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51.
Having in mind the significant decrease of urinary kallikrein in rat with renal hypertension and in humans with essential hypertension, the effects of furosemide on kininogenase activity has been studied in urine of normal and hypertensive rats which received tap water or a 1% NaCl solution for drinking. Administration of 20 mg furosemide which produces maximal diuretic effect in normal rats, induced in these animals a 150–200% increase of the excretion of this enzyme after 8 hours, when compared to the activity measured before giving the drug. This increase which is observed in the normal rats drinking either water or a 1% NaCl solution shows a significant correlation with the excretion of sodium, potassium and water. In hypertensive rats, in 7 or 9 cases, an increase of kallikrein excretion (200–600%) is observed, which does not reach the levels of excretion in normal untreated rats. Furosemide did not produce increase of urinary kallikrein in hypertensive rats drinking 1% NaCl solution.  相似文献   
52.
Serum amyloid A protein (SAA) elevation accompanies induction of secondary amyloidosis in mice given Mycobacterium butyricum in Freund adjuvant. The synthesis of SAA by cultured hepatocytes is induced by a macrophage-derived mediator, which has been identified as interleukin 1. In these studies, SAA synthesis has been used as an index of macrophage activation to examine the in vivo response of mice to challenge with seven different mycobacteria and with synthetic analogs of the immunoadjuvant N-acetylmuramyl-L-alanyl-D-isoglutamine [MDP(L-D)]. SAA synthesis was stimulated by administration (by the intraperitoneal route) of the mycobacteria dissolved in saline, with Mycobacterium vaccae being the most active and Mycobacterium leprae being the least stimulatory. MDP(L-D), which is the minimal structure (molecular weight, 492) able to substitute for mycobacteria in Freund adjuvant, stimulated SAA synthesis, whereas the MDP(D-D) isomer was inactive. The butyl ester of MDP, which induces no detectable pyrogenicity but retains adjuvanticity, required a 100-fold greater dosage than MDP(L-D) in stimulating SAA synthesis. Amyloidosis was detected histologically only when active SAA inducers MDP(L-D), M. vaccae, and M. butyricum, were administered in incomplete Freund adjuvant, with amyloid-enhancing factor. These studies demonstrated that SAA elevation was a sensitive in vivo marker of the capacity of antigens to stimulate macrophages to produce interleukin 1. A point of considerable relevance to the human use of MDP was the observation that repeated injections of the adjuvant MDP in saline did not induce secondary amyloidosis.  相似文献   
53.
The afa gene clusters encode afimbrial adhesins (AFA) that are expressed by uropathogenic and diarrhea-associated Escherichia coli strains and belong to a family of hemagglutinins recognizing the Dr blood group antigen as a receptor. This family so far includes AFA-I and AFA-III as well as the Dr and F1845 adhesins (B. Nowicki, A. Labigne, S. Moseley, R. Hull, S. Hull, and J. Moulds, Infect. Immun. 58:279-281, 1990). Reported in this work is the genetic organization of the afa-3 gene cluster cloned from a uropathogenic E. coli strain (A30) which expressed a subtype of AFA designated AFA-III. The amino acid sequence of AFA-III was deduced from the nucleotide sequence of the afaE3 gene and was found to be highly homologous to that of the Dr adhesin (98.1% identity). A polymerase chain reaction assay was developed to detect the presence of afa-3 gene clusters in E. coli strains. Study of the genetic support of the afa-3 gene clusters in the strains which showed positive amplification revealed that they were always located on large, 100-kb plasmids whether the strains originated from patients with cystitis or with diarrhea. Moreover, the cloned afa-3 gene clusters from A30 and from the diarrhea-associated strain AL845 appeared to be carried by 9-kb plasmid regions which displayed a similar genetic organization. Chloramphenicol was reported to be a potent inhibitor of receptor binding by the Dr adhesin (Nowicki et al., Infect. Immun. 58:279-281, 1990). AFA-III expressed by strains AL845 and AL847 appeared to mediate, like the Dr adhesin, chloramphenicol-sensitive hemagglutination, whereas AFA-III produced by A30 conferred chloramphenicol-resistant adherence. A comparison of the sequences of these four proteins indicated that the amino acid at position 52 of the processed AFA could be part of the receptor-binding domain.  相似文献   
54.
Background: Fabry disease is an X linked lysosomal storage disease caused by deficiency of the lysosomal enzyme α-galactosidase A. This leads to accumulation of globotriaosylceramide in nearly all tissues, including the blood vessels, kidney, myocardium, and nervous system. Symptoms often begin in childhood and include acroparaesthesia, with burning or tingling pain that spreads from the extremities to more proximal sites.

