ice-free areas of maritime Antarctica remain less understood compared to their mycobiont counterparts.In our study,we investigated the diversity of both lichen mycobionts and photobionts in 56 samples collected from the Fildes Region on King George Island,maritime Antarctica.Through sequencing of the nuclear ribosomal internal transcribed spacer regions and subsequent phylogenetic analysis,we examined the relationships and association patterns between mycobionts and photobionts.Our findings revealed 19 taxa of lichen mycobionts across 13 families and seven orders,along with nine photobiont species within the class Trebouxiophyceae.These photobionts encompassed six Trebouxia species,one Asterochloris species,one Chloroidium species,and one Stichococcus species.In particular,a new Trebouxia lineage(Trebouxia sp.OTU D08)and a new Chloroidium lineage were found.The analysis indicated that many mycobionts could be associated with multiple photobiont species,a pattern also observed among the photobionts.These results contribute significantly to our understanding of the complex diversity of lichen mycobionts and photobionts in the ice-free areas of maritime Antarctica.
基金Doctoral Research Startup Grant at Southwest Forestry CollegeThe Chinese Academy of Science(KSCX2-1-03)
文摘Faeces were counted along horizontal, 5.0m wide strips at altitude intervals of 100m to examine the altitudinal ranging pattern of a band of black-and-white snub-nosed monkeys （Rhinopithecus bieti） at Nanren （99°04′E, 28°34′N, Baima Snow Mountain Nature Reverse, Yunnan, China） at four areas in each season between 2000-2001. Faeces were also counted along vertical, 2.5 m wide strips in one subvalley and on one subridge in each area. Monkeys used an altitudinal range of 3500-4300m, but preferred occupying the upper forest belt between 3900 and 4200m asl year-round, being at the highest altitude in summer, the lowest altitude in spring, and middle altitudes between autumn and winter （lower in winter than autumn）. Moreover, there were secondary peaks of lower altitude use （3700m） in spring and winter. In addition, more faeces were distributed in subvalleys than on subridges in winter, this suggests that monkeys tend to spend more time in subvalleys where there is less wind and fluctuating temperatures. The significant correlation between faecal density and lichen load might indicate that altitudinal distribution of food resources may act as an important factor affecting the monkeys＇ range. The monkeys might migrate to lower altitudes to eat young sprouts and leaves in spring, and to shelter from snowstorms in winter, possibly resulting in the secondary peaks at lower altitudes.
基金National Natural Science Foundation of China(Grant No.91029711)
文摘Oral lichen planus （OLP） is a chronic inflammatory disorder and premalignantlesion, of which the mechanisms are still obscure. In the present study, the expression levels of miR-96/182/183 cluster, miR-203, miR-375, and miR-769-5p in both tissues and exfoliative cells of OLP patients as well as healthy volunteers were detected, differentially expressed miRNAs were identified and their correlation with OLP was evaluated by a biplot method. Experimental results show that miR-203 is significantly up-regulated in patient lesion tissues in comparison to volunteer mucosa tissues. Moreover, the contra- dictory insignificant expression changes of miR-203 as well as miR-96/182/183 cluster in comparisons of exfoliative cell samples suggest that different cell compositions in OLP lesion have distinct miRNA regulation, which accords with the histological heterogeneity of OLP. Finally, biplot analyses indicate the expression of miR-203 and miR-96/182/183 cluster are positively correlated in patient lesions. These results provide miR-203 as a molecular indicator of heterogeneity of OLP, and also a potential diagnostic biomarker or therapeutic target that deserves further studies.
基金supported by the National Natural Science Foundation of China (Nos. 31170464, 41573111, and 31300322)
文摘Biological soil crusts(BSCs)have important ecological functions in arid and semiarid lands,but they remain poorly understood in terms of the changes in microbial communities during BSC succession under in situ field conditions.Here,454 pyrosequencing was used to assess the microbial community composition of four BSC types in the Tengger Desert of China:alga,lichen(cyanolichen and green alga-lichen),and moss crusts,representing early,middle,and final successional stages of BSCs,respectively.The results showed the highest diversity of microbial communities inhabiting lichen crusts,whereas the lowest diversity was observed in moss crusts.Five phyla,Proteobacteria,Actinobacteria,Cyanobacteria,Bacteroidetes,and Acidobacteria,accounted for about 72% to 87%of total prokaryotic sequences in different BSCs.The most abundant eukaryotic microorganism was Ascomycota,accounting for 47%to 93%of the total eukaryotic sequences.Along the succession of BSCs,the abundance of photoautotrophic Cyanobacteria,Chlorophyta,and Bacillariophyta declined,and that of heterotrophic microorganisms such as bacteria and fungi increased.Statistical analysis showed clear divergency of microbial taxa at the class level among the different successional stages of BSCs.The clustering results at class level showed that the moss crusts were the farthest from the rest in prokaryotic composition;the alga crusts were the most different in terms of eukaryotic microorganisms and the two kinds of lichen crusts were relatively closer in both compositions.Ordination analysis showed that the main variations of community structure among BSCs could be explained best by the abundance of Cyanobacteria and Ascomycota and by physiochemical properties of BSCs,including mechanical composition,moisture,and electrical conductivity.In conclusion,our results indicate that Cyanobacteria and Ascomycota likely play an important role in the evolution of BSC structure and functions and highlight the importance of environmental factors in shaping microbial community structures of BSCs in the Tengger Desert of China.
