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71.
Partitioning of whey proteins, bovine serum albumin and porcine insulin in aqueous two-phase systems 总被引:1,自引:0,他引:1
Alves JG Chumpitaz LD da Silva LH Franco TT Meirelles AJ 《Journal of chromatography. B, Biomedical sciences and applications》2000,743(1-2):235-239
Partitioning of the proteins from cheese whey, bovine serum albumin and porcine insulin were analysed using aqueous two-phase systems (ATPS) prepared with PEG-phosphate, PEG-citrate and PEG-maltodextrin (MD). Proteins were quantified through one of the following methods: FPLC, Bradford and spectrophotometry at 280 nm. Results showed that whey proteins partitioned unevenly on the phases of the systems used, with alpha-lactoalbumin (alpha-La) concentrated in the upper phase and beta-lactoglobulin (beta-Lg) in the lower. Albumin in PEG-MD systems concentrated in the MD-rich lower phase. Porcine insulin showed great affinity with the PEG-rich phase, its partition coefficient was always over 10 and increases with PEG molecular mass. 相似文献
72.
73.
Development and evaluation of a rapid dipstick assay for serodiagnosis of acute human brucellosis
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Smits HL Basahi MA Díaz R Marrodan T Douglas JT Rocha A Veerman J Zheludkov MM Witte OW de Jong J Gussenhoven GC Goris MG van Der Hoorn MA 《Journal of clinical microbiology》1999,37(12):4179-4182
A dipstick assay for the detection of brucella-specific immunoglobulin M antibodies was evaluated with 707 sera from 247 laboratory-confirmed brucellosis patients and 342 control sera from brucellosis-free individuals. These sera were collected from six different countries. The assay was found to be highly sensitive and specific. In addition, the test is easy to use and does not require specialized training or equipment, and the components are stable without a requirement for refrigeration. All of these factors make the test ideal for developing countries and rural settings. 相似文献
74.
Results of unrelated cord blood transplant in fanconi anemia patients: risk factor analysis for engraftment and survival. 总被引:2,自引:0,他引:2
Eliane Gluckman Vanderson Rocha Irina Ionescu Marc Bierings Richard E Harris John Wagner Joanne Kurtzberg Martin A Champagne Carmem Bonfim Marco Bittencourt Philip Darbyshire Manuél-Nicolas Fernandez Franco Locatelli Ricardo Pasquini 《Biology of blood and marrow transplantation》2007,13(9):1073-1082
We retrospectively analyzed results of unrelated cord blood transplantation (UCBT) in 93 Fanconi anemia (FA) patients. Median age at transplantation was 8.6 years (1-45). The units transplanted were HLA-A, -B, or -DRB1 identical in 12 cases, 1 HLA mismatch in 35 cases, and 2 or 3 HLA differences in 45 cases. The median number of nucleated cells (NC) and CD34+ cells infused of recipient weight was 4.9x10(7)/kg and 1.9x10(5)/kg, respectively. Participating centers selected the preparative regimen of their choice, in 57 patients (61%), it included Fludarabine. Graft-versus-host disease (GVHD) prophylaxis consisted mostly of cyclosporine with prednisone. Cumulative incidence (CI) of neutrophil recovery was 60+/-5% at day +60. In multivariate analysis, Fludarabine containing regimen and NC infused>or=4.9x10(7)/kg were associated with higher probability of recovery. CI of grade II-IV acute and of chronic GVHD (aGVHD, cGVHD) was 32%+/-5% and 16%+/-4%, respectively. Overall survival (OS) was 40%+/-5%. In multivariate analysis, factors associated with favorable outcome were use of Fludarabine in the conditioning regimen, number of NC infused>or=4.9x10(7)/kg, and negative cytomegalovirus (CMV) serology in the recipient. In conclusion, factors easily modifiable such as donor selection and a Fludarabine-containing regimen can considerably improve survival in FA patients given a UCBT. These data are the basis for designing prospective protocols. 相似文献
75.
