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51.
Eboumbou C Steghens JP Abdallahi OM Mirghani A Gallian P van Kappel A Qurashi A Gharib B De Reggi M 《Acta tropica》2005,94(2):99-106
Epidemiological studies in the developing world are frequently biased by the simultaneous presence of several infectious pathogens. In the present study, we examined the usefulness of circulating markers of oxidative stress and liver fibrosis to investigate the distinct forms of chronic liver inflammations associated with schistosomiasis and viral hepatitis, respectively. The study was performed in a Sudanese population exposed to Schistosoma. Circulating hyaluronic acid (HA) was used as a marker of liver fibrosis; the severity of schistosomiasis was determined by ultrasonic examination; viral hepatitis infection was ascertained by circulating anti-hepatitis antibodies. Serum markers were examined also in Sudanese subjects not exposed to Schistosoma infection and in French control subjects. We found a drastic decrease of lycopene levels in the subjects exposed to schistosomiasis in comparison with non-exposed Sudanese and French control subjects. Retinol, alpha-tocopherol and five carotenoids were unchanged. Lycopene depletion was unlikely to be due to variations of nutritional origin, since the lycopene/beta-carotene ratio was five-fold lower in the population at risk of schistosomiasis than in the other groups. We found that high HA serum levels were associated with severe periportal fibrosis but not with viral infection. Conversely, levels of the oxidized lipid malondialdehyde (MDA) were associated with viral infection but not with the severity of schistosomiasis, even though the two infections had additive effects. We concluded that serum markers are valuable tools for investigating the complex effects of co-existing factors of chronic liver inflammation. 相似文献
52.
The aim of this study was to evaluate the quality of B cell responses in patients with Inflammatory Bowel Disease (IBD) and healthy individuals of different ages, vaccinated with the pandemic (p)2009 influenza vaccine. The in vivo response was measured by the hemagglutination inhibition (HAI) assay, which represents the most established correlate with vaccine protectiveness. The in vitro response was measured by activation-induced cytidine deaminase (AID) in cultures of vaccine-stimulated PBMC. Both responses are somewhat impaired in IBD patients undergoing anti-TNF-α treatment but these are much more decreased in IBD patients undergoing treatment with anti-TNF-α and immunosuppressive (IS) drugs. These latter patients had in vivo and in vitro B cell responses similar to those of elderly individuals. Moreover, as we have previously demonstrated in healthy subjects, the in vitro response to the polyclonal stimulus CpG may be used as a biomarker for subsequent vaccine response and AID activation is correlated with the serum response in IBD patients, as it is in healthy individuals. These results altogether indicate that IBD patients on anti-TNF-α and IS have significantly impaired in vivo and in vitro B cell responses, as compared to those on monotherapy. This is the first report to demonstrate that B cell defects, as measured by the autonomous AID reporter, in IBD patients contribute to reduced humoral responses to the influenza vaccine, as we have previously shown for elderly individuals. 相似文献
53.
Murat Uygun Begüm Akduman Bülent Ergönül Sinan Akgöl Adil Denizli 《Journal of biomaterials science. Polymer edition》2013,24(16):1112-1125
Poly(methyl methacrylate-glycidyl methacrylate) [Poly(MMA-GMA)] cryogels were synthesized using monomers of methylmethacrylic acid and epoxy group bearing GMA via radical cryopolymerization technique. Synthesized cryogels were used for the immobilization of amyloglucosidase to the cryogel surface using epoxy chemistry. Characterizations of the free and immobilized amyloglucosidase were carried out by comparing the optimum and kinetic parameters of enzymes. For this, pH and temperature profiles of free and immobilized preparation were studied and, it was found that, optimum pH of enzyme was not change upon immobilization (pH 5.0), while optimum temperature of the enzyme shifted 10 °C to warmer region after immobilization (optimum temperatures for free and immobilized enzyme were 55 and 65 °C, respectively). Kinetic parameters of free and immobilized enzyme were also investigated and Km values of free and immobilized amyloglucosidase were found to be 2.743 and 0.865 mg/mL, respectively. Vmax of immobilized amyloglucosidase was found to be (0.496 µmol/min) about four times less than that of free enzyme (2.020 µmol/min). Storage and operational stabilities of immobilized amyloglucosidase were also studied and it was showed that immobilized preparation had much more stability than free preparation. In the present work, amyloglucosidase immobilized poly(MMA-GMA) cryogels were used for continuous glucose syrup production from starch for the first time. Efficiency of immobilized enzyme was investigated and released amount of glucose was found to be 2.54 mg/mL at the end of the 5 min of hydrolysis. The results indicate that the epoxy functionalized cryogels offer a good alternative for amyloglucosidase immobilization applications with increased operational and thermal stability, and reusability. Also, these cryogels can be used for immobilization of other industrially valuable enzymes beyond amyloglucosidase. 相似文献
54.
