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1.

Background

We evaluated whether menstrual cycle phase influences the assessment of tubal patency by hysterosalpingography (HSG) in baboons.

Methods

Retrospective analysis of baseline tubal patency studies and serum estradiol (E2) and progesterone (P4) values obtained from female baboons used as models for development of non‐surgical permanent contraception in women. The main outcome measure was bilateral tubal patency (BTP) in relationship with estradiol level.

Results

Female baboons (n = 110) underwent a single (n = 81), two (n = 26), or three (n = 3) HSG examinations. In 33/142 (23%) HSG examinations, one or both tubes showed functional occlusion (FO). The median E2 in studies with BTP (49 pg/mL) was significantly higher than in those studies with FO (32 pg/mL, P = .005). Among 18 animals with repeat examinations where serum E2 changed from <60 to ≥ 60 pg/mL, 13 results changed from FO to BTP (P = .0001). No sets showed a change from BTP to FO with an increase in estradiol.

Conclusion

In baboons, functional occlusion of the fallopian tube is associated with low estradiol levels, supporting a role for estrogen‐mediated relaxation of the utero‐tubal junction.  相似文献   

2.

Introduction  

The purpose of this study was to compare urate-lowering (UL) efficacy and safety of daily febuxostat and allopurinol in subjects with gout and serum urate (sUA) ≥ 8.0 mg/dL in a six-month trial.  相似文献   

3.

Introduction  

To investigate whether monosodium urate (MSU) crystals induce the production of CCL2 (monocyte chemoattractant protein-1; MCP-1) in human fibroblast-like synoviocytes (FLS) and whether this mechanism would be affected by high-density lipoproteins (HDL).  相似文献   

4.

Background and aims

Although Helicobacter pylori is recognized as an extracellular infection bacterium, it can lead to an increase in the number of CD8+ T cells after infection. At present, the characteristics of H. pylori antigen-specific CD8+ T cells and the epitope response have not been elucidated. This study was focused on putative protective antigen UreB to detect specific CD8+ T-cell responses in vitro and screen for predominant response epitopes.

Methods

The PBMCs collected from H. pylori-infected individuals were stimulated by UreB peptide pools in vitro to identify the immunodominant CD8+ T-cell epitopes. Furthermore, their HLA restriction characteristics were detected accordingly by NGS. Finally, the relationship between immunodominant responses and appearance of gastric symptoms after H. pylori infection was conducted.

Results

UreB-specific CD8+ T-cell responses were detected in H. pylori-infected individuals. Three of UreB dominant epitopes (A-2 (UreB443–451: GVKPNMIIK), B-4 (UreB420–428: SEYVGSVEV), and C-1 (UreB5–13: SRKEYVSMY)) were firstly identified and mainly presented by HLA-A*1101, HLA-B*4001 and HLA-C*0702 alleles, respectively. C-1 responses were mostly occurred in H. pylori-infected subjects without gastric symptoms and may alleviate the degree of gastric inflammation.

Conclusions

The UreB dominant epitope-specific CD8+ T-cell response was closely related to the gastric symptoms after H. pylori infection, and the C-1 (UreB5-13) dominant peptides may be protective epitopes.  相似文献   

5.

Aims

Bioflocculant production potential of an actinobacteria isolated from a freshwater environment was evaluated and the bioflocculant characterized.

Methods and Results

16S rDNA nucleotide sequence and BLAST analysis was used to identify the actinobacteria and fermentation conditions, and nutritional requirements were evaluated for optimal bioflocculant production. Chemical analyses, FTIR, 1H NMR spectrometry and SEM imaging of the purified bioflocculant were carried out. The 16S rDNA nucleotide sequences showed 93% similarities to three Cellulomonas species (strain 794, Cellulomonas flavigena DSM 20109 and Cellulomonas flavigena NCIMB 8073), and the sequences was deposited in GenBank as Cellulomonas sp. Okoh (accession number HQ537132 ). Bioflocculant was optimally produced at an initial pH 7, incubation temperature 30°C, agitation speed of 160 rpm and an inoculum size of 2% (vol/vol) of cell density 1·5 × 10cfu ml?1. Glucose (88·09% flocculating activity; yield: 4·04 ± 0·33 g l?1), (NH4)2NO3 (82·74% flocculating activity; yield: 4·47 ± 0·55 g l?1) and MgCl2 (90·40% flocculating activity; yield: 4·41 g l?1) were the preferred nutritional source. Bioflocculant chemical analyses showed carbohydrate, protein and uronic acids in the proportion of 28·9, 19·3 and 18·7% in CPB and 31·4, 18·7 and 32·1% in PPB, respectively. FTIR and 1H NMR indicated the presence of carboxyl, hydroxyl and amino groups amongst others typical of glycosaminoglycan. SEM imaging revealed horizontal pleats of membranous sheets closely packed.

