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71.
Bacterial pyrogens, capable of penetrating dialyzer membranes, are responsible for a systemic inflammatory reaction in hemodialysis patients. Dialyzer reuse, involving rinsing of the dialyzer with pyrogen-containing water, may exacerbate this situation. Studies of the mechanism of action of endotoxin suggest that it irreversibly damages the vascular endothelium. The novel endotoxin removal method described here, is based on affinity-binding of endotoxin by the adsorbent ClarEtox, a USP Class VI-certified resin that is the active component of the medical device DialGuard. Under standard hemodialysis operating conditions, challenge of DialGuard with Pseudomonas maltophilia supernatant-spiked dialysate, containing 35-193 EU/ml endotoxin, resulted in endotoxin levels below 0.05 EU/ml in the treated dialysate. DialGuard was able to decrease endotoxin concentrations in the dialysate from a range of 2.39-8.49 to <0.005 EU/ml. DialGuard supports high fluid velocities at low back pressures and can be sanitized using the heat sanitization cycle of hemodialysis machines. DialGuard offers a simple, user-friendly way to reduce the concentration of endotoxin in dialysate and water for dialysis at a low cost.  相似文献   
72.
OBJECTIVE: To investigate the relationship between antiprothrombin (aPT) and antiannexin V (aANX) autoantibodies of IgG isotype and thrombosis in patients with systemic autoimmune diseases. To compare the clinical relevance of these antibodies to that of anticardiolipin (aCL), anti-beta2-glycoprotein I antibodies (anti-beta2-GPI), and lupus anticoagulant (LAC). METHODS: Serum IgG aPT, aANX, aCL, and anti-beta2-GPI levels were measured by solid phase enzyme immunoassay in the sera of 70 patients with systemic autoimmune diseases, 35 with antiphospholipid syndrome (APS) and 35 without APS. Medical records were analyzed, and associations of the antibodies with clinical features of APS were assessed. RESULTS: Patients with APS had higher frequency of aPT (p = 0.001) and aANX (p = 0.002) compared to patients without APS. Thrombotic events occurred more frequently in those with aPT or aANX than those without (p = 0.005, p = 0.006, respectively). The presence of aPT and aANX was found to be highly specific for APS. CONCLUSION: Measurement of aPT and aANX antibodies may be of value in confirming the diagnosis of APS, and in evaluating risk of venous and arterial thrombosis in patients with systemic autoimmune diseases.  相似文献   
73.
OBJECTIVE: The aims of the present study were (a) to examine the occurrence of 21-hydroxylase gene (CYP21) mutations in patients with unilateral and bilateral adrenal incidentalomas and (b) to correlate the results of mutation screening with hormonal parameters of 21-hydroxylase deficiency. DESIGN: The frequency of the eight commonly occurring CYP21 mutations in blood DNA samples of 19 patients with bilateral, as well as in blood and tumoral tissue DNA samples of 31 patients with unilateral adrenal incidentalomas, was determined. In all patients, hormonal evaluation for 21-hydroxylase deficiency was performed using measurements of basal and ACTH-stimulated plasma 17-hydroxyprogesterone (17-OHP) concentrations. METHODS: Blood and tumoral DNA samples were analyzed by allele-specific PCR for the detection of the eight commonly occurring CYP21 mutations (deletion/large gene conversion, intron 2 splicing, Ile172Asn, exon 6 cluster, Val281Leu, Leu307insT, Gln318Stop and Arg356Trp mutations). Plasma 17-OHP concentrations were measured by radioimmunoassay. RESULTS: Of the 19 patients with bilateral adrenal incidentalomas, one patient had homozygous (Val281Leu) and three patients had heterozygous germline CYP21 mutations (Val281Leu in two cases and Arg356Trp in one case). Heterozygous germline CYP21 mutations were also detected in five of the 31 patients with unilateral adrenal incidentalomas (Ile172Asn in three cases and Val281Leu in two cases). Mutation screening of tumoral DNA in unilateral incidentalomas showed the presence of corresponding germline mutations but no additional somatic mutations were found. ACTH-stimulated plasma 17-OHP concentrations were above 1500 ng/dl in all patients with bilateral incidentalomas who had homozygous and heterozygous CYP21 mutations, but heterozygous carriers with unilateral incidentalomas had highly variable ACTH-stimulated plasma 17-OHP levels (between 111 and 1705 ng/dl). CONCLUSIONS: These results suggest a similar frequency of germline CYP21 mutations in patients with bilateral and unilateral adrenal incidentalomas (21.1% and 16.1% respectively). Therefore, it cannot be ruled out that, in at least some patients, CYP21 mutations may play a role in the pathomechanism of bilateral and unilateral adrenal incidentalomas. However, the lack of clear association of CYP21 mutations with increased ACTH-stimulated plasma l7-OHP response, especially in patients with unilateral incidentalomas, suggests that the effect of CYP21 mutations on adrenocortical tumor formation may also involve mechanism(s) independent of ACTH-induced changes in 17-OHP secretion.  相似文献   
74.
