193 resultados para Sun protection factor
Resumo:
Objective: To analyze vascular density and immunolocalization of angiogenic vascular endothelial growth factor (VEGF) and its receptor Flk-1 in the proliferative and secretory eutopic human endometrium. and in three different sites of endometriosis: the ovary, bladder, and rectum. Design: Prospective study. Setting: University hospital. Patient(s): Thirty women with endometriosis (10 ovarian, 1.0 bladder, 10 rectal) and 32 control women (10 proliferative endometrium, 10 secretory endometrium, 4 normal ovary, 4 normal bladder, 4 normal rectum). Intervention(s): Normal endometrial samples were obtained from women during laparoscopic ablation of subserous myoma, and biopsy specimens of endometriosis were obtained from patients undergoing surgery for the diagnosis and treatment of endometriosis. Normal tissues of ovary, bladder, and rectum were obtained from these organs beside the lesions of endometriosis. Main Outcome Measure(S): Blood vessels were quantified according to the number of von Willebrand factor-positive endothelial cells. The VEGF and Flk-1 distribution were evaluated semiquantitatively by immunohistochemical staining. Result(s): More blood vessels were found in cases of endometriosis, particularly rectal endometriosis, compared with the respective control samples and with the eutopic endometrium, and they were localized in endometrial stroma around the glands. The VEGF and Flk-1 expression levels were also higher in cases of endometriosis, especially rectal endometriosis. Conclusion(s): Vascularization and VEGF and Flk-1 expression are significantly higher in deeply infiltrating endometriosis affecting the rectum, reinforcing the hypothesis that antiangiogenesis therapy may constitute a new modality of treatment, especially in cases of deep endometriosis involving the rectum.
Resumo:
Objective: To determine whether there is an association between endometrial expression of leukemia inhibitory factor (LIF) in the luteal phase of the menstrual cycle preceding in vitro fertilization (IVF) and treatment outcome. Methods: Biopsy specimens from the endometria of 52 women in the luteal. phase were immunostained against LIF Embryo culture and transfer were done according to standard procedures. Results: Clinical pregnancy occurred in 39% of the women following IVF, and strong endometrial immunohistochemical staining for LIF was associated with pregnancy (P=0.01). The women with a strong LIF expression had a 6.4-fold higher chance of becoming pregnant than those with weaker intensities (P=0.005). Conclusion: Endometrial expression of LIF during the luteal phase can be used as a predictor of IVF success. (C) 2008 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.
Resumo:
Patients with Gilbert Syndrome have an impaired function of the enzyme UGT1A1, responsible for the degradation of 4-OH-estrogens. These elements are produced by the degradation of estrogens and are well-known carcinogens. In theory, patients with Gilbert Syndrome accumulate 4-OH-estrogens and, therefore, might have a higher risk for breast cancer, especially when exposed to higher levels of estrogens. If this theory is true, a new risk group for breast cancer would be described, producing new insights in breast carcinogenesis. (C) 2011 Elsevier Ltd. All rights reserved.
Resumo:
Arginase activity has been related to leishmaniasis development, thus we studied the constitutive and insulin-like growth factor (IGF) I-induced arginase activity of Leishmania (Viannia) braziliensis isolates from patients with different clinical forms of American tegumentary leishmaniasis (ATL). Isolates from mucosal leishmaniasis presented higher basal levels of arginase activity than isolates from other clinical forms of ATL. Isolates from disseminated leishmaniasis that present mucosal lesion in some cases reached the arginase activity similar to that of isolates from mucosal leishmaniasis upon IGF-I stimulation. Differences in arginase activity may influence disease outcomes such as evolution to mucosal lesion in patients with L (V.) braziliensis infection. (C) 2010 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.
Resumo:
Several studies have suggested an important role for brain-derived neurotrophic factor (BDNF) in the pathophysiology and therapeutics of bipolar disorder (BPD). The mechanisms underlying the therapeutic effects of lithium in BPD seem to involve a direct regulation of neurotrophic cascades. However, no clinical study evaluated the specific effects of lithium on BDNF levels in subjects with BPD. This study aims to investigate the effects of lithium monotherapy on BDNF levels in acute mania. Ten subjects with bipolar I disorder in a manic episode were evaluated at baseline and after 28 days of lithium therapy. Changes in plasma BDNF levels and Young Mania Rating Scale (YMRS) scores were analyzed. A significant increase in plasma BDNF levels was observed after 28 days of therapy with lithium monotherapy (510.9 +/- 127.1 pg/mL) compared to pre-treatment (406.3 +/- 69.5 pg/mL) (p = 0.03). Although it was not found a significant association between BDNF levels and clinical improvement (YMRS), 87% of responders presented an increase in BDNF levels after treatment with lithium. These preliminary data showed lithium`s direct effects on BDNF levels in bipolar mania, suggesting that short-term lithium treatment may activate neurotrophic cascades. Further studies with larger samples and longer period may confirm whether this biological effect is involved in the therapeutic efficacy of lithium in BPD. (C) 2011 Elsevier Ireland Ltd. All rights reserved.
