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S L Brown

Publications and source records attributed to S L Brown.

At least 73 records · Page 4Linked to original sources
PubMed1998

Are pediatric patients more susceptible to major renal injury from blunt trauma? A comparative study.

PURPOSE: We determine whether pediatric patients are more susceptible to major renal injury than adults. MATERIALS AND METHODS: We retrospectively reviewed the medical records of 34 consecutive children 2 to 17 years old (mean age 10) and 35 consecutive adults 19 to 59 years old (mean age 32) with blunt renal trauma who presented to our 2 level I trauma centers between 1990 and 1996. Patients with incomplete charts were excluded from study. According to the organ injury scaling committee of the American Association for the Surgery of Trauma renal injuries were graded based on computerized tomography results or laparotomy findings (4 adults) with major injuries classified as grade IV or V. Vascular injuries were excluded from study. Injury severity scores were calculated using the abbreviated injury scale. RESULTS: Injury severity scores ranged from 4 to 75 (mean 16) in the pediatric and 5 to 50 (mean 22) in the adult populations (p <0.01). Overall 16 of the 34 children (47%) and 8 of the 35 adults (23%) sustained major renal injuries (p <0.04). In 4 children who required surgical exploration for hemodynamic instability injury severity score ranged from 17 to 42 (mean 26) and all had major renal injuries. In 7 of the 35 adults (20%) who underwent surgical exploration because of hemodynamic instability and/or positive diagnostic peritoneal lavage injury severity score ranged from 22 to 50 (mean 34). Three of these 7 adults (42%) had major renal injuries and all had other visceral injuries at exploration. CONCLUSIONS: Children are more likely than adults to sustain renal injury from blunt abdominal trauma.

Adolescent↗
PubMed1997

Rupture of silicone-gel breast implants: causes, sequelae, and diagnosis.

Silicone-gel-filled breast implants have been widely used for breast augmentation and reconstruction after mastectomy. The rate of implant rupture and its sequelae are not known. We review the frequency, causes, sequelae, and detection of implant rupture. Materials testing of removed implants provides evidence that as implants age in vivo, they weaken and may rupture. Sequelae of rupture include migration of gel accompanied by inflammation and silicone granuloma formation. The role of free silicone gel in relation to idiopathic or atypical connective tissue disease is not clear. Magnetic resonance imaging is substantially more sensitive in the detection of rupture than is mammography or ultrasonography.

Breast Implants↗
PubMed1997

Breast implants and cancer.

BACKGROUND: Although silicone breast implants have been linked to various short-term complications, less is known about their long-range effects. Most attention has focused on connective tissue disorders, but the range of immunologic disturbances observed in women with implants suggests that consideration also be given to other chronic diseases, including cancer. The greatest attention has focused on breast cancer, given clinical reports suggesting an association and observations that mammographic visualization is deterred by implants. Findings from epidemiologic studies, however, actually suggest that breast cancer risk might be reduced among women with implants, although the biologic mechanism remains undefined. In addition, most studies do not suggest that women with breast implants have more advanced breast cancer at diagnosis or a worse prognosis than those without implants. The majority of studies have focused on women who received implants for cosmetic reasons, with little previous investigation of women who received implants for breast reconstruction following cancer surgery. In terms of other cancers, animal as well as clinical data suggest potential risks of sarcomas and hematologic cancers, including multiple myeloma. The risk of these cancers has not yet been adequately addressed by epidemiologic studies, although several ongoing studies should provide insights. It will be important for studies to consider effects of other lifestyle factors as well as to analyze relationships according to duration of implantation, a demonstrated determinant of implant deterioration. In addition, consideration should be given to type of implant, including implants with polyurethane foam covers, which can leak toluene diamine, a demonstrated carcinogen in animals.

Breast Implants↗
PubMed1997

Recombinant methionyl human stem cell factor and filgrastim for peripheral blood progenitor cell mobilization and transplantation in non-Hodgkin's lymphoma patients--results of a phase I/II trial.