Lymphocytic choriomeningitis virus (LCMV), strain WE, is a non-cytopathic RNA virus that is highly adapted to its natural host, the mouse. Acute infection of adult mice leads to generalized virus spread, followed by cytotoxic T lymphocyte-mediated virus clearance below the detection levels of conventional assays within 2-3 weeks. Indirect evidence had suggested that virus or viral antigen might persist in the immune mouse. Here we demonstrate LCMV-WE persistence at low levels after infection with 10(2) or 10(6) plaque-forming units, shown as viral genome, viral antigen, and replicative virus using sensitive in vitro and in vivo assays. The finding that LCMV-WE persists in the face of apparently intact immune responses resembles the situation in some viral (hepatitis B and C, HIV) and bacterial (tuberculosis, leprosy) infections in humans; the results are relevant to the understanding not only of other murine and human persistent viral infections but also of protective immunological memory by "infection immunity."  相似文献   
75.
Many different osteotomy procedures has been proposed in the literature for dental implant site preparation. The osseodensification is a drilling technique that has been proposed to improve the local bone quality and implant stability in poor density alveolar ridges. This technique determines an expansion of the implant site by increasing the density of the adjacent bone. The aim of the present investigation was to evaluate the effectiveness of the osseodensification technique for implant site preparation through a literature review and meta-analysis. The database electronic research was performed on PubMed (Medline) database for the screening of the scientific papers. A total of 16 articles have been identified suitable for the review and qualitative analysis—11 clinical studies (eight on animals, three on human subjects), four literature reviews, and one case report. The meta-analysis was performed to compare the bone-to-implant contact % (BIC), bone area fraction occupied % (BAFO), and insertion torque of clockwise and counter-clockwise osseodensification procedure in animal studies. The included articles reported a significant increase in the insertion torque of the implants positioned through the osseodensification protocol compared to the conventional drilling technique. Advantages of this new technique are important above all when the patient has a strong missing and/or low quantity of bone tissue. The data collected until the drafting of this paper detect an improvement when the osseodensification has been adopted if compared to the conventional technique. A significant difference in BIC and insertion torque between the clockwise and counter-clockwise osseodensification procedure was reported, with no difference in BAFO measurements between the two approaches. The effectiveness of the present study demonstrated that the osseodensification drilling protocol is a useful technique to obtain increased implant insertion torque and bone to implant contact (BIC) in vivo. Further randomized clinical studies are required to confirm these pieces of evidence in human studies.  相似文献   
76.