文摘Crustose lichens are distributed extensively in karst areas in Southern China. They can be found on the surface of carbonate rocks. Through biophysical and biochemical processes, crustose lichens reform the subsurface of carbonate rocks and in the meanwhile change their physical and chemical properties: (1) the mechanical strength decreases by 17.04° on average (up to 33.2°); (2) the chemical solution surface area increases from 28.26% to 75.36% (lichen microholes considered only); and (3) the water-holding capacity is greatly improved. Comparative field experiments between biokarst samples underneath crustose lichens and fresh rock samples with the same composition and texture show that the corrosional rate of carbonate rocks of the former is 1.264–1.643 times higher than that of the latter. Crustose lichens are considered as an activator of the surface corrosion of carbonate rocks.
基金project support from the Turkey Scientific and Technological Research Council (project no. 106S340)Selcuk University Coordination of Scientific Research (project no. 06202034)supported by Open Fund of State Key Laboratory of Oral Diseases, Sichuan University
文摘Oral lichen planus （OLP） is a chronic inflammatory disease that is frequently detected in oral tissues. The aim of our study was to identify the prevalence of the detection of periodontopathogenic microorganisms （Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia and Treponema denticola in OLP patients and to compare with this prevalence of periodontopathogenic microorganisms in healthy non-OLP patients. Our study included 27 （18 chronic periodontitis （OLPP） and 9 gingivitis （OLPG）） patients diagnosed with OLP along with 26 （13 chronic periodontitis （HP） and 13 gingivitis （HG）） healthy non-OLP patients. The multiplex polymerase chain reaction （PCR）with subsequent reverse hybridization method （micro-IDent） was used for identifying periodontopathogenic microorganisms present in subgingival plaque samples. The percentages of detection for A. actinomycetemcomitans, P. gingivalis, P. intermedia, T. forsythia and T. denticola in subgingival plaque samples taken from OLP patients （OLPG and OLPP） were 18.5%, 85.1%, 81.4%, 88.8% and 74%, respectively. Meanwhile, in the non-OLP patients （HG and HP）, these values were 7.6%, 50%, 46.1%, 73% and 57.7%, respectively. Thus, comparing the non-OLP groups with the OLP groups, the periodontopathogens＇ percentages of detection in the OLP groups were higher than those in the non-OLP groups. According to our study results, OLP patients have higher levels of infection with A. actinomycetemcomitans, P. gingivalis, P. intermedia, T. forsythia and T. denticola than non-OLP patients. We argue that the high percentages in patients with OLP may help identify the importance of periodontopathoRenic microorganisms in the progress of periodontal diseases of OLP.
基金supported by grants from the National Natural Science Foundation of China (No. 30930100, 81072218, 81200791, 81321002 and 81300882)the Doctoral Program of the Ministry of Education of China (No. 20110181110055 and 20120181120011)Natural Science Foundation of Chongqing (No. cstc2013jcyjA10042)
文摘Our previous salivary study had demonstrated an apparent T helper 2 （Th2）-predominance in saliva of oral lichen planus （OLP） patients and suggested a potential of salivary interleukin-4 （IL-4） as a biomarker for monitoring disease severity. To further determine the consistency of Th1/Th2 bias of OLP, this study investigated the expression profile of interferon-γ （IFN-γ） and IL-4 in serum and the relationship of the serum levels of these cytokines with their saliva partners. Sixty ethnic Chinese patients with OLP （40 of the erythematous/ulcerative form and 20 of the reticular form） were recruited for this study, with 40 age-sex-matched healthy volunteers as control group. IFN-γ and IL-4 levels in serum and paired saliva samples were screened by enzyme-linked immunosorbent assay. OLP patient showed a low-level IFN-γ but high-level IL-4 expression profile in both serum and saliva, with a lower IFN-γ/IL-4 ratio. Serum IL-4 level in the erythematous/ulcerative group was significantly higher than that in the reticular group. Serum levels of IFN-γ and IL-4 were significantly and positively correlated with their saliva partners. These results provided more evidence for Th2 cytokine- predominant immune imbalance in OLP, as well as the potential of IL-4 as the biomarker for monitoring severity of OLP.
