Biomedical subjects

S Rauch

Publications and source records attributed to S Rauch.

At least 37 records · Page 2Linked to original sources

PubMed1997

Achievement and safety of a low blood pressure goal in chronic renal disease. The Modification of Diet in Renal Disease Study Group.

The Modification of Diet in Renal Disease Study showed a beneficial effect of a lower-than-usual blood pressure (BP) goal on the progression of renal disease in patients with proteinuria. The purpose of the present analyses was to examine the achieved BP, baseline characteristics that helped or hindered achievement of the BP goals, and safety of the BP interventions. Five hundred eighty-five patients with baseline glomerular filtration rate between 13 and 55 mL/min per 1.73 m2 (0.22 to 0.92 mL/s per 1.73 m2) were randomly assigned to either a usual or low BP goal (mean arterial pressure < or = 107 or < or = 92 mm Hg, respectively). Few patients had a history of cardiovascular disease. All antihypertensive agents were permitted, but angiotensin-converting enzyme inhibitors (with or without diuretics) followed by calcium channel blockers were preferred. The mean (+/- SD) of the mean arterial pressures during follow-up in the low and usual BP groups was 93.0 +/- 7.3 and 97.7 +/- 7.7 mm Hg, respectively. Follow-up BP was significantly higher in subgroups of patients with preexisting hypertension, baseline mean arterial pressure > 92 mm Hg, a diagnosis of polycystic kidney disease or glomerular diseases, baseline urinary protein excretion > 1 g/d, age > or = 61 years, and black race. The frequency of medication changes and incidence of symptoms of low BP were greater in the low BP group, but there were no significant differences between BP groups in stop points, hospitalizations, or death. When data from both groups were combined, each 1-mm Hg increase in follow-up systolic BP was associated with a 1.35-times greater risk of hospitalization for cardiovascular or cerebrovascular disease. Lower BP than usually recommended for the prevention of cardiovascular disease is achievable by several medication regimens without serious adverse effects in patients with chronic renal disease without cardiovascular disease. For patients with urinary protein excretion > 1 g/d, target BP should be a mean arterial pressure of < or = 92 mm Hg, equivalent to 125/75 mm Hg.

Adolescent↗

PubMed1996

Localization of syntactic comprehension by positron emission tomography.

Positron Emission Tomography (PET) was used to determine regional cerebral blood flow (rCBF) when eight normal right-handed males read and made acceptability judgments about sentences. rCBF was greater in Broca's area (particularly in the pars opercularis) when subjects judged the semantic plausibility of syntactically more complex sentences as compared to syntactically less complex sentences. rCBF was greater in left perisylvian language areas when subjects had to decide whether sentences were semantically plausible than when subjects had to decide whether syntactically identical sentences contained a nonsense word. The results of this experiment suggest that overall sentence processing occurs in regions of the left perisylvian association cortex. The results also provide evidence that one particular aspect of sentence processing (the process that corresponds to the greater difficulty of comprehending center-embedded than right-branching relative clause sentences) is centered in the pars opercularis of Broca's area. This process is likely to be related to the greater memory load associated with processing center-embedded sentences.

Adult↗

PubMed1996

Prevalence of hypertension in 1,795 subjects with chronic renal disease: the modification of diet in renal disease study baseline cohort. Modification of Diet in Renal Disease Study Group.

