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131.
132.
Enterocytozoon bieneusi is an agent of intestinal microsporidiosis leading to chronic diarrhoea in AIDS patients. Pulmonary involvement may occur but remains rare with only 4 cases reported in the literature. We report here the fifth case of pulmonary localization of E. bieneusi in a severe immunocompromized HIV-infected patient with intestinal and pulmonary symptoms.  相似文献   
133.
Various vasoactive agents have been used to modify tumor blood flow with the ultimate goal of improving cancer detection and treatment, with widely disparate results. Furthermore, the lack of mechanistic interpretations has hindered understanding of how these agents affect the different physiological parameters involved in perfusion. Thus, there is a need to develop a unified framework for understanding the interrelated physiological effects of pharmacological and physical agents, The goals of this study were (1) to develop a mathematical model which helps determine the location and magnitude of changes in the vascular resistance of tumor and normal tissues and (2) to test the model with our own experimental studies and by comparison with results from the literature. The systemic and interstitial pressures and relative tumor blood flow were measured before and after administration of angiotensin II, epinephrine, norepinephrine, nitroglycerin, and hydralazine in SCID mice bearing LS174T human colon adenocarcinoma xenografts. A mathematical model was developed in analogy to electrical circuits which examined the pressure, flow, and resistance relationships for arterial and venous segments of the vasculature of a tumor and surrounding normal tissue. Vasoconstrictor-induced increases in the mean arterial blood pressure led to increases in tumor blood flow and interstitial pressure with the magnitude of change dependent on the agent (percentage change in blood flow: angiotensin > epinephrine > norepinephrine). The vasodilating agents induced decreases in tumor blood flow in parallel to the induced decreases in the systemic pressure, but only the long-acting arterial vasodilator hydralazine was capable of effecting a decrease in tumor interstitial pressure. The model was also found to be consistent with other data available in the literature on norepinephrine, pentoxifylline, nicotinamide, and hemodilution, and was useful in providing input as to the location and degree of the physiological effects of these agents. The results of the data and model show that the steal phenomenon is the dominant mechanism for redistribution of host blood flow to the tumor. However, some degree of arterial control was found to be present in the tumors. Moreover, the parallel increases in tumor interstitial pressure and blood flow contradict any hypothesis suggesting that elevated interstitial fluid pressure precipitates chronic vascular collapse, thus decreasing blood flow.  相似文献   
134.
Peroxisome proliferator-activated receptors (PPARs) regulate storage and catabolism of fats and carbohydrates. PPARgamma activity increases insulin sensitivity and adipocyte differentiation at the expense of adipogenesis and weight gain. The goal of this study was to 1) clone the promoter of the human adipocyte fatty acid binding protein (aP2) gene, namely fatty acid-binding protein-4, 2) characterize its pharmacological regulation, and 3) determine its putative predictability for adipogenesis. Among the selected PPAR agonists, rosiglitazone and pioglitazone displayed the highest maximal efficacy (E(max)) on reporter-gene assays in COS-7 cells cotransfected by either a galactosidase 4-response element-based or a human aP2 promoter-based Luc reporter vector, along with either chimeric or full-length human PPAR expression plasmids. The non-subtype-selective 2-(4-[2-(3-[2,4-difluorophenyl]-1-heptylureido)ethyl]phenoxy)-2-methyl-butyric acid (GW-2331) and the compounds [4-[3-(4-acetyl-3-hydroxy-2-propylphenoxy)-propoxyl]phenoxy]-acetic acid (L-165041), (4-((2S,5S)-5-(2-(bis(phenylmethyl)amino)-2-oxoethyl)-2-heptyl-4-oxo-3-thiazolidinyl)butyl)-benzoic acid (GW-0072), and indomethacin behaved as partial agonists relative to pioglitazone in full-length human aP2-PPARgamma2. Beyond their partial PPARgamma agonist properties, these compounds elicited a lower maximal up-regulation of mouse aP2 mRNA in 3T3-L1 adipocytes as compared with pioglitazone; these properties paralleled a time-dependent increase in neutral lipids. By contrast, the selective PPARalpha agonist 2,2-dichloro-12-(4-chlorophenyl)dodecanoic acid (BM-17.0744) neither stimulated the human aP2-PPARalpha promoter reporter-gene assay, thus demonstrating a specific interaction between PPARgamma and the aP2 promoter, nor affected lipogenesis in 3T3-L1 cells. Altogether, these data characterized a functional promoter of the human aP2 gene; its in vitro pharmacological regulation in PPARgamma-mediated reporter-gene assay may represent an interesting complement or an alternative to time-consuming procedures aiming at discriminating PPAR ligands with low lipogenic properties.  相似文献   
135.
136.

Purpose

The aim of the study was to assess the ability of plasma neutrophil gelatinase-associated lipocalin (pNGAL) to predict acute kidney injury (AKI) in adult intensive care unit (ICU) patients.

Methods

All consecutives patients admitted to 3 ICUs were enrolled in this prospective-observational study. Plasma neutrophil gelatinase-associated lipocalin was analyzed at ICU admission. Risk, injury, failure, loss, and end-stage kidney (RIFLE) criteria were calculated at admission and for each day during the first week. Patients were classified according to whether they met the threshold for RIFLE criteria (RIFLE 0 or 1) at admission and during the first week. Four groups were identified: RIFLE (0-0), (1-1), (1-0), and (0-1).

