Search PubMed⌕ Search

Biomedical subjects

M Winter

Publications and source records attributed to M Winter.

At least 91 records · Page 5Linked to original sources
PubMed1996

Incidence and spectrum of renal abnormalities in Williams-Beuren syndrome.

Kidneys and urinary tract were examined systematically by ultrasonography in 130 patients with Williams-Beuren syndrome (59 females, median age 5.5 years; 71 males, median age 6.4 years). In addition, serum creatinine was determined and an analysis was performed. Creatinine clearance was available in 79 patients. Renal angiographic examinations were done in 18 patients, 8 of whom had renal artery narrowing (44%). The incidence of renal anomalies in Williams-Beuren syndrome was 17.7% vs. around 1.5% in the normal population (P < 0.0003). The spectrum of these anomalies ranged from minor anomalies such as bladder diverticula to more severe malformations such as renal aplasia or hypoplasia (in 5 of 130 patients). In nine patients a duplicated kidney was found. A decreased creatinine clearance (two patients), recurrent symptomatic urinary tract infections (four patients), and hypertension were uncommon. Nephrocalcinosis was not found in our patients. Our data demonstrate that the risk of a structural abnormality of the kidneys and the urinary tract is increased 12- to 36-fold in Williams-Beuren syndrome compared to the normal population. Ultrasound screening of the renal system should be part of the first evaluation of WBS patients.

Adolescent↗
PubMed1996

[Color Doppler ultrasound studies of benign and malignant lymph nodes].

Color-coded duplex sonography is being increasingly used in the head and neck as another method for diagnosis of such disorders as stenosis of arteries or veins or hemangiomas. A possible additional advantage of testing is the ability to differentiate benign from malignant tumors. Since the underlying cause of a suspicious lesion is most important for treatment strategies, we investigated histologically-proven benign and malignant cervical lymph nodes for determining the value of color-coded duplex sonography. In the present study, 135 patients (45 women and 90 men; ages 30-63 years) with palpable cervical lymph nodes were examined with both ultrasound and color-coded duplex sonography. Afterwards, lymph nodes were removed by open biopsies or neck dissections. The histological results were then compared to perfusion velocities and pulsation indices from the color-coded duplex sonography. However, no significant differences were found between the benign and malignant nodes. When comparing perfusion and color, each group was seen to be non-homogeneous and no typical distribution of vascularization was demonstrable. Findings showed that color-coded duplex sonography is currently not an accurate indicator of lymph node pathology.

Adult↗
PubMed1996

Collateral flow changes through the anterior communicating artery during carotid endarterectomy.

To evaluate early changes in collateral flow through the anterior communicating artery, 11 patients undergoing carotid endarterectomy were monitored. All had angiographically demonstrated collateral flow towards the hemisphere on the side of surgery. The middle cerebral artery ipsilateral to the operated side and the contralateral anterior cerebral artery were simultaneously insonated with a transcranial Doppler instrument equipped with dual transducers, and flow velocity values were obtained at specific surgical stages. Mean flow velocity in the contralateral anterior cerebral artery's A1 segment increased at clamp placement (p = 0.036), did not change during clamping, and decreased at clamp release (p = 0.004). The rise in velocity occurred within seconds of clamp placement in all patients with an increase, reaching the 10 cm/s threshold within 1 min. No consistent increase was detected after 5 min. A decrease in pulsatility index, indicating a drop in resistance, was detected at clamp placement in the middle cerebral artery on the side of surgery (p = 0.012). The index did not change during clamping, but increased at clamp release (p = 0.002). Our findings indicate that significant changes in anterior communicating artery collateral flow occur during carotid endarterectomy, starting within seconds of carotid artery clamping. These changes are associated with arterial resistance alterations in the territory of the middle cerebral artery on the endarterectomy side. Our observations should be useful to assess intracranial early collateral flow changes in surgical and non-surgical settings.

Aged↗
PubMed1996

Increased numbers of primed activated CD8+CD38+CD45RO+ T cells predict the decline of CD4+ T cells in HIV-1-infected patients.

