High microsatellite instability(MSI-H)colorectal cancer(CRC),caused by deficient mismatch repair,accounts for about 15%of all CRC cases and is more common in right-sided tumors.While early-stage MSI-H CRC has a relati...High microsatellite instability(MSI-H)colorectal cancer(CRC),caused by deficient mismatch repair,accounts for about 15%of all CRC cases and is more common in right-sided tumors.While early-stage MSI-H CRC has a relatively good prognosis,advanced cases often respond poorly to standard chemotherapy.Immune checkpoint inhibitors,such as pembrolizumab,have shown strong and lasting effects in MSI-H CRC.Pembrolizumab is now approved as a first-line treatment for metastatic MSI-H CRC due to its superior outcomes compared to traditional chemotherapy.CASE SUMMARY A 44-year-old male with MSI-H transverse colon cancer presented with hematochezia,abdominal pain,and significant weight loss.Imaging revealed a bulky tumor with invasion of adjacent structures and multiple liver lesions.A diverting ileostomy was performed followed by 36 cycles of pembrolizumab.The patient achieved a clinical and radiologic complete response.One month after completing the treatment,the patient underwent laparoscopic right hemicolectomy.A spontaneous transection of the colon at the original tumor site was unexpectedly identified.Final pathology confirmed pathological complete response(ypT0N0)with fibrosis.The patient recovered well after surgery,and follow-up showed no evidence of recurrence.CONCLUSION Immune checkpoint inhibitors may cause delayed structural damage to bowel tissue even after apparent complete tumor regression.展开更多
In adult mammals,optic nerve injury leads to irreversible vision loss due to its extremely limited regenerative capacity.In contrast,adult zebrafish possess a robust capacity for spontaneous visual system regeneration...In adult mammals,optic nerve injury leads to irreversible vision loss due to its extremely limited regenerative capacity.In contrast,adult zebrafish possess a robust capacity for spontaneous visual system regeneration,although the spatiotemporal coordination of recovery across the retina,optic nerve,and brain remains poorly understood.In the present study,the regenerative dynamics following optic nerve transection were systematically characterized in adult zebrafish over a 5 week period using hematoxylin-eosin staining,immunohistochemistry,transmission electron microscopy,single-cell RNA sequencing,and optokinetic response(OKR)behavioral assessments.At 1 week post-injury(1 wpi),retinal ganglion cell depletion was evident but showed significant recovery by 2 wpi.Concurrently,the injured optic nerve displayed a marked increase in diameter and cell number at 2 wpi,including widespread expression of proliferating cell nuclear antigen,consistent with heightened proliferative activity.Single-cell transcriptomic profiling at 2 wpi revealed five principal cell populations:fibroblasts,mural cells,immune cells,mature oligodendrocytes,and myelin-forming oligodendrocytes.By 4-5 wpi,remyelination within the optic nerve and re-establishment of synaptic architecture in the optic tectum were strongly correlated with functional restoration of OKR behavior.These findings provide a comprehensive spatiotemporal framework of visual pathway regeneration in zebrafish,establishing a valuable model for elucidating conserved mechanisms of neural repair with translational potential for human vision restoration.展开更多
Functional recovery in penetrating neurological injury is hampered by a lack of clinical regenerative therapies.Biomaterial therapies show promise as medical materials for neural repair through immunomodulation,struct...Functional recovery in penetrating neurological injury is hampered by a lack of clinical regenerative therapies.Biomaterial therapies show promise as medical materials for neural repair through immunomodulation,structural support,and delivery of therapeutic biomolecules.However,a lack of facile and pathology-mimetic models for therapeutic testing is a bottleneck in neural tissue engineering research.We have deployed a two-dimensional,high-density multicellular cortical brain sheet to develop a facile model of injury(macrotransection/scratch wound)in vitro.The model encompasses the major neural cell types involved in pathological responses post-injury.Critically,we observed hallmark pathological responses in injury foci including cell scarring,immune cell infiltration,precursor cell migration,and shortrange axonal sprouting.Delivering test magnetic particles to evaluate the potential of the model for biomaterial screening shows a high uptake of introduced magnetic particles by injury-activated immune cells,mimicking in vivo findings.Finally,we proved it is feasible to create reproducible traumatic injuries in the brain sheet(in multielectrode array devices in situ)characterized by focal loss of electrical spiking in injury sites,offering the potential for longer term,electrophysiology plus histology assays.To our knowledge,this is the first in vitro simulation of transecting injury in a two-dimensional multicellular cortical brain cell sheet,that allows for combined histological and electrophysiological readouts of damage/repair.The patho-mimicry and adaptability of this simplified model of brain injury could benefit the testing of biomaterial therapeutics in regenerative neurology,with the option for functional electrophysiological readouts.展开更多
目的比较采用毛囊单位钻取术(follicular unit excision,FUE)喇叭口针和锐针钻取毛囊的临床效果。方法回顾性分析自2024年10月至2025年5月,南方医科大学南方医院进行毛发移植49例患者的临床资料。采用FUE喇叭口针钻取毛囊的患者25例,采...目的比较采用毛囊单位钻取术(follicular unit excision,FUE)喇叭口针和锐针钻取毛囊的临床效果。方法回顾性分析自2024年10月至2025年5月,南方医科大学南方医院进行毛发移植49例患者的临床资料。采用FUE喇叭口针钻取毛囊的患者25例,采用FUE锐针钻取毛囊患者24例。通过查询每例患者供区毛囊钻取情况(包括毛囊钻取时间、毛囊钻取总量及毛囊离断率等)、随访期间供区恢复和并发症情况等,综合分析采用FUE喇叭口针和FUE锐针钻取毛囊的临床效果。结果FUE喇叭口针和FUE锐针组患者中,毛囊的平均钻取总量分别为(5380±237)根毛囊和(5540±204)根毛囊,平均钻取时间分别为(89±23)min和(93±28)min,差异均无统计学意义(P>0.05);平均离断率分别为(4.37±0.31)%和(7.02±0.39)%,差异有统计学意义(P<0.05)。FUE喇叭口针组和FUE锐针组患者供区术后恢复时间均为(3±1)d,并发症发生率差异无统计学意义(P>0.05),术后两组间毛发生长情况无明显差异。结论FUE喇叭口针钻取毛囊具有离断率较低的特点,能够减少毛囊损伤,值得临床推广。展开更多
An improved Carnegie Ames Stanford Approach model (CASA model) was used to estimate the net primary productivity (NPP) of the Northeast China Transect (NECT) every month from 1982 to 2000. The spatial-temporal d...An improved Carnegie Ames Stanford Approach model (CASA model) was used to estimate the net primary productivity (NPP) of the Northeast China Transect (NECT) every month from 1982 to 2000. The spatial-temporal distribution of NPP along NECT and its response to climatic change were also analyzed. Results showed that the change tendency of NPP spatial distribution in NECT is quite similar to that of precipitation and their spatial correlation coefficient is up to 0.84 (P 〈 0.01). The inter-annual variation of NPP in NECT is mainly affected by the change of the aestival NPP every year, which accounts for 67.6% of the inter-annual increase in NPP and their spatial correlation coefficient is 0.95 (P 〈 0.01). The NPP in NECT is mainly cumulated between May and September, which accounts for 89.8% of the annual NPP. The NPP in summer (June to August) accounts for 65.9% of the annual NPP and is the lowest in winter. Recent climate changes have enhanced plant growth in NECT. The mean NPP increased 14.3% from 1980s to 1990s. The inter-annual linear trend of NPP is 4.6 gC·m^-2·a^-1, and the relative trend is 1.17%, which owns mainly to the increasing temperature.展开更多
