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Biomedical subjects

E Mason

Publications and source records attributed to E Mason.

At least 37 records · Page 2Linked to original sources
PubMed1997

Measles complications: the importance of their management in reducing mortality attributed to measles.

OBJECTIVE: To determine the effect of rates of complications among cases and management of complicated cases on measles case fatality rates. DESIGN: Measles disease surveillance. SETTING: City of Gweru, Department of Health. SUBJECTS: Children aged zero to 15 years. MAIN OUTCOME MEASURES: Case fatality rates. RESULTS: Measles case fatality rates declined from 47.6 in 1967 to zero in 1989. Between 1967 and 1978 respiratory infections were the predominant complications (66.5%), while after 1979 diarrhoea was the predominant complications (60.6%). A significant partial correlation coefficient was observed between rates of mortality among complicated cases and case fatality rates (r = 0.89, df = 20, p < 0.001). CONCLUSION: Good management of complicated cases may have contributed towards the decline in measles case fatality rates.

Adolescent↗
PubMed1997

Comparison of protection afforded by single measles vaccination and late revaccination schedules.

An intervention study compared the protection afforded vaccinees by single measles vaccination and late revaccination schedules in 1990-94. During the intervention a single revaccination (after initial vaccination at nine months of age) was applied to children at any point in time between 12 and 23 months of age. Cases of measles aged 10-23 months were identified through an active surveillance system and in this period 5, 11 and 11 cases of revaccinated, single vaccination and unvaccinated children were identified. Measles incidence rates were 392.2-415.6 (mean = 405.6, SD = 6.7), 75.4-112.1 (median = 91.7, SD = 13.3) and 12.8-15.2 (mean = 13.9, DS = 0.99) per 100,000 population in children who were unvaccinated, with single vaccination and revaccinated respectively. Relative risk of contracting measles in children who were unvaccinated or with single vaccination was 26.5-32.5 (mean = 29.4, SD = 2.3) and 5.8-8.8 (mean = 6.8, SD = 1.2) respectively compared with revaccinated children. Vaccine efficacies that were determined were 73-81% (mean = 77.2, SD = 2.9) and 96.2-96.9% (mean = 96.6, SD = 0.27) for single vaccination and late revaccination schedules respectively. It was concluded that late revaccination affords vaccinees better protection than single vaccination through improvement in vaccine.

Age Factors↗
PubMed1996

Chronic lung disease following neonatal ventilation. I. incidence in two geographically defined populations.

The objective of this study was to compare the incidence of chronic lung disease following neonatal ventilation in two geographically defined populations. Prospective data collection was carried out over a 1 year period from March 11, 1990 to February 28, 1991 in the Trent Health Region (England) and in British Columbia, Canada. All infants < or = 32 weeks gestation and/or < or = 1500 g birthweight born to mothers normally resident in either the Trent Health Region or British Columbia were included. The main outcome measures were mortality rate, presence of chronic lung disease, days of ventilation, and oxygen used by each infant. The proportion of shortened gestation, low birthweight babies was 1.5% in Trent and 1.2% in British Columbia (957 of 63,350 births in Trent and 526 of 45,333 births in British Columbia). There were no significant differences in mean birthweight or gestation between the two cohorts, but there was a trend towards lower mortality for infants 750-1500 g birthweight in British Columbia. The incidence of chronic lung disease (using either of two definitions) was significantly higher in British Columbia, with a corresponding greater amount of respiratory care required. This occurred despite higher use of antenatal steroids and surfactant therapy in the British Columbia group. We conclude that there are important clinical and resource implications resulting from the number of ventilator and oxygen days used by the preterm population in terms of planning of neonatal services. The role of individual treatment modalities in producing differences in the incidence of chronic lung disease warrants further study in the setting of a geographically defined population.

Birth Weight↗
PubMed1996

Chronic lung disease following neonatal ventilation. II. Changing incidence in a geographically defined population.

