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11.
Epidemic typhoid in vietnam: molecular typing of multiple-antibiotic-resistant Salmonella enterica serotype typhi from four outbreaks
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Connerton P Wain J Hien TT Ali T Parry C Chinh NT Vinh H Ho VA Diep TS Day NP White NJ Dougan G Farrar JJ 《Journal of clinical microbiology》2000,38(2):895-897
Multidrug-resistant Salmonella enterica serotype Typhi isolates from four outbreaks of typhoid fever in southern Vietnam between 1993 and 1997 were compared. Pulsed-field gel electrophoresis, bacteriophage and plasmid typing, and antibiotic susceptibilities showed that independent outbreaks of multidrug-resistant typhoid fever in southern Vietnam are caused by single bacterial strains. However, different outbreaks do not derive from the clonal expansion of a single multidrug-resistant serotype Typhi strain. 相似文献
12.
We investigated effects of sleep on pain-related somatosensory evoked potentials (SEP) following painful electrical stimulation of the left index finger. The biggest advantage of this method is that signals ascending through both A-beta fibers relating to touch and A-delta fibers relating to pain can be recorded simultaneously. While the subject was awake, non-painful stimulation evoked early- and middle latency components, N20, P30 and N60, at the C4 electrode, and painful stimulation evoked not only early- and middle latency components at the C4 but also later pain-specific components, N130 and P240, at the Cz electrode. During sleep, N20 and P30 did not show a significant change in amplitude, N60 showed a slight but significant amplitude reduction, and N130 and P240 significantly decreased in amplitude or disappeared, as compared with those while awake. Therefore, we speculate on the mechanisms generating each component as follows; (1) N20 and P30 are the primary components generated in SI ascending through A-beta fibers. (2) N60 is the secondary component generated in SI involving cognitive function to some degree. (3) N130-P240 are the pain-specific components ascending through A-delta fibers, and closely related to cognitive function, because they were much affected by consciousness, different from the components ascending through A-beta fibers. 相似文献
13.
A dynamic pattern analysis of coordination between breathing and rhythmic arm movements in humans 总被引:6,自引:0,他引:6
An insertion (I)/deletion (D) polymorphism in the angiotensin 1-converting enzyme (ACE) gene has, in some studies, been associated with increased risk for Alzheimer's disease (AD), and functionally the enzyme has been implicated in the degradation of amyloid beta protein (Abeta). We have investigated the frequency of the I/D polymorphism in a clinic-based and autopsy-confirmed series of cases of AD, and investigated what impact the I/D polymorphism in ACE gene might have on the extent of Abeta and tau pathology in the frontal cortex in the autopsy-confirmed series. We found no differences in I/D allele or genotype frequencies between the clinic-based and autopsy-confirmed AD cases, or between the pooled clinic-based and autopsy-confirmed AD cases and a series of normal control subjects. Moreover, Abeta (Abeta(40) and Abeta(42)) load, tau load or extent of amyloid angiopathy did not differ between D/D, I/D and I/I genotype groups, though Abeta(42) load tended to be higher in bearers of I/I genotype (compared to D/D genotype). Neither age at onset nor duration of illness differed according to genotype. We conclude therefore that the frequency of ACE I-allele is not increased in AD and, in autopsy-confirmed AD cases, possession of the ACE I allele has no impact upon the pathology of AD, at least in terms of the amount of Abeta or tau deposited in the brain. 相似文献
14.