The 16 tree species on Northeast China Transect (NECT) were analyzed from the change of geographical distribution, frequency and dominance pattern and the spatial correlation at landscape scale in 1986 and 1994. Pin...The 16 tree species on Northeast China Transect (NECT) were analyzed from the change of geographical distribution, frequency and dominance pattern and the spatial correlation at landscape scale in 1986 and 1994. Pinus koraiensis Sieb. et Zucc. and Fraxinus rhynchophylla Hemsl. had spread rapidly towards west and east, respectively. The frontier form of species had close relation with its movement. The patch size of Pinus koraiensis , Populus davidiana Dode., Phellodendron amurense Rupr., Juglans mandshurica Maxim., Fraxinus mandshurica Rupr., Betula dahurica Pall., Picea koraiensis Nakai, Abies nephrolepis Maxim. and Larix olgeusis var. koreana Nakai decreased, however, Quercus mongolica Fisch., Betula costata Trautv., Acer mono Maxim., Tilia spp., Ulmus spp., Betula platyphylla Suk. and Fraxinus rhynchophylla increased. The frequency pattern of Populus davidiana , Betula platyphylla , Fraxinus rhynchophylla and Betula dahurica changed significantly. The dominance pattern of Populus davidiana , Tilia spp., Juglans mandshurica , Betula platyphylla , Betula dahurica and Abies nephrolepis changed significantly. The spatial correlation between Quercus mongolica and Betula dahurica , Betula costata and Picea spp., Betula costata and Abies nephrolepis , Picea spp. and Abies nephrolepis declined, however, the spatial correlation between Larix spp. and Betula platyphylla , Acer mono and Ulmus spp. increased.展开更多
Net photosynthesis ( P n ), transpiration ( E ), stomatal conductance ( g s) and water use efficiency (WUE) of more than 218 species belonging to two different reproductive functional types, i.e. clonal (115 ...Net photosynthesis ( P n ), transpiration ( E ), stomatal conductance ( g s) and water use efficiency (WUE) of more than 218 species belonging to two different reproductive functional types, i.e. clonal (115 species) and non_clonal species (103 species), along the 1 670 km Northeast China Transect (NECT) were analyzed. The results showed that P n and WUE appeared to be lower in the east and west ends of NECT, with peaks in the middle. Transpiration was found to be higher in the west end, where most temperate desert species were distributed. On the same site, most clonal species showed higher P n and related physiological variables than non_clonal species. For different growth forms over NECT, e.g. forest trees, shrubs and grasses, meadow steppe shrubs and grasses, typical steppe shrubs and grasses, the meadow steppe and typical steppe grasses, showed higher values of physiological variables than the forest or the desert species. But for the two reproductive plant functional types (PFTs), clonal species had higher physiological variables, with averages of 22%, 15%, 23% and 14% higher than the non_clonal ones for P n , E, g s, and WUE, respectively. Such differences indicated that clonal species might have advantages over non_clonal species in utilizing environmental resources such as light, CO 2, and especially water.展开更多
The effective lithospheric elastic thickness of the continent is an important parameter for examination of the large-scale structure and analyses of the mechanism of isostatic compensation within the plate, and a para...The effective lithospheric elastic thickness of the continent is an important parameter for examination of the large-scale structure and analyses of the mechanism of isostatic compensation within the plate, and a parameter standing for the strength of the lithosphere. The Te values along Quanzhou-Heishui, the southeast section of the Arctic Ocean-Eurasian Continent-Pacific Ocean geoscience transect, are estimated by using the coherence technique developed by Forsyth. Studies of the feature of the coherence between gravity and topography suggest that at short wavelengths (6. 6-100 km) for each data box that is used to estimate Te, the plate is strong enough to support topographic loads and gravity and topography are uncorrelated. At long wavelengths where the plate is deflected by surface and subsurface loads are compensated by the flexure model. Sichuan land-stone with low heat-flow values has high Te values whereas in Ninghua, Datian, land-stone with high heat-flow values has low Te values, which reflects a correlation, low heat-flow values corresponding to high Te values and high heat-flow values corresponding to low Te values. Te values can be divided into two sections: northwest high section and southeast low section. There is roughly a positive correlation between crustal thickness and effective elastic thickness of the lithosphere.展开更多
Livelihoods of farmers and nomads in Tibetan Plateau are severely affected by grassland and herbal resources degeneration. How to help them achieve livelihood diversi- fication is a key sustainable development issue. ...Livelihoods of farmers and nomads in Tibetan Plateau are severely affected by grassland and herbal resources degeneration. How to help them achieve livelihood diversi- fication is a key sustainable development issue. This paper examines livelihood assets, live- lihood diversification level and livelihood strategies of farmers and nomads in 3 regions of eastern transect in Tibetan Plateau. The results show that livelihood diversification is a popular strategy. From high mountain gorge region to mountain plateau region and plateau region, livelihood diversification level is reduced, and livelihood activities and proportion of extended livelihood also decrease. Livelihood assets and livelihood diversification level decrease with the increase of elevation, mainly shown in human assets and natural assets. Livelihood diversification level is highly correlative with livelihood assets, mainly shown in natural assets, human assets and social assets. Livelihood improvement strategies of farmers and nomads are still based on existing livelihood assets, mainly raising livestock and digging herbs, and less farmers and nomads consider off-farm employment or doing business. Nomads in plateau region should learn much from experiences of extended livelihoods of people in high mountain gorge region and mountain plateau region. Therefore, aids of governments should focus on relieving restricted factors of livelihood diversification and help them improve their abilities to build up extended type livelihoods.展开更多
