المقالات العلمية – كلية الطب
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Item Item Analysis of T-cell responses in malaria-exposed and non-exposed donors using Plasmodium falciparum asexual blood stages enriched by a simple centrifugation method(Elsevier, 2006-01-31) Ahmed Bolad, Salah E Farouk; Jinfeng Shen, Klavs Berzins; Marita Troye-BlombergSeveral studies have reported on similar in vitro cellular responses to different malaria-antigen preparations in both malaria-primed and un-primed donors. Whether intact live parasites can exert a distinct type of response in either of the two groups is not well known. In this study, we developed a simple three-step centrifugation method for simultaneous enrichment of early and late blood stages from Plasmodium falciparum cultures. Such enriched P. falciparum fractions and other antigen preparations were used to stimulate lymphocytes from malaria-exposed and non-exposed individuals to examine the proliferative activity and expansion of CD3+, γδ+, CD4+, and CD8+ T cells. While lymphocytes from malaria non-exposed donors proliferated relatively higher than those from malaria-exposed donors in response to most antigens tested, the enriched fractions of live parasites exerted higher proliferative responses on cells from the latter donors. This suggests the existence of memory cells in the malaria-exposed donors, but not in the non-exposed ones. Flow cytometric analysis revealed a higher percentage expansion of CD4+ T cells in the responding cells of the exposed donors than the non-exposed ones. Taken together, this study reports on a simple method that simultaneously enriches for intact live early and late blood stages of P. falciparum parasites. Moreover, the study revealed higher expansion CD4+ T cells in the exposed individuals than the non-exposed in response to live malaria parasites and not to other parasite–antigen preparations.Item Antibodies to the Plasmodium falciparum antigen Pf332 inhibit parasite growth in vitro on their own and in cooperation with monocytes(Wenner-Grens institut för experimentell biologi, 2004) AK Bolad, L Xu; K BerzinsProtective immunity against Plasmodium falciparum may be obtained after repeated exposure to infection. Several studies indicate that immunity against the blood stages of the P. Falciparum infection is mainly antibody mediated. Protective antibodies may act either on their own, mediate antibody-dependent phagocytosis and/or cell-mediated neutralization of parasites. This thesis describes several aspects of humoral immune responses to P. falciparum infection in individuals of different age groups, different genetic background and with different degrees of malaria exposure. Several target antigens for antibody-mediated inhibition of parasite growth or invasion have been identified. One such antigen is Pf332, which appears on the surface of parasitized erythrocytes at late trophozoite and schizont stage. This surface exposure makes the antigen a possible target for opsonizing antibodies. We optimized an in vitro assay for studying cellmediated parasite neutralization in the presence of Pf332-reactive antibodies. Our data demonstrate that, Pf332 specific antibodies are able to inhibit parasite growth on their own and in cooperation with human monocytes. The P. falciparum parasites have evolved several mechanisms to evade the host neutralizing immune responses. In this thesis, we show that freshly isolated P. falciparum parasites from children living in a malaria endemic area of Burkina Faso were less sensitive for growth inhibition in vitro by autologous immunoglobulins (Ig) compared with heterologous ones. Analyses of two consecutive isolates taken 14 days apart, with regard to genotypes and sensitivity to growth inhibition in vitro, did not give any clear-cut indications on possible mechanisms leading to a reduced inhibitory activity in autologous parasite/antibody combinations. The frequent presence of persisting parasite clones in asymptomatic children indicates that the parasite possesses as yet undefined mechanisms to evade neutralizing immune responses. Transmission reducing measures such insecticide treated nets (ITNs) have been shown to be effective in reducing morbidity