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81.
OBJECTIVE: This study was designed to investigate the effect of allogeneic haematopoietic stem cell transplantation (HSCT) on cytomegalovirus (CMV) shedding in the saliva by nested polymerase chain reaction (nested PCR) and its impact on patient survival. PATIENTS AND METHODS: One hundred and twenty-four HSCT patients and 124 healthy volunteers were included in the study. Oral swabs were taken before, after 100 days and 1 year of HSCT at the buccal mucosa. Nested PCR was used to detect CMV in the saliva. Time of death after HSCT was displayed, by means of the Kaplan-Meier method, for the following parameters: age and gender of the patient, donor gender, primary disease, stem cell source, platelet number, chronic graft vs host disease (cGVHD) of salivary glands and oral mucosa, and oral CMV shedding. Cox proportional hazards model was used for multivariate survival analysis. RESULTS: While none of the individuals in the control group showed positive swabs for CMV, the frequency of positive CMV oral swabs in patients at day + 100 after HSCT (45.2%) was statistically higher than before (7.2%) and 1 year after HSCT (17.5%). The presence of CMV was not associated with cGVHD and did not have any impact on post-transplant survival. CONCLUSIONS: The present study shows that oral CMV shedding occurs after HSCT, especially at day +100 post-transplant. Identification of CMV in the saliva might be important for the early diagnosis of CMV infection in allo-HSTC.  相似文献   
82.
We report a case of a diabetic patient with localized osteoarticular sporotrichosis followed by widespread dissemination of the infection, which was successfully treated with amphotericin B. In addition, we evaluated the in vitro antifungal activity of 4 agents against both the mycelial and the yeast forms of the isolated fungus.  相似文献   
83.
Neurosurgical Review - Traumatic brain injury (TBI) is the main cause of pediatric trauma death and disability worldwide. Recent studies have sought to identify biomarkers of TBI for the purpose of...  相似文献   
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Neurological outcomes (Gesell development schedules [GDS]), age of walking, and age of talking were studied in 299 toddlers (12 to 24 mo) in relation to environmental (fish consumption and tin mining) exposure. Exposure to fish methylmercury (MeHg) consumption and iatrogenic ethylmercury (EtHg) in Thimerosal-containing vaccines (TCV) was quantified in toddlers from two rural villages (n?=?91, Itapuã; n?=?218, Bom Futuro) respectively populated by fishers and cassiterite miners. Median total hair Hg (HHg) concentrations of infants from Itapuã (3.5 μg/g) were significantly higher than those of infants from Bom Futuro (2.2 μg/g). Median EtHg exposure from TCV was also significantly higher in toddlers from Itapuã (137.5 μg) than in those from Bom Futuro (112.5 μg). There were no significant differences between groups for any of the Gesell schedules; however, there were proportionally more compromised toddlers (GDS < 70) in Itapuã than Bom Futuro. Median age of talking was not statistically different but median age of walking was significantly higher in Bom Futuro. In toddlers from both villages, of fishers and miners, HHg concentrations were significantly correlated with family fish consumption. A logistic regression model was applied to all infants after classification into two groups: above or below the median Gesell schedules. Overall, there was no distinctive pattern of neurodevelopment associated with either HHg or EtHg exposure; however, nutritional status was significantly associated with GDS. In conclusion, milestone achievement was delayed in toddlers from tin-ore mining communities. Despite significantly higher exposure to both forms of organic Hg (MeHg from maternal fish consumption, and EtHg from TCV) in toddlers from the fishing village, significant differences were seen only among the proportions of most severely affected toddlers (GDS < 70).  相似文献   
87.
This study assessed the transgenerational effects of insecticides in developing Trichogramma galloi (Hymenoptera: Trichogrammatidae). Laboratory bioassays were performed in which five insecticides were sprayed on egg-larval, pre-pupal and pupal stages of the parasitoid. The interaction between insecticides and development stages of the parasitoid was not significant for the rate of F0 emergence. All insecticides significantly reduced the emergence of wasps, with the lowest emergence observed when they were applied to the pupal stage. For the sex ratio, only spinosad applied to the pre-pupal stage and triflumuron applied on the egg-larval and pre-pupal stages did not differ from the controls. Triflumuron applied to pre-pupae did not lead to any difference in the parasitism rate of the treated generation (F0) when compared to the control. There were no significant differences among survival curves for females of F0 when all insecticides were sprayed on the egg-larval stage. Both concentrations of lambda-cyhalothrin + thiamethoxam reduced female pre-pupal survival, and all treatments reduced female pupal survival. In addition, we observed a transgenerational effect of the insecticides on emergence and sex ratio of next generation (F1). Lambda-cyhalothrin + thiamethoxam (Min) applied to the pre-pupae and pupae, the maximum rate of the same insecticides applied to the egg-larvae and pre-pupae, and spinosad applied to pre-pupae all significantly reduced the adults emergence of T. galloi F1 generation. Only triflumuron did not alter the F1 sex ratio. These bioassays provide a basis for better understanding the effects of insecticide use on beneficial parasitoids.  相似文献   
88.