Our previous studies revealed that etomidate, a non-barbiturate intravenous anesthetic agent, has protective effects on retinal ganglion cells within 7 days after optic nerve transection. Whether this process is relat...Our previous studies revealed that etomidate, a non-barbiturate intravenous anesthetic agent, has protective effects on retinal ganglion cells within 7 days after optic nerve transection. Whether this process is related to anti-oxidative stress is not clear. To reveal its mechanism, we established the optic nerve transection injury model by transecting 1 mm behind the left eyeball of adult male Sprague-Dawley rats. The rats received an intraperitoneal injection of etomidate(4 mg/kg) once per day for 7 days. The results showed that etomidate significantly enhanced the number of retinal ganglion cells retrogradely labeled with Fluorogold at 7 days after optic nerve transection. Etomidate also significantly reduced the levels of nitric oxide and malonaldehyde in the retina and increased the level of glutathione at 12 hours after optic nerve transection. Thus, etomidate can protect retinal ganglion cells after optic nerve transection in adult rats by activating an anti-oxidative stress response. The study was approved by the Animal Ethics Committee at Air Force Medical University, China(approval No. 20180305) on March 5, 2018.展开更多
From July 2008 to August 2008, 72 leaf samples from 22 species and 81 soil samples in the nine natural forest ecosystems were collected, from north to south along the North-South Transect of Eastern China (NSTEC). B...From July 2008 to August 2008, 72 leaf samples from 22 species and 81 soil samples in the nine natural forest ecosystems were collected, from north to south along the North-South Transect of Eastern China (NSTEC). Based on these samples, we studied the geographical distribution patterns of vegetable water use efficiency (WUE) and nitrogen use efficiency (NUE), and analyzed their relationship with environmental factors. The vegetable WUE and NUE were calculated through the measurement of foliar δ 13C and C/N of predominant species, respectively. The results showed: (1) vegetable WUE, ranging from 2.13 to 28.67 mg C g-1 H2O, increased linearly from south to north in the representative forest ecosystems along the NSTEC, while vegetable NUE showed an opposite trend, increasing from north to south, ranging from 12.92 to 29.60 g C g-1 N. (2) Vegetable WUE and NUE were dominantly driven by climate and significantly affected by soil nutrient factors. Based on multiple stepwise regression analysis, mean annual temperature, soil phosphorus concentration, and soil nitrogen concentration were responding for 75.5% of the variations of WUE (p0.001). While, mean annual precipitation and soil phosphorus concentration could explain 65.7% of the change in vegetable NUE (p0.001). Moreover, vegetable WUE and NUE would also be seriously influenced by atmospheric nitrogen deposition in nitrogen saturated ecosystems. (3) There was a significant trade-off relationship between vegetable WUE and NUE in the typical forest ecosystems along the NSTEC (p0.001), indicating a balanced strategy for vegetation in resource utilization in natural forest ecosystems along the NSTEC. This study suggests that global change would impact the resource use efficiency of forest ecosystems. However, vegetation could adapt to those changes by increasing the use efficiency of shortage resource while decreasing the relatively ample one. But extreme impacts, such as heavy nitrogen deposition, would break this trade-off mechanism and give a dramatic disturbance to the ecosystem biogeochemical cycle.展开更多
Long non-coding RNAs(lncRNAs)are abundantly expressed in the central nervous system and exert a critical role in gene regulation via multiple biological processes.To uncover the functional significance and molecular m...Long non-coding RNAs(lncRNAs)are abundantly expressed in the central nervous system and exert a critical role in gene regulation via multiple biological processes.To uncover the functional significance and molecular mechanisms of lncRNAs in spinal cord injury(SCI),the expression signatures of lncRNAs were profiled using RNA sequencing(RNA-seq)technology in a Sprague-Dawley rat model of the 10th thoracic vertebra complete transection SCI.Results showed that 116 of 14,802 detected lncRNAs were differentially expressed,among which 16—including eight up-regulated(H19,Vof16,Hmox2-ps1,LOC100910973,Ybx1-ps3,Nnat,Gcgr,LOC680254)and eight down-regulated(Rmrp,Terc,Ngrn,Ppp2r2b,Cox6a2,Rpl37a-ps1,LOC360231,Rpph1)—demonstrated fold changes>2 in response to transection SCI.A subset of these RNA-seq results was validated by quantitative real-time PCR.The levels of 821 mRNAs were also significantly altered post-SCI;592 mRNAs were up-regulated and 229 mRNAs were down-regulated by more than 2-fold.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)analyses showed that differentially expressed mRNAs were related to GO biological processes and molecular functions such as injury and inflammation response,wound repair,and apoptosis,and were significantly enriched in 15 KEGG pathways,including cell phagocytosis,tumor necrosis factor alpha pathway,and leukocyte migration.Our results reveal the expression profiles of lncRNAs and mRNAs in the rat spinal cord of a complete transection model,and these differentially expressed lncRNAs and mRNAs represent potential novel targets for SCI treatment.We suggest that lncRNAs may play an important role in the early immuno-inflammatory response after spinal cord injury.This study was approved by the Administration Committee of Experimental Animals,Guangdong Province,China.展开更多
AIM:To assess the expression of nestin and glial fibrillary acidic protein(GFAP)in rat retina after optic nerve transection.METHODS:Rats were randomly divided into normal control group,sham group and operation gro...AIM:To assess the expression of nestin and glial fibrillary acidic protein(GFAP)in rat retina after optic nerve transection.METHODS:Rats were randomly divided into normal control group,sham group and operation group,and used for establishing an animal model of optic nerve transection.Retinal specimen of each group was collected at 3,48h,7and 14d postoperative.Nestin and GFAP expressions on sagittal sections were analyzed by immunohistochemical staining,and protein extraction was analyzed by Western blot.RESULTS:Immunohistochemical analysis showed that nestin positive staining was rarely detected in normal control group and sham group,while sham group showed weak positive staining at 3h postoperative,the reaction gradually increased at 48h postoperative,and reached its maximum at 7d postoperative,and then decreased at 14d postoperative.Compared to the expression of GFAP,there was not statistically significant obvious difference among three groups(P〉0.05).Result of Western blot method was consistent with that of immunohistochemical method.CONCLUSION:The expression of nestin increased in a time dependent fashion in Müller cells of retina following optic nerve transection,which was statistically significant,but there was no obvious difference in GFAP expression.The results indicate that an increase in colloid synthesis in retina following optic nerve transection can improve the retinal neurons’environment.展开更多