To examine the safety and efficacy of recombinant-methionyl human stem cell factor (r-metHuSCF), 38 patients with intermediate-grade or immunoblastic high-grade non-Hodgkin's lymphoma who were eligible for autologous transplantation were randomized to receive r-metHuSCF (5, 10, 15, or 20 microg/kg/d) plus Filgrastim (10 microg/kg/d) or Filgrastim (10 microg/kg/d) alone to mobilize peripheral blood progenitor cells. Subcutaneous administration of r-metHuSCF was well tolerated in conjunction with a multi-agent pre-medication regimen; local injection site reactions were the most commonly seen adverse event. The total mononuclear cell count, CD34+ cell content, granulocyte-macrophage colony-forming cells (GM-CFC), and burst-forming units-erythroid (BFU-E) per kilogram in the apheresis product was similar when all patients were analyzed by treatment cohort and mobilization regimen (Filgrastim or r-metHuSCF in combination with Filgrastim); however, when prior chemotherapy was taken into account in a supplementary analysis, clinically important differences were observed. Extensive prior therapy was defined as the amount of exposure to specific stem cell toxic chemotherapeutic agents that patients received. These agents include procarbazine, nitrogen mustard, melphalan, nitrosoureas (> or = 2 cycles of any of these drugs) or greater than 7.5 g of cytosine arabinoside. In these patients, there was an increased number of CD34+ cells (1.76 v 0.28 x 10(6)/kg), GM-CFC (20.5 v 5.0 x 10(4)/kg), and BFU-E (36.9 v 8.9 x 10(4)/kg) in patients receiving r-metHuSCF and Filgrastim (N = 18) compared with Filgrastim alone (N = 5). These patients also had a decreased time to an untransfused platelet count of 20 x 10(9)/L that was 10.5 days shorter in the patients who received r-metHuSCF and Filgrastim (12.5 v 23 days). These differences were not found to be statistically significant, possibly because of small size, but are clinically important.

Adult↗
PubMed1997

Atmospheric and potable water exposures to methyl tert-butyl ether (MTBE).

This paper presents information on the ways in which people can be exposed to methyl tert-butyl ether (MTBE) via air and water and on the distribution of doses that can result from those exposures. Data on concentrations of MTBE in air were complied for 15 different occupational, commuting, or residential exposure categories, and concentrations in potable water were complied from five states in the MTBE-using areas of the United States. Based on these concentrations and characteristics of the exposed populations, average daily and lifetime average doses were estimated. Both the concentration data and several of the population characteristics were estimated as distributions rather than as point values so that the numbers of people exposed at various levels could be estimated. Arithmetic mean occupational doses via air were in the range of 0.1 to 1.0 mg/kg-day, while doses from residential exposures, commuting, and refueling were in the range of 0.0004 to 0.006 mg/kg-day. Lifetime doses for workers were in the range 0.01 to 0.1 mg/kg-day. The cumulative dose distribution for the entire population of the MTBE-using regions of the United States was estimated by combining the distributions of doses and the numbers of people in each exposure category. In the MTBE-using areas, arithmetic mean doses via air were estimated to be 0.0053 and 0.00185 mg/kg-day for the chronic and lifetime cases, respectively. Approximately 98.5% of the population living in MTBE-using regions uses water with concentrations affected only by atmospheric deposition, if at all, and too low to be detected with current methods (< 2 micrograms/liter). The remaining population uses water with an estimated geometric mean concentration of 0.36 microgram/liter, an arithmetic mean concentration of 49 micrograms/l, and a 95th percentile concentration of 64 micrograms/liter. Doses via ingestion, inhalation, and dermal absorption were included. The estimated arithmetic mean dose for the population exposed via water was 1.4 x 10(-3) mg/kg-day.

Air Pollutants↗
PubMed1997

Anti-P-selectin antibody decreases inflammation and thrombus formation in venous thrombosis.