and mortality from malaria. However, concerns have been raised that ITNs usage could affect the acquisition of malaria immunity. We studied the effect of the use of insecticide treated curtains (ITC) on anti-malarial immune responses of children living in villages with ITC since birth. The use of ITC did neither affect the levels of parasite neutralizing immune responses nor the multiplicity of infection. These results indicate that the use of ITC does not interfere with the acquisition of anti-malarial immunity in children living in a malaria hyperendemic area. There is substantial evidence that the African Fulani tribe is markedly less susceptible to malaria infection compared to other sympatrically living ethnic tribes. We investigated the isotypic humoral responses against P. falciparum asexual blood stages in different ethnic groups living in sympatry in two countries exhibiting different malaria transmission intensities, Burkina Faso and Mali. We observed higher levels of the total malaria-specific-IgG and its cytophilic subclasses in individuals of the Fulani tribe as compared to non-Fulani individuals. Fulani individuals also showed higher levels of antibodies to measles antigen, indicating that the intertribal differences are not specific for malaria and might reflect a generally activated immune system in the Fulani.Item Antibodies to the Plasmodiumfalciparum antigen Pf332 cooperated with human monocytes inhibit parasitegrowth by inducing intraerythrocytic abnormal parasite forms in vitro(2013) Lili Xu, Ahmed Bolad; Nina-Maria Vasconcelo, Nancy Awah; Asok Chaudhuri, Klavs BerzinsIntraerythrocyticPlasmodium parasite proliferation istightly related to disease seriousness. Intraerythrocytic parasite developmentis fundamental to the proliferation of the malaria parasite which is affectedby many factors. Antibodies inhibiting intraerythrocytic parasite growth ordevelopment have been long indicated in protective immune mechanisms, particularly in cooperation with human monocytes. Here, we show that the developmentP. falciparum intraerythrocyticparasite was significantly disturbed by antibodies reactive with ...Item Antibody responses in Plasmodium falciparum malaria and their relation to protection against the disease(Wenner-Grens institut för experimentell biologi, 2004) Ahmed Kamal BoladProtective immunity against Plasmodium falciparum may be obtained after repeated exposure to infection. Several studies indicate that immunity against the blood stages of the P. Falciparum infection is mainly antibody mediated. Protective antibodies may act either on their own, mediate antibody-dependent phagocytosis and/or cell-mediated neutralization of parasites. This thesis describes several aspects of humoral immune responses to P. falciparum infection in individuals of different age groups, different genetic background and with different degrees of malaria exposure. Several target antigens for antibody-mediated inhibition of parasite growth or invasion have been identified. One such antigen is Pf332, which appears on the surface of parasitized erythrocytes at late trophozoite and schizont stage. This surface exposure makes the antigen a possible target for opsonizing antibodies. We optimized an in vitro assay for studying cellmediated parasite neutralization in the presence of Pf332-reactive antibodies. Our data demonstrate that, Pf332 specific antibodies are able to inhibit parasite growth on their own and in cooperation with human monocytes. The P. falciparum parasites have evolved several mechanisms to evade the host neutralizing immune responses. In this thesis, we show that freshly isolated P. falciparum parasites from children living in a malaria endemic area of Burkina Faso were less sensitive for growth inhibition in vitro by autologous immunoglobulins (Ig) compared with heterologous ones. Analyses of two consecutive isolates taken 14 days apart, with regard to genotypes and sensitivity to growth inhibition in vitro, did not give any clear-cut indications on possible mechanisms leading to a reduced inhibitory activity in autologous parasite/antibody combinations. The frequent presence of persisting parasite clones in asymptomatic children indicates that the