Foamy viruses are nonpathogenic retroviruses that offer unique opportunities for gene transfer into various cell types including hematopoietic stem cells. We used a simian foamy virus type 1 vector (SFV-1) containing a LacZ reporter gene with a titer of 1-5 x 10(6) viral particles/ml that was free of replication-competent retrovirus to transduce human umbilical cord blood CD34+ cells. Transduced CD34+ cord blood cells were transplanted into NOD/SCID mice and plated in serum-free methylcellulose culture to determine the transduction efficiency of human hematopoietic progenitor cells. A transduction efficiency of about 20% was obtained. At 6-10 weeks posttransplantation, human hematopoietic cell engraftment and marking were determined. Marrow from transplanted mice demonstrated human cell engraftment by the presence of human (CD45+) cells containing both CD19+ lymphoid and CD33+ myeloid cells. Serial sampling of NOD/SCID bone marrow revealed the presence of 6.7-14.0% CD45+ cells at 6 weeks posttransplant as compared to 3.6-27.2% CD45+ cells at 9-10 weeks posttransplant. Human progenitors examined from NOD/SCID bone marrow cells 9 weeks posttransplant revealed from 7.4 to 25.9% of the colonies exhibiting X-gal staining. Our study demonstrates the ability of a simian foamy virus vector to transduce the SCID-repopulating cell and offers a promising new gene delivery system for use in hematopoietic stem cell gene therapy. 相似文献
15.
Paul R. Atkinson Jeffrey L. Mahon John Dupre Calvin R. Stiller Morris R. Jenner Terri L. Paul Clement I Momah 《Journal of autoimmunity》1990,3(6):793-799
Although cyclosporine A (Cy-A) is effective in modifying the initial course of newly diagnosed insulin dependent diabetes mellitus (IDDM) it has a number of side effects, particularly renal, which limit its use. In this study we investigated the potential synergistic effects of bromocriptine (BCR) therapy in treating patients with newly diagnosed IDDM. Three groups of patients were treated: (1) fourteen patients on Cy-A who required a decrease in their dose due to elevated creatinine; (2) four newly diagnosed patients whose initial therapy consisted of low dose (5 mg/kg/day) Cy-A and 10 mg/day of BCR; (3) eight patients whose glucagon-stimulated connecting-peptide (C-peptide) levels were greater than 0.3 nmol/l but whose insulin requirements were over 0.3 U/kg/day and whose Cy-A was to be discontinued. The results suggest that there was no statistically significant difference in stimulated C-peptide, glycosylated haemoglobin, daily insulin dose or serum creatinine. However, the trend suggested that BCR may have some protective effect on preserving endogenous insulin secretory capacity, although glycosylated haemoglobin and daily insulin dose increased. The results do not suggest that patients with newly diagnosed IDDM significantly benefit from concurrent BCR and Cy-A therapy. 相似文献
16.
Quy N. Diep Thomas Bøhmer Jan I. Holme Ansgar Torvik Olav T. Storrøsten Christian W. Loennecken Per Monstad Egil Jellum 《Pharmacy World & Science》1993,15(5):225-229
Long-term treatment with pivampicillin and pivmecillinam for 6–24 months in five adults and one child reduced the total serum carnitine concentration to 3.7–14 mol/l (reference value: 25–66 mol/l). Muscle carnitine was reduced to 0.3–0.7mol/g wet weight (reference value: 3–5mol/g) in two cases. All patients had muscle symptoms with weakness, asthenia and pains. One showed signs of carnitine depletion in the liver with increased secretion of dicarboxylic acids (C6, C8, C10) in urine and limited ketone body formation during prolonged fasting. Serum carnitine increased slowly after cessation of therapy and reached normal concentrations after 6–12 months. All symptoms caused by carnitine depletion disappeared. This was achieved on a normal diet without carnitine supplementation. 相似文献
17.
