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E Thomas

Publications and source records attributed to E Thomas.

At least 163 records · Page 9Linked to original sources
PubMed1997

Regional distribution of beta-thalassemia mutations in India.

We have characterized the mutations in 1050 carriers of the beta-thalassemia gene and analyzed their regional distribution in India. The majority of beta-thalassemia carriers were migrants from Pakistan and their pattern of mutations differed from the rest. The frequency of the 619-bp deletion was 33.3% among the migrants from Pakistan, 8-17% in the northern states, and less than 5% in the other states. Among non-migrant subjects, the predominant mutation was IVS-I-5 (G-->C), varying from 85% in the southern states and 66-70% in the eastern states to 47-60% in the northern states. The mutation IVS-I-1 (G-->T) was observed at high frequency among the migrants from Pakistan (26.2%), but with very low/zero frequency in the other states. Mutations at codons 8/9 (+G) and codons 41/42 (-CTTT) were distributed in all regions of India with a frequency varying from 3% to 15%. Only eight of 12 published rare mutations were observed in subjects from different parts of India. Mutations of codon 5 (-CT) and codons 47/48 (+ATCT) were found exclusively in migrants from Pakistan, and mutation -88 (C-->T) was detected only in subjects from Punjab, Haryana, and Uttar Pradesh. Using the amplification refractory mutation system technique, mutations were successfully identified in 98.2% of subjects. Overall, 91.8% of the subjects had one of the five commonest mutations [IVS-I-5 (G-->C), 34.1%; 619-bp deletion, 21.0%; IVS-I-1 (G-->T) 15.8%; codons 8/9 (+G), 12.1%, and codons 41/42 (-CTTT), 8.7%], 5.9% of the subjects had a less common mutation, while 1.8% of the carriers remained uncharacterized. The application of this knowledge has helped to successfully establish a program of genetic counselling and prenatal diagnosis of beta-thalassemia in order to reduce the burden of this disease in India.

Codon↗
PubMed1997

A comparison of ambulatory care and selected procedure rates in the health care systems of the Province of Manitoba, Canada; Kaiser Permanente Health Maintenance Organization; and the United States.

To determine if there are differences in physician services in different health care systems, we compared ambulatory visit rates and procedure rates for three surgical procedures in the province of Manitoba, Canada; Kaiser Permanente Health Maintenance Organization; and the United States. The KP system, with its single payer and low financial barriers, is not unlike the Canadian system. But, for most of the United States, the primary payment mechanism is fee-for-service, with the patient paying a significant amount, thereby militating against preventive and early primary care. Manitoba and KP data were extracted from computerized administrative records. U.S. data were obtained from publicly available reports. Manitoba provides 1.8 times and KP 1.2 times (1.4 when allied health visits are included) as many primary care physician visits as the United States. For the surgical procedures studied, U.S. rates were higher than those in either the KP HMO or in Manitoba. We conclude that (1) the U.S. system leads to more surgical intervention, and (2) removal of financial barriers leads to higher use of primary care services where more preventive and ameliorative care can occur.

Ambulatory Care↗
PubMed1997

Effects of subpopulation structure on probability calculations of DNA profiles from forensic PCR analysis.