parasite possesses as yet undefined mechanisms to evade neutralizing immune responses. Transmission reducing measures such insecticide treated nets (ITNs) have been shown to be effective in reducing morbidity and mortality from malaria. However, concerns have been raised that ITNs usage could affect the acquisition of malaria immunity. We studied the effect of the use of insecticide treated curtains (ITC) on anti-malarial immune responses of children living in villages with ITC since birth. The use of ITC did neither affect the levels of parasite neutralizing immune responses nor the multiplicity of infection. These results indicate that the use of ITC does not interfere with the acquisition of anti-malarial immunity in children living in a malaria hyperendemic area. There is substantial evidence that the African Fulani tribe is markedly less susceptible to malaria infection compared to other sympatrically living ethnic tribes. We investigated the isotypic humoral responses against P. falciparum asexual blood stages in different ethnic groups living in sympatry in two countries exhibiting different malaria transmission intensities, Burkina Faso and Mali. We observed higher levels of the total malaria-specific-IgG and its cytophilic subclasses in individuals of the Fulani tribe as compared to non-Fulani individuals. Fulani individuals also showed higher levels of antibodies to measles antigen, indicating that the intertribal differences are not specific for malaria and might reflect a generally activated immune system in the Fulani.Item Antibody-mediated in vitro growth inhibition of field isolates of Plasmodium falciparum from asymptomatic children in Burkina Faso(The American Society of Tropical Medicine and Hygiene, 2003-06-01) Ahmed BoladAntibody-mediated inhibition of Plasmodium falciparum parasites in vitro reflects the potential parasite-neutralizing activity of the antibodies in vivo. In this study, immunoglobulins and P. falciparum isolates were collected from children with asymptomatic malaria in Burkina Faso. We demonstrate a significantly lower in vitro growth inhibitory activity against the P. falciparum field isolates by autologous host immunoglobulin compared with that of immunoglobulin from other individuals. To gain further insight to possible ...Item Antigenic diversity of Plasmodium falciparum and antibody-mediated parasite neutralization(Blackwell Scientific Publications, 1972) A Bolad, K BerzinsAbstract The malaria parasite Plasmodium falciparum, causing the most severe form of the disease in humans, is characterized by a broad antigenic diversity between different strains and isolates of the parasite. The antigenic diversity reflects on the one hand polymorphisms in allelic gene products and, on the other hand, antigenic variation as a result of expression of alternative genes in multigene families. Using selected polymorphic regions in two merozoite surface antigens, a method for genotyping P. falciparum parasites has been ...Item Antiplasmodial activity of seven plants used in African folk medicine(Medknow Publications on behalf of Indian Pharmacological Society, 2004) Ahmed Bolad, G Bidla; VPK Titanji, B Joko; G El-Ghazali, K BerzinsResults are expressed as mean+ SD. The differences between experimental groups were compared by one-way ANOVA (control Vs treatment) followed by Student-Neuman-Keuls test and were considered statistically significant at P< 0.05. The number of acetic acid induced writhings were significantly reduced by treatment with AO-1 in both the doses. The effect was found to be more than that of the standard, diclofenac (20 mg/kg) at a dose of 100 mg/kg (Table 1). AO-1 pretreatment significantly reduced the paw edema in rats. The effect ...Item Assessment of Nurse’s Competences during Emergency Management of patients with Acute Myocardial Infarction at critical care units and emergency department at Public Teaching Hospitals in Khartoum State (2013(جامعة النيلين-مركز النيلين الطبي, 2013) Ahmed Bolad, Hassanat Elbashir Mohamed Mustafa,; Mustafa Nimeiri, Siddig KhalilThe aim of this study was to assess the knowledge, attitude and skill of the nurses whom work at CCU and emergency department (EM) in 2012. The standardized administered questionnaire was used for data collection. The level of knowledge of 139 nurses working at the critical care units and emergency department at Public Teaching Hospitals in Khartoum State was assessed. The data was processed using the statistical package software (SPSS); version 19. For the analysis, Chi-Square test was used, P-value <0.05 was considered statistically significant. Results showed that 32% of study population had very poor level of knowledge, while 44% had poor level whereas 12% had a good level. 