The objective of this study was to examine the change in incidence of chronic lung disease following neonatal ventilation in a geographically defined population. Prospective data were collected over two 1-year periods (1987-1988 and 1990-1991) in the Trent Health Region, England. All infants were < or = 32 weeks gestation and/or < or = 1500g birthweight, born to mothers normally resident in the Trent Health Region. The principal outcome measures were mortality rate, presence of chronic lung disease, days of ventilation, and oxygen used by each infant. The proportion of low gestation, low birthweight babies was 1.5% in each period, made up of 897 and 925 babies from 61,050 and 63,350 births, respectively. There was a significant fall in mortality in infants of 750-1500g birthweight. However, the incidence of chronic lung disease (using either of two definitions) rose significantly between the two periods, with a corresponding large rise in the amount of respiratory care required. The contribution of various antenatal factors previously thought to be related to the development of chronic lung disease was examined. Birthweight and gestation were shown to be of overwhelming significance. We concluded that improvements in neonatal care, including the introduction of surfactant therapy, improved survival for some infants at the expense of an increased incidence of chronic lung disease. Clearly the hoped-for cost saving following the introduction of surfactant therapy has not occurred.

Bronchopulmonary Dysplasia↗
PubMed1996

A retrospective analysis of laparoscopically assisted ventriculoperitoneal shunts.

BACKGROUND: During the last two years, laparoscopy has been utilized to facilitate the rapid, safe and direct placement of the abdominal component of ventriculoperitoneal shunts. This study was undertaken to review the feasibility, benefits, technique, and clinical application of laparoscopically assisted ventriculoperitoneal (LAVP) shunt placement. METHODS: A retrospective analysis of the records of six patients who underwent LAVP shunt placement was undertaken. The sex, age, technique, indication for surgery, comorbid conditions, complications operative time, results, and mortality were noted. RESULTS: All patients underwent successful shunt placement. This included placement in the face of previous abdominal surgery, including a percutaneous gastrostomy. The one major complication, hemothorax, was not associated with the laparoscopic portion of the procedure. CONCLUSIONS: Using basic laparoscopic skills and nonspecialized equipment, laparoscopic assistance in ventriculoperitoneal shunt placement offers easy, direct placement of the intraabdominal portion of the catheter in most situations and provides definite patient benefits.

Adolescent↗
PubMed1995

Evolutionary conservation of a cell fate specification gene: the Hydra achaete-scute homolog has proneural activity in Drosophila.

Members of the Achaete-scute family of basic helix-loop-helix transcription factors are involved in cell fate specification in vertebrates and invertebrates. We have isolated and characterized a cnidarian achaete-scute homolog, CnASH, from Hydra vulgaris, a representative of an evolutionarily ancient branch of metazoans. There is a single achaete-scute gene in Hydra, and the bHLH domain of the predicted gene product shares a high degree of amino acid sequence similarity with those of vertebrate and Drosophila Achaete-scute proteins. In Hydra, CnASH is expressed in a subset of the interstitial cells as well as differentiation intermediates of the nematocyte pathways. In vitro translated CnASH protein can form heterodimers with the Drosophila bHLH protein Daughterless, and these dimers bind to consensus Achaete-scute DNA binding sites in a sequence-specific manner. Ectopic expression of CnASH in wild-type late third instar Drosophila larvae and early pupae leads to the formation of ectopic sensory organs, mimicking the effect of ectopic expression of the endogenous achaete-scute genes. Expression of CnASH in flies that are achaete and scute double mutants gives partial rescue of the mutant phenotype, comparable to the degree of rescue obtained by ectopic expression of the Drosophila genes. These results indicate that the achaete-scute type of bHLH genes for cell fate specification, as well as their mode of action, arose early and have been conserved during metazoan evolution.

Amino Acid Sequence↗
PubMed1995

Questioning the level of efficacy of the measles vaccine in use in Zimbabwe.

A prospective study was carried out between 1987 and 1989 in the City of Gweru (Zimbabwe) to assess the efficacy of the measles vaccine. The vaccine efficacy assessment was carried out on an epidemiological basis by relating measles transmission in the vaccinated and unvaccinated children aged 10 to 23 months. Measles cases were identified on the basis of a standard case definition and data on occurrence of measles cases was collected through an active surveillance system. Efficacies of 73 pc, 82 pc and 77 pc were calculated for the years 1987, 1988 and 1989 respectively. Over the three year period mean efficacy was found to be 77 pc (95 pc confidence interval 75 to 79 pc). The vaccine efficacies found in this study were lower than 85 pc which is the officially accepted efficacy of the measles vaccine that is in use in Zimbabwe. The low vaccine efficacy found in this study is attributed to the fact that the measles vaccine is applied (at nine months of age) when probably 10 to 20 pc of children still have prenatally acquired maternal antibodies. It is suggested that further studies be carried out in Zimbabwe to enable the country to define the way forward.