DNA typing for forensic identification is a two-step process. The first step involves determining the profiles of samples collected at the crime scene and comparing them with the profiles obtained from suspects and the victims. In the case of a match that includes the suspect as the potential source of the material collected at the crime scene, the last step in the process is to answer the question, what is the likelihood that someone in addition to the suspect could match the profile of the sample studied? This likelihood is calculated by determining the frequency of the suspect's profile in the relevant population databases. The design of forensic databases and the criteria for comparison has been addressed by the NRC report of 1996 (National Research Council, 1996). However, the fact that geographical proximity, migrational patterns, and even cultural and social practices have effects on subpopulation structure establishes the grounds for further study into its effects on the calculation of probability of occurrence values. The issue becomes more relevant in the case of discrete polymorphic markers that show higher probability of occurrence in the reference populations, where several orders of magnitude difference between the databases may have an impact on the jury. In this study, we calculated G values for all possible pairwise comparisons of allelic frequencies in the different databases from the races or subpopulations examined. In addition, we analyzed a set of 24 unrelated Caucasian, 37 unrelated African-American, and 96 unrelated Sioux/Chippewa individuals for seven polymorphic loci (DQA1, LDLR, GYPA, HBGG, D7S8, GC, and D1S80). All three sets of individuals where sampled from Minnesota. The probability of occurrence for all seven loci were calculated with respect to nine different databases: Caucasian, Arabic, Korean, Sioux/Chippewa, Navajo, Pueblo, African American, Southeastern Hispanic, and Southwestern Hispanic. Analysis of the results demonstrated marked differences in the probabilities of occurrence when individuals were compared to the different populations and subpopulation databases. The possible genetic and forensic consequences of subpopulation structure on probability calculations are discussed.

DNA Fingerprinting↗
PubMed1997

Differentiation of Helicobacter pylori strains directly from gastric biopsy specimens by PCR-based restriction fragment length polymorphism analysis without culture.

Recent studies have shown the usefulness of PCR-based restriction fragment length polymorphism (RFLP) analysis for differentiating Helicobacter pylori strains isolated by culture. For this study, a PCR-based RFLP assay was developed for directly typing H. pylori strains from gastric biopsy specimens. Nineteen gastric biopsy specimens obtained from patients undergoing endoscopy for gastrointestinal complaints were cultured for isolation of H. pylori. Genomic DNA preparations from these gastric biopsy specimens and the corresponding H. pylori isolates were tested by our PCR-based RFLP assay. The 1,179-bp H. pylori DNA fragments amplified by the PCR assay were digested with the restriction enzymes HhaI, MboI, and AluI and analyzed by agarose gel electrophoresis. HhaI, MboI, and AluI digestion produced 11, 10, and 6 distinguishable digestion patterns, respectively, from the 19 H. pylori isolates tested and generated 13, 11, and 6 different patterns, respectively, from the 19 gastric biopsy specimens. The patterns from 13 of the 19 gastric biopsy specimens matched those of the H. pylori isolates from the corresponding patients. The patterns from the remaining six biopsy specimens appeared to represent infection by two strains of H. pylori; the pattern of one strain was identical to that of the isolate from the corresponding patient. By combining all the restriction enzyme digestion patterns obtained by using HhaI, MboI, and AluI, we observed 19 distinct RFLP patterns from the 19 specimens. The results suggest that the PCR-based RFLP analysis method may be useful as a primary technique to identify and distinguish H. pylori strains directly from gastric biopsy specimens without culture of the organisms.

Bacterial Typing Techniques↗
PubMed1997

A comparison of antiemetic efficacy of droperidol alone and in combination with metoclopramide in day surgery anaesthesia.

We have studied the antiemetic efficacy of droperidol alone, and in combination with metoclopramide in first trimester termination of pregnancy in day surgery. The aim was to determine whether the addition of metoclopramide could further reduce the incidence of postoperative nausea and vomiting (PONV) but avoid excessive sedation. Group I (control, n = 40) received i.v. droperidol 0.625 mg at induction. Group II (study, n = 40) received i.v. droperidol 0.625 mg and i.v. metoclopramide 10 mg at induction. The incidence of nausea at 1 and 2 hours postoperatively was 23% and 10% in group I, and 5% and nil in group II respectively. The difference in the incidence of nausea was significant at p < 0.05 at one hour but not at two hours postoperatively. No patients vomited. There was no difference in the sedation and pain score between them. We did not observe any significant side effects attributable to either drug. All patients were discharged home within 3 hours. We conclude that in the prevention of PONV, the combination of metoclopramide and droperidol is superior to the use of droperidol alone at one hour but not at two hours postoperatively.