Nomura M Akama KT Alves SE Korach KS Gustafsson JA Pfaff DW Ogawa S 《Neuroscience》2005,130(2):445-456
We examined the distribution of estrogen receptor (ER)-alpha and ER-beta immunoreactive (ir) cells in the dorsal (DRN) and median/paramedian (MPRN) raphe nuclei in male mice. ER-alpha ir neurons were scattered across the three subdivisions (ventral, dorsal, and lateral) of the DRN and the MPRN. Robust ER-beta ir cells were observed throughout the raphe nuclei, and were particularly abundant in the ventral and dorsal subdivisions of the DRN. Using dual-label immunocytochemistry for ER-alpha or ER-beta with tryptophan hydroxylase (TPH), the rate-limiting enzyme for 5-hydroxytryptamine (5-HT) synthesis, over 90% of ER-beta ir cells exhibited TPH-ir in all DRN subdivisions, whereas only 23% of ER-alpha ir cells contained TPH. Comparisons of ER-alpha knockout (alphaERKO) as well as ER-beta knockout (betaERKO) mice with their respective wild-type (WT) littermates revealed that gene disruption of either ER-alpha or ER-beta did not affect the other ER subtype expression in the raphe nuclei. In situ hybridization histochemistry revealed that there was a small but statistically significant decrease in TPH mRNA expression in the ventral DRN subdivision in betaERKO mice compared with betaWT mice, whereas TPH mRNA levels were not affected in alphaERKO mice. These findings support a hypothesis that ER-beta activation may contribute to the estrogenic regulation of neuroendocrine and behavioral functions, in part, by acting directly on 5-HT neurons in the raphe nuclei in male mice. 相似文献
76.
A satellite DNA has been cloned from the neotropical primateCallithrix argentata and designated CarB. The presence of the satellite was assayed in New and Old World primates by blot hybridization: CarB is highly amplified in the genomes of all three species belonging to theC. argentata species group (C. argentata, C. emiliae, C. humeralifer), but is either absent, or present in only minor amounts, in other primates, including the closely related species,C. jacchus. A completely sequenced CarB monomeric unit was 1528 bp in length and mapped to the telomeric C-band-positive regions of manyC. argentata species group chromosomes. Sequence data from eight CarB clones indicated an average difference of 3.5% when base substitutions alone were counted. The hybridization and sequence data suggest that this satellite underwent a period of amplification and dispersal in the genome of a recent ancestor of theC. argentata species group. 相似文献
77.
Rocha V Wagner JE Sobocinski KA Klein JP Zhang MJ Horowitz MM Gluckman E 《The New England journal of medicine》2000,342(25):1846-1854
BACKGROUND: Umbilical-cord blood as an alternative to bone marrow for hematopoietic stem-cell transplantation may lower the risk of graft-versus-host disease (GVHD). METHODS: We studied the records of 113 recipients of cord blood from HLA-identical siblings from the period from 1990 through 1997 and compared them with the records of 2052 recipients of bone marrow from HLA-identical siblings during the same period. The study population consisted of children 15 years of age or younger. We compared the rates of GVHD, hematopoietic recovery, and survival using Cox proportional-hazards regression to adjust for potentially confounding factors. RESULTS: Recipients of cord blood were younger than recipients of bone marrow (median age, 5 years vs. 8 years; P<0.001), weighed less (median weight, 17 kg vs. 26 kg; P<0.001), and were less likely to have received methotrexate for prophylaxis against GVHD (28 percent vs. 65 percent, P<0.001). Multivariate analysis demonstrated a lower risk of acute GVHD (relative risk, 0.41; P=0.001) and chronic GVHD (relative risk, 0.35; P=0.02) among recipients of cord-blood transplants. As compared with recovery after bone marrow transplantation, the likelihood of recovery of the neutrophil count and the platelet count was significantly lower in the first month after cord-blood transplantation (relative risk, 0.40 [P<0.001], and relative risk, 0.20 [P<0.001]), respectively. Mortality was similar in the two groups (relative risk of death in the recipients of cord blood, 1.15; P=0.43). CONCLUSIONS: Recipients of cord-blood transplants from HLA-identical siblings have a lower incidence of acute and chronic GVHD than recipients of bone marrow transplants from HLA-identical siblings. 相似文献
78.
