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1.
Opisthorchis viverrini requires Bithynia snails as the first intermediate host and cyprinid fish as the second intermediate host. Very low natural infection rates have been reported in Bithynia snails, but very high rates have been found in cyprinid fish in the same endemic region. This study investigated the effect of light intensity, the most important stimulus, on the quantity of O. viverrini cercariae shed from naturally infected Bithynia (Digoniostoma) siamensis goniomphalos snails. Snails were evaluated for cercariae output every hour after exposure to various light intensities for a total period of 7 h. The same infected snail was tested under different intensities of light: in the dark, and at 1000, 3000 and 5000 lx. The data showed that under exposure to 1000 and 3000 lx of light, the average percentage and number of cercariae released were higher than that exposed to 5000 lx during the first 2 h of the experiment. In contrast, under higher illumination (5000 lx) a longer time (6 h) was required to stimulate the peak emergence of cercariae. Darkness was not able to induce O. viverrini cercariae emergence. Among the three intensities of light, exposure at 1000 lx induced the highest average number of released cercariae per snail and the highest percentage of cercarial emergence within the first 2 h (125, 54.86%), followed by exposure at 3000 lx (69, 25.58%) and 5000 lx (12, 7.78%). The results suggest that the light intensity of 1000 lx for 2 h would be optimal for O. viverrini cercarial shedding from naturally infected B. (D.) siamensis goniomphalos snails.  相似文献   

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TFF1 is a cysteine-rich protein that forms a characteristic trefoil domain through disulfide bonds, which render it resistant to vigorous conditions and it involves in maintaining the integrity of the gastric mucosa. Decreased expression of TFF1 gene plays a role in the development of gastric cancer. We examined the association between the promoter polymorphisms of the TFF1 gene and the risk of development of gastric cancer, in a case-control study including 199 controls and 141 patients with gastric cancer. Assessment of single nucleotide polymorphisms in the promoter region of the TFF1 gene was performed by sequencing and polymerase chain reaction-based restriction fragment length polymorphism. We found a statistically significant increased risk of gastric cancer associated with − 394 TT genotypes (OR = 8.78, CI = 2.85-27.05, p < 0.001) and CT (OR = 1.64, CI = 1.04-2.60, p = 0.033). This single nucleotide polymorphism occurs naturally in an estrogen response element. According to induction of the TFF1 gene by estrogen, it is possible that the substitution of C to T results in a decreased estrogen receptor binding affinity to the estrogen response element and in turn it decreases the expression of the TFF1 gene that may be involved in development of gastric cancer over a lifetime.  相似文献   

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Human dendritic cells (DCs) play an important role in induction and progression of Crohn's disease (CD). Accumulating evidence suggests that viral infection is required to trigger CD pathogenesis in genetically predisposed individuals. NOD2 and ATG16L1 are among the major CD susceptibility genes implicated in impaired immune response to bacterial infection. In this study, we investigated gene expression and allelic imbalance (AI) of NOD2 and ATG16L1 using common variants in human monocyte-derived DCs. Significant AI was observed in ~ 40% and ~ 70% of NOD2 and ATG16L1 heterozygotes, respectively (p < 0.05). AI of NOD2 was inversely associated with its expression level (p = 0.015). No correlation was detected between gene expression and AI for ATG16L1. When infected with Newcastle Disease Virus (NDV), NOD2 expression in DCs was induced about four-fold (p < 0.001), whereas ATG16L1 expression was not affected (p = 0.88). In addition, NDV infection tended to lower the variance in AI among DC populations for the NOD2 gene (p = 0.05), but not the ATG16L1 gene (p = 0.32). Findings of a simulation study, aimed to verify whether the observed variation in gene expression and AI is a result of sample-to-sample variability or experimental measurement error, suggested that NOD2 AI is likely to result from a deterministic event at a single cell level. Overall, our results present initial evidence that AI of the NOD2 and ATG16L1 genes exists in populations of human DCs. In addition, our findings suggest that viral infection may regulate NOD2 expression.  相似文献   