Adult↗
PubMed1997

Sedation for the conduct of lumbar epidural anaesthesia: a study using subanaesthetic dose of ketamine in combination with midazolam.

We gave sedation for the conduct of lumbar epidural analgesia using intravenous ketamine 0.3 mg.kg-1 with intravenous midazolam 2 mg. Forty adult Chinese females undergoing major gynaecological laparotomies had epidural catheter inserted before general anaesthesia, 20 of whom were given ketamine and midazolam (study group) and the other 20 acted as control. During the conduct of the epidural, the pain and anxiety scores in the study group were significantly less than the control group (P < 0.05). Patients were significantly more sedated in the study group (P < 0.05). All the patients in the study group were satisfied and would consent to future epidural versus 75% in the control group (significant at P < 0.05). Ninety per cent of patients in the study group had amnesia but none in the control group. Pain experienced during the epidural was the reason for refusal of future epidural. We did not observe any emergence phenomenon or cardiovascular stimulation. There was a statistically significant decrease in the pulse oximetry oxygen saturation (SpO2) in the study group but none required oxygen supplementation. We concluded that pain caused by the conduct of epidural did decrease the patient's acceptance rate to future epidural, and the combined use of intravenous ketamine 0.3 mg.kg-1 and midazolam 2 mg provided adequate sedation, analgesia, anxiolysis and amnesia to significantly increase the acceptance rate without any significant side effects.

Adult↗
PubMed1997

CD30-ligand and CD40-ligand expression in lymph nodes involved with Hodgkin's disease.

BACKGROUND: Reed-Sternberg cells of Hodgkin's disease express CD30 and CD40 receptors. The ligands for these receptors have been reported to have pleiotropic biologic activities in vitro, including induction of cell death and enhancing cell survival. Co-expression of the ligands for these receptors in lymph nodes involved with Hodgkin's disease is not known. PURPOSE: The purpose of this study was to examine CD30 ligand (L) and CD40L expression in lymph nodes of patients with Hodgkin's disease, and to study CD30L expression on nodal lymphocyte subsets. MATERIALS AND METHODS: CD30L expression on subsets of lymphocytes of five lymph nodes involved with Hodgkin's disease was determined by two-color FACScan. Messenger RNA expression of CD30L and CD40L was determined by the reverse-transcriptase polymerase chain reaction (RT-PCR) method performed on seven specimens involved with Hodgkin's disease (five lymph nodes and two spleens). RESULTS: Four of seven specimens (57%) contained cells that expressed CD30L mRNA and three specimens (43%) contained CD40L-expressing cells. The mean percentage of nodal lymphocytes expressing CD30L surface protein was < or = 20%. CONCLUSION: Hodgkin's disease lymph nodes and spleens frequently lack CD30L- and CD40L-expressing cells, and when CD30L is expressed, it is usually detected on few numbers of lymphocytes. The balance in the level of expression of these ligands in Hodgkin's disease lymph nodes may be related to the disease's clinical behavior.

CD40 Antigens↗
PubMed1997

Combination of suppository diclofenac and intravenous morphine infusion in post-caesarean section pain relief--a step towards balanced analgesia?

UNLABELLED: Post-Caesarean section analgesia can be achieved by morphine infusion. NSAIDs are frequently administered to relieve uterine cramps. This study is aimed at assessing the efficacy of the combination of suppository diclofenac and morphine infusion in post-Caesarean section pain relief. General anaesthesia was given to 60 patients who were randomly allocated into two groups: group A received 100 mg suppository diclofenac before surgical incision and morphine infusion 1.5 mg per hour postoperatively while group B received only morphine infusion 1.5 mg/H postoperatively. Pain assessment was done by an unbiased observer on arrival of the patients in the recovery room, then 6 hours, 12 hours and 24 hours later. Pain relief was found to be better in group A, with group B requiring more supplemental analgesia. Apart from better analgesic effect for wound pain, group A also had more favourable scores for uterine cramping pain. The incidence of nausea or vomiting was similar in both groups. No respiratory depression was observed in both groups. Two cases of increased bleeding (one from each group) were observed, both receiving conservative treatment. THE CONCLUSION: suppository diclofenac improved the analgesic efficacy of morphine infusion in post-Caesarean analgesia.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1997

Detection of beta-thalassaemia mutation insertion ATCT at codon 47/48 by ARMS technique for screening & prenatal diagnosis.

