84 resultados para positive semi-definite matrices


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Background: Few studies have addressed small airway (SA) histopathological changes and their possible role in the remodeling process in idiopathic interstitial pneumonias. Objectives: To study morphological, morphometrical and immunohistochemical features of SA in idiopathic pulmonary fibrosis (usual interstitial pneumonia, UIP) and nonspecific interstitial pneumonia (NSIP). Methods: We analyzed SA pathology in lung biopsies from 29 patients with UIP and 8 with NSIP. Biopsies were compared with lung tissue from 13 patients with constrictive bronchiolitis (CB) as positive controls and 10 normal autopsied control lungs. We semi-quantitatively analyzed SA structure, inflammation, architectural features and the bronchiolar epithelial immunohistochemical expression of TGF-beta, MMP-2, 7, 9, and their tissue inhibitors (TIMP-1, 2). Results: Compared to controls, patients with UIP, NSIP and CB presented increased bronchiolar inflammation, peribronchiolar inflammation and fibrosis and decreased luminal areas. UIP patients had thicker walls due to an increase in most airway compartments. NSIP patients presented increased epithelial areas, whereas patients with CB had larger inner wall areas. All of the groups studied presented increased bronchiolar expression of MMP-7 and MMP-9, compared to the controls. Conclusion: We conclude that SAs are pathologically altered and may take part in the lung-remodeling process in idiopathic interstitial pneumonias. Copyright (C) 2009 S. Karger AG, Basel

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Obstructive sleep apnea and hypertension are common conditions that frequently coexist. Continuous positive airway pressure (CPAP) reduces blood pressure in patients with obstructive sleep apnea and sustained hypertension. However, the impact of CPAP on patients with obstructive sleep apnea and prehypertension and masked hypertension, conditions associated with increased cardiovascular risk, is unknown. Thirty-six male patients (age, 43 +/- 7 years; body mass index, 28.8 +/- 3.0 kg/m(2)) with untreated severe obstructive sleep apnea (apnea-hypopnea index, 56 +/- 22 events/hr on polysomnography) with diagnostic criteria for prehypertension and/or masked hypertension, based on office and 24-hour ambulatory blood pressure monitoring, respectively, were studied. The patients randomized to no treatment (control; n=18) or CPAP (n=18) for 3 months had similar frequency of prehypertension and masked hypertension at study entry. There were no significant changes in blood pressure in patients randomized to the control group. In contrast, patients randomized to CPAP presented significant reduction in office systolic (from 126 +/- 5 to 121 +/- 7 mm Hg; P=0.001) and a trend for diastolic blood pressure (from 75 +/- 7 to 73 +/- 8 mm Hg; P=0.08) as well as a significant decrease in daytime and nighttime systolic and diastolic blood pressure (P < 0.05 for each comparison). There was a significant reduction in the frequency of prehypertension (from 94% to 55%; P=0.02) and masked hypertension (from 39% to 5%; P=0.04) only in the CPAP group. In conclusion, effective CPAP therapy promotes significant reduction in the frequency of prehypertension and masked hypertension by promoting significant blood pressure reductions in patients with severe obstructive sleep apnea. (Hypertension. 2011;57[part 2]:549-555.)

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Background: To evaluate the cardiopulmonary effects of positive end-expiratory pressure (PEEP) equalization to intra-abdominal pressure (IAP) in an experimental model of intra-abdominal hypertension (IAH) and acute lung injury (ALI). Methods: Eight anesthetized pigs were submitted to IAH of 20 mm Hg with a carbon dioxide insufflator for 30 minutes and then submitted to lung lavage with saline and Tween (2.5%). Pressure x volume curves of the respiratory system were performed by a low flow method during IAH and ALI, and PEEP was subsequently adjusted to 27 cm center dot H(2)O for 30 minutes. Results: IAH decreases pulmonary and respiratory system static compliances and increases airway resistance, alveolar-arterial oxygen gradient, and respiratory dead space. The presence of concomitant ALI exacerbates these findings. PEEP identical to AP moderately improved oxygenation and respiratory mechanics; however, an important decline in stroke index and right ventricle ejection fraction was observed. Conclusions: Simultaneous IAH and ALI produce important impairments in the respiratory physiology. PEEP equalization to AP may improve the respiratory performance, nevertheless with a secondary hemodynamic derangement.