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The molluscicidal effects of Bayluscide (niclosamide) were investigated on Bithynia siamensis goniomphalos, the first intermediate host of human liver fluke, Opisthorchis viverrini. Lethal concentrations of 50% (LC50) and 95% (LC95) against young and adult males were 0.38 and 0.80, 0.42 and 0.86 ppm, respectively. The LC50 and LC95 against young and adult females were 0.42 and 0.86, 0.46 and 0.97 ppm, respectively. No significant differences in mortality rate between sexes or snail size (p > 0.05) was detected. Bayluscide-related tissue damage in B. siamensis goniomphalos included detachment of cilia of the epithelial layer of the digestive tract and decreased number of calcium cells. In tests of lethal concentrations of Bayluscide on non-target animals, no lethal effect was observed on Filopaludina martensi martensi (Viviparous snail) but high mortality rates were recorded in Puntius gonionotus fingerling, Ricefish (Oryzias mekongensis) and shrimp (Macrobrachium lanchesteri), but lower in guppy fish (Poecilia reticulata) after 24 h exposure. For field trials, sufficient Bayluscide was sprayed in 3 roadside ditches to result in final concentrations of 5, 10 or 20 ppm, with mortality rates on B. siamensis goniomphalos of 10.94, 20.00 and 31.25%, respectively. Non-target snails died in small numbers but no effect was observed in other aquatic vertebrate animals. Field trials of Bayluscide on B. siamensis goniomphalos revealed low mortality rates, suggesting the need for application methods of higher efficacy or that Bayluscide is not suitable for application to operculate snails or snails which are able to escape by burying in mud.  相似文献   

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Objective

Gynecomastia is a benign breast enlargement in males that affects approximately one-third of adolescents. The exact mechanism is not fully understood; however, it has been proposed that estrogen receptors and aromatase enzyme activity may play important roles in the pathogenesis of gynecomastia. While many studies have reported that aromatase enzyme (CYP19) gene polymorphism is associated with gynecomastia, only one study has shown a relationship between estrogen receptor (ER) alpha and beta gene polymorphism and gynecomastia. Thus, the aim of this study was to evaluate the relationships between CYP19 (rs2414096), ER alpha (rs2234693), ER beta (rs4986938), leptin (rs7799039), and leptin receptor (rs1137101) gene polymorphisms and gynecomastia.

Methods

This study included 107 male adolescents with gynecomastia and 97 controls. Total serum testosterone (T) and estradiol (E2) levels were measured, and DNA was extracted from whole blood using the PCR–RFLP technique. The polymorphic distributions of CYP19, ER alpha, ER beta, leptin and leptin receptor genes were compared.

Results

The median E2 level was 12.41 (5.00–65.40) pg/ml in the control group and 16.86 (2.58–78.47) pg/ml in the study group (p < 0.001). The median T level was 2.19 (0.04–7.04) ng/ml in the control group and 1.46 (0.13–12.02) ng/ml in the study group (p = 0.714). There was a significant relationship between gynecomastia and leptin receptor rs1137101 (p = 0.002) and ER beta receptor rs4986938 gene polymorphisms (p = 0.002).

Conclusions

According to our results, increased E2 level and ER beta gene rs4986938 polymorphism might explain why some adolescents have gynecomastia. Leptin receptor gene rs1137101 polymorphism might affect susceptibility to gynecomastia.  相似文献   

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In aquatic environments, endocrine disrupting chemicals (EDCs) that interfere with the reproductive physiology of males form a threat to the reproduction of populations. This is often manifested as decreased sexual performance or sterility among males. We show that exposure to EDCs can directly affect the mating system of a marine fish, the sand goby (Pomatoschistus minutus). We exposed males for 1 to 4 weeks to two different concentrations (5 ng L− 1 and 24 ng L− 1) of 17α-ethinyl estradiol (EE2); a synthetic compound mimicking estrogen and a water control. The sand goby exhibits a polygynous mating system, in which male mating success is typically skewed towards the largest males, resulting in strong sexual selection for increased male size. Our experiment shows that when males have been exposed to EE2, male size has a smaller effect on mating success, resulting in weaker sexual selection on male size as compared to the control. There was an interaction between treatment and exposure time on the expression of vitellogenin and zona radiata protein mRNAs. Males exposed to high EE2 reached much higher expression levels than males exposed to low EE2. Of the somatic markers, the hepatosomatic index was lower in males exposed to high EE2 than in the low EE2 and control males. Our results suggest that exposure to EDCs can have effects on the mating system before physiological changes are observable. These effects can be of profound nature as they interfere with sexual selection, and may in the long run lead to the loss of traits maintained through sexual selection.  相似文献   

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Background

There are nearly 2000 cystic fibrosis transmembrane regulator (CFTR) mutations that cause cystic fibrosis (CF). These mutations are classified into six classes; on the one hand, the first three classes cause severe disease involvement in early childhood, on the other hand, the Class IV, V and VI mutations cause minor severe disease in the same age. Nowadays, with therapeutic advances in CF management and competence of pediatricians, physicians of adults have to deal with two groups of CF patients: (i) adults diagnosed in childhood with severe mutations and (ii) adults who initiated symptoms in adulthood and with Class IV, V and VI mutations. The aim of this study was to analyze adults from a clinical center, treated as CF disease, screening the CFTR genotype and evaluating the clinical characteristics.