The Modification of Diet in Renal Disease Study was a multicenter trial of the effect of protein restriction and strict blood pressure control on the progression rate of chronic renal failure of multiple causes. At the first baseline visit, 1,795 screened patients with renal disease had blood pressure measured, antihypertensive medications recorded, glomerular filtration rate (GFR) determined by 125I-iothalamate clearance, a nutritional assessment, and a 24-hour urine collection to determine sodium and potassium levels. A total of 1,494 patients in this cohort were classified as hypertensive (83%) and the remainder (301 patients) as nonhypertensive. Ninety-one percent of the hypertensive subjects were on treatment, 54% being controlled to a blood pressure of < or = 140/90 mm Hg. To better understand the factors that contribute to the development of hypertension in chronic renal disease, some determinants of the prevalence of hypertension in this cohort were investigated. Compared with normotensive subjects, hypertensive patients were older (51.2 +/- 12.7 years v 46.6 +/- 13.1 years [mean +/- SD]), had a higher body mass index (BMI; 27.5 +/- 4.7 kg/m2 v 25.4 +/- 4.2 kg/m2), and had a lower GFR (37.8 +/- 19.6 mL/min/1.73 m2 v 50.1 +/- 25 mL/min/1.73 m2). All these differences were significant (P < 0.01). The prevalence of hypertension was significantly higher for men than for women (86% v 80%; P = 0.001), and for blacks than for whites (93% v 81%; P < 0.001). The prevalence of hypertension was higher in subjects with glomerular disease than in those with tubulointerstitial disease (85% v 62.6%; P < 0.001). The prevalence of hypertension varied inversely with GFR (from 66% at a GFR of 83 mL/min/1.73 m2 to 95% at a GFR of 12 mL/min/1.73 m2). The prevalence of hypertension varied directly with BMI (from 70% with a BMI at the 10th percentile to 94% with a BMI at the 97th percentile). This relationship was independent of GFR. Multiple logistic regression analysis showed five predictors in decreasing order of significance as determined by chi-square values: GFR, 83.2; BMI, 36.7; black race, 19.9; increasing age, 14.5 (all P < 0.001); and male gender, 5.1 (P = 0.024). Salt intake was not a determinant of blood pressure status. These results confirm previous reports indicating that hypertension in renal disease is determined by the level of renal function. For the first time, three factors known to predict blood pressure levels in populations with normal renal function were also shown to be determinants of blood pressure in renal disease: BMI, black race, and age. In addition, the data suggest that hypertension is inadequately treated in more than half of patients with chronic renal disease in the United States.

Adolescent↗

PubMed1996

Clearing of psoriasis by a novel immunosuppressive macrolide.

Accumulating evidence suggests that psoriasis may be a genetically determined immunogenic, inflammatory disorder based on an ongoing autoreactive Th-1 response. Systemic immunosuppressive therapy is highly effective but fraught with longterm side effects. Our research therefore focuses on therapeutic strategies that induce local immunosuppression in the skin by topical, transepidermal delivery of immunosuppressive drugs. SDZ 281-240 is a newly developed macrolide of the ascomycin type. It is immunosuppressive by mechanism of action similar to that of FK506 but has no antiproliferative activity against keratinocytes in vitro. To evaluate whether SDZ 281-240 exhibits antipsoriatic activity when applied topically, we tested 15 patients with severe, recalcitrant psoriasis, using a microplaque assay in randomized, double-blind, placebo-controlled study, comparing the therapeutic efficacy of the macrolide with a potent halogenated corticosteroid and vehicle. All patients showed a significant improvement of psoriatic lesions treated with two concentrations of the macrolide and, as expected, with the corticosteroid but not with placebo. Both concentrations of the macrolide led to clearing of psoriasis after 10 days of treatment and biopsies confirmed a reversal of the histopathological and immunopathological phenotype of psoriasis to that of normal skin. Thus, an immunosuppressive agent that interferes with early T cell activation can be designed to penetrate into psoriatic lesions when applied topically and to be functionally active within the skin to suppress the ongoing psoriatic process.

Administration, Topical↗

PubMed1995

Effects of penicillin, ceftriaxone, and doxycycline on morphology of Borrelia burgdorferi.

Antibiotic therapy with penicillin, doxycycline, and ceftriaxone has proven to be effective for the treatment of Lyme borreliosis. In some patients, however, it was noticed that borreliae can survival in the tissues in spite of seemingly adequate therapy. For a better understanding of this phenomenon, we investigated the different modes of degeneration of Borrelia burgdorferi suspensions during a 96-h exposure to various antibiotics. By dark-field microscopy and ultrastructural investigations, increasing blebbing and the gradual formation of granular and cystic structures could be followed during the exposure time. Although antibiotic concentrations at the MIC at which 90% of organisms are inhibited after 72 h were 80% or even greater, motile organisms were still present after incubation with penicillin and doxycycline but not after incubation with ceftriaxone. By transmission electron microscopy, intact spirochetal parts, mostly situated in cysts, were seen up to 96 h after exposure with all three antibiotics tested. According to experiences from studies with other spirochetes it is suggested that encysted borreliae, granules, and the remaining blebs might be responsible for the ongoing antigenic stimulus leading to complaints of chronic Lyme borreliosis.

