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BACKGROUND: In recent years, research data warehouses moved increasingly into the focus of interest of medical research. Nevertheless, there are only a few center-independent infrastructure solutions available. They aim to provide a consolidated view on medical data from various sources such as clinical trials, electronic health records, epidemiological registries or longitudinal cohorts. The i2b2 framework is a well-established solution for such repositories, but it lacks support for importing and integrating clinical data and metadata. OBJECTIVES: The goal of this project was to develop a platform for easy integration and administration of data from heterogeneous sources, to provide capabilities for linking them to medical terminologies and to allow for transforming and mapping of data streams for user-specific views. METHODS: A suite of three tools has been developed: the i2b2 Wizard for simplifying administration of i2b2, the IDRT Import and Mapping Tool for loading clinical data from various formats like CSV, SQL, CDISC ODM or biobanks and the IDRT i2b2 Web Client Plugin for advanced export options. The Import and Mapping Tool also includes an ontology editor for rearranging and mapping patient data and structures as well as annotating clinical data with medical terminologies, primarily those used in Germany (ICD-10-GM, OPS, ICD-O, etc.). RESULTS: With the three tools functional, new i2b2-based research projects can be created, populated and customized to researcher's needs in a few hours. Amalgamating data and metadata from different databases can be managed easily. With regards to data privacy a pseudonymization service can be plugged in. Using common ontologies and reference terminologies rather than project-specific ones leads to a consistent understanding of the data semantics. CONCLUSIONS: i2b2's promise is to enable clinical researchers to devise and test new hypothesis even without a deep knowledge in statistical programing. The approach presented here has been tested in a number of scenarios with millions of observations and tens of thousands of patients. Initially mostly observant, trained researchers were able to construct new analyses on their own. Early feedback indicates that timely and extensive access to their "own" data is appreciated most, but it is also lowering the barrier for other tasks, for instance checking data quality and completeness (missing data, wrong coding).

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AIM: This study assessed the prevalence and determinants of electrocardiographic abnormalities in a group of type 2 diabetes patients recruited from two referral centres in Cameroon. METHODS: A total of 420 patients (49% men) receiving chronic diabetes care at the Douala General and Yaoundé Central hospitals were included. Electrocardiographic abnormalities were investigated, identified and related to potential determinants, with logistic regressions. RESULTS: The mean age and median duration of diagnosis were 56.7 years and four years, respectively. The main electrocardiographic aberrations (prevalence %) were: T-wave abnormalities (20.9%), Cornell product left ventricular hypertrophy (16.4%), arrhythmia (16.2%), ischaemic heart disease (13.6%), conduction defects (11.9%), QTc prolongation (10.2%) and ectopic beats (4.8%). Blood pressure variables were consistently associated with all electrocardiographic abnormalities. Diabetes-specific factors were associated with some abnormalities only. CONCLUSIONS: Electrocardiographic aberrations in this population were dominated by repolarisation, conduction defects and left ventricular hypertrophy, and were more related to blood pressure than diabetes-specific factors.

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In order to identify a rapid feasible and adaptable method of haemoglobin measurement for use in a blood bank, two methods were evaluated against the automated method in 204 blood donors in Yaoundé, Cameroon. Anaemia was defined as Haemoglobin<12 g/dl. Using the World Health Organisation (WHO) haemoglobin colour scale (HCS), the Hemocue method (HemoCue AB, Angelhom, Suède) and the Celly Electronic counter (Hycel Diagnostics, Reims, France), anaemia was found in 27.5, 29.4 and 31.9% of donors respectively (P<0.05). The sensitivity and specificity of the HCS was 75.38 and 94.96% respectively compared to 86.15 and 97.13% respectively in the HemoCue method. Correlation studies between each method compared to automated method showed r=0.70 for the WHO. colour scale method and 0.91 for the Hemocue method. Using the Bland and Altman statistical method, the haemoglobin distribution around the mean was wider in the WHO scale (-2.74;+2.96) than in the Hemocue method (-2.06; +1.38). We conclude that while the two methods can be used to detect anaemia in the blood bank, that the Hemocue method is more sensitive and more specific.