Ritsuko Akiyama Kunyan Kuang Pablo A. Chiaradía Calvin W. Roberts Jorge Fischbarg 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1997,235(6):384-387
Background: Anterior chamber miotic solutions are widely used in ophthalmic surgery to induce pupillary contraction. We investigated whether the acetylcholine, carbachol, or mannitol present in perfusing solutions can affect corneal endothelial function. Methods: Freshly dissected deepithelized rabbit corneas were mounted in a Dikstein-Maurice chamber at 36 °C. The endothelial sides were perfused with six solutions: (A) 55 mM (1%) acetylcholine Cl plus modified balanced salts; (B) control for A, with acetylcholine Cl replaced by sucrose; (C) 0.55 mM (0.01%) carbachol Cl plus balanced salts; (D) balanced salts solution (BS; control for C); (E) 3% mannitol plus modified balanced salts; and (F) modified balanced salts (control for E, with mannitol replaced by sucrose). Corneal thickness was followed for 3 h in each experiment. The effect of solution E did not differ from that of solution F. Results: The carbachol-containing solution produced a small increase in corneal thickness compared to the control solution, while the acetylcholine-containing solution resulted in corneal thickness lower than that in control preparations. Conclusion: From these data, acetylcholine is harmless to the endothelium, and may actually stimulate its fluid pump mechanism. Carbachol, on the other hand, appears to have a detrimental effect. 相似文献
18.
19.
Duval F Mokrani MC Bailey P Corrêa H Crocq MA Son Diep T Macher JP 《Dialogues in clinical neuroscience》2000,2(3):299-308
The present study was conducted in order to investigate the relationships between central noradrenergic (NA) and serotonergic (5-HT) function and clinical characteristics of a major depressive episode according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. We measured growth hormone response (ΔGH) to clonidine (CLO) (an α2 NA agonist), as an index of central NA function, and prolactin response (APRL) to d-fenfluramine (d-FEN) (a specific 5-HT releaser/uptake inhibitor), as an index of central 5-HT function, in 53 medication-free depressed inpatients. On the basis of their CLO and d-FEN test responses, patients were classified into 4 groups. Group 1 (blunted ΔPRL(d-FEN) alone [11 %]) was characterized by a recent violent suicide attempt, a high degree of medical damage, and mild anxiety. Group 2 (blunted ΔGH(CLO) alone [32%]) was characterized by an absence of a history of suicide attempt and by severe anxiety. Group 3 (combination of blunted ΔGH(CLO) and APRL(d-FEN) [18%]) was characterized by a history of suicide attempts, total duration of the illness of over W years, age over 40 years, and more than 3 previous hospitalizations. Group 4 (no abnormality [39%]) had no specific clinical profile. These results suggest that, in depression, specific psychopathological features may be linked to 5-HT and/or NA dysfunction. However, our results also suggest that NA and/or 5-HT dysfunction are less likely to be the primary cause of mood disorders but are more indicative of failure of compensatory mechanisms involved in affective homeostatic processes. 相似文献
20.
Jasbir S. Johal James W. Thorp Calvin E. Oyer 《Pediatric and developmental pathology》1998,1(5):433-437
We report a neonate with neonatal hemochromatosis (NH), renal tubular dysgenesis (RTD), and hypocalvaria. NH is a fatal condition
of the newborn, characterized by severe idiopathic liver failure of intrauterine onset and siderosis, intra- and extrahepatic,
with sparing of the reticuloendothelial system. RTD is characterized by short, abnormally developed cortical tubules that
lack proximal tubule differentiation. Although both NH and RTD have been reported as entities with a genetic component, similar
findings can be secondary to in utero insults. Hypocalvaria has been reported in association with fetal hypoxia including
that secondary to angiotensin converting enzyme inhibitors. This 38-week-old infant died at 8.5 h. The small nodular liver
weighed 44 g. Grossly, the kidneys were normal. Hypocalvaria was present. Microscopically, the hepatic parenchyma was distorted
by fibrous tracts, proliferation of bile ducts, and abundant iron deposition in hepatocytes. Extrahepatic siderosis in the
pancreas, myocardium, and other organs was consistent with NH. Proximal convoluted tubules were not seen on routine stains
and markers for proximal tubules were negative. Previous reports have linked NH with RTD and RTD with hypocalvaria. This infant
had all three of these rare conditions, which have been hypothesized or shown to be due to genetic factors, hypoxia, or drugs.
The etiology in this case is unknown.
Received May 20, 1997; accepted August 15, 1997. 相似文献