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41.
Total anonychia congenita is a very rare disorder in which all the finger nails and the toenails are absent without significant bone anomalies. This condition is reported to have an autosomal dominant inheritance pattern. There are a variety of syndromes or conditions associated with anonychia congenita. In this study we present a monozygotic twin with isolated anonychia congenita totals. Interestingly there is no family history of anonychia and this condition seems to be caused by a sporadic mutation.  相似文献   
42.
We evaluated the effects of melatonin on acetylsalicylic acid (ASA) induced gastroduodenal and jejunal mucosal injury. We used 40 postpubertal rats divided randomly into five groups of eight animals. The control group consisted of untreated animals. The Mel group was injected intraperitoneally (i.p.) with 5 mg/kg melatonin. The ASA group was injected i.p. with 200 mg/kg ASA. The ASA + Mel group was injected i.p. with 5 mg/kg melatonin 45 min after administering 200 mg/kg ASA i.p. The Mel + ASA group was injected i.p. with 5 mg/kg melatonin 45 min before administering 200 mg/kg ASA i.p. We found no statistically significant differences in mean histopathological scores in the ASA + Mel group compared to the ASA group. ASA caused shortened villi and loss of the apical villus in the duodenum. The histopathological score was increased and villus height was decreased in the ASA group compared to untreated controls. Treatment with melatonin attenuated the histological damage. In the ASA group, occasional areas showed erosion of villi in the jejunum; however, differences in mean histopathological score in ASA group compared to the other groups were not statistically significant. Malondialdehyde (MDA), glutathione (GSH) and superoxide dismutase (SOD) activities were measured in stomach, duodenal and jejunum tissue. We found increased MDA activity in both stomach and duodenal tissues in the ASA group compared to the control group (< 0.05). We found no statistically significant changes in MDA levels in jejunal tissue in the ASA group compared to the control group. We found no change in SOD activity in either stomach or duodenal tissues in the ASA group compared to the control group. We observed decreased SOD activity in jejunal tissue in the ASA group compared to the control group (< 0.05). We detected no change in GSH activity in stomach, duodenal or jejunal tissues in the ASA group compared to the control group. The stomach damage was less in melatonin treated groups, but the lesions were not completely eliminated. The jejunum in the ASA group retained a nearly normal appearance. We found that melatonin exhibited some healing effects on ASA induced duodenal mucosal injury.  相似文献   
43.
44.

Background

Hydroxymethylglutaryl-Coenzyme A Reductase (HMGCR) catalyzes the rate-limiting step of cholesterol biosynthesis. This enzyme is the target of the widely available cholesterol lowering statins. In this population-based case–control study, the frequencies of -911 C>A polymorphism (rs3761740) of the HMGCR gene in patients with coronary heart disease (CHD) and healthy subjects were investigated and the correlations between the different genotypes and hypercholesterolemia with cardiovascular risk factors were analyzed.

Methods

The HMGCR genotypes were determined in 365 patients with CHD and 365 controls by PCR–RFLP assay. Anthropometric measurements were measured in all participants.

Results

There was no significant difference in the genotype frequencies of the HMGCR polymorphism between the male subjects of both patient and control groups, however, the HMGCR-CC genotype was found to be more frequent in female patients with CHD than female controls (p = 0.002). The HMGCR-CC genotype showed higher total-cholesterol (TC) and LDL-cholesterol (LDL-C) levels than the CA + AA genotypes in male CHD patients (p = 0.018). Due to this significant sex interaction, a multivariate analysis was conducted on the patient group. In the multivariate logistic regression analysis, the HMGCR-CC genotype was significantly associated with age < 55 (OR = 2.837, p = 0.001) and TC ≥ 5.18 mmol/L (OR = 1.970, p = 0.027) in male subjects. However, this association was not observed in female patients (p > 0.05). This analysis confirmed that the HMGCR-CC genotype was associated with elevated TC levels in male CHD patients with age < 55 years.