PURPOSE: Venous thrombosis and inflammation are interrelated. P-selectin contributes to activation of leukocyte-mediated inflammation. Therefore, we hypothesized that the neutralization of P-selectin would decrease vein wall inflammation and thrombosis. METHODS: Twelve baboons underwent infrarenal inferior vena caval balloon occlusion to induce thrombosis. Two groups of four baboons received neutralizing intravenous anti-P-selectin antibody (PSab) GA6 or CY1748 before occlusion and at days 2 and 4. Four baboons received saline control injections. One baboon per group was killed at days 2, 6, and 13, and at 2 months. Analysis included phlebography, ultrasound, gadolinium (Gd)-enhanced magnetic resonance venography (reflecting vein wall inflammation), and histologic, morphometric, and protein evaluation of the vein wall. Thrombus presence or absence was assessed. RESULTS: By day 2 in PSab baboons, vein wall Gd enhancement was decreased in the mid-inferior vena cava and the right iliac vein (p < 0.05; GA6 vs control baboons), normalizing by 2 months. The mid-inferior vena cava revealed fewer neutrophils and total leukocytes in PSab baboons; however, for GA6 in the right iliac vein these decreases were not present despite the absence of Gd enhancement; they were decreased with CY1748. PSab baboons demonstrated significantly less thrombus than control baboons (p < 0.01, GA6 and CY1748 vs control baboons). CONCLUSIONS: Anti-P-selectin antibody decreases vein wall inflammation and thrombus formation. Inhibition of P-selectin may be useful in venous thrombosis prophylaxis.

Acute Disease↗
PubMed1997

Phytoremediation of soil metals.

The phytoremediation of metal-contaminated soils offers a low-cost method for soil remediation and some extracted metals may be recycled for value. Both the phytoextraction of metals and the phytovolatilization of Se or Hg by plants offer great promise for commercial development. Natural metal hyperaccumulator phenotype is much more important than high-yield ability when using plants to remove metals from contaminated soils. The hypertolerance of metals is the key plant characteristic required for hyperaccumulation; vacuolar compartmentalization appears to be the source of hypertolerance of natural hyperaccumulator plants. Alternatively, soil Pb and Cr6+ may be inactivated in the soil by plants and soil amendments (phytostabilization). Little molecular understanding of plant activities critical to phytoremediation has been achieved, but recent progress in characterizing Fe, Cd and Zn uptake by Arabidopsis and yeast mutants indicates strategies for developing transgenic improved phytoremediation cultivars for commercial use.

Biological Transport, Active↗
PubMed1997

Preferential radiosensitization of 9L glioma cells transduced with HSV-tk gene by acyclovir.

The antiviral drug acyclovir, an analogue of purine, was found to selectively enhance the radiosensitivity of rodent tumor cells which were transduced with the herpes simplex virus thymidine kinase gene (HSV-tk). 9L rat glioma cells transduced with HSV-tk and treated with acyclovir (20 micrograms/ml) for 24 hr before or after irradiation were highly sensitive to radiation, as compared with non-transduced glioma cells. When 9L cells transduced with HSV-tk gene were exposed to acyclovir and radiation, the sensitizer enhancement ratio (SER) was 1.6. In vivo, a significant increase in the median survival time of rats with 9L-tk tumors was observed when acyclovir was administered before and after single-dose irradiation, relative to the survival time of similar rats receiving radiation alone. The results show that an antiviral agent can selectively enhance cell killing by radiation in cells transduced with the HSV-tk, and suggest that the addition of HSV-tk gene therapy to standard radiation therapy will improve the effectiveness of treatment for brain tumors.

Acyclovir↗
PubMed1997

Prevalence and effectiveness of self-regulatory techniques used to avoid drunk driving.

Research suggests that drinkers often use personal self-regulatory techniques to avoid drunk driving. A population-representative sample of 427 people at high risk of drunk driving were interviewed to examine the extent to which they used self-regulatory techniques. Most popular techniques were limiting drinks to a predetermined number, organizing another driver, catching a taxi, and spontaneously delaying or avoiding driving after alcohol has been consumed. After controlling exposure to demographic and drinking behavior variables, limiting drinks to a predetermined number was the only technique associated with a reduced likelihood of drunk driving. Respondents who used taxis and drank low-alcohol beer were more likely to report drunk driving, as were those who spontaneously decided to delay or avoid driving after drinking. Although interpretation of the findings is constrained by the cross-sectional survey methodology, further investigations may lead to the development of countermeasures which promote the use of appropriate techniques.