Methods

Thirty patients followed as CF disease at the University Hospital were enrolled. After a complete molecular CFTR negative screening and sweat test levels between 40 and 59 mEq/L, five patients were characterized as non-CF disease and were excluded. Molecular screening was performed by CFTR gene sequencing/MLPA or by specific mutation screening. Clinical data was obtained from medical records. The patients were divided into three groups: (1) patients with Class I, II and III mutations in two CFTR alleles; (2) genotype with at least one allele of Class IV, V or VI CFTR mutations and, (3) non-identified CFTR mutation + one patient with one allele with CFTR mutation screened (Class I).

Results

There was an association of CFTR class mutation and sodium/chloride concentration in the sweat test (sodium: p = 0.040; chloride: p = 0.016), onset of digestive symptoms (p = 0.012), lung function parameter (SpO2 — p = 0.016), Bhalla score (p = 0.021), age at diagnosis (p = 0.008) and CF-related diabetes (p = 0.029). There was an association between Pseudomonas aeruginosa chronic colonization (as clinical marker for the lung disease status) and lung impairment (FEV1% — p = 0.027; Bhalla score — p = 0.021), CF-related diabetes (p = 0.040), chloride concentration in the sweat test (p = 0.040) and chronic infection by microorganisms (Staphylococcus aureus — p = 0.039; mucoid P. aeruginosa — p = 0.001). There is no positive association with the status of other clinical markers and the CFTR genotype groups. For clinical association with pancreatic insufficiency (as clinical marker for digestive symptoms), no association was related.

Conclusion

The adults with CF diagnosed by sweat test have specific clinical and genotypic characteristics, being a population that should be studied to cause better future management. Some patients treated as CF disease by clinical symptoms, showed no disease, taking into account the sweat test and complete exon sequencing/MLPA screening.  相似文献   

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We characterized thioredoxin reductase 1 (TrxR1) from Chironomus riparius (CrTrxR1) and studied its expression under oxidative stress. The full-length cDNA is 1820 bp long and contains an open reading frame (ORF) of 1488 bp. The deduced CrTrxR1 protein has 495 amino acids and a calculated molecular mass of 54.41 kDa and an isoelectric point of 6.15. There was a 71 bp 5’ and a 261 bp 3' untranslated region with a polyadenylation signal site (AATAAA). Homologous alignments showed the presence of conserved catalytic domain Cys-Val-Asn-Val-Gly-Cys (CVNVGC), the C-terminal amino acids ‘CCS’ and conserved amino acids required in catalysis. The expression of CrTrxR1 is measured using quantitative real-time PCR after exposure to 50 and 100 mg/L of paraquat (PQ) and 2, 10 and 20 mg/L of cadmium chloride (Cd). CrTrxR1 mRNA was upregulated after PQ exposure at all conditions tested. The highest level of CrTrxR1 expression was observed after exposure to 10 mg/L of Cd for 24 h followed by 20 mg/L for 48 h. Significant downregulation of CrTrxR1 was observed after exposure to 10 and 20 mg/L of Cd for 72 h. This study shows that the CrTrxR1 could be potentially used as a biomarker of oxidative stress inducing environmental contaminants.  相似文献   

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Pyruvate carboxylase (PC) catalyzes the first committed step in gluconeogenesis. Here we investigated the effect of various hormones including cAMP, dexamethasone and insulin on the abundance of PC mRNA in the human hepatocyte cell line, HepG2. Treatment of HepG2 cells with 1 μM of glucagon increased the expression of PC mRNA threefold within 72 h. Treatment with 1 mM 8-Br-cAMP caused the abundance of PC mRNA to increase by 2-3-fold by 48 h, peak at fourfold at 72 h, and remain unchanged to 96 h. This is in contrast to phosphoenolpyruvate carboxykinase (PEPCK) for which expression was decreased after 72 h, suggesting a distinct difference in the control of these two enzymes in the long term. Dexamethasone or insulin alone did not affect the abundance of PC mRNA whereas treatment of HepG2 cells with the combination of 1 mM 8-Br-cAMP and 0.5 μM dexamethasone further increased the abundance of PC mRNA, suggesting the predominant role of 8-Br-cAMP over dexamethasone. Transient transfection of the luciferase reporter construct driven by a 1.95 kbp 5′-flanking sequence of the mouse PC gene and a plasmid encoding the human cAMP-responsive element binding protein increased luciferase reporter activity to 7-fold similar to that observed with a PEPCK promoter-luciferase reporter construct. Deletion of the 5′-flanking region of the PC gene to 781 bp resulted in the complete loss of CREB-mediated induction of reporter gene, suggesting the presence of the cAMP-responsive unit is located between 1.95 kbp and 781 bp upstream of the mouse PC gene. Electrophoretic mobility shifted and chromatin immunoprecipitation assays demonstrated that CREB bind to −1639/−1631 CRE of mouse PC gene in vitro and in vivo, respectively.  相似文献   

