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91.
A mucoidal strain of Rhodococcus rhodochrous was resistant to 10% (vol/vol) n-hexadecane, while its rough derivatives were sensitive. When the extracellular polysaccharide (EPS) produced by the mucoidal strain was added to cultures of the rough strains, the rough strains gained resistance to n-hexadecane. Thus, EPS confer tolerance to n-hexadecane in members of the genus Rhodococcus.  相似文献   
92.
The amino acid sequence of triculamin is established from the amino acid composition of the peptides, which have been obtained by partial acid hydrolysis. It is a branched peptides, and a possible structure of the branched parts is proposed.  相似文献   
93.
Urate is the final metabolite of purine in humans. Renal urate handling is clinically important because under-reabsorption or underexcretion causes hypouricemia or hyperuricemia, respectively. We have identified a urate-anion exchanger, URAT1, localized at the apical side and a voltage-driven urate efflux transporter, URATv1, expressed at the basolateral side of the renal proximal tubules. URAT1 and URATv1 are vital to renal urate reabsorption because the experimental data have illustrated that functional loss of these transporter proteins affords hypouricemia. While mutations affording enhanced function via these transporter proteins on urate handling is unknown, we have constructed kidney-specific transgenic (Tg) mice for URAT1 or URATv1 to investigate this problem. In our study, each transgene was under the control of the mouse URAT1 promoter so that transgene expression was directed to the kidney. Plasma urate concentrations in URAT1 and URATv1 Tg mice were not significantly different from that in wild-type (WT) mice. Urate excretion in URAT1 Tg mice was similar to that in WT mice, while URATv1 Tg mice excreted more urate compared with WT. Our results suggest that hyperfunctioning URATv1 in the kidney can lead to increased urate reabsorption and may contribute to the development of hyperuricemia.  相似文献   
94.
Clinical and functional characterization of URAT1 variants   总被引:1,自引:0,他引:1  
Idiopathic renal hypouricaemia is an inherited form of hypouricaemia, associated with abnormal renal handling of uric acid. There is excessive urinary wasting of uric acid resulting in hypouricaemia. Patients may be asymptomatic, but the persistent urinary abnormalities may manifest as renal stone disease, and hypouricaemia may manifest as exercise induced acute kidney injury. Here we have identified Macedonian and British patients with hypouricaemia, who presented with a variety of renal symptoms and signs including renal stone disease, hematuria, pyelonephritis and nephrocalcinosis. We have identified heterozygous missense mutations in SLC22A12 encoding the urate transporter protein URAT1 and correlate these genetic findings with functional characterization. Urate handling was determined using uptake experiments in HEK293 cells. This data highlights the importance of the URAT1 renal urate transporter in determining serum urate concentrations and the clinical phenotypes, including nephrolithiasis, that should prompt the clinician to suspect an inherited form of renal hypouricaemia.  相似文献   
95.
It is well known that IVM oocytes show a decreased potential for fertility and development compared with in vivo–matured oocytes. In this study, we added reduced glutathione (GSH) to the fertilization medium during IVF to investigate its effect on the fertility and early embryo development of IVM oocytes. The fertilization rate for IVM oocytes and fresh sperm increased with the addition of GSH (0, 1.0, and 2.0 mM: 51%, 76%, and 70%). Moreover, the addition of GSH to the fertilization medium also improved the developmental potential compared with the control sample (0 mM). In addition, we performed IVF using IVM oocytes and frozen/thawed sperm that had been cryopreserved in a mouse bank. Results indicated a marked increase in the fertilization rate when 1.0 mM GSH was added to the fertilization medium compared with when no GSM was used (0.0 mM GSH: 2% (3/195); 1.0 mM GSH: 33% (156/468)). Furthermore, the fertilization rate improved dramatically via zona drilling using laser equipment (52%: 267/516), whereas normal offspring were obtainsed after transferring embryos created via IVF using IVM oocytes and frozen/thawed sperm. This is the first report in which offspring have been obtained via IVF using IVM oocytes and frozen/thawed sperm.  相似文献   
96.
A method for the determination of allethrin and other pesticides in mosquito coils was developed by the combination of shaking extraction and gas chromatography (GC). Allethrin and other pesticides were adequately extracted by shaking for only half an hour with a mixture of toluene and 99% formic acid (5:1). This shaking extraction method was more effective for shortening the extraction time compared with the Soxhlet extraction method, and accurate determination was achieved without the interference from inert materials in the mosquito coils. The recovery of allethrin in various contents from the coils was 96.6 to 97.1%, with a 1.2 to 1.5% coefficient of variation. Furthermore, the recoveries of other pesticides and synergists from the coils were 94 to 102% by this shaking extraction method.  相似文献   
97.
Rhodococcus erythropolis PR4 is a marine bacterium that can degrade various alkanes including pristane, a C(19) branched alkane. This strain produces a large quantity of extracellular polysaccharides (EPS), which are assumed to play an important role in the hydrocarbon tolerance of R. erythropolis PR4. The strain produced an acidic EPS, mucoidan, together with a fatty acid-containing EPS, PR4 FACEPS. The chemical structure of the mucoidan was determined using (1)H and (13)C NMR spectroscopy and by conducting 2D DQF-COSY, TOCSY, HMQC, HMBC, and NOESY experiments. The mucoidan was shown to consist of a pentasaccharide repeating unit with the following structure: [structure: see text].  相似文献   
98.