基金supported by Jinan Science and Technology Development Plans Grant (No.201121040)
文摘Objective: To observe cyclooxygenase (COX)-2 expression in normal oral mucosa (NOM), oral lichen planus (OLP) and oral squamous cell carcinoma (OSCC) and explore its significance in the incidence of oral cancer. Methods: The immunohistochemical method and RT-PCR method were applied to detect the expression of COX-2 and MMP-7 in 10 cases with NOM, 33 cases of with OLP and 38 cases with OSCC. Results: The expression of COX-2 mRNA in OSCC tissues (68.4%, 26/38) was significantly higher than in the OLP (24.2%, 8/33) and NOM (0.0%, 0/10) ( P<0.01). The expression of MMP-7 mRNA in OSCC tissues (65.8%, 25/38) was significantly higher than in the OLP (30.3%, 10/33) and NOM (0.0%, 0/10) ( P<0.01). The expression of MMP-7 in OLP was significantly higher than in the NOM ( P<0.05). There was no significant expression of COX-2 protein in NOM, and the positive rate was 42.4% (14/33) and 89.5% (34/38) in OLP and OSCC group, respectively. The COX-2 expression in cancer tissues was significantly higher than in NOM and OLP ( P<0.05). The MMP-7 protein expression in cancer tissues (84.2%, 32/38) was significantly higher than in NOM (10.0%, 1/10) and in OLP (42.4%, 14/33), and the positive rate in OLP was significantly higher than in NOM ( P<0.01). The COX-2 expression was associated with clinical stage ( P<0.05), the MMP-7 expression was associated with clinical stage and lymph node metastasis ( P<0.05). The expressions of COX-2 and MMP-7 mRNA were positively correlated with OSCC. Conclusions: The abnormal expressions of COX-2 and MMP-7 are closely related to the biological behavior of OSCC, the MMP-7 may be induced by COX-2, and further lead to the invasion and metastasis of OSCC.
基金National Natural Science Foundation of China No.40001011
文摘Saxicolous species of lichens are able to induce and accelerate weathering of their rock substrate, and effects of lichens on substrate can be attributed to both physical and chemical causes. This paper is focused on biotic weathering actions of epilithic and endolithic species on the different rock types (sandstones and volcanogenic rocks) in Antarctica. The patterns, mechanisms, processes and neoformations of rock-weathering resulting from lichen colonization are expounded in detail. Furthermore, it is pointed out that, for a better understanding of the impacts of lichens on environments, the studies on the rate of biotic weathering and the comprehensive involvement of the lichen effects on weathering of natural rocks remain to be carried out in Antarctica.
基金supported by the National 863 Program of China(No.2007AA09Z403)National Key Technology Research and Development Program of China(No.2007BAI37B05)Natural Science Foundation of Gansu Province(No.0710RJZA120).
文摘A new depsidone, diffractione A （1）, as well as six known phenolic compounds （2-7） were isolated from Usnea diffracta. Their structures were elucidated by 1D and 2D NMR spectroscopy together with HRESIMS analysis. All components were obtained for the first time from U. diffracta.
文摘Oral lichen planus （OLP） is considered a T cell-mediated autoimmune disease with unknown aetiology. T helper cells appear to play an important role in the pathogenesis of OLP. We investigated the possible role of T helper cells, Th1 and Th17, in the lesions and circulation of patients with OLP. Forty patients with OLP and 15 healthy volunteers were recruited. Double immunofluorescence staining was used to detect Th1 and Th17 cells in the OLP lesions, and intracellular cytokine staining and flow cytometry to evaluate the proportion of Th1 and Th17 cells in peripheral blood. The levels of serum interferon （IFN）-γ and interleukin （IL）-17 were assessed by using an enzyme-linked immunosorbent assay. It was found that Th17 cells, as well as Th1 cells, were present in OLP lesions. The proportion of peripheral Th1 and Th17 cells was significantly increased in patients with OLP. The proportion of Th17 cells in atrophic-erosive OLP was elevated as compared with that in reticular OLP. Serum IL-17 levels in OLP patients were significantly higher than in controls, and those in the atrophic-erosive OLP group were increased as compared with the reticular OLP group. However, the levels of serum IFN-γ were slightly decreased in OLP patients. Our data suggested that Th1 and Th17 cells in the local lesions and peripheral blood may be associated with the pathogenesis of OLP, and that IL-17 may be an important proinflammatory cytokine in OLP. These findings enhance our understanding of OLP pathogenesis.
文摘Extrahepatic manifestations (EHMs) of hepatitis C virus (HCV) infection can affect a variety of organ systems with significant morbidity and mortality. Some of the most frequently reported EHM of HCV infection, involve the oral region predominantly or exclusively. Oral lichen planus (OLP) is a chronic inflammatory condition that is potentially malignant and represents cell-mediated reaction to a variety of extrinsic antigens, altered self-antigens, or super antigens. Robust epidemiological evidence support the link between OLP and HCV. As the virus may replicate in the oral mucosa and attract HCV-specific T lymphocytes, HCV may be implicated in OLP pathogenesis. Sjögren syndrome (SjS) is an autoimmune exocrinopathy, characterized by dryness of the mouth and eyes and a multitude of other systemic signs and symptoms. SjS patients have also an increased risk of non-Hodgkin lymphoma. Patients with chronic hepatitis C do frequently have histological signs of Sjögren-like sialadenitis with mild or even absent clinical symptoms. However, it is still unclear if HCV may cause a disease mimicking SjS or it is directly responsible for the development of SjS in a specific subset of patients. Oral squamous cell carcinoma is the most common oral malignant tumour and at least in some part of the world could be linked to HCV.