Aims: This study set out to evaluate pain and its influence on quality of life in patients with Fabry disease receiving enzyme replacement therapy (ERT) with agalsidase alfa.

Methods: Data were obtained from the Fabry Outcome Survey. Pain was measured using the Brief Pain Inventory (BPI), and health-related quality of life (HRQoL) was documented with the European Quality of Life Questionnaire (EQ-5D).

Results: The mean (SD) score for "pain at its worst" on the BPI prior to ERT was 5.1 (2.7). One year after commencement of ERT, this had improved by 0.5, and improved by a further 0.6 after 2 years (p<0.05). Similar statistically significant improvements were seen for "pain on average" and "pain now" after 2 years of ERT. The mean HRQoL utility score prior to ERT was 0.66 (0.32). After 12 months of treatment with agalsidase alfa, this had improved to 0.74 (0.26; p<0.05); this improvement was maintained after 2 years.

Conclusions: ERT with agalsidase alfa significantly reduces pain and improves quality of life in patients with Fabry disease.

  相似文献   
55.
As a result of disposal problems inherent in the use of mercury compounds, many laboratories have considered using copper sulfate as a substitute for mercuric chloride in polyvinyl alcohol (PVA) preservative. The primary use for PVA-preserved specimens is the permanent stained smear, the most important technique for the identification of intestinal protozoa. A comparison of organism recovery and morphology was undertaken with PVA containing either copper sulfate or mercuric chloride base. Paired fecal specimens (417 pairs) were collected and examined with the Formalin-ether concentration and Trichrome stain techniques. Numbers of organisms recovered and helminth egg and protozoan morphology were assessed from the concentration sediment. Morphology, clarity of nuclear and cytoplasmic detail, overall color differences, and the ease or difficulty in detecting organisms in fecal debris were assessed from the permanent stained smear. No significant differences were found in the numbers and morphology of organisms seen in the concentration sediment. However, when the trichrome stain was used, the overall morphology of the intestinal protozoa preserved in PVA with copper sulfate was not equal to that seen with PVA with mercuric chloride. We do not recommend switching from mercuric chloride base to copper sulfate base unless that is the only option available for the preparation of permanent stained smears.  相似文献   
56.
B cell neoplasms present heterogeneous patterns of lymphoid organ involvement, which may be a result of the differential expression of chemokine receptors. We found that chemokine receptor (CCR)7, CXC chemokine receptor (CXCR)4, or CXCR5, the main chemokine receptors that mediate B cell entry into secondary lymphoid tissues and their homing to T cell and B cell zones therein, were highly expressed in B malignancies with widespread involvement of lymph nodes. Conversely, those pathologies with little or no nodular dissemination showed no expression to very low levels of CCR7 and CXCR5 and low to moderate levels of CXCR4. These findings provide evidence for the role of CCR7, CXCR4, and CXCR5 in determining the pattern of lymphoid organ involvement of B tumors. Functional studies were performed on B malignancies expressing different levels of CCR7, CXCR5, and CXCR4. Multiple myeloma (MM) cells did not express CCR7 nor CXCR5 and did not migrate in response to their ligands; a moderate expression of CXCR4 on MM cells was accompanied by a migratory response to its ligand, CXCL12. By contrast, cells from B cell chronic lymphocytic leukemia (B-CLL) expressed the highest levels of these chemokine receptors and efficiently migrated in response to all ligands of CCR7, CXCR4, and CXCR5. In addition, the migration index of B-CLL cells in response to both of the CCR7 ligands correlated with the presence of clinical lymphadenopathy, thus indicating that the high expression of functional chemokine receptors justifies the widespread character of B-CLL, representing a clinical target for the control of tumor cell dissemination.  相似文献   
