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111.
Both celiac disease and inflammatory bowel disease (IBD) are characterized by chronic diarrhea and the presence of distinct (auto)antibodies. In the present study we wanted to determine the prevalence of serological markers for inflammatory bowel disease, i.e., perinuclear antineutrophil cytoplasmic antibodies (pANCA) and/or anti-Saccharomyces cerevisiae antibodies (ASCA), in 37 patients with biopsy-confirmed celiac disease (Marsh IIIb/c). The majority of the patients was positive for IgA (auto)antibodies typically associated with celiac disease, i.e., antiendomysium antibodies (EMA) (86.5%), antigliadin antibodies (AGA) (73%), and antirecombinant human tissue transglutaminase antibodies (rh-tTGA) (86.5%). Four patients with selective IgA deficiency could be identified by analyzing EMA, AGA, and rh-tTGA for the IgG isotype. The prevalence of pANCA and ASCA, markers that are used for IBD, was unexpectedly high in our cohort of patients with celiac disease: 8 patients were positive for pANCA (IgG) and 16 patients were positive for ASCA (IgG and/or IgA). These results indicate that the presence of pANCA or ASCA in the serum of patients with chronic diarrhea does not exclude celiac disease. A prospective study is required to determine whether pANCA and/or ASCA identify patients at risk for developing secondary autoimmune disease.  相似文献   
112.
Chemokines are a superfamily of small chemotactic proteins. While increased levels of interleukin-8 have been measured in serum and urine during urinary tract infection, little is known about other chemokines in this condition. Monocyte chemoattractant protein (MCP)–1, macrophage inflammatory protein (MIP)–1, MIP-1 and interferon- inducible protein (IP)–10 were measured in 30 patients with culture-proven urosepsis during a 3-day follow-up and in 11 healthy humans after intravenous injection of endotoxin (4 ng/kg). Urine and serum levels of MCP-1, MIP-1, and IP-10, but not of MIP-1, were elevated in patients on admission, and decreased after initiation of antibiotic treatment. Endotoxin administration to healthy subjects induced increases in plasma and urine concentrations of all four chemokines. These data indicate that clinical and experimental gram-negative infection in humans is associated with enhanced production of chemokines that act mainly on mononuclear cells and that these chemokines are at least in part locally produced.  相似文献   
113.
We studied the presence of Natural antibodies in plasma samples from individual birds from selected chicken lines at young and old age. Binding, specificity, and relative affinity to various antigens were determined in plasma from non-immunized female chickens at 5 weeks of age, and in plasma obtained from the same chickens one year later using indirect two-step ELISA. Birds were from three different lines. The lines were divergently selected for either high (H line) or low (L line) antibody titers to Sheep Red Blood Cells at 5 weeks of age, next to a random bred control (C line). Binding of plasma immunoglobulins (Ig) from all three lines was found with chicken-egg-white protein (CEP), ovalbumin (OVA), myoglobin (MYO), thyroglobulin (THYRO), keyhole limpet hemocyanin (KLH), bovine serum albumin (BSA), and transferrin (TRANS). Significantly higher binding to most antigens was found with plasma Ig from adult birds from the H line as compared to plasma Ig from the L line, whereas binding of plasma Ig from C-line birds was in between or similar to the H or L line, respectively. Binding of Ig to all antigens in all three lines was significantly higher in plasma obtained at one year of age as compared to plasma obtained at 5 weeks of age. A competitive ELISA with homologous and heterologous antigens was used for determining specificity of the antigen-binding antibodies. Nai;ve plasma samples were characterized by a broad binding to all antigens tested. Inhibition of binding to specific antigens was possible with a broad range of heterologous antigens, but highest competition of binding was obtained with homologous antigen. Both linear regression analysis of serial dilutions of the plasma Ig binding the antigens, as well as competitive ELISA with homologous antigen indicated that plasma Ig from the H line and plasma Ig from the L line had similar affinity characteristics to the antigens tested with the exception of OVA and KLH. Pooled non-immune plasma from H line birds bound to CEP, OVA, THYRO, TRANS, MYO, KLH, and salt-precipitated extracts and supernatants of extracts from chicken heart, spleen, liver, brain, bursa, thymus, and kidney, respectively, as determined by Western blotting. The increasing presence of antibodies in nai;ve chicken plasma binding heterologous and homologous (tissue) antigens indicates the presence of Natural antibodies in poultry. Apart from age, increasing levels of Natural antibodies may be related with the genetically based magnitude of specific antibody levels in the chicken lines studied.  相似文献   
114.
