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31.
BACKGROUND: Cytomegalovirus (CMV) infection or reactivation is a frequent complication of renal transplantation. Diagnosis of these conditions relies on the detection of circulating antigen, or of specific IgM and/or IgG, which develop over several weeks. Evocative clinical features may be detected earlier, but lack specificity. Rapid and early changes in the partition of lymphocyte subsets could be an additional indication of pending CMV infection. METHODS: A systematic follow-up of peripheral B lymphocytes identified immunophenotypically by the determination of surface immunoglobulins (sIg), performed in 97 kidney transplant recipients, allowed to identify transient increases apparently predictive of CMV primo-infection or reactivation over the next 3 months. To better define the nature of these B cells, an extended investigation was performed for 14 prospective patients. In addition to surface Ig, membrane CD19, HLA-DR, and CD80 expression were explored. The cytoplasmic presence of mu, kappa, and lambda chains was also examined. B cell function was investigated using the ELISPOT technique, which allows an enumeration of the populations of IgG, IgA, and IgM secreting B cells. RESULTS: Retrospective analysis of the clinical outcome of the cohort of 97 patients evidenced that early transient increases in B cell levels were significantly (P<0.0001) associated with CMV infection. The same trend was noted in the smaller series of patients who benefited from a more extensive investigation of B cells, 10 of whom presented clinical or biological signs of CMV infection. Mature B cells, expressing surface Ig, CD19, DR, and CD80 are those presenting transient increases. No significant variation of preB (cmu+/kappalambda-) or activated (spot-forming) cells was evidenced in these patients. CONCLUSION: Individual examination of each patient's immune reconstitution profile allows to detect transient peaks of mature B cell during the initial immunosuppressive therapy, that appear to be predictive of oncoming CMV infection or reactivation.  相似文献   
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An animal model of lung carcinogenicity induced by chronic inhalation of mainstream cigarette smoke would be useful for research on carcinogenic mechanisms, smoke composition-response relationships, co-carcinogenicity, and chemoprevention. A study was conducted to determine if chronic whole-body exposures of rats would significantly increase lung tumor incidence. Male and female F344 rats (n = 81 to 178/gender) were exposed whole-body 6 h/day, 5 days/week for up to 30 months to smoke from 1R3 research cigarettes diluted to 100 (LS) or 250 (HS) mg total particulate matter/m(3), or sham-exposed to clean air (C). Gross respiratory tract lesions and standard lung and nasal sections were evaluated by light microscopy. A slight reduction of survival suggested that the HS level was at the maximum tolerated dose as commonly defined. Cigarette smoke exposure significantly increased the incidences of non-neoplastic and neoplastic proliferative lung lesions in females, while nonsignificant increases were observed in males. The combined incidence of bronchioloalveolar adenomas and carcinomas in females were: HS = 14%; LS = 6%; and C = 0%. These incidences represented minima because only standard lung sections and gross lesions were evaluated. Mutations in codon 12 of the K-ras gene occurred in 4 of 23 (17%) tumors. Three mutations were G to A transitions and one was a G to T transversion. The incidence of neoplasia of the nasal cavity was significantly increased at the HS, but not the LS level in both males and females (HS = 6%, LS = 0.3%, C = 0.4% for combined genders). These results demonstrate that chronic whole-body exposure of rats to cigarette smoke can induce lung cancer.  相似文献   
33.
An ever-increasing number of persons seek medical solutions to improve the appearance of their aging skin or for aesthetic and cosmetic indications in diverse pathological conditions, such as malformations, trauma, cancer, and orthopedic, urological, or ophthalmological conditions. Currently, physicians have many different types of dermal and subdermal fillers, such as non-permanent, permanent, reversible, or non-reversible materials. Despite the claims of manufacturers and different authors that fillers are non-toxic and non-immunogenic or that complications are very uncommon, unwanted side effects do occur with all compounds used. Implanted, injected, and blood-contact biomaterials trigger a wide variety of adverse reactions, including inflammation, thrombosis, and excessive fibrosis. Usually, these adverse reactions are associated with the accumulation of large numbers of mononuclear cells. The adverse reactions related to fillers comprise a broad range of manifestations, which may appear early or late and range from local to systemic. Clinicians should be aware of them since the patient often denies the antecedent of injection or is unaware of the material employed. Most of these adverse effects seem to have an immunological basis, the fillers acting more as adjuvants than as direct T-cell activators, on a background of genetic predisposition. Their treatment has not been the subject of well-designed studies; management of both acute and systemic reactions is often difficult, and requires anti-inflammatory and occasionally immunosuppressive therapy. The clinical, pathological, and therapeutic aspects of inflammatory and immune-mediated late-onset adverse reactions related to soft tissue filler injections are thoroughly reviewed herein.  相似文献   
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Human exposure to and contamination by environmental toxic compounds generates discourses and practices that merit greater attention. In this article, we assess internal chemical contamination and the risk of toxic effects as an experience related to the production of meaning in everyday life. Drawing on the analysis of semantic networks of narratives from semi-structured interviews conducted with 43 informants in Catalonia, Spain, we consider participants’ perceptions of the health risks of toxic compounds, including social discourses on exposure, toxicity, and internal chemical contamination, and on responsibilities, consequences, and proposed strategies for controlling toxic compounds. Informants’ narratives on the relationships between nature and nurture suggest that they no longer perceive rigid boundaries separating the human body from the external environment and its chemical pollutants.  相似文献   
36.
Patients with severe mental illness have higher prevalences of cardiovascular risk factors (CRF). The objective is to determine whether interventions to modify lifestyles in these patients reduce anthropometric and analytical parameters related to CRF in comparison to routine clinical practice. Systematic review of controlled clinical trials with lifestyle intervention in Medline, Cochrane Library, Embase, PsycINFO and CINALH. Change in body mass index, waist circumference, cholesterol, triglycerides and blood sugar. Meta-analyses were performed using random effects models to estimate the weighted mean difference. Heterogeneity was determined using i2 statistical and subgroups analyses. 26 studies were selected. Lifestyle interventions decrease anthropometric and analytical parameters at 3 months follow up. At 6 and 12 months, the differences between the intervention and control groups were maintained, although with less precision. More studies with larger samples and long-term follow-up are needed.  相似文献   
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1. Laboratory experiments were carried out to assess uptake and metabolism of the epilepsy drug, carbamazepine and its consequent biological responses in marine clam (Ruditapes decussatus) a model non-target organism in ecotoxicology.

