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Biomedical subjects

J B Wilson

Publications and source records attributed to J B Wilson.

At least 19 recordsLinked to original sources
PubMed1995

Innovative community-based postgraduate training for obstetrics and gynecology in west Africa.

OBJECTIVE: To describe a unique international effort to develop a training program in West Africa that would be of similar quality to any other in the world (but with sensitivity to cross-cultural needs) and would retain physicians in West Africa to improve women's health in that part of the world. METHODS: Step-by-step formulation of a program included initial trainee recruitment, the inclusion of foreign guest faculty, and the establishment of institutional libraries. This was followed by a phase of curriculum development, recruitment of West African faculty, and organization of an innovative, community-based fourth year. RESULTS: Between ten and 12 postgraduates will have completed the program by January 1996, and will be placed in Ghana. More than 60% of Ghanaian postgraduates have passed the relevant regional examinations, compared with less than 25% of candidates from other countries. Nine Ghanaian specialists have returned to Ghana to become faculty members in the program. Over 20 published peer-reviewed articles have resulted from this program since 1989. The number of residents being trained has increased from three to 28. Seven new residents joined the program in 1994. An early reduction in maternal mortality from 9.9 deaths per 1000 births in 1991 to 4.2 deaths per 1000 births in 1992 was noted when senior postgraduates took over labor and delivery at the teaching hospital in Accra, Ghana, where approximately 10,000 deliveries occur per year. CONCLUSION: Specialty training in obstetrics and gynecology that is specifically aimed at meeting the needs of West Africa has been initiated successfully. Long-range success will require support from regional governments and continued long-term commitments from the international community of obstetricians and gynecologists.

Africa↗
PubMed1995

Management of difficult intra operative bleeding by abdominal packing: report of four cases.

Difficult perioperative bleeding in four obstetric and gynaecology patients was managed with temporising abdominal packs left in place with abdominal closure for 48-72 hours in order to avoid deaths on the operating table when blood loss could not be adequately replaced and hemostasis could not be secured. Abdominal re-opening to remove the packs was undertaken. Three of the patients were eventually discharged home after satisfactory recovery. The fourth died of sepsis three weeks after the fourth re-operation and bilateral internal iliac artery ligation. Abdominal packing thus has a place in the management and salvage of patients with difficult obstetric and gynaecologic perioperative bleeding.

Adolescent↗
PubMed1994

A novel deletion of approximately 27 kb including the beta-globin gene and the locus control region 3'HS-1 regulatory sequence: beta zero-thalassemia or hereditary persistence of fetal hemoglobin?

A novel deletion of approximately 27 kb with the 5' breakpoint 1.5 to 2.2 kb upstream of the beta-globin gene, and the 3' breakpoint approximately 24 kb downstream of the beta-globin gene, has been found in five members of two families from Southeast Asia (Vietnam and Cambodia). Six members of another family from China, previously reported from our laboratory, have also been shown to carry this deletion. The patients presented with mild hypochromia and microcytosis, a hemoglobin (Hb) A2 level of approximately 4.0%, and a markedly increased, heterocellularly distributed, Hb F level (14.0 to 26.0%). In vitro globin-chain synthesis showed a mild imbalance with appreciable gamma-chain compensation (alpha/beta + gamma ratio of 1.46). The 3' end of this deletion includes the 3'HS-1, and we hypothesize that removal of this region results in the loss of its gamma-globin gene-silencing effect, which causes a markedly elevated Hb F level with a modest increase in Hb A2 levels, unlike the situation in other deletional beta zero-thalassemias. The possible influence of particular sequence variations in the locus control region 5'HS-2 and the G gamma promoter, present on the chromosome with this deletion, on the overall gamma-globin gene should also be considered.

Adolescent↗
PubMed1994

Quantities of alpha Q chain variants in heterozygotes with and without a concomitant beta-thalassemia trait.

We have analyzed the quantities of alpha x chain-containing hemoglobins (alpha 2 x beta 2 and alpha 2 x delta 2) in 14 heterozygotes for Hb Q-India [alpha 64(E13)Asp-->His] or Hb Q-Thailand [alpha 74(EF3)Asp-->His]; both amino acid replacements are the result of mutations in the alpha 1-globin gene. Five of these persons (three with Hb Q-India and two with Hb Q-Thailand) had an additional beta(0)-thalassemia heterozygosity. The average quantities for Hb Q + Hb Q2 in the four groups were 17.2% (alpha alpha Q/alpha alpha; beta A/beta A), 9.5% (alpha alpha Q/alpha alpha; beta A/beta(0) Th), 26.8% (-alpha Q/alpha alpha; beta A/beta A), and 16.95% (-alpha Q/alpha alpha; beta A/beta(0) Th). These variations can best be explained by a posttranslational control mechanism; an imbalance in the alpha A, alpha Q, and beta A chain ratio will favor the alpha 2 Q beta 2 formation when an alpha-thalassemia is present and will reduce its formation in the presence of a beta-thalassemia heterozygosity.