Background

Dermatophytes represent a group of keratinophilic fungi capable of invading the superficial layer of the skin, hair, and nails of humans and animals. There is a high prevalence of dermatomycosis in tropical regions, and military personnel are susceptible to this kind of infection due to the type of occupational activities.

Objective

This study was to investigate dermatophytosis in military, in addition to predisposing factors to such infections.

Methods

The direct examination of the 221 samples obtained was conducted by preparing fresh slides, clarified with KOH. The clinical materials were seeded in duplicate in SDA and in Mycosel agar medium. The identification of the etiologic agents was performed according to the Riddell technique.

Results

99/221 (44.8 %) of the dermatophyte infection agents distributed in the three taxonomic genera that cause Tinea were recovered. The Trichophyton genus was the most representative and T. rubrum species 33 (33.3 %), the most prevalent. The other species found were as follows: T. tonsurans 13 (13.1 %), T. verrucosum 11 (11.1 %), T. interdigitale 9 (9.1 %), and T. mentagrophytes 6 (6.1 %). Among the most affected anatomical sites were skin 83 (83.8 %) and nails 17 (17.2 %).

Conclusions

Dermatophyte infections are common disorders in tropical countries. These infections lead to a variety of clinical manifestations. This study reports the incidence of dermatophytosis in the military personnel in the Central-West Region of Brazil. The occupational activities of the military individuals, in addition to the hot and humid climate of the region, can predispose them to infection by these fungal entities.  相似文献   
99.
Genetic engineering of post-polyketide synthase-tailoring genes can be used to generate new macrolide analogs through manipulation of the genes involved in their biosynthesis. Rosamicin, a 16-member macrolide antibiotic produced by Micromonospora rosaria IFO13697, contains a formyl group and an epoxide at C-20 and C-12/13 positions which are formed by the cytochrome P450 enzymes RosC and RosD, respectively. The d-mycinose biosynthesis genes in mycinamicin II biosynthesis gene cluster of Micomonospora guriseorubida A11725 were introduced into the rosC and rosD disruption mutants of M. rosaria IFO13697. The resulting engineered strains, M. rosaria TPMA0054 and TPMA0069, produced mycinosyl rosamicin derivatives, IZIV and IZV, respectively. IZIV was identified as a novel mycinosyl rosamicin derivative, 23-O-mycinosyl-20-deoxo-20-dihydrorosamicin.  相似文献   
100.

Introduction

Real-world evidence of the effectiveness of pharmacological thromboprophylaxis for venous thromboembolism (VTE) is limited. Our objective was to assess the effectiveness and safety of thromboprophylactic regimens in Japanese patients undergoing joint replacement in a real-world setting.

Method

Overall, 1,294 patients (1,073 females and 221 males) who underwent total knee arthroplasty (TKA) and 868 patients (740 females and 128 males) who underwent total hip arthroplasty (THA) in 34 Japanese national hospital organization (NHO) hospitals were enrolled. The primary efficacy outcome was the incidence of deep vein thrombosis (DVT) detected by mandatory bilateral ultrasonography up to post-operative day (POD) 10 and pulmonary embolism (PE) up to POD28. The main safety outcomes were bleeding (major or minor) and death from any cause up to POD28.

Results

Patients undergoing TKA (n = 1,294) received fondaparinux (n = 360), enoxaparin (n = 223), unfractionated heparin (n = 72), anti-platelet agents (n = 45), or no medication (n = 594). Patients undergoing THA (n = 868) received fondaparinux (n = 261), enoxaparin (n = 148), unfractionated heparin (n = 32), anti-platelet agents (n = 44), or no medication (n = 383). The incidence rates of sonographically diagnosed DVTs up to POD10 were 24.3% in patients undergoing TKA and 12.6% in patients undergoing THA, and the incidence rates of major bleeding up to POD28 were 1.2% and 2.3%, respectively. Neither fatal bleeding nor fatal pulmonary embolism occurred. Significant risk factors for postoperative VTE identified by multivariate analysis included gender (female) in both TKA and THA groups and use of a foot pump in the TKA group. Only prophylaxis with fondaparinux reduced the occurrence of VTE significantly in both groups. Propensity score matching analysis (fondaparinux versus enoxaparin) showed that the incidence of DVT was lower (relative risk 0.70, 95% confidence interval (CI) 0.58 to 0.85, P = 0.002 in TKA and relative risk 0.73, 95% CI 0.53 to 0.99, P = 0.134 in THA) but that the incidence of major bleeding was higher in the fondaparinux than in the enoxaparin group (3.4% versus 0.5%, P = 0.062 in TKA and 4.9% versus 0%, P = 0.022 in THA).

Conclusions

These findings indicate that prophylaxis with fondaparinux, not enoxaparin, reduces the risk of DVT but increases bleeding tendency in patients undergoing TKA and THA.

Trial registration

University Hospital Medical Information Network Clinical Trials Registry: UMIN000001366. Registered 11 September 2008.  相似文献   
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