Resumo:
Objectives. The aim of the present study is to investigate serum BDNF levels in older depressed patients as compared to healthy elderly controls. Methods. Twenty-nine elderly subjects with major depression and 42 healthy older adults were enrolled to this study. All depressed patients were antidepressant-free for at least 1 month prior clinical and laboratorial assessments. Serum BDNF levels were determined by sandwich ELISA. Results. BDNF levels were lower in elderly depressed patients as compared to controls (P = 0.034). Patients with late-onset depression had the lowest BDNF level (median 478.5, interquartile range 373.5-740.9 pg/l) when compared to early-onset depression (median 620.7, interquartile range 366.1-971.9 pg/l) and healthy controls (median 711.3, interquartile range 534.7-1181.0 pg/l) (P < 0.03). Conclusions. Reduced serum BDNF level may be a state marker of late-life depression in non-medicated elderly patients. Our findings provide further evidences that reduced neurotrophic support may have an important role in the physiopathology of late-life depression.
Resumo:
BACKGROUND: Among the various occupations which necessarily require long-term and chronic sun exposure is that of a fisherman. However, clinical experience in dermatology earned over several years of medical practice does not seem to confirm this hypothesis. OBJECTIVE: To evaluate clinical, histological and immunological effects of long-term and chronic exposure to ultraviolet radiation in fishermen. METHODS: A prospective, cross-sectional and observational study characterized skin lesions, immunological markers and histological alterations in fishermen, as well as lymphocyte subpopulations compared to a control group. Mann-Whitney, Fisher`s and Wilcoxon statistical tests were used at a significance level of 0.05. RESULTS: There were significant differences between the exposed group and the group protected due to elastosis (p = 0.03), ectasia of dermal vessels (p = 0.012) and number of cells in the epidermal layers between cones (p = 0.029). Most common among fishermen were CD45RO, CD68 + and mastocytes in the skin (p = 0.040, p < 0.001, p = 0.001) and CD3CD8CD45RO in the blood (p = 0.016). CONCLUSION: The alterations suggest that long-term and chronic sun exposure promotes tolerance to ultraviolet radiation, which protects against immunosuppression.
Resumo:
Leptospirosis is a worldwide zoonosis caused by pathogenic Leptospira. The whole-genome sequence of Leptospira interrogans serovar Copenhageni together with bioinformatic tools allow us to search for novel antigen candidates suitable for improved vaccines against leptospirosis. This study focused on three genes encoding conserved hypothetical proteins predicted to be exported to the outer membrane. The genes were amplified by PCR from six predominant pathogenic serovars in Brazil. The genes were cloned and expressed in Escherichia coli strain BL21-SI using the expression vector pDEST17. The recombinant proteins tagged with N-terminal 6xHis were purified by metal-charged chromatography. The proteins were recognized by antibodies present in sera from hamsters that were experimentally infected. Immunization of hamsters followed by challenge with a lethal dose of a virulent strain of Leptospira showed that the recombinant protein rLIC12730 afforded statistically significant protection to animals (44 %), followed by rLIC10494 (40 %) and rLIC12922 (30 %). Immunization with these proteins produced an increase in antibody titres during subsequent boosters, suggesting the involvement of a T-helper 2 response. Although more studies are needed, these data suggest that rLIC12730 and rLIC10494 are promising candidates for a multivalent vaccine for the prevention of leptospirosis.
