Search PubMed⌕ Search

Biomedical subjects

S Ramcharan

Publications and source records attributed to S Ramcharan.

At least 19 recordsLinked to original sources
PubMed1998

Survival after massive ecstasy overdose.

INTRODUCTION: The toxicity profile of the amphetamine derivative 3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy") is well known. This designer drug is usually taken at "house parties" and may cause severe complications, sometimes leading to death, even when taken in relatively small units (1 or 2 tablets). Up to now, only a few cases of survival after ingestion of an overdose of Ecstasy have been described. In most cases the users developed hyperthermia, disseminated intravascular coagulation, rhabdomyolysis, and renal failure. CASE REPORT: We describe a man who, after ingesting 50 tablets of Ecstasy (in combination with oxazepam and alcohol) at home, recovered within 2 days. Presenting features were unconsciousness, apnea, and convulsions. It is suggested that in most cases severe 3,4-methylenedioxymethamphetamine toxicity results from an interaction between direct pharmacological effects of the drug and the prevailing environmental conditions (high ambient temperature, dancing in trance, little fluid intake).

Adult↗
PubMed1995

The relationship between chinook conditions and women's physical and mental well-being.

The objective of this study was (1) to determine the relationship between chinook conditions and physical and psychological symptoms in women aged 20-49 years, and (2) to examine the possibility of subgroups of chinook-sensitive women. The evidence for this relationship is at present merely anecdotal. The study carried out in 1985-1986 in Calgary comprises the secondary analysis of a large survey of various health and health-related factors, including different symptoms, of urban women aged 20-49 years. The interview date was used to link these data to days on which pre-chinook, chinook, post-chinook and non-chinook conditions occurred. Between November 1, 1985 and February 28, 1986, 182 women were interviewed on pre-chinook days, 74 on chinook days, 229 on post-chinook days and 886 on non-chinook days. Autonomic reactions and skin disorders were found to be significantly related to chinook conditions. None of the psychological symptoms was related to chinook conditions. However, a significant relationship was found between symptoms and chinook conditions in women with a history of emotional disorders. This type of information is important to educate chinook-sensitive women and health professionals as well as for hospital emergency departments in order to be able to prepare for potential increases in workload.

Acclimatization↗
PubMed1995

The relationship between chinook conditions and women's illness-related behaviours.

The objective of this study was to (1) to describe the relationship between chinook conditions and illness related behaviour in women, aged 20-49 years, and (2) to examine the possibility of the existence of subgroups of chinook-sensitive women. At present no empirical evidence is available regarding a relationship between chinook conditions and illness related behaviours. This study comprises the secondary analysis of a large survey of various health and health-related factors of urban women aged 20-49 years, carried out in 1985-1986 in Calgary. The interview date was used to link behaviours to chinook conditions. We found no evidence of a significant relationship between the behaviours investigated and chinook conditions in the general population. However, the data strongly supported the concept of chinook sensitivity. Women with a history of chronic health problems were more likely to visit a health care professional on chinook days than healthy women and women in the subgroup aged less than 35 years cut down their usual daily activities during chinook conditions. Women with a history of recurring migraine headaches were less likely to take prescription medication on chinook days, and women with a history of emotional disorders were more likely to have higher scores on the accident scale and to report bursts of energy or excitement during chinook days. More research is needed to identify subgroups of susceptible persons, as well as to determine whether chinook sensitive persons are equally susceptible to weather changer of other types.

Adult↗
PubMed1993

Substrate length requirements for efficient mitotic recombination in Saccharomyces cerevisiae.

An ectopic recombination system using ura3 heteroalleles varying in size from 80 to 960 bp has been used to examine the effect of substrate length on spontaneous mitotic recombination. The ura3 heteroalleles were positioned either on nonhomologous chromosomes (heterochromosomal repeats) or as direct or inverted repeats on the same chromosome (intrachromosomal repeats). While the intrachromosomal events occur at rates at least 2 orders of magnitude greater than the corresponding heterochromosomal events, the recombination rate for each type of repeat considered separately exhibits a linear dependence on substrate length. The linear relationships allow estimation of the corresponding minimal efficient processing segments, which are approximately 250 bp regardless of the relative positions of the repeats in the yeast genome. An examination of the distribution of recombination events into simple gene conversion versus crossover events indicates that reciprocal exchange is more sensitive to substrate size than is gene conversion.