14.
Plant excitability, as measured by the appearance and circulation of action potentials (APs) after biotic and abiotic stress treatments, is a far lesser and more versatile phenomenon than in animals. To examine the genetic basis of plant excitability we used different Arabidopsis thaliana accessions. APs were induced by wounding (W) with a subsequent deposition (D) of 5 μL of 1 M KCl onto adult leaves. This treatment elicited transient voltage responses (APs) that were detected by 2 extracellular electrodes placed at a distance from the wounding location over an experimental time of 150 min. The first electrode (e1) was placed at the end of the petiole and the beginning of the leaf, and the second (e2) electrode was placed on the petiole near the center of the rosette. All accessions (Columbia (Col), Wassilewskija (Ws) and Landsberg erecta (Ler)) responded to the W & D treatment. After W & D treatment was performed on 100 plants for each accession, the number of APs ranged from 0 to 37 (median 8, total 940), 0 to 16 (median 5, total 528) and 0 to 18 (median 2, total 296) in Col, Ws and Ler, respectively. Responding plants (>0 APs) showed significantly different behaviors depending on their accessions of origin (i.e., Col 91, Ws 83 and Ler 76%). Some AP characteristics, such as amplitude and speed of propagation from e1 to e2 (1.28 mm s−1), were the same for all accessions, whereas the average duration of APs was similar in Col and Ws, but different in Ler. Self-sustained oscillations were observed more frequently in Col than Ws and least often in Ler, and the mean oscillation frequency was more rapid in Col, followed by Ws, and was slowest in Ler. In general, Col was the most excitable accession, followed by Ws, and Ler was the least excitable; this corresponded well with voltage elicited action potentials. In conclusion, part of Arabidopsis excitability in AP responses is genetically pre-determined.  相似文献   

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Aims

Cervical cancer is the third most frequent cancer in women worldwide, mostly treated with cisplatin-based chemoradiotherapy. Since it is known that folate metabolism might interfere with cisplatin effectiveness, we intended to study the influence of the Gamma Glutamyl Hydrolase -401C > T polymorphism in treatment response in cervical cancer.

Methods

We retrospectively reviewed the clinical data of 167 patients with bulky cervical cancer submitted to cisplatin-based chemoradiotherapy. The genotypes of GGH -401C > T SNP were determined by real-time PCR and statistical analysis was performed by χ2 test and survival analysis.

Results

The genotypes of GGH-401C > T were significantly associated with the response to platinum-based chemoradiotherapy. Treatment response was higher in patients carrying the CC genotype, who presented a significant increased chance of treatment response (survival time in months/genotype: 91 for CC Vs 72 for CT/TT; p = 0.035, log rank test). A Cox regression analysis accordingly showed that the presence of the T allele was significantly linked to a worse treatment response (HR = 3.036; CI 95% 1.032-8.934, p = 0.044).

Conclusions

The results of our study suggested the potential interest of GGH -401C > T as a predictive factor of the outcome of cervical carcinoma treated with cisplatin-based chemoradiotherapy.  相似文献   

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Objective

Recurrent aphthous stomatitis (RAS) is one of the most common oral mucosal diseases, with a multifactorial etiopathogenesis, an interaction between predisposing factors and/or systemic conditions and immunological components in genetically predisposed subjects. Although there is no clear genetic mode of inheritance, there is evidence that inheritance of specific gene polymorphisms may predispose individuals to RAS. The purpose of the present study was to investigate a possible association between the functional interleukin 4 (IL4) VNTR genetic polymorphism and RAS in a sample of Turkish patients.

Methods

The study included 145 unrelated patients with a clinical diagnosis of RAS and 150 unrelated healthy controls. Genomic DNA was isolated and IL4 gene 70 bp VNTR polymorphism determined by using polymerase chain reaction (PCR) with specific primers.

Results

The distribution of genotype and allele frequencies of IL4 gene intron 3 VNTR polymorphism was statistically different between RAS patients and control group (p < 0.0001 and p < 0.0001, respectively) P2P2 genotype and P2 allele were also found to be protective with a lower risk for susceptibility to RAS (p < 0.0001).