Borrelia burgdorferi Group↗

PubMed1994

Community hospitals and the Internet: lessons from pilot connections.

Community hospitals in rural and isolated areas have had little access to the Internet. In 1992, the National Library of Medicine funded a pilot project to be conducted by the University of Washington and seven community hospitals in the northwestern United States. The goals of the project were to connect the hospitals to the Internet and study the uses made of this resource. A number of administrative, technical, financial, and organizational problems were dealt with in the attempt to establish the Internet connections and introduce this resource to these health care settings. This paper examines these issues and presents conclusions drawn from the experiences of the project team.

Computer Communication Networks↗

PubMed1991

A dual-frequency circularly polarizing whole-body MR antenna for 69/170 MHz.

The design concept of a dual-frequency whole-body MR antenna for circular polarization is presented. First, the principle of the capacitively shortened transmission line antenna, which is the basis of the design, is discussed. Emphasis is given to the antenna design at high frequencies. Two variants of possible antenna constructions are described and the RF efficiency is calculated for both frequencies. The antenna performance is discussed for the example of 69 and 170 MHz, the nuclear magnetic resonance frequencies of the nuclei 31P and 1H at 4 T. For 31P experiments, a whole-body antenna is useful only for transmitting and, thus, the antenna performance can be optimized for 1H. The design principle is not limited to two frequencies; however, the RF efficiency decreases with an increasing number of resonance frequencies. Results of a laboratory version and 1H images at 4 T are presented.

Biomedical Engineering↗

PubMed1990

Neuropathological changes in transgenic mice carrying copies of a transcriptionally activated Mos protooncogene.

Independent transgenic mouse lines carrying the mouse Mos protooncogene linked to a retroviral transcriptional control sequence display behavioral abnormalities including circling, head tilting, and head bobbing. This dominant phenotype shows various degrees of penetrance in different transgenic founder animals and lines. Neuronal and axonal degeneration, gliosis, and inflammatory infiltrates are found in all transgenic mouse lines in which behavioral traits are present. Recordings of auditory-evoked potentials in mice of one of these lines demonstrate that transgenic mice are deaf; in these mice spiral ganglia degenerate and most of the cochlear hair cells are absent. By using an S1 nuclease protection assay, we have detected RNA expression of the transgene in all tissues examined and, in particular, at high levels in brain. In situ hybridization experiments show that Mos expression can be detected in specific areas of the central nervous system. Lesions are present in areas with demonstrable overexpression of Mos.

Animals↗

PubMed1988

Effects of short-term prenatal alcohol exposure on neuronal membrane order in rats.

Long-Evans rat dams were treated with ethanol (4 g/kg, twice daily) by gavage on gestational days 10-14. This dosage schedule has been shown to produce significant behavioral and ponderal teratogenicity. Pair-fed dams were gavaged with isocaloric amounts of sucrose. All offspring were reared by untreated, surrogate dams. Pups were sacrificed on days 3 and 28, and whole brain neuronal plasma membranes were prepared for analysis by a fluorescence polarization technique using 1,6-diphenyl-1,3,5-hexatriene as the membrane probe. On day 3, steady-state anisotropy was significantly decreased in the ethanol-treated pups. Arrhenius plots revealed that this difference was associated with a change on both membrane entropy and enthalpy. By day 28, the differences between groups disappeared. These data would be consistent with the view that the brief gestational ethanol exposure delays neuronal maturation.

Animals↗

PubMed1988

Abuse, feelings, and health behaviors in a student population.

Behavioral sequelae of child abuse are frequently cited, but there are few studies that examine the strength of association between behavioral effect and abuse for children in a nonclinical setting. Seven hundred twelve junior high school students (mean age, 13.5 years) were surveyed for self-report of personal experience with abuse, certain health behaviors, and self-esteem. Physical and/or sexual abuse was reported by 18.3% of students. Both types of abuse were associated with the following behaviors: running away; considering hurting oneself; suicide attempts; and the use of drugs, pot (marijuana), cigarettes, and laxatives. No clinically significant relationships were found between abuse and report of anger, sadness, or self-esteem. These data suggested that some feelings and behaviors were common among all adolescents sampled, while others were more common among abused adolescents. Recognition of strong associations should help direct clinical management. The results of this study confirm findings from some previous reports and indicate the need for further studies of children who are not in a clinical setting.

Adolescent↗

PubMed1980