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Background: Positive surgical margin (PSM) after radical prostatectomy (RP) has been shown to be an independent predictive factor for cancer recurrence. Several investigations have correlated clinical and histopathologic findings with surgical margin status after open RP. However, few studies have addressed the predictive factors for PSM after robot-assisted laparoscopic RP (RARP). Objective: We sought to identify predictive factors for PSMs and their locations after RARP. Design, setting, and participants: We prospectively analyzed 876 consecutive patients who underwent RARP from January 2008 to May 2009. Intervention: All patients underwent RARP performed by a single surgeon with previous experience of > 1500 cases. Measurements: Stepwise logistic regression was used to identify potential predictive factors for PSM. Three logistic regression models were built: (1) one using preoperative variables only, (2) another using all variables (preoperative, intraoperative, and postoperative) combined, and (3) one created to identify potential predictive factors for PSM location. Preoperative variables entered into the models included age, body mass index (BMI), prostate-specific antigen, clinical stage, number of positive cores, percentage of positive cores, and American Urological Association symptom score. Intra-and postoperative variables analyzed were type of nerve sparing, presence of median lobe, percentage of tumor in the surgical specimen, gland size, histopathologic findings, pathologic stage, and pathologic Gleason grade. Results and limitations: In the multivariable analysis including preoperative variables, clinical stage was the only independent predictive factor for PSM, with a higher PSM rate for T3 versus T1c (odds ratio [OR]: 10.7; 95% confidence interval [CI], 2.6-43.8) and for T2 versus T1c (OR: 2.9; 95% CI, 1.9-4.6). Considering pre-, intra-, and postoperative variables combined, percentage of tumor, pathologic stage, and pathologic Gleason score were associated with increased risk of PSM in the univariable analysis (p < 0.001 for all variables). However, in the multivariable analysis, pathologic stage (pT2 vs pT1; OR: 2.9; 95% CI, 1.9-4.6) and percentage of tumor in the surgical specimen (OR: 8.7; 95% CI, 2.2-34.5; p = 0.0022) were the only independent predictive factors for PSM. Finally, BMI was shown to be an independent predictive factor(OR: 1.1; 95% CI, 1.0-1.3; p = 0.0119) for apical PSMs, with increasing BMI predicting higher incidence of apex location. Because most of our patients were referred from other centers, the biopsy technique and the number of cores were not standardized in our series. Conclusions: Clinical stage was the only preoperative variable independently associated with PSM after RARP. Pathologic stage and percentage of tumor in the surgical specimen were identified as independent predictive factors for PSMs when analyzing pre-, intra-, and postoperative variables combined. BMI was shown to be an independent predictive factor for apical PSMs. (C) 2010 European Association of Urology. Published by Elsevier B. V. All rights reserved.

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Objective. To analyze the longterm followup of a series of Brazilian patients with undifferentiated spondyloarthritis (uSpA). Methods. Prospective study analyzing a group of 111 patients with the diagnosis of uSpA, fulfilling the European Spondylarthropathy Study Group and the Amor criteria, who were followed for 5 to 10 years in a single university referral center. Patients had their outcome analyzed at 5, 7, and 10 years. Results. There was a predominance of men (81.1%), white ethnicity (78.4%), and positive HLA-B27 (61.3%), with a mean age at onset of 27.2 years. Twenty-seven patients presented development to ankylosing spondylitis (AS; 24.3%) and 3 to psoriatic arthritis (PsA; 2.7%), while 25 patients (22.5%) went into remission during the followup. Univariate logistic regression analysis revealed that ethnicity, HLA-B27, buttock pain, inflammatory low back pain, ankle involvement, grade I sacroiliitis at the beginning of the study, and the use of sulfasalazine were statistically associated with progression to AS. Multivariate logistic regression analysis revealed that HLA-B27 (p = 0.035, OR 6.720.95% CI 11.45-39.43) and buttock pain (p = 0.009, OR 6.211, 95% CI 1.591-24.25) were statistically associated with progression to AS. Conclusion. In a longterm followup of 111 Brazilian patients with uSpA, HLA-B27 and buttock pain were significant predictors of progression to a definite disease. (First Release May 1 2010; J Rheumatol 2010;37:1195-9; doi:10.3899/jrheum.090625)