Accidents, Traffic↗
PubMed1997

Psychopathy and sexual assault: static risk factors, emotional precursors, and rapist subtypes.

This study compared psychopathic and nonpsychopathic rapists on static risk factors and on emotional and motivational precursors. Sixty incarcerated rapists were assessed for psychopathy with the Psychopathy Checklist--Revised (R. D. Hare, 1991), and they were classified according to the Massachusetts Treatment Center: Revised Rapist Typology, Version 3 (R. A. Knight & R. A. Prentky, 1990b). Psychopathy was positively associated with past nonsexual offenses and negatively associated with age onset for criminal offending, number of sexual victims, and the intensity of negative emotions experienced before sexual offending. However, psychopathy was not related to sexual offense history, age of onset for sexual offending, or victim harm. Last, psychopaths were most likely to be classified as opportunistic and pervasively angry rapists. The findings indicate that psychopathy should be considered when developing intervention strategies for rapists.

Adult↗
PubMed1997

Genotype-specific transcriptional regulation of PAI-1 expression by hypertriglyceridemic VLDL and Lp(a) in cultured human endothelial cells.

The hypothesized relationships between plasminogen activator inhibitor (PAI-1) genotypes, PAI-1 levels, and their potential regulation by hypertriglyceridemic (HTG) very low density lipoprotein (VLDL) and lipoprotein(a) [Lp(a)] was examined in a PAI-1 genotyped human umbilical vein endothelial cell (HUVEC) culture model system. Individual human umbilical veins were used to obtain cultured ECs and were genotyped for PAI-1 by using the HindIII restriction fragment length polymorphism (RFLP) as a marker for genetic variation. Digested genomic DNA, examined by Southern blot analysis and probed with an [alpha-32P]dCTP-labeled 2.2-kb PAI-1 cDNA, yielded three RFLPs designated 1/1 (22-kb band only), 1/2 (22-plus 18-kb bands), and 2/2 (18-kb band only). Individual PAI-1 genotyped HUVEC cultures were incubated in the absence or presence of HTG-VLDL (0 to 50 micrograms/mL) or Lp(a) (0 to 50 micrograms/mL) at 37 degrees C for various times (4 to 24 hours), followed by analyses of PAI-1 antigen (by ELISA) and mRNA (by ribonuclease protection assay) levels, EC surface-localized plasmin generation assays, and nuclear run-on transcription assays. Secreted PAI-1 antigen levels were increased approximately 2- to 3-fold by HTG-VLDL and approximately 1.6 to 2-fold by Lp(a); mRNA levels were increased approximately 3- to 4.5-fold by HTG-VLDL and approximately 2.5- to 3.2-fold by Lp(a) compared with medium-incubated controls, primarily in the 2/2 PAI-1 genotype HUVEC cultures. Increases in PAI-1 mRNA induced by HTG-VLDL or Lp(a) could be abolished by coincubation with actinomycin D (2 x 10(-6) mol/mL) or puromycin (1 microgram/mL). In addition, nuclear transcription run-on assays typically demonstrated that HTG-VLDL increased PAI-1 gene transcription rates by approximately 5- to 6-fold and approximately 4- to 5-fold, respectively, primarily in the 2/2 PAI-1 genotype HUVEC cultures compared with 1/1 PAI-1 genotype HUVEC cultures or medium-incubated controls. The positive control interleukin-1 increased both 2/2 and 1/1 PAI-1 mRNA levels by approximately 5- to 6-fold. Increased PAI-1 antigen and mRNA expression were associated with a concomitant 50% to 60% decrease in plasmin generation. These combined results demonstrate the genotype-specific regulation of PAI-1 expression by HTG-VLDL and Lp(a) and further indicate that these risk factor-associated components regulate PAI-1 gene expression at the transcriptional level in cultured HUVECs. Results from these studies further suggest that individuals with this responsive 2/2 PAI-1 genotype may reflect the additional inherent potential for later HTG-VLDL- or Lp(a)-induced fibrinolytic dysfunction, resulting in the early initiation of thrombosis, atherogenesis, and coronary artery disease.