An abrupt ice and snow storm disaster which occurred in the spring of 2008 severely destroyed forests over a surprisingly large portion of southern China. A transect crossing Jinggang Mountain-Jitai Basin-Yushan Mount...An abrupt ice and snow storm disaster which occurred in the spring of 2008 severely destroyed forests over a surprisingly large portion of southern China. A transect crossing Jinggang Mountain-Jitai Basin-Yushan Mountain-Wuyi Mountain was selected as the study area. The authors integrated field data collected in two field surveys to analyze the impacts of the disturbance on forests. The following results were obtained. (1) The extent of damage to plantations along the transect decreased in the order of slash pine 〉 masson pine 〉 mixed plantation 〉 Chinese fir. Slash pine is an introduced species from southern America which is characterized by fast growth, low wood quality and rich oleoresin, and showed a damage rate of 61.3% of samples, of which 70.4% cannot recover naturally. Masson pine is the native pioneer species of forests with harder wood, and 52.5% were damaged due to turpentine, of which 60.9% cannot recovery naturally. Chinese fir is a local tree species and samples showed a rate of 46% and a relative rate of 32.5%, lower than the mixed plantation. (2) From west to east along the transect, we can see that evergreen broad-leaved forest of the western transect on Jinggang Mountain showed the lightest damage extent, and a Cryptomeria plantation at an altitude of 700 m was severely destroyed while Chinese fir showed light damage below 700 m and relatively severe damage above 900 m. Masson pine and slash pine in the central transect in Jitai Basin were damaged severely due to turpentine activities, and closed natural secondary deciduous broad-leaved forest was damaged severely due to high ice and snow accumulation on intertwined shrubs. Masson pine aerial-seeding plantations below 400 m along the eastern transect in Xingguo and Ningdu counties were nearly undamaged for small tree sizes, and Chinese fir at 500-900 m altitude showed a lighter damage extent. However, masson pine which was distributed above 400 m and planted in the 1960s, was severely damaged due to turpentine.展开更多
BACKGROUND: The hippocampus regulates the hypothalamic-pituitary-adrenal axis through negative feedback. The hypothalamic paraventricular nucleus receives neuronal input from the hippocampus via the fomix, OBJECTIVE...BACKGROUND: The hippocampus regulates the hypothalamic-pituitary-adrenal axis through negative feedback. The hypothalamic paraventricular nucleus receives neuronal input from the hippocampus via the fomix, OBJECTIVE: To explore whether the negative feedback effect of the hippocampus on the hypothalamic-pituitary-adrenal axis is contributed to the inhibitory effect of mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) in the hippocampus on the paraventricular nucleus via the fornix. DESIGN, TIME AND SETTING: Randomized, controlled, animal experiment. The study was performed at the Department of Histology and Embryology, China Medical University between September 2006 and September 2008. MATERIALS: Rabbit anti-rat anti-MR and rabbit anti-rat anti-GR antibodies were purchased from Santa Cruz Biotechnology, USA. Rabbit anti-rat anti-corticotrophin releasing hormone (CRH) and rabbit anti-rat anti-arginine vasopressin antibodies were purchased from Wuhan Boster. METHODS: A total of 90 male, Wistar rats were randomly divided into model and sham-surgery groups (n = 45). Fornix transection was performed in the model group, while the sham-surgery group underwent surgery, but no fornix transection. MAIN OUTCOME MEASURES: Immunohistochemistry was used to examine MR and GR expression in the hippocampus, as well as CRH and anti-arginine vasopressin in the paraventricular nucleus. Western blot was used to measure alterations in MR, GR, and CRH protein expression following fomix transection. RESULTS: Compared with the sham-surgery group, there were no obvious changes in MR and GR expression in the hippocampus, or CRH and anti-arginine vasopressin expression in the paraventdcular nucleus within 4 days of fornix transection. However, after 7-10 days, significantly decreased MR and GR expression in the hippocampus, and increased CRH and anti-arginine vasopmssin expression in the paraventricular nucleus were observed (P 〈 0.05-0.01). CONCLUSION: Negative feedback from the hippocampus on the hypothalamic-pituitary-adrenal axis might be mediated through the fornix, and the corticosterene actions mediated by hippocampal corticosteroid receptors indirectly modulated the hypothalamic-pituitary-adrenal axis.展开更多
文摘High microsatellite instability(MSI-H)colorectal cancer(CRC),caused by deficient mismatch repair,accounts for about 15%of all CRC cases and is more common in right-sided tumors.While early-stage MSI-H CRC has a relatively good prognosis,advanced cases often respond poorly to standard chemotherapy.Immune checkpoint inhibitors,such as pembrolizumab,have shown strong and lasting effects in MSI-H CRC.Pembrolizumab is now approved as a first-line treatment for metastatic MSI-H CRC due to its superior outcomes compared to traditional chemotherapy.CASE SUMMARY A 44-year-old male with MSI-H transverse colon cancer presented with hematochezia,abdominal pain,and significant weight loss.Imaging revealed a bulky tumor with invasion of adjacent structures and multiple liver lesions.A diverting ileostomy was performed followed by 36 cycles of pembrolizumab.The patient achieved a clinical and radiologic complete response.One month after completing the treatment,the patient underwent laparoscopic right hemicolectomy.A spontaneous transection of the colon at the original tumor site was unexpectedly identified.Final pathology confirmed pathological complete response(ypT0N0)with fibrosis.The patient recovered well after surgery,and follow-up showed no evidence of recurrence.CONCLUSION Immune checkpoint inhibitors may cause delayed structural damage to bowel tissue even after apparent complete tumor regression.