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The higher frequency of triple-negative and HER-2-positive tumors detected in younger patients has been suggested as an explanation for the more aggressive tumor types observed in this age group. However, estrogen receptor (ER)-positive tumors are the most frequent subtype of breast carcinomas identified, even in younger patients. In this retrospective study, the morphological and immunohistochemical profiles of ER-positive breast carcinomas from women 35 yrs and younger that were diagnosed between 1997 and 2007 were evaluated. From these cases, 213 were selected based on the availability of pathology reports and paraffin blocks. For comparison, 117 consecutive cases of breast carcinomas diagnosed in patients >60 yrs from 2006 were included. Paraffin-embedded tumors were stained for expression of ER, progesterone receptor (PR), human epidermal growth factor receptor 2 (HER-2). Ki-67 antigen, epidermal growth factor receptor (EGFR), cytokeratin 5/6, p53, vimentin, CD117, and p63 using tissue microarrays. ER-positive carcinomas were diagnosed in 120 (56.1%) samples of the younger patient group and in 92 (78.6%) samples of the older patient group. Of these ER-positive carcinomas, 48 (40%) from the younger patient group presented the subtype luminal A, compared with 53 (57.6%) from the older patient group (p=0.01). Tumors from the younger patient group were also associated with increased vascular involvement, co-expression of HER-2, and decreased expression of CD117. These results highlight differences in expression markers and the pathology of ER-positive tumors detected in younger women, with a notable characteristic being co-expression of HER-2. (C) 2010 Elsevier Ltd. All rights reserved.

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P>Natural killer (NK) cells bridge the interface between innate and adaptive immunity and are implicated in the control of herpes simplex virus 2 (HSV-2) infection. In subjects infected with human immunodeficiency virus 1 (HIV-1), the critical impact of the innate immune response on disease progression has recently come into focus. Higher numbers of NK cells are associated with lower HIV-1 plasma viraemia. Individuals with the compound genotype of killer cell immunoglobulin-like receptor (KIR) 3DS1 and human leucocyte antigen (HLA)-Bw4-80I, or who have alleles of KIR3DL1 that encode proteins highly expressed on the NK cell surface, have a significant delay in disease progression. We studied the effect of HSV-2 co-infection in HIV-1-infected subjects, and show that HSV-2 co-infection results in a pan-lymphocytosis, with elevated absolute numbers of CD4+ and CD8+ T cells, and NK cells. The NK cells in HSV-2 co-infected subjects functioned more efficiently, with an increase in degranulation after in vitro stimulation. The number of NK cells expressing the activating receptors NKp30 and NKp46, and expressing KIR3DL1 or KIR3DS1, was inversely correlated with HIV-1 plasma viral load in subjects mono-infected with HIV-1, but not in subjects co-infected with HSV-2. This suggests that HSV-2 infection mediates changes within the NK cell population that may affect immunity in HIV-1 infection.

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Purpose: We tested whether the combination of 4 established cell cycle regulators (p53, pRB, p21 and p27) could improve the ability to predict clinical outcomes in a large multi-institutional collaboration of patients with pT3-4N0 or pTany Npositive urothelial carcinoma of the bladder. We also assessed whether the combination of molecular markers is superior to any individual biomarker. Materials and Methods: The study comprised 692 patients with pT3-4N0 or pTany Npositive urothelial carcinoma of the bladder treated with radical cystectomy and bilateral lymphadenectomy (median followup 5.3 years). Scoring was performed using advanced cell imaging and color detection software. The base model incorporated patient age, gender, stage, grade, lymphovascular invasion, number of lymph nodes removed, number of positive lymph nodes, concomitant carcinoma in situ and adjuvant chemotherapy. Results: Individual molecular markers did not improve the predictive accuracy for disease recurrence and cancer specific mortality. Combination of all 4 molecular markers into number of altered molecular markers resulted in significantly 1 higher predictive accuracy than any single biomarker (p < 0.001.). Moreover addition of number of altered molecular markers to the base model significantly improved the predictive accuracy for disease recurrence (3.9%, p < 0.001) and cancer specific mortality (4.3%, p < 0.001). Addition of number of altered molecular markers retained statistical significance for improving the prediction of clinical outcomes in the subgroup of patients with pT3N0 (280), pT4N0 (83) and pTany Npositive (329) disease (p < 0.001). Conclusions: While the status of individual molecular markers does not add sufficient value to outcome prediction in patients with advanced urothelial carcinoma of the bladder, combinations of molecular markers may improve molecular staging, prognostication and possibly prediction of response to therapy.