Conclusion

The results of this study suggest that intron 3 VNTR polymorphism in the IL4 gene is associated with RAS susceptibility in Turkish population.  相似文献   

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While the lethal toxicity of pyrethroid insecticides to fish is well documented, their sublethal physio-behavioral effects remain poorly characterized. Known pyrethroid-associated changes to insect neuromuscular function may translate into similar effects in fish, thereby altering swimming ability and affecting foraging, predator avoidance, and migration. Three experiments were conducted using critical (Ucrit) and burst (Umax) swimming speeds to assess the sublethal effects of the pyrethroids permethrin and deltamethrin in juvenile rainbow trout (Oncorhynchus mykiss). Fish were exposed to deltamethrin (100, 200, or 300 ng/L) or permethrin (1, 2, or 3 μg/L) in water for 4 d, and assessed for swimming performance. Deltamethrin (200 and 300 ng/L) reduced Ucrit, but not Umax, while both swim performance measurements were unaffected by permethrin. Subsequent experiments used only Ucrit to assess deltamethrin exposure. In a time course experiment, deltamethrin (300 ng/L) reduced Ucrit after 1 and 4 d of exposure, but after 7 d of exposure Ucrit was fully recovered. Finally, deltamethrin (1, 2, or 3 μg/L) reduced Ucrit after 1 h bath exposures similar to recommended protocols for deltamethrin based sea-lice treatment in aquaculture. The real-world implications of the revealed pyrethroid-associated swimming ability reductions in salmon may be important in areas close to aquaculture facilities.  相似文献   

18.

Purpose

Fibromyalgia (FM) syndrome is a form of non-articular rheumatism characterized by long term and widespread musculoskeletal pain, morning stiffness, sleep disturbance, paresthesia, and pressure hyperalgesia at characteristic sites, called soft tissue tender points. The etiology of FM is still obscure. Genetic factors may predispose individuals to FM. Cytokines may play a role in the pathophysiology of FM. The aim of this study was to investigate the interleukin-4 (IL-4) 70 bp VNTR variations in Turkish patients with FM and evaluate if there was an association with clinical features, especially between these polymorphisms.

Methods

The study included 300 patients with FM and 270 healthy controls. Genomic DNA was isolated and genotyped using polymerase chain reaction (PCR) for the IL-4 gene 70 bp VNTR polymorphisms.

Results

There was statistically significant difference between the groups with respect to IL-4 genotype distribution and allele frequencies (p < 0.0001). The homozygous P1P1 genotype and P1 allele were significantly higher in FM patients than in healthy controls (p = 0.04; OR: 3.25, 95% CI: 1–10, p < 0.0001; OR:4.84, 95% CI:3–7.7). There was not any difference between the groups respect to IL-4 genotype distribution and allele frequencies (p > 0.05) and clinical characteristics.

Conclusion

Our findings suggest that there is an association of IL-4 gene 70 bp VNTR polymorphism with susceptibility of a person for development of FM. As a result, further studies are necessary to determine whether IL-4 may be a genetic marker for FM in the Turkish population.  相似文献   

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Little is known about the response of Fasciola spp., inside its snail host to pollutant toxicity. The effect of long-term exposure of Lymnaea natalensis to 0.1 μg/l, 10 μg/l, or 100 μg/l cadmium (Cd) on the infection rates with F. gigantica, percentage of cercariae-shedding snails and cercariae shedding pattern was investigated. The snails were exposed to Cd for 7 days either pre-infection with single Fasciola miracidium or during the late pre-patent period of the infection. The possible interaction between metal exposure and acclimatization temperature was also studied in three ranges; 16-18 °C, 23-25 °C and 30-32 °C. Results clearly showed that host exposure to 100 μg/l Cd significantly affected the pattern of Fasciola development inside its snail host, and that the acclimatization temperature was a key factor affecting the role played by Cd. Pre-infection exposure to Cd caused a significant reduction in the infection rates where the effect was temperature-dependent. Post-infection exposure to Cd significantly increased the percentage of cercariae-shedding snails; the effect was temperature-independent. Interestingly, post-infection exposure significantly altered the differential cercarial output pattern, while no clear impact on the total was found. The alteration in the differential cercarial output was represented as a significantly higher proportion of floating metacercaria as compared to fixed ones and also higher proportion of dead cercariae which may directly reduce the transmission of Fasciola to the final host. The mechanisms of cadmium impact are briefly discussed.  相似文献   

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