Salman M. Toor Reem Saleh Varun Sasidharan Nair Rowaida Z. Taha Eyad Elkord 《Immunology》2021,162(1):30-43
Coronavirus disease 2019 (COVID‐19) is caused by SARS‐CoV‐2, a novel coronavirus strain. Some studies suggest that COVID‐19 could be an immune‐related disease, and failure of effective immune responses in initial stages of viral infection could contribute to systemic inflammation and tissue damage, leading to worse disease outcomes. T cells can act as a double‐edge sword with both pro‐ and anti‐roles in the progression of COVID‐19. Thus, better understanding of their roles in immune responses to SARS‐CoV‐2 infection is crucial. T cells primarily react to the spike protein on the coronavirus to initiate antiviral immunity; however, T‐cell responses can be suboptimal, impaired or excessive in severe COVID‐19 patients. This review focuses on the multifaceted roles of T cells in COVID‐19 pathogenesis and rationalizes their significance in eliciting appropriate antiviral immune responses in COVID‐19 patients and unexposed individuals. In addition, we summarize the potential therapeutic approaches related to T cells to treat COVID‐19 patients. These include adoptive T‐cell therapies, vaccines activating T‐cell responses, recombinant cytokines, Th1 activators and Th17 blockers, and potential utilization of immune checkpoint inhibitors alone or in combination with anti‐inflammatory drugs to improve antiviral T‐cell responses against SARS‐CoV‐2. 相似文献
55.
Gordana Raca Becky S Baas Salman Kirmani Jennifer J Laffin Craig A Jackson Edythe A Strand Kathy J Jakielski Lawrence D Shriberg 《European journal of human genetics : EJHG》2013,21(4):455-459
We report clinical findings that extend the phenotype of the ∼550 kb 16p11.2 microdeletion syndrome to include a rare, severe, and persistent pediatric speech sound disorder termed Childhood Apraxia of Speech (CAS). CAS is the speech disorder identified in a multigenerational pedigree (‘KE'') in which half of the members have a mutation in FOXP2 that co-segregates with CAS, oromotor apraxia, and low scores on a nonword repetition task. Each of the two patients in the current report completed a 2-h assessment protocol that provided information on their cognitive, language, speech, oral mechanism, motor, and developmental histories and performance. Their histories and standard scores on perceptual and acoustic speech tasks met clinical and research criteria for CAS. Array comparative genomic hybridization analyses identified deletions at chromosome 16p11.2 in each patient. These are the first reported cases with well-characterized CAS in the 16p11.2 syndrome literature and the first report of this microdeletion in CAS genetics research. We discuss implications of findings for issues in both literatures. 相似文献
56.
Lubna Khatoon Muhammad Ishtiaq Jan Inam Ullah Khan Farhat Ullah Salman A. Malik 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2013,58(4):564-569
Malaria is wide spread in poor world and its burden has been assessed by the enumeration of malarial parasites in blood of patients. This study was designed to find a relationship between social structure, and spread of malaria in Khyber agency. The average parasite density was 2050 parasite/μl in Khyber Agency. Due to economic and social setup most of the people have habit of sleeping in open air thus playing role in high malaria prevalence and Plasmodium vivax remains the prevalent species. Genetic study performed on 110 Blood samples showed less genetic diversity for both Plasmodium vivax and Plasmodium falciparum. Eight alleles were distinguished both for Pvmsp 3α and Pvmsp 3β in total of 20 and 39 amplified samples of P. vivax respectively. Out of 17 samples amplified for P. falciparum 11 showed genotype K1 and 10 for MAD at Pfmsp-1 while 14 alleles were identified for 3D7/1C and two for FC27 of corresponding families of Pfmsp-2 gene. This shows that Plasmodium parasites are not genetically diverse in Khyber agency. 相似文献
57.
