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Biomedical subjects

A Langer

Publications and source records attributed to A Langer.

At least 37 records · Page 2Linked to original sources
PubMed2000

Primary fallopian tube carcinoma with isolated torsion of involved tube.

BACKGROUND: Primary fallopian tube carcinoma (FTC) is an aggressive but rare tumor. Worldwide, more than 1,500 cases have been published, and about 20 new cases are added every year. Isolated fallopian tube torsion (IFTT) is an unusual and uncommon event. CASE: We report a 69-year-old Caucasian woman, Gravida 4, Para 3, with a long history of hypertension, diabetes mellitus with retinopathy and neuropathy, and history of extensive coronary artery disease, for which a triple-by-pass graft was performed. She was placed on anticoagulation therapy. Subsequently, she developed intermittent vaginal bleeding. RESULTS: We reviewed and discussed the symptoms and work-up of the patient in detail. She underwent exploratory laparotomy, and primary FTC with isolated torsion of the involved fallopian tube was diagnosed. Peritoneal washings, omentectomy, total abdominal hysterectomy and bilateral salpingo-oophorectomy were performed. CONCLUSION: Review of the English literature on the presenting symptoms and diagnostic management of primary FTC and IFTT is presented.

Adenocarcinoma↗
PubMed1999

Single-bolus tenecteplase compared with front-loaded alteplase in acute myocardial infarction: the ASSENT-2 double-blind randomised trial.

BACKGROUND: Bolus fibrinolytic therapy facilitates early efficient institution of reperfusion therapy. Tenecteplase is a genetically engineered variant of alteplase with slower plasma clearance, better fibrin specificity, and high resistance to plasminogen-activator inhibitor-1. We did a double-blind, randomised, controlled trial to assess the efficacy and safety of tenecteplase compared with alteplase. METHODS: In 1021 hospitals, we randomly assigned 16,949 patients with acute myocardial infarction of less than 6 h duration rapid infusion of alteplase (< or = 100 mg) or single-bolus injection of tenecteplase (30-50 mg according to bodyweight). All patients received aspirin and heparin (target activated partial thromboplastin time 50-75 s). The primary outcome was equivalence in all-cause mortality at 30 days. FINDINGS: Covariate-adjusted 30-day mortality rates were almost identical for the two groups--6.18% for tenecteplase and 6.15% for alteplase. The 95% one-sided upper boundaries of the absolute and relative differences in 30-day mortality were 0.61% and 10.00%, respectively, which met the prespecified criteria of equivalence (1% absolute or 14% relative difference in 30-day mortality, whichever difference proved smaller). Rates of intracranial haemorrhage were similar (0.93% for tenecteplase and 0.94% for alteplase), but fewer non-cerebral bleeding complications (26.43 vs 28.95%, p=0.0003) and less need for blood transfusion (4.25 vs 5.49%, p=0.0002) were seen with tenecteplase. The rate of death or non-fatal stroke at 30 days was 7.11% with tenecteplase and 7.04% with alteplase (relative risk 1.01 [95% CI 0.91-1.13]). INTERPRETATION: Tenecteplase and alteplase were equivalent for 30-day mortality. The ease of administration of tenecteplase may facilitate more rapid treatment in and out of hospital.

Aged↗
PubMed1999

Rapid and efficient cloning of proviral flanking fragments by kanamycin resistance gene complementation.

We have developed a technique for the rapid cloning of unknown flanking regions of transgenic DNA. We complemented a truncated kanamycin resistance gene of a bacterial plasmid with a neomycin resistance gene fragment from a gene transfer vector. Optimized transformation conditions allowed us to directly select for kanamycin-resistant bacteria. We cloned numerous proviral flanking fragments from growth factor-independent cell mutants that were obtained after infection with a replication incompetent retroviral vector and identified integrations into the cyclin D2 and several unknown genomic sequences. We anticipate that our method could be adapted to various vector systems that are used to tag and identify genes and to map genomes.