Results

During this 1-month period, 88 patients were included in the study. Thirty-six patients met the criteria for RIFLE 0-0 with a mean pNGAL of 98 ± 60 nmol/L, 22 for RIFLE 1-1 with a mean pNGAL of 516 ± 221 nmol/L, and 20 patients had no AKI at admission but develop AKI at 48 hours (24-96 hours) (RIFLE 0-1) with a pNGAL of 342 ± 183 nmol/L. Ten patients met the criteria for RIFLE 1-0 and had a mean pNGAL of 169 ± 100 nmol/L. Using a cutoff of 155 nmol/L, sensitivity and specificity to predict AKI were 82% and 97%, respectively (area under the curve [AUC] = 0.92 [0.852-0.972]; P = .001). Looking at the patients without AKI at admission (n = 56) and who developed (n = 20) or did not develop (n = 36) AKI, receiver operating characteristic curve analysis was as follows: AUC = 0.956 (0.864-0.992). Sensitivity was 85% and specificity was 97%. Of the 7 patients who required renal replacement therapy, all of them had pNGAL of more than 303 nmol/L (AUC = 0.788 [0.687-0.868]).

Conclusion

Plasma neutrophil gelatinase-associated lipocalin at ICU admission is an early biomarker of AKI in adult ICU patients. Plasma neutrophil gelatinase-associated lipocalin increased 48 hours before RIFLE criteria.  相似文献   
137.
In chronic myeloid leukemia (CML), cytogenetic abnormalities found in addition to the t(9;22) translocation may impact the response to therapy. Loss of the Y chromosome is generally overlooked in this context, owing to its relatively frequent occurrence in healthy elderly patients. In this multicenter retrospective study, the outcome after imatinib treatment of 30 CML patients with karyotype showing Y chromosome loss (Y−) was compared to 30 Y+ control males diagnosed and treated at the same time in the same institutions. Y− patients had significantly delayed cytogenetic and molecular responses, lower event-free survival and shorter overall survival than Y+ patients. The negative impact of this abnormality was particularly marked when it occurred in a sub-clone (clonal evolution) rather than in all mitoses. These data indicate that loss of the Y chromosome should be taken into account in the prognostic evaluation of chronic myelogenous leukemia patients.  相似文献   
138.
With the advent of new gray scale imaging techniques, ultrasound plays a major role in the diagnosis of pancreatic lesions. As a noninvasive, nonionizing, accurate, and inexpensive diagnostic modality that directly images the pancreatic gland, ultrasound can be used as a primary screening tool. It is helpful in confirming the diagnosis of acute pancreatitis and in detecting and following pseudocysts and other complications. Neoplasms can be detected with a high rate of accuracy, and by assessing the presence of ascites or metastatic foci in the liver, ultrasound can aid in the staging of the neoplastic process. Bowel gas and obesity remain serious limitations to adequate examination, and in these patients computed tomography offers a complementary modality.  相似文献   
139.
We examined the outcome of a cohort of patients with Hodgkin lymphoma (HL) in order to assess if fluorodeoxyglucose (FDG) positron emission tomography–computed tomography (PET/CT) at the end of treatment (end‐PET) can be omitted when the interim PET (int‐PET) is negative. Seventy‐six ABVD(adriamycin, bleomycin, vinblastine, dacarbazine)‐treated patients were retrospectively included. No change in treatment was made on the basis of int‐PET results. Suspicious foci on end‐PET received biopsy confirmation whenever possible. Median follow‐up was 58·9 months. Uptake on int‐PET higher than liver (scores 4–5) was rated positive according to the Lugano classification, while a positive end‐PET corresponded to scores 3, 4 and 5. Fifteen patients had treatment failure. Sensitivity, specificity, positive predictive value (PPV), negative predictive value and accuracy of int‐PET were 46·7%, 85·2%, 43·8%, 86·7% and 77·6%, respectively. For end‐PET the figures were: 80%, 93·4%, 75%, 95% and 90·8%. Eight patients with negative int‐PET had treatment failure; six of them were identified as non‐responders with end‐PET. The 5‐year progression‐free survival (PFS) was 87% for patients with negative int‐PET versus 56% with positive int‐PET. The 5‐year PFS was 96% with negative end‐PET versus 23% with positive end‐PET. The prognostic information from int‐PET as regards PFS (log‐rank test = 0·0048) was lower than that provided by end‐PET (< 0·0001). Int‐PET predicted only half of the failures. When used in clinical routine, a negative int‐PET study cannot obviate the need for end‐PET examination.  相似文献   
140.
Extranodal NK/T-cell lymphoma, nasal type, is a rare and highly aggressive disease with a grim prognosis. No therapeutic strategy is currently identified in relapsing patients. We report the results of a French prospective phase II trial of an L-asparaginase-containing regimen in 19 patients with relapsed or refractory disease treated in 13 centers. Eleven patients were in relapse and 8 patients were refractory to their first line of treatment. L-Asparaginase-based treatment yielded objective responses in 14 of the 18 evaluable patients after 3 cycles. Eleven patients entered complete remission (61%), and only 4 of them relapsed. The median overall survival time was 1 year, with a median response duration of 12 months. The main adverse events were hepatitis, cytopenia, and allergy. The absence of antiasparaginase antibodies and the disappearance of Epstein-Barr virus serum DNA were significantly associated with a better outcome. These data confirm the excellent activity of L-asparaginase-containing regimens in extranodal NK/T-cell lymphoma. L-Asparaginase-based treatment should thus be considered for salvage therapy, especially in patients with disseminated disease. First-line L-asparaginase combination therapy for extranodal NK/T-cell lymphoma warrants evaluation in prospective trials. This trial is registered at www.clinicaltrials.gov as #NCT00283985.  相似文献   
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