Barreto DF Takiya CM Paes MV Farias-Filho J Pinhão AT Alves AM Costa SM Barth OM 《Journal of submicroscopic cytology and pathology》2004,36(2):121-130
The difficulty in studying dengue virus (DENV) infection in humans and in developing a virus vaccine is the absence of a suitable animal model which develops the full spectra of the Dengue haemorrhagic fever (DHF) and Dengue shock syndrome (DSS). Despite the fact that viruses have been found in various animal tissues, we isolated DENV from tissues of adult BALB/c mice, inoculated with DENV serotype 2 (DENV-2) obtained from human serum. Viruses were ultrastructurally identified and immunolocalized by immunofluorescence techniques in C6/36 mosquito cell cultures, inoculated with tissues (liver, lung, kidney and cerebellum) macerate supernatant from mice, 48 h post-infection (p.i.). These organs, collected at the same stage of infection, were examined histologically. The histopathological analysis revealed focal alterations in all tissues examined. Liver contained focal ballooned hepatocytes, but without modifying the average diameter of the majority of hepatocytes. Sinusoidal lumen was significantly diminished at this stage but portal and centrolobular veins became congested. Lungs exhibited hemorrhagic foci in the alveolar space, vascular congestion and focal alveolitis. Cerebellar tissue showed rare foci of neuronal compactation (Purkinje cells) and perivascular oedema. In kidneys it was observed an increase in glomerular volume with augmented endocapillary and mesangial cellularity, with reactivity to anti-IgM in all glomeruli of infected mice. In conclusion, DENV-2 was found in all tissues examined early in the evolution of infection. Presence of viruses in tissues has mainly led to hemodynamic alterations with generalized vascular congestion and increased permeability, and mast cell recruitment in lungs. The latter could participate in the vascular modifications in tissues. 相似文献
79.
Changes in Serum Immunoglobulin G Levels as a Marker for Cryptosporidium sp. Infection in Peruvian Children
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80.
Pedro Guimarães de Azevedo Luana Reis Miranda Eduardo Souza Nicolau Rayane Benfica Alves Maria Aparecida Camargos Bicalho Patrícia Pereira Couto Adauto Versiani Ramos Renan Pedra de Souza Rafael Longhi Eitan Friedman Luiz De Marco Luciana Bastos-Rodrigues 《Obesity research & clinical practice》2021,15(4):334-338
BackgroundObesity has reached epidemic proportions worldwide, affecting life quality and span. Susceptibility to obesity is partly mediated by genetic differences. Indeed, several genes from the clock gene family have already been shown to be intimately associated with obesity in diverse ethnic groups. In the present study, an association between BMI and the rs707467, rs228697 and rs228729 PER3 (Period Circadian Clock 3) polymorphisms in subjects with class II (BMI ≥ 35.0–39.9 kg/m2) and class III obesity (>40 kg/m2, extreme obesity) were carried out using TaqMan real-time PCR. Overall, 259 Brazilian adults were genotyped, of whom 122 had class II or III obesity (BMI ≥ 35.0 kg/m2) and 137 were controls having normal weight (BMI > 18.5 and <24.9 kg/m2).ResultsPER3 tag SNP (rs228729) shows a significant association with extreme obesity (1000 permutation p = 0.03 and p = 0.04), for genotype and allele frequency respectively) and a haplotype among the three assessed SNPs (alleles G/T/A, rs228697, rs228729, and rs707467, respectively, 1000 permutation p = 0.03) was significantly more prevalent in the group with obesity.ConclusionThis exploratory association study suggests that PER3 rs228729 may be associated with extreme obesity in Brazilian adults, however, replication is needed. 相似文献