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1.
Effect of menstrual cycle phase and hormonal treatments on evaluation of tubal patency in baboons 下载免费PDF全文
Jeffrey T. Jensen Carol Hanna Emily Mishler Jeong Y. Lim Ov D. Slayden 《Journal of medical primatology》2018,47(1):40-45
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.
J.K. Lutz J. Crawford A.E. Hoet J.R. Wilkins III J. Lee 《Journal of applied microbiology》2013,115(1):171-178
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3.
Introduction
We have previously observed that Brown Norway (BN) rats display a relative resistance to experimental Chlamydia-induced arthritis. In the present study, we examine an environmental toxin, mercuric chloride (HgCl2), as a modulator of this innate resistance to arthritis. 相似文献4.
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 × 108 cfu 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5.
Mark V. Lomolino Alexandra A. van der Geer George A. Lyras Maria Rita Palombo Dov F. Sax Roberto Rozzi 《Journal of Biogeography》2013,40(8):1427-1439
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6.
Roberto Cruz-Gervis Arlene A Stecenko Ryszard Dworski Kirk B Lane James E Loyd Richard Pierson Gayle King Kenneth L Brigham 《Respiratory research》2002,3(1):17
Background
Prostanoids are known to participate in the process of fibrogenesis. Because lung fibroblasts produce prostanoids and are believed to play a central role in the pathogenesis of idiopathic pulmonary fibrosis (IPF), we hypothesized that fibroblasts (HF) cultured from the lungs of patients with IPF (HF-IPF) have an altered balance between profibrotic (thromboxane [TX]A2) and antifibrotic (prostacyclin [PGI2]) prostaglandins (PGs) when compared with normal human lung fibroblasts (HF-NL). 相似文献7.
Frank Schreiber Peter Stief Armin Gieseke Ines M Heisterkamp Willy Verstraete Dirk de Beer Paul Stoodley 《BMC biology》2010,8(1):24
Background
Microbial denitrification is not considered important in human-associated microbial communities. Accordingly, metabolic investigations of the microbial biofilm communities of human dental plaque have focused on aerobic respiration and acid fermentation of carbohydrates, even though it is known that the oral habitat is constantly exposed to nitrate (NO3 -) concentrations in the millimolar range and that dental plaque houses bacteria that can reduce this NO3 - to nitrite (NO2 -). 相似文献8.
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9.
Fan-Ching Shen Ih-Jen Su Han-Chieh Wu Yi-Hsuan Hsieh Wei-Jen Yao Kung-Chia Young Tsung-Chuan Chang Hui-Chuan Hsieh Han-Ni Tsai Wenya Huang 《Journal of biomedical science》2009,16(1):84-8
Background
Chronic hepatitis B virus (HBV) infection is an important cause of hepatocellular carcinoma (HCC) worldwide. The pre-S1 and -S2 mutant large HBV surface antigen (LHBS), in which the pre-S1 and -S2 regions of the LHBS gene are partially deleted, are highly associated with HBV-related HCC. 相似文献10.
William P Sheffield Louise J Eltringham-Smith Sharon Gataiance Varsha Bhakta 《BMC biotechnology》2009,9(1):15-11
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11.
Background
The cytotoxicity and the rejoining of DNA double-strand breaks induced by γ-rays, H2O2 and neocarzinostatin, were investigated in normal and PARP-1 knockout mouse 3T3 fibroblasts to determine the role of poly(ADP-ribose) polymerase (PARP-1) in DNA double-strand break repair. 相似文献12.
Nabin Rayamajhi Jeong Chan Joo Seung Bin Cha Subarna Pokherl Min Kyung Shin Young Je Yoo Han Sang Yoo 《BMC microbiology》2011,11(1):29
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13.
James Smith Gerold Diez Anna H Klemm Vitali Schewkunow Wolfgang H Goldmann 《Theoretical biology & medical modelling》2006,3(1):30-7
Background
CapZ is a calcium-insensitive and lipid-dependent actin filament capping protein, the main function of which is to regulate the assembly of the actin cytoskeleton. CapZ is associated with membranes in cells and it is generally assumed that this interaction is mediated by polyphosphoinositides (PPI) particularly PIP2, which has been characterized in vitro. 相似文献14.
Genome-wide identification and analyses of the rice calmodulin and related potential calcium sensor proteins 总被引:2,自引:0,他引:2
Background
A wide range of stimuli evoke rapid and transient increases in [Ca2+]cyt in plant cells which are transmitted by protein sensors that contain EF-hand motifs. Here, a group of Oryza sativa L. genes encoding calmodulin (CaM) and CaM-like (CML) proteins that do not possess functional domains other than the Ca2+-binding EF-hand motifs was analyzed. 相似文献15.
Background
Gelsolin, an actin capping protein of osteoclast podosomes, has a unique function in regulating assembly and disassembly of the podosome actin filament. Previously, we have reported that osteopontin (OPN) binding to integrin αvβ3 increased the levels of gelsolin-associated polyphosphoinositides, podosome assembly/disassembly, and actin filament formation. The present study was undertaken to identify the possible role of polyphosphoinositides and phosphoinositides binding domains (PBDs) of gelsolin in the osteoclast cytoskeletal structural organization and osteoclast function. 相似文献16.
Background
The snake venom group IIA secreted phospholipases A2 (SVPLA2), present in the Viperidae snake family exhibit a wide range of toxic and pharmacological effects. They exert their different functions by catalyzing the hydrolysis of phospholipids (PL) at the membrane/water interface and by highly specific direct binding to: (i) presynaptic membrane-bound or intracellular receptors; (ii) natural PLA2-inhibitors from snake serum; and (iii) coagulation factors present in human blood. 相似文献17.
Genetic diversity and colony structure of Tapinoma melanocephalum on the islands and mainland of South China 下载免费PDF全文
Chunyan Zheng Fan Yang Ling Zeng Edward L. Vargo Yijuan Xu 《Ecology and evolution》2018,8(11):5427-5440
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18.
Piritta Hynninen Jonna M H?m?l?inen Silvia Pastorekova Jaromir Pastorek Abdul Waheed William S Sly Eija Tomas Pertti Kirkinen Seppo Parkkila 《Reproductive biology and endocrinology : RB&E》2004,2(1):73
Background
Carbonic anhydrase (CA) classically catalyses the reversible hydration of dissolved CO2 to form bicarbonate ions and protons. The twelve active CA isozymes are thought to regulate a variety of cellular functions including several processes in the reproductive systems. 相似文献19.
20.
Coulthard LG Costello J Robinson B Shiels IA Taylor SM Woodruff TM 《Arthritis research & therapy》2011,13(2):R42