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The aim of the present study was to evaluate by immunohistochemistry the prognostic meaning of the tumor marker MET (hepatocyte growth factor) in patients submitted to surgical resection due to primary colorectal adenocarcinoma. Patients and Methods: A retrospective study was carried out that included 286 consecutive patients with colorectal adenocarcinoma, submitted to surgical resection at Barretos Cancer Hospital, from 1993 to 2002. The histopathological expression of the MET tumor marker was evaluated using an anti-protein monoclonal antibody against MET by the streptavidin-biotin-peroxidase technique. The expression of the tumor marker was semi-quantitative, and the slide samples were independently analyzed by three pathologists unaware of patient clinical and histopathological data. Results: The tumor marker expression was positive in 236 (79%) out of a total of 286 patients. This expression was statistically significantly different between stages I and IV (p=0.004), for overall survival (p=0.009), and for cancer-related mortality rates (p=0.022). However, no association between the tumor marker and recurrence (p=0.89) or disease-free interval (p=0.91) was observed. Conclusion: MET has shown significant expression at advanced stages of the disease, as well as for overall survival and cancer-related mortality rates demonstrating to be a valuable marker for poor prognosis in colorectal cancer patients.

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Background: Obstructive sleep apnoea-hypopnoea syndrome (OSAHS) is a respiratory disorder with high morbidity and mortality. Continuous positive airway pressure (CPAP) is the most commonly prescribed conservative treatment for adults with OSAHS. CPAP therapy normalises or decreases OSAHS symptoms and can reduce and prevent OSAHS complications. Aims: To evaluate adherence to nasal CPAP treatment and CPAP impact on daytime drowsiness. Method: A sample of 20 patients evaluated for daytime drowsiness using the Epworth sleepiness scale and interviewed for adherence to nasal CPAP use. Results: There was a significant decrease in the level of daytime sleepiness of the patients users of nasal CPAP (p=0.017); patients not using nasal CPAP experienced a decrease without statistical significance (p=0.162). 100% of CPAP users reported benefits and 50% of these reported related discomforts. Conclusions: Patients with OSAHS that use CPAP have a greater reduced level of sleepiness than those who do not use it.

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In order to quantify presence of residual BCC in patients with histologic positive margins after the first excison and to correlate the presence of residual tumor in re-excised lesions with the location of the positive margin on the first excision, a retrospective evaluation of 2053 surgically treated BCC was performed. Only 38.3% of the re-excised lesions showed residual tumor. In the group of re-excised lesions where residual BCC was found, 13% had lateral positive margin in the first excision, 39% had deep positive margin and 48% had both lateral and deep positive margins. In the group of re-excised lesions where no residual BCC was found, 49% of the primary excised lesions had lateral positive margin, 32% had deep positive margin and 19% had both deep and lateral positive margins. The association between residual tumor and positive margins was statistically significant (p = 0.01). Our findings confirm that presence of residual tumour is more likely when both lateral and deep margins are compromised.

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Parenteral nutrition therapy is used in patients with a contraindication to the use of the gastrointestinal tract, and infection is one of its Frequent and severe complications. The objective of the present study was to detect the presence of biofilms and microorganisms adhering to the central venous. catheters used for parenteral nutrition therapy by scanning electron microscopy. Thirty-nine central venous catheters belonging to patients with clinical signs of infection (G I) and asymptomatic patients (G2) and patients receiving central venous catheters for clinical monitoring (G3) were analyzed by semi-quantitative culture and scanning electron microscopy. The central venous catheters of G1 presented more positive cultures than those of G2 and G3 (81% vs 50% and 0%, respectively). However, biofilms were observed in all catheters used and 55% of them showed structures that suggested central venous catheters colonization by microorganisms. Approximately 53% of the catheter infections evolved with systemic infection confirmed by blood Culture. The authors conclude that the presence of a biofilm is frequent and is all indicator of predisposition to infection, which may even occur in patients who are still asymptomatic. (JPEN J Parenter Enteral Nutr. 2009;33:397-403)