OBJECTIVE: To look for surrogate markers in HIV-1 infection that can predict the decline of CD4+ T cells. METHODS: Multiparameter flow cytometric analyses of CD8+ lymphocytes were performed. These cells were investigated for their expression of the activation marker CD38+ within the naive (CD45RA+) and primed (CD45RO+) subsets. Serial CD4 counts were plotted for each patient and the straight line that best fitted was obtained using least squares regression. Differences in rate of decline were tested using analysis of variance, after each patient was weighted by the reciprocal of the variance. RESULTS: Baseline levels of percentages of CD8+CD38+ T lymphocytes predict the CD4 decline in HIV-1-infected patients. Within the CD8+ subset, the primed CD8+CD38+CD45RO+ population was responsible for this prediction. Conversely, the naive CD8+CD38+CD45RA+ population was not predictive. Patients who initially showed a percentage of CD8+CD38+ T lymphocytes above the median (> 25%) had a more marked decline in CD4+ T cells when compared to individuals with percentages of CD8+CD38+ T lymphocytes below the median value (79.3 and 21.2 x 10(6)/l mean CD4 cell decline per year, respectively). Similarly, percentages of CD8+CD38+CD45RO+ T cells above the median value (> 7%) were also associated with a more rapid decline (69.4 and 14.2 x 10(6)/l mean CD4+ cell decline per year). These results were statistically significant after adjustment for the baseline CD4 count and beta 2-microglobulin levels. CONCLUSIONS: Percentages of activated CD8+ cells expressing CD38+ can predict the rate of decline (slope) of the CD4+ T cells. This resides in the CD45RO+ primed population. An early prediction of the CD4+ slope will allow the clinician to target treatment to those patients that are most likely to benefit.

ADP-ribosyl Cyclase↗
PubMed1996

The spectrum of ocular features in the Williams-Beuren syndrome.

One hundred and fifty-two patients with the Williams-Beuren syndrome were examined to assess the frequency and severity of ophthalmological features associated with the disorder. Eighty-two (54%) had strabismus, all but three, esotropia. One hundred and seventeen (77%) patients had blue irides, 10 (7%) green, and 25 (16%) brown. One hundred and twelve (74%) showed a typical so-called stellate iris pattern of the anterior stroma. Whitish anomalies were also detectable in brown irides. Two 9-year-old patients and one 46-year-old patient had initial cataract. Of all the patients with funduscopy, 22% had retinal vascular tortuosity. One patient had suspected Rieger syndrome. Two patients had ptosis, one with a Marcus-Gunn phenomenon. No ocular manifestation of hypercalcaemia was noted.

Adolescent↗
PubMed1996

Effect of time and cerebrovascular symptoms of the prevalence of microembolic signals in patients with cervical carotid stenosis.

BACKGROUND AND PURPOSE: High-intensity transient signals (HITS) detect ed by transcranial Doppler ultrasonography correspond to microemboli in intracranial arteries. The aim of this study was to determine the time course of cerebral microembolism in patients with symptomatic internal carotid artery stenosis and to assess its relation to specific symptoms of cerebral ischemia. METHODS: On the basis of criteria established a priori, 69 middle cerebral arteries were selected from a series of consecutive studies obtained at our neurovascular laboratory. All patients had radiological evidence of cervical internal carotid artery disease and had corresponding symptoms. A TC-2000 instrument equipped with special software for microembolus detection was used. Accepted signals were unidirectional from baseline, had a chirping sound, were 9 dB higher than the surrounding blood, and lasted 25 milliseconds or more. RESULTS: HITS were identified in 20 of 69 (29%) arteries. The median interval between onset of symptoms and time of testing was 4 days for HITS-positive arteries and 12 days for those that were HITS negative (P=.0046). Fourteen of 32 (44%) arteries with transient ischemic attacks and 6 of 37 (16%) arteries with cerebral infarction were HITS positive (P=.012). CONCLUSIONS: In patients with symptomatic carotid stenosis, HITS are detected more frequently when patients are tested soon after symptoms of cerebral ischemia. HITS are also more prevalent in the territories of arteries with transient ischemic attacks rather than cerebral infarction. These findings may have diagnostic and therapeutic implications.

Adult↗
PubMed1996

Analysis of consecutively placed loaded root-form and plate-form implants in adult Macaca mulatta monkeys.

