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J Levin

Publications and source records attributed to J Levin.

At least 55 records · Page 3Linked to original sources

A trial of L-deprenyl for the treatment of neuroleptic-induced parkinsonism.

This study examined the potential of L-Deprenyl, a selective monoamine oxidase-B (MAO-B) inhibitor, for the treatment of neuroleptic-induced parkinsonism (NIP). Thirty-one consecutive schizophrenic or schizophreniform patients were treated with haloperidol in a flexible dose design. Nineteen of them developed NIP and were administered adjunctive L-Deprenyl 10 mg/d for six weeks in an open fixed-dose design. One patient had to be withdrawn from the study because of exacerbation of the NIP. Severity of NIP was mild to moderate throughout the whole study period in all other cases. Five patients were considered to require biperiden 2-4 mg/d in addition to L-Deprenyl after two weeks of treatment, although they did not differ from the other 13 patients in any of the variables studied. A significant improvement in NIP was found in both groups of patients, with no psychotic exacerbation or a change in the dosage of haloperidol. These findings suggest that selective MAO-B inhibitors may be effective in some patients with mild to moderate NIP.

Adult↗

Mass mailing and staff experience in a total recruitment program for a clinical trial: the SHEP experience. Systolic Hypertension in the Elderly Program. Cooperative Research Group.

The Systolic Hypertension in the Elderly Program (SHEP) staff contacted 447,921 screenees, of whom 11,919 (2.7%) were originally eligible and 4,736 (1.1%) maintained eligibility and were randomized. The total number of participants enrolled at the 16 clinical centers ranged from 133 to 559. The low yield of screenees to randomizations resulted from the study design, not from low levels of agreement to participate, and required the employment of a variety of recruitment strategies in a prudent overall plan. SHEP was one of the first clinical trials to use mass mailing as a primary strategy of recruitment. The study used mailing lists from seven generic sources. More than 3.4 million letters of invitation were mailed; they yielded an overall response rate of 4.3%. Motor vehicle and voter registration lists provided the greatest numbers of names. Mailings to members of health maintenance organizations (HMOs) and registrants of the Health Care Finance Administration (HCFA) provided the greatest response rates. Considerable variability in response rates existed among clinical centers using generically similar mailing lists. Generally, the number of hours spent on recruitment showed a positive, but not statistically significant, association with randomization yields. The recruitment yield was statistically significantly higher in clinics with experienced recruitment coordinators than in clinics with inexperienced ones (p = 0.0008). From these findings we conclude that mass mailing is an important strategy in an overall recruitment program, that the involvement of experienced recruitment staff is important, and that although the total time spent by staff on recruitment may also improve results, it matters less than the staff's level of recruiting experience.

Aged↗

Effect of arsenic trioxide on viability, proliferation, and apoptosis in human megakaryocytic leukemia cell lines.

Arsenic trioxide (As2O3) has been demonstrated to be effective for the treatment of acute promyelocytic leukemia (APL) and to inhibit proliferation and produce apoptosis in the APL cell line NB4. To determine if As2O3 might be useful for the treatment of other lineages, we investigated the effects of As2O3 on viability, proliferation, and induction of apoptosis in the megakaryocytic leukemia cell lines HEL, Meg-01, UT7, and M07e. Our results showed that As2O3, at concentrations of 0.1-2.0 microM, causes a dose- and time-dependent inhibition of survival and growth in all four megakaryocytic leukemia cell lines studied. In contrast, As2O3 at similar concentrations had no effects on either viability or growth of the nonmegakaryocytic leukemia cell line HL60 and two human breast cancer cell lines, ZR75 and MCF7. In situ end-labeling of DNA fragments (TUNEL assay) indicated that As2O3, at concentrations of 0.5-2 microM, could significantly induce apoptosis in the aforementioned four megakaryocytic leukemia cell lines, but not in the nonmegakaryocytic HL60, ZR75, and MCF7 cell lines. These results were confirmed using conventional morphologic assessment and the DNA ladder assay. Induction of apoptosis in arsenic-treated Meg-01 and UT7 cells was accompanied by a dose-response decrease of Bcl-2 protein, whereas As2O3 had no effect on this measurement in HL60, ZR75, and MCF7 cell lines. Pertinently, these concentrations of As2O3 produced identical changes in the characteristics of the APL cell line NB4. Collectively, these data demonstrate that As2O3 can selectively inhibit growth and induce apoptosis in megakaryocytic leukemia cell lines. The use of As2O3 for the treatment of malignant megakaryocytic disorders should be considered.