57.
The mass fraction of certain elements was measured in isolated granulocytes and isolated granulocyte granule fractions from patients with active inflammatory arthritides (N=6) and healthy controls (N=6). The patients had significantly increased amounts of Ca in the granulocytes, in the specific and light azurophil granules, but normal Ca amounts in the dense azurophil granules. Sr was below the detection limit in the granulocytes and granule fraction from controls, but it appeared in high concentrations in the granulocytes and all granule fractions from the patients. The patients had considerably increased granulocyte amounts of Mn but only slightly increased Mn concentrations in the specific granules. Mn was not detectable in azurophil granules from patients and controls. A prominent accumulation of Fe was seen in the granulocytes from the patients, together with an Fe accumulation in the specific granules. Fe was below the detection limit in azurophil granules from patients and controls. The patients had reduced granulocyte Zn and reduced amounts of Zn in the dense and light azurophil granules but normal Zn amounts in the specific granules. The results obtained indicate that (1) the granulocyte accumulation of Ca, Sr, and Fe observed during chronic inflammation is associated with corresponding granule accumulation of these metals; (2) the considerable Mn accumulation in granulocytes during inflammation is not localized in their granules; and (3) the granule subpopulations differ in their capacity to store certain metals.  相似文献   
58.
FOXL2 mutations cause gonadal dysgenesis or premature ovarian failure (POF) in women, as well as eyelid/forehead dysmorphology in both sexes (the 'blepharophimosis-ptosis-epicanthus inversus syndrome', BPES). Here we report that mice lacking Foxl2 recapitulate relevant features of human BPES: males and females are small and show distinctive craniofacial morphology with upper eyelids absent. Furthermore, in mice as in humans, sterility is confined to females. Features of Foxl2 null animals point toward a new mechanism of POF, with all major somatic cell lineages failing to develop around growing oocytes from the time of primordial follicle formation. Foxl2 disruption thus provides a model for histogenesis and reproductive competence of the ovary.  相似文献   
59.
In vitro fertilization (IVF) and embryo transfer (ET) appear to constitute a revolution in the reproductive sciences rather than merely a new technique in the treatment of sterility. Principle of IVF: IVF accomplishes in vitro the process than normally occurs in the oviduct between the ovulation of oocyte II and embryo implantation in the endometrium. This 4 day period (under normal conditions in the woman) involves 4 steps: recovery, fertilization, segmentation and transport. Performance of IVF: Recovery of the oocytes: The oocytes are recovered under celioscopic or echographic observation when they have completed cytoplasmic maturation and their first meiosis. A precise monitoring of ovulation (spontaneous or induced) should be performed using estrogen and LH assays. IVF provides an opportunity for evaluating the methods of ovulation induction and monitoring, as a function of the maturation of the oocytes recovered. Fertilization: When the oocyte has achieved maturing after several hours of incubation, fertilization is obtained 15 h contact with washed and capacitated spermatozoa (100 000/ml). This step is highly dependent on gametocyte quality: oocyte maturity and fecundity of spermatozoa, which can be estimated from the percentage of survival in the insemination medium. Segmentation occurs in culture at pH 7.28 in the presence of 5 per cent CO2 at 37 degrees C (pronucleus 15th, 2 blastomeres 26 h, 4-8 blastomeres 52 h). Embryo transfer is carried out when an embryo is present at 52 h. Only 1/10 of the embryo transfers result in successful implantation, which depends on the quality of the embryo; the quality can only be indirect criteria.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
60.
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