Age Distribution↗
PubMed1995

Antimicrobial susceptibilities of Shigella dysenteriae type 1 isolated in Zimbabwe--implications for the management of dysentery.

Shigella dysenteriae type 1 was cultured from 56/170 (33 pc) rectal swab specimens collected from patients presenting to hospitals in Harare, Zimbabwe with dysentery. All of the isolates were resistant in vitro to trimethoprim-sulfamethoxazole, with MICs > 32 mg/l, and all except one were resistant to ampicillin, most with an MIC > 256 mg/l. One isolate was resistant to nalidixic acid (MIC > 256 mg/l), but all of the others were sensitive, most with an MIC of 2 mg/l or less. Using antibiotic disks, 96 pc isolates were resistant to chloromphenicol and 94 pc to tetracycline. All isolates were sensitive in vitro to gentamicin. On the basis of these findings, we suggest that commonly available antibiotics including ampicillin, cotrimoxazole, chloramphenicol or tetracycline should not be used for the treatment of dysentery. The most appropriate antimicrobial agent at the present time would be nalidixic acid. Resistance to this is, however, likely to emerge and data on susceptibilities to fluoroquinolones as well as to cephalosporins should be obtained so that further recommendations can be given timeously.

Child↗
PubMed1994

Attitudes, knowledge, and skills of internal medicine residents regarding pre-conception care.

BACKGROUND: A questionnaire was designed based on current recommendations for pre-conception care and care of women at the time of diagnosis of pregnancy to evaluate internal medicine residents' attitudes, knowledge, and clinical management skills in the pre-conception care of healthy women and women who have chronic diseases during their reproductive years. METHOD: In early 1991, a self-administered questionnaire was distributed to 104 internal medicine residents at Cook County Hospital, a large, inner-city public hospital. Statistical analysis included the use of chi-square comparison, Pearson correlation, and Student's t-test. RESULTS: Seventy-nine of the residents completed questionnaires. Their levels of knowledge and management skills regarding pre-conception care were relatively low compared with standard recommendations. The residents' attitudes, however, were favorable toward the importance of the topic. Residency training did not appear to improve the residents' management skills, as there was no significant difference in skills among the first-, second-, and third-year residents. CONCLUSION: That the residents' levels of knowledge and management skills were low (despite their favorable attitudes) suggests that the current curriculum for primary care training in internal medicine needs to be revised to improve the readiness of residents to take care of women of reproductive age.

Attitude of Health Personnel↗
PubMed1994

An institutional review of the management of choledocholithiasis in 1616 patients undergoing laparoscopic cholecystectomy.

At Georgia Baptist Medical Center, 1616 patients underwent laparoscopic cholecystectomy between December 1989 and December 1992; and 103 perioperative endoscopic retrograde cholangiopancreatography (ERCP) procedures were performed, 79 preoperative and 24 postoperative. Endoscopic sphincterotomy with stone extraction was performed in 49 patients (4.7%). Normal ERCP was noted in 46 patients (44%), four patients failed stone extraction preoperatively, and two patients failed extraction postoperatively (5.7%). Four patients had small stones (< 2 mm) managed expectantly without sphincterotomy. Ten laparoscopic common bile duct explorations and eight open common bile duct explorations were performed without retained stones after these procedures. The incidence of detected choledocholithiasis requiring intervention was 4.4 per cent, which is significantly lower than the published incidence of 8 to 15 per cent. It is assumed that a higher percentage of stones may have been detected with liberal or routine use of cholangiography. The clinical significance of these potentially missed stones have not been manifest in our series to date. The authors believe that although improved patient selection may lower the percentage of normal ERCP, this combination of minimally invasive techniques provides a satisfactory approach to choledocholithiasis.

Cholangiography↗
PubMed1993

A lamb model for human respiratory syncytial virus infection.

