Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 5 de 5
Filter
Add more filters










Database
Publication year range
1.
Glob Chang Biol ; 30(1): e17114, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38273577

ABSTRACT

Human activity and climate change affect biodiversity and cause species range shifts, contractions, and expansions. Globally, human activities and climate change have emerged as persistent threats to biodiversity, leading to approximately 68% of the ~522 primate species being threatened with extinction. Here, we used habitat suitability models and integrated data on human population density, gross domestic product (GDP), road construction, the normalized difference vegetation index (NDVI), the location of protected areas (PAs), and climate change to predict potential changes in the distributional range and richness of 26 China's primate species. Our results indicate that both PAs and NDVI have a positive impact on primate distributions. With increasing anthropogenic pressure, species' ranges were restricted to areas of high vegetation cover and in PAs surrounded by buffer zones of 2.7-4.5 km and a core area of PAs at least 0.1-0.5 km from the closest edge of the PA. Areas with a GDP below the Chinese national average of 100,000 yuan were found to be ecologically vulnerable, and this had a negative impact on primate distributions. Changes in temperature and precipitation were also significant contributors to a reduction in the range of primate species. Under the expected influence of climate change over the next 30-50 years, we found that highly suitable habitat for primates will continue to decrease and species will be restricted to smaller and more peripheral parts of their current range. Areas of high primate diversity are expected to lose from 3 to 7 species. We recommend that immediate action be taken, including expanding China's National Park Program, the Ecological Conservation Redline Program, and the Natural Forest Protection Program, along with a stronger national policy promoting alternative/sustainable livelihoods for people in the local communities adjacent to primate ranges, to offset the detrimental effects of anthropogenic activities and climate change on primate survivorship.


Subject(s)
Climate Change , Conservation of Natural Resources , Animals , Humans , Primates , Biodiversity , Ecosystem , Human Activities , China
2.
Nan Fang Yi Ke Da Xue Xue Bao ; 31(9): 1605-7, 2011 Sep.
Article in Chinese | MEDLINE | ID: mdl-21945778

ABSTRACT

OBJECTIVE: To assess the value of fluorescence in situ hybridization (FISH) in the diagnosis of common chromosome number aberration in spontaneously aborted fetuses. METHOD: A total of 100 spontaneously aborted fetuses were analyzed by G-banding and by FISH to test chromosome number aberration mainly for chromosomes 13, 18, 21, X and Y, and the results of FISH test was assessed according to those by G-banding test. RESULTS: FISH results were well consistent with those by G-banding test. FISH test identified trisomy in 32 samples and polyploidy in 7 samples. Two samples with cell culture failure were found to have trisomy 16 by FISH. Discrepancies in the results between the two tests occurred in 3 samples, but the results of FISH were verified by other methods. Kappa test between FISH technology and G-banding showed a good consistency between FISH and karyotyping (P<0.05). CONCLUSION: FISH is an effective and rapid method for detecting chromosome number aberration in spontaneously aborted fetuses, and the combination of FISH and karyotyping provides more reliable diagnostic evidence.


Subject(s)
Aborted Fetus , Chromosome Aberrations , In Situ Hybridization, Fluorescence/methods , Female , Humans , Karyotyping , Pregnancy
3.
J Gastroenterol Hepatol ; 26(8): 1309-17, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21443668

ABSTRACT

BACKGROUND AND AIM: Manometric studies on the human lower esophageal sphincter (LES) have shown radial asymmetry of the high-pressure zone (HPZ). The aim of this study was to compare the functional properties of human LES clasp and sling muscles, and to look at their relationship with the expression of muscarinic receptors and intracellular Ca(2+) concentration. METHODS: Muscle strips of sling and clasp fibers from the LES were obtained from patients undergoing subtotal esophagectomy. Isometric tension responses of the strips to acetylcholine were studied. Western blotting and reverse transcription-polymerase chain reaction (RT-PCR) were used to determine the expression of five subtypes of muscarinic receptors. Intracellular Ca(2+) ([Ca(2+) ]i) was measured using laser scanning confocal microscopy. RESULTS: Acetylcholine caused a concentration-dependent increase in the tension of sling and clasp strips, the sling strip being stronger than clasp (P=0.00). Messenger RNA and protein for the five muscarinic acetylcholine receptor (mAChRs) expressed in the sling and clasp muscles were highest for M2, and then in decreasing levels: M(3)>M(1)>M(4)>M(5) . Acetylcholine caused significant elevation of [Ca(2+) ]i in sling and clasp muscle cells in the presence of extracellular Ca2+ (1.5mmol/L), and Ach-induced [Ca(2+) ]i elevation was 1.6 times greater in sling cells than in clasp cells. CONCLUSION: Variation of intracellular concentrations of Ca(2+) may be the reason for differential responses to acetylcholine for sling versus clasp fibers. However, these differences are not associated with the distribution and the level of expression of the five mAChRs between the two muscle types. Further study should focus on the ligand affinity and signal transduction pathway.


