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81.
Bilateral abscessed orchiepididymitis associated with sepsis caused by Veillonella parvula and Clostridium perfringens: case report and review of the literature. 下载免费PDF全文
P M Arrosagaray C Salas M Morales M Correas J M Barros M L Cordon 《Journal of clinical microbiology》1987,25(8):1579-1580
Veillonella species is a gram-negative coccus which is part of the anaerobic normal flora in the oral cavity, small intestine, upper respiratory tract, vagina, and urinary tract. The role that this organism plays in infection is not well known, and it is generally associated with other bacteria. We present a case of bilateral abscessed orchiepididymitis associated with septicemia due to Veillonella parvula and, later, to Clostridium perfringens, with the development of severe renal insufficiency and septic shock, which resolved favorably with antibiotic therapy, treatment of shock, and hyperbaric oxygen therapy. In reviewing the literature, we have not found any other case of sepsis due to Veillonella sp. associated with urological disorders. 相似文献
82.
Development and comparison of enzyme immunoassays for diagnosis of Chagas' disease using fixed forms of Trypanosoma cruzi (Epimastigotes, Amastigotes, and Trypomastigotes) and assessment of antigen stability for the three assays 下载免费PDF全文
Berrizbietia M Ndao M Gottschalk M Aché A Vásquez F Lacouture S Medina M Ward BJ 《Journal of clinical microbiology》2004,42(4):1766-1769
Three enzyme immunoassays (EIAs) for diagnosis of Chagas' disease were developed with fixed forms of Trypanosoma cruzi using a panel of 435 sera from the following groups: Venezuelan subjects positive by immunofluorescence (n = 70), Venezuelan healthy controls (n = 85), healthy Canadians (n = 166), and subjects with other parasitic diseases (n = 114). All assays achieved 100% sensitivity and reasonable specificity for amastigotes (97.6%), epimastigotes (98.3%), and trypomastigotes (99.3%). The fixed-trypomastigote assay was stable over 4 months at 4 degrees C and room temperature. These data suggest that a fixed-trypomastigote EIA may be a suitable candidate for blood bank screening. 相似文献
83.
A M Yamamoto C Mura M G Morales O Bernard R Krishnamoorthy F Alvarez 《Clinical and experimental immunology》1992,87(2):251-255
Cytochrome P450 IID6 is an autoantigen recognized by the sera of children affected with a subtype of autoimmune hepatitis. It was hypothesized that a mutation in the CYP2D6 gene could explain the autoimmune response in these patients. To examine this question, genomic DNA from peripheral lymphocytes (n = 9) and liver (n = 1) of 10 patients with anti-LKM-1 antibody was analysed by Southern blot for genetic association studies between a particular CYP2D6 haplotype and autoimmune hepatitis. In addition, a region of CYP2D6, from the same genomic DNA, was amplified by polymerase chain reaction (PCR) and digested by BstNI, in a search for the most prevalent 29B mutation, described in subjects who do not express the P450 IID6. Total RNA and proteins, prepared from the liver of an anti-LKM-1+ patient, were analysed by Northern and Western (immunoblot) blots respectively. Our results do not reveal any major structural change in the DNA of this patient at the CYP2D6 locus that could explain their autoimmune response. Corroborating this observation, no changes were noted either in P450 IID6 mRNA size or in the corresponding protein. However, these data do not exclude the possibility of subtle changes in the protein due to point mutations in critical regions that might trigger an autoimmune response. 相似文献
84.
Ibáñez L Potau N Enriquez G Marcos MV de Zegher F 《Human reproduction (Oxford, England)》2003,18(8):1565-1569
BACKGROUND: Fetal growth restraint has been associated with FSH hypersecretion in early infancy and in early post-menarche, and with reduced uterine and ovarian size in adolescence. It is unknown whether these reproductive anomalies persist, respectively, into late infancy and into the reproductive age range. METHODS: We report follow-up findings in two age groups of girls. A cohort of infants [n=26; n=10 born appropriate-for-gestational-age (AGA) and n=16 born small-for-gestational-age (SGA)], who had been studied at the age of approximately 4 months, was assessed again at the age of 12 months. A cohort of teenagers (n=28), who had been studied at the age of approximately 14 years, was assessed again at the age of approximately 18 years; this group was complemented by a transversal cohort of similar age (n=19) for a total of 47 young women (n=27 AGA; n=20 SGA). In infants, only serum FSH was measured; adolescents underwent endocrine-metabolic screening, ultrasound assessment of uterine-ovarian size, and evaluation of body composition by dual X-ray absorptiometry. RESULTS: Serum FSH levels were higher in SGA than AGA infant girls at 4 and 12 months, and higher in SGA than AGA adolescents at 14 and 18 years (all P<0.01). Longitudinal ultrasound assessments disclosed a late-adolescent increment of uterine size that was less obvious in SGA than AGA girls. In contrast, ovarian volume remained stable in both subgroups. Compilation of longitudinal and transversal results at 18 years of age corroborated the persistent reduction in the uterine size of SGA girls (by approximately 20%; P<0.005) and in their ovarian volume (by approximately 40%; P<0.0001); moreover, SGA girls displayed not only a persistent elevation of FSH (by approximately 50%; P<0.001), but also a rise of LH and fasting insulin, as well as an excess of abdominal fat (all P<0.01). CONCLUSIONS: The gynaecology of young women born SGA was found to be characterized by hypergonadotrophinaemia and by a reduced uterine and ovarian size. 相似文献
85.