The present paper describes 36 consecutively treated non-human primates (Macaca mulatta) as part of a balanced block design study to examine osseointegration in root- and plate-form implants prepared by atraumatic preparation of bone. Clinical measurements around selected teeth and digital radiology were utilized to monitor periodontal disease and bone loss around root- and plate-form implants which were loaded with a fixed prosthesis. Results indicate that once monthly regimen of scaling and root planing can prevent attachment loss in natural teeth, serving as abutments of loaded bridges. Root-form implants exhibited a significant loss of crestal bone height during the first year (P < 0.03) while plate-form implants showed less loss in bone height. There was an increase in bone mass over time for root-form or plate-form implants. Both root-form and plate-form implants provided radiographic evidence of osseointegration in loaded bridges.

Alveolar Bone Loss↗
PubMed1996

Reducing alcohol-impaired driving in Massachusetts: the Saving Lives Program.

OBJECTIVES: The purpose of this study ws to assess whether a community program begun in March 1988 that organized multiple city departments and private citizens could reduce alcohol-impaired driving, related driving risks, and traffic deaths and injuries. METHODS: Trends in fatal crashes and injuries per 100 crashes were compared in Saving Lives Program cities and the rest of Massachusetts from March 1984 through February 1993. In annual roadside surveys conducted at randomly selected locations, safety belt use among occupants of 54577 vehicles and travel speeds of 118442 vehicles were observed. Four statewide telephone surveys (n = 15188) monitored self-reported driving after drinking. RESULTS: In program cities relative to the rest of Massachusetts during the 5 program years in comparison with the previous 5 years, fatal crashes declined 25%, from 178 to 120, and fatal crashes involving alcohol decreased 42%, from 69 to 36. Visible injuries per 100 crashes declined 5%, from 21.1 to 16.6. The proportions of vehicles observed speeding and teenagers who drove after drinking were cut in half. CONCLUSIONS: Interventions organized by multiple city departments and private citizens can reduce driving after drinking, related driving risks, and traffic deaths and injuries.

Accidents, Traffic↗
PubMed1996

Lowering state legal blood alcohol limits to 0.08%: the effect on fatal motor vehicle crashes.

OBJECTIVES: This study was undertaken to determine whether reductions in alcohol-related fatal crashes following adoption of 0.08% legal blood alcohol limits were independent of general regional trends. METHODS: The first five states that lowered legal blood alcohol limits to 0.08% were paired with five nearby states that retained a 0.10% legal standard. Within each pair, comparisons were made for the maximum equal available number of pre- and postlaw years. RESULTS: States adopting 0.08% laws experienced 16% and 18% relative postlaw declines in the proportions of fatal crashes involving fatally injured drivers whose blood alcohol levels were 0.08% or higher and 0.15% or higher. CONCLUSIONS: It all states adopted 0.08% legal blood alcohol limits, at least 500 to 600 fewer fatal crashes would occur annually.

Accidents, Traffic↗
PubMed1996

Promoting weight loss in type II diabetes.

OBJECTIVE: To examine strategies-behavioral therapies, exercise, diet, anorectic drugs, surgery, or a combination of strategies-used for promoting weight loss in people with type II diabetes. RESEARCH DESIGN AND METHODS: Meta-analysis was used to synthesize research of promoting weight loss in the population. Literature search strategies involved reviewing bibliographies, conducting computer searches and surveys of relevant master's degree programs, and contacting representatives of the Centers for Disease Control. The final sample consisted of 89 studies involving 1,800 subjects. Data were extracted on 80 variables characterizing the sample of studies/subjects and on 23 outcome variables, including weight, metabolic control, lipids, and other physiological parameters. RESULTS: Diet alone had the largest statistically significant impact on weight loss (-20 lb) and metabolic control (-2.7% in glycosylated hemoglobin). All diets significantly improved fasting blood sugar. Behavioral programs alone had a statistically significant impact on weight loss (-6.4 lb) and metabolic control (-1.5%) but effects were less than for diet alone. Data from the few exercise studies indicated that weighted average effects for exercise on weight loss (-3.4 lb) and metabolic control (-0.8%) were less than diet alone. Behavioral therapy plus diet plus exercise was associated with statistically significant effect size estimates for weight loss (-8.5 lb) and metabolic control (-1.6%). Diet alone achieved better results. Effects of weight promotion strategies, in general, were smaller in experimental studies and for individuals over age 55. CONCLUSIONS: Dietary strategies are most effective for promoting short-term weight loss in type II diabetes. A number of gaps exist in the extant literature- descriptions of subjects, interventions, or longitudinal outcomes beyond 12 months after intervention.

