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51.
Pneumocystis pneumonia (PCP) has been considered a rare disease in sub-Saharan Africa. However, a rising prevalence has been noted recently. The objective of this study was to determine the relative prevalence of PCP and other pulmonary opportunistic diseases in patients infected with HIV in Ethiopia. 131 consecutive patients with respiratory symptoms and atypical chest X-ray, who were sputum smear-negative for AFB and seroreactive for HIV, underwent clinical evaluation and investigation for Pneumocystis jiroveci and Mycobacterium tuberculosis from sputum and bronchoalveolar lavage (BAL), and fungal and bacterial pathogens from BAL alone. Bacterial infections, Pneumocystis pneumonia (PCP) and pulmonary tuberculosis (PTB) occurred in 44 (33.6%), 39 (29.7%) and 31 (23.7%) patients, respectively. Pulmonary Kaposi sarcoma and non-specific interstitial pneumonitis occurred in 4 patients each. In a multivariate regression model, predictors of PCP were typical chest X-ray and low CD4 count while purulent sputum predicted bacterial infection. The sensitivity of physicians and chest X-ray diagnosis was particularly low for PTB and bacterial infections. We conclude that chronic bacterial infection and Pneumocystis pneumonia are important differential diagnoses in HIV-infected, smear-negative PTB patients presenting with atypical chest X-ray. We therefore need to escalate the use of preventive and highly active antiretroviral (HAART) treatment in order to prevent a PCP epidemic.  相似文献   
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Khan H  Belsher J  Yilmaz M  Afessa B  Winters JL  Moore SB  Hubmayr RD  Gajic O 《Chest》2007,131(5):1308-1314
BACKGROUND: Transfusion has long been identified as a risk factor for acute lung injury (ALI)/ARDS. No study has formally evaluated the transfusion of specific blood products as a risk factor for ALI/ARDS in critically ill medical patients. METHOD: In this single-center retrospective cohort study, 841 consecutive critically ill patients were studied for the development of ALI/ARDS. Patients who received blood product transfusions were compared with those who did not, in univariate and multivariate propensity analyses. RESULTS: Two hundred ninety-eight patients (35%) received blood transfusions. Transfused patients were older (mean [+/- SD] age, 67 +/- 17 years vs 62 +/- 19 years; p < 0.001) and had higher acute physiologic and chronic health evaluation (APACHE) III scores (74 +/- 32 vs 58 +/- 23; p < 0.001) than those who had not received transfusions. ALI/ARDS developed more commonly (25% vs 18%; p = 0.025) in patients exposed to transfusion. Seventeen patients received massive RBC transfusions (ie, > 10 U of blood transfused within 24 h), of whom 13 also received fresh-frozen plasma (FFP) and 11 received platelet transfusions. When adjusted for the probability of transfusion and other ALI/ARDS risk factors, any transfusion was associated with the development of ALI/ARDS (odds ratio [OR], 2.14; 95% confidence interval [CI], 1.24 to 3.75). Among those patients receiving individual blood products, ALI/ARDS was more likely to develop in patients who received FFP transfusions (OR, 2.48; 95% CI, 1.29 to 4.74) and platelet transfusions (OR, 3.89; 95% CI, 1.36 to 11.52) than in those who received only RBC transfusions (OR, 1.39; 95% CI, 0.79 to 2.43). CONCLUSION: Transfusion is associated with an increased risk of the development of ALI/ARDS in critically ill medical patients. The risk is higher with transfusions of plasma-rich blood products, FFP, and platelets, than with RBCs.  相似文献   
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Bone marrow-derived mesenchymal stem cells (MSCs) have been shown to localize to gliomas and deliver therapeutic agents. However, the clinical translation of MSCs remains poorly defined because previous studies relied on glioma models with uncertain relevance to human disease, typically xenograft models in immunocompromised mice. To address this shortcoming, we used the RCAS/Ntv-a system, in which endogenous gliomas that recapitulate the tumor and stromal features of human gliomas develop in immunocompetent mice. MSCs were harvested from bonemarrowof Ntv-a mice and injected into the carotid artery of Ntv-a mice previously inoculated with RCAS-PDGF-B and RCAS-IGFBP2 to induce malignant gliomas (n = 9). MSCs were labeled with luciferase for in vivo bioluminescence imaging (BLI). After intra-arterial injection, BLI revealed MSCs in the right frontal lobe in seven of nine mice. At necropsy, gliomas were detected within the right frontal lobe in all these mice, correlating with the location of the MSCs. In the twomice without MSCs based on BLI, no tumor was found, indicating thatMSC localization was tumor specific. In another cohort of mice (n = 9), MSCs were labeled with SP-DiI, a fluorescent vital dye. After intra-arterial injection, fluorescence microscopy revealed SP-DiI-labeled MSCs throughout tumors 1 to 7 days after injection but not in nontumoral areas of the brain. MSCs injected intravenously did not localize to tumors (n = 12). We conclude that syngeneic MSCs are capable of homing to endogenous gliomas in immunocompetent mice. These findings support the use of MSCs as tumor-specific delivery vehicles for treating gliomas.  相似文献   
56.