Because of the widespread use of immunosuppressive drugs, CMV infection is one of the most important causes of morbidity and mortality in patients with haematological malignancies worldwide. The aim of the study was to retrospectively analyse the epidemiology of CMV infection in haematological patients. Between 2008 and 2014, 1238 quantitative CMV DNA detections from plasma specimens were performed. These specimens were collected from 271 patients with haematological malignancy. Patients were grouped on the basis of underlying diseases (lymphoid and myeloid malignancies and other haematological diseases). In the lymphoid and myeloid groups, we distinguished ASCT and non-ASCT groups. During the studied period, the majority of examined patients (82.6 %) were treated with lymphoproliferative disease. A total of 126 (46.5 %) patients underwent ASCT, while 145 (53.5 %) did not have stem cell transplantation. A total of 118 (9.5 %) of 1238 plasma specimens proved to be positive for CMV DNA; these specimens were collected from 66 (24.4 %) patients. Twenty-four (16.6 %) of 145 non-ASCT patients had CMV PCR positive specimens. Among non-ASCT patients with positive CMV PCR results, 10 patients were asymptomatic, 14 had symptomatic reactivation, while 2 had CMV disease. In the ASCT group, 42 (33.3 %) patients had CMV PCR positive samples. CMV reactivation was asymptomatic in 34 (81 %) cases, and 8 (19 %) patients had symptomatic reactivation. In the non-ASCT group, the rate of CMV infection is low. In the ASCT group, the prevalence of CMV infection was higher than in the non-ASCT group, but the majority of CMV infection was asymptomatic and only small number of patients had symptomatic reactivation. Thus, our results also showed that the use of routine CMV DNA monitoring is not necessary in patients with haematological malignancies not receiving fludarabine-containing regimen or alemtuzumab, in spite of this to decrease the mortality we have to consider the use of molecular tests in case of suspected infectious conditions.  相似文献   
77.
The aim of this study was to determine if radiotherapy induces hyposalivation altering oral microbial flora. The purpose of this placebo-controlled, single-blind study was to determine beneficial effects of a saliva substitute and an oral hygiene product on irradiated patients with oropharyngeal cancer. Eighteen patients were assigned to the test group (Biotène Oral Balance gel [Lacléde Incorporated Healthcare Products, Gardena, CA] and toothpaste used daily), and another 18 were put on a conventional daily regimen (carboxymethylcellulose gel and Oral-B toothpaste [Laclede Pharmaceuticals, Gardena, CA]). Cultures for identifying and quantitating microorganisms, whole unstimulated saliva, and visual analog measurements for comfort were obtained before mucositis occurred and after treatment. Daily use of Biotène products enhanced control of microbial flora, improved salivary flow, and increased oral comfort as compared with control subjects. Four weeks after mucositis, some aerobic isolates disappeared in the test group; periodontal-associated bacteria were markedly decreased in the test group; and candidal species were significantly lowered in the test group. Although baseline saliva was lower in the test group (P = 0.001), after 4 weeks, no difference between groups existed; comfort was greater in the test group (P = 0.007). Use of enzyme-engineered Biotène products that assist in control of the oral microbial flora as well as supporting oral comfort through lubrication appear to be useful aids for irradiated patients with oropharyngeal cancer.  相似文献   
78.
79.
In this study, we investigated the putative roles of certain protein kinase C (PKC) isoenzymes in the regulation of proliferation and arachidonic acid (AA) release in the human monocytoid MonoMac-6 cell line. Experiments employing specific PKC inhibitors and molecular biological methods (RNA-interference, recombinant overexpression) revealed that the two dominantly expressed isozymes, i.e., the "conventional" cPKCbeta and the "novel" nPKCdelta, promote AA production and cellular proliferation. In addition, using different phospholipase A(2) (PLA(2)) inhibitors, we were able to show that the calcium-independent iPLA(2) as well as diacylglycerol lipase (but not the cytosolic PLA(2)) function as "downstream" targets of cPKCbeta and nPKCdelta. In addition, we have also found that, among the other existing PKC isoforms, cPKCalpha plays a minor inhibitory role, whereas nPKCvarepsilon and aPKCzeta apparently do not regulate these cellular processes. In conclusion, in this paper we provide the first evidence that certain PKC isoforms play pivotal, specific, and (at least partly) antagonistic roles in the regulation of AA production and cellular proliferation of human monocytoid MonoMac-6 cells.  相似文献   
80.
Sipka S  Gyimesi E 《Orvosi hetilap》2007,148(7):299-302
This paper summarizes the most common allergens in Hungary, the various forms of food allergies, the tools of their diagnosis, with special respect to the possibilities of in vitro laboratory tests. These thoughts are in accordance with the position papers of European Academy of Allergology and Clinical Immunology and Hungarian College of Clinical Immunology and Allergology.  相似文献   
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