Search PubMed⌕ Search

Biomedical subjects

S Roberts

Publications and source records attributed to S Roberts.

At least 235 records · Page 13Linked to original sources
PubMed1993

Clozapine response and adverse effects in nine brain-injured patients.

Clozapine was used to treat nine brain-injured patients with psychotic symptoms or outbursts of rage and aggression refractory to other medications. Verbal and physical aggression decreased markedly in two patients, and one additional patient had a dramatic decrease in bizarre behaviors. Mild improvement occurred in three patients with a decrease in agitation and frequency of auditory hallucinations. Response was indeterminate in three patients because of inadequate length of treatment. The incidence of side effects appeared to be higher than expected, with seizures occurring in two of nine patients. These case reports illustrate that clozapine may be useful in the treatment of psychosis and aggressive behavior after brain injury, despite the occurrence of adverse effects.

Activities of Daily Living↗
PubMed1993

Effect of "standing" on spasticity, contracture, and osteoporosis in paralyzed males.

The effect of "standing" in a frame on spasticity (clinical assessment and H-reflex), contracture (lower extremity joint range of motion), and osteoporosis (dual photon absorptiometry) was studied in six paralyzed males (mean age 49 yr) who had been confined to wheelchairs for an average of 19 years. Standing time averaged 144 hours over a mean of 135 days. Clinical Assessment measured reflexes, tone, and clonus in the legs. Results revealed no important differences between initial and final scores for clinical assessment and joint range of motion. In three subjects for whom H-reflexes were found, latency and amplitude were not altered by "standing." Bone density was normal in the lumbar spine but significantly reduced in the femoral neck. "Standing" did not modify the bone density in any site. A follow-up interview revealed that 67% of subjects continued to "stand" and felt healthier because of it. In summary, "standing" had no ill effects, did not alter measured variables, and had a positive psychological impact.

Absorptiometry, Photon↗
PubMed1993

The microbiology of post-cesarean wound morbidity.

OBJECTIVE: To determine the microbiology of wound morbidity following cesarean deliveries. METHODS: Nine hundred thirty-nine wounds in post-cesarean patients were followed prospectively. Aspirates from the abdominal incision were collected if the wounds developed erythema, induration, or pain and had demonstrable fluid collection noted on ultrasound. Cultures were also obtained of wound exudates when there was spontaneous separation of the skin. Gram stains were performed concomitantly with culture. RESULTS: The cumulative incidence of post-cesarean wound morbidity between September 1990 and June 1991 was 6.9% (65 of 939), and the rate of culture-positive wounds was 72% (47 of 65). Ureaplasma urealyticum was the most frequent isolate at a rate of 62% (29 of 47), followed by coagulase-negative staphylococci at 32% (15 of 47) and Enterococcus faecalis at 28% (13 of 47). Gram stains of the exudates obtained were used to predict microbiologic results. Organisms present on Gram stain yielded a sensitivity of 0.55, specificity of 1.0, positive predictive value of 1.0, and negative predictive value of 0.71 when used to predict positive culture results for bacterial wound infection other than with genital mycoplasmas. White blood cell counts greater than ten per 400x high-power fields yielded a sensitivity of 0.83, specificity of 0.72, positive predictive value of 0.89, and negative predictive value of 0.62 when used to predict wound infection including genital mycoplasmas. CONCLUSIONS: Genital mycoplasmas are the most prevalent bacterium in post-cesarean wound infections in this population. If genital mycoplasmas are pathogenic in this setting, then the Gram stain may be useful in predicting wound microbiology. More research is needed on the pathogenic role of genital mycoplasmas in wound infections.

Adult↗
PubMed1993

Analysis of behavior state conditions and associated environmental variables among students with profound handicaps.

State conditions in combination with environmental events and factors significantly affect the level of alertness and responsiveness among students with profound and multiple handicaps. State conditions and environmental variables over a continuous, 5-hour period for each of 25 students in classroom settings were measured. Data were assessed using transitional probability, time series, and correspondence analysis procedures. Results showed the presence of state sequence patterns, short state change periods, and a relatively small amount of association between specific behavior states and the environmental factors and events measured in the study.

Adolescent↗
PubMed1992

Phenotypic evidence for a common pathogenesis in X-linked deafness pedigrees and in Xq13-q21 deletion related deafness.

A structural cochlear abnormality has been observed by high resolution CT scanning in some families where X-linked deafness is segregating. We now present evidence that the same abnormality is present in a deaf patient who has a deletion within Xq21. This observation provides phenotypic evidence that the genotypic basis of deafness is the same in both patient groups. It is also likely that the perilymphatic fluid "gusher" abnormality may be common to both.

