Search PubMed⌕ Search

Biomedical subjects

M Brown

Publications and source records attributed to M Brown.

At least 1,027 records · Page 57Linked to original sources
PubMedDate not supplied

Pitch change in male-to-female transsexuals: has phonosurgery a role to play?

Male-to-female transsexuals, who have undergone gender reassignment surgery, may continue to have low pitched voices. Voice therapy may assist them to use their voice in a manner more likely to be perceived as female but, if this approach is unsuccessful, a laryngeal framework operation may be necessary to raise vocal pitch. This study assessed the effects of crico-thyroid approximation surgery in 14 transsexuals. Modal pitch was significantly increased by surgery but with substantial variation across speakers. Modal pitch was significantly correlated with judgements of gender by speech and language therapists who listened to tapes of the subjects. The results suggest that crico-thyroid approximation may be used to raise the pitch of voices of male-to-female transsexuals. Further research is needed to clarify the reasons for the variability in outcome, to monitor the longer-term changes in voice and the impact for clients of their modified voice in real life situations.

Adult↗
PubMedDate not supplied

Renal tubular peptide catabolism in chronic vascular rejection.

Chronic vascular rejection (CR) is the commonest cause of renal transplant loss, with few clues to etiology, but proteinuria is a common feature. In diseased native kidneys, proteinuria and progression to failure are linked. We proposed a pathogenic role for this excess protein at a tubular level in kidney diseases of dissimilar origin. We demonstrated in both nephrotic patients with normal function and in those with failing kidneys increased renal tubular catabolism and turnover rates of a peptide marker, Aprotinin (Apr), linked to increased ammonia excretion and tubular injury. These potentially injurious processes were suppressed by reducing proteinuria with Lisinopril. Do similar mechanisms of renal injury and such a linkage also occur in proteinuric transplanted patients with CR, and if so, is Lisinopril then of beneficial value? We now examine these aspects in 11 patients with moderate/severe renal impairment (51CrEDTA clearance 26.2+/-3.3 mL/min/1.73 m2), proteinuria (6.1+/-1.5 g/24 h) and biopsy proven CR. Lisinopril (10-40 mg) was given daily for 2 months in 7 patients. Four others were given oral sodium bicarbonate (Na HCO3) for 2 months before adding Lisinopril. Renal tubular catabolism of intravenous 99mTc-Apr (Apr* 0.5 mg, 80MBq), was measured before and after Lisinopril by gamma-ray renal imaging and urinary radioactivity of the free radiolabel over 26 h. Fractional degradation was calculated from these data. Total 24 h urinary N-acetyl-beta-glucoaminidase (NAG) and ammonia excretion in fresh timed urine collections were also measured every two weeks from two months before treatment. After Lisinopril proteinuria fell significantly (from 7.8+/-2.2 to 3.4+/-1.9 g/24 h, p<0.05). This was associated with a reduction in metabolism of Apr* over 26 h (from 0.5+/-0.05 to 0.3+/-0.005% dose/h, p < 0.02), and in fractional degradation (from 0.04+/-0.009 to 0.02+/-0.005/h, p<0.01). Urinary ammonia fell, but surprisingly not significantly and this was explained by the increased clinical acidosis after Lisinopril, (plasma bicarbonate fell from 19.1+/-0.7 to 17.4+/-0.8 mmol/L, p < 0.01), an original observation. Total urinary NAG did fall significantly from a median of 2108 (range 1044-3816) to 1008 (76-2147) micromol/L, p < 0.05. There was no significant change in blood pressure or in measurements of glomerular hemodynamics. In the 4 patients who were given Na HCO3 before adding Lisinopril, both acidosis (and hyperkalemia) were reversed and neither recurred after adding Lisinopril. These observations in proteinuric transplanted patients after Lisinopril treatment have not been previously described.

Adult↗
PubMedDate not supplied

Effect of pulsatility and hemodynamic power on recovery of renal function.

Circulatory assist devices are used to treat patients awaiting cardiac transplantation to preserve life as well as to permit recovery of end-organ function. The efficacy of pulseless perfusion versus pulsatile perfusion in the recovery of end-organ function has not been fully determined. In this study, the efficacy of pulseless perfusion compared to pulsatile perfusion on the recovery of renal function after a 30 min period of normothermic ischemia was examined. Pigs were randomly assigned to four groups. In all groups, acute renal ischemia was induced by clamping both renal arteries for 30 min. Reperfusion for 120 min was performed using either pulsatile perfusion or pulseless perfusion at 65 +/- 1.6 mm Hg (Groups I [pulsatile] and II [pulseless]) and at 40 +/- 1.1 mm Hg (Groups III [pulsatile] and IV [pulseless]). After reperfusion, renal blood flow, hemodynamic power (pressure * flow: hemodynamic power), oxygen consumption (VO2), tissue ATP, and urine output (UO) in Groups I, II, and III were significantly higher than in Group IV (p < .01 by ANOVA). Histopathologic examinations were not significantly different between groups. Under hypotensive conditions, pulsatile perfusion improves hemodynamic power delivery to the organ compared to pulseless perfusion. These results suggest that a pulseless pump is acceptable as an assist device when normal flow or perfusion pressure is maintained.