86.
CD44 Isoform Expression Follows Two Alternative Splicing Pathways in Breast Tissue 总被引:1,自引:0,他引:1 下载免费PDF全文
Xavier Roca Jos L. Mate Aurelio Ariza Ana M. Muoz-Mrmol Claudia von Uexküll-Güldeband Inmaculada Pellicer Jos J. Navas-Palacios Marcos Isamat 《The American journal of pathology》1998,153(1):183-190
The repertoire of distinct CD44 protein isoforms is generated by means of alternative pre-mRNA splicing of 10 variable exons located in the central region of the CD44 gene. We have used human breast ductal carcinoma as a model to identify two alternative splicing pathways of the CD44 pre-mRNA variable region that account for the generation of all of the CD44 isoforms described in breast tissue. An alternative splicing pathway that reflects inclusion of variable exons in a gradual 3′-to-5′ fashion is evidenced in breast ductal carcinoma and its lymph node metastases. This pathway is compatible with a mechanism that generates the standard form of CD44 (devoid of variable exons) and is distinguishable from an alternative splicing pathway that involves exclusively variant exon 3 and is observable in both normal and carcinoma breast tissue. We show that both pathways are detectable in the same cell type in the breast and provide a speculative model by which these splicing routes could take place. 相似文献
87.
Enhanced molecular volume of conservatively pegylated Hb: (SP-PEG5K)6-HbA is non-hypertensive 总被引:2,自引:0,他引:2
Acharya SA Friedman JM Manjula BN Intaglietta M Tsai AG Winslow RM Malavalli A Vandegriff K Smith PK 《Artificial cells, blood substitutes, and immobilization biotechnology》2005,33(3):239-255
Recent studies have suggested that the "pressor effect" of acellular Hb is a consequence of perturbation of the macro-and microcirculatory system in multiple ways, and that PEGylation is an effective approach for controlling the same. In an attempt to confirm this concept, a new and simple thiolation mediated, maleimide chemistry-based conservative PEGylation protocol has been developed to conjugate multiple copies of PEG-chains to Hb. This approach combines the high reactivity of maleimides towards thiols with the propensity of iminothiolane to derivatize the epsilon-amino groups of proteins into reactive thiol groups, with conservation of their positive charge. One of the PEGylated products, namely (SP-PEG5K)6-HbA, that carries on an average six copies of PEG5000 chains per Hb, is non-hypertensive in hamster top load and in rat 50% exchange transfusion models. This hexa-PEGylated-Hb has (i) a hydrodynamic volume corresponding to that of an oligomerized Hb of 256kDa, (ii) a molecular radius of approximately 6.8 nm, (iii) high oxygen affinity, (iv) lowered Bohr effect, and (v) increased viscosity and colloidal osmotic pressure. These properties of (SP-PEG5K)6-HbA are consistent with the emerging new paradigms for the design of Hb based oxygen carriers and confirm the concept that the "pressor effect" of Hb is a multifactorial event. The thiolation mediated maleimide chemistry-based PEGylation protocol described here for the generation of (SP-PEG5K)6-Hb is simple, highly efficient, and is carried out under oxy conditions. The results demonstrate that a non-hypertensive PEG-Hb can be generated by conjugation of a lower number of PEG chains than previously reported. 相似文献
88.