Conclusion

Cellulomonas sp. produces bioflocculant predominantly composed of glycosaminoglycan polysaccharides with high flocculation activity.

Significance and Impact of the Study

High flocculation activity suggests suitability for industrial applications; hence, it may serve to replace the hazardous flocculant used in water treatment.  相似文献   

6.

Aims

To evaluate the performance of four sampling methods [contact plates, electrostatic wipes (wipe), swabs and a novel roller sampler] for recovery of Staphylococcus aureus from a stainless steel surface.

Methods and Results

Stainless steel test plates were inoculated with Staph. aureus, dried for 24 h and sampled using each of the four methods. Samples were either incubated directly (roller, contact plate) or processed using elution and membrane filtration (swab, wipe). Performance was assessed by calculating the apparent sampling efficiency (ASE), analytical sensitivity (Sn) and percentage of replications with positive growth. The wipe demonstrated the best performance across all inoculating concentrations (ASE48 h = 18%; Sn48 h = 7 CFU per 100 cm2). The swab performed well when corrected for area actually sampled (ASE48 h = 24%; Sn48 h = 76 CFU per 100 cm2). Of the contact‐based methods, the newly developed roller sampler outperformed the contact plate (roller: ASE48 h = 10%; Sn48 h = 17 CFU per 100 cm2; contact plate: ASE48 h = 0·04%; Sn48 h = 1412 CFU per 100 cm2); both contact samplers performed better at higher inoculating concentrations (6E3 CFU per 100 cm2 for the roller and 6E6 CFU per 100 cm2 for the contact plate). Overall, the electrostatic wipe produced the highest number of replications resulting in positive growth (74%24 h, 91%48 h).

Conclusions

This study demonstrates that selection of the sampling method must be carefully considered, given that different methods have varying performance.

Significance and Impact of the Study

This is the first study assessing static wipes for sampling and one that uses a more real‐world‐relevant 24‐h drying time. The results help with infection control, and environmental health professionals choose better sampling methodologies.  相似文献   

7.

Background

Helicobacter pylori eradication therapy was approved in Japan for the first‐line, standard treatment of H. pylori‐positive gastric mucosa‐associated lymphoid tissue (MALT) lymphoma. Although several retrospective studies or small‐scale single‐center studies have been reported, a prospective, large‐scale, nationwide, multicenter study has not been reported from Japan.

Materials and Methods

We conducted a prospective, nationwide, multicenter study to evaluate the clinical efficacy of rabeprazole‐based triple H. pylori eradication therapy for patients with localized gastric MALT lymphoma in practice‐based clinical trial. A total of 108 H. pylori‐positive patients with stage I/II1 gastric MALT lymphoma underwent H. pylori eradication therapy. The primary endpoints were complete remission (CR) rate and the rate of transfer to secondary treatment. The secondary endpoints were CR maintenance duration and overall survival (OS).

Results

CR of lymphoma was achieved in 84 of 97 patients (86.6%), during the period 2.0‐44.7 months (median, 5.3 months) after starting H. pylori eradication treatment. CR was maintained in 77 of 81 patients (95.1%) for 0.4‐53.2 months (median, 33.1 months). Secondary treatments (radiotherapy, rituximab, or gastrectomy) for gastric MALT lymphoma were needed in 10 of the 97 patients (10.31%). During follow‐up, OS rate was 96.9% (94/97) and the causes of 3 deaths were not related to lymphoma.

Conclusions

Rabeprazole‐based H. pylori eradication therapy demonstrated a high CR rate, long CR maintenance, and a good OS for patients with localized gastric MALT lymphoma in this prospective, practice‐based, multicenter study.  相似文献   

8.

Introduction  

The murine air pouch is a bursa-like space that resembles the human synovial membrane. Injection of monosodium urate (MSU) crystals into the pouch elicits an acute inflammatory response similar to human gout. We conducted the present study to identify mRNAs that were highly regulated by MSU crystals in the pouch membrane.  相似文献   

9.

Background  

this study set out to examine the effects of the treatment with 1,25-dihydroxyvitamin D3 (1,25D 3) [150 IU/Kg (3.75 μg/Kg) one a day, for 15 days] to non-diabetic rats and in rats rendered diabetic by a single injection of streptozotocin [65 mg/kg].  相似文献   

10.

Aim

We assessed the generality of the island rule in a database comprising 1593 populations of insular mammals (439 species, including 63 species of fossil mammals), and tested whether observed patterns differed among taxonomic and functional groups.

Location

Islands world‐wide.