We report the diagnosis of the newly identified mutation codon 47/48 insertion ATCT using allele specific primers by the PCR-based amplification refractory mutation system (ARMS). Using this method prenatal diagnosis was provided to five couples at risk for this mutation. The assay provides an easy, non-isotopic method for identifying this mutation in cases which remain uncharacterized after screening for the 5 'common' and 12 'rare' Indian mutations. It will be useful for screening and prenatal diagnosis in at risk couples and help in the thalassaemia control programme in India.

Codon↗
PubMed1996

Prevalence of gastroesophageal reflux in patients who develop pneumonia following percutaneous endoscopic gastrostomy: a 24-hour pH monitoring study.

Percutaneous endoscopic placement of feeding gastrostomies (PEG) was pioneered by Gauderer et. al. in 1980 [1]. Since then, it has become the preferred method of providing enteral nutritional support in children and adults because of advantages in morbidity and cost [2,3]. Pneumonia is a known sequel of this procedure, occurring at different rates, depending on the length of follow-up. Some series have shown an incidence of 10% at 30 days and others 56% at 11 months [4,5]. It does not appear that PEG feeding offers an advantage over the more traditional naso-enteric tube feeding methods in this respect. To study the prevalence of gastroesophageal reflux (GER) in PEG-fed patients, we quantitated GER by 24-hour intraesophageal pH monitoring in a group of patients who developed post-PEG pneumonia and compared it with a control group. Our study demonstrates an increased prevalence of GER in the pneumonia group compared with the control group. However, the exact contribution of this observed increased GER to the development of pneumonia needs to be determined.

Adult↗
PubMed1996

A newly developed PCR assay of H. pylori in gastric biopsy, saliva, and feces. Evidence of high prevalence of H. pylori in saliva supports oral transmission.

We have recently developed a new PCR assay for the detection of H. pylori. In this study, the polymerase chain reaction (PCR) assay was used to detect H. pylori in 88 gastric biopsy, 85 saliva, and 71 fecal specimens from 88 patients. H. pylori infection was confirmed in 71 of 88 patients by culture and/or histological stain of gastric biopsies. Serum IgG antibody to H. pylori was also measured and resulted in 97% sensitivity and 94% specificity. H. pylori DNA was detected by the PCR assay in gastric biopsy specimens from all 71 patients (100% sensitivity) with proven gastric H. pylori infection but not from 17 noninfected patients (100% specificity). In saliva specimens, H. pylori DNA was identified in 57 of the 68 patients (84%) with proven gastric H. pylori infection and in three of the 17 patients without gastric H. pylori infection. However, the PCR assay was only able to detect H. pylori DNA in the feces from 15 of 61 patients (25%) with proven gastric H. pylori infection and one of the 10 patients without gastric H. pylori infection. The results show that the PCR assay is reliable for detecting the presence of H. pylori in gastric biopsy and saliva specimens. The data indicate that H. pylori exists in a higher prevalence in saliva than feces and that the fecal-oral route may be an important means of transmission of this infection in developing countries but not as significant as previously suspected in the developed countries. It is likely that the oral-oral route is more prominent.

Antibodies, Bacterial↗
PubMed1996

Psychosocial factors and chronic pelvic pain: a comparison of women with endometriosis and with unexplained pain.