Acute coronary syndromes (ACS), including unstable angina (UA) and acute myocardial infarction (MI), are clinical manifestations of a progressive atherosclerotic process. Antibodies (Ab) to heat shock proteins (hsp) have been reported to be associated with atherosclerosis. Blood samples from 35 patients with ACS and 20 healthy volunteers were tested for Ab to human hsp60 by an enzyme-linked immunosorbent assay (ELISA). Levels of specific serum Ab against hsp60 were significantly elevated in patients with ACS when compared to clinically healthy subjects. To determine the antigenic determinants recognized by these Ab, antibody binding to seven peptides, selected from the hydrophilic and acrophilic regions of the human hsp60 molecule, was assessed. Despite the individual variation in the immune response among patients, one immunodominant region was revealed corresponding to the hsp60 (409-424) peptide. The identification of this epitope may be important for understanding the function of this protein in the atherosclerotic process.  相似文献   
115.
Tetraarylsuccinonitriles 2a – e were synthesized via oxidative dimerization of diarylacetonitriles 1a – e in basic media. The thermal decomposition of 2 results in two identical cyanodiarylmethyl radicals 3 . Both 1H and 13C NMR analyses of 1a – e and 2a – e and ESR spectra of 3a – e are presented and discussed. The results of ESR measurements provide a plausible explanation for the different reactivity of cyanodiarylmethyl radicals 3a – e in free radical polymerization.  相似文献   
116.
Beta-mannosidosis is an autosomal recessive lysosomal storage disease resulting from a deficiency of the lysosomal enzyme beta-mannosidase. The clinical manifestations of this disease in reported human cases are very heterogeneous ranging from relatively mild to moderately severe. This is in contrast with the severe prenatal onset seen in ruminant beta-mannosidosis. In humans, mental retardation, hearing loss, frequent infections, and behavioral problems are relatively common. Dysmorphology and skeletal involvement such as those seen in ruminants are unusual. The purpose of this study is to determine the range of clinical expression in human beta-mannosidosis resulting from null mutations. We determined that the beta-mannosidase gene consists of 17 exons. Intron-based PCR primers were designed and used to amplify each of the exons in genomic DNA isolated from patient fibroblasts. We identified two patients with null mutations. Results of the analysis showed that one patient was heterozygous for nonsense mutations G334T (E83X) in exon 2 and C1363T (Q426X) in exon 10, resulting in truncation of the deduced peptide sequence from 879 to 82 and 425 amino acids, respectively. The second patient was homozygous for a deletion mutation in exon 11 (1541delAT). This deletion causes a reading frame shift and 26 out of frame amino acids before a stop codon occurs in exon 12, resulting in truncation of the deduced peptide sequence from 879 to 510 amino acids. Because disease presentation in these patients with null mutations is very variable, ranging from mild to severe, we conclude that beta-mannosidosis in humans may indeed be milder than typical of other lysosomal storage disorders.  相似文献   
117.
Although the morbidity and mortality associated with invasive fungal infections in transplant recipients is high, the optimal approach to antifungal prophylaxis is controversial. Most fungal infections occur shortly after the trans- plantation during maximum immunosuppression and are caused by Candida or Aspergillus spp. Nonspecific strategies for prevention do not differ from those used in other patients at risk. They consist mainly of a reduction in risk factors, such as removal of plants from around the patient, separation of the patient from the vicinity of construction sites or improvement in hospital care by isolation and careful nursing of the patient, with strict hygiene. A more controversial issue is primary antifungal chemoprophylaxis, since there are few well designed trials of this intervention, and most of the patients studied have had haematological diseases. Orally administered antifungal drugs that are not absorbed through the gastrointestinal tract have not shown any evidence of a prophylactic effect to date. Controlled trials of systemically administered or orally absorbed drugs in specific transplant recipients have, however, proved effective. In allogeneic and autologous bone marrow transplants, fluconazole 400 mg/day was effective when administered from the conditioning treatment period through the neutropenic period. In liver transplant recipients, either fluconazole 400 mg/day for 10 weeks or liposomal amphotericin B 1 mg/kg/day for 5 days significantly reduced the incidence of invasive fungal infections. However, one must be aware of the risk of fluconazole-resistant fungi and the possibility of selection. In patients with a history of previous fungal infection, secondary prophylaxis may be of value, although data are limited. For recipients of transplants other than bone marrow or liver, there are insufficient data to recommend general prophylaxis.  相似文献   
118.