Apoptosis↗

Safety and efficacy of shed mediastinal blood transfusion after cardiac surgery: a multicenter observational study. Multicenter Study of Perioperative Ischemia Research Group.

OBJECTIVE: To examine the efficacy and safety of shed mediastinal blood (SMB) transfusion in preventing allogenic red blood cell (RBC) transfusion. DESIGN: An observational clinical study. SETTING: Twelve US academic medical centers. PARTICIPANTS: Six hundred seventeen patients undergoing elective primary coronary artery bypass grafting. INTERVENTIONS: Patients were administered SMB transfusion or not, according to institutional and individual practice, without random assignment. MEASUREMENTS AND RESULTS: The independent effect of SMB transfusion on postoperative RBC transfusion was examined by multivariable modeling. Potential complications of SMB transfusion, such as bleeding and infection, were examined. Three hundred twelve of the study patients (51%) received postoperative SMB transfusion (mean volume, 554 +/- 359 mL). Patients transfused with SMB had significantly lower volumes of RBC transfusion than those not receiving SMB (0.86 +/- 1.50 v 1.08 +/- 1.65 units; p < 0.05). However, multivariable analysis showed that SMB transfusion was not predictive of postoperative RBC transfusion. Demographic factors (older age, female sex), institution, and postoperative events (greater chest tube drainage, lower hemoglobin level on arrival to the intensive care unit, and use of inotropes) were significant predictors of RBC transfusion. The volume of chest tube drainage on the operative day (707 +/- 392 v 673 +/- 460 mL; p = 0.30), reoperation for hemorrhage (3.1% v2.5%; p = 0.68), and overall frequency of infection (5.8% v 6.6%; p = 0.81) were similar between patients receiving and not receiving SMB, respectively. However, in patients who did not receive allogenic RBC transfusion, there was a significantly greater frequency of wound infection in the SMB group (3.6% v0%; p = 0.02). CONCLUSION: These data suggest that SMB is ineffective as a blood conservation method and may be associated with a greater frequency of wound infection.

Aged↗

Biological simulations in drug discovery.

Simulation of biological processes, systems and organs is a necessary complement to genetic and molecular sequencing. Using the heart as an example, the authors describe the way in which such modelling can be used in drug discovery, development and assessment. The technology is readily applicable to other organs and systems as well; models of neurones and neuronal systems, the pancreas and the lungs have already been developed. Ultimately, a virtual corpus is feasible. Genes can only specify the properties of the proteins they code for, and any integrative properties of the system must be 'computed' by their interactions-Sydney Brenner

Journal Article↗

Fibrinogen-coated albumin microcapsules reduce bleeding in severely thrombocytopenic rabbits.

Severe thrombocytopenia frequently occurs in patients receiving chemotherapy and in patients with autoimmune disorders. Thrombocytopenia is associated with bleeding, which may be serious and life threatening. Current treatment strategies for thrombocytopenia may require transfusion of allogeneic platelets, which is associated with serious drawbacks. These include the occurrence of anti-platelet antibodies, which may result in refractoriness to further platelet transfusions, and the potential risk of transfer of blood-borne diseases. Therefore, we have recently developed a platelet substitute product (Synthocytes), which is composed of human albumin microcapsules with fibrinogen immobilized on their surface. Here we show that the intravenous administration of these microcapsules not only corrects the prolonged bleeding time in rabbits rendered thrombocytopenic either by anti-platelet antibodies or by chemotherapy, but also reduces bleeding from surgical wounds inflicted in the abdominal skin and musculature. No potential systemic prothrombotic effect of the microcapsules was observed in a model of rabbit venous thrombosis. As for the mechanism of action, experiments with normal and thrombocytopenic human blood in an endothelial cell matrix-coated perfusion chamber demonstrated an interaction between the fibrinogen-coated albumin microcapsules and native platelets. It was shown that the fibrinogen-coated albumin microcapsules could facilitate platelet adhesion to endothelial cell matrix and correct the impaired formation of platelet aggregates in relatively platelet-poor blood. This study indicates that fibrinogen-coated albumin microcapsules can act to improve primary hemostasis under thrombocytopenic conditions and may eventually be a promising agent for prophylaxis and treatment of bleeding in patients with severe thrombocytopenia.

