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《Pharmaceutical biology》2013,51(5):545-553
In order to explore rationally the medical potential of the plant biodiversity of the Central and South American region as a source of novel antiparasitic molecules, a multinational Organization of American States (OAS) project, which included the participation of multidisciplinary research centers from Argentina, Bolivia, Colombia, Costa Rica, Guatemala, Nicaragua and Panama, was carried out during the period 2001-2004. This project aimed at screening organic plant extracts for antitrypanosomal, antileishmanial and antimalarial activities and subsequently isolating and characterizing bioactive molecules. Plants for antiparasitic screening were selected from a database of ethnomedical uses of Latin American plants (PlanMedia) based on the amount of biological and chemical information available in the literature. We report here the evaluation of 452 extracts from 311 plant species in vitro screens against Plasmodium falciparum, Leishmania mexicana, and Trypanosoma cruzi. Out of 311 species tested, 17 plants (5.4%) showed antiparasitic activities at IC50 values?≤?10?µg/mL. The most active plants were Acnistus arborescens (L.) Schltdl. (Solanaceae) (leaf, EtOH, IC50: 4?µg/mL) Monochaetum myrtoideum Naudin (Melastomataceae) (leaf, MeOH, IC50: 5?µg/mL) and Bourreria huanita (Lex.) Hemsl. (Boraginaceae) (branch, EtOH, IC50: 6?µg/mL). These were selectively active against P. falciparum, L. mexicana and T. cruzi, respectively.  相似文献   
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BackgroundOutcomes of newly diagnosed multiple myeloma (NDMM) in developing regions have not paralleled those in developed settings. Economic disadvantage, comorbidities, and aggressive disease behavior play competing roles on defining outcomes. Our aim was to analyze the impact of socioeconomic characteristics and comorbidities on therapy initiation, drug selection, and survival outcomes of NDMM in a resource-constrained setting.Patients and MethodsThis retrospective single-center cohort included ≥ 18-year-old NDMM patients from January 2006 to December 2018.ResultsA total of 245 patients were included with a median age of 62 years, Eastern Cooperative Oncology Group performance status ≤ 2 in 70.2%, International Staging System score ≥ 2 in 89.4%, and high-risk disease in 31.6%. Comorbidities were reported in 69.4%, and Charlson comorbidity index (CCI) was ≥ 2 in 64.1%. A total of 87.4% (n = 214) received thalidomide-, alkylating-, and bortezomib-based induction in 67.8%, 18.2%, and 13.1%. Patient-related factors including performance status, comorbidities, and CCI, but not myeloma-related factors, were associated with a decreased likelihood of initiating induction therapy. On multivariate analysis, CCI ≥ 2 remained statistically significant (odds ratio, 5.81; P = .005). Overall survival was 44 months. Although both patient- and myeloma-related factors were associated with a decreased overall survival, only International Staging System score > 2 (hazard ratio, 3.53; P = .004) and induction without bortezomib-based regimens (hazard ratio, 4.45; P < .001) were statistically significant on multivariate analysis.ConclusionMyeloma- and treatment-related factors are the main determinants of survival in NDMM induction-eligible patients. Patient-related factors play a pivotal role determining access to therapy and survival outcomes. Comorbidity index and performance status were determinant on defining therapy initiation in this real-world population, which emphasizes the need to improve health baseline conditions in resource-constrained settings.  相似文献   
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We report a case of 'delusional parasitosis by proxy'. A sixyear old child was brought to the emergency department by a mother with concerns that her son had a skin and scalp infestation. Despite the absence of any clinical findings being found on exam, the mother remained disproportionately concerned. Follow up care was recommended with the child's primary care. The mother returned to the ED with her child three weeks later with concerns that her son had an inflamed scalp and eyes. The mother remained insistent that the child was infested with bugs and she had sought care at two other locations where the child was prescribed permethrin on both visits. She had been applying the medication repeatedly. On exam the boy's scalp had been shaved and was erythematous and irritated; his eyebrows and eyelashes had also been shaved off and likely contributed to an irritant conjunctivitis from repeated applications of topical permethrin lotion. No evidence of infestation was identified. We recruited the assistance of the maternal grandparents, child protective services and primary care pediatrics and the child was removed from the mother's custody and placed into the custody of the grandparents. Six weeks later with basic skin care and erythromycin ophthalmic ointment for the eyes, the child's hair, eyebrows and eyelashes grew had grown in, and the scalp irritation had resolved. The mother had sought and received psychiatric care and was improving.  相似文献   
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The Japanese Respiratory Society 2017 guidelines strongly recommend switching from intravenous (IV) to oral antibiotics in patients with community-acquired pneumonia (CAP), following improvement in clinical symptoms and laboratory findings. Here, we retrospectively investigated the real-world, nationwide treatment and switching patterns for hospitalized patients with CAP in Japan using administrative data from 372 Japanese Diagnosis Procedure Combination hospitals from April 2010 to December 2018. Hospitalizations for CAP (patient age ≥20 years) with an A-DROP classification for CAP severity and IV antibiotics initiated on the admission date were included. Overall, 210,314 hospitalizations (moderate CAP: 61.7%) in 183,607 patients were analyzed. The median (interquartile range [IQR]) age at admission was 79 (70–86) years. Penicillin (51.9%) and cephalosporin (38.9%) were the most common IV antibiotic classes used and the median (IQR) duration of IV use was 8 (6–11) days. Switching to oral antibiotics during a hospitalization occurred in 30.1% (n = 63,311) of patients after a median (IQR) of 7 (5–10) days of IV treatment. The most frequently used oral antibiotic classes after a switch were fluoroquinolone (45.9%) and penicillin (24.8%). The switch rate was higher among hospitalizations with milder CAP, in respiratory medicine ward and in larger hospitals. The overall switch rates did not change over the study period. The findings from this analysis suggest that early switch from IV to oral antibiotics was not widely implemented during the 8 years of the study period. Further observation will be needed to see the potential impact of the guidelines update in 2017 in Japan.  相似文献   
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