基金supported by National Key R&D Program of China(2021YFA1101200)National Natural Science Foundation of China(82171048+6 种基金81800842)Key R&D Program of Zhejiang Province(2021C03065)Key R&D Program of Wenzhou Eye Hospital(YNZD1201902)Key R&D Program of Wenzhou(ZY2022021)R&D Program of Wenzhou(H20220008)Research Initiation Funds from Wenzhou Eye Hospital(KYQD20221203)China Postdoctoral Science Foundation(2023M742674)。
文摘In adult mammals,optic nerve injury leads to irreversible vision loss due to its extremely limited regenerative capacity.In contrast,adult zebrafish possess a robust capacity for spontaneous visual system regeneration,although the spatiotemporal coordination of recovery across the retina,optic nerve,and brain remains poorly understood.In the present study,the regenerative dynamics following optic nerve transection were systematically characterized in adult zebrafish over a 5 week period using hematoxylin-eosin staining,immunohistochemistry,transmission electron microscopy,single-cell RNA sequencing,and optokinetic response(OKR)behavioral assessments.At 1 week post-injury(1 wpi),retinal ganglion cell depletion was evident but showed significant recovery by 2 wpi.Concurrently,the injured optic nerve displayed a marked increase in diameter and cell number at 2 wpi,including widespread expression of proliferating cell nuclear antigen,consistent with heightened proliferative activity.Single-cell transcriptomic profiling at 2 wpi revealed five principal cell populations:fibroblasts,mural cells,immune cells,mature oligodendrocytes,and myelin-forming oligodendrocytes.By 4-5 wpi,remyelination within the optic nerve and re-establishment of synaptic architecture in the optic tectum were strongly correlated with functional restoration of OKR behavior.These findings provide a comprehensive spatiotemporal framework of visual pathway regeneration in zebrafish,establishing a valuable model for elucidating conserved mechanisms of neural repair with translational potential for human vision restoration.
基金supported by awards from the EPSRC Centre for Doctoral Training in Regenerative Medicine(EP/L014904/1,to JW)an NHS bursary(to RHB)an EPSRC Healthcare Technologies award(EP/T013885/1,to DMC)。
文摘Functional recovery in penetrating neurological injury is hampered by a lack of clinical regenerative therapies.Biomaterial therapies show promise as medical materials for neural repair through immunomodulation,structural support,and delivery of therapeutic biomolecules.However,a lack of facile and pathology-mimetic models for therapeutic testing is a bottleneck in neural tissue engineering research.We have deployed a two-dimensional,high-density multicellular cortical brain sheet to develop a facile model of injury(macrotransection/scratch wound)in vitro.The model encompasses the major neural cell types involved in pathological responses post-injury.Critically,we observed hallmark pathological responses in injury foci including cell scarring,immune cell infiltration,precursor cell migration,and shortrange axonal sprouting.Delivering test magnetic particles to evaluate the potential of the model for biomaterial screening shows a high uptake of introduced magnetic particles by injury-activated immune cells,mimicking in vivo findings.Finally,we proved it is feasible to create reproducible traumatic injuries in the brain sheet(in multielectrode array devices in situ)characterized by focal loss of electrical spiking in injury sites,offering the potential for longer term,electrophysiology plus histology assays.To our knowledge,this is the first in vitro simulation of transecting injury in a two-dimensional multicellular cortical brain cell sheet,that allows for combined histological and electrophysiological readouts of damage/repair.The patho-mimicry and adaptability of this simplified model of brain injury could benefit the testing of biomaterial therapeutics in regenerative neurology,with the option for functional electrophysiological readouts.