Base Sequence↗
PubMed1992

Effect of oral contraceptive use on reoperation following surgery for Crohn's disease.

The influence of oral contraceptive (OCP) use as a risk factor for the development of Crohn's disease is disputed. We wished to determine if OCP use affected the risk of recurrence (defined as need for a second surgery) in women who had already undergone a resection for Crohn's disease. We hypothesized that if contraceptive use was a risk factor for disease development, it could influence recurrence. Using a mail questionnaire, we surveyed 138 women regarding their OCP use following surgery for Crohn's disease. All participants were between ages 16 and 35 at the time of their initial surgery which occurred between 1966 and 1984. Ninety-seven women (70%) responded. Mean follow-up was 9.9 years (range 4-27). Forty-six women required a second surgery. The recurrence rate as determined by actuarial analysis, was 27.2% (95% confidence intervals (CI95 16.5-38.1) and 58.0% (CI95 37.8-78.2) at 5 and 10 years, respectively. Thirty-two women took OCP in the first year following surgery. Eleven OCP users (34.4%) required additional surgery compared to 34 (53.1%) of nonusers. Using life table analysis, the percentage requiring a second surgery was 25.0% (CI95 6.9-43.1) and 40.7% (CI95 1.5-80%) at 5 and 10 years, respectively, for users compared to 28.4% (CI95 6.9-43.1) and 64.0% (CI95 40.5-87.5) for nonusers (Lee Desu, P greater than 0.05). When surveyed about their reasons for using OCP, most women stated that their disease did not affect their decision to use contraceptives.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

The epidemiology of premenstrual symptoms in a population-based sample of 2650 urban women: attributable risk and risk factors.

This epidemiologic survey achieved a reliable measure of the prevalence of premenstrual symptoms by avoiding the biases of small or selected samples, anamnestic error, and subjective expectation. From 6232 women (a 78.8% response), aged 20-49 years, identified through a random sample of urban households, the 24-hour prevalence of symptoms was obtained using the Moos' Menstrual Distress Questionnaire, administered without reference to the menstrual cycle. For 71% of the naturally cycling women, current cycle phase was determined by follow-up (n = 2650); but a higher prevalence of severe or moderately severe affective symptoms in the premenstrual compared to the mid-cycle phase was not found. However, observed risk factor interactions led to the conclusion that premenstrual distress is a discrete mood disorder, affecting women aged 25-35 years, with probable ovulatory cycles, and vulnerable to stress; and that the risk of affective symptoms attributable to the premenstrual state was one percent.

Adult↗
PubMed1990

Effect of cigarette smoking on recurrence of Crohn's disease.

The effect of cigarette smoking on recurrence (defined in this study as the need for repeat surgery) in patients who had previously required surgery for Crohn's disease was assessed in a historical cohort of 174 patients. Mean follow-up was 10.8 yr. The 5- and 10-yr recurrence rates were 28% and 56%, respectively. Five- and 10-yr rates were significantly different for smokers (36%, 70%) and nonsmokers (20%, 41%). When patients were stratified by gender, the increased risk was more apparent in women (odds ratio 4.2, 95% confidence interval 2.0-4.2) than in men (odds ratio 1.5, 95% confidence interval 0.8-6.0). Evidence for a dose-response relationship could be identified in women but not men. Cigarette smoking may not only be a risk factor for development of Crohn's disease but also may influence disease activity following surgery.

Alberta↗
PubMed1989

Cancer mortality of Chinese in Canada.

Cancer deaths determined from national vital statistics in Canadian ('Chinese') immigrants who were born in mainland China, Hong Kong or Taiwan were compared with those in the Canadian-born population. Standardized mortality ratios (SMR) based on 1981 census data and on 755 deaths among 81,740 Chinese males and 586 deaths among 83,965 females during 1980-1984, showed that the overall cancer mortality in Chinese males (SMR 141), and females (SMR 116), was significantly higher than in the Canadian-born. Moreover, SMR varied by cancer site and showed a pattern of risks similar to those reported for foreign-born Chinese in the USA: strikingly high SMR for nasopharynx and liver or gallbladder in males and females; high ratios for stomach, intestines or colon, rectum, and lung, but a low ratio for prostate in males; and high ratios for lung and cervix uteri but low ratios for breast and ovary in females. These findings indicate that useful studies on cancer mortality could be carried out in Canadian Chinese.

Adolescent↗
PubMed1985

Chromosomal abnormalities in the Kaiser-Permanente Birth Defects Study, with special reference to contraceptive use around the time of conception.

Chromosomal abnormalities were studied in 33,551 abortions and births to women whose contraceptive histories had been recorded at their first antenatal visit in 1975-1977. Chromosome examinations were performed exclusively on clinical grounds. There were 45 de novo abnormalities detected (1.34/1,000); three of them were detected at amniocentesis. Trisomy 21 was observed in 27 cases (0.80/1,000), trisomy 18 in nine (0.27), other trisomies in three (0.09), and translocations or deletions in five (0.15). One case of triploidy and six cases of inherited abnormalities were detected. There were no significant racial variations. No increase in risk for chromosomal abnormalities was found among women who had used oral contraceptives prior to becoming pregnant or among women who experienced oral contraceptive breakthrough pregnancies. Two cases of trisomy 18 were observed among the 814 deliveries following oral contraceptive breakthrough conceptions (2.46/1,000), two cases of trisomy 21 occurred in 338 births following failures of rhythm contraception (5.92/1,000), and no cases of trisomy 21 or 18 among the 1,569 women using spermicides at the time of conception.

Abnormalities, Drug-Induced↗
PubMed1985

Congenital abnormalities in the offspring of women who used oral and other contraceptives around the time of conception.

Congenital malformations were observed in 33,545 newborns whose mothers were questioned during pregnancy about contraceptives used around the time of conception. There were 597 babies (17.8/1,000) with major malformations and 4,046 (120.6/1,000) with minor ones. The 8,522 offspring of mothers who had used oral contraceptives (OC) prior to conception showed 17.2/1,000 major malformations compared with rates of 15.0 and 20.1/1,000 in the groups who had used other methods or no birth control prior to conception. There was no evidence for an increased risk of malformations in women conceiving within 1 month of stopping OC. There were 850 babies exposed to OC in utero and the ratio of observed to expected cases of major malformations was 1.24 (n.s.) if the mother was a nonsmoker and 2.98 (P = 0.028) if the mother smoked one pack or more of cigarettes daily. There were no significant changes in malformation rates following failures of intrauterine devices, spermicides or rhythm contraception.

Abnormalities, Drug-Induced↗
PubMed1982

Sex of offspring of women using oral contraceptives, rhythm, and other methods of birth control around the time of conception.

Sex ratios were studied in a cohort of 33,205 newborns whose mothers had been questioned in early pregnancy about contraceptive use around the time of conception., The proportion of males was 0.517 (95% confidence limits [CL], 0.512 to 0.522). In the 9279 offspring of women who had used oral contraceptives (OC) in the 5 months prior to conception the sex ratio was 0.517 (0.507 to 0.527). There are sufficient numbers available for study for us to be 95% certain that OC causes no shift in sex ratio of 1% or more. Women who conceived within 2 months of stopping the pill had a small excess of males (0.528; 95% CL, 0.510 to 0.546), but this excess was probably due to chance. OC failures were followed by a raised sex ratio in the offspring (0.543; 95% CL, 0.509 to 0.577), and this excess of males was observed consistently in subgroups of maternal age, parity, race, and education. Failures of rhythm contraception were also associated with a consistent excess of male births (0.567; 95% CL, 0.514 to 0.620). No changes were observed after failures of IUDs, barrier, or chemical methods.

Adult↗
PubMed1980

Spontaneous foetal losses in women using different contraceptives around the time of conception.

Spontaneous losses between the 5th and 27th weeks of pregnancy were measured in a prospective study of 32 123 women whose contraceptive history around the time of conception was known. Diaphragm use prior to conception was associated with a significant reduction in second-trimester losses, after taking into account the effects of age, parity, race, marital status, alcohol use, and previous spontaneous or induced abortions. Women who used oral contraceptives and stopped them more than one month prior to their LMP experienced a deficit of first-trimester losses but conceptions occurring immediately after stopping the pill were followed by a small but nonsignificant increase in spontaneous abortions. After oral contraceptive failures there was an increase in first-trimester losses, but no change in the incidence of second-trimester ones. IUD failures were followed by a significant two-fold increase in the risk of both first and second-trimester losses: no differences were detected between the different brands.

Abortion, Spontaneous↗
PubMed1979

A prospective study of spontaneous fetal losses after induced abortions.

The incidence of spontaneous abortions was observed among 31,917 women followed from their first prenatal visit. Life-table analysis showed that losses in the first trimester were not significantly affected by previous induced abortions, nor was any change in the risk of second-trimester losses detected among the 1493 parous women who reported having had induced abortions after childbirth. There was, however, an increase in the incidence of midtrimester losses among the 2019 nulliparous women with previous induced abortions; the age-adjusted rate of loss was 59.9 per 100,000 women at risk per day, as compared with 24.2 among the 12,042 control nulliparous women (P less than 0.001). The relative risk increased with the number of previous induced abortions and was not explained by the distribution of demographic and social variables. The risk decreased from 3.27 (95 per cent confidence limits, 1.72 to 6.23) after abortions induced before 1973, mainly by dilation and curettage, to 1.42 (0.76 to 2.65) after those done since 1973, when the more gentle technic of cervical dilation by use of laminaria was introduced. These findings indicate that there is little or no risk of spontaneous abortions after induced abortions when performed by current technics.

Abortion, Induced↗
PubMed1979

Risk of vascular disease in women. Smoking, oral contraceptives, noncontraceptive estrogens, and other factors.

We investigated the relation in women of various factors to risk of myocardial infarction, subarachnoid hemorrhage, other strokes, and venous thromboembolism. Smoking significantly increased risk of all four diseases, whereas oral contraceptive use was associated with an increase only in risk of subarachnoid hemorrhage and venous thromboembolism. Use of noncontraceptive estrogens was not associated with increased risk of any of these diseases. Hypertension, hypercholesterolemia, obesity, gallbladder disease, and nondrinking of alcohol were all associated with increased risk of myocardial infarction, whereas only hypertension and hypercholesterolemia were associated with increased risk of other strokes. Cigarette smoking was overwhelmingly the most important risk factor for vascular disease in women. Smoking should be considered a contraindication to oral contraceptive use, or at the very least, women wishing to use oral contraceptives should be strongly urged not to smoke.

Adolescent↗
PubMed1979

Use of contraceptives prior to and after conception and exposure to other fetal hazards.

In a large prospective study, set up to determine whether reproductive outcomes are affected by prior contraceptive use, 34,344 women were recruited at their first antenatal visit and followed until pregnancy termination. This paper summarizes the study methods and describes the demographic differences between subjects who used various contraceptives shortly before conception, and those who experienced contraceptive failures. Thirty percent of the women had used oral contraceptives (OCs) during the 5 months prior to conception and 2.4% had continued using them after their LMP. IUDs had been used by 5.8% of women before conception and 1.1% after. If these rates are also true for the whole population of the U.S., they indicate that approximately 70,000 babies are born each year following pill-failures and 30,000 following failures of IUD's. Exposure to other fetal hazards was common, with 48% of pregnant women drinking alcohol, 28% smoking, and 15% receiving diagnostic X-rays. OC use was more common among smokers and drinkers, and OC failures were significantly associated with the use of anti-epileptics, aspirin, and with exposure to radiation.

Adult↗
PubMed1978

Serum high-density-lipoprotein cholesterol in women using oral contraceptives, estrogens and progestins.

To determine the associations between high-density-lipoprotein cholesterol levels and use of oral contraceptives or of noncontraceptive estrogens and progestins we analyzed the serum levels of this lipid in 4978 women, 21 to 62 years of age. In estrogen users, the mean level was 6.7 to 15.1 mg per deciliter above the nonuser level (P less than 0.001), whereas in a group of progestin users it was 15.8 mg per deciliter below (P less than 0.001). In women using combination oral contraceptives, the level varied with the type and dose of the component steroids, in general increasing with increasing dose of estrogen and decreasing with increasing dose or potency of progestin. Thus, the net effect of use of a combination oral contraceptive on high-density-lipoprotein cholesterol depends on its formulation.

Adult↗