Arteriosclerosis↗
PubMed1997

Distinguishing left ventricular aneurysm from pseudoaneurysm. A review of the literature.

A postmyocardial infarction left ventricular pseudoaneurysm occurs when a rupture of the ventricular free wall is contained by overlying, adherent pericardium. A postinfarction aneurysm, in contrast, is caused by scar formation resulting in thinning of the myocardium. Although the usual treatment for patients with pseudoaneurysm is urgent surgical repair, the imaging characteristics of pseudoaneurysm and aneurysm, for which treatment is more conservative, are quite similar. The literature on the natural history and imaging characteristics of the two entities is reviewed, and an approach to distinguishing between the two entities is proposed.

Aged↗
PubMed1997

Beneficiary centered care in services to persons with developmental disabilities.

This article provides an overview of the findings from the Evaluation of Medicaid's Community Supported Living Arrangements (CSLA) Program. Results suggest that CSLA provided a useful model of beneficiary centered care for persons with developmental disabilities. The implications of the findings of this evaluation for current management of Medicaid programs are discussed.

Community Health Services↗
PubMed1997

Reinterpreting the empathy-altruism relationship: when one into one equals oneness.

Important features of the self-concept can be located outside of the individual and inside close or related others. The authors use this insight to reinterpret data previously said to support the empathy-altruism model of helping, which asserts that empathic concern for another results in selflessness and true altruism. That is, they argue that the conditions that lead to empathic concern also lead to a greater sense of self-other overlap, raising the possibility that helping under these conditions is not selfless but is also directed toward the self. In 3 studies, the impact of empathic concern on willingness to help was eliminated when oneness--a measure of perceived self-other overlap--was considered. Path analyses revealed further that empathic concern increased helping only through its relation to perceived oneness, thereby throwing the empathy-altruism model into question. The authors suggest that empathic concern affects helping primarily as an emotional signal of oneness.

Altruism↗
PubMed1996

Reported complications of silicone gel breast implants: an epidemiologic review.

PURPOSE: To review the range of local and systemic complications attributed to silicone breast implants and to evaluate the epidemiologic literature on these complications. DATA SOURCES: Epidemiologic studies of the potential risks of silicone breast implants identified by MEDLINE search and literature review. STUDY SELECTION: Epidemiologic studies with cohort, case-control, and cross-sectional designs. When epidemiologic studies were unavailable (as for estimates of local complications), case series were reviewed. DATA EXTRACTION: Epidemiologic studies evaluated for methodologic quality, including such characteristics as study design, sample size and selection, determination of silicone exposure and outcome variables, and duration of follow-up. DATA SYNTHESIS: The epidemiologic literature on the potential complications of silicone breast implants has concentrated primarily on connective tissue disorders and cancer. Estimated of the true incidence of local complications, such as rupture, capsular contracture, and breast pain, are unavailable. Studies of scleroderma and other defined connective tissue diseases suggest that implant recipients have no substantially increased risk for these disorders; however, the epidemiologic literature is insufficient to rule out an association between breast implants and connective tissue disease-like syndromes. Overall, the rate of breast cancer does not seem to be increased in women with silicone breast implants. However, the risk to women as they reach the postmenopausal years in not yet known. CONCLUSIONS: Information is insufficient to adequately advise women who currently have or are seeking to obtain breast implants about the overall risk of these devices. No epidemiologic study has indicated that the rate of well-defined connective tissue disease or breast cancer has greatly increased in women with silicone breast implants, but no studies have ruled out a moderately increased risk for these diseases. No studies have adequately addressed the crucial issue of local complications such as rupture and capsular contracture, although evidence increasingly points to a higher risk for rupture as implants age.

Breast Implants↗