文摘目的比较采用毛囊单位钻取术(follicular unit excision,FUE)喇叭口针和锐针钻取毛囊的临床效果。方法回顾性分析自2024年10月至2025年5月,南方医科大学南方医院进行毛发移植49例患者的临床资料。采用FUE喇叭口针钻取毛囊的患者25例,采用FUE锐针钻取毛囊患者24例。通过查询每例患者供区毛囊钻取情况(包括毛囊钻取时间、毛囊钻取总量及毛囊离断率等)、随访期间供区恢复和并发症情况等,综合分析采用FUE喇叭口针和FUE锐针钻取毛囊的临床效果。结果FUE喇叭口针和FUE锐针组患者中,毛囊的平均钻取总量分别为(5380±237)根毛囊和(5540±204)根毛囊,平均钻取时间分别为(89±23)min和(93±28)min,差异均无统计学意义(P>0.05);平均离断率分别为(4.37±0.31)%和(7.02±0.39)%,差异有统计学意义(P<0.05)。FUE喇叭口针组和FUE锐针组患者供区术后恢复时间均为(3±1)d,并发症发生率差异无统计学意义(P>0.05),术后两组间毛发生长情况无明显差异。结论FUE喇叭口针钻取毛囊具有离断率较低的特点,能够减少毛囊损伤,值得临床推广。
基金This paper was supported by the National Natural Sci-ence Foundation of China (Grant No. 40371001) and the Youth Foundation of Beijing Normal University
文摘An improved Carnegie Ames Stanford Approach model (CASA model) was used to estimate the net primary productivity (NPP) of the Northeast China Transect (NECT) every month from 1982 to 2000. The spatial-temporal distribution of NPP along NECT and its response to climatic change were also analyzed. Results showed that the change tendency of NPP spatial distribution in NECT is quite similar to that of precipitation and their spatial correlation coefficient is up to 0.84 (P 〈 0.01). The inter-annual variation of NPP in NECT is mainly affected by the change of the aestival NPP every year, which accounts for 67.6% of the inter-annual increase in NPP and their spatial correlation coefficient is 0.95 (P 〈 0.01). The NPP in NECT is mainly cumulated between May and September, which accounts for 89.8% of the annual NPP. The NPP in summer (June to August) accounts for 65.9% of the annual NPP and is the lowest in winter. Recent climate changes have enhanced plant growth in NECT. The mean NPP increased 14.3% from 1980s to 1990s. The inter-annual linear trend of NPP is 4.6 gC·m^-2·a^-1, and the relative trend is 1.17%, which owns mainly to the increasing temperature.
文摘The 16 tree species on Northeast China Transect (NECT) were analyzed from the change of geographical distribution, frequency and dominance pattern and the spatial correlation at landscape scale in 1986 and 1994. Pinus koraiensis Sieb. et Zucc. and Fraxinus rhynchophylla Hemsl. had spread rapidly towards west and east, respectively. The frontier form of species had close relation with its movement. The patch size of Pinus koraiensis , Populus davidiana Dode., Phellodendron amurense Rupr., Juglans mandshurica Maxim., Fraxinus mandshurica Rupr., Betula dahurica Pall., Picea koraiensis Nakai, Abies nephrolepis Maxim. and Larix olgeusis var. koreana Nakai decreased, however, Quercus mongolica Fisch., Betula costata Trautv., Acer mono Maxim., Tilia spp., Ulmus spp., Betula platyphylla Suk. and Fraxinus rhynchophylla increased. The frequency pattern of Populus davidiana , Betula platyphylla , Fraxinus rhynchophylla and Betula dahurica changed significantly. The dominance pattern of Populus davidiana , Tilia spp., Juglans mandshurica , Betula platyphylla , Betula dahurica and Abies nephrolepis changed significantly. The spatial correlation between Quercus mongolica and Betula dahurica , Betula costata and Picea spp., Betula costata and Abies nephrolepis , Picea spp. and Abies nephrolepis declined, however, the spatial correlation between Larix spp. and Betula platyphylla , Acer mono and Ulmus spp. increased.
文摘Net photosynthesis ( P n ), transpiration ( E ), stomatal conductance ( g s) and water use efficiency (WUE) of more than 218 species belonging to two different reproductive functional types, i.e. clonal (115 species) and non_clonal species (103 species), along the 1 670 km Northeast China Transect (NECT) were analyzed. The results showed that P n and WUE appeared to be lower in the east and west ends of NECT, with peaks in the middle. Transpiration was found to be higher in the west end, where most temperate desert species were distributed. On the same site, most clonal species showed higher P n and related physiological variables than non_clonal species. For different growth forms over NECT, e.g. forest trees, shrubs and grasses, meadow steppe shrubs and grasses, typical steppe shrubs and grasses, the meadow steppe and typical steppe grasses, showed higher values of physiological variables than the forest or the desert species. But for the two reproductive plant functional types (PFTs), clonal species had higher physiological variables, with averages of 22%, 15%, 23% and 14% higher than the non_clonal ones for P n , E, g s, and WUE, respectively. Such differences indicated that clonal species might have advantages over non_clonal species in utilizing environmental resources such as light, CO 2, and especially water.
基金This paper is supported by GEMOC National Key Center, Macquarie University, Australin.
文摘The effective lithospheric elastic thickness of the continent is an important parameter for examination of the large-scale structure and analyses of the mechanism of isostatic compensation within the plate, and a parameter standing for the strength of the lithosphere. The Te values along Quanzhou-Heishui, the southeast section of the Arctic Ocean-Eurasian Continent-Pacific Ocean geoscience transect, are estimated by using the coherence technique developed by Forsyth. Studies of the feature of the coherence between gravity and topography suggest that at short wavelengths (6. 6-100 km) for each data box that is used to estimate Te, the plate is strong enough to support topographic loads and gravity and topography are uncorrelated. At long wavelengths where the plate is deflected by surface and subsurface loads are compensated by the flexure model. Sichuan land-stone with low heat-flow values has high Te values whereas in Ninghua, Datian, land-stone with high heat-flow values has low Te values, which reflects a correlation, low heat-flow values corresponding to high Te values and high heat-flow values corresponding to low Te values. Te values can be divided into two sections: northwest high section and southeast low section. There is roughly a positive correlation between crustal thickness and effective elastic thickness of the lithosphere.
基金The National Basic Research Program of China, No.2005CB422006 National Natural Science Foundation of China, No.40601006
文摘Livelihoods of farmers and nomads in Tibetan Plateau are severely affected by grassland and herbal resources degeneration. How to help them achieve livelihood diversi- fication is a key sustainable development issue. This paper examines livelihood assets, live- lihood diversification level and livelihood strategies of farmers and nomads in 3 regions of eastern transect in Tibetan Plateau. The results show that livelihood diversification is a popular strategy. From high mountain gorge region to mountain plateau region and plateau region, livelihood diversification level is reduced, and livelihood activities and proportion of extended livelihood also decrease. Livelihood assets and livelihood diversification level decrease with the increase of elevation, mainly shown in human assets and natural assets. Livelihood diversification level is highly correlative with livelihood assets, mainly shown in natural assets, human assets and social assets. Livelihood improvement strategies of farmers and nomads are still based on existing livelihood assets, mainly raising livestock and digging herbs, and less farmers and nomads consider off-farm employment or doing business. Nomads in plateau region should learn much from experiences of extended livelihoods of people in high mountain gorge region and mountain plateau region. Therefore, aids of governments should focus on relieving restricted factors of livelihood diversification and help them improve their abilities to build up extended type livelihoods.