Blood Pressure↗
PubMed1995

Cerebral microembolism during carotid endarterectomy.

BACKGROUND: This study was designed to assess the intraoperative risk of cerebral microembolism, as detected by transcranial Doppler ultrasonography, during carotid endarterectomy. PATIENTS AND METHODS: Thirty-six patients (37 procedures) with symptomatic (n = 35) or asymptomatic (n = 2) internal carotid artery origin stenosis(> 50%) were monitored continuously during carotid endarterectomy. Special instrumentation was used to detect high-intensity transient signals (HITS) in the middle cerebral artery on the carotid endarterectomy side. All HITS satisfied a priori established criteria. RESULTS: The incidence of carotid endarterectomies with formed-element HITS increased at clamp release (23/37, P < 0.001) and shunt opening (7/11, P = 0.014), and during wound closure (13/22, P< 0.005) and shunting (5/11, P = 0.046). HITS with air microbubble characteristics were detected at clamp release (22/37, P < 0.001) and shunt opening (5/11, P = 0.025). CONCLUSIONS: HITS do not occur randomly during carotid endarterectomy. Shunting, unclamping, and wound closure are high-risk periods.

Aged↗
PubMed1995

[Sandwich intraocular lens implant: a concept for aphakia correction in children].

BACKGROUND: In the management of congenital cataracts the correction of aphakia is still an unsatisfactorily solved problem. As far as surgical techniques and materials are concerned, the implantation of an IOL seems to be justified even in younger children; but choosing the refractive power of the lens is somewhat difficult regarding the expected growth of the eye. MATERIALS AND METHODS: A new type of IOL is presented as a solution for this problem. Being composed of a PMMA-fashioned optic and haptic it bears a silicone lens which is fastened on top of it. The supporting lens is made of PMMA (polymethylmethacrylate) with a biconvex surface with modified J-loops. The diameter of the optic is 6 mm, the overall diameter is 11 mm. The supplementary lens is made of the same silicone material as used for foldable intraocular lenses. Its diameter is 4.5 mm. This additional component can be removed from the implanted lens so that the needed reduction of refractive power after completed growth of the eye can be performed. The PMMA-fashioned basic component remains in situ just like a conventional posterior chamber lens. The lens was examined using scanning-electron microscopy. Im- and explantation was performed in isolated porcine eyes. RESULTS: The high quality of the lens could be demonstrated using scanning-electron microscopy. The technical feasibility of this concept could be demonstrated on isolated porcine eyes. DISCUSSION: Currently the sandwich lens is being tested in animal experiments. Our special interest is focussed on biocompatibility, formation of secondary cataract, biological reactions in the interface and the possibility of atraumatic explantation of the silicone lens.

Aphakia, Postcataract↗
PubMed1994

DNA repair capacity as a risk factor for non-melanocytic skin cancer--a molecular epidemiological study.

Capacity to repair UV-induced DNA damage was studied by use of host cell reactivation assay in T lymphocytes isolated from 86 cases and 87 controls (aged 44-68 years) who were participants in a population-based case-control study of basal cell (BCC) or squamous cell (SCC) carcinoma of the skin in Geraldton, Western Australia. Lymphocytes were cultured and transfected with either control or UV-irradiated plasmids (254 nm, 350 J/m2) containing a reporter gene [the chloramphenicol-acetyltransferase (CAT) gene], and the repair capacity was determined by measuring CAT gene expression in protein extracts prepared from the transfected cells. DNA repair activity was 1.07 (95% confidence interval 0.94-1.26) times greater in BCC cases than in controls for each 350 J/m2 increment in UV dose to the plasmids, and 1.04 (95% confidence interval 0.85-1.26) times greater in SCC cases than in controls, though the differences were not statistically significant. DNA repair activity showed little association with age, sex and viability of the lymphocytes, though it was positively associated with their blastogenic rate (p = 0.055).

Adult↗