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81.
Molecular characterization of a mannoprotein with homology to chitin deacetylases that stimulates T cell responses to Cryptococcus neoformans 总被引:3,自引:0,他引:3
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Levitz SM Nong S Mansour MK Huang C Specht CA 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(18):10422-10427
The fungus Cryptococcus neoformans is a major cause of morbidity and mortality in patients with impaired CD4(+) T cell function, particularly those with AIDS. To identify cryptococcal antigens that could serve as vaccine candidates by stimulating T cell responses, C. neoformans-reactive CD4(+) T cell hybridomas were generated by immunization of C57BL/6 mice and fusion of splenocytes with thymoma cells. The antigen that stimulated one of the hybridomas, designated P1D6, to produce IL-2 was purified to homogeneity by sequential anion exchange chromatography, hydrophobic interaction chromatography, and SDS/PAGE. Based on its apparent molecular mass of 98 kDa and mannosylation, the antigen of interest was named MP98. MP98 was N terminal-sequenced, and the gene encoding the protein was cloned and sequenced. Recombinant MP98, expressed in Saccharomyces cerevisiae, stimulated P1D6 to produce IL-2. Analysis of the derived 458-aa sequence of MP98 reveals an N-terminal cleavable signal sequence, a polysaccharide deacetylase domain found in fungal chitin deacetylases, and a serine/threonine-rich C-terminal region. Overall, there were 103 serine/threonine residues serving as potential O-linked glycosylation sites as well as 12 possible N-linked glycosylation sites. Thus, a C. neoformans mannoprotein has been characterized that stimulates T cell responses and has molecular properties of a chitin deacetylase. 相似文献
82.
Severe hypoleptinaemia associated with insulin resistance in patients with common variable immunodeficiency 总被引:1,自引:0,他引:1
Ferraroni NR Geloneze B Mansour E Perroud AP Muscelli EO Tambascia M de Lima Zollner R Velloso LA 《Clinical endocrinology》2005,63(1):63-65
Objective Common variable immunodeficiency (CVI) is a primary immunodeficiency syndrome characterized by impaired production of antibodies and recurrent infections. Delay in diagnosis leads to metabolic wastage and low body weight. Leptin, a hormone produced by white adipose tissue, modulates insulin action by signal transduction cross‐talk and by direct action on pancreatic beta‐cells. We hypothesized that patients with CVI might present a defective regulation of leptin production and insulin resistance. Patients Thirteen CVI patients (39 ± 11 years) under gammaglobulin replacement were evaluated in parallel with 13 gender‐, age‐, body weight‐ and body mass index (BMI)‐matched healthy voluntaries, and with data from two large population series, the Bruneck and the Hoorn Studies. Measurements Serum leptin and insulin levels, homeostasis model assessment – insulin resistance (HOMA‐IR), body composition, haematological, biochemical and immunoglobulin measurements were obtained. Data were analysed by a one‐way analysis of variance (anova ) and by Pearson's rank analysis. The institutional ethics committee approved the study, and informed consent was obtained from patients and controls. Results No differences were found between CVI and the control group when comparing gender distribution, age, body weight, BMI, waist/hip ratio, relative body fat and fasting glucose levels. Leptin levels were lower (P < 0·05) in CVI patients than in controls and lower than fasting leptin levels detected in a large population study. CVI patients’ serum leptin levels did not correlate with BMI (r = 0·074, P = 0·8) and their high HOMA‐IR indicated insulin resistance. Conclusions CVI patients are relatively hypoleptinaemic and insulin resistant, and their serum leptin levels are not correlated to their BMI. 相似文献
83.