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Autoimmune hepatitis is an inflammatory chronic disease of the liver, which frequently results in cirrhosis. The present study aimed to verify the relationship between plasma cells and stellate cells in autoimmune hepatitis. Thirty-three pre-treatment, 11 post-treatment, and 10 normal liver biopsies were reviewed. Sirius Red staining (for semi-quantitative analysis of hepatic fibrosis) and immunohistochemistry were carried out: double staining for smooth muscle alpha-actin and plasma cell marker (for detection and localization of activated hepatic stellate cells and plasma cells, respectively); and single staining for glial fibrillary acid protein (for detection of hepatic stellate cells). We found an increase in the stellate cell population, mainly with an activated phenotype in autoimmune hepatitis, compared to the control group (liver specimens with no histological evidence of liver disease, obtained from patients undergoing hepatic resection for benign liver mass). A positive significant correlation was observed between stellate cells and scores of fibrosis (measured by Sirius Red) and the number of plasma cells. Additionally, there was a co-localization of plasma cells and activated stellate cells. We also observed a reduction in the number of plasma cells, hepatic stellate cells, and fibrosis in patients who had successfully been treated and had a second liver biopsy post-treatment. Our findings support that the number of plasma cells can be a surrogate marker for the severity of liver disease, reflecting the number of hepatic stellate cells and the amount of fibrosis. It remains to be seen if this is a result of a direct interaction between the plasma cells and hepatic stellate cells or the response to the same stimulus that affects both cellular types. (c) 2010 Elsevier GmbH. All rights reserved.

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The aims of this study were to characterize the spatial distribution of neurodegeneration after status epilepticus (SE) induced by either systemic (S) or intrahippocampal (H) injection of pilocarpine (PILO), two models of temporal lobe epilepsy (TLE), using FluoroJade (FJ) histochemistry, and to evaluate the kinetics of FJ staining in the H-PILO model. Therefore, we measured the severity of behavioral seizures during both types of SE and also evaluated the FJ staining pattern at 12, 24, and 168 h (7 days) after the H-PILO insult. We found that the amount of FJ-positive (FJ+) area was greater in SE induced by S-PILO as compared to SE induced by H-PILO. After SE induced by H-PILO, we found more FJ+ cells in the hilus of the dentate gyrus (DG) at 12 h, in CA3 at 24 h, and in CA1 at 168 h. We found also no correlation between seizure severity and the number of FJ+ cells in the hippocampus. Co-localization studies of FJ+ cells with either neuronal-specific nuclear protein (NeuN) or glial fibrillary acidic protein (GFAP) labeling 24 h after H-PILO demonstrated spatially selective neurodegeneration. Double labeling with FJ and parvalbumin (PV) showed both FJ+/PV+ and FJ+/PV- cells in hippocampus and entorhinal cortex, among other areas. The current data indicate that FJ+ areas are differentially distributed in the two TLE models and that these areas are greater in the S-PILO than in the H-PILO model. There is also a selective kinetics of FJ+ cells in the hippocampus after SE induced by H-PILO, with no association with the severity of seizures, probably as a consequence of the extra-hippocampal damage. These data point to SE induced by H-PILO as a low-mortality model of TLE, with regional spatial and temporal patterns of FJ staining. (C) 2010 Elsevier B.V. All rights reserved.

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Mucin 1 (MUC1) is a glycoprotein that is expressed on apical cell membranes in a variety of normal tissues. MUC1 is involved in cell signaling, inhibition of cell-cell and cell matrix adhesion, apoptosis, proliferation, and transcription. Hypoxia is an important factor that promotes cancer metastasis and stimulates angiogenesis and tumor progression. Hypoxia inducible factor 1 (HIF-1 alpha) and carbonic anhydrase IX (CAIX) are two molecules that are involved in this process. The role of hypoxia in MUC1+ invasive ductal breast carcinomas is not well established. In this study, the expression of MUC1 was correlated with the hypoxia-associated markers HIF-1 alpha and CAIX, as well as several immunohistochemical markers and clinicopathologic features of prognostic significance in 243 invasive ductal carcinomas. MUC1 was overexpressed in 37.0% of patients and correlated with the expression of estrogen receptor (p = 0.0001), progesterone receptor (p = 0.0001), HIF-1 alpha (p = 0.006), VEGF (p = 0.024), and p53 (p = 0.025). In breast cancer, MUC1 expression has been associated with increased degradation of inhibitor of NF-kappa B (I kappa B alpha), driving NF-kappa B to the nucleus and blocking apoptosis and promoting cell survival. We analyzed NF-kappa B expression in MUC1+ breast carcinoma and found a very significant relationship between these proteins (p = 0.0001). Our findings indicate that MUC1 may play a role in the regulation of hormone receptors by increasing the inactivation of p53 and targeting NF-kappa B to the nucleus. Our data also support the notion that activation of HIF-1 alpha in MUC1+ breast carcinomas may modulate VEGF expression, allowing a metabolic adaptation to hypoxia.