Cloning, Molecular↗
PubMed1999

Emergency contraception in Mexico City: what do health care providers and potential users know and think about it?

Emergency contraception promises to reduce Mexico's high unwanted pregnancy and unsafe abortion rates. Because oral contraceptives are sold over-the-counter, several emergency contraceptive regimens are already potentially available to those women who know about the method. Soon, specially packaged emergency contraceptives may also arrive in Mexico. To initiate campaigns promoting emergency contraception, we interviewed health care providers and clients at health clinics in Mexico City, ascertaining knowledge, attitudes, and practices concerning the method. We found limited knowledge, but nevertheless cautious support for emergency contraception in Mexico. Health care providers and clients greatly overestimated the negative health effects of emergency contraception, although clients overwhelmingly reported that they would use or recommend it if needed. Although providers typically advocated medically controlled distribution, clients believed emergency contraception should be more widely available, including in schools and vending machines with information prevalent in the mass media and elsewhere.

Adolescent↗
PubMed1999

How do researchers influence decision-makers? Case studies of Mexican policies.

Though the problems translating or applying research in policy-making are legion, solutions are rare. As developing countries increase their capacities to develop effective local solutions to their health problems, they confront the research/policy dilemma. Yet few descriptive studies of research-policy links can be found from developing countries, and the relevance of European and North American models and data is questionable. We report the results of a descriptive study from Mexico of the relationship between health research and policy in four vertical programmes (AIDS, cholera, family planning, immunization). We interviewed 67 researchers and policy-makers from different institutions and levels of responsibility. We analyzed interviewee responses looking for factors that promoted or impeded exchanges between researchers and policy-makers. These were, in turn, divided into emphases on content, actors, process, and context. Many of the promoting factors resembled findings from studies in industrialized countries. Some important differences across the four programmes, which also distinguish them from industrialized country programmes, included extent of reliance on formal communication channels, role of the mass media in building social consensus or creating discord, levels of social consensus, role of foreign donors, and extent of support for biomedical versus social research. We recommend various ways to increase the impact of research on health policy-making in Mexico. Some of the largest challenges include the fact that researchers are but one of many interest groups, and research but one input among many equally legitimate elements to be considered by policy-makers. Another important challenge in Mexico is the relatively small role played by the public in policy-making. Further democratic changes in Mexico may be the most important incentive to increase the use of research in policy-making.

Acquired Immunodeficiency Syndrome↗
PubMed1999

Fibrinolytic and antithrombotic regimens in recently completed, ongoing and planned clinical trials in myocardial infarction.

Myocardial infarction carries significant short-term and long-term risks of morbidity and mortality. Traditional treatment for acute myocardial infarction has significantly improved the outcomes of patients suffering from this condition. Recent clinical trials have focused on the use of novel fibrinolytics, glycoprotein IIb/IIIa receptor antagonists, low-molecular-weight heparin, direct thrombin inhibitors and myocardial protection, in an attempt to improve the prognosis of these patients. This clinical trials report reviews the rationale and design of recently completed, ongoing and planned major Phase II and III clinical trials on fibrinolytic and antithrombotic regimens for the treatment of myocardial infarction.

Journal Article↗
PubMed1999

Higher rates of coronary angiography and revascularization following myocardial infarction may be associated with greater survival in the United States than in Canada. The CARS Investigators (Coumadin/Aspirin Reinfarction Study).

BACKGROUND: Significant differences are known to exist between the United States and Canada with respect to coronary catheterization and intervention. In a post hoc analysis, it was hypothesized that these differences may have the greatest impact on outcome in patients at risk for recurrent events such as those following myocardial infarction (MI). PATIENTS AND METHODS: The hypothesis was tested in a nonrandomized comparison of the catheterization and revascularization patterns for patients following acute MI in 7029 patients in the United States and 1774 patients in Canada who participated in the Coumadin/Aspirin Reinfarction Study (CARS). CARS tested the effectiveness of low dose warfarin in combination with acetylsalicylic acid (ASA) versus ASA alone in reducing cardiovascular morbidity and mortality. RESULTS: Before study enrollment (median day 7 to 8), 84.5% of the American patients underwent coronary angiography compared with only 7.7% in Canada (P<0.01). CARS patients in the United States underwent significantly more frequent angioplasty during their hospital admission before study enrollment than their Canadian counterparts (55.8% versus 3.0%, respectively, P<0.01), and there was a more frequent use of intravenous heparin among American CARS patients (96% versus 88%, respectively, P<0.01) but less frequent administration of thrombolytic therapy (44% versus 49%, respectively, P<0.01). For follow-up of up to 32 months, American CARS patients had significantly fewer primary events (cardiovascular deaths, nonfatal MI, nonfatal ischemic stroke) than Canadian patients. Cumulative estimate of a primary end point comparing American with Canadian patients was, respectively, 2.0% versus 3.1% at one month, 8.0% versus 11.3% at one year and 11.6% versus 15.0% at two years. Thus, time to the primary event was significantly longer in American patients (P=0.0001). All-cause mortality estimates at 12 months were 2.2% and 4.0%, respectively, for the American and Canadian CARS subgroups. When management for the index MI (ie, angiography and angioplasty) is included in the model, the risk of death for Canadian versus American subgroups of CARS is not statistically different (0.9, 95% CI 0.6 to 1.2, P=0.40). CONCLUSION: Among study participants, American patients experienced a better outcome than Canadian patients, which may be attributable to more aggressive management based on early coronary angiography and angioplasty. However, angioplasty before study enrollment in American patients may have resulted in enrollment of lower risk patients. This selection bias limits the scope of the comparison.

Aged↗
PubMed1998

Low-molecular-weight heparins in non-ST-segment elevation ischemia: the ESSENCE trial. Efficacy and Safety of Subcutaneous Enoxaparin versus intravenous unfractionated heparin, in non-Q-wave Coronary Events.

Combination antithrombotic therapy with heparin plus aspirin decreases the risk of recurrent ischemic events in patients with acute coronary syndromes without persistent ST-segment elevation. Compared with standard unfractionated heparin, low-molecular-weight heparin (LMWH) has a more predictable antithrombotic effect, is easier to administer, and does not require coagulation monitoring. At 176 hospitals in 3 continents, 3,171 patients with rest unstable angina or non-wave myocardial infarction were randomly assigned to either enoxaparin (a LMWH), 1 mg/kg twice daily subcutaneously, or to continuous intravenous unfractionated heparin, for a minimum of 48 hours to a maximum of 8 days. Trial medication was administered in a double-blind, placebo-controlled fashion. At 14 days, the primary endpoint, the composite risk of death, myocardial infarction, or recurrent angina with electrocardiographic changes or prompting intervention, was significantly lower in patients assigned to enoxaparin compared with heparin (16.6% vs 19.8%; odds ratio [OR] 1.24; 95% confidence interval [CI] 1.04-1.49; p = 0.019). At 30 days, the composite risk of death, myocardial infarction, or recurrent angina remained significantly lower in the enoxaparin group compared with the unfractionated heparin group (19.8% vs 23.3%, OR 1.23; 95% CI 1.0-1.46, p = 0.016). The rate of revascularization procedures at 30 days was also significantly lower in patients assigned to enoxaparin (27.1% vs 32.2%, p = 0.001). The 30-day incidence of major bleeding complication was 6.5% versus 7.0% (p = not significant), but the incidence of minor bleeding was significantly higher in the enoxaparin group (13.8% vs 8.8%, p <0.001) due primarily to injection-site ecchymosis. Thus, combination antithrombotic therapy with enoxaparin plus aspirin is more effective than unfractionated heparin plus aspirin in decreasing ischemic outcomes in patients with unstable angina or non-Q-wave myocardial infarction in the early (30 days) phase. The lower recurrent ischemic event rate seen with the LMWH, enoxaparin, is achieved without an increase in major bleeding, but with an increase in minor bleeding complications due mainly to injection-site ecchymosis.

Adolescent↗
PubMed1998

Prognostic significance of ST segment shift early after resolution of ST elevation in patients with myocardial infarction treated with thrombolytic therapy: the GUSTO-I ST Segment Monitoring Substudy.

OBJECTIVES: We sought to study the relation between recurrent ST segment shift within 6 to 24 h of initial resolution of ST elevation after thrombolytic therapy and 30-day and 1-year mortality. BACKGROUND: Rapid and stable resolution of ST segment elevation in relation to thrombolytic therapy in patients with an acute myocardial infarction is an indicator of culprit artery patency. Whether recurrence of ST segment shift during continuous ST monitoring after initial resolution is related to poor prognosis has not been studied. METHODS: ST segment monitoring was performed within 30 min after thrombolytic therapy for acute myocardial infarction. The predictive value of a new ST segment shift (assessed as > or = 0.1-mV deviation from the baseline) 6 to 24 h after thrombolytic therapy was studied with respect to 30-day and 1-year mortality. RESULTS: Of 734 patients, 243 had a new ST segment shift (33%). The 30-day mortality rate in patients with an ST shift (7.8%) was significantly higher than that in patients without an ST shift (2.25%, p = 0.001), as was the 1-year mortality rate (10.3% vs. 5.7%, respectively, p = 0.025). Multivariable analysis revealed an independent predictive value of ST shift with respect to 30-day mortality (p = 0.008), even after consideration of multiple clinical risk factors in the overall Global Utilization of Streptokinase and TPA for Occluded Coronary Arteries (GUSTO)-I mortality model (p = 0.0001). Moreover, the duration of the ST shift bore a direct relation with 1-year mortality (p = 0.008). CONCLUSIONS: Detection of ST segment shift early after thrombolytic therapy for acute myocardial infarction is a simple, noninvasive means of identifying patients at high risk and is superior to other commonly assessed clinical risk factors. Thus, patients with a new ST shift after the first 6 h, but within 24 h, represent a high risk group that may benefit from more aggressive intervention, whereas patients without evidence of an ST shift represent a low risk subgroup.

Electrocardiography↗
PubMed1998

Non-Q-wave versus Q-wave myocardial infarction after thrombolytic therapy: angiographic and prognostic insights from the global utilization of streptokinase and tissue plasminogen activator for occluded coronary arteries-I angiographic substudy. GUSTO-I Angiographic Investigators.

BACKGROUND: Although the stratification of patients with myocardial infarction into ECG subsets based on the presence or absence of new Q waves has important clinical and prognostic utility, systematic evaluation of the impact of thrombolytic therapy on the subsequent development and prognosis of non-Q-wave infarction has been limited to date. METHODS AND RESULTS: We examined 12-lead ECG, coronary anatomy, left ventricular function, and mortality among 2046 patients with ST-segment elevation infarction from the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries angiographic subset to gain further insight into the pathophysiology and prognosis of Q- versus non-Q-wave infarction in the thrombolytic era. Non-Q-wave infarction developed in 409 patients (20%) after thrombolytic therapy. Compared with Q-wave patients, non-Q-wave patients were more likely to present with lesser ST-segment elevation in a nonanterior location. The infarct-related artery in non-Q-wave patients was more likely to be nonanterior (67% versus 58%, P=.012) and distally located (33% versus 39%, P=.021). Early (90-minute, 77% versus 65%, P=.001) and complete (54% versus 44%, P<.001) infarct-related artery patency was greater among the non-Q-wave group. Non-Q-wave patients had better global (ejection fraction, 66% versus 57%; P<.0001) and regional left ventricular function (10 versus 24 abnormal chords, P=.0001). In-hospital, 30-day, 1-year, and 2-year (6.3% versus 10.1%, P=.02) mortality rates were lower among non-Q-wave patients. CONCLUSIONS: The excellent prognosis among the subgroup of patients who develop non-Q-wave infarction after thrombolysis is related to early, complete, and sustained infarct-related artery patency with resultant limitation of left ventricular infarction and dysfunction.

Aged↗
PubMed1998

Prognostic implications of hyperglycaemia in paediatric head injury.

Fifty children with head injury were evaluated in an attempt to establish a correlation between post-traumatic hyperglycaemia and long-term outcome. In all the patients, the blood glucose level was measured on admission and on the days following the trauma (threshold of normal value set at 150 mg/dl). Hyperglycaemia was seen more frequently in children with severe head injury than in those with mild and moderate head injury. It was present in 87.5% of the patients with a Glasgow Coma Score (GCS) < or =8 (the average blood glucose level on admission was 237.8+/-92 mg/dl), in 60% of the patients with a GCS of 9-12 (178+/-78.7 mg/dl) and only in 25% of those with a GCS of 13-15 (131.5+/-39 mg/dl). A close correlation was also seen between the outcome and the blood glucose level. In fact, the blood glucose on admission was higher in the patients with a poor outcome, i.e. in those having a Glasgow Outcome Score (GOS) of 2 or 3 and in those who died (GOS 1), than in the patients with a good outcome (GOS of 4 or 5). Finally, hyperglycaemia persisted beyond the first 24 h after trauma in all the children who died or who survived with a poor outcome. Hyperglycaemia, and especially its persistence over time, appears to be an important negative prognostic factor in children with head injury.

Adolescent↗
PubMed1998

"Alone, I wouldn't have known what to do": a qualitative study on social support during labor and delivery in Mexico.

This article presents some of the most relevant qualitative results of a trial to evaluate the effects of the provision of psychosocial support to first-time mothers during labor, childbirth and in the immediate postpartum period in a social security hospital in Mexico City. The article focuses on the experiences of mothers who have received psychosocial support from a doula (the term doula is used to identify a woman who provides continuous support to a woman during labor. delivery and the immediate postpartum period) and compares them with the experiences of those women who gave birth following normal hospital routine. Sixteen in-depth interviews were held with women in the immediate post partum period (eight of whom had been accompanied by a doula and eight who had not) before they were discharged from hospital, and the results were analyzed using qualitative techniques. The interviews showed that the women accompanied by a doula had a more positive childbirth experience. The differences between both groups related to their perceptions of the childbirth experience; the treatment they received from hospital staff; the information they were given and how well they understood it; their perception of hospital routines; their feelings about cesarean sections and, spatial and temporal perceptions. The most important difference between the two groups was the way they expressed their feelings about their own labor, their sense of control and their self-perception.

Delivery, Obstetric↗
PubMed1998

Conceptual bases and methodology for the evaluation of women's and providers' perception of the quality of antenatal care in the WHO Antenatal Care Randomised Controlled Trial.

In this paper, we describe the conceptual bases and methodology used to assess women's and providers' perception of the quality of antenatal care, as part of a large randomised trial in four developing countries. Information has been obtained by applying both qualitative and quantitative methodologies. The focus group discussions and in-depth interviews have contributed useful insights into the cultural milieu in which care is provided, users' and providers' expectations, and their concept of quality. Based on these findings, we developed two standardised questionnaires, one being administered to a representative sample of pregnant women (n = 1600) and the other for all care providers. In this paper we present some of the findings of the focus group discussions and in-depth interviews with women in one country as an example of the kind of information we have obtained. Women expressed their point of view concerning a reduced number of visits, type of provider, information that they get during clinical encounters and interpersonal relations with health professionals. The qualitative information, together with the data we obtain from the surveys, will highlight the aspects that will have be to considered if the new model of care is to be introduced on a routine basis.

Argentina↗
PubMed1998

Effects of psychosocial support during labour and childbirth on breastfeeding, medical interventions, and mothers' wellbeing in a Mexican public hospital: a randomised clinical trial.

OBJECT: To evaluate the effects of psychosocial support during labour, delivery and the immediate postpartum period provided by a female companion (doula). DESIGN: The effects of the intervention were assessed by means of a randomised clinical trial. Social support by a doula was provided to women in the intervention group, while women in the control arm received routine care. SETTING: A large social security hospital in Mexico City. PARTICIPANTS: Seven hundred and twenty-four women with a single fetus, no previous vaginal delivery, < 6 cm of cervical dilatation, and no indications for an elective caesarean section were randomly assigned to be accompanied by a doula, or to receive routine care. OUTCOME MEASURES: Breastfeeding practices, duration of labour, medical interventions, mother's emotional conditions, and newborn's health. METHODS: Blinded interviewers obtained data from the clinical records, during encounters with women in the immediate postpartum period, and at their homes 40 days after birth. Relative risks and confidence intervals were estimated for all relevant outcomes. RESULTS: The frequency of exclusive breastfeeding one month after birth was significantly higher in the intervention group (RR 1.64; I-C: 1.01-2.64), as were the behaviours that promote breastfeeding. However, the programme did not achieve a significant effect on full breastfeeding. More women in the intervention group perceived a high degree of control over the delivery experience, and the duration of labour was shorter than in the control group (4.56 hours vs 5.58 hours; RR 1.07 CI (95%) = 1.52 to -0.51). There were no effects either on medical interventions, mothers' anxiety, self-esteem, perception of pain and satisfaction, or in newborns' conditions. CONCLUSIONS: Psychosocial support by doulas had a positive effect on breastfeeding and duration of labour. It had a more limited impact on medical interventions, perhaps because of the strict routine in hospital procedures, the cultural background of the women, the short duration of the intervention, and the profile of the doulas. It is important to include psychosocial support as a component of breastfeeding promotion strategies.

Anxiety↗
PubMed1997

A comparison of low-molecular-weight heparin with unfractionated heparin for unstable coronary artery disease. Efficacy and Safety of Subcutaneous Enoxaparin in Non-Q-Wave Coronary Events Study Group.

BACKGROUND: Antithrombotic therapy with heparin plus aspirin reduces the rate of ischemic events in patients with unstable coronary artery disease. Low-molecular-weight heparin has a more predictable anticoagulant effect than standard unfractionated heparin, is easier to administer, and does not require monitoring. METHODS: In a double-blind, placebo-controlled study, we randomly assigned 3171 patients with angina at rest or non-Q-wave myocardial infarction to receive either 1 mg of enoxaparin (low-molecular-weight heparin) per kilogram of body weight, administered subcutaneously twice daily, or continuous intravenous unfractionated heparin. Therapy was continued for a minimum of 48 hours to a maximum of 8 days, and we collected data on important coronary end points over a period of 30 days. RESULTS: At 14 days the risk of death, myocardial infarction, or recurrent angina was significantly lower in the patients assigned to enoxaparin than in those assigned to unfractionated heparin (16.6 percent vs. 19.8 percent, P=0.019). At 30 days, the risk of this composite end point remained significantly lower in the enoxaparin group (19.8 percent vs. 23.3 percent, P=0.016). The need for revascularization procedures at 30 days was also significantly less frequent in the patients assigned to enoxaparin (27.1 percent vs. 32.2 percent, P=0.001). The 30-day incidence of major bleeding complications was 6.5 percent in the enoxaparin group and 7.0 percent in the unfractionated-heparin group, but the incidence of bleeding overall was significantly higher in the enoxaparin group (18.4 percent vs. 14.2 percent, P=0.001), primarily because of ecchymoses at injection sites. CONCLUSIONS: Antithrombotic therapy with enoxaparin plus aspirin was more effective than unfractionated heparin plus aspirin in reducing the incidence of ischemic events in patients with unstable angina or non-Q-wave myocardial infarction in the early phase. This benefit of enoxaparin was achieved with an increase in minor but not in major bleeding.

Aged↗