Antikinetochore antibodies and fluorescence in situ hybridizationwith an alphoid centromeric probe were applied to the cytokinesis-blockmicronucleus (MN) assay to study the suitability of these methodologiesto detect clastogenic/aneugenic activity in isolated human lymphocytes.The chemicals selected for this study were the herbicide alachlor,the clastogen mitomycin-C (MMC), and the aneugen vinblastinesulphate (VBL). Futhermore, MN frequencies obtained from slidesstained with MayGrünwaldGiemsa (MGG) andwith the DNA fluorochrome 4', 6'diamidino-2-phenylindole (DAPI)were compared to check if the DNA-specific DAPI facilitateda more accurate recording of MN than the unspecific MGG. Theresults showed that the detection of kinetochores (KC) or centromeres(CM) within MN are equally reliable and sensitive techniquesto study the mode of action of clastogenic and aneugenic agents.The comparison of CM and KC detection in control cultures suggestedthat up to 17% of spontaneous chromosomecontaining MN may bedue to KC disruption, whereas the majority are caused by dysfunctionin other components of the mitotic apparatus. Alachlor (7.520µg/ml) and MMC (0.6 µM) acted as pure clastogenswithout aneugenic activity, inducing exclusively KC- and CM-negativeMN. VBL produced primarily KC- and CM-positive MN, in accordancewith its known mechanism of action. A comparison between CMand KC data in the VBL treatment suggested that some 7% of KC-containingMN may not be detected by the probe. The frequencies of MN weregenerally higher in slides stained with DAPI than in those stainedwith MGG, especially in controls and clastogen-treated cultures.This finding probably reflects an underestimation with MGG ofsmall, light MN indistinguishable from the cytoplasmic background.
4To whom correspondence should be addressed 相似文献
89.
Morphologic Study of the Participation of the Complement System in Hyperacute Rejection of Renal Xenotransplants 下载免费PDF全文
Jaime E. Mej¯a-Laguna Adolfo Mart¯nez-Palomo Carlos E. Biro Bibiana Ch¬vez Fernando LÌpez-Soriano Marcelo Garc¯a-Cornejo 《The American journal of pathology》1972,69(1):71-78
The role of polymorphonuclear leukocyte (PMN) and platelet infiltration in the hyperacute rejection of renal xenotransplants was studied. In a first group, a dog kidney was grafted to rabbit recipients with intact immune adherence and chemotaxis. A second group included recipients depleted of PMN's with nitrogen mustard, and in a third group, immune adherence and chemotaxis were modified by depleting the third component of complement by means of cobra venom factor. Serial kidney biopsies were studied with light and electron microscopic technics. A semiquantitative evaluation of PMN and platelet glomerular infiltration indicated that a reduction in the number of PMN's or platelets is associated with an increased survival time of the transplanted kidney. 相似文献
90.
Soluble factors released by Toxoplasma gondii-infected astrocytes down-modulate nitric oxide production by gamma interferon-activated microglia and prevent neuronal degeneration 下载免费PDF全文
Rozenfeld C Martinez R Figueiredo RT Bozza MT Lima FR Pires AL Silva PM Bonomo A Lannes-Vieira J De Souza W Moura-Neto V 《Infection and immunity》2003,71(4):2047-2057
The maintenance of a benign chronic Toxoplasma gondii infection is mainly dependent on the persistent presence of gamma interferon (IFN-gamma) in the central nervous system (CNS). However, IFN-gamma-activated microglia are paradoxically involved in parasitism control and in tissue damage during a broad range of CNS pathologies. In this way, nitric oxide (NO), the main toxic metabolite produced by IFN-gamma-activated microglia, may cause neuronal injury during T. gondii infection. Despite the potential NO toxicity, neurodegeneration is not a common finding during chronic T. gondii infection. In this work, we describe a significant down-modulation of NO production by IFN-gamma-activated microglia in the presence of conditioned medium of T. gondii-infected astrocytes (CMi). The inhibition of NO production was paralleled with recovery of neurite outgrowth when neurons were cocultured with IFN-gamma-activated microglia in the presence of CMi. Moreover, the modulation of NO secretion and the neuroprotective effect were shown to be dependent on prostaglandin E(2) (PGE(2)) production by T. gondii-infected astrocytes and autocrine secretion of interleukin-10 (IL-10) by microglia. These events were partially eliminated when infected astrocytes were treated with aspirin and cocultures were treated with anti-IL-10 neutralizing antibodies and RP-8-Br cyclic AMP (cAMP), a protein kinase A inhibitor. Further, the modulatory effects of CMi were mimicked by the presence of exogenous PGE(2) and by forskolin, an adenylate cyclase activator. Altogether, these data point to a T. gondii-triggered regulatory mechanism involving PGE(2) secretion by astrocytes and cAMP-dependent IL-10 secretion by microglia. This may reduce host tissue inflammation, thus avoiding neuron damage during an established Th1 protective immune response. 相似文献