基金supported by the National Natural Science Foundation of China,No.81670846(to MMW)and 81470631(to SWY)the Natural Science Foundation of Shaanxi Province of China,No.2016SF-171(to MMW)the National Basic Research Program of China,No.2014CB542202(to SWY)
文摘Our previous studies revealed that etomidate, a non-barbiturate intravenous anesthetic agent, has protective effects on retinal ganglion cells within 7 days after optic nerve transection. Whether this process is related to anti-oxidative stress is not clear. To reveal its mechanism, we established the optic nerve transection injury model by transecting 1 mm behind the left eyeball of adult male Sprague-Dawley rats. The rats received an intraperitoneal injection of etomidate(4 mg/kg) once per day for 7 days. The results showed that etomidate significantly enhanced the number of retinal ganglion cells retrogradely labeled with Fluorogold at 7 days after optic nerve transection. Etomidate also significantly reduced the levels of nitric oxide and malonaldehyde in the retina and increased the level of glutathione at 12 hours after optic nerve transection. Thus, etomidate can protect retinal ganglion cells after optic nerve transection in adult rats by activating an anti-oxidative stress response. The study was approved by the Animal Ethics Committee at Air Force Medical University, China(approval No. 20180305) on March 5, 2018.
基金National Natural Science Foundation of China No.30590381 No.31000211 National Basic Research Program of China No.2010CB833504
文摘From July 2008 to August 2008, 72 leaf samples from 22 species and 81 soil samples in the nine natural forest ecosystems were collected, from north to south along the North-South Transect of Eastern China (NSTEC). Based on these samples, we studied the geographical distribution patterns of vegetable water use efficiency (WUE) and nitrogen use efficiency (NUE), and analyzed their relationship with environmental factors. The vegetable WUE and NUE were calculated through the measurement of foliar δ 13C and C/N of predominant species, respectively. The results showed: (1) vegetable WUE, ranging from 2.13 to 28.67 mg C g-1 H2O, increased linearly from south to north in the representative forest ecosystems along the NSTEC, while vegetable NUE showed an opposite trend, increasing from north to south, ranging from 12.92 to 29.60 g C g-1 N. (2) Vegetable WUE and NUE were dominantly driven by climate and significantly affected by soil nutrient factors. Based on multiple stepwise regression analysis, mean annual temperature, soil phosphorus concentration, and soil nitrogen concentration were responding for 75.5% of the variations of WUE (p0.001). While, mean annual precipitation and soil phosphorus concentration could explain 65.7% of the change in vegetable NUE (p0.001). Moreover, vegetable WUE and NUE would also be seriously influenced by atmospheric nitrogen deposition in nitrogen saturated ecosystems. (3) There was a significant trade-off relationship between vegetable WUE and NUE in the typical forest ecosystems along the NSTEC (p0.001), indicating a balanced strategy for vegetation in resource utilization in natural forest ecosystems along the NSTEC. This study suggests that global change would impact the resource use efficiency of forest ecosystems. However, vegetation could adapt to those changes by increasing the use efficiency of shortage resource while decreasing the relatively ample one. But extreme impacts, such as heavy nitrogen deposition, would break this trade-off mechanism and give a dramatic disturbance to the ecosystem biogeochemical cycle.
基金financially supported by the National Natural Science Foundation of China,No.81371366(to HFW)Characteristic Innovation Project of Colleges and Universities in Guangdong Province of China,No.2018KTSCX075(to HFW)+3 种基金the Key Project of Social Development of Dongguan of China,No.20185071521640(to HFW)College Students’ Science and Technology Innovation Training Project,China,Nos.201810571058,GDMU2018024,GDMU2018056,GDMU2018061(to HFW)College Students’ Innovative Experimental Project in Guangdong Medical University,China,No.ZZDS001(to HFW)College Students’ Science and Technology Innovation Cultivation Project in Guangdong of China,No.pdjh2019b0217(to HFW)
文摘Long non-coding RNAs(lncRNAs)are abundantly expressed in the central nervous system and exert a critical role in gene regulation via multiple biological processes.To uncover the functional significance and molecular mechanisms of lncRNAs in spinal cord injury(SCI),the expression signatures of lncRNAs were profiled using RNA sequencing(RNA-seq)technology in a Sprague-Dawley rat model of the 10th thoracic vertebra complete transection SCI.Results showed that 116 of 14,802 detected lncRNAs were differentially expressed,among which 16—including eight up-regulated(H19,Vof16,Hmox2-ps1,LOC100910973,Ybx1-ps3,Nnat,Gcgr,LOC680254)and eight down-regulated(Rmrp,Terc,Ngrn,Ppp2r2b,Cox6a2,Rpl37a-ps1,LOC360231,Rpph1)—demonstrated fold changes>2 in response to transection SCI.A subset of these RNA-seq results was validated by quantitative real-time PCR.The levels of 821 mRNAs were also significantly altered post-SCI;592 mRNAs were up-regulated and 229 mRNAs were down-regulated by more than 2-fold.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)analyses showed that differentially expressed mRNAs were related to GO biological processes and molecular functions such as injury and inflammation response,wound repair,and apoptosis,and were significantly enriched in 15 KEGG pathways,including cell phagocytosis,tumor necrosis factor alpha pathway,and leukocyte migration.Our results reveal the expression profiles of lncRNAs and mRNAs in the rat spinal cord of a complete transection model,and these differentially expressed lncRNAs and mRNAs represent potential novel targets for SCI treatment.We suggest that lncRNAs may play an important role in the early immuno-inflammatory response after spinal cord injury.This study was approved by the Administration Committee of Experimental Animals,Guangdong Province,China.