Background

Elevations in cardiac troponin have prognostic importance in critically ill patients. However, there are no data addressing the independent association between troponin levels and mortality, adjusted for the severity of the underlying disease, in patients hospitalized for acute respiratory disorders. We investigated whether troponin T (cTnT) elevations are independently associated with in-hospital mortality in patients in the intensive care unit (ICU) admitted for severe and acute respiratory conditions. After adjusting for the severity of disease measured by the Acute Physiology, Age, and Chronic Health Evaluation (APACHE) III prognostic system, we evaluated short-term (30 days) and long-term (3 years) mortality.

Methods

We studied the APACHE III database and cTnT levels from patients admitted consecutively to the ICU at Mayo Clinic, Rochester, Minnesota. Between January 2001 and December 2005, 2078 patients with respiratory conditions had cTnT measured at ICU admission. In-hospital, short-term (30 days) and long-term (3 years) all-cause mortality were determined.

Results

Of the study patients, 878 (42.3%) had elevated cTnT and 1200 patients (57.7%) had undetectable cTnT. During hospitalization, 1.1% of the patients with troponin T <0.01 ng/mL died compared to 21% of those with troponin T ≥0.01 ng/mL (P <.0001). At 30 days, mortality was 18.6% in patients with elevations of cTnT and 1.5% in patients without elevations of cTnT (P <.0001). The Kaplan-Meier probability of survival at 1-year follow-up was 71.0%, at 2-year follow-up was 48.3%, and 3-year follow-up was 39.4% with troponin T ≥0.01 ng/mL and at 1-year follow-up was 98.8%, at 2-year follow-up was 97.2%, and at 3-year follow-up was 95.5% with troponin T <0.01 μg/L (P <.0001). After adjustment for severity of disease and baseline characteristics, cTnT levels remained associated with in-hospital, short-term and long-term mortality (P <.0001).

Conclusions

In patients admitted to the ICU for respiratory disorders, cTnT elevations are independently associated with in-hospital, short-term and long-term mortality.  相似文献   
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A study was conducted to determine the role of non-biting cyclorrhaphan flies as carriers of intestinal parasites in slum areas of Addis Ababa from January 2004 to June 2004. A total of 9550 flies, comprising of at least seven species were collected from four selected sites and examined for human intestinal parasites using the formol-ether concentration method. The dominant fly species was Chrysomya rufifacies (34.9%) followed by Musca domestica (31%), Musca sorbens (20.5.%), Lucina cuprina (6.8%), Sarcophaga sp. (2.8%), Calliphora vicina (2.2%) and Wohlfahrtia sp. (1.8%). Six intestinal helminths (Ascaris lumbricoides, Trichuris trichiura, hookworms, Hymenolepis nana, Taenia spp. and Strongyloides stercoralis) and at least four protozoan parasites (Entamoeba histolytica/dispar, Entamoeba coli, Giardia lamblia and Cryptosporidium sp.) were isolated from both the external and gut contents of the flies. A. lumbricoides and T. trichiura among the helminths and E. histolytica/dispar and E. coli among the protozoans were the dominant parasites detected both on the external and in the gut contents of the flies, but occurring more in the latter. Among the flies, C. rufifacies and M. sorbens were the highest carriers of the helminth and protozoan parasites, respectively. The public health significance of these findings is highlighted.  相似文献   
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Novel therapies are clearly needed for gliomas, and the combination of oncolytic vectors with chemotherapy possesses a significant hope for the treatment of this malignancy. In addition, combination with chemotherapy allows for lower virus doses to achieve anticancer effect, thus resulting in lower undesirable toxicities due to viral proteins. In this work, we sought to determine whether combination of an oncolytic adenovirus ICOVIR-5, with RAD001 or temozolomide (TMZ) could result in enhanced anti-glioma effect in vivo. We assessed the in vitro cytotoxic effect and replication properties of ICOVIR-5 in combination with RAD001 or TMZ in U87 MG glioma cell line by MTT and TCID(50), respectively. Our data showed that in vitro treatment with RAD001 or TMZ not only interfered with adenovirus replication but, in addition, enhanced its oncolytic properties. To evaluate the in vivo anticancer effect, athymic mice bearing glioma xenografts (5 x 10(5) U87 MG cells/animal) received a single intratumoral injection of ICOVIR-5 (10(7) PFU/animal). RAD001 was given as a regimen of 5 mg/kg 5 days per week until the end of the experiment and TMZ was administered for 5 days at 7.5 mg/kg/mice. Of significance, combination of ICOVIR-5 with RAD001 or TMZ showed a potent anti-glioma effect in vivo, resulting in a dramatic extension of the median animal survival and in 20-40% animals becoming free of disease beyond 90 days.  相似文献   
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