2. Clams were exposed to two nominal concentrations (C1?=?30?μg/L and C2?=?50?μg/L) of CBZ for a maximum period of 14 days. Analysis of CBZ and their metabolites in clam and water after exposure to two nominal concentrations of the pharmaceutical drug were performed using UPLC-HRMS analysis. CBZ accumulation reached an average tissue concentration of 1241.59 ng/g dw and 1664.33 ng/g dw at low and high nominal concentration, respectively.

3. Furthermore, a metabolite (3-hydroxy-CBZ) was detected in tissues indicating carbamazepine translocation and metabolism inside clam, suspect screening of CBZ glucuronides was also performed by accurate mass extraction but it could not be detected.

4. Activities of antioxidant enzymes superoxide dismutase, catalase and gluthatione-S-transferase generally increased. Change in the contents of glutathione, malondialdehyde and protein carbonyl were also studied.

5. Results indicated that the bioaccumulation of CBZ resulted in the changes of the antioxidant defense system and the production of ROS with the oxidative stress, ultimately induced alteration in lipid peroxidation and protein carbonyl.  相似文献   
40.
ObjetivoEl objetivo del estudio es describir la percepción de la calidad de vida relacionada con la salud de personas con depresión y comorbilidad física bajo una perspectiva de género. Se incluyeron 380 individuos mayores de 49 años con, al menos, una patología de las siguientes: diabetes, enfermedad obstructiva pulmonar crónica y cardiopatía isquémica, reclutadas en 31 equipos de atención primaria de Cataluña. La calidad de vida se midió con la escala EuroQol (EQ-5D). Además, se recogieron variables sociodemográficas, gravedad de depresión, índice de privación económica y ámbito de residencia. Se evaluó la relación ajustada entre el sexo y las dimensiones de calidad de vida, mediante una regresión logística multivariante.ResultadosEl 81,3% fueron mujeres; la media de edad fue de 68,4 años (DE: 8,8), La media de la escala visual analógica fue de 57,8 (DE: 17,4) en hombres y 55,8 (DE: 18,6) en mujeres. La media del EQ-Health Index fue de 0,74 (DE: 0,17) en hombres y 0,65 (DE: 0,21) en mujeres (p = 0,001). La probabilidad de presentar problemas en las dimensiones del EQ-5D mostró el sexo como factor de más peso (mujer = 1/hombre = 0) en: autocuidado OR: 2,29 (IC 95% 1,04 a 5,07) y actividades cotidianas OR: 3,09 (IC 95% 1,67 a 5,71). La movilidad se asoció con la edad OR: 1,87 (IC 95% 1,22 a 2,86), el ámbito de residencia con el dolor OR: 2,51 (IC 95% 1,18 a 5,34) y el Beck Depression Inventory (BDI) con la ansiedad/depresión OR: 4,77 (IC 95% 1,77 a 12,88).ConclusiónLa percepción en la calidad de vida de las mujeres con depresión y comorbilidad física es inferior a la de los hombres, siendo en ambos casos inferior a la de población general.Palabras clave: Calidad de vida, Depresión, Comorbilidad física, Género, Atención Primaria  相似文献   
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