Romina Lomonaco Eddison Godinez Leiva Fernando Bril Sulav Shrestha Lydia Mansour Jeff Budd Jessica Portillo Romero Siegfried Schmidt Ku-Lang Chang George Samraj John Malaty Katherine Huber Pierre Bedossa Srilaxmi Kalavalapalli Jonathan Marte Diana Barb Danielle Poulton Nada Fanous Kenneth Cusi 《Diabetes care》2021,44(2):399
OBJECTIVEAssess the prevalence of nonalcoholic fatty liver disease (NAFLD) and of liver fibrosis associated with nonalcoholic steatohepatitis in unselected patients with type 2 diabetes mellitus (T2DM).RESEARCH DESIGN AND METHODSA total of 561 patients with T2DM (age: 60 ± 11 years; BMI: 33.4 ± 6.2 kg/m2; and HbA1c: 7.5 ± 1.8%) attending primary care or endocrinology outpatient clinics and unaware of having NAFLD were recruited. At the visit, volunteers were invited to be screened by elastography for steatosis and fibrosis by controlled attenuation parameter (≥274 dB/m) and liver stiffness measurement (LSM; ≥7.0 kPa), respectively. Secondary causes of liver disease were ruled out. Diagnostic panels for prediction of advanced fibrosis, such as AST-to-platelet ratio index (APRI) and Fibrosis-4 (FIB-4) index, were also measured. A liver biopsy was performed if results were suggestive of fibrosis.RESULTSThe prevalence of steatosis was 70% and of fibrosis 21% (LSM ≥7.0 kPa). Moderate fibrosis (F2: LSM ≥8.2 kPa) was present in 6% and severe fibrosis or cirrhosis (F3–4: LSM ≥9.7 kPa) in 9%, similar to that estimated by FIB-4 and APRI panels. Noninvasive testing was consistent with liver biopsy results. Elevated AST or ALT ≥40 units/L was present in a minority of patients with steatosis (8% and 13%, respectively) or with liver fibrosis (18% and 28%, respectively). This suggests that AST/ALT alone are insufficient as initial screening. However, performance may be enhanced by imaging (e.g., transient elastography) and plasma diagnostic panels (e.g., FIB-4 and APRI).CONCLUSIONSModerate-to-advanced fibrosis (F2 or higher), an established risk factor for cirrhosis and overall mortality, affects at least one out of six (15%) patients with T2DM. These results support the American Diabetes Association guidelines to screen for clinically significant fibrosis in patients with T2DM with steatosis or elevated ALT. 相似文献
84.
Alshihri Abdulmonem A. Al-Askar Mansour H. Aldossary Mohammed S. 《Journal of autism and developmental disorders》2021,51(8):2995-2995
Journal of Autism and Developmental Disorders - In the original publication of the article, the author’s affiliation was processed incorrectly without the name of department. The correct... 相似文献
85.
Dileep R. Yavagal Vasu Saini Violiza Inoa Hannah E. Gardener Sheila O. Martins Manav Fakey Santiago Ortega Ossama Mansour Thomas Leung Fawaz Al-Mufti Ashutosh P. Jadhav Jennifer Potter-Vig Anurag Mairal Miao Zhongrong P.N. Sylaja Andrew M. Demchuk 《Journal of stroke and cerebrovascular diseases》2021,30(8):105806
BackgroundThe COVID-19 pandemic has strained the healthcare systems across the world but its impact on acute stroke care is just being elucidated. We hypothesized a major global impact of COVID-19 not only on stroke volumes but also on various aspects of thrombectomy systems.AimsWe conducted a convenience electronic survey with a 21-item questionnaire aimed to identify the changes in stroke admission volumes and thrombectomy treatment practices seen during a specified time period of the COVID-19 pandemic.MethodsThe survey was designed using Qualtrics software and sent to stroke and neuro-interventional physicians around the world who are part of the Global Executive Committee (GEC) of Mission Thrombectomy 2020, a global coalition under the aegis of Society of Vascular and Interventional Neurology, between April 5th and May 15th, 2020.ResultsThere were 113 responses to the survey across 25 countries with a response rate of 31% among the GEC members. Globally there was a median 33% decrease in stroke admissions and a 25% decrease in mechanical thrombectomy (MT) procedures during the COVID-19 pandemic period until May 15th, 2020 compared to pre-pandemic months. The intubation policy for MT procedures during the pandemic was highly variable across participating centers: 44% preferred intubating all patients, including 25% of centers that changed their policy to preferred-intubation (PI) from preferred non-intubation (PNI). On the other hand, 56% centers preferred not intubating patients undergoing MT, which included 27% centers that changed their policy from PI to PNI. There was no significant difference in rate of COVID-19 infection between PI versus PNI centers (p=0.60) or if intubation policy was changed in either direction (p=1.00). Low-volume (<10 stroke/month) compared with high-volume stroke centers (>20 strokes/month) were less likely to have neurointerventional suite specific written personal protective equipment protocols (74% vs 88%) and if present, these centers were more likely to report them to be inadequate (58% vs 92%).ConclusionOur data provides a comprehensive snapshot of the impact on acute stroke care observed worldwide during the pandemic. Overall, respondents reported decreased stroke admissions as well as decreased cases of MT with no clear preponderance in intubation policy during MT.Data access statementThe corresponding author will consider requests for sharing survey data. The study was exempt from institutional review board approval as it did not involve patient level data. 相似文献
86.