Subject(s)
Acetylcholine/pharmacology , Cholinergic Agonists/pharmacology , Esophageal Sphincter, Lower/drug effects , Muscle Contraction/drug effects , Receptors, Muscarinic/drug effects , Aged , Blotting, Western , Calcium/metabolism , Calcium Channel Blockers/pharmacology , Dose-Response Relationship, Drug , Esophageal Sphincter, Lower/innervation , Esophageal Sphincter, Lower/metabolism , Female , Humans , In Vitro Techniques , Male , Microscopy, Confocal , Middle Aged , Nifedipine/pharmacology , RNA, Messenger/metabolism , Receptors, Muscarinic/genetics , Receptors, Muscarinic/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Time Factors
4.
Nan Fang Yi Ke Da Xue Xue Bao ; 30(1): 11-5, 2010 Jan.
Article in Chinese | MEDLINE | ID: mdl-20117974

ABSTRACT

OBJECTIVE: To investigate the value of real-time fluorescence quantitative PCR in the diagnosis of chromosome anepuploidy. METHODS: ABCC4 gene on chromosome 13, TYMS gene on chromosome 18, DSCR3 gene on chromosome 21, HPRT2 gene on chromosome X, and SRY gene on Y chromosome were used as the target genes, with GAPDH gene on chromosome 12 as the control gene. Using double-standard curve fluorescent relative quantitative PCR method with SYBR Green as the fluorescent dye, the gene expression levels were detected and the results were compared with those of karyotype analysis. RESULTS: The ratio of the target gene on chromosome 13 to the control gene showed a significant difference between the normal karyotype group (0.90 - or + 0.31) and trisome group (1.39 - or + 0.12, P=0.003), and the genes on chromosome 18 (1.07 - or + 0.44 vs 1.66 - or + 0.12, P=0.000) and chromosome 21 (0.84 - or + 0.27 vs 1.73 - or + 0.54, P=0.000) showed similar results. The expression of the genes on the X chromosome showed no significant difference between 45, X group and 46,XY group (0.62 - or + 0.12 vs 0.63 - or + 0.25, P=0.965), nor between 46, XX group and 47,XXY group (1.32 - or + 0.37 vs 1.20 - or + 0.35, P=0.326), while a significant difference was noted between the single copy X (including 45,X and 46,XY) and two copies X (46,XX and 47,XXY) (0.63 - or + 0.23 vs 1.26 - or + 0.36, P=0.000). The expression of the target gene on the Y chromosome was not detected in normal females (46,XX), and a significant difference in the expression was found between normal male group (46,XY) and 47,XYY group (1.57 - or + 0.54 vs 3.08 - or + 0.15, P=0.003). CONCLUSION: SYBR Green I real-time fluorescence quantitative PCR can be used for the purpose of rapid diagnosis of chromosome aneuploidy.


Subject(s)
Aneuploidy , Chromosomes, Human, Pair 21/genetics , Organic Chemicals , Reverse Transcriptase Polymerase Chain Reaction/methods , Trisomy/diagnosis , Benzothiazoles , Chromosome Disorders/diagnosis , Chromosomes, Human, Pair 13/genetics , Chromosomes, Human, Pair 18/genetics , Diamines , Female , Fluorescence , Humans , Male , Quinolines
5.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(1): 64-7, 2009 Jan.
Article in Chinese | MEDLINE | ID: mdl-19218115

ABSTRACT

OBJECTIVE: To investigate the value of fetal chromosomal karyotype analysis in cases of early spontaneous abortion. METHODS: Chorionic villus specimens obtained from 110 cases of early spontaneous abortion were cultured for karyotype analysis. RESULTS: Of the 110 cases, chorionic villus was successfully cultured in 103 cases (93.7%), and abnormal embryo karyotypes were identified in 52 cases (50.5%). Trisomy was the most frequent embryo karyotype abnormalities in these cases, and chromosomal aberration occurred in 29 cases (52.9%) of the first spontaneous abortion and in 23 cases (42.6%) of repeated abortions. Female fetuses accounted for 75.5% (78 cases) in the spontaneously aborted fetuses and for 67.3% (35 cases) in fetuses with chromosomal abnormalities. CONCLUSION: Embryo chromosomal abnormality is the most important reason of early spontaneous abortion, and karyotype analysis of the villus helps identify the causes of abortion and ensure the success of the next pregnancy.


Subject(s)
Abortion, Spontaneous/genetics , Abortion, Spontaneous/pathology , Chorionic Villi/pathology , Karyotyping , Adult , Cells, Cultured , Female , Humans , Pregnancy , Pregnancy Trimester, First , Trisomy/genetics
SELECTION OF CITATIONS
SEARCH DETAIL
...