Animals↗
PubMedDate not supplied

Dimethylsulfoxide with heparin in the treatment of smoke inhalation injury.

Recent studies suggest that lung lesions occurring in inhalation injury result from actions of oxygen-free radicals released from polymorphonuclear leukocytes marginating in the pulmonary microcirculation and tracheobronchial region. Peroxide and hydroxyl ions have been implicated as mediators in the increased microvascular permeability and pulmonary edema noted after inhalation injury. In this study we evaluated the use of an O2-free radical scavenger, dimethylsulfoxide (DMSO), and heparin in the treatment of smoke inhalation. Ewes (N = 26) that had been surgically prepared five days earlier were insufflated with smoke from burning cotton. There were four groups: controls (n = 7), DMSO (n = 6), heparin (n = 6), and DMSO plus heparin (n = 7). All animals were given ventilatory support to maintain their PO2 above 60 mmHg and their PCO2 below 45 mmHg. There was a significant difference in survival rates between groups. By 72 hours all seven of the control group were dead. All animals in the DMSO plus heparin group survived, four of the DMSO group died, and two of the heparin group died. Lung lymph flow was not as high in the DMSO plus heparin group as in the heparin-only group. DMSO was proved effective in reducing the lung injury associated with smoke inhalation.

Animals↗
PubMedDate not supplied

Experience with silastic gel sheeting in pediatric scarring.

Silicone gel sheeting was applied to five hypertrophic scars on five pediatric outpatients at an acute care pediatric hospital. After silicone gel application, three of the five scars showed initial positive results including reduction in the scar size, reduction in the scar thickness, softening of the scar, a decrease in vascularity of the scar, and more uniform pigmentation. Many negative results including rash, skin breakdown, cessation of scar responsiveness, problems with the gel sheet application, and poor durability were documented. Preliminary results indicate that topical silicone gel application is not a viable treatment option for the control of hypertrophic scarring with a pediatric population.

Administration, Topical↗
PubMedDate not supplied

CNS mycosis fungoides: CT and MR findings.

Mycosis fungoides (MF) is a malignant T-cell lymphoma that primarily involves the skin, but may, in its advanced stages, metastasize to internal organs. From autopsy series, CNS involvement of MF can be seen in 14% of patients. We describe the CT and MR findings in three patients with CNS metastases. The images showed various manifestations of CNS MF, including parenchymal homogeneously intensely enhancing masses and ependymal enhancement. The CSF and biopsy results were eventually diagnostic in all three cases. One patient was treated prior to pathologic diagnosis, the other two were treated after diagnosis. The tumor improved following treatment in two patients. Although the imaging findings of CNS MF are nonspecific, they can be the first evidence of the disease.

Brain Neoplasms↗
PubMedDate not supplied

Injury- and use-related plasticity in adult auditory cortex.

After restricted cochlear lesions in adult animals the frequency selectivity of neurons in the cortical region deprived of its normal input by the lesion is changed such that the region is occupied by expanded representations of adjacent (perilesion) frequencies. These changes reflect a dynamic process of reorganization (plasticity) and are not explicable as passive consequences of the lesion. Analogous plasticity of cortical frequency selectivity and organization is seen following behavioural training that enhances the significance of particular acoustic stimuli. The occurrence of injury- and use-related auditory cortical plasticity gives rise to a number of questions relating to the mechanisms involved, the perceptual consequences and functional significance of such plastic changes, and their implications for the central processing of input from prosthetic devices. Evidence relating to these issues is briefly summarized in this review, and the directions of future research are considered.

Auditory Cortex↗
PubMedDate not supplied

Verbal and visual memory improve after choline supplementation in long-term total parenteral nutrition: a pilot study.

BACKGROUND: Previous investigations have demonstrated that choline deficiency, manifested in low plasma-free choline concentration and hepatic injury, may develop in patients who require long-term total parenteral nutrition (TPN). Preliminary studies have suggested lecithin or choline supplementation might lead to improved visual memory in the elderly and reverse abnormal neuropsychological development in children. We sought to determine if choline-supplemented TPN would lead to improvement in neuropsychological test scores in a group of adult, choline-deficient outpatients receiving TPN. METHODS: Eleven subjects (8 males, 3 females) who received nightly TPN for more than 80% of their nutritional needs for at least 12 weeks before entry in the study were enrolled. Exclusion criteria included active drug abuse, mental retardation, cerebral vascular accident, head trauma, hemodialysis or peritoneal dialysis, (prothrombin time [PT] >2x control), or acquired immune deficiency syndrome (AIDS). Patients were randomly assigned to receive their usual TPN regimen (n = 6, aged 34.0 +/- 12.6 years) over a 12-hour nightly infusion or their usual TPN regimen plus choline chloride (2 g) (n = 5, aged 37.3 +/- 7.3 years). The following neuropsychological tests were administered at baseline and after 24 weeks of choline supplementation (or placebo): Weschler Adult Intelligence Scale-Revised (WAIS-R, intellectual functioning), Weschler Memory Scale-Revised (WMS-R, two subtests, verbal and visual memory), Rey-Osterrieth Complex Figure Test (visuospatial functioning and perceptual organization), Controlled Oral Word Association Test (verbal fluency), Grooved Pegboard (manual dexterity and motor speed), California Verbal Learning Test (CVLT, rote verbal learning ability), and Trail Making Parts A & B (visual scanning, psychomotor speed and set shifting). Scores were reported in terms of standard scores including z scores and percentile ranks. Mean absolute changes in raw scores were compared between groups using the Wilcoxon rank sum test, where p values < .05 constituted statistical significance. RESULTS: Significant improvements were found in the delayed visual recall of the WMS-R (7.0 +/- 2.7 vs -.33 +/- 5.7, p = .028), and borderline improvements in the List B subset of the CVLT (1.0 +/- 0.8 vs -2.0 +/- 2.4, p = .06) and the Trails A test (-3.8 +/- 8.1 vs 3.7 +/- 4.5 seconds, p = .067). No other statistically significant changes were seen. CONCLUSIONS: This pilot study indicates both verbal and visual memory may be impaired in patients who require long-term TPN and both may be improved with choline supplementation.