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There is evidence from clinical case reports and epidemiological studies that human immunodeficiency virus (HIV) can be transmitted through oral sex. Herpes viruses that appear in the oral mucosa might influence the oral replication of HIV. A review of data suggesting that interactions occur between HIV and herpes viruses indicates that such interactions might operate in the oral mucosa. Defining the mechanisms by which herpes viruses interact with HIV in the oral mucosa should permit intervention measures to be targeted more precisely.

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A 24-year-old patient with homozygous sickle cell disease developed a stress fracture of the femur. Successive x-rays demonstrated defective ossification and a spontaneous unicortical fracture with no notion of trauma or stressful activities (e.g. sports) followed six months later by a bicortical fracture with displacement and periosteal reaction leading to the diagnosis of stress fracture. This type of fracture has not been reported previously in sickle cell disease. The patient was treated with centromedullary nailing. The follow-up was uneventful. Bone healing was achieved at three months. The patient was pain free and could walk without crutches. Stress fracture is a potential diagnosis in homozygous sickle cell disease patients with defective ossification who present spontaneous pain even when plain x-rays do not visualize an overt fracture. Computed tomography or magnetic resonance imaging should be performed when available. Conventional treatment with nailing provides successful cure with good functional outcome.

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We developed and evaluated two peptide-based immunoassays to confirm and discriminate between group M and group O HIV-1 infection. These assays are based on in vitro competition for antibody binding between M and O peptides. The first EIA is based on competition between group M and group O gp41 immunodominant domains and the second on competition between group O and group M V3 regions of gp120. Two panels of sera were used: the first consisted of 109 sera collected from 27 group O- and 92 group M-infected patients in whom the HIV isolates had been genotyped by sequencing or heteroduplex mobility assay. In this panel, the combination of the two assays correctly discriminated 106 samples (100% group O and 96.7% group M samples). The second panel, used for the field evaluation of the two assays, consisted of 157 samples from HIV-1-infected Cameroonian patients, 33 strains having been genotyped. The combination of the two techniques in a serogrouping algorithm discriminated 147 of these samples, 74 being HIV-1 group O and 73 group M. These results always correlated with genotyping results. The 10 sera that were not successfully classified by these assays were from early seroconverters. Altogether, the two assays clearly differentiated 263 of 276 (94.9%) samples in the two panels. On the basis of the genotyping results, the positive predictive value for group discrimination in the two panels was 100% for both GSEIA assays. Our peptide-blocking group-specific EIAs for differentiation and confirmation of HIV-1 group M and group O infection are complementary tools for epidemiological studies and surveillance of HIV-1 group O strain trafficking.

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OBJECTIVES: To study the presence of HIV-1 group O infection among HIV-infected people in Cameroon and to further characterize the HIV-1 group O infections. DESIGN AND METHODS: During a 2-year survey (1994-1995), all samples tested positive in screening methods in the National Reference and Public Health Laboratory, Centre Pasteur, Yaoundé, Cameroon were identified as HIV-1 group M, HIV-1 group O or HIV-2 by using a serological algorithm. HIV-1 group M and HIV-1 group O were distinguished on the basis of competitive enzyme-linked immunosorbent assay (ELISA) reactivity against gp41 group M recombinant protein. HIV-1 group O infections were confirmed by using group O-specific V3 synthetic peptides. HIV-1 group O strains were isolated by lymphocyte cocultures, proviral DNA was amplified with specific primers, and sequencing was performed on the C2V3 and gag regions. RESULTS: Of the 8,331 screened samples, 3,193 were HIV-reactive, 2,376 (74%) of which were considered to belong to group M. The 817 (26%) that had reacted poorly or not at all against group M gp41 were further characterized: 10 were confirmed as HIV-2 and 82 as HIV-1 group O, the others being indeterminate (n = 285) or negative (n = 440). The frequency of group O relative to group M ranged from 1% in Far North province to 6.3% in the capital. There was no difference in sex, age or frequency of clinical manifestations between group M and group O infections. Group O infection was confirmed in a subset of cases by polymerase chain reaction (n = 14), with perfect concordance. Sequencing and phylogenetic analyses confirmed the high variability inside group O. CONCLUSIONS: Group O and group M epidemiological patterns are known to be similar so the reason for the lower prevalence of group O remains to be found. The wide distribution of group O infection in all Cameroonian provinces underlines the importance of further characterizing the epidemic spread and diffusion of this group.

