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991.
Purpose: The purpose of the present study was to determine whether contact lens wear disturbed the levels of tear proteins and to further determine whether this was a transient or continuous disruption. Methods: Lactoferrin, lysozyme and albumin were quanti-tated from tears of neophyte patients and were compared with the levels of these proteins in contact lens wearers after one and six nights and 6 months of extended wear The quantitation of these tear proteins was performed by sandwich ELISA and turbidimetric assay. Results: Results showed that there were no statistically significant changes in the concentration of any of the proteins investigated. Conclusions: Extended wear of hydrogel lenses does not appear to alter the concentration of the major tear film proteins, indicating that the tear film is constantly replenished to maintain protein levels, which are depleted due to protein adsorption to the lens surface. 相似文献
992.
M. Gonçalo A. Figueiredo P. Tavares C. A. Fontes Ribeiro F. Teixeira A. Polares Baptista 《Contact dermatitis》1992,27(5):287-290
We studied 2 groups of patients. One group of 10 patients had a photosensitive eruption to piroxicam. Another group of 24 patients had positive patch test reactions to thimerosal and thiosalicylic acid and had never taken piroxicam or tenoxicam. Patients were patch tested with thimerosal 0.1% pet., thiosalicylic acid 0.1% pet., salicylic acid 2.0% pet., piroxicam 1 and 5% pet. and tenoxicam 1 and 5% pet. Photopatch tests were also performed with piroxicam and tenoxicam. All 10 patients with photosensitivity to piroxicam had positive patch tests to thimerosal and thiosalicylic acid and 9 of them had positive photopatch tests to piroxicam. 20 out of 24 patients with positive patch tests to thiosalicylic acid also had positive photopatch tests to piroxicam. All the patients tested with salicyclic acid were negative. Out of the 29 patients with positive photopatch tests to piroxicam, none reacted to tenoxicam. In countries with a high incidence of contact sensitivity to thimerosal/thiosalicylic acid, the use of piroxicam should be avoided and replaced by tenoxicam, a drug without reported photosensitivity. 相似文献
993.
Granulocyte colony-stimulating factor (G-CSF) production and G-CSF receptor structure in patients with congenital neutropenia 总被引:5,自引:1,他引:5
Congenital neutropenia (Kostmann's syndrome [KS]) is an autosomal recessive syndrome that is characterized by profound neutropenia, resulting in major clinical infections and death. Since the neutropenia and symptoms in KS improve in response to exogenous administration of granulocyte colony-stimulating factor (G-CSF), we studied bone marrow cytokine (G-CSF, granulocyte-macrophage CSF [GM-CSF], and interleukin- 6) production under both basal and stimulated conditions. No differences in G-CSF, GM-CSF, or IL-6 gene expression were found in bone marrow stromal cells between normal controls and KS patients, and all three cytokines were detected by enzyme-linked immunosorbent assay (ELISA) in medium conditioned by bone marrow stromal cells from normal donors and patients with KS. Each KS patient tested had detectable, functional G-CSF in their own serum before exogenous G-CSF administration. Since G-CSF production appeared normal in KS patients, we then asked whether we could detect structural defects in the signaling portion of G-CSF receptor genes. Polymerase chain reaction (PCR) amplification of the G-CSF receptor transmembrane region alone, and of the transmembrane plus cytosolic portions of the receptor, yielded the size products predicted from the sequences of the normal G- CSF receptor. Single-strand conformational polymorphism (SSCP) analysis of G-CSF receptor PCR products demonstrated no variance in structural conformation between KS patients and normal subjects. These results demonstrate that bone marrow stromal cells in patients with KS secrete normal concentrations of functional G-CSF and suggest that the neutropenia in KS patients is caused by an inability of neutrophilic progenitor and precursor cells to respond to normal, physiologic levels of G-CSF. Such a defect, clinically responsive to pharmacologic doses of G-CSF, might be caused by defects in the post-G-CSF receptor signal transduction pathway. 相似文献
994.
Santa-Clara H Fernhall B Baptista F Mendes M Bettencourt Sardinha L 《Metabolism: clinical and experimental》2003,52(11):1413-1417
Increased fat mass, particularly abdominal fat mass, is associated with poor metabolic profiles and an increase in cardiovascular risk factors. The purpose of this study was to evaluate the effect of a 1-year combined aerobic and strength training regimen, compared to aerobic training only, on body composition in patients with coronary artery disease (CAD). Thirty-six males with CAD were assigned to 3 groups: 13 to weight training plus aerobic training (combined training group [CT]), 13 to aerobic training only (aerobic training group [AT]), and 10 to a control group (no exercise [CG]). Body composition was determined by dual-energy x-ray absorptiometry (DEXA). Differences were observed between groups at the end of the study, controlling for prevalues. The total and trunk percent fat mass (%FM) were lower in CT compared with AT and CG (P<.05). The total %FM in AT was significantly (P<.05) lower than in CG, but the %FM of the trunk did not differ between the 2 groups. Fat-free mass (FFM) was significantly higher in CT than in AT and CG (P<.05). The results suggest that a long-term CT program is more effective than an AT program alone in producing changes in body composition. The percentage changes in total and trunk fat mass were higher in CT (-11% and -12%, respectively) than in AT (-2.4% and -0.7%, respectively). Future studies need to investigate the specific health effects of trunkal fat mass loss in patients with CAD. 相似文献
995.