Resumo:
Toxoplasma gondii is an obligate intracellular parasite that infects a variety of mammals and birds. T. gondii also causes human toxoplasmosis; although toxoplasmosis is generally a benign disease, ocular, congenital or reactivated disease is associated with high numbers of disabled people. Infection occurs orally through the ingestion of meat containing cysts or by the intake of food or water contaminated with oocysts. Although the immune system responds to acute infection and mediates the clearance of tachyzoites, parasite cysts persist for the lifetime of the host in tissues such as the eye, muscle, and CNS. However, T. gondii RH strain tachyzoites irradiated with 255 Gy do not cause residual infection and induce the same immunity as a natural infection. To assess the humoral response in BALB/c and C57BL/6J mice immunized with irradiated tachyzoites either by oral gavage (p.o.) or intraperitoneal (i.p.) injection, we analyzed total and high-affinity IgG and IgA antibodies in the serum. High levels of antigen-specific IgG were detected in the serum of parenterally immunized mice, with lower levels in mice immunized via the oral route. However, most serum antibodies exhibited low affinity for antigen in both mice strain. We also found antigen specific IgA antibodies in the stools of the mice, especially in orally immunized BALB/c mice. Examination of bone marrow and spleen cells demonstrated that both groups of immunized mice clearly produced specific lgG, at levels comparable to chronic infection, suggesting the generation of IgG specific memory. Next, we challenged i.p. or p.o. immunized mice with cysts from ME49. VEG or P strains of T. gondii. Oral immunization resulted in partial protection as compared to challenged naive mice: these findings were more evident in highly pathogenic ME49 strain challenge. Additionally, we found that while mucosal IgA was important for protection against infection, antigen-specific IgG antibodies were involved with protection against disease and disease pathogenesis. Most antigen responsive cells in culture produced specific high-affinity IgG after immunization, diverse of the findings in serum IgG or from cells after infection, which produced low proportion of high-avidity IgG. (C) 2011 Elsevier B.V. All rights reserved.
Resumo:
Background: Steroidogenic factor 1 (SF-1) is a key determinant of endocrine development and function of adrenal cortex. SF-1 overexpression and gene amplification were previously demonstrated in a small group of pediatric adrenocortical tumors. Objective: Our objective was to determine the frequency of SF-1 protein expression and gene amplification in a large cohort of pediatric and adult adrenocortical tumors. Patients: SF-1 protein expression was assessed in a cohort of 103 adrenocortical tumors from 36 children and 67 adults, whereas gene amplification was studied in 38 adrenocortical tumors ( 17 from children). Methods: Tissue microarray, multiplex ligation-dependent probe amplification, and quantitative real-time PCR were used. Results: Astrong nuclear SF-1 expression was detected by tissue microarray in 56% (20 of 36) and 19% (13 of 67) of the pediatric and adult adrenocortical tumors, respectively (P = 0.0004). Increased SF-1 copy number was identified in 47% (eight of 17) and 10% (two of 21) of the pediatric and adult adrenocortical tumors, respectively (P = 0.02). All adrenocortical tumors with SF-1 gene amplification showed a strong SF-1 staining, whereas most of the tumors (61%) without SF-1 amplification displayed a weak or negative staining (P = 0.0008). Interestingly, a strong SF-1 staining was identified in five (29%) pediatric adrenocortical tumors without SF-1 amplification. The frequency of SF-1 overexpression and gene amplification was similar in adrenocortical adenomas and carcinomas. Conclusion: We demonstrated a higher frequency of SF-1 overexpression and gene amplification in pediatric than in adult adrenocortical tumors, suggesting an important role of SF-1 in pediatric adrenocortical tumorigenesis. (J Clin Endocrinol Metab 95: 1458-1462, 2010)
Resumo:
Dendritic cells belong to a family of antigen-presenting cells that are localized at the entry sites, such as skin and mucosa. Dendritic cells are related to immune surveillance function. The role of Langerhans cells in the pathogenesis of skin infectious diseases is well studied; however, there are few articles addressing involvement of factor XIIIa-positive dermal dendrocytes (FXIIIa+ DD) in such processes. FXIIIa+ DDs are bone marrow-monocytic lineage-derived cells and members of the skin immune system. Due to their immune phenotype and functional characteristics, they are considered complementary cells to Langerhans cells in the process of antigen presentation and inducing immune response. To verify the interaction between FXIIIa+ DD and Leishmania amastigotes, 22 biopsies of American tegumentary leishmaniasis (ATL) skin lesions were subjected to double staining technique with anti-factor XIIIa and anti-Leishmania antibodies. FXIIIa+ DDs were hypertrophic and abundant in the cutaneous reaction of ATL. FXIIIa+ DDs harboring parasites were observed in I I of 22 skin biopsies. The data obtained suggest that FXIIIa+ DD plays a role in the pathogenesis of ATL skin lesion as host cell, immune effector, and/or antigen-presenting cell.
Resumo:
Leprosy is a curable chronic granulomatous infectious disease caused by the bacillus Mycobacterium leprae. This organism has a high affinity for skin and peripheral nerve cells. In the evolution of infections, the immune status of patients determines the disease expression. Dendritic cells are antigen-presenting cells that phagocytose particles and microorganisms. In skin, dendritic cells are represented by epidermal Langerhans cells and dermal dendrocytes, which can be identified by expression of CD1a and factor XIIIa (FXIIIa). In the present study, 29 skin samples from patients with tuberculoid (13 biopsies) and lepromatous (16 biopsies) leprosy were analyzed by immunohistochemistry using antibodies to CD1a and FXIIIa. Quantitative analysis of labeling pattern showed a clear predominance of dendritic cells in tuberculoid leprosy. Difference between the number of positive cells of immunohistochemistry for the CD1a and FXIIIa staining observed in this study indicates a role for dendritic cells in the cutaneous response to leprosy. Dendritic cells may be a determinant of the course and clinical expression of the disease.
Resumo:
Context: Although numerous studies have examined the role of latent variables in the structure of comorbidity among mental disorders, none has examined their role in the development of comorbidity. Objective: To study the role of latent variables in the development of comorbidity among 18 lifetime DSM-IV disorders in the World Health Organization World Mental Health Surveys. Design: Nationally or regionally representative community surveys. Setting: Fourteen countries. Participants: A total of 21 229 survey respondents. Main Outcome Measures: First onset of 18 lifetime DSM-IV anxiety, mood, behavior, and substance disorders assessed retrospectively in the World Health Organization Composite International Diagnostic Interview. Results: Separate internalizing (anxiety and mood disorders) and externalizing (behavior and substance disorders) factors were found in exploratory factor analysis of lifetime disorders. Consistently significant positive time-lagged associations were found in survival analyses for virtually all temporally primary lifetime disorders predicting subsequent onset of other disorders. Within-domain (ie, internalizing or externalizing) associations were generally stronger than between-domain associations. Most time-lagged associations were explained by a model that assumed the existence of mediating latent internalizing and externalizing variables. Specific phobia and obsessive-compulsive disorder (internalizing) and hyperactivity and oppositional defiant disorders (externalizing) were the most important predictors. A small number of residual associations remained significant after controlling the latent variables. Conclusions: The good fit of the latent variable model suggests that common causal pathways account for most of the comorbidity among the disorders considered herein. These common pathways should be the focus of future research on the development of comorbidity, although several important pairwise associations that cannot be accounted for by latent variables also exist that warrant further focused study.
Resumo:
Background & aims: Hypovitaminosis D [serum 25 vitamin D < 30 ng/ml] is related to the development of metabolic bone disease and greater risk of chronic illnesses. However, it is frequently under-diagnosed, mainly in countries where UV radiation is abundant. We prospectively determined the prevalence and the predictors of serum 25 vitamin D (s25(OH)D) in a healthy Brazilian population after the winter and after the summer. Methods: 603 (118M and 485F) healthy Brazilian volunteers aged 18-90 years from a universitary hospital were selected after the winter of 2006. From the initial sample, 209 volunteers (31M and 178F) accepted to participate in a second health check after the subsequent summer. Results: After the winter, median s25(OH)D was 21.4 ng/mL and 77.4% of the population presented hypovitaminosis D. s25(OH)D was significantly related to age, BMI, PTH and race. In multivariate linear regression analysis, s25(OH)D was significantly and independently dependent on age, glycemia and skin color. Significant increase in s25(OH)D was verified after summer [10.6 (3.7-19.3 ng/ml); p < 0.001] and this improvement was dependent on age. We also observed a significant decrease in hyperparathyroidism prevalence (20.8% vs. 4.9%; P < 0.0001). Conclusion: In Sao Paulo, at the end of winter, we observed a high prevalence of hypovitaminosis D and secondary hyperparathyroidism in healthy adults. s25(OH)D was dependent on age and skin color. After summer, we observed a decrease in the prevalence of hypovitaminosis D. This unexpected finding emphasizes the need for a strong recommendation to monitor s25(OH)D, even in a sunny country such as Brazil. (C) 2010 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
Resumo:
Brain-derived neurotrophic factor (BDNF) is the most widely distributed neurotrophin in the CNS, where it plays several pivotal roles in synaptic plasticity and neuronal survival. As a consequence, BDNF has become a key target in the physiopathology of several neurological and psychiatric diseases. Recent studies have consistently reported altered levels of BDNF in the circulation (i.e., serum or plasma) of patients with major depression, bipolar disorder, Alzheimer`s disease, Huntington`s disease and Parkinson`s disease. Correlations between serum BDNF levels and affective, cognitive and motor symptoms have also been described. BDNF appears to be an unspecific biomarker of neuropsychiatric disorders characterized by neurodegenerative changes.