Albumins↗

Hemoglobin infusion augments the tumor necrosis factor response to bacterial endotoxin (lipopolysaccharide) in mice.

OBJECTIVE: To determine whether cell-free hemoglobin augments the inflammatory cascade, as detected by production of tumor necrosis factor (TNF) elicited by bacterial endotoxin (lipopolysaccharide [LPS]). DESIGN: In vivo and ex vivo study, using a mouse model of sepsis. SETTING: Animal research facility SUBJECTS: Female Swiss Webster mice. INTERVENTIONS: For the in vivo experiments, an LD50 dose (500 microg) of Escherichia coli LPS was injected intraperitoneally into mice. Cell-free crosslinked hemoglobin (60 mg/mouse) or saline was administered intravenously 10 hrs before or coincident with LPS. For the ex vivo experiments, hemoglobin (60 mg/mouse) or saline was administered intravenously to mice, and, 10 hrs later, hepatic Kupffer cells, peripheral blood mononuclear cells, or peritoneal macrophages were isolated. MEASUREMENTS AND MAIN RESULTS: Intravenous infusion of hemoglobin either 10 hrs before or coincident with intraperitoneal LPS resulted in a peak of plasma TNF that was greater than in control mice administered LPS only. Cultured Kupffer cells, isolated from mice that had received hemoglobin in vivo 10 hrs before cell collection, produced more TNF in response to LPS in vitro than cells from normal mice. A trend toward greater TNF production in vitro by peripheral blood mononuclear cells obtained from hemoglobin-treated mice also was observed. Enhanced sensitivity to LPS was not observed with cultured peritoneal macrophages from mice that had received hemoglobin. CONCLUSIONS: Intravenous hemoglobin increased the sensitivity of hepatic macrophages to subsequent stimulation by LPS. This effect may contribute to the increased mortality that we have observed in animals that have received both LPS and hemoglobin.

Animals↗

Jeff Levin, MPH, PhD. The power of love. Interview by Bonnie Horrigan.

Jeff Levin is an epidemiologist and writer living in Kansas. He was trained in religion, sociology, public health, preventive medicine, and gerontology at Duke University, the University of North Carolina, the University of Texas Medical Branch, and the University of Michigan. From 1989 to 1997 he served on the faculty of the Department of Family and Community Medicine at Eastern Virginia Medical School in Norfolk, Va. Dr Levin pioneered basic research on the epidemiology of religion. He has been funded by several National Institute of Health (NIH) grants, totaling more than $1 million in support. He has also received funding from private sources including the American Medical Association and the Institute of Noetic Sciences. Dr Levin is a senior research fellow of the National Institute for Healthcare Research; an advisory board member of the Center on Aging, Religion, and Spirituality; and past president of the International Society for the Study of Subtle Energies and Energy Medicine. He has been chair of the NIH Working Group on Quantitative Methods in Alternative Medicine, is a former member of the NIH Workgroup on Measures of Religiousness and Spirituality, and is a member of the editorial boards of several peer-reviewed scientific journals including Alternative Therapies. Dr Levin is the author of more than 110 scholarly publications, including 5 books. These include his edited book Religion in Aging and Health (Sage Publications); the newly published Essentials of Complementary and Alternative Medicine (Lippincott, Williams & Wilkins), which he edited with Dr Wayne Jonas; and the forthcoming God, Faith, and Health (John Wiley & Sons). Alternative Therapies interviewed Dr Levin at his home in Topeka, Kan, where he lives with his wife, Dr Lea Steele Levin.

Complementary Therapies↗

Unresponsive eczematous dermatitis: a case of pancreatic cancer masquerading as cutaneous T cell lymphoma.

Skin diseases may be the presenting sign of malignancy, but strict criteria are required to make the diagnosis of a paraneoplastic syndrome. Common dermatoses may also herald an underlying malignancy without meeting these criteria. We report the case of an elderly man with an unresponsive eczematous dermatitis whose evaluation eventually revealed a pancreatic carcinoma. This case is presented to alert the clinician that a common dermatosis may be the first sign of an occult malignancy, especially if it behaves in an atypical or aggressive manner or is recalcitrant to standard therapies.

Adenocarcinoma↗

Dissociative recombination of HD+ in selected vibrational quantum states

Rate coefficients for dissociative recombination of HD+ in selected vibrational states have been measured by a combination of two molecular fragment imaging methods by using the heavy-ion storage ring technique. Recombination fragment imaging yields state-to-state reaction rates. These rates are converted to rate coefficients by using vibrational level populations of the stored ion beam, derived from nuclear coordinate distributions measured on extracted ions. The results show strongly increasing rate coefficients for high vibrational excitation, where additional dissociation routes open up, in agreement with a theoretical calculation. Very low rate coefficients are found for certain, isolated vibrational states.

Journal Article↗

Transient thrombocytopenia produced by administration of macrophage colony-stimulating factor: investigations of the mechanism.

Administration of macrophage colony-stimulating factor (M-CSF) to mice (2 to 8 mg/kg/d x 5d) produced dose-dependent thrombocytopenia, which reached its nadir on days 4 to 5, followed by rapid recovery. Surprisingly, when administration of M-CSF was prolonged, the thrombocytopenia completely resolved, despite continued treatment. Splenectomy did not prevent the thrombocytopenia. Readministration of M-CSF after various intervals continued to produce the thrombocytopenic effect, even after 35 days. Measurements of Meg-CFC and megakaryocyte ploidy during the periods of M-CSF treatment and recovery of normal platelet levels showed no evidence of bone marrow suppression. Platelet survival was markedly decreased after 5 days of M-CSF (at the platelet count nadir) and after 9 days of continued M-CSF treatment, when the platelet count had returned to normal. Platelets from M-CSF-treated donors demonstrated normal survival when transfused into normal recipients. We concluded that thrombocytopenia produced by M-CSF was not due to suppression of thrombopoiesis, but to increased activity of the monocyte/macrophage system, which caused shortened platelet survival, and that subsequently, increased platelet production compensated for ongoing platelet destruction and resulted in normal platelet levels.

Adaptation, Physiological↗

Hematocrit value on intensive care unit entry influences the frequency of Q-wave myocardial infarction after coronary artery bypass grafting. The Institutions of the Multicenter Study of Perioperative Ischemia (McSPI) Research Group.

OBJECTIVES: No data exist regarding "the best" hematocrit value after coronary artery bypass graft surgery. Transfusion practice varies, because neither an optimal hematocrit value nor a uniform transfusion trigger criterion has been determined. METHODS: To investigate the optimal hematocrit value, we studied 2202 patients undergoing coronary bypass. The hematocrit value on entry into the intensive care unit (IHCT) was categorized into three groups: high (> or = 34%), medium (25% to 33%), and low (< or = 24%). Characteristics and adverse events (outcomes) were compared, and the effect of IHCT on the risk of myocardial infarction was determined by logistic regression. RESULTS: High IHCT (> or = 34%) was associated with an increased rate of myocardial infarction (8.3% vs 5.5% vs 3.6%; p < or = 0.03, high, medium vs low) and with more severe left ventricular dysfunction (11.7% vs 7.4% and 5.7%; p=0.006, high, medium vs low). Mortality rate increased with higher IHCT when all the high-risk subgroups were combined (8.6% vs 4.5% vs 3.2%; p < 0.001, high, medium vs low). By multivariate analysis, IHCT remained the most significant predictor of adverse outcomes (relative risk high vs low 2.22, 95% confidence interval: 1.04 to 4.76). No characteristic, event, medication, or transfusion therapy confounded the relationship between IHCT and outcome. CONCLUSION: High IHCT is associated with a higher rate of myocardial infarction and is an independent predictor of infarction. On the basis of the risk of myocardial infarction, there is no rationale for transfusion to an arbitrary level after coronary artery bypass grafting.