Respiratory syncytial virus (RSV) is the most important cause of bronchiolitis and pneumonia in young children. The development of an animal model of RSV disease serves to better understanding the pathophysiology of airway disease from RSV infection in infants and children. Groups of six lambs were inoculated intratracheally (IT) or intranasally (IN) with a human strain of RSV (H-RSV). For controls 8 lambs received IT virus-free cell lysate. Tachypnea and fever were observed significantly more often following IT than following IN inoculation of H-RSV or IT placebo (for tachypnea: 20 of 69 days, 5 of 63 days, and 3 of 89 days, respectively, P < 0.001; for fever: 6 of 69 days, 0 of 63 days, and 1 of 89 days, respectively, P < 0.02). Nasal fluid production was significantly more frequent in both IT (14 of 69 days) and IN (15 of 63 days) groups than in the placebo group (2 of 87 days, P < 0.001). Postvaccination geometric mean titers (GMT, arithmetic transformation of log 2) of RSV-specific neutralizing antibody were significantly increased in the IT H-RSV group compared with postplacebo GMTs at 1 week (72 vs. 6.7, P < 0.03). By the second week postinoculation both H-RSV-infected groups had comparable levels of RSV-specific neutralizing antibody titers and had significantly greater GMTs for the second through to the fourth week than the placebo group (144, 128, and 4.8, respectively P < 0.0008). Bacterial isolates of the upper airway were comparable among the three groups. Histopathology at day 28 postinoculation was unremarkable for the three study groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Is laparoscopic herniorrhaphy an effective alternative to open hernia repair?

While the inguinal approach to hernia repair remains the standard of care, laparoscopic hernia repair techniques are rapidly evolving. The first 102 laparoscopic hernia repairs were reviewed. Reported herein are the types of hernias repaired, length of hospital stay, early recurrence rate, complications, and assessment of postoperative pain. The long-term recurrence rate has yet to be determined. From these results, it is felt that in select patients, laparoscopic hernia repair is an effective surgical alternative in the treatment of inguinal hernia.

Activities of Daily Living↗
PubMed1993

Kainate-induced changes in opioid peptide genes and AP-1 protein expression in the rat hippocampus.

In the rat hippocampus, jun, c-fos, and fos-related antigen immunoreactivity, AP-1 DNA binding, and opioid peptide gene expression were examined after kainate treatment to determine whether the induction and DNA binding of AP-1 transcription factors are correlated with the expression of the opioid peptide genes. One and one-half hours after kainate administration, fos-related antigen and jun immunoreactivity and AP-1 DNA binding were induced; maximal elevation was observed after 4.5 h. Transcription factor expression and DNA binding increased in a dose-dependent manner. Preprodynorphin and preproenkephalin mRNA induction was also dose dependent. The anticonvulsants, pentobarbital and diazepam, effectively blocked electroencephalographic seizure activity caused by kainate treatment, whereas valproic acid was approximately 50% effective. Opioid peptide gene expression, fos-related antigen and jun immunoreactivity, and AP-1 DNA binding all reflected similar reductions after anticonvulsant treatment. Therefore, expression and DNA binding activity of the AP-1 transcription factors are correlated with opioid peptide gene expression in the rat hippocampus.

Animals↗
PubMed1993

Meralgia paresthetica: a complication of laparoscopic herniorrhaphy.

Laparoscopic herniorrhaphy is a new and presently evolving technique applied to the repair of inguinal defects. Many different authors have described various methods by which this can be achieved. Some of these include the transabdominal preperitoneal approach, the plug technique, the intraperitoneal onlay of mesh, and the extraperitoneal approach. The authors have performed 252 laparoscopic hernia repairs utilizing a form of the transabdominal preperitoneal procedure that is referred to as the "transperitoneal anatomic approach." The development of new procedures or the modification of existing procedures can create new problems or alter the pattern of traditional complications. These problems must be thoroughly evaluated and reported if repetition of these errors is to be avoided. Five cases of meralgia paresthetica are reported that resulted from staple entrapment of the lateral femoral cutaneous nerve during laparoscopic herniorrhaphy. An understanding of the preperitoneal inguinal anatomy and precise placement of staples will allow avoidance of this complication.

Adult↗