Conclusion

These results suggest that age and sex modify the contribution of the HMGCR-911 polymorphism to fasting serum TC, LDL-C levels and risk of CHD.  相似文献   
45.
We report here a series of 2-thiophene-sulfonamides incorporating 1-substituted aryl-1,2,3-triazolyl moieties, prepared by click chemistry from 5-ethynylthiophene-2-sulfonamide and substituted aryl azides. The new sulfonamides were investigated as inhibitors of the zinc metalloenzyme CA (EC 4.2.1.1), and more specifically against the human (h) cytosolic isoforms hCA I and II and the transmembrane, tumor-associated ones hCA IX and XII: The new compounds were medium–weak hCA I inhibitors (KIs in the range of 224–7544 nM), but were compactly, highly effective, low nanomolar hCA II inhibitors (KIs of 2.2–7.7 nM). The tumor-associated hCA IX was inhibited with KIs ranging between 5.4 and 811 nM, whereas hCA XII with inhibition constants in the range of 3.4–239 nM. The X-ray crystal structure of the adducts of two such compounds bound to hCA II (one incorporating 1-naphthyl, the other one 3-cyanophenyl moieties) evidenced the reasons of the high affinity for hCA II. Highly favorable, predominantly hydrophobic interactions between the sulfonamide scaffold and the hCA II active site were responsible for the binding, in addition to the coordination of the sulfamoyl moiety to the zinc ion. The tails of the two inhibitors adopted very diverse orientations when bound to the active site, with the naphthyltriazolyl moiety orientated towards the hydrophobic half of the active site, and the 3-cyanophenyl one pointing towards the hydrophilic half. These data may be used for the structure-based drug design of even more effective hCA II inhibitors, with potential use as antiglaucoma agents or as diuretics.  相似文献   
46.
Cytokinesis in bacteria is initiated by polymerization of the tubulin homologue FtsZ into a circular structure at midcell, the Z-ring. This structure functions as a scaffold for all other cell division proteins. Several proteins support assembly of the Z-ring, and one such protein, SepF, is required for normal cell division in Gram-positive bacteria and cyanobacteria. Mutation of sepF results in deformed division septa. It is unclear how SepF contributes to the synthesis of normal septa. We have studied SepF by electron microscopy (EM) and found that the protein assembles into very large (~50 nm diameter) rings. These rings were able to bundle FtsZ protofilaments into strikingly long and regular tubular structures reminiscent of eukaryotic microtubules. SepF mutants that disturb interaction with FtsZ or that impair ring formation are no longer able to align FtsZ filaments in vitro, and fail to support normal cell division in vivo. We propose that SepF rings are required for the regular arrangement of FtsZ filaments. Absence of this ordered state could explain the grossly distorted septal morphologies seen in sepF mutants.  相似文献   
47.
48.
Pseudophoxinus firati was described from one spring in the upper Euphrates River drainage in Turkey. Here we record this species from seven additional sites, three in the upper Euphrates drainage, one in the upper Seyhan and three in the upper Ceyhan River drainages. These findings largely expand the distribution area of the species and its habitats are discussed.  相似文献   
49.
The effects of ketotifen, meloxicam, phenyramidol-HCl and gadopentetic acid on the enzyme activity of GR were studied using human erythrocyte glutathione reductase (GR) enzymes in vitro. The enzyme was purified 209-fold from human erythrocytes in a yield of 19% with 0.31?U/mg. The purification procedure involved the preparation of haemolysate, ammonium sulphate precipitation, 2',5'-ADP Sepharose 4B affinity chromatography and Sephadex G-200 gel filtration chromatography. Purified enzyme was used in the in vitro studies. In the in vitro studies, IC(50) values and K(i) constants were 0.012?mM and 0.0008?±?0.00021?mM for ketotifen; 0.029?mM and 0.0061?±?0.00127?mM for meloxicam; 0.99?mM and 0.4340?±?0.0890?mM for phenyramidol-HCl; 138?mM and 28.84?±?4.69?mM for gadopentetic acid, respectively, showing the inhibition effects on the purified enzyme. Phenyramidol-HCl showed competitive inhibition, whereas the others showed non-competitive inhibition.  相似文献   
50.
We reconstructed the matrilineal phylogeny of Asian algae-eating fishes of the genus Capoeta based on complete mitochondrial gene for cytochrome b sequences obtained from 20 species sampled from the majority of the range and 44 species of closely related barbs of the genera Barbus s. str. and Luciobarbus. The results of this study show that Capoeta forms a strongly supported monophyletic subclade nested within the Luciobarbus clade, suggesting that specialized scraping morphology appeared once in the evolutionary history of the genus. We detected three main groups of Capoeta: the Mesopotamian group, which includes three species from the Tigris-Euphrates system and adjacent water bodies, the Anatolian-Iranian group, which has the most diversified structure and encompasses many species distributed throughout Anatolian and Iranian inland waters, and the Aralo-Caspian group, which consists of species distributed in basins of the Caspian and Aral Seas, including many dead-end rivers in Central Asia and Northern Iran. The most probable origination pathway of the genus Capoeta is hypothesized to occur as a result of allopolyploidization. The origin of Capoeta was found around the Langhian-Serravallian boundary according to our molecular clock. The diversification within the genus occurred along Middle Miocene-Late Pliocene periods.  相似文献   
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