Chronic pelvic pain is a common clinical problem, and physical investigation often fails to reveal its cause. For this reason, it has been argued that psychological and social factors contribute to such "unexplained" pain. Few studies to date using well-validated psychometric measures and adequate sample sizes have compared patients with unexplained pain and those with identified physical disease. The present study compared pain severity, mood symptoms, personality characteristics and social adjustment in women with unexplained pain and women with endometriosis. Women with endometriosis were more likely to come from upper socioeconomic groups. No differences in mood symptoms or personality characteristics were identified, but women with endometriosis had somewhat more severe pain and greater social dysfunction than those with unexplained pain. Mood disorder and social dysfunction appear to be at least as important in patients with proven endometriosis as in those with unexplained pain.

Adult↗
PubMed1996

Influence of previous pain experience on the episode incidence of low back pain: results from the South Manchester Back Pain Study.

BACKGROUND: A pathological cause cannot be identified for most new episodes of low back pain (LBP) presenting to the general practitioner. One important potential influence on susceptibility is previous pain experience. To accurately investigate the contribution of this phenomenon to the onset of new episodes of LBP a prospective population study is required. AIMS: To determine the relationship of prior pain in the back and other musculoskeletal sites to risk of subsequent new episodes of LBP. METHODS: The population studied included all 2715 adults from the South Manchester Back Pain Study who were free of LBP during the month prior to the baseline survey. At baseline a detailed musculoskeletal pain history was obtained. New episodes of LBP over the subsequent 12 months were ascertained by: (i) prospectively monitoring all primary care consultations in the study cohort (consulting episodes) and (ii) a follow-up survey after 1 year to determine new episodes during that 12-month period not leading to consultation (non-consulting episodes). RESULTS: The 12-month cumulative incidence of new consulting episodes was 3% in males and 5% in females, and for new non-consulting episodes 31% in males and 32% in females. Those with a history of previous LBP had twice the rate of new episodes, both consulting and non-consulting, compared to those with no LBP in the past. Neck pain or pain in other musculoskeletal sites at baseline also doubled the risk of a subsequent new episode of LBP. Adjusting for psychological distress and the other pain variables had little influence on the findings. CONCLUSION: In those currently free of LBP a previous history of the symptom substantially increases the risk of a further episode, with pain in other sites an equally strong independent predictor of subsequent LBP.

Adolescent↗
PubMed1996

CD30 ligand is expressed on resting normal and malignant human B lymphocytes.

CD30, a member of the tumour necrosis receptor superfamily, is physiologically expressed on a subpopulation of T helper cells in normal individuals but is also expressed on several malignant and virally transformed cells. Its ligand (CD30L) is a pleiotropic cellular transmembrane protein that can induce cell death in several CD30+ cell lines. CD30L expression has been reported on activated human peripheral blood T lymphocytes and macrophages but not on B cells. Here we show that the CD30L is expressed on resting normal and on malignant B cells in addition to both CD4+ and CD8+ subsets of activated T cells, making it the second tumour necrosis family member, in addition to the CD27 ligand, that can be expressed on both T and B cells. These findings raise the possibility that the CD30L has a role in B-cell/T-cell communication and that B and T cells are likely to be involved in the growth regulation of CD30+ tumours.

B-Lymphocytes↗
PubMed1996

Molecular basis of neuronal biorhythms and paroxysms.

The molecular basis of the biorhythms are evoked in relation to cerebral EEG rhythms and paroxysms. Basic oscillatory phenomena have been well shown and modeled in systems such as the glycolytic pathway, the oscillations of cAMP in amoebas and rhythms of the intracellular cycline during mitosis. In excitable cells the intracellular calcium and cAMP oscillations exhibit a signalling system with many advantages. Thus the question arises: to what extent can the EEG paroxysms observed in epileptic syndrome be due to disturbances in such basic molecular pathways that underlie intracellular molecular oscillations? The usefulness of the absence-rat-model and the implication the T type Ca(2+)-channel of the thalamic nuclei in the pathophysiology of this epileptic syndrome are discussed.

Amoeba↗