In vivo photodynamic inactivation of Candida albicans using chloro‐aluminum phthalocyanine
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JC Carmello F Alves APD Ribeiro FG Basso CA de Souza Costa AC Tedesco FL Primo EG Mima AC Pavarina 《Oral diseases》2016,22(5):415-422
This study evaluated the photoinactivation of Candida albicans in a murine model of oral candidiasis using chloro‐aluminum phthalocyanine (ClAlP) encapsulated in cationic nanoemulsions (NE) and chloro‐aluminum phthalocyanine (ClAlP) diluted in DMSO (DMSO) as photosensitizer (PS). Seventy‐five 6‐week‐old female Swiss mice were immunosuppressed and inoculated with C. albicans to induce oral candidiasis. PDT was performed on the tongue by the application of the photosensitizers and LED light (100 J cm?2–660 nm). Twenty‐four hours and 7 days after treatments, microbiological evaluation was carried out by recovering C. albicans from the tongue of animals (CFU ml?1). Then, mice were sacrificed and the tongues were surgically removed for histological and biomolecular analysis of pro‐ and anti‐inflammatory cytokines. Data were analyzed by ANOVA followed by Tukey's post hoc test. ClAlP‐NE‐mediated PDT reduced 2.26 log10 of C. albicans recovered from the tongue when compared with the control group (P?L?) (P < 0.05). PDT did not promote adverse effects on the tongue tissue. Seven days after treatment, all animals were completely healthy. In summary, PDT mediated by chloro‐aluminum phthalocyanine entrapped in cationic nanoemulsions was effective in reducing C. albicans recovered from the oral lesions of immunocompromised mice. 相似文献
996.
Cortez-Pinto H Baptista A Camilo ME De Moura MC 《Digestive diseases and sciences》2003,48(10):1909-1913
A previous publication analyzed the clinicopathological characteristics of 105 patients with steatohepatitis: 32 nonalcoholic, 21 ambulatory alcoholics, and 52 hospitalized alcoholics; we now report an up to 12-year follow-up (mean 5.9 ± 4.7). Between 1988 and 1993, all patients with a histological diagnosis of steatohepatitis were included; necrosis, inflammation, Mallory bodies, and fibrosis were graded. Complete follow-up data were obtained in 78%. Survival curves were similar between nonalcoholic and ambulatory alcoholics; they were, however, better in nonalcoholic than hospitalized alcoholics (P < 0.0001), and in ambulatory relative to hospitalized (P = 0.0001) alcoholics. Nonalcoholics had a better prognosis than the combined alcoholic groups (P = 0.001). Patients with moderate to severe Mallory bodies and severe fibrosis had a significantly worse survival (P < 0.01), whereas severity of hepatocellular damage and neutrophil or mononuclear infiltration had no significant impact. In conclusion, alcoholic patients as a whole had a worse prognosis, yet the ambulatory subgroup had a prognosis similar to nonalcoholic patients. 相似文献
997.
Joana Maria Ribeiro Pedro A. Sousa Natália António Rui Baptista Luís Elvas Sérgio Barra Lino Gonçalves 《Revista portuguesa de cardiologia》2021,40(6):437-444
Introduction and AimsCatheter ablation has been shown to improve left ventricular (LV) ejection fraction (LVEF) in patients with atrial fibrillation (AF) and heart failure (HF). Our aim was to assess the impact of AF ablation on the outcome of patients with HF and LV systolic dysfunction.MethodsWe performed a retrospective observational cohort study of all patients with HF and LVEF <50% and with no apparent cause for systolic dysfunction other than AF who underwent catheter ablation in a tertiary referral center between July 2016 and November 2018. The primary endpoint was a ≥5% improvement in LVEF. Secondary endpoints included improvement in New York Heart Association (NYHA) class and reduction in LV end-diastolic diameter (LVEDD) and left atrial diameter (LAD).ResultsOf 153 patients who underwent AF ablation in this period, 22 (77% male, median age 61 [IQR 54-64] years) fulfilled the inclusion criteria. Median follow-up was 11.1 months (IQR 6.1-19.0). After ablation, median LVEF increased from 40% (IQR 33-41) to 58% (IQR 55-62) (p<0.01), mean NYHA class improved from 2.35±0.49 to 1.3±0.47 (p<0.001), and median LAD and LVEDD decreased from 48.0 (IQR 43.5-51.5) mm to 44 (IQR 40-49) mm (p<0.01) and from 61.0 (IQR 54.0-64.8) mm to 55.0 (52.2-58.0) mm (p<0.01), respectively.ConclusionIn patients with HF and LV systolic dysfunction, AF ablation is associated not only with improved functional status but also with favorable structural remodeling, including improvement in LVEF and decreases in LAD and LVEDD. 相似文献
998.