Lamjed Mansour Aouatef Thabet Kalthoum Chourabi Abdul Halim Harrath Mahr Gtari Suliman Y. Al Omar Oum Kalthoum Ben Hassine 《Parasitology research》2013,112(4):1737-1747
A new species Kudoa azevedoi sp. n. (Myxozoa, Multivalvulida) is described in Trachurus trachurus Linnaeus, 1758 (Carangidae) from fishing harbors in Tunisian coasts using spore morphology and SSU rDNA sequence data. The parasite occurs only in ovaries within oocytes of mature and immature specimens. Spores are quadrate in shape in apical view with rounded edges, having four shell valves and four symmetrical polar capsules. They are of small sizes and measure 3.5?±?0.41 (3–4.2)?×?4.5?±?0.44 (4–5.2) length by width. The polar capsules are pyriform in shape measuring 1.5?±?0.22 (1.5–2)?×?0.75?±?0.14 (0.5–1)?μm. Infected oocytes are hypertrophied, whitish colored, and filled with mature spores. Plasmodia are tubular and ramified from the inner membrane toward the center of the oocyte. Phylogenetic analysis based on small subunit ribosomal DNA sequences shows the highest similarity (96 %) with the ovary parasite Kudoa ovivora. Some morphological details and spore dimensions support the creation of a new species in the genus Kudoa. Mean prevalence among examined females is of about 55.5 %. It varies between localities and length of fish. The present myxosporea is the second Kudoa species reported in fish ovaries. 相似文献
87.
Serry A. El Bialy Amira Taman Samar N. El-Beshbishi Basem Mansour Mohamed El-Malky Waleed A. Bayoumi Hassan M. Essa 《Parasitology research》2013,112(12):4221-4229
Currently, praziquantel is the only drug of choice for treatment of schistosomiasis. Reports of praziquantel resistance raise concerns about future control of the disease. Therefore, the search for new schistosomicidal drugs is eminent. In this study, the effect of a novel benzimidazole-derived compound (compound BTP-Iso) was assessed in mice harboring adult Schistosoma mansoni (Egyptian strain). Mice were treated 42 days p.i. with compound BTP-Iso using two treatment regimens (200 or 300 mg/kg). In both regimens, there were significant reductions in the number of recovered S. mansoni worms especially females and in immature ova, in addition to a significant reduction in the number and size of hepatic granulomata. A dose of 300 mg/kg resulted in a significant decrease in intestinal and hepatic tissue egg loads. Effect on schistosomes was confirmed by scanning electron microscopy, where adult worms recovered from mice treated with 200 mg/kg of compound BTP-Iso revealed tegumental alternations, characterised by swelling of tegumental ridges, bleb formation, and mild erosion in male worms; however in females, there were extensive erosion and destruction of the tegumental surface. These promising results may encourage future use of compound BTP-Iso in the treatment of schistosomiasis. However, more research is needed to detect the effect of compound BTP-Iso on early developmental stages of S. mansoni and on other species of human schistosomes. 相似文献
88.