Fuel cells are emerging devices as clean and renewable energy sources, provided their efficiency is increased. In this work, we prepared nanocomposites based on multiwalled carbon nanotubes (MWNTs) and transition metal dichalcogenides (TMDs), namely WS2 and MoS2, and evaluated their performance as electrocatalysts for the oxygen evolution reaction (OER) and the oxygen reduction reaction (ORR), relevant to fuel cells. The one- and two-dimensional (1D and 2D) building blocks were initially exfoliated and non-covalently functionalized by surfactants of opposite charge in aqueous media (tetradecyltrimethylammonium bromide, TTAB, for the nanotubes and sodium cholate, SC, for the dichalcogenides), and thereafter, the three-dimensional (3D) MoS2@MWNT and WS2@MWNT composites were assembled via surfactant-mediated electrostatic interactions. The nanocomposites were characterized by scanning electron microscopy (SEM) and structural differences were found. WS2@MWNT and MoS2@MWNT show moderate ORR performance with potential onsets of 0.71 and 0.73 V vs. RHE respectively, and diffusion-limiting current densities of −1.87 and −2.74 mA·cm−2, respectively. Both materials present, however, better tolerance to methanol crossover when compared to Pt/C and good stability. Regarding OER performance, MoS2@MWNT exhibits promising results, with η10 and jmax of 0.55 V and 17.96 mA·cm−2, respectively. The fabrication method presented here is cost-effective, robust and versatile, opening the doors for the optimization of electrocatalysts’ performance.  相似文献   
89.
A Western blot method that uses antigens from culture promastigote forms of Leishmania (Viannia) braziliensis, L. (Leishmania) amazonensis, L. (Leishmania) tropica, and a trypanosomatid (strain 268T) isolated from naturally infected tomatoes was evaluated for laboratory diagnosis of American tegumentary leishmaniasis (ATL). Serum samples were obtained from 108 patients with ATL (group I), 23 chagasic patients (group II), 32 patients with other diseases (group III), and 78 healthy individuals (group IV). The overall analysis showed a sensitivity of 76.90%, 90.40%, 78.50%, and 87.90%, a specificity of 100%, 93.80%, 87.80%, and 77.10%, a positive predictive value of 100%, 94.00%, 89.50%, and 72.50%, a negative predictive value of 75.70%, 90.00%, 75.40%, and 90.20%, and a concordance coefficient kappa of 0.7358, 0.8400, 0.6491, and 0.6287 for L. (V.) braziliensis, L. (L.) amazonensis, L. (L.) tropica, and strain 268T antigens, respectively. The antigenic profile recognized by serum samples from patients with ATL and with Chagas' disease permits serologic distinction between these infections.  相似文献   
90.
Anatomically, functionally, and clinically, peptic ulcer patients are a heterogeneous group of subjects. These patients can be classified according to the anatomic localization of the niche. The functional state of the gastric mucosa was studied in 30 gastric ulcer patients, 25 duodenal ulcer patients, and 10 normal controls. The classification of the first group was based on Johnson's criteria, with the following results: 10 individuals were type I, 10 were type II, and 10 were type III. Pepsinogen I levels and gastric acid secretion were measured in all 65 subjects under basal conditions and after subcutaneous pentagastrin stimulation. Both basal and stimulated serum pepsinogen I values were significantly higher (p less than 0.05) in gastric ulcer type III patients than in the other four groups. These values in gastric ulcer type I were similar to those of the controls. Gastric ulcer type II patients showed an intermediate functional state similar to that of duodenal ulcer patients. In both gastric ulcer type II and duodenal ulcer patients, the basal and stimulated pepsinogen I levels were significantly higher (p less than 0.05) than those found in controls, whereas the basal serum gastrin levels were similar in the five groups. In conclusion, different HCl and pepsinogen I secretory patterns, with functional heterogenicity of the gastric mucosa, are shown here for the anatomically defined gastric ulcer subsets.  相似文献   
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