42% had good knowledge about acute coronary syndrome’s components while 10% were at poor level and 16.5% were at very poor level. In the same manner half of them their knowledge about initial management of acute myocardium infarction was poor level, while (21%) had good knowledge.. Also the study population knowledge’s about arrhythmias that occur at initial phase was very poor (39.6%), poor (27.3%) and there was no one at a good level, Lastly their knowledge about the factors which lead to delay of emergency management of AMI was (40.3%) at poor level, (27.3%) at very poor while only (5.8%) at good level.Item Association between diabetes mellitus type 1 and celiac disease: case-control study among Sudanese patients 2009-2011(Omdurman Islamic University, 2012) Ahmed Bolad, Ahmed Farouk; Mohamed Faisal Lutfi, Mustafa NemeiriBackground: Gluten sensitive enteropathy (celiac disease (CD)) has a strong association with diabetes mellitus (type 1DM). Since, 2-3% of CD patients have selective IgA deficiency, the majority of the available tests may fail to show the auto-antibodies (the IgA endomysial antibody (EMA). To prevent such a false negativity, a new Enzyme Linked Immune Sorbent Assay (ELISA) test has been introduced to detect both IgG and IgA antibodies reactive with tissue transglutaminase (tTG), an autoantigen in CD patients. Objectives: This study has been conducted to detect celiac disease among Sudanese patients with type 1 autoimmune diabetes using anti-tissue transglutinamase antibodies as a diagnostic tool. Patients and Methods: Samples were collected from sixty nine randomly selected patients (38 males and 31 females) and their age ranged between 3-22 years with DM type 1 who were attending the outpatient clinics in Gabir Abu Eliz diabetic Center and Omdurman Pediatric Emergency Hospital. Blood samples were collected from 25 healthy individuals as controls. Levels of tTG specific IgA, tTG specific IgG and anti-endomysial antibodies of IgA class were measured in sera collected from both cases and from controls. All the results were analyzed using Statistical Packages of Social Sciences (SPSS) version 17 and MicroSoft office excel. Results: Seven out of 69 patients with DM type 1 (10.1%) were identified as having CD using IgG anti-tTG and 5 (7.2%) of them were positive for IgA anti-tTG and IgA anti-endomysial antibodies. The mean of both anti-tTG IgA and IgG titers were higher in diabetic patients (M±SD = 12.30±41.0 and 7.2±13.1 respectively) when compared with the control group (M±SD =1.8±1.1 and 1.8±0.9 respectively), however, only anti-tTG IgG antibodies titer achieved statistical significance. Discussion and conclusion: The present study revealed that patients with DM type I have an increased tendency to develop CD. The increased association of CD and selective IgA deficiency is a potential source of false-negative IgA, therefore testing for IgG class autoantibodies is recommended if celiac disease is suspected. Antibodies to tTG antigen fall once a gluten-free diet has begun, thus facilitating monitoring of dietary compliance. Thus, anti-tTG antibodies are highly sensitive marker for celiac disease with 95- 100 % sensitivty, and specificity of 90 to 97 %.Item Association between H. Pylori and Urticaria or Gastritis(مركز النيلين الطبي, 2015) Ahmed Bolad, Sheema Mohsin Mustafa; Maha Ibrahim, Tarig Abbas; Alsagad AltayebBackground: Studies have established that Helicobacter pylori can cause chronic gastritis. Recent evidence suggests that Helicobacter pylori infections play a great role in the pathogenesis of a variety of skin diseases, the best evidence for such a link is found for two diseases; chronic urticaria and immune thrombocytopenic