Adult↗
PubMedDate not supplied

The effects of electrical stimulation on the quadriceps during postoperative knee immobilization.

Immobilization of the knee after anterior cruciate ligament (ACL) reconstruction results in marked thigh atrophy and decrease in quadriceps strength that may prolong the rehabilitation program of the injured athlete. Fifteen male volunteers undergoing ACL reconstruction were divided into two groups, stimulation (during immobilization) and nonstimulation. Measurements of thigh circumference and isometric quadriceps strength were tested preoperatively, immediately after cessation of cast immobilization (6 weeks), and at 9 and 12 weeks postoperatively. The changes in circumference and strength between the first preoperative test and all subsequent tests were compared for statistical significance (Student's t-test, P less than 0.5) between the two groups. The decrease in quadriceps strength of the stimulation group during immobilization was significantly less than that of the nonstimulation group, although later differences between the two groups were not significant. There were no significant differences in thigh atrophy between the two groups. In conclusion, isometric quadriceps torque decreases resulting from immobilization can be significantly lessened by application of electrical stimulation during immobilization. Electrical stimulation to the quadriceps does not significantly alter thigh circumference changes that occur during immobilization.

Adolescent↗
PubMedDate not supplied

Improving patient care and quality of life after laryngectomy/glossectomy.

Patients undergoing total laryngectomy/glossectomy are left without a voice at least temporarily in the early postoperative stage, since their larynx and/or tongue has been removed. Those patients rendered permanently speechless usually acquire a form of mechanical speech through electronic devices. However, the life-changing nature of this surgery should not be underrated as effectively these people have lost their normal voice. It can be argued that this patient group is also without a voice in a political sense - theirs seems to be a forgotten cancer, as other forms of cancer appear to attract greater attention for research priorities and funding. In some ways this research attempts to redress the balance through exploring the patient experience postoperatively, in particular the issues related to communication for this patient group. The results also highlight the emotional trauma experienced by patients and the mechanisms healthcare staff employ to support these patients. This research is multidisciplinary, involving patients and all those health workers that come into contact with them on the ward. The patient experience forms a major part of this article, allowing their stories to form much of the content. The results draw attention to deficiencies in service delivery that, as a direct result of this research, have been and are being addressed so that patients' care is improved and their quality of life is restored. Such change has been driven by patient comment such as: 'But then when you wake up after that operation that's the pits when you are laying there and you think "I'm dead". And then when you wake up properly that's the bit I always say you wish you were dead. That's when you wish you had died.'

Attitude to Health↗
PubMedDate not supplied

[Inhaled corticosteroids and growth - a review]

OBJECTIVE: The aim of this review was to evaluate the medical literature in the last 10 years regarding the impact of the use of ICS on children and adolescents growth.METHODS: literature review.RESULTS: The use of ICS in childhood asthma in dosages appropriate to its severity does not seem to impair the adult height.CONCLUSIONS: The use of ICS in childhood asthma does not seem to impair growth. However, it is prudent to use the lowest possible dose necessary to achieve a good clinical control of asthma, as well as to monitor the growth of any child/adolescent receiving ICS.

Journal Article↗
PubMedDate not supplied

Medical equipment inventory and service scheduling by computer: experience with a working scheme.

In Liverpool Health Authority a computer inventory of over 6000 items of medical equipment is used as an aid to servicing and management. Extracts from the inventory are used to guide work in several different servicing units and the cross-referencing facility is employed to provide lists of equipment by category (for example, manufacturer, hospital, department, cost band, age etc.). After four years' experience of this scheme we conclude that the costs are justified by the benefits to the equipment servicing programmes and to the management of equipment. However, the information made available for other purposes within the health authority (administration, supplies, finance etc.) has not been made use of to the extent that the whole cost could be justified as a management service. We have also found that the quality of inventory records and usage are improved where technicians can use the computer directly, and we find that medical physics technicians quickly come to understand such systems thereby minimizing support costs.

Computers↗
PubMedDate not supplied

Nothing to declare.

Explore the source record for details and available documents.

Character↗