Yesim Cekin Ayhan Hilmi Cekin Adil Duman Ustun Yilmaz Bayram Yesil Basak Oguz Yolcular 《International journal of medical sciences》2013,10(10):1367-1374
Objective: To determine the role of serum procalcitonin levels in predicting ascites infection in hospitalized cirrhotic and non-cirrhotic patients.Methods: A total of 101 patients (mean age: 63.4±1.3, 66.3% were males) hospitalized due to cirrhosis (n=88) or malignancy related (n=13) ascites were included in this study. Spontaneous bacterial peritonitis (SBP, 19.8%), culture-negative SBP (38.6%), bacterascites (4.9%), sterile ascites (23.8%) and malign ascites (12.9%) groups were compared in terms of procalcitonin levels in predicting ascites infection. Receiver operating characteristic (ROC) curves were used to evaluate the diagnostic performance of procalcitonin levels and predicting outcome of procalcitonin levels was compared with C-reactive protein (CRP).Results: Culture positivity was determined in 26.7% of overall population. Serum procalcitonin levels were determined to be significantly higher in patients with positive bacterial culture in ascitic fluid compared to patients without culture positivity (median (min-max): 4.1 (0.2-36.4) vs. 0.4 (0.04-15.8), p<0.001). Using ROC analysis, a serum procalcitonin level of <0.61 ng/mL in SBP (area under curve (AUC): 0.981, CI 95%: 0.000-1.000, p<0.001), <0.225 ng/mL in culture-negative SBP (AUC: 0.743, CI 95%: 0.619-0.867, p<0.001), <0.42 ng/mL in SBP and culture-negative SBP patients (AUC: 0.824, CI 95%: 0.732-0.916, p<0.001), and <1.12 ng/mL in bacterascites (AUC: 0.837, CI 95%: 0.000-1.000, p=0.019) were determined to accurately rule out the diagnosis of bacterial peritonitis. Predictive power of serum procalcitonin levels in SBP + culture-negative SBP group (AUCs: 0.824 vs 0.622, p=0.004, Fig 4), culture-positive SBP (AUCs: 0.981 vs 0.777, p=0.006, Fig 5) and (although less powerfull) in culture-negative SBP (AUCs: 0.743 vs 0.543, p=0.02, Fig 6) were found significantly higher than CRP.Conclusion: According to our findings determination of serum procalcitonin levels seems to provide satisfactory diagnostic accuracy in differentiating bacterial infections in hospitalized patients with liver cirrhosis related ascites. 相似文献
58.
59.
Murat Cakir Ahmet Tekin Tevfik Kucukkartallar Husamettin Vatansev Adil Kartal 《International surgery》2015,100(5):897-902
Multiple organ failure and pancreatic necrosis are the factors that determine prognosis in acute pancreatitis attacks. We investigated the effects of collagenase on the debridement of experimental pancreatic necrosis. The study covered 4 groups; each group had 10 rats. Group I was the necrotizing pancreatitis group. Group II was the collagenase group with pancreatic loge by isotonic irrigation following necrotizing pancreatitis. Group III was the collagenase group with pancreatic loge following necrotizing pancreatitis. Group IV was the intraperitoneal collagenase group following necrotizing pancreatitis. The progress of the groups was compared hematologically and histopathologically. There was no difference among the groups regarding the levels of leukocyte, hemogram, and urea. The differences in AST levels between Group I and II; and differences in glucose, calcium, LDH, AST, and amylase between Group II and III; between Group II and IV; between Group I and III; and between Group I and IV were statistically significant (P < 0.05). There were statistically significant differences between Group II and III, and Group II and IV regarding edema, acinar necrosis, inflammatory cell infiltration, hemorrhage, and fat necrosis (P < 0.05). In conclusion, the collagenase preparation used in this experimental pancreatitis model was found to be effective in the debridement of pancreatic necrosis.Key words: Acute pancreatitis, Necrose, Collagenase, DebridementAcute pancreatitis (AP) is a nonbacterial inflammatory disease of the pancreas that can range from interstitial edema to pancreatic necrosis in its severest form. In about 20% of AP attacks necrosis can develop in the pancreas while the disease limits itself and regresses in a couple of days in many patients (80%).1The definitions that are still widely in effect today regarding the classification of acute pancreatitis were determined in 1992 at the Atlanta Conference.2 The conference aimed at achieving a common classification for AP and its complications. Within severe acute pancreatitis, of which necrotizing pancreatitis is a part, organ failure and local complications can be seen (necrosis, pseudocyst, and abscess). Multiple organ failure and pancreatic necrosis are the factors that determine the prognosis. Half of the mortalities are observed within a period of 1 or 2 weeks. Necrotizing pancreatitis makes up for the 10–20% of AP cases. Severe pancreatitis has a high mortality rate and functional diseases like diabetes are seen in one-third to one-fifth of the recovered patients.3While the mortality rates are about 10% in the presence of sterile pancreatic necrosis, they go up over 30% in the existence of infected necrosis.1 Regarding acute necrotizing pancreatitis, there is still no consensus on surgical indications and the time of surgical intervention, the surgical method to be used, and which patients need conservative treatment and which ones need surgical treatment. The goal in the surgical treatment of acute necrotizing pancreatitis is to isolate the necrotic tissue that might cause sepsis and multiple organ failure and to reduce the risk of mortality. The timing of necrosectomy as well as the way in which necrosectomy is performed is significant in necrotizing pancreatitis. The issue of the possibility that necrosectomy can be performed through minimally-invasive interventions instead of open surgery is still being discussed.3We planned to investigate the activity of collagenase clostridiopeptidase A (EC 3.424.3), which has never been attempted before in the debridement of experimental pancreatic necrosis (but which has been used for enzymatic debridement), and the enzyme preparation containing the accompanying proteases (Sterile Novuxol®, Abbott, Uetersen, Germany). We aimed to evaluate the response of the disease to treatment through laboratory and histopathologic data, by using the enzyme preparation to treat necrotizing pancreatitis. 相似文献
60.