A randomized trial of leukocyte-depleted platelet transfusion to modify alloimmunization in patients with leukemia 总被引:1,自引:2,他引:1
In an effort to determine whether the use of leukocyte (WBC) depleted platelets could modify the development of alloimmunization, 98 adult patients with acute nonlymphocytic leukemia receiving initial induction therapy were randomized to receive standard pooled platelet concentrates (PC) or WBC-depleted PC. WBC depletion was produced by an additional centrifugation of pooled PC, with removal of 81% of WBC and an associated platelet loss of 27%. Lymphocytotoxic antibody (LCTAb) levels were monitored as a serologic marker of alloimmunization. Overall, 5 of 25 evaluable patients receiving WBC-depleted PC developed LCTAb, compared to 13/31 receiving standard PC (p = 0.071). There was no significant difference in alloimmunization rate in the subgroup of patients who had no previous exposure to histocompatibility antigens by pregnancy or prior transfusions (4/15 alloimmunized receiving WBC depleted versus 4/12 receiving standard PC). There was no difference in the number of patients in each group who required HLA-matched platelets during induction therapy. In view of the significant loss of platelets with WBC depletion, the expense and difficulty of providing WBC-poor RBC, the absence of impact on the need for HLA-matched platelets during induction, and the small potential benefit from this approach, WBC- depleted platelets should not be utilized to prevent alloimmunization in patients with leukemia. 相似文献
999.
Interleukin 2-activated killer cells in patients following transplants of soybean lectin-separated and E rosette-depleted bone marrow 总被引:1,自引:2,他引:1
Keever CA; Welte K; Small T; Levick J; Sullivan M; Hauch M; Evans RL; O'Reilly RJ 《Blood》1987,70(6):1893-1903
During the early period following bone marrow transplantation before the immune system has reached full functional maturity, unprimed, nonspecific lytic systems may play a critical role as antiviral or antitumor effectors. The reconstitution of cells with this potential is of particular importance in recipients of bone marrow that has been depleted of mature T lymphocytes to prevent graft v host disease (GVHD). We examined the recovery of natural killer (NK) cells and interleukin 2 (IL 2)-augmented lymphokine-activated killer cells (LAK) in 48 patients at various intervals following transplantation of bone marrow depleted of mature cellular elements by treatment with soybean agglutinin and sheep RBCs (SBA-E- BMT). We found normal levels of both NK and LAK activity as early as 3 weeks following SBA-E- BMT. When compared with cells from controls, NK and LAK precursors from transplant recipients appeared to be activated in vivo in that freshly isolated peripheral blood mononuclear cells (PBMCs) from patients had an elevated cytolytic activity toward NK-insensitive targets and a more rapid response to activation by IL 2. In patients as well as controls, both LAK precursors and LAK effectors lacked antigens present on mature T lymphocytes (CD3, CD4, or CD8) but expressed antigens present on NK cells (CD2, CD16, and NKH1A). The LAK cells did not lyse either donor or host peripheral blood T cell targets. The activity of NK effectors but not LAK precursors survived the in vivo total body irradiation used for pretransplant conditioning in three patients studied. LAK precursors could be demonstrated as early as 18 days following transplant at a time when the bone marrow contained primarily donor- derived cells. Little or no LAK activity could be generated from cells of the SBA-E- BM graft itself, suggesting that LAK precursors differentiate rapidly from more primitive progenitors in the marrow graft. Thus, our data indicate that the NK and LAK lytic systems are among the earliest activities to recover during immune reconstitution following T cell-depleted BMTs. 相似文献
1000.
Purpose To present subtotal splenectomy and splenorenal shunt as a surgical option to treat severe bleeding from a Roux en Y jejunal
loop varices secondary to portal hypertension.
Method A 64-year-old white woman presented severe episodes of bleeding from varices inside a Roux en Y jejunal loop secondary to
portal hypertension due to cirrhosis. Subtotal splenectomy was performed with preservation of the upper splenic pole supplied
by the splenogastric vessels. This procedure was combined with a central splenorenal shunt to divert part of portal blood
to systemic flow.
Results This procedure was safely performed with no complications. A 2-year post-operative follow-up of the patient has been uneventful.
No re-bleeding occurred during this period and she returned to her normal life.
Conclusion Subtotal splenectomy combined with central splenorenal shunt seems to be a safe procedure useful for the treatment of enteral
bleedings due to portal hypertension. 相似文献