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Biomedical subjects

D Meyer

Publications and source records attributed to D Meyer.

At least 613 records · Page 34Linked to original sources
PubMedDate not supplied

Secondary sexual development of Cape coloured boys following kwashiorkor.

This report describes the secondary sexual development of 78 Cape Coloured male ex-kwashiorkor patients and 53 male controls. All patients were originally seen between 5 months and 4 years 4 months of age, treated and then followed up for 15 years after discharge. Age at peak height velocity (PHV) was available for 23 ex-patients and 15 controls. Maximum likelihood estimates of the mean age at entry to each pubertal stage were made and age at PHV was obtained by fitting a non-linear growth function to the data for each subject with appropriate serial height records. No significant differences were observed between ex-patients and controls for either the sequence of pubertal events or for the age of entry to each stage. When compared to a sample of normal British boys the Cape Coloured sample exhibited significant delay for ages at entry to all pubertal stages with differences ranging from 0.84 years for PH2 to 1.94 years for PH5. It is suggested that adrenal androgens play a major role in delaying secondary sexual development during chronic malnutrition and that the anterior pituitary's response to such conditions is to selectively delay pubertal status.

Adolescent↗
PubMedDate not supplied

Clinicopathologic correlation of argon-laser photocoagulation of an idiopathic choroidal neovascular membrane in the macula.

The clinicopathologic features of an idiopathic choroidal neovascular membrane treated by argon laser photocoagulation are presented. The area of treatment is characterized microscopically by a proliferation of fibrocytes and retinal pigment epithelial cells. No choroidal vascular membrane was identified. Capillaries were present in the scar but not internal to the level of Bruch's membrane.

Choroid↗
PubMedDate not supplied

Pulsed carbon dioxide laser for cartilage vaporization and subchondral bone perforation in horses. Part I: Technique and clinical results.

A carbon dioxide laser, used in a rapidly pulsed mode, was evaluated for intra-articular use in horses. Under arthroscopic guidance, a lensed 5 mm laser probe attached directly to a hand-held carbon dioxide laser was inserted into one intercarpal joint of eight horses. In four horses, a cartilage crater 1 cm in diameter was created to the level of the subchondral bone of the articular surface of the third carpal bone. In four horses, the laser was directed perpendicular to the articular surface of the third carpal bone and activated to penetrate the cartilage and subchondral bone. The intercarpal joint of the opposite carpus in each horse was subjected to arthroscopic examination and insertion of the laser probe for an equivalent time. The laser was not activated and these joints served as sham operated controls. The horses were evaluated clinically for 8 weeks, then euthanatized, and the joints were examined radiographically, grossly, and histologically. Pulsed carbon dioxide laser vaporized cartilage readily but penetrated bone poorly. Cartilage vaporization resulted in no greater swelling, heat, pain on flexion, lameness, or synovial fluid reaction than the sham procedure. Laser drilling resulted in a shallow, charred hole with a tenacious carbon residue, and in combination with the thermal damage to deeper bone, resulted in increased swelling, mild lameness and a low-grade, but persistent synovitis. The carbon dioxide laser is a useful intra-articular instrument for removal of cartilage and has potential application in inaccessible regions of diarthrodial joints. It does not penetrate bone sufficiently to have application in subchondral drilling.

Animals↗
PubMedDate not supplied

Differential distribution of von Willebrand factor in endothelial cells. Comparison between normal pigs and pigs with von Willebrand disease.

Endothelial cells were cultured from the thoracic aorta, inferior vena cava, and pulmonary artery of normal adult and young pigs as well as from pigs with von Willebrand disease (vWD). The von Willebrand factor (vWF) was estimated by ELISA in endothelial cell supernatants and lysates as well as by immunofluorescence of cells by use of either a polyclonal or a monoclonal antibody to vWF. In normal adult pigs, the content of vWF in supernatants and cell lysates was the highest in the pulmonary artery, lower in the inferior vena cava, and almost nil in the thoracic aorta. In the normal young pigs, vWF was higher in the inferior vena cava endothelial cell supernatants and lysates than in the pulmonary artery. Thus the synthesis of vWF by endothelial cells varies along the vascular tree and appears to be modulated by the age of the animals. In pigs with vWD, levels of vWF were slightly detectable in endothelial cells from the pulmonary artery (contrasting with levels of plasmatic vWF below 0.01 U/ml), but were undetectable in the thoracic aorta and inferior vena cava. Thus, if vWF plays a role in atherogenesis, this involves circulating, not its intracellular, form.

Aging↗
PubMedDate not supplied

Chemotherapy for extraocular retinoblastoma.

Because few patients with extraocular retinoblastoma are seen in the United States and Europe, it has been difficult to establish the optimal role of chemotherapy in such cases. We examined the efficacy of two chemotherapy combinations (cisplatin/etoposide and cyclophosphamide/doxorubicin) in patients with extraretinal retinoblastoma, administered prior to radiotherapy in four patients with recurrent or advanced primary disease. Responses were evaluable in three patients, each of whom was treated by both chemotherapy regimens and radiotherapy. Multimodality therapy promises to be of benefit to patients with extraocular retinoblastoma, and future studies will explore alternative chemotherapy combinations for this purpose.

Antineoplastic Combined Chemotherapy Protocols↗
PubMedDate not supplied

Outcome for patients with constitutional 13q chromosomal abnormalities and retinoblastoma.

