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1.
Colorectal cancer (CRC) is one of the leading cancers worldwide. Through genome wide association studies, several single nucleotide polymorphisms scattered in the genome emerged to be influential in the development of sporadic CRC in some populations. However, replicative studies failed to prove a particular SNP-CRC association in populations and ethnic groups. Cyclooxygenase-2 (PTGS2) is a crucial enzyme involved in the metabolism of prostaglandins. The aim of this replicative study is to investigate the possible association between PTGS2?-765G>C polymorphism and sporadic CRC risk in a subset of Iranian population. A total of 110 patients with sporadic CRC, and 120 controls were genotyped for PTGS2?-765G>C polymorphism by using polymerase chain reaction-based restriction fragment length polymorphism. There were no significant differences in the genotype and allele frequencies of PTGS2?-765G>C between two groups except in irregular aspirin or non-steroidal anti-inflammatory drugs (NSAID) consumers. Frequencies of genotypes and alleles were as follows: GG?=?44.2, GC?=?48.3, CC?=?7.5%, in controls and GG?=?34.55, GC?=?60.9, CC?=?4.55% in cases. Regarding the allele frequency, the following values were found: G?=?65, C?=?35% in cases and 68.3, 31.7% in the controls, respectively. In irregular aspirin or NSAID consumers combined GC+CC genotype was found to be a risk genotype (OR?=?1.933, 95% CI: 1.067-3.501, P?=?0.036). Overall, no significant relation was found between this polymorphism and sporadic CRC in Iranians. However, in irregular aspirin or NSAID consumers the combined GC+CC genotype proved to be a risk genotype. 相似文献
2.
The aim of this study was to determine the association between hypertensive nephropathy and gene polymorphisms of vascular
endothelial growth factor (VEGF) in a self-reported Hispanic patient group. A total of 155 Hispanic living kidney donors as
controls and a total of 86 Hispanic kidney transplant patients, whose renal failure was attributed to hypertensive nephropathy
after ruling out diabetes mellitus or other causes, were genotyped for four different single nucleotide polymorphisms of VEGF:
−2578 C>A (rs699947), −1154 G>A (rs1570360), −460 C>T (rs833061), and +936 C>T (rs3025039). The homozygous mutant type (AA)
of VEGF −1154 G>A (rs1570360) was found with significantly higher frequency in the hypertensive nephropathy patients than
in controls. On the other hand, homozygous wild type (GG) was found less frequently in the hypertensive nephropathy patient
group than in the control group. Linkage disequilibrium (LD) analyses revealed a high degree of LD among VEGF −2578 C>A (rs699947),
VEGF −1154 G>A (rs1570360), and VEGF −460 C>T (rs833061). The haplotype analysis revealed that two haplotypes, CGTC and CATC
(in the order of VEGF −2578 C>A (rs699947), −1154 G>A (1570360), −460 C>T (rs833061), and +936 C>T (3025039)), were significantly
associated with hypertensive nephropathy in Hispanic patients. Hence, the −1154 G>A polymorphism (rs1570360) and two haplotypes
(CGTC and CATC) of VEGF appear to be associated with hypertensive nephropathy in Hispanic patients who developed end-stage
renal disease requiring kidney transplant. 相似文献
3.
Inflammatory factors may promote carcinogenesis. Macrophage migration inhibitory factor (MIF), which is derived from T-cell,
known as a member of the transforming growth factor-β (TGF-β) superfamily, plays an important role in the pro- and anti-inflammatory
response to infection and in the etiology of bladder cancer. We hypothesized that MIF-173 locus polymorphism might contribute to genetic susceptibility to bladder cancer. In a hospital-based case–control study
of 325 patients with bladder cancer and 345 cancer-free controls frequency-matched by age, sex, smoking status, and alcohol
use, we genotyped the MIF polymorphism and analyzed immunohistochemical stained operational bladder cancer tissue sections for MIF. We found that individuals
with GC/CC genotype had a significantly decreased risk of bladder cancer (adjusted OR = 0.57, 95% CI, 0.41–0.79) than those
with GG genotype. In the stratification analysis, we found that the decreased risk was more pronounced among older subjects
(adjusted OR = 0.56, 95% CI, 0.39–0.81), men (0.47, 0.33–0.68), smokers (0.54, 0.35–0.85), and ever-drinkers (0.44, 0.27–0.71).
The percentage of positive staining in the cytoplasm and nucleus in the normal and bladder cancer with CC/GC genotype tissues
was higher than that of GG genotype bladder cancer tissue(39.1% vs. 75.0% in strong staining for GG and GC/CC genotypes, respectively,
P = 0.028). In conclusion, MIF -173G>C polymorphism may play a role in the etiology of bladder cancer in southern Chinese population. Large studies are
warranted to validate our findings. 相似文献
4.
Fabio Coppedè Paolo Bosco Valentina Lorenzoni Maria Denaro Guido Anello Ivana Antonucci Concetta Barone Liborio Stuppia Corrado Romano Lucia Migliore 《Molecular biology reports》2014,41(9):5571-5583
We performed a large case–control study and a meta-analysis of the literature to address the role of the methionine synthase reductase (MTRR) c.66A>G polymorphism as a maternal risk factor for the birth of a child with Down Syndrome (DS) among Caucasian women. A total of 253 mothers of a DS child (MDS) and 298 control mothers of Italian origin were included in the case–control study. The meta-analysis of previous and present data involved a total of seven studies performed in Caucasian populations (971 MDS and 1,387 control mothers). Results from the meta-analysis indicated overall a positive significant association between MTRR c.66A>G genotype [OR 1.36 (95 % CI 1.10–1.68), dominant model] and allele frequencies [OR 1.26 (95 % CI 1.04–1.51), allele contrast model] and maternal risk of birth of a child with DS. A sensitivity analysis revealed some interesting differences between Europeans, Caucasians of European descent, and inhabitants of Mediterranean regions, suggesting the possibility of population-specific modifying factors. The case–control study revealed association of the polymorphism with increased folate levels, and a possible interaction with the methionine synthase (MTR) c.2756A>G one, that resulted in a borderline significant maternal risk of birth of a child with DS for the double heterozygous MTR 2756AG/MTRR 66AG genotype [OR 1.79 (95 % CI 1.00–3.18)]. Overall, present data suggest that the MTRR c.66A>G polymorphism represents a risk factor for the birth of a child with DS among white Caucasian women. However, the combined presence of other genetic factors and interactions with geographic and environmental ones, can modify the effect of the single polymorphism alone, leading to population specific effect sizes. 相似文献
5.
TNF-α is a potential proinflammatory cytokine that plays an important role in the pathogenesis of liver cirrhosis. We investigated a possible association between TNF-α -308G>A polymorphism and liver cirrhosis risk by conducting a meta-analysis. Publications addressing the association between TNF-α -308G>A and liver cirrhosis risk were selected from the Pubmed and Embase databases. Data were extracted from the studies by two independent reviewers; odds ratio (OR) with a 95% confidence interval (CI) was calculated from these data. The meta-analysis was performed by Review Manager Version 5.0.24 and STATA Version 9.2. Eleven studies were retrieved, reporting a total of 1796 liver cirrhosis cases and 2113 healthy controls. A meta-analysis of these 11 studies identified no significant association between TNF-α -308G>A polymorphism and liver cirrhosis risk in all comparisons of G vs A allele; GG vs GA + AA; GG + GA vs AA; GG vs AA; GG vs GA (OR = 1.14, 95%CI = 0.85-1.55, P = 0.38; OR = 1.24, 95%CI = 0.87- 1.77, P = 0.24; OR = 0.90, 95%CI = 0.62-1.30, P = 0.57; OR = 1.03, 95%CI = 0.56-1.89, P = 0.92; OR = 1.30, 95%CI = 0.90-1.88, P = 0.17; respectively). In conclusion, we found no association between TNF-α -308G>A polymorphism and liver cirrhosis risk, both in Caucasian and Asian populations. 相似文献
6.
