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Biomedical subjects

A Levin

Publications and source records attributed to A Levin.

At least 55 records · Page 3Linked to original sources
PubMed1999

A fully automated multicapillary electrophoresis device for DNA analysis.

We describe the construction and performance of a fully automated multicapillary electrophoresis system for the analysis of fluorescently labeled biomolecules. A special detection system allows the simultaneous spectral analysis of all 96 capillaries. The main features are true parallel detection without any moving parts, high robustness, and full compatibility to existing protocols. The device can process up to 40 microtiter plates (96 and 384 well) without human interference, which means up to 15,000 samples before it has to be reloaded.

Automation↗
PubMed1999

Left ventricular mass index increase in early renal disease: impact of decline in hemoglobin.

Cardiovascular disease occurs in patients with progressive renal disease both before and after the initiation of dialysis. Left ventricular hypertrophy (LVH) is an independent predictor of morbidity and mortality in dialysis populations and is common in the renal insufficiency population. LVH is associated with numerous modifiable risk factors, but little is known about LV growth (LVG) in mild-to-moderate renal insufficiency. This prospective multicenter Canadian cohort study identifies factors associated with LVG, measured using two-dimensional-targeted M-mode echocardiography. Eight centers enrolled 446 patients, 318 of whom had protocol-mandated clinical, laboratory, and echocardiographic measurements recorded. We report 246 patients with assessable echocardiograms at both baseline and 12 months with an overall prevalence of LVH of 36%. LV mass index (LVMI) increased significantly (>20% of baseline or >20 g/m2) from baseline to 12 months in 25% of the population. Other than baseline LVMI, no differences in baseline variables were noted between patients with and without LVG. However, there were significant differences in decline of Hgb level (-0.854 v -0.108 g/dL; P = 0.0001) and change in systolic blood pressure (+6.50 v -1.09 mm Hg; P = 0.03) between the groups with and without LVG. Multivariate analysis showed the independent contribution of decrease in Hgb level (odds ratio [OR], 1.32 for each 0.5-g/dL decrease; P = 0.004), increase in systolic blood pressure (OR, 1.11 for each 5-mm Hg increase; P = 0.01), and lower baseline LVMI (OR, 0.85 for each 10-g/m2; P = 0.011) in predicting LVG. Thus, after adjusting for baseline LVMI, Hgb level and systolic blood pressure remain independently important predictors of LVG. We defined the important modifiable risk factors. There remains a critical need to establish optimal therapeutic strategies and targets to improve clinical outcomes.

Anemia↗
PubMed1999

Steroid-responsive pleuropericarditis and livedo reticularis in an unusual case of adult-onset primary hyperoxaluria.

We present a case of a 54-year-old woman with rapidly progressive renal failure of uncertain origin, who developed pleuropericarditis and livedo reticularis 6 weeks after initiation of hemodialysis (HD). The presentation with acute renal failure, the development of serositis, and the dramatic clinical response to empiric steroid therapy initially suggested the diagnosis of a systemic inflammatory disorder or vasculitis. Renal biopsy, performed 3 days after presentation, suggested crystal deposition disease, and subsequent investigations, using both dialysate oxalate concentrations and liver biopsy, led to the diagnosis of primary hyperoxaluria (PH). We discuss this atypical adult presentation of PH and propose a role for the use of steroids in the management of the acute inflammatory symptoms of oxalosis. We also briefly discuss the current medical management of patients with PH, including transplantation.

Age of Onset↗
PubMed1999

Effect of price and access on contraceptive use.

The Family Planning Program in Bangladesh has been very successful. The contraceptive prevalence rate (CPR) has increased from 13% in 1979 to 49% in 1996. Now that the program has matured and demand for family planning has been created, the Ministry of Health and Family Welfare (MOHFW) of the Government of Bangladesh is concerned with increasing its financial sustainability. Options to increase financial sustainability include cost sharing and a gradual transition from doorstep to static clinic delivery of contraceptives. Many of these alternatives would involve additional travel time or charges for consumers, and it is important to estimate the effect that these additional prices would have on the use of contraception. The effect of economic constraints, such as cash price and access to services on contraceptive method use, the choice of contraceptive method and provider choice, has been analyzed, taking into account the socioeconomic factors that influence decision-making for individual family members. Two data sources have been used for this analysis: (1) a survey on use of contraception and (2) two baseline surveys of 1993 and 1994 in the two field sites of the MCH-FP Extension Project (Rural) of International Center for Diarrhoeal Disease Research, Bangladesh. No effect of cash prices was found on the probability of use of any contraceptive method, but clients were to a limited extent responsive to price in making choices about contraceptive methods and providers. In addition, couples were less likely to use contraception or choose methods if the travel time to fixed clinics was greater than 30 min.

Adult↗
PubMed1999

Management of membranoproliferative glomerulonephritis: evidence-based recommendations.

Idiopathic membranoproliferative glomerulonephritis (MPGN) is one of the least common types of GN. This article critically evaluates the literature and generates evidence-based recommendations for the management of idiopathic MPGN. For all age groups, for idiopathic MPGN with normal renal function and asymptomatic nonnephrotic range proteinuria, no specific therapy is necessary (grades B and C). Close follow-up every three to four months, with specific attention to renal function, proteinuria, and blood pressure control, is recommended. In children with MPGN and nephrotic syndrome and/or impaired renal function, a trial of steroids is warranted (grade A). The best data suggest high-dose, alternate-day steroids for a period of 6 to 12 months (40 mg/m2 on alternate days). If no benefit is seen, discontinuation with close follow-up and attention to conservative treatment (that is, blood pressure control, use of agents to reduce proteinuria, and correction of metabolic abnormalities) is recommended. In adults with MPGN, impaired renal function, and/or nephrotic-range proteinuria, a trial of aspirin (325 mg daily), dipyridamole (75 to 100 mg tid), or a combination of the two for 12 months is reasonable (grade B). Again, if no benefits are seen, the treatment should be stopped. Attention to factors known to delay the progression of renal decline and close follow-up should be part of the treatment plan (grades B and C).

Adult↗
PubMed1999

Humane Neonatal Care Initiative.

The author has worked for many years in experimental departments in the former Soviet health system. Now, with integration into the western health system, many questions are being asked about high-technology neonatal medicine and whether it is sufficiently humane. The Baby Friendly Hospital Initiative (BFHI) movement is well known all over the world, but unfortunately it is only used for healthy children in maternity hospitals. A paradoxical situation has been created: the routines of maternity wards comply with the BFHI, whereas a neonatal intensive care unit in the same hospital may not meet the requirements of the BFHI. BFHI mainly cover breastfeeding in maternity hospitals. Humane Neonatal Care Initiatives include minimum aggressive therapy, minimum contact between sick newborns and medical staff, and maximum contact with mothers; the number of tests and examinations should be reduced to a minimum. Eleven steps towards the improvement of psychosocial and medical care in units for sick newborns are presented. This article is intended to provoke serious discussion.

Breast Feeding↗
PubMed1999

Risk factors for human T cell lymphotropic virus type II infection among the Guaymi Indians of Panama.

To examine risk factors for human T cell lymphotropic virus type II (HTLV-II) infection, a case-control study was conducted among the Guaymi Indians of Panama. In females, HTLV-II seropositivity was associated with early sexual intercourse (</=13 vs. >15 years; odds ratio [OR], 2.50; 95% confidence interval [CI], 1.11-6.14) and number of lifetime sex partners. One partner increased risk of seropositivity by 30% (OR, 1.30; CI, 1.05-1.64), and risk increased with number of partners. Similar risk was associated with number of long-term sexual relationships. Among males, intercourse with prostitutes was associated with HTLV-II seropositivity (OR, 1.68; CI, 1.04-2.72). These data support a role for sexual transmission in HTLV-II infection. Association of seropositivity with primary residence in a traditional village (OR, 3.75; CI, 1.02-15.38) and lack of formal education (0 vs. >6 years [OR, 3.89; CI, 1.67-9.82]) observed in males may reflect differences in sexual practices associated with acculturation.

Adolescent↗
PubMed1999

Anaemia in the patient with renal insufficiency: documenting the impact and reviewing treatment strategies.

This paper attempts to present a context in which nephrologists can re-evaluate definitions of acceptable haemoglobin levels in renal populations, and re-examine previous notions about the impact of relative and absolute anaemia on patients with progressive renal insufficiency. Also, the nephrology community needs to examine rigorously treatment strategies aimed at reversing anaemia specifically in this population. Data are presented to support the notion that anaemia is disadvantageous to the patients with progressive renal insufficiency, and does need to be treated. The ongoing poor prognosis of patients receiving renal replacement therapy may well be due to our previous inattention to this correctable cause of morbidity early in the course of progressive renal disease. Long-term studies addressing these important clinical issues need to be supported, and evaluated within both immediate and future economic implications.

Anemia↗
PubMed1999

Homocyst(e)ine and vascular access complications in haemodialysis patients: insights into a complex metabolic relationship.

BACKGROUND: As elevated total homocyst(e)ine (tHcy) is associated with increased risk of vascular thrombosis, we hypothesized that the elevated levels of tHcy seen in patients on haemodialysis may be associated with an increased risk of thrombosis of native arteriovenous fistulae (vascular access failure). Our study was designed to investigate the relationship between tHcy and vascular access failure. The relationship between tHcy and mortality was explored as a secondary analysis. METHODS: The study comprised a cross-sectional analysis of 96 haemodialysis patients at a single university-affiliated hospital and a subsequent 9-month prospective follow-up of 88 of the 96 patients. RESULTS: Levels of tHcy (median 30 micromol/l) were elevated. In the initial cross-sectional sample, there was an inverse relationship between tHcy and history of vascular access failure which was not observed in the prospective study. Variables influencing the risk of vascular access failure in the prospective study included history of previous vascular access failure (RR=2.93, P=0.03), use of antiplatelet agents (RR=0.13, P=0.01), increased urea reduction ratio (RR=0.55 for a 5% increase, P=0.01) and increased weight (RR=0.61 for a 10 kg increase, P=0.02). Secondary analysis showed an unexpected inverse relationship between tHcy and mortality (RR=0.033 for 1 log increase in tHcy, P=0.006), such that the lower levels of tHcy were associated with an increased risk of death in short-term follow-up. CONCLUSION: We did not demonstrate a relationship between tHcy and risk of vascular access failure. Patients with the lowest levels of tHcy appeared to be at increased risk of death in this short-term follow-up. The relationship of tHcy to vascular access complications and death in haemodialysis patients appears complex and requires further study.

Adult↗
PubMed1999

How should anaemia be managed in pre-dialysis patients?

Anaemia is a common problem in patients with renal failure, whether or not they are on dialysis. There is a continuum of declining renal function. In addition, the creatinine clearance at which dialysis is initiated varies widely between institutions and between studies. The term 'progressive renal insufficiency' is therefore preferable to 'pre-dialysis'. The adverse effects of renal anaemia on left ventricular mass become apparent early in the course of progressive renal insufficiency; 75% of patients starting dialysis already have left ventricular hypertrophy (LVH). Correction of anaemia in patients with progressive renal insufficiency has been shown to improve physical function and anaemia-related symptoms, but no controlled studies have yet been conducted to determine its effects on LVH. Although one animal study generated some concern that epoetin may exacerbate a decline in renal function, there is no evidence from human studies for any such effect. Treatment of anaemia with epoetin in anaemic patients with progressive renal insufficiency is therefore recommended, provided blood pressure is controlled. To date, however, there are insufficient data to determine whether normalization of haemoglobin is advisable in this patient group. Detection and correction of iron deficiency is important to achieve the full benefits of epoetin, though recommendations cannot yet be made regarding the optimum route and timing of iron supplementation in patients with progressive renal insufficiency. In these patients the role of other adjuvant therapies, such as L-carnitine, vitamin B6, vitamin B12 and folic acid, also requires further investigation.

Anemia↗
PubMed1998

Partial tetrasomy with triplication of chromosome (5) (p14-p15.33) in a patient with severe multiple congenital anomalies.

We report on a newborn infant with a de novo triplication of the distal segment of 5p: 46,XX,trp(5) (pter-->p14::p14-->p15.33::p15.33--> qter) and multiple congenital anomalies consistent with triplication of 5p. Partial triplication was documented by fluorescence in situ hybridization with a cosmid probe specific for 5p15.2 and microdissected probes obtained from "5pter." Partial duplication of the short arm of chromosome 5 is associated with a specific phenotype that appears to be dependent on the chromosomal region duplicated. Duplication of 5p with breakpoints proximal to band p14 is generally associated with distinct craniofacial malformations, cardiac, renal, intestinal, and limb defects, and mental retardation, whereas duplications with breakpoints distal to 5p14 result in a milder phenotype characterized by minor facial anomalies, developmental delay, and seizures. The most proximal breakpoints of the partial triplication in this patient was estimated to be 5p14, suggesting that a more severe phenotype can occur with triplication of the more distal segment.

Abnormalities, Multiple↗