基金Supported by Special Scientific Research Program of Shaanxi Provincial Education Department(No.16JK1665)
文摘AIM:To assess the expression of nestin and glial fibrillary acidic protein(GFAP)in rat retina after optic nerve transection.METHODS:Rats were randomly divided into normal control group,sham group and operation group,and used for establishing an animal model of optic nerve transection.Retinal specimen of each group was collected at 3,48h,7and 14d postoperative.Nestin and GFAP expressions on sagittal sections were analyzed by immunohistochemical staining,and protein extraction was analyzed by Western blot.RESULTS:Immunohistochemical analysis showed that nestin positive staining was rarely detected in normal control group and sham group,while sham group showed weak positive staining at 3h postoperative,the reaction gradually increased at 48h postoperative,and reached its maximum at 7d postoperative,and then decreased at 14d postoperative.Compared to the expression of GFAP,there was not statistically significant obvious difference among three groups(P〉0.05).Result of Western blot method was consistent with that of immunohistochemical method.CONCLUSION:The expression of nestin increased in a time dependent fashion in Müller cells of retina following optic nerve transection,which was statistically significant,but there was no obvious difference in GFAP expression.The results indicate that an increase in colloid synthesis in retina following optic nerve transection can improve the retinal neurons’environment.
基金National Natural Science Foundation of China, No.40971281 International Science and Technology Cooperative Program of China, No.2006DFB91920 National Key Project of Scientific and Technical Supporting Programs, No.2006BAC08B00 Acknowledgments We express our thanks to Mr. Fan Zhewen, who is the director of the Remote Sensing Center of Jiangxi province, and Mr. Qiu Zuozhen, who is the director of the Mountain-River-Lake Office of Ji'an City, for their help in the field investigation, and Prof. Wang Hongqing for logistic support. We also gratefully acknowledge the local governments of Jinggangshan City, Taihe County, Xingguo County and Ningdu County, especially Mr. Tang Xiongjie and Ms. He Qingping, for facilitating the field survey and data collection.
文摘An abrupt ice and snow storm disaster which occurred in the spring of 2008 severely destroyed forests over a surprisingly large portion of southern China. A transect crossing Jinggang Mountain-Jitai Basin-Yushan Mountain-Wuyi Mountain was selected as the study area. The authors integrated field data collected in two field surveys to analyze the impacts of the disturbance on forests. The following results were obtained. (1) The extent of damage to plantations along the transect decreased in the order of slash pine 〉 masson pine 〉 mixed plantation 〉 Chinese fir. Slash pine is an introduced species from southern America which is characterized by fast growth, low wood quality and rich oleoresin, and showed a damage rate of 61.3% of samples, of which 70.4% cannot recover naturally. Masson pine is the native pioneer species of forests with harder wood, and 52.5% were damaged due to turpentine, of which 60.9% cannot recovery naturally. Chinese fir is a local tree species and samples showed a rate of 46% and a relative rate of 32.5%, lower than the mixed plantation. (2) From west to east along the transect, we can see that evergreen broad-leaved forest of the western transect on Jinggang Mountain showed the lightest damage extent, and a Cryptomeria plantation at an altitude of 700 m was severely destroyed while Chinese fir showed light damage below 700 m and relatively severe damage above 900 m. Masson pine and slash pine in the central transect in Jitai Basin were damaged severely due to turpentine activities, and closed natural secondary deciduous broad-leaved forest was damaged severely due to high ice and snow accumulation on intertwined shrubs. Masson pine aerial-seeding plantations below 400 m along the eastern transect in Xingguo and Ningdu counties were nearly undamaged for small tree sizes, and Chinese fir at 500-900 m altitude showed a lighter damage extent. However, masson pine which was distributed above 400 m and planted in the 1960s, was severely damaged due to turpentine.
基金the Postdoctoral Science Foundation of China,No. 20060390301the National Natural Science Foundation of China,No.30600341the Ph.D.Program Foundation of Ministry of Education of China,No.20050159011
文摘BACKGROUND: The hippocampus regulates the hypothalamic-pituitary-adrenal axis through negative feedback. The hypothalamic paraventricular nucleus receives neuronal input from the hippocampus via the fomix, OBJECTIVE: To explore whether the negative feedback effect of the hippocampus on the hypothalamic-pituitary-adrenal axis is contributed to the inhibitory effect of mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) in the hippocampus on the paraventricular nucleus via the fornix. DESIGN, TIME AND SETTING: Randomized, controlled, animal experiment. The study was performed at the Department of Histology and Embryology, China Medical University between September 2006 and September 2008. MATERIALS: Rabbit anti-rat anti-MR and rabbit anti-rat anti-GR antibodies were purchased from Santa Cruz Biotechnology, USA. Rabbit anti-rat anti-corticotrophin releasing hormone (CRH) and rabbit anti-rat anti-arginine vasopressin antibodies were purchased from Wuhan Boster. METHODS: A total of 90 male, Wistar rats were randomly divided into model and sham-surgery groups (n = 45). Fornix transection was performed in the model group, while the sham-surgery group underwent surgery, but no fornix transection. MAIN OUTCOME MEASURES: Immunohistochemistry was used to examine MR and GR expression in the hippocampus, as well as CRH and anti-arginine vasopressin in the paraventricular nucleus. Western blot was used to measure alterations in MR, GR, and CRH protein expression following fomix transection. RESULTS: Compared with the sham-surgery group, there were no obvious changes in MR and GR expression in the hippocampus, or CRH and anti-arginine vasopressin expression in the paraventdcular nucleus within 4 days of fornix transection. However, after 7-10 days, significantly decreased MR and GR expression in the hippocampus, and increased CRH and anti-arginine vasopmssin expression in the paraventricular nucleus were observed (P 〈 0.05-0.01). CONCLUSION: Negative feedback from the hippocampus on the hypothalamic-pituitary-adrenal axis might be mediated through the fornix, and the corticosterene actions mediated by hippocampal corticosteroid receptors indirectly modulated the hypothalamic-pituitary-adrenal axis.