Adolescent↗
PubMed1994

Eclampsia: 134 consecutive cases.

OBJECTIVE: A retrospective analysis of all cases of eclampsia (134) at Korle Bu Teaching Hospital, Accra, Ghana, in 1991, was undertaken to determine future directions in prevention and management. METHODS: One hundred and thirty-four consecutive cases of eclampsia were reviewed to assess possible risk factors, associated medical impact, and the usefulness of prenatal care. RESULTS: Risk factors for the development of eclampsia include: young age, delivery in the rainy season, nulliparity, multiple pregnancy, prolonged labor, and lack of prenatal care. Eclampsia is associated with high maternal and perinatal mortality. CONCLUSIONS: Future emphasis on prenatal clinics, and earlier detection and management of pre-eclampsia should lessen the incidence of this severe obstetric emergency.

Adolescent↗
PubMed1994

Diagnosing unruptured ectopic pregnancy.

OBJECTIVE: A retrospective analysis of the management of ectopic pregnancy at Korle Bu Teaching Hospital in Accra, Ghana, to assess the impact of the introduction of ultrasonography as a diagnostic tool. METHODS: All charts of patients with ectopic pregnancies from 1 January 1986 to 31 December 1990 were analyzed. The management of those patients who had transabdominal ultrasonography was compared with those who had not. RESULTS: The use of ultrasonography increased the number of unruptured ectopic pregnancies from 0.3% to 8.5% (P < 0.001). This also reflected a reduction in misdiagnoses, blood transfusions, and maternal deaths. CONCLUSIONS: The reasonable use of modern technology can be of great assistance even in developing countries, as shown by the positive impact of the use of ultrasonography to aid in the diagnosis of ectopic pregnancy in Ghana, West Africa.

Developing Countries↗
PubMed1994

Generating colour and texture verniers.

This paper describes computer graphics techniques for presenting visual stimuli in a vernier format composed out of coloured texture patterns. Such stimuli can be used to investigate the performance at the task of localising boundaries mediated by changes in colour and/or texture. We summarise the contents as follows: (1) Techniques for presenting visual stimuli are reviewed with a view to how they might be used to present colour and texture verniers. (2) The design of the vernier stimuli for the localisation task is considered. (3) Significant elements of this design are: (a) the use of non-isoplanatic textures to avoid interference effects at boundaries, (b) the modulation of the texture patterns along axes in MacLeod-Boynton colour space so that relative retinal cone contributions are controlled, and (c) the use of double-buffering, colour map manipulation, and contrast randomisation techniques to avoid problems commonly encountered when presenting computer graphics stimuli on colour monitors. (4) Results of a psychophysical experiment that presents colour and texture verniers are reported elsewhere.

Color Perception Tests↗
PubMed1994

Hb Fannin-Lubbock in five Spanish families is characterized by two mutations: beta 111 GTC-->CTC (Val-->Leu) and beta 119 GGC-->GAC (Gly-->Asp).

We have sequenced the amplified beta-globin genes of five, apparently unrelated, Spanish adults with a fast-moving hemoglobin variant, and observed a GGC-->GAC mutation at codon 119 which identified the abnormality as Hb Fannin-Lubbock or alpha 2 beta (2)119(GH2)Gly-->Asp. In addition, we found a GTC-->CTC change at codon 111 which leads to a Val-->Leu replacement at this location. Protein analysis of the beta A and beta X chains from one of these individuals confirmed that both mutations are located on the same chromosome. It is hypothesized that some other known variants may carry an additional mutation in one of their exons, resulting in a silent amino acid substitution which may have an effect on some physicochemical property. In the case of Hb Fannin-Lubbock, it appears likely that the Val-->Leu replacement at beta 111, rather than the Gly-->Asp replacement of beta 119, is the cause of the instability of the variant. The Hb Fannin-Lubbock variant in these Spanish families had a normal oxygen affinity.

Adult↗
PubMed1993

The M gamma chain of human fetal hemoglobin is an A gamma chain with an in vitro modification of gamma 141 leucine to hydroxyleucine.

