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21.
Metabolic Brain Disease - Parkinson’s disease (PD) is a neurodegenerative disorder etiologically linked to the loss of substantia nigra (SN) dopaminergic neurons in the mid-brain. The...  相似文献   
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Erythrocyte invasion by Plasmodium vivax is completely dependent on binding to the Duffy blood group antigen by the parasite Duffy binding protein (DBP). The receptor-binding domain of this protein lies within a cysteine-rich region referred to as region II (DBPII). To examine whether antibody responses to DBP correlate with age-acquired immunity to P. vivax, antibodies to recombinant DBP (rDBP) were measured in 551 individuals residing in a village endemic for P. vivax in Papua New Guinea, and linear epitopes mapped in the critical binding region of DBPII. Antibody levels to rDBP(II) increased with age. Four dominant linear epitopes were identified, and the number of linear epitopes recognized by semi-immune individuals increased with age, suggesting greater recognition with repeated infection. Some individuals had antibodies to rDBP(II) but not to the linear epitopes, indicating the presence of conformational epitopes. This occurred in younger individuals or subjects acutely infected for the first time with P. vivax, indicating that repeated infection is required for recognition of linear epitopes. All four dominant B-cell epitopes contained polymorphic residues, three of which showed variant-specific serologic responses in over 10% of subjects examined. In conclusion, these results demonstrate age-dependent and variant-specific antibody responses to DBPII and implicate this molecule in partial acquired immunity to P. vivax in populations in endemic areas.  相似文献   
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The problem of morphine tolerance and dependence is a universal phenomenon threatening social health everywhere the world. The major objective of this paper was to investigate the effects of fruit essential oil (FEO) of Cuminum cyminum on acquisition and expression of morphine tolerance and dependence in mice. Animals were rendered dependent on morphine using the well-established method in which was morphine (50, 50, 75 mg/kg; s.c.) injected three times daily for 3 days. In experimental groups, administration of FEO (0.001, 0.01, 0.1, 0.5, 1 and 2%; 5 ml/kg; i.p.) or Tween-80 (5 ml/kg; i.p.) was performed 60 min prior to each morphine injection (for acquisition) or the last injection of morphine on test day (for expression). Morphine tolerance was measured by tail-flick before and after administration of a single dose of morphine (50 mg/kg; s.c.) in test day (4th day). Morphine dependence was also evaluated by counting the number of jumps after injection of naloxone (5 mg/kg; i.p.) on the test day. The results showed that Cumin FEO, only at the dose of 2%, significantly attenuated the development of morphine tolerance (P < 0.01) and dependence (P < 0.05) while it could be significantly effective on expression of morphine tolerance (1 and 2%) and dependence (0.5, 1 and 2%) in a dose-dependent manner. Solely Cumin FEO injection (0.001–2%) did not show any analgesic effect. In conclusion, the essential oil of Cuminum cyminum seems to ameliorate the morphine tolerance and dependence in mice.  相似文献   
25.
This study was carried out to describe the anatomical, histological and mucinous histochemical characteristics of the tongue in the Persian squirrel. This species is a rodent distributed all over the Middle East and recently has been considered a companion animal. Anatomical observations showed the median sulcus on the apex and absence of a lingual prominence in the body. Light and scanning electron microscopy showed that the filiform papillae cover the entire dorsal surface of the tongue, and their sizes increased approaching the root. The fungiform papillae, which contained 1–4 taste buds, were scattered on the apex, margin, body and root of the tongue. Three vallate papillae were observed on the root, each one surrounded by a groove and crescent pad with taste buds on its lateral walls. The foliate papillae on both margins of the tongue contained several laminae with taste buds. The core of the tongue was composed of lingual glands, skeletal muscles and connective tissues. These glands were confined to the body and root, which were composed of serous cells located anteriorly and mucosal and seromucosal cells placed posteriorly. The mucin histochemistry using the periodic acid-Schiff (PAS), alcian blue (AB) (pH 1.0 and 2.5), PAS–AB (pH 2.5) and aldehyde fuchsin-AB (pH 2.5) techniques showed that the mucosal content included both carboxylated and sulfated acidic mucins with neutral mucins. The results of this study could contribute to the knowledge of the morphological characteristics of the wild animal tongue and provide data for comparison with other rodents.  相似文献   
26.