purpura. Objectives: the current study is aiming at evaluating the relationship between H. pylori among patients with different cutaneous problems mainly chronic urticaria by using immunological methods. On the other hand the study is aiming at verifying the effect of treatment on the prevalence of disease. Materials and Methods: 119 Specimens (blood and stool samples) were obtained. Serum was stored at -20°C until used. Stool was collected in clean container and tested immediately. Specimens were processed by Serum ICT (ACCURATE, diagnostic use, china) and Stool Antigen ICT KITS (CERTEST BIOTEC S.L.) for detection of H. pylori. Significance tests, measures of accuracy and confidence intervals were calculated using the biomedical Stats Direct Statistical Software v2.7.9 (7/9/2012). IBM SPSS Statistics v22 was used in the descriptive data analysis. Results and discussion: H. Pylori infection was detected in about half of the patients who suffered from either urticaria or gastritis. The prevalence of H. Pylori was estimated in the three groups as 48.3% (CI: 35.2% to 61.6%); in the urticaria group, 51.7% (CI: 32.5% to 70.6%); in the gastritis group and 13.3% (CI: 3.8% to 30.7%) in the apparently healthy group (labelled ‘Normal’). Proportions of H. Pylori infection in the urticaria and the gastritis groups were not NMJ June 2015 vol.3 No.16 ISSN 1858-6155 NMJ 2015 statistically significantly different. Both groups, however, had a significantly different proportion of HP infected patients when compared with the apparently healthy (Normal) group. This statistically significant difference was suggestive of an association between H. Pylori and both of urticaria and gastritis.Item Clarithromycin-Resistant Helicobacter Pylori Strains among Dyspeptic Patients in Sudan(Al-Neelain Medical Research Centre, 2012) Ahmed Bolad, Nazar Abdalazeem; Hassan Abdul-Aziz, Adam Ahmed Adam; Waleed Hussein OmerIntroduction: The study aimed at characterizing the mutations in 23S rRNA gene related to Clarithromycin-resistant Helicobacter pylori strains among dyspeptic patients in Khartoum State. Methods: Two hundred gastric biopsies were obtained by endoscopy from 200 patients with dyspepsia. DNA was extracted from culture isolated and relevant mutations in 23S rRNA gene were detected. Results: Out of the 200 biopsies, H. pylori was isolated from 48 (24%) biopsies. Twelve of them were found to be resistant to Clarithromycin. Eight of the resistant strains had both A2143G and A2142G by using restriction enzymes Bsa1and Bbs1. Sequencing the remaining four isolates by PCR detected A2140G mutation. Conclusions: In conclusion, Clarithromycin-resistant H. pylori in Sudan may be the main cause of treatment failure aiming at eradication of the bacterium from patients. Such a finding may necessitate the need for other treatment regimens. More collaborated research in this field is needed.Item The clinical importance of anti-CCP in early diagnosis of Sudanese patients with rheumatoid arthritis(2015) Ahmed Kamal BoladBackground: Rheumatoid Arthritis (RA) is a systemic inflammatory autoimmune disorder; it is the most common inflammatory arthritis in the world. The early diagnosis and effective treatment of rheumatoid arthritis (RA) can improve the clinical outcome of the disease. Recently, anti-Cyclic-Citrullinated protein antibodies (Anti-CCP) are found to be more specific to RA arthritis although in the early stages when the arthritis is undifferentiated. The objective of this study was to determine the clinical importance and the prevalence of anti-CCP in early diagnosis of Sudanese patients with RA. Methodology This work was a cross-sectional study conducted at Al Ribat teaching hospital (from June 2012 to ? 