The molecularin vitro association of radiolabelled chloroquine (CQ) with both normal resting and inflammatory polymorphonuclear leucocytes (PMNs) was measured. For this purpose a suitable ligandassocation assay was developed to measure the cell association and the intracellular concentration of CQ. Under the influence of inflammatory stimuli PMNs display altered interaction with CQ. The intracellular concentration of CQ is reduced with 30 to 40% under inflammatory (disease) states when compared with non-inflammatory conditions. The mechanisms of CQ-PMN interaction associated with these altered intracellular concentrations of CQ are considered, with particular attention to the effects of rheumatic disease. Association experiments of CQ with PMNs performed in the presence of different established transport inhibitors showed that both diffusive uptake and carrier-mediated transport are involved in the cell accumulation of CQ in inflammatory PMNs. From these results, emphasis is given to three explanations for the decrease of the intracellular CQ concentration in inflamed PMNs:
  1. the expansion of the PMN volume under inflammatory conditions;
  2. the cytoplasmic or lysosomal pH changes and activation of the PMN Na+/H+ antiport by inflammatory stimuli; and
  3. the exocytic release of the granules (degranulation).
Our data suggest that all these mechanisms, based on the events involved in inflammatory responses, may be involved in the decrease of the intracellular CQ concentration in inflammatory PMNs.  相似文献   
119.
The transport (J) of waste products across dialyzer membranes is known to be proportional to the blood inlet concentration (Cbi) according to J = KCbi, where K is the clearance. For solutes present on both sides of the membrane, like sodium chloride, it has been shown that under certain conditions the transport rate will depend linearly also upon the dialysis fluid inlet concentration Cdi according to J = KbCbi -KdCdi. Kb and Kd are generalized clearances, which depend upon flow rates and membrane permeability but are independent of the concentrations. We have extended the results of Ross et al. in three ways. First, they only considered ultrafiltration (UF) that is equally distributed along the dialyzer. This is an unrealistic assumption, especially in hemodiafiltration and hemofiltration treatments with large UF rates (Quf) leading to large pressure drops along the dialyzer. Our approach allows for an arbitrary UF distribution. Second, it was possible to incorporate the more realistic model of Villaroel et al. for the local combination of diffusion and convection. Finally, we allow an arbitrary distribution of blood among the different fibers. All of these results are valid in both cocurrent and countercurrent configurations. With a sieving coefficient of 1, a good approximation for small solutes, we were also able to show that Kd = Kb - Quf, irrespective of the UF distribution along the dialyzer. This is an important result that, for example, provides a theoretical foundation for allowing a nonzero Quf in conductivity based clearance measurements.  相似文献   
120.
We sought to investigate associations between knowledge about the disease and sick leave, health complaints, functional limitations, adaptation and perceived control. Patients with asthma (n = 101) and COPD (n = 64) underwent lung function tests and completed questionnaires. In addition, all were asked the question: ‘what is the diagnosis of your disease?’, with the response categories: ‘asthma’ and ‘COPD (chronic bronchitis or emphysema)’. Thirty-five percent of the asthma patients and 30% of the COPD patients did not know their correct diagnosis. Sick leave was not associated with knowledge about the disease in asthma and COPD. In asthma, much knowledge about management of the disease was associated with better adaptation (P = 0.01) and less perceived control over health by external factors (P = 0.02). Knowing the correct diagnosis was associated with less control over health by powerful others (P = 0.02). For COPD, more knowledge about management of the disease was associated with better adaptation (P = 0.02) and less control over health by internal factors (P = 0.01). Knowing the correct diagnosis was associated with less control over dyspnea at work (P = 0.01).  相似文献   
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