89.
Kristiana Gordon Sarah L. Spiden Fiona C. Connell Glen Brice Sally Cottrell John Short Rohan Taylor Steve Jeffery Peter S. Mortimer Sahar Mansour Pia Ostergaard 《Human mutation》2013,34(1):23-31
Milroy disease (MD) is an autosomal dominantly inherited primary lymphedema. In 1998, the gene locus for MD was mapped to 5q35.3 and variants in the VEGFR3 (FLT4) gene, encoding vascular endothelial growth factor receptor 3 (VEGFR3), were identified as being responsible for the majority of MD cases. Several reports have since been published detailing pathogenic FLT4 mutations. To date, a total of 58 different variants in FLT4, 20 of which are unpublished, have been observed in 95 families with MD. A review of published mutations is presented in this update. Furthermore, the unpublished variants are presented including clinical data. Comparison of clinical features in patients and their families with the same mutations reveals incomplete penetrance and variable expression, making genotype–phenotype correlations difficult. Most mutations are missense, but a few deletions and one splicing variant have also been reported. Several animal models have confirmed the role of VEGFR3 in lymphangiogenesis and studies show mutant VEGFR3 receptors are not phosphorylated. Here, an MD patient with the same p.Ile1053Phe change as seen in the Chy mouse is presented for the first time. This finding confirms that this mouse lineage is an excellent model for MD. All the data reviewed here has been submitted to a database based on the Leiden Open (source) Variation Database (LOVD) and is accessible online at www.lovd.nl/flt4. 相似文献
90.
M.A. Bekadja B. Mansour H. Ouldjeriouat B. Entasoltan S. Bouchama L. Charef K. Amani N. Hakiki F. Bouamama S. Osmani M. Brahimi A. Arabi R. Bouhass N. Yafour 《Transfusion and apheresis science》2021,60(3):103070
Mobilization failure in patients is a major therapeutic concern which makes subsequent ASCT impossible. A new growth factor called Plerixafor (Mozobil®) developed by the pharmaceutical industry (Sanofi-aventis, France), is a chemoreceptor antagonist, CXCR4 type, which disrupts the interaction of SDFI and CXCR4, thereby enhancing the effect of G-CSF mobilization and is especially indicated for mobilization failure. Currently, there is a generic of plerixafor developed by the pharmaceutical industry (Hetero Drugs Ltd, India). The brand name of this medicine is Mozifor®. The objective of this study was to evaluate if generic plerixafor has the same efficacy and safety as originator plerixafor when used with G-CSF in the mobilization of PBSCs for autologous ASCT in multiple myeloma (MM) and lymphoma failure patients. The 32 patients received plerixafor were divided in two groups. The first group concerns the 11 consecutive patients prospectively received generic plerixafor (Mozifor®) in the period between January to July 2020. These were compared with a retrospective control cohort (second group n = 21) who had been treated between 2009 and 2019 with originator plerixafor (Mozobil®). For the Mozifor® group, the mean CD34+ was 4.54x106/kg(1.56-6.79), the median time to achieve an absolute neutrophil count >0.5 G/L was 13 days (range: 8–21). The median time to self-sustained platelet count >20 G/L was 15 days (range: 8–24). For the Mozobil® group, the mean CD34+ was 3.1x106/kg (0.56-8.91) (p=0.86), the median time to achieve an absolute neutrophil count >0.5 G/L was 10 days (range 7–23). The median time to self-sustained platelet count >20 G/L was 13 days (range: 7–29). Our study showed that the generic of plerixafor was practically identical to that of the originator (Mozobil®) with no significant difference (p = 0.52). This study demonstrates the safety and feasibility of mobilization PBSC with generic plerixafor in ASCT in MM and lymphoma. Although these outcomes are encouraging, prospective comparison with other traditional auto-HCT regimens used for patients with MM and lymphoma is warranted. 相似文献