Assila Ben Salem Redha Attaoua Nabil Mtiraoui Sana Belkahla Intissar Ezzidi Mounir Ajina Moncef Souissi Patrick Poucheret Madalina Vintila Florin Grigorescu Touhami Mahjoub 《Molecular biology reports》2014,41(10):6569-6574
Recent studies have suggested that calpain-10 (CAPN10) gene polymorphisms play a role in the susceptibility to polycystic ovary syndrome (PCOS). The aim of the present study was to evaluate the possible association between three single nucleotide polymorphisms (SNPs) in CAPN10 gene: UCSNP-43 (rs3792267), UCSNP-19 (rs3842570), and UCSNP-63 (rs5030952) and PCOS in Tunisian cases and control women. Study subjects included 127 women with PCOS (mean age 29.8 ± 4.7 year) and 150 healthy women (mean age 33.5 ± 5.6 year). CAPN10 genotyping was carried-out by direct PCR and PCR–RFLP. Linkage disequilibrium pattern in the genomic region explored was determined by HAPLOVIEW 4.2 while reconstruction of haplotypes was done using PHASE 2.1. The phylogenetic distribution of haplotypes in the population was determined by ARLEQUIN 2.000. Six haplotypes were observed. None of SNPs associated with PCOS or its components while the haplotype H4 associated with the phenotype PCOS-obese (P < 0.025). Moreover the pair of haplotypes H1/H4 strongly associated with high blood-pressure (OR = 14.4, P < 0.012). This work confirms the association of CAPN10 gene with metabolic components in PCOS and highlights the role of haplotypes as strong and efficient genetic markers. 相似文献
7.
Studies investigating the association between interleukin-10 (IL-10) -1082 promoter polymorphism and gastric cancer risk report conflicting results. Our recent meta-analysis suggests that the IL-10 -1082 promoter polymorphism may be associated with gastric cancer among Asians. The objective of this study was to investigate the association between IL-10 -1082 promoter polymorphism and gastric cancer risk in Chinese Han patients. We extracted the peripheral blood samples in 150 patients with gastric cancer and 150 controls. PCR-RFLP analysis was performed to detect IL-10 -1082 promoter polymorphism in these patients. Patients with gastric cancer had a significantly lower frequency of AA (OR = 0.45, 95% CI = 0.27, 0.76; P = 0.003) than controls. Patients with cardia gastric cancer had a significantly higher frequency of GG (OR = 2.17, 95% CI = 1.08, 4.38; P = 0.03) than those with noncardia gastric cancer. Patients with advanced gastric cancer had a significantly higher frequency of AA (OR = 5.21, 95% CI = 1.71, 15.87; P = 0.004) than those with early gastric cancer. When stratified by the Lauren's classification, histological differentiation of gastric cancer, no statistically significant results were observed. This study suggests that the IL-10 -1082 promoter polymorphism may be associated with gastric cancer in Chinese Han patients, and that difference in genotype distribution may be associated with the location and stage of gastric cancer. 相似文献
8.
Suleeporn Sangrajrang Peter Schmezer Iris Burkholder Paolo Boffetta Paul Brennan Andreas Woelfelschneider 《Biomarkers》2013,18(5):523-532
The X-ray repair cross-complementing group 3 gene (XRCC3) belongs to a family of genes responsible for repairing DNA double-strand breaks caused by normal metabolic processes and exposure to ionizing radiation. Polymorphisms in DNA repair genes may alter an individual's capacity to repair damaged DNA and may lead to genetic instability and contribute to malignant transformation. We examined the role of a polymorphism in the XRCC3 gene (rs861529; codon 241: threonine to methionine change) in determining breast cancer risk in Thai women. The study population consisted of 507 breast cancer cases and 425 healthy women. The polymorphism was analysed by fluorescence-based melting curve analysis. The XRCC3 241Met allele was found to be uncommon in the Thai population (frequency 0.07 among cases and 0.05 among controls). Odds ratios (OR) adjusted for age, body mass index, age at menarche, family history of breast cancer, menopausal status, reproduction parameters, use of contraceptives, tobacco smoking, involuntary tobacco smoking, alcohol drinking, and education were calculated for the entire population as well as for pre- and postmenopausal women. There was a significant association between 241Met carrier status and breast cancer risk (OR 1.58, 95% confidence interval (CI) 1.02–2.44). Among postmenopausal women, a slightly higher OR (1.82, 95% CI 0.95–3.51) was found than among premenopausal women (OR 1.48, 95% CI 0.82–2.69). Our findings suggest that the XRCC3 Thr241Met polymorphism is likely to play a modifying role in the individual susceptibility to breast cancer among Thai women as already shown for women of European ancestry. 相似文献
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11.
Endothelial lipase (EL) is a novel member of the triglyceride (TG) lipase family. A growing body of evidence has indicated that EL gene polymorphism might contribute to the process of cardiovascular diseases. This study was aimed to reveal the potential relationship between EL -384A/C gene polymorphism and acute coronary syndrome (ACS) in a Chinese Han population. The subjects were composed of 320 ACS patients and 315 age- and gender- matched controls. We detected the EL -384A/C genotypes and allele frequencies by using polymerase chain reaction-restriction fragment length polymorphism analysis. There was significant difference in AA genotype and AC+CC genotype between ACS and control groups (P?=?0.014). The A allele frequency was significantly higher in ACS group than in control group (87.8 vs 83.8?%, P?=?0.041). The relationship between the variant and ACS remained significant after adjusting for current smoker, hypertension, diabetes mellitus, total cholesterol and TG (OR?=?0.682, 95?% CI?=?0.472-0.986). The levels of HDL and ApoA-I were significantly higher in AC+CC genotype than in AA genotype (HDL: 1.20?±?0.35 vs 1.11?±?0.29?mmol/L, P?=?0.001; ApoA-I: 1.14?±?0.25 vs 1.08?±?0.21?g/L, P?=?0.009). We found that the EL -384A/C gene polymorphism might be associated with ACS in Chinese Han population, suggesting that the variant might be involved in the pathogenesis of ACS. 相似文献
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13.
Methionine synthase (MTR) is required for the conversion of homocysteine (hcy) to methionine in the one-carbon metabolic pathway. Previous studies investigating a common MTR 2756A>G polymorphism as a maternal risk factor for the birth of a child with Down syndrome (DS) are conflicting and limited by small case–control cohorts, and its contribution to circulating hcy levels is still debated. We performed a large case–control study and a meta-analysis of the literature to further address the role of MTR 2756A>G as a maternal risk factor for the birth of a child with DS. 286 mothers of a DS child (MDS) and 305 control mothers of Italian origin were included in the case–control study. Genotyping was performed by means of PCR/RFLP technique. Data on circulating levels of hcy, folates, and vitamin B12 were available for 189 MDS and 194 control mothers. The meta analysis of previous and present data involved a total of 8 studies (1,171 MDS and 1,402 control mothers). Both the case–control study and the meta-analysis showed no association of MTR 2756A>G with the maternal risk of birth of a child with DS (OR = 1.15; 95 % CI 0.85–1.55, and OR = 1.08; 95 % CI 0.93–1.25, respectively), even after stratification of the overall data available for the meta-analysis into ethnic groups. No association of the studied polymorphism with circulating levels of hcy, folates, and vitamin B12 was observed. Present data do not support a role for MTR 2756A>G as independent maternal risk factor for a DS birth. 相似文献
14.
Genetic polymorphisms in genes that codify inflammatory cytokines have been associated with gastric carcinogenesis. This study evaluated polymorphisms IL-1RN VNTR and TNFB+252A/G in a population from Southeast Brazil with regard to the risk of chronic gastritis and gastric cancer and the presence of an association of gastric lesions with risk factors such as gender, age, smoking, drinking and Helicobacter pylori infection. In this case-control study, polymorphism at IL-1RN VNTR was investigated using the allele-specific polymerase chain reaction method, while the polymerase chain reaction-restriction fragment length polymorphism technique was used to identify the TNFB+252A/G genotype in 675 Brazilian individuals [229 with chronic gastritis (CG), 200 with gastric cancer (GC) and 246 healthy individuals as controls (C)]. Multiple logistic regression analysis (log-additive, dominant, and recessive models) have not showed association of the genotype frequencies for the SNP TNFB + 252A/G with risk of CG or GC. However, as for IL-1RN VNTR it was observed significant differences in all three analysis models, with higher values of OR in recessive model, both in the GC group (OR = 3.04, 95% CI = 1.41-6.56, p < 0.01) and CG (OR = 2.32, 95% CI = 1.10-4.90, p = 0.02) compared to the C group. In addition, the multiple logistic regression showed also an association with risk factors such as male gender, older age and alcohol intake regarded GC group. So, our results indicated that the IL-1RN*2 allele may increase the risk of gastric cancer and precancerous lesions in the Southeast Brazilian population, reinforcing the importance of host genetic factors in the susceptibility to gastric cancer and the participation of cytokines in both the inflammation and the carcinogenic process. 相似文献
15.
Hao Wang Jielin Liu Kuo Liu Ya Liu Zuoguang Wang Yuqing Lou Qiuli Niu Wei Gu Lijuan Wang Mei Li Xiaoling Zhu Shaojun Wen 《Molecular biology reports》2013,40(6):4055-4063
The β1-adrenoceptor (ADRB1) gene Arg389Gly polymorphism has been extensively studied as a candidate gene in essential hypertension (EH), but no consensus has been reached on the relationship between this polymorphism and EH risk. To systematically explore their possible association, a meta-analysis was conducted. All relevant case–control trials in English-language publications before 1 June 2012 were identified by searching the PubMed and Embase databases. Finally, eight articles met our inclusion criteria, including a total of 5,088 patients with EH and 6,515 controls. No evidence of publication bias was found. Fixed-effects model and random-effects model were applied for dichotomous outcomes to combine results from individual studies. Overall, the Gly allelic frequency of Arg389Gly polymorphism was significantly lower in EH subjects than that in controls (Gly versus Arg: P = 0.04, OR = 0.89, 95 % CI [0.80–1.00], P heterogeneity = 0.03, I 2 = 52 %, random-effects model; GlyGly + ArgGly versus ArgArg: P = 0.02, OR = 0.86, 95 % CI [0.76–0.97], P heterogeneity = 0.08 and I 2 = 42 %, random-effect model). Subgroup analysis by ethnicity detected this association only in East Asians. In sensitivity analysis, the study by Bengtsson K was recognized as the main cause of heterogeneity, which was the only one study with the diagnostic standard for EH as systolic blood pressure (SBP) ≥160 mmHg or diastolic blood pressure (DBP) ≥90 mmHg. We concluded that the Gly allele of ADRB1 Arg389Gly polymorphism might confer lower risk for EH, especially in East Asians. 相似文献
16.
A daily dose of vitamin K antagonists (VKAs) may vary and its range depends on various interrelated factors. Low responsiveness to VKA (defined as a failure to achieve a target international normalized ratio [INR]) is associated with polymorphisms of the vitamin K epoxide reductase-oxidase complex gene (VKORC1). A highly prevalent promoter single-nucleotide polymorphism (VKORC1−1639 G>A, rs 17878363) impairsVKORC1 expression and determines the interindividual variability of the target INR. We studied 57 patients receiving oral anticoagulation, including 50 subjects treated with acenocoumarol (mean dose: 5.7±2.3 mg/day) and 7 treated with warfarin (mean dose: 9.6±4.2 mg/day). The indications for the use of oral anticoagulant therapy were as follows: deep-vein thrombosis (N = 23); pulmonary embolism (N = 20); arterial thrombosis (N = 5); stroke (N = 4); atrial fibrillation with transient ischemic attacks (N = 2), and history of multiple thromboembolic events (N = 3). Identification of theVKORC1 genomic variation was performed using DNA sequencing methods. The prevalence of the mutated allele (VKORC1-1639A) was 41%. TheVKORC1-1639G allele carriers required a higher daily dose of acenocoumarol (5.9±1.9 mg) than the noncarriers (4.1±3.3 mg;P < 0.001). All of 5 low responders (who failed to achieve a target INR using standard dose requirements of VKAs) were homozygous for the 1639G allele. Low responders did not differ from good responders with respect to age, gender, and body mass index. Our findings suggest the potential benefits from pharmacogenetic testing, and provide evidence that theVKORC1 −1639 G>A gene polymorphism may explain at least in part the low responsiveness to acenocoumarol. 相似文献
17.
Guillain-Barré syndrome (GBS) is an inflammatory disorder that may implicate proinflammatory cytokines such as tumor necrosis
factor alpha (TNF-alpha) in its pathogenesis. The association between TNF-alpha 308 G/A polymorphism and GBS largely remains
unknown. The aim of this study was to investigate the association between TNF-alpha 308 G/A polymorphism and GBS in Chinese
Han patients. TNF-alpha 308 G/A polymorphism in 150 GBS patients and 150 healthy controls were studied using polymerase chain
reaction–restriction fragment length polymorphism (PCR–RFLP) assay. Patients with GBS had a significantly higher frequency
of TNF-alpha 308AA genotype [odds ratio (OR) = 3.79, 95% confidence interval (CI) = 1.03, 13.94; P = 0.04] than controls. When stratified by the GBS subtype, there was a significantly higher frequency of TNF-alpha 308AA
genotype in patients with AMAN (OR = 6.05, 95% CI = 1.45, 25.31; P = 0.01) and AMSAN (OR = 5.56, 95% CI = 1.18, 26.23; P = 0.03) than controls. There was no significant difference in the distribution of each genotype between patients with AIDP
and the control group. These data indicated that TNF-alpha 308AA genotype was associated with a higher risk of GBS in Chinese
population, especially to AMAN and AMSAN. 相似文献
18.
《Biomarkers》2013,18(3):283-287
Cystathionine β-synthase (CBS) is a key enzyme that plays a critical role in homocysteine metabolism and intracellular redox balance. We have analysed the association of the CBS 844Ins68 polymorphism alone and in combination with methylenetetrahydrofolate reductase (MTHFR C677T) and choline dehydrogenase (CHDH A119C) polymorphisms (the two polymorphisms recently shown to be associated with levels of homocysteine) with homocysteine, cysteine, folate and vitamin B12 in 817 individuals (397 patients with coronary artery disease and 420 controls). The CBS 844Ins68 polymorphism alone or in combination with MTHFR C677T and CHDH A119C polymorphisms was not significantly associated with any of the biochemical variables studied. 相似文献
19.
Esophageal cancer (EC) is a complex multifactorial disorder, where environmental and genetic factors play major role. NADPH:quinone oxidoreductase 1 (NQO1) and NRH:quinone oxidoreductase 2 (NQO2) are phase II cytosolic enzymes that catalyze metabolism of quinones, important in the detoxification of environmental carcinogens. A case-control study was performed to investigated the associations of NQO1 609C>T and NQO2 -3423G>A polymorphisms with susceptibility to EC in a high-risk Kashmiri population of India in 135 EC patients and 195 unrelated healthy controls using PCR-RFLP. We also performed a meta analysis of nine published studies (1,224 cases and 1,740 controls) on NQO1 609C>T and evaluated the association between the NQO1 609C>T polymorphisms and esophageal cancer risk. A significant difference in NQO1 609C>T and NQO2 -3423G>A genotype distribution between EC cases and corresponding controls groups was observed (OR = 2.65; 95 % CI = 1.29-5.42 and OR = 1.88; 95 % CI = 1.02-3.49 respectively). Further, gene-gene interaction showed significantly increased risk for esophageal adenocarcinoma with variant genotypes of NQO1 609C>T and NQO2 -3423G>A polymorphisms and interaction with environmental risk factors revealed pronounced risk of EC with NQO1 609C>T TT genotype in high salted tea users of Kashmir valley (OR = 3.72, 95 % CI = 0.98-14.19). Meta analysis of NQO 609C>T polymorphism also suggested association of the polymorphism with EC in Asians as well as Europeans. In conclusion, NQO1 609C>T and NQO2 -3423G>A genetic variations modulate risk of EC in high-risk Kashmir population. 相似文献
20.
Early warning systems of extinction thresholds have been developed for and tested in microcosm experiments, but have not been applied to populations of wild animals. We used state–space population models and a statistical indicator to detect a transcritical bifurcation extinction threshold in a population of bobwhite quail (Colinus virginianus) located in an agricultural region experiencing habitat deterioration and loss. The extinction threshold was detectible using two independent data sets. We compared predictions from state–space population models to predictions from a statistical indicator and found that predictions were corroborated. Using state–space population models, we estimated that our study population crossed the extinction threshold in 2010 (2002–2036; 95 % confidence intervals [CI]) using the whistle count (WC) data set and in 2008 (1999–2064; 95 % CI) using the Breeding Bird Survey (BBS) data. With the statistical indicator, we estimated that the extinction threshold will be crossed in 2018 (2004–2031; 95 % CI) using the WC data and will be crossed in 2012 (2006–2018; 95 % CI) using the BBS data. We expect extinction in our study population soon after crossing the extinction threshold, but the time to extinction and potential reversibility of the threshold are unknown. Our results suggest that neither small nor decreasing population size will warn of the transcritical bifurcation extinction threshold. We suggest that managers of wildlife populations in regions experiencing land use change should try to predict extinction thresholds and make management decisions to ensure the persistence of the species. 相似文献