The outcomes for five patients with retinoblastoma and constitutional chromosomal abnormalities involving the long arm of chromosome 13 are reported. All patients demonstrated developmental delay and mental retardation. Four of these patients are alive 23, 21, 15, and 1 year from diagnosis; one died of pneumonia with septicemia. Each of the four survivors has, with aging, shown hypotonia, mutism, contractures, and inability to function independently.

Abnormalities, Multiple↗
PubMedDate not supplied

Progress in experimental intestinal transplantation in small animal models.

The unique immune response after small bowel transplantation (SBT) has been the subject of extensive research using small animal models in rats and mice. These animals are inexpensive, for most societies ethically acceptable and the existence of inbred strains allows for reproducibility and defined immunobiological conditions. The basic immunological reactions, such as graft-versus-host-reactions (GVHR), host-versus-graft-reactions (HVGR), a combination of both reactions, chronic rejection and tolerance have been described. Almost all immunosuppressive agents of proven or potential clinical relevance have been tested for their efficacy in small bowel transplantation. All techniques which are applied to intestinal transplantation in humans including multiorgan transplantation, can also be performed in rats. Intestinal transplantation in mice is methodically restricted to heterotopic transplantation. The mouse however, offers several advantages compared to the rat model. A large number of congenic and knockout strains is available as well as many analytical tools. In the future, intriguing new insights into the unique immunological mechanisms of allograft rejection will be discovered using murine models.

Animals↗
PubMedDate not supplied

Cost-effectiveness of strategies to enhance mammography use.

OBJECTIVE: To estimate the cost-effectiveness of three strategies to increase breast cancer screening with mammography (reminder postcard, reminder telephone call, and motivational telephone call). DESIGN: Cost accounting for each strategy followed by cost-effectiveness analysis. DATA SOURCE FOR EFFECTIVENESS: Randomized trial of three strategies conducted at Group Health Cooperative of Puget Sound (GHC). TARGET POPULATION: Women 50 to 79 years of age who were enrolled in GHC's breast cancer screening program who did not schedule screening mammography within 2 months after it was recommended by letter. PERSPECTIVE: Health plan. OUTCOME MEASURE: Marginal cost-effectiveness of each additional woman screened. RESULTS OF BASE-CASE ANALYSIS: Because of its high cost (about $26 per call) and intermediate effectiveness, the motivational call was the least cost-effective strategy. If it was assumed that 50% of the women who scheduled mammography after receiving the reminder postcard would have scheduled mammography within 10 months even without it, marginal cost-effectiveness for the postcard among all women was $22 per woman screened versus $92 for the reminder call. Among women with no previous mammography, the marginal cost-effectiveness for the postcard was $70 versus $100 for the reminder call. RESULTS OF SENSITIVITY ANALYSIS: Among women with no previous mammography, the choice between the reminder postcard and the reminder call was sensitive to assumptions about the percentage of women expected to receive mammography in the absence of other promotional strategies. CONCLUSIONS: A simple reminder postcard is the most cost-effective way to increase mammography. Choices about how to promote mammography will ultimately depend on plan values and willingness to invest in promotional strategies that increase participation at higher unit costs.

Aged↗
PubMedDate not supplied

Abnormal serum lipoprotein levels as a risk factor for the development of human lenticular opacities.

AIM: To determine whether an association exists between the different plasma lipoprotein constituents and the prevalence of lenticular opacities in dyslipidaemic subjects. METHODS: Adult patients (n = 115) of both genders were included if their fasting total serum cholesterol concentrations exceeded the 95th percentile of normal or their serum low-density lipoprotein (LDL): high-density lipoprotein (HDL) ratios exceeded 5. Patients were excluded if they suffered from any condition known to cause, or predispose them to, elevated lipoprotein levels or lenticular opacification. Lenticular changes were assessed by means of a slit-lamp through the fully dilated pupil. RESULTS: An extremely strong association (p<0.0001) was found to exist between HDL cholesterol levels and the development of lens opacities. Below an HDL-C level of 1.5 mmol/l subjects had a seven-fold higher calculated probability of falling in the lens opacity subgroup than those with HDL-C levels above 1.5 mmol/l [odds ratio =7.33 (95% CI = 2.06-26.10; p = 0.0001)]. An equally strong association was found between high (>5) LDL:HDL ratios and the development of lens opacities (p<0.0003). The risk of falling into the cataract subgroup if the individual's LDL:HDL ratio exceeded 5 was 2.35 (95% CI = 1.09-5.04; p = 0.014). CONCLUSION: This study strongly suggests that an association exists between low levels of HDL cholesterol and high LDL:HDL ratios on one hand and the development of adult lens opacification on the other.

Adolescent↗
PubMedDate not supplied

Serum lipid parameters and the prevalence of corneal arcus in a dyslipidaemic patient population.

AIM: To determine whether an association exists between plasma lipoprotein constituents and the prevalence of corneal arcus in dyslipidaemic patients. METHODS: Adult patients (n = 115) were included if their fasting total serum cholesterol concentrations exceeded the 95th percentile or their serum low-density lipoprotein (LDL) : high density lipoprotein (HDL) ratios exceeded 5. Slit-lamp assessment of the corneas was performed. RESULTS: The study group divided into a subgroup with arcