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51.
Sousa AF Andrade PZ Pirzgalska RM Galhoz TM Azevedo AM da Silva CL Aires-Barros MR Cabral JM 《Biotechnology letters》2011,33(12):2373-2377
A novel cell separation process based on immunoaffinity aqueous two phase systems is presented to isolate and purify CD34+ stem/progenitor cells directly from the whole umbilical cord blood (UCB). A system, composed of polyethylene glycol and dextran,
was evaluated for the selective recovery of CD34+ cells from UCB. A monoclonal antibody against the CD34 surface antigen was used for the direct partitioning of CD34+ cells in UCB to the PEG-rich phase. The initial population of CD34+ cells (0.2% of the initial sample) was enriched to values up to 42% in a single partitioning step, while the majority of
contaminant cells were partitioned to the dextran-rich phase (1.37 × 10−2 < KP < 2.76 × 10−2). This novel selection method allowed a recovery yield of 95% of CD34+ cells with a purification factor of 245 and is expected to pave a new way to purify hematopoietic stem/progenitor cells for
use in a variety of clinical settings. 相似文献
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53.
Jessica Tauany Andrade Geisa Fantini de Figueiredo Luisa Ferreira Cruz Sarah Eliza de Morais Carla Daiane Ferreira Souza Flávia Carmo Horta Pinto Jaqueline Maria Siqueira Ferreira Marcelo Gonzaga de Freitas Araújo 《Revista iberoamericana de micología》2019,36(4):192-199
BackgroundCandida albicans is the main agent that causes vulvovaginal candidiasis. Resistance among isolates to azole antifungal agents has been reported.AimsDue to the well-known antifungal potential of curcumin, the purpose of this work was to evaluate the in vitro anticandidal activity of curcumin and its effect in the treatment of experimental vulvovaginal candidiasis.MethodsThe anticandidal activity of curcumin was investigated against eight Candida strains by the broth microdilution assay, and its mechanism of action was evaluated by testing the binding to ergosterol. Then, the effect of curcumin in the treatment of vulvovaginal candidiasis was evaluated in an immunosuppressed, estrogen treated rat model.ResultsCurcumin showed minimum inhibitory concentration values of 125–1000 μg/ml, and the best result was observed against Candida glabrata. The compound was shown to be able to bind to the ergosterol present in the membrane, event that may be the mechanism of action. In addition, in the in vivo model of vulvovaginal candidiasis with C. albicans, treatments reduced the vaginal fungal burden in infected rats after seven days of treatment with different doses.ConclusionsCurcumin could be considered a promising effective antifungal agent in the treatment of vulvovaginal candidiasis. 相似文献
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Fecal glucocorticoid metabolites and assay validation: Stress response evaluation in captive brown howler monkeys (Alouatta clamitans) 下载免费PDF全文
56.
Steve Horvath Abu NM Nazmul-Hossain Rodney PE Pollard Frans GM Kroese Arjan Vissink Cees GM Kallenberg Fred KL Spijkervet Hendrika Bootsma Sara A Michie Sven U Gorr Ammon B Peck Chaochao Cai Hui Zhou David TW Wong 《Arthritis research & therapy》2012,14(6):1-13
Bone tissue has an exceptional quality to regenerate to native tissue in response to injury. However, the fracture repair process requires mechanical stability or a viable biological microenvironment or both to ensure successful healing to native tissue. An improved understanding of the molecular and cellular events that occur during bone repair and remodeling has led to the development of biologic agents that can augment the biological microenvironment and enhance bone repair. Orthobiologics, including stem cells, osteoinductive growth factors, osteoconductive matrices, and anabolic agents, are available clinically for accelerating fracture repair and treatment of compromised bone repair situations like delayed unions and nonunions. Preclinical and clinical studies using biologic agents like recombinant bone morphogenetic proteins have demonstrated an efficacy similar or better than that of autologous bone graft in acute fracture healing. A lack of standardized outcome measures for comparison of biologic agents in clinical fracture repair trials, frequent off-label use, and a limited understanding of the biological activity of these agents at the bone repair site have limited their efficacy in clinical applications. 相似文献
57.
Atila Iamarino Fernando Lucas de Melo Carla Torres Braconi Paolo Marinho de Andrade Zanotto 《PloS one》2012,7(4)
Although some studies have shown diversity in HIV integrase (IN) genes, none has focused particularly on the gene evolving in epidemics in the context of recombination. The IN gene in 157 HIV-1 integrase inhibitor-naïve patients from the São Paulo State, Brazil, were sequenced tallying 128 of subtype B (23 of which were found in non-B genomes), 17 of subtype F (8 of which were found in recombinant genomes), 11 integrases were BF recombinants, and 1 from subtype C. Crucially, we found that 4 BF recombinant viruses shared a recurrent recombination breakpoint region between positions 4900 and 4924 (relative to the HXB2) that includes 2 gRNA loops, where the RT may stutter. Since these recombinants had independent phylogenetic origin, we argue that these results suggest a possible recombination hotspot not observed so far in BF CRF in particular, or in any other HIV-1 CRF in general. Additionally, 40% of the drug-naïve and 45% of the drug-treated patients had at least 1 raltegravir (RAL) or elvitegravir (EVG) resistance-associated amino acid change, but no major resistance mutations were found, in line with other studies. Importantly, V151I was the most common minor resistance mutation among B, F, and BF IN genes. Most codon sites of the IN genes had higher rates of synonymous substitutions (dS) indicative of a strong negative selection. Nevertheless, several codon sites mainly in the subtype B were found under positive selection. Consequently, we observed a higher genetic diversity in the B portions of the mosaics, possibly due to the more recent introduction of subtype F on top of an ongoing subtype B epidemics and a fast spread of subtype F alleles among the B population. 相似文献
58.
Jamil M Neto Marina GM Viturino Galina Ananina Flvia F Bajano Sueli M da S Costa Alicia B Roque Gessica FS Borges Raissa Franchi Priscila HH Rim Flvio M Medina Fernando F Costa Mnica B de Melo Jos PC de Vasconcellos 《Experimental biology and medicine (Maywood, N.J.)》2021,246(21):2290
This study aimed to investigate the association among genetic variants of the complement pathway CFB R32Q (rs641153), C3 R102G (rs2230199), and CFH (rs1410996) with age-related macular degeneration (AMD) in a sample of the Brazilian population. In a case-control study, 484 AMD patients were classified according to the clinical age-related maculopathy grading system (CARMS) and compared to 479 unrelated controls. The genetic variants rs1410996 of complement H (CFH), rs641153 of complement factor B (CFB), and rs2230199 of complement 3 (C3) were evaluated through polymerase chain reaction (PCR) and direct sequencing. The associations between single nucleotide polymorphisms (SNPs) and AMD, adjusted by age, were assessed by using logistic regression models. A statistically significant association was observed between AMD risk and rs2230199 variant with an OR of 2.01 (P = 0.0002) for CG individuals compared to CC individuals. Regarding the comparison of advanced AMD versus the control group, the OR was 2.12 (P = 0.0036) for GG versus AA genotypes for rs1410996 variant. Similarly, the OR for rs2230199 polymorphism was 2.3034 (P = 5.47e-05) when comparing CG individuals to CC carriers. In contrast, the rs641153 variant showed a significant protective effect against advanced AMD for GA versus GG genotype (OR = 0.4406; P = 0.0019). When comparing wet AMD versus controls, a significant association was detected for rs1410996 variant (OR = 2.16; P = 0.0039) comparing carriers of the homozygous GG versus AA genotype, as well as in the comparisons of GG (OR = 3.0713; P = 0.0046) and CG genotypes (OR = 2.2249; P = 0.0002) versus CC genotype for rs2230199 variant, respectively. The rs641153 variant granted a significant protective effect against wet AMD for GA versus GG genotypes (OR = 0.4601; P = 0.0044). Our study confirmed the risk association between rs2230199 and rs1410996 variants and AMD, and the protective role against AMD for rs641153 variant. 相似文献
59.
Mating in the scaly cricket Ornebius aperta often includes the transfer of many spermatophores to individual females during extended copulatory interactions. We manipulated male condition in staged matings to determine whether this could explain variation in the number of repeated copulations seen across pairs. Males on a high nutrient diet were in good condition, were more likely to mate repeatedly, and transferred more spermatophores on average than low-diet males (in poor condition). High-diet males were more likely to produce a vibratory signal that increased female receptivity to repeated mating attempts. Courtship and copulatory interactions were always terminated by females, and in every case males had already formed a spermatophore when deserted by females. We conclude that variation in male repeated mating success may be due to female choice rather than an inability or unwillingness of low-diet males to produce spermatophores. 相似文献
60.
Sirlene Souza Rodrigues Sartori Katiane de Oliveira Pinto Coelho Nogueira Alípio dos Santos Rocha Clóvis Andrade Neves 《Acta zoologica》2011,92(2):179-186
Rodrigues Sartori, S. S., Nogueira, K. O. P. C., Rocha, A. S. and Neves, C. A. 2011. Morphology of the stomach of the tropical house gecko Hemidactylus mabouia (Squamata: Gekkonidae). —Acta Zoologica (Stockholm) 92 : 179–186. Hemidactylus mabouia is a common species in Brazil, which facilitates its use in research in several areas and allows display it as a benchmark for studies with reptiles. To study the morphology of the stomach of H. mabouia, we carried out anatomical, histological and histochemical analysis. The stomach of H. mabouia is ‘J’ shaped and can be divided into oral fundic (OF), aboral fundic (AF) and pyloric regions. The surface epithelium is composed of mucosecretory cells (MC) containing neutral mucins. In the lamina propria of the OF region, are large ramified tubulo‐acinar glands, which become smaller, less ramified and more tubular towards the AF region, and are simple tubular and short in the pyloric region. The fundic glands contain differentiated neck and pit. The neck is composed of MC containing neutral mucins and the pit is made of oxyntopeptic cells (OC). The OC of the OF region contained many zymogen granules, while those of the AF region contained few zymogen granules and many mitochondria, which suggests the existence of a gradient of pepsinogen and hydrochloric acid secretion. Pyloric glands consisted of MC containing neutral mucins and both argyrophil and argentaffin endocrine cells. 相似文献