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131.
Phosphoric acid has been suggested as an irrigant due to its effectiveness in removing the smear layer.

Objectives

: The purpose of this study was to compare the antimicrobial and cytotoxic effects of a 37% phosphoric acid solution to other irrigants commonly used in endodontics.

Material and Methods

: The substances 37% phosphoric acid, 17% EDTA, 10% citric acid, 2% chlorhexidine (solution and gel), and 5.25% NaOCl were evaluated. The antimicrobial activity was tested against Candida albicans, Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Actinomyces meyeri, Parvimonas micra, Porphyromonas gingivalis, and Prevotella nigrescens according to the agar diffusion method. The cytotoxicity of the irrigants was determined by using the MTT assay.

Results

: Phosphoric acid presented higher antimicrobial activity compared to the other tested irrigants. With regard to the cell viability, this solution showed results similar to those with 5.25% NaOCl and 2% chlorhexidine (gel and solution), whereas 17% EDTA and 10% citric acid showed higher cell viability compared to other irrigants.

Conclusion

: Phosphoric acid demonstrated higher antimicrobial activity and cytotoxicity similar to that of 5.25% NaOCl and 2% chlorhexidine (gel and solution).  相似文献   
132.
Delabie  J; Tierens  A; Wu  G; Weisenburger  DD; Chan  WC 《Blood》1994,84(10):3291-3298
Lymphocyte predominance Hodgkin's disease (LPHD) is a clinically indolent condition. Although there is evidence that the putative neoplastic cell in this disease, the "L&H" cell, is of B-cell lineage, there is conflicting data concerning the clonality of these cells. Our study was aimed at clarifying the issue of lineage and clonality of the L&H cells of LPHD using a single-cell assay. Four cases of LPHD were studied. To circumvent the difficulties of obtaining fresh tissue and to be able to study representative cases, a new method was developed to obtain single-cell suspensions of L&H cells from archival formalin- fixed paraffin-embedded tissue. Single L&H cells were identified by morphology and immunostaining for epithelial membrane antigen, isolated using a micropipette, and subjected to polymerase chain reaction (PCR) amplification of the complematarity determining region 3 (CDR3) of the Ig heavy chain (IgH) gene, which is B-cell clone-specific. The PCR products were size-fractionated by polyacrylamide gel electrophoresis and representative products were directly sequenced. Single T cells and small B cells were also isolated from the tissues and used as negative and positive controls, respectively. In all four cases of LPHD, the IgH CDR3 of single L&H cells could be amplified. Within each case, the IgH CDR3 of single L&H cells was found to be of different length or of different sequence. Therefore, our results provide strong evidence for the B-cell origin of the L&H cells and the polyclonal nature of LPHD.  相似文献   
133.
Coagulation factor VIII (FVIII) is a cofactor in the intrinsic pathway of blood coagulation for which deficiency results in the bleeding disorder hemophilia A. FVIII contains a domain structure of A1-A2-B-A3- C1-C2 of which the B domain is dispensable for procoagulant activity in vitro. In this report, we compare the properties of B-domain-deleted FVIII (residues 760 through 1639, designated LA-VIII) to wildtype recombinant FVIII. In transfected Chinese hamster ovary (CHO) cells, LA- VIII was expressed at a 10- to 20-fold greater level compared with wildtype FVIII. The specific activity of purified LA-VIII was indistinguishable from wild-type recombinant FVIII and both exhibited similar thrombin activation coefficients. Wildtype recombinant-derived FVIII and LA-VIII also displayed similar timecourses of thrombin activation and heavy chain cleavage. However, compared with wildtype recombinant-derived FVIII, the light chain of LA-VIII was cleaved fivefold more rapidly by thrombin. Addition of purified von Willebrand factor (vWF) did not alter the kinetics of thrombin cleavage or activation of either wildtype recombinant-derived FVIII or LA-VIII. The immunogenicity of LA-VIII was compared with wildtype FVIII in a novel model of neonatal tolerance induction in mice. The results did not detect any immunologic differences between wildtype FVIII and LA-VIII, suggesting that LA-VIII does not contain significant new epitopes that are absent in wildtype FVIII. LA-VIII was tolerated well on infusion into FVIII-deficient dogs and was able to correct the cuticle bleeding time similar to wildtype recombinant factor VIII. In vivo, LA-VIII was bound to canine vWF and exhibited a half-life similar to wildtype recombinant FVIII. These studies support that B-domain-deleted FVIII may be efficacious in treatment of hemophilia A in humans.  相似文献   
134.