Child↗
PubMed1992

Sudden acquired retinal degeneration ('silent retina syndrome') in two dogs.

Two unrelated adult dogs developed idiopathic, acute-onset, bilateral total blindness. The ophthalmoscopic changes were minimal and no electroretinographic response could be detected in either dog. The retinas were examined ultrastructurally 10 days (dog 1) and two-and-a-half months (dog 2) after they became blind. There was widespread loss of the outer segments of rod and cone photoreceptors. Where the outer segments persisted, there was marked tubulovesicular change with loss of normal orientation in their lamellae. Second order neurons (bipolar cells) and ganglion cells were unaffected. The cause of this selective and massive disruption of rod and cone endings was not established, but acute toxicity is proposed as a possible mechanism.

Animals↗
PubMed1992

Distinct modes of transcription read through or terminate at the c-myc attenuator.

Premature termination of transcription by RNA polymerase II (pol II) occurs in the 5' region of many viral and cellular genes. Modulation of this process, or attenuation, is an important means of transcriptional control, but its mechanism is unknown. Using injected Xenopus oocytes, the efficiency of the mouse c-myc attenuator was tested when it was placed at various distances from the transcription initiation site. The attenuator functioned with each of six different pol II promoters tested; however, termination efficiency declined markedly when it was placed more than approximately 400 bases from the start site. This decline in attenuator function with distance from the start site coincided with increased sensitivity to the pol II inhibitor 5,6-dichloro-1-beta-D-ribofuranosyl benzimidazole (DRB). Thus transcription complexes situated further from the promoter appear to have a lower ability to recognize the attenuator and a greater sensitivity to DRB. Furthermore, polymerases which have read through one attenuation site have a reduced ability to terminate at a second site. The results imply that a discrete subset of elongation complexes is capable of premature termination, and that this subset exists only within the first few hundred bases of the transcription unit. Regulation of termination efficiency may be effected by changing the balance between the two modes of transcription committed either to read through or to terminate prematurely.

Animals↗
PubMed1992

New method of automated sleep quantification.

Since its discovery some 50 years ago, the electro-encephalogram (EEG) has formed the basis for classification of sleep into several stages, either laboriously performed by visual examination of the EEG and related signals or, more recently, by automated techniques. Both visual scoring and most automated analyses are highly subjective and rely on application of a predefined set of rules. A method of analysing the EEG which requires no such application of rules and aims to give some indication of the dynamics of sleep in humans is proposed in the paper.

Adult↗
PubMed1992

Influence of the electrical stimulation of the medial amygdala on adrenocortical sensitivity to adrenocorticotrophin in hypophysectomized rats.

The effects of electrical stimulation of medial amygdala on the adrenocortical sensitivity to adrenocorticotrophin (ACTH) were investigated in hypophysectomized rats. The intravenous injection of ACTH increased the rates of 14C transfer from 14C-l-acetate into corticosterone and cortisol in the adrenal slices of hypophysectomized rats. The electrical stimulation of the medial amygdala produced a further increase in the rates of 14C transfer from 14C-l-acetate into corticosterone and cortisol. From these results, it might be suggested that the medial amygdala was capable of enhancing the adrenocortical steroidogenesis in response to ACTH.

Acetates↗
PubMed1992

Quantitative oropharyngeal Epstein-Barr virus shedding in renal and cardiac transplant recipients: relationship to immunosuppressive therapy, serologic responses, and the risk of posttransplant lymphoproliferative disorder.

Epstein-Barr virus (EBV) infection plays a major role in the pathogenesis of posttransplant lymphoproliferative disorder (PTLD). Quantitative oropharyngeal EBV shedding measured by a DNA-DNA dot blot assay and the genotype of isolates determined by a polymerase chain reaction assay were studied in 23 renal and 23 cardiac transplant recipients followed over the first posttransplant year. Five patients developed PTLD and two additional PTLD renal transplant recipients were studied from the time of diagnosis. Significantly higher levels of EBV were observed in primary versus reactivation infection (P < .04) when sequential courses of antilymphocyte globulins or > 4 g of methylprednisolone were used in the first 6 months after transplant and in patients with versus those without PTLD (P < .04), although the former group had a high incidence of primary infection. Patients with the highest EBV shedding had the poorest serologic responses. All PTLD patients shed EBV-1, which was also shed by patients without PTLD.

Adolescent↗