Introduction  Pemphigus vulgaris (PV), an autoimmune disease affecting the skin and mucous membranes, is associated with some human leukocyte antigen (HLA) class II alleles and haplotypes. Materials and Methods  In order to evaluate the association of HLA-DR and DQ alleles and haplotypes in Iranian non-Jewish patients with PV, 52 patients with PV and 180 normal subjects as control group were investigated in this study. Results and Discussion  HLA-DRB1*04, -DRB1*1401, -DRB4, -DQA1*0104, -DQA1*03011, -DQB1*0302, and -DQB1*0502 alleles have been significantly increased in our patients group. Moreover, the haplotypes HLA-DRB1*04/-DQA1*03011/-DQB1*0302 and HLA-DRB1*1401/-DQA1*0104/-DQB1*0502 increased significantly in our patients. In contrast, the following alleles decreased significantly in our patients: HLA-DRB1*15, -DRB1*0301, -DRB1*07, -DRB1*11, -DRB5, -DQA1*0101, -DQA1*0103, -DQA1*201, -DQA1*05, -DQB1*0201, -DQB1*0301, -DQB1*06011, and -DQB1*0602. In addition, HLA-DRB1*15/-DQA1*0103/-DQB1*06011, HLA-DRB1*0301/-DQA1*05011/-DQB1*0201, HLA-DRB1*07/-DQA1*0201/-DQB1*0201, and HLA-DRB1*11/-DQA1*05/-DQB1*03011 decreased significantly in our patients. Genetic factors are involved in the occurrence of PV; HLA-DRB1*04 and -DRB1*1401 alleles and the related haplotypes are suggestive to be two major PV susceptibility factors in our population study.  相似文献   
27.
Arthritis associated with panniculitis complicating pancreatitis is well described in the literature, usually associated with osteonecrosis. Chondronecrosis has not been reported before in association with pancreatitis. We report a patient with chronic pancreatitis who presented with polyarthritis, panniculitis, osteonecrosis, but in addition had clear evidence of chondronecrosis. We suggest that direct extension of noxious materials from nearby subchondral osteonecrotic bone lesion could be the cause of the osteonecrosis and one of the pathological mechanisms leading to arthritis in patients with pancreatitis.  相似文献   
28.
Aim: To estimate the prevalence of infant anaemia and its association with iron deficiency, growth, infection and other micronutrient deficiencies. Methods: Using data from MINIMat, a randomized maternal food and micronutrient supplementation trial, we assessed the associations between anaemia (haemoglobin < 105 g/L) in 580 infants at 6 months and deficiencies of iron, vitamin A, vitamin B12, zinc and folate, infection and anthropometric indices. Variables associated with anaemia in bivariate analyses were evaluated in logistic regression models, adjusting for potential confounders. Results: Anaemia was found in 46% of the infants, and among these, 28% had iron deficiency (plasma ferritin <9 μg/L). Elevated C‐reactive protein (>10mg/L) (OR = 2.7, 95% CI: 1.6, 4.7), low birthweight (OR = 2.3, 95% CI: 1.5, 3.5) and iron deficiency (OR = 2.2, 95% CI: 1.4, 3.6) were independently associated with increased risk for anaemia. We also observed a seasonal variation in anaemia not mediated through the other factors studied. Conclusion: In a cohort in rural Bangladesh, anaemia at age 6 months was common and associated with infection, low birthweight and iron deficiency.  相似文献   
29.
The aim of the present work was to investigate the antibacterial, antibiofilm, and antiquorum sensing activities of phytosynthesized silver nanoparticles (AgNPs) fabricated from Mespilus germanica extract against multidrug-resistant (MDR) Klebsiella pneumoniae strains. Fifty strains of K. pneumoniae were isolated from various clinical specimens. Biofilm-forming strains were identified using Congo red agar and polymerase chain reaction (PCR) techniques. Subsequently, the antibacterial activity of phytosynthesized AgNPs on MDR K. pneumoniae strains was investigated by broth microdilution assay and agar well-diffusion method. Finally (in the last step), the antibiofilm activity of phytosynthesized AgNPs was determined using microtiter plate assay and real-time PCR (RT-PCR) methods for the analysis of type 3 fimbriae (mrkA) and quorum-sensing system (luxS) gene expression. The results of this study showed that the phytosynthesized AgNPs had a spherical nanostructure with the mean size of 17.60 nm. The AgNPs exhibited dose-dependent antibacterial activity. The results of the microtiter plate and RT-PCR methods show that AgNPs inhibited the biofilm formation in MDR K. pneumoniae strains, and the expressions of mrkA and luxS genes were downregulated significantly in MDR strains after treatment with a subminimum inhibitory concentration of AgNPs. In conclusion, AgNPs effectively prevent the formation of biofilms and kill bacteria in established biofilms, which suggests that AgNPs might be a promising candidate for the prevention and treatment of biofilm-related infections caused by MDR K. pneumoniae strains.  相似文献   
30.
Cat scratch disease (CSD) is a self limited zoonotic disease that presents most commonly as a regional lymphadenopathy. We are reporting a case of a 25-year-old male patient who presented with fever and large right inguinal lymphadenopathy. The diagnosis of cat scratch disease was confirmed based on the characteristic cytopathological features on aspirate smears from the lymph node and the serological titers for Bartonella henselae. This case report emphasizes the importance of combining Bartonella serology, and cytopathology in the diagnostic work-up of febrile lymphadenopathy and suspected CSD since the culture of this organism is arduous.  相似文献   
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