Anemia↗

Are overweight women at increased risk of obesity following pregnancy?

Longitudinal studies suggest that women who already have a high BMI are at greater risk of maternal obesity than their lighter counterparts. The aim of the present study was to investigate this possibility by examining the relationship between reproductive history and maternal BMI in a community of 627 women from South Africa with a high prevalence of obesity. Standardized questionnaires were used to obtain detailed sociodemographic and behavioural information, while maternal weight and height were both measured at the time of the interview. Analysis of covariance (ANCOVA) showed that maternal age (r2 0.015, P = 0.001), smoking status (r2 0.012, P = 0.036), and social support (r2 0.011, P = 0.006) were all independently associated with maternal BMI. If overweight women were at increased risk of maternal obesity, then the positive relationship between reproductive history and maternal BMI should be enhanced in this relatively obese community, yet the ANCOVA models showed no independent association between gravidity and maternal BMI after controlling for the effects of confounding factors. Although previous longitudinal studies have found a positive association between prepregnant weight and long-term weight gain, this relationship might arise because overweight women gain more weight over a fixed period of time than normal weight women, and therefore they may appear to be at greater risk of pregnancy-related weight gains. Overweight women are at greater risk of weight gain generally, but there is little unequivocal evidence to suggest that they are at any increased risk of maternal obesity, when compared with women of lower BMI.

Adult↗

Limulus antilipopolysaccharide factor prevents mortality late in the course of endotoxemia.

Limulus antilipopolysaccharide factor (LALF) can neutralize bacterial endotoxin, but its ability to prevent mortality following prolonged endotoxemia is unknown. Mice were challenged with an LD50 dose of intraperitoneal E. coli lipopolysaccharide (LPS) and then received LALF at various times after administration of LPS. Survival at 72 h was significantly improved by the administration of LALF at 4, 10, and even 24 h after LPS (73%, 78%, and 65% survival, respectively, vs. 15% survival in controls). Following intravenous administration of LALF at either 10 or 24 h after LPS, plasma levels of biologically active LPS abruptly fell (> 1000-fold lower than pre-LALF levels). Plasma LALF concentrations fell much more gradually in LPS-treated mice (t1/2 = 120 min) than in control mice (t1/2 = 2.5 min). In conclusion, LALF markedly decreased plasma concentrations of biologically active LPS and protected mice from lethality even when LALF was not administered until long after the onset of continuous endotoxemia.

Animals↗

Variability in transfusion practice for coronary artery bypass surgery persists despite national consensus guidelines: a 24-institution study. Institutions of the Multicenter Study of Perioperative Ischemia Research Group.

BACKGROUND: An estimated 20% of allogeneic blood transfusions in the United States are associated with cardiac surgery. National consensus guidelines for allogeneic transfusion associated with coronary artery bypass graft (CABG) surgery have existed since the mid- to late 1980s. The appropriateness and uniformity of institutional transfusion practice was questioned in 1991. An assessment of current transfusion practice patterns was warranted. METHODS: The Multicenter Study of Perioperative Ischemia database consists of comprehensive information on the course of surgery in 2,417 randomly selected patients undergoing CABG surgery at 24 institutions. A subset of 713 patients expected to be at low risk for transfusion was examined. Allogeneic transfusion was evaluated across institutions. Institution as an independent risk factor for allogeneic transfusion was determined in a multivariable model. RESULTS: Significant variability in institutional transfusion practice was observed for allogeneic packed red blood cells (PRBCs) (27-92% of patients transfused) and hemostatic blood components (platelets, 0-36%; fresh frozen plasma, 0-36%; cryoprecipitate, 0-17% of patients transfused). For patients at institutions with liberal rather than conservative transfusion practice, the odds ratio for transfusion of PRBCs was 6.5 (95% confidence interval [CI], 3.8-10.8) and for hemostatic blood components it was 2 (95% CI, 1.2-3.4). Institution was an independent determinant of transfusion risk associated with CABG surgery. CONCLUSIONS: Institutions continue to vary significantly in their transfusion practices for CABG surgery. A more rational and conservative approach to transfusion practice at the institutional level is warranted.

Blood Component Transfusion↗

Phat phacts.

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Body Composition↗