2014). The study sample included 56 Sudanese patients, known patients of RA who fulfilled the ACR criteria. Demographic and clinical data were collected by questionnaires. All patients and controls sera were investigated for anti-CPP by enzyme linked immunosorbent assay (ELISA). Results The mean age of RA patients in this study was 46.0 (±11.7) years. The control group consisted of 56 Sudanese apparently healthy subjects, 27 (48%) of them were female with mean age of 37 ±17.2years. The anti-CCP antibodies were detected in 60.7% of cases, and in two (3.6%) of the control group. The sensitivity of anti-CCP was 60.7% and specificity of 96.4%. Anti-CCP test has a maximum proportionate reduction in uncertainty (PRU) of 94% for a positive result and 59% for a negative result. Conclusions Anti-CCP antibody has a higher diagnostic specificity and positive predictive value than rheumatoid factor; however its sensitivity was low. The clinical importance of anti-CCP in early diagnosis of Sudanese patients with rheumatoid arthritis (PDF Download Available). Available from: https://www.researchgate.net/publication/286931967_The_clinical_importance_of_anti-CCP_in_early_diagnosis_of_Sudanese_patients_with_rheumatoid_arthritis [accessed Sep 26, 2017].Item Comparison of different diagnostic methods of Helicobacter pylori infection in Sudanese patients(Alneelain University, 2012) Ahmed Kamal Bolad, Nazar Abdalazeem Osman Abdalsadeg; Adam Ahmed Adam, Hassan Abdul-Aziz; Waleed Hussein Omer, Hassan Abdalsalam OsmanThis study aimed at comparing a PCR method of direct detection from biopsy and two other methods: culture and (campylobacter like organism) CLO test for the diagnosis of H. pylori in Sudan. A total of 100 biopsies were taken from 100 patients presenting with various gastroduodenal symptoms after obtaining an informed consent. The biopsies were analyzed using the culture method, CLO test kit and the PCR test using the 23S rRNA gene (Jene bioscience kits). With culture 48% (48 out of 100) were positive, CLO test 53% (53 of 100) were positive, 58 out of 100(58%) were patients by using PCR. Sensitivity and specificity of culture technique was (78%) and (94%) respectively while PCR showed a sensitivity of 94% and a specificity of 75% and CLO test showed (96% & 86.5%) for sensitivity and specificity when culture was the golden method and (88%, 95%) when PCR was the golden method. The PCR test appears to be the most reliable test for diagnosis of H. pylori in Sudan especially where culture is difficult.Item Comparison of Rheumatoid Factor and anti-Cyclic-Citrullinated protein antibodies for the Diagnosis of rheumatic arthritis in Khartoum, Sudan(Al Neelain Medical Research Centre, 2008) Ahmed Bolad, Shaaban Khudair; Mohammed Abbas, Mowahib Al EdressyBackground: The objective of the current study was to determine the sensitivity and specificity of anti-Cyclic-Citrullinated protein antibodies (anti-CCP antibodies) as compared to that of Rheumatoid Factor (RF) in diagnosing patients with rheumatoid arthritis (RA) Methodology Fifty six samples were collected from Sudanese patients (46 females, 9 males) with rheumatic diseases who visited the rheumatology clinic ElRibat Hospital, Khartoum, Sudan. Titers of RF and anti-CCP antibodies of each patient were recorded. Sensitivity and specificity of the test were evaluated using ELISA as the gold standard method. Results The sensitivity of (RF) test (41/56) was 73.2% whereas the sensitivity of Anti CCP test (34/56) was 60.7%. The specificity of RF test (44/56) was 78.6%, whereas the specificity of Anti CCP test (54/56) was 96.4%. Conclusions The combination of anti-CCP and RF tests provides nearly 100% and thus could be helpful in the differential diagnosis of RA and other rheumatic diseases Comparison of Rheumatoid Factor and anti-Cyclic-Citrullinated protein antibodies for the Diagnosis of rheumatic arthritis in Khartoum, Sudan. Available from: https://www.researchgate.net/publication/271014292_Comparison_of_Rheumatoid_Factor_and_anti-Cyclic-Citrullinated_protein_antibodies_for_the_Diagnosis_of_rheumatic_arthritis_in_Khartoum_Sudan [accessed Oct 08 2017].Item Construction, expression and characterisation of a single chain variable fragment in the Escherichia coli periplasmic that recognise MCF-7 breast cancer cell line(Medknow Publications, 2014-04-01) Ahmed Kamal Bolad, Elham Omer MahgoubBackground: A functional single-chain fragment variable (scFv) recognizing the MCF-7 breast cancer carcinoma cell line was constructed from the C3A8 hybridoma using phage display technology. Aim of Study: This study was conducted to evaluate the binding activity of scFv antibody recognise MCF-7 breast cancer cells carcinoma, the scfv antibody