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Increased sweat concentrations (92, 76 and 80 mEq/l) were observed in a 7-year-old boy with pitressin-resistant diabetes insipidus. All previous observations of elevated sweat electrolytes in diabetes insipidus have been in infants less than 10 months of age. The sweat test is an exceptionally reliable, sensitive and specific test for the diagnosis of Cystic Fibrosis. Pitressin-resistant diabetes insipidus is one of the diseases associated with elevated sweat test results.

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Les caracteristiques epidemiologiques et cliniques de 43 malades ages de 15 a 81 ans (moyenne = 45) admis consecutivement de mars a juin 1992 pour pneumopathie communautaire dans un hopital de 200 lits a Douala sont rapportees par les auteurs. La pneumopathie communautaire de l'adulte represente 4;6 pour cent des admissions dans cet hopital avec un sex-ratio de 2;3 et un taux eleve de population urbaine (70 pour cent). Les facteurs de risque les plus frequents etaient l'alcoolisme (67;4 pour cent); le tabagisme (44;5 pour cent) et l'infection a VIH (20;9 pour cent). [abstract terminated]

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It is possible to record movement parameters video densitometrically and synchronously by means of a video signal analysator at various points of the organ surface visible via fluoroscopic images (provided by videorecorder). Movement parameters of the heart surface were signed just in the same cardiac action by synchronous electrocardiography. There are some difficulties in this method according to evaluation with reference to laevocardiography in consequence of functional variety of the heart and the different exercise conditions. Small aneurysms of the cardiac apex were only seen when they were separated and located at the cardiac margin. Extended cardiac aneurysms were video densitometrically recorded as a paradoxical movement at the cardiac surface. A paradoxical movement was never seen with negative findings in laevocardiography.

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In invasive diagnostics of coronary heart disease (CHD), three each DSA examinations of the left coronary artery were performed at 2-minute intervals in ten patients subsequent to conventional examination by means of a left-side cardiac catheter and coronary angiography. While placing the patient in left anterior oblique (60 degrees) position, 6 ml each of ionic contrast medium were injected mechanically with a flow of 4 ml/sec at a pacemaker-induced heart rate of 100/min. Examinations were performed according to a standard mode and were evaluated via the image analysing computer APU of the Philips DVI-DSA system. The purpose of this approach was to analyse the examination conditions and a new improved evaluation algorithm in respect of stability, feasibility and sensitivity. 17 series were evaluated by two examiners who were independent of each other. The interobserver differences obtained were between 5% at the time of maximum density (Tmax) and 25% with exponential downward slope of the curve (lambda), with reference to the median value in each case. Scatter of the individual examinations around the median value of all the three DSA runs is 11 to 17% with the exception of lambda. A significant rise can be proven in the RCX region for the curve slope rise parameters "slope" and "RFL2". We interpret this as a genuine 1.2 to 1.3 fold regional flow increase due to the residual effect of the contrast medium. At the same time, this can be interpreted as an indicator for the good sensitivity of the method.(ABSTRACT TRUNCATED AT 250 WORDS)