We have reanalyzed the structure of the gamma T-15 peptide from the minor M gamma chain of human hemoglobin (Hb) F. Amino acid analysis confirmed that the Leu 141 residue was missing from position 9 of this peptide, and liquid secondary ion mass spectrometry indicated that it was replaced, not by methionine (residue mass 131) as previously believed, but by an amino acid of mass 129. By analogy with the recently reported oxidation of the corresponding leucine at position gamma 141 of the unstable Hb Atlanta, it appears that the M gamma chain also results from the oxidation of gamma 141 to hydroxyleucine (residue mass 129). The finding that the proportion of the M gamma chain increased when red cell lysates were prepared with carbon tetrachloride prompted us to reinvestigate the oxidation mechanism involved in the formation of beta 141 hydroxyleucine in Hb Atlanta. Oxidation of the beta 141 residue could be detected when carbon tetrachloride was used in the lysis protocol, while conversion of oxyhemoglobin to carbon monoxyhemoglobin prior to carbon tetrachloride treatment prevented oxidation. It therefore appears that the hydroxylation of Leu 141 is not an in vivo process in the circulating red cell. Perhaps leucine at position 141 of the beta, gamma, and delta chains (and at position 136 of the alpha chain), which forms a contact with heme and is located directly across the heme plate from the E helix, is oxidized to hydroxyleucine at a very low rate forming minute amounts of modified chains; this process is accelerated by treatment with agents such as carbon tetrachloride and prolonged exposure to air.

Adult↗
PubMed1993

Maternal height as a predictor of vaginal delivery.

OBJECTIVE: The purpose of the study was to establish a relationship between maternal height and vaginal delivery. METHOD: A prospective study of 900 primigravidas in labor in the Department of Obstetrics and Gynecology, Korle-Bu Teaching Hospital was conducted. A questionnaire was developed and administered by research assistants. The results were analyzed using the X2-test. RESULTS: Of the 900 patients who delivered, 538 were studied. The remaining patients were excluded from the study because of factors described under exclusion criteria. A critical height of 154 cm was chosen as the screening height for 'at risk' of cephalopelvic disproportion (CPD). This height would identify 71.1% of women who would develop CPD. CONCLUSION: Short women with heights up to 150 cm are at risk of failing spontaneous vaginal delivery and should be referred to hospitals where labor could be closely monitored and cesarean section performed if necessary.

Body Height↗
PubMed1993

Menopausal age of Ghanaian women.

OBJECTIVE: The purpose of the study was to determine the age of menopause among Ghanaian women. METHOD: A prospective survey involving 152 women in Akosombo District in Ghana was conducted. A questionnaire was developed including: age at menopause, symptoms of hot flushes or flashes, palpitations, anxiety, sleeplessness, headaches, frequency of urine, depression, irritability, tiredness, weight gain, poor memory and attitudes to coitus. RESULT: Of 152 women interviewed, 29 were excluded because they were not sure of their birth dates and 123 women were analyzed. The mean and median ages at menopause were 48.05 years +/- 3.62 S.D. and 48 years respectively. The major symptoms at menopause were tiredness 79.9%, sleeplessness 71.0%, palpitations 63.7%, weight gain 61.8%, hot flushes 56.5%, and irritability 56.5%. However, 85.6% of the women who experienced hot flushes reported this to be the most unpleasant. CONCLUSION: 1. The age at menopause in Ghanaian population was 48.05 +/- 3.62. 2. Tiredness, sleeplessness, palpitations, weight gain, hot flushes, irritability, anxiety and headache were the major symptoms at menopause. 3. Hot flushes or flashes was the most disturbing symptom at menopause.

Age Factors↗
PubMed1993

Schistosomiasis and cervical cancer in Ghana.

OBJECTIVE: To discover a possible association between schistosomiasis and cervical dysplasia and/or cervical cancer in Ghana, West Africa. METHOD: Two groups of 24 subjects each were identified, one group from a schistosomiasis-endemic area and a control group from a non-endemic area. Random cervical biopsies, cervical cytology and human papilloma virus (HPV) DNA testing were performed on all subjects. Demographic data were analyzed using Student's t-test. Histologic and DNA findings were analyzed using Fisher's exact test. RESULTS: From the endemic area, 46% of subjects had histologic evidence of schistosomiasis infection of the cervix. No evidence of dysplasia or cancer on cervical cytology was noted in this group. Mild dysplasia was noted in random cervix biopsies in one patient, and 8 patients had evidence of HPV infection of the cervix. No patient from the non-endemic area had cytologic or histologic evidence of cervical dysplasia or cancer. Eleven subjects in this group had evidence of HPV infection. CONCLUSION: This study does not reveal an association between cervical schistosomiasis and cervical dysplasia or cervical cancer on cytology or histology. Both study groups demonstrated a high degree of infection with HPV, however. It may be the HPV and not the schistosomiasis which is responsible for the development of uterine cervix cancer.

Adult↗