constructed and expressed in Escherichia coli periplasmic. Materials and Methods: The scFv coding sequence was cloned in frame with the pIII phage coat protein. The signal sequence included in the C terminus directed the expression of the scFv in the Escherichia coli periplasm. Following several rounds of biopanning, colonies that expressed a scFv that recognized MCF-7 cells in Western blots, ELISAs, and flow cytometry test were isolated. Results: A 750-bp scFv gene was successfully isolated. Cloning and two rounds of biopanning isolated the candidate with the highest activity (clone B7), as screened by ELISA. Following poly-acrylamide gel electrophoresis (SDS-PAGE) of the purified product, a 32-kDa band was observed. A similar-sized band was observed following Western blot analysis with an E tag-specific antibody. Binding reactivity of scFv antibody with MCF cells was determined using indirect ELISA and compared with monoclonal antibodies' reactivity. Also, flow cytometry was useful in further characterization to the binding reactivity of scFv antibody with MCF-7 cells. Conclusions: The recombinant antibody technology used in this study is a rapid and effective approach that will aid in the development of the next generation of immunodiagnostic reagents.Item Correctness and accuracy of template-based modeled single chain fragment variable (scFv) protein anti-breast cancer cell line (MCF-7)(Scientific Research Publishing, 2013-08-01) Ahmed Bolad, Elham O MahgoubMultiple sequence alignments can be used in the tem- plate-based modelling of protein structures to build fragment-based assembly models. Therefore, useful functional information on the 3D structure of the anti-MCF-7 scFv protein can be obtained using available bioinformatics tools. This paper utilises several commonly-used bioinformatics tools and da- tabases, including BLAST (Basic Local Alignment Search Tool), GenBank, PDB (Protein Data Bank), KABAT numbering and SWISS-MODEL, to gain specific functional insights into the anti-MCF-7 scFv protein and the assembly of single-chain fragment variable (scFv) antibodies, which consist of a variable heavy chain (VH) and a variable light chain (VL) connected by the linker (Gly4-Ser)3. The linker has been built as a loop structure using the Insight II software. The accuracy of the loop structure has been evaluated using Root Mean Square Deviation (RMSD). The accuracies of the VL and VH tem- plate-based structures are enhanced by using the evaluation methods Verify3D, ERRAT and Ram- chandran plotting, which measure the error in the residues. In the results, 100% of the light-chain resi- dues scored above 0.2, whereas 88.5% of the heavy- chain residues’ scored above 0.15 in the Verify3D evaluation method. Meanwhile, using ERRAT, the alignments of both chains scored more than 70% in space. Additionally, the Ramchandran plot evalua- tion method showed large numbers of residues in the favoured areas in both chains; these findings demon- strated that all of the chosen templates were the best candidates.Item Culturing of erythrocytic asexual stages of Plasmodium falciparum and P. vivax(Methods in malaria research, 2008) Fingani Mphande, Sandra Nilsson; Ahmed BoladComment: For growing parasites from patient blood, use 10 g of Albumax for 1 liter of complete MCM. The vast majority of cultures will survive at least 2 weeks. It is also important to avoid serum in the culture for preparation of crude parasite antigen (see SEROLOGY, section III: B). Not all strains can be adopted to Albumax II medium.Item Cytokines as Immunological Markers for Follow up of Disease Activity During the Treatment of Pulmonary Tuberculosis(Omdurman Islamic University, 2012) A Bolad, A Elhaj, A ElagibBackground: Cytokines play a major role in protection against Mycobacterium tuberculosis infection and regulate the immune responses at a cellular level. Cytokine profile determines clinical outcome of the disease and responses to treatment as well. A T helper 1 (Th1) cytokine interferon gamma (IFN-U) is one of the most important cytokines which activate the macrophages to produce tumor necrosis factor-alpha (TNF-V). Excessive production of TNF-V have been implicated in immunopathogenesis of tuberculosis. A T helper 2 (Th2) response leads to release of IL-4, and IL-10 promoting an anti-inflammatory macrophage response. Interleukin-4(IL-4), has been implicated to down-regulate IFN-U, and thus has a harmful effect on TB patients. IL10 cytokine has the capacity to inhibit Th1 activation and thus terminates cell mediated immune responses. Objective:The objective of the present study was to determine Th1 and Th2 cytokine profile in patients with tuberculosis to identify immunological marker for follow up of the disease activity, and to study the outcome of treatment. Methods: To examine this, blood samples were collected from newly diagnosed HIV negative pulmonary tuberculosis patients and from apparently healthy individuals as controls following an informed consent. Blood samples were as well collected at several intervals during the treatment with anti-tuberculosis drugs. Levels of IFN-U, TNF-V, IL-4 and IL-10 were measured pre and during treatment using commercial available enzyme-linked immune-sorbent assay (ELISA). Data were analyzed using SPSS 20. Receiver Operating Characteristic (ROC) Curve analysis has been carried out to assess their discriminative power and to determine cut-off values. Analysis has been carried out further by calculating other measures of diagnostic test accuracy. Results: The median serum level of IL-4 was 20 and 35 pg/ml higher in new cases (untreated patients) and in patients under treatment with oral anti-tuberculosis, respectively, compared with that of controls (p=001). Levels of TNF- were significantly increased in patients before and after the treatment than those in control (p=0.001). New cases had the highest median level (10pg/ml) followed by those under treatment group (6pg/ml). Levels for IFN-U were not statistically different between patients and controls (p=0.351). Median levels of IL10 were similar in both controls and new cases groups (35pg/ml), but lower in patients under treatment group (20pg/ml). Increase in levels of IL-4 during treatment showed that Th2 immune responses still present and may indicate active disease and thus IL4 cytokine may be a possible marker for the disease activity. Conclusion: serum levels of TNF- in TB patients is useful in the evaluation of the disease activity during therapy, not replacing clinical parameters of disease activity in TB. Similar to TNF-, IL-4 can also be used as marker for TB severity. On the other hand IL-4test can be used to diagnose TB in highly exposed suspects where a positive result is more likely to indicate TB.Item Detection of Helicobacter pylori Reactive IgA and IgG Antibodies Using Enzyme Linked Immunsorbent Assay (ELISA)(Sudanese Association of Dermatologists, 2010) Ahmed Bolad, Samah Seif Eldein; Mohamed LutfiBackground: Helicobacter pylori (H. pylori) infection is usually acquiredduring the early years of life and persists for several years. Recent investigations pointed to a potential role of H. pylori infection of the upper gastrointestinal tract as a possible causative agent in chronic urticaria (CU).Objectives: This study is aiming at evaluating the relationship between H. pylori and chronic urticaria in Sudanese patients.Methods and patients: Fifty patients with idiopathic CU, twenty five ofother skin disorder and ten healthy controls were enrolled estimated for serum H.pylori Immunoglobulin G (IgG) and A (IgA) antibodies levels using Enzyme Linked Immunsorbent Assay (ELISA). All the results were analyzed using the Microsoft Office Excel (Microsoft Office Excel for windows; 2003) and SPSS (SPSS for windows 17).Results and discussion: The IgG and IgA levels of control group weresignificantly lower compared with both patients with chronic urticaria (P = 0.001 for IgG) (P = 0.001 for IgA) and patients with other skin disorders (P = 0.011 for IgG) (P = 0.006 for IgA). Receiver Operating Characteristic curve (ROC curve) analysis revealed that the area under ROC curves of IgA is higher compared to IgG (0.80 0Vs 0.890). In conclusion the current study revealed that patients with H. pylori infection have an increased tendency to develop urticaria. H. pylori reactive IgA antibodies correlate best with the infection.
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