Methods

We measured museum specimens (fossil mammals) and reviewed the literature to compile a database of insular animal body size (Si = mean mass of individuals from an insular population divided by that of individuals from an ancestral or mainland population, M). We used linear regressions to investigate the relationship between Si and M, and ANCOVA to compare trends among taxonomic and functional groups.

Results

Si was significantly and negatively related to the mass of the ancestral or mainland population across all mammals and within all orders of extant mammals analysed, and across palaeo‐insular (considered separately) mammals as well. Insular body size was significantly smaller for bats and insectivores than for the other orders studied here, but significantly larger for mammals that utilized aquatic prey than for those restricted to terrestrial prey.

Main conclusions

The island rule appears to be a pervasive pattern, exhibited by mammals from a broad range of orders, functional groups and time periods. There remains, however, much scatter about the general trend; this residual variation may be highly informative as it appears consistent with differences among species, islands and environmental characteristics hypothesized to influence body size evolution in general. The more pronounced gigantism and dwarfism of palaeo‐insular mammals, in particular, is consistent with a hypothesis that emphasizes the importance of ecological interactions (time in isolation from mammalian predators and competitors was 0.1 to > 1.0 Myr for palaeo‐insular mammals, but < 0.01 Myr for extant populations of insular mammals). While ecological displacement may be a major force driving diversification in body size in high‐diversity biotas, ecological release in species‐poor biotas often results in the convergence of insular mammals on the size of intermediate but absent species.  相似文献   

11.

Abstract  

Potentially bioactive N-(aminoalkyl)lactamic amino acids and esters were synthesized in satisfactory to good yields by SNAr reactions of aromatic acids with N-(3-aminopropyl)lactams followed by esterification with tertiary amino alcohols. The addition–elimination SNAr mechanism was confirmed by NMR and MS measurements.  相似文献   

12.

Aims

Investigation of intestinal bacterial groups involved in phytate degradation and the impact of diets with different phytate contents on phytase activity.

Methods and Results

Faecal samples of adults on conventional (n = 8) or vegetarian (n = 8) diets and breastfed infants (n = 6) were used as an inoculum for modified media supplemented with phytate. Populations of Gram‐positive anaerobes (GPA), lactic acid bacteria (LAB), Proteobacteria–Bacteroides (P‐B), coliforms and anaerobes were studied. The PCR‐DGGE analysis revealed a random distribution of DGGE profiles in the dendrograms of GPA, P‐B and coliforms, and a partially diet‐specific distribution in the DGGE dendrograms of LAB and anaerobes. The degradation of phytic acid (PA) was determined with HPLC method in supernatants of the cultures. Regardless of the diet, the Gram‐positive anaerobes and LAB displayed the lowest ability to degrade phytate, whereas the coliforms and P‐B cultures produced higher amounts of intermediate myo‐inositol phosphates. Bacterial populations grown in a nonselective medium were the most effective ones in phytate degradation. It was the vegetarians' microbiota that particularly degraded up to 100% phytate to myo‐inositol phosphate products lower than InsP3.

Conclusions

A diet rich in phytate increases the potential of intestinal microbiota to degrade phytate. The co‐operation of aerobic and anaerobic bacteria is essential for the complete phytate degradation.

Significance and Impact of the Study

This study provides insights on the effect of diet on specific metabolic activity of human intestinal microbiota.  相似文献   

13.

Background  

Entamoeba histolytica is a professional phagocytic cell where the vacuolar ATPase plays a key role. This enzyme is a multisubunit complex that regulates pH in many subcellular compartments, even in those that are not measurably acidic. It participates in a wide variety of cellular processes such as endocytosis, intracellular transport and membrane fusion. The presence of a vacuolar type H+-ATPase in E. histolytica trophozoites has been inferred previously from inhibition assays of its activity, the isolation of the Ehvma1 and Ehvma3 genes, and by proteomic analysis of purified phagosomes.  相似文献   

14.

Background  

Molecular hydrogen is an environmentally-clean fuel and the reversible (bi-directional) hydrogenase of the cyanobacterium Synechocystis sp. PCC 6803 as well as the native Escherichia coli hydrogenase 3 hold great promise for hydrogen generation. These enzymes perform the simple reaction 2H+ + 2e- ↔ H2 (g).  相似文献   

15.

Background  

The aim of this study was to analyze the significance of leucine to proline substitution at position 138(Leu138Pro) on the hydrolysis of penicillin and ampicillin that we identified in the bla SHV gene of clinical Escherichia coli swine isolate.  相似文献   

16.

Aims

To determine whether the carotenoid production improves stress tolerance of lactic acid bacteria, the cloned enterococcal carotenoid biosynthesis genes were expressed in Lactococcus lactis ssp. cremoris MG1363, and the survival rate of carotenoid‐producing engineered MG1363 strain under stress condition was investigated.

Methods and Results

We cloned carotenoid biosynthesis genes from yellow‐pigmented Enterococcus gilvus. The cloned genes consisted of crtN and crtM and its promoter region were inserted into the shuttle vector pRH100, and the resulting plasmid was named pRC. The cloned crtNM was expressed using pRC in noncarotenoid‐producing L. lactis ssp. cremoris MG1363. The expression of crtNM led to the production of C30 carotenoid 4,4′‐diaponeurosporene. After exposure to 32 mmol l?1 H2O2, low pH (1.5, acidified with HCl), 20% bile acid and 12 mg ml?1 lysozyme, the survival rates of the MG1363 strain harbouring pRC were 18.7‐, 6.8‐, 8.8‐ and 4.4‐fold higher, respectively, than those of MG1363 strain harbouring the empty vector pRH100.

Conclusions

The expression of carotenoid biosynthesis genes from Ent. gilvus improves the multistress tolerance of L. lactis.

Significance and Impact of the study

First report of the improvement of multistress tolerance of lactic acid bacteria by the introduction of genes for carotenoid production.  相似文献   

17.

Aim

In this work, phenotypic analyses of a Ensifer meliloti fixN1 mutant under free‐living and symbiotic conditions have been carried out.

Methods and Results

Ensifer meliloti fixN1 mutant showed a defect in growth as well as in TMPD‐dependent oxidase activity when cells were incubated under micro‐oxic conditions. Furthermore, haem c staining analyses of a fixN1 and a fixP1 mutant identified two membrane‐bound c‐type cytochromes of 27 and 32 kDa, present in microaerobically grown cells and in bacteroids, as the FixO and FixP components of the E. meliloti cbb3 oxidase. Under symbiotic conditions, fixN1 mutant showed a clear nitrogen fixation defect in alfalfa plants that were grown in an N‐free nutrient solution during 3 weeks. However, in plants grown for a longer period, fixNOQP1 copy was not indispensable for symbiotic nitrogen fixation.

Conclusions

The copy 1 of the fixNOQP operon is involved in E. meliloti respiration and growth under micro‐oxic conditions as well as in the expression of the FixO and FixP components of the cbb3 oxidase present in free‐living microaerobic cultures and in bacteroids. This copy is important for nitrogen fixation during the early steps of the symbiosis.

Significance and Impact of the Study

It is the first time that a functional analysis of the E. meliloti copy 1 of the fixNOQP operon is performed. In this work, the cytochromes c that constitute the cbb3 oxidase operating in free‐living micro‐oxic cultures and in bacteroids of E. meliloti have been identified.  相似文献   

18.

Background  

The plasma protein α2-antiplasmin (α2AP) is cross-linked to fibrin in blood clots by the transglutaminase factor XIIIa, and in that location retards clot lysis. Competition for this effect could be clinically useful in patients with thrombosis. We hypothesized that fusion of N-terminal portions of α2-antiplasmin to human serum albumin (HSA) and production of the chimeric proteins in Pichia pastoris yeast would produce a stable and effective competitor protein.  相似文献   

19.

Aim

Tapinoma melanocephalum is listed as one of the most important invasive pest species in China. Information regarding the patterns of invasion and effects of geographic isolation on the population genetics of this species is largely lacking.

Location

South China.

Methods

To address this problem, we genotyped 39 colonies (two colonies were collapsed due to genetic similarity) using microsatellite markers and mitochondrial DNA sequencing to compare colony genetic structure of T. melanocephalum on the mainland and islands of South China.

Results

An analysis of the colony genotypes showed that the genetic diversity of the mainland population was slightly higher than that of the island populations but not significantly so. However, the observed heterozygosity on Shangchuan Island (SCD) was significantly lower than that of the other colonies. We also found six haplotypes in 111 mitochondrial DNA COI sequences. The relatedness (r) value between colonies of SCD was 0.410, higher than that of the other populations. The genetic clusters among colonies were not related to geographic locations and exhibited admixture likely due to frequent human‐mediated dispersal associated with trade between the mainland population and the islands. Pairwise FSTs between populations showed differentiation among mainland populations, while SCD displayed high levels of divergence (FST > 0.15) from most mainland populations. There was no significant isolation by distance among colonies. Most populations showed signs of a bottleneck effect.

Main conclusions

Our study suggests that there was no significant difference in the genetic diversity among the islands and the mainland; however, the lower genetic diversity, the higher degree of genetic divergence from other colonies, and the higher relatedness among nestmates made the SCD population stand out from all the others.  相似文献   

20.

Background  

In HIV-1 evolution, a 100–100,000 fold discrepancy between census size and effective population size (N e ) has been noted. Although it is well known that selection can reduce N e , high in vivo mutation and recombination rates complicate attempts to quantify the effects of selection on HIV-1 effective size.  相似文献   

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