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The sickle cell mutation (beta s) arose as at least three independent events in Africa and once in Asia, being termed the Senegal, Benin, Bantu and Indian types respectively. An investigation in Cameroon was carried out to determine whether the atypical sickle genes observed in the neighboring countries are the result of recombination or the presence of a sickle cell mutation of a different genetic origin. It was conducted on 40 homozygous SS patients followed at the Blood Transfusion Center in the capital city of Yaoundé. On 80 beta s chromosomes, 13 exhibited a novel polymorphic pattern that was observed three times in the homozygous state. This chromosome contains an A gamma T gene. The restriction fragment length polymorphism haplotype is different from all the other beta s chromosomes in both the 5' and 3' regions, but has previously been reported in sporadic cases. The (AT)8(T)5 sequence in the -500 region of the beta gene is specific and different from that of the Senegal, Benin, Bantu or Indian beta s genes. All the carriers of this specific chromosome belong to the Eton ethnic group and originate from the Sanaga river valley. This observation strongly argues for yet another independent origin of the sickle cell mutation in Africa, here referred to as the "Cameroon type". The Benin haplotype and a Benin/Bantu recombinant haplotype have been observed in the other studied populations: Ewondo, Bamiléké, Bassa, Yambassa and Boulou.

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In 10 cases of dilated cardiomyopathy the HLA-loci (A, B, C, DR) and marker expression on lymphocytes were studied. In this group the T4/T8-ratio was decreased and interleukin-2-expression was increased in relation to normals or patients with chronic coronary heart disease, respectively. 9 patients had the HLA-A1 or HLA-A2-locus in their siblings. In correlation analysis between immunological and hemodynamic parameters a good correlation of the number of NK-cells to the ejection fraction (r = 0.79) and negative correlation of helpercells (CD4) to the cardiac output were found (r = -0.80). The results of this attempt suggest an immunological pathogenesis of the dilated cardiomyopathy.

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Dans le cadre du Programme National de Lutte contre le SIDA au Cameroun; l'utilisation des filles libres educatrices a ete une des strategies adoptees ciblant les groupes a haut risque. Des resultats preliminaires ont ete presentes ailleurs et ont montre son positif impact. Afin d'evaluer cette strategie; une enquete de connaissances; attitudes; croyances et pratiques (ACP) aupres des filles qui pratiquaient la prostitution a Yaounde a ete faite. Cette enquete a eu pour but non seulement de faire le point sur les differentes actions educatrices menees aupres de ce groupe mais aussi de mettre sur pied des methodes d'education plus efficaces

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Eleven selected prostitute leaders were recruited who subsequently recruited 157 of their peers, bringing the total to 168. Sera was collected and tested for antibodies to HIV-1 and HIV-2 using a commercial enzyme-linked immunoabsorbent assay (ELISA); positive cases were confirmed by Western Blot (Dupont). A direct immunofluorescent method was performed on smears from the endocervical junction. Twelve of 168 (7.1%) of the women tested were found to be HIV-1 positive; none were found positive for HIV-2. Sixty six of 168 (38.3%) were found to be Chlamydia trachomatis (CT) positive; three cases (1.8%) were found to be positive for both HIV-1 and CT. Prostitutes are a high risk group in Yaoundé for HIV and chlamydia infections. The results in this study may not reflect the seriousness of the situation given the selected population used. Similar studies still need to be carried out. Prostitutes need to be educated about AIDS, other STDs and the use of condoms to protect their clients and themselves.

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The prevalence of the sickle cell trait in a school for elite young athletes in Cameroon, West Africa, was examined in order to evaluate whether the choice of an athletic career was influenced by its presence. The presence of hemoglobin AS was found in 27 of the 145 students attending the school (18.6%). Since the frequency of the sickle cell trait in the general Cameroonian population is 17.3%, we conclude that its presence is not a determinant factor involved in the choice of a professional sportive activity.

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Fifty-two cases of cholelithiasis were retrospectively studied in the Central Hospital of Yaounde over a period of 30 months. Nineteen males and 33 females with an average age of 40 years (range from 15 to 70 years). Forty-six p.c. of these patients had asymptomatic cholelithiasis and most of it consisted in only one gallstone. Etiologic factors found were: sickle-cell anemia, obesity, pregnancy and cirrhosis.

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