Anti-My-28 is an IgM kappa monoclonal antibody produced by a hybridoma prepared from spleen cells of a mouse immunized with normal human granulocytes. By immunofluorescence it binds to human granulocytes but not to monocytes and lymphocytes. However, after treating cells with neuraminidase, the antibody also binds to lymphocytes and monocytes and to many leukemic cell lines and patient leukemic blast cells. Anti-My- 28 binds to several neutral glycolipids and desialylated gangliosides of leukocytes and erythrocytes as detected by radioimmunoassay and immunostaining of thin-layer chromatograms. It recognizes a sugar sequence in lacto-N-neotetraose, Gal beta 1-4GlcNAc beta 1-3Gal beta 1- 4Glc. This tetrasaccharide occurs in the glycolipids paragloboside and sialosylparagloboside, and its distal trisaccharide sequence is found in higher glycolipids and in glycoproteins.  相似文献   
135.
There is an urgent need to find consensus on screening, diagnosing and treating all degrees of DYSGLYCEMIA that may occur during pregnancies in Brazil, considering that many cases of DYSGLYCEMIA in pregnant women are currently not diagnosed, leading to maternal and fetal complications. For this reason the Brazilian Diabetes Society (SBD) and the Brazilian Federation of Gynecology and Obstetrics Societies (FEBRASGO), got together to introduce this proposal. We present here a joint consensus regarding the standardization of clinical management for pregnant women with any degree of Dysglycemia, on the basis of current information, to improve medical assistance and to avoid related complications of Dysglycemia in pregnancy to the mother and the fetus. This consensus aims to standardize the diagnosis among general practitioners, endocrinologists and obstetricians allowing the dissemination of information in basic health units, public and private services, that are responsible for screening, diagnosing and treating disglycemic pregnant patients.  相似文献   
136.
BackgroundFatty liver disease has reached epidemic proportions in type 2 diabetes. Glucagon-like peptide-1 (GLP-1) analogues are licensed for treatment of type 2 diabetes, yet little data exist on efficacy and safety in liver injury. We aimed to assess the safety and efficacy of 26 weeks' liraglutide on liver function compared with an active placebo.MethodsIndividual patient data meta-analysis was done with patient level data combined from six 26-week, phase 3, double-blind randomised controlled trials on type 2 diabetes, which comprise the Liraglutide Effect and Action in Diabetes (LEAD) programme. In addition, the LEAD-2 sub-study was analysed to assess the effect on CT-measured hepatic steatosis.FindingsOf 4442 patients analysed, 2241 (50·8%) had an abnormal alanine aminotransferase (ALT) at baseline (mean 33·8 IU/L [SD 14·9] in female participants; 47·3 [18·3] in male participants). Liraglutide 1·8 mg reduced ALT in these patients compared with placebo (?8·20 vs ?5·01 IU/L, p=0·003), and was dose dependent (no significant differences vs placebo with liraglutide 0·6 or 1·2 mg). This effect was lost after adjustment for liraglutide's effect on reduction of weight (corrected mean ALT difference vs placebo ?1·41 IU/L, p=0·21) and HbA1c (corrected mean ALT difference vs placebo 0·57 IU/L, p=0·63). Adverse effects with 1·8 mg liraglutide were similar between patients with and without baseline abnormal ALT. In the LEAD-2 sub-study, liraglutide 1·8 mg (26 weeks) improved hepatic steatosis (CT-measured liver:spleen attenuation ratio) from baseline (0·10, p=0·001) and showed a trend towards improvement compared with placebo (0.10 vs 0·00, p=0·07).Interpretation26 weeks of liraglutide (1·8 mg) is safe, well tolerated, and improves liver enzymes compared with placebo in patients with type 2 diabetes.FundingWellcome Trust.  相似文献   
137.
138.
Background/Aims Chronic renal failure (CRF) is often associated with bone disorders including chronic kidney disease–mineral and bone disorder (CKD–MBD). Parathyroid hormone (PTH) has a relationship to bone remodeling, and so this study was undertaken to evaluate changes in bone remodeling markers after parathyroidectomy (PTX). Methods Twelve adult patients, mean age 43.4 ± 12.7 years, of both genders, were evaluated, prior to and six months after PTX. Analysis of biochemical markers of bone metabolism, such as total and ionized calcium, phosphorus, 25(OH)D3, total alkaline phosphatase (TAP), bone-specific alkaline phosphatase (BAP), intact PTH, osteoprotegerin (OPG), and tartrate-resistant acid phosphatase isoform 5b (TRAP), were measured. Results No changes were observed after PTX in the serum total and ionized calcium, TAP, BAP, and 25(OH)D3. After surgery there was a significant decrease in serum phosphorus, iPTH, and TRAP (P < 0.001). No significant change was observed in OPG; however there was a positive correlation between OPG and 25(OH)D3 before and after surgery (r = 0.774, P = 0.014; and r = 0.706, P = 0.01, respectively). The percentage of patients with vitamin D deficiency decreased from 16.7% to 8.3%, while those with sufficient levels increased from 41.7% to 58.3%. Conclusion The small number of patients in the study notwithstanding, the present study is unique because it provides information on bone metabolism and vitamin D status six months after PTX. The removal of parathyroid glands significantly decreased bone resorption and indicated a tendency of 25(OH)D3 concentration to increase. However, the precise role of OPG and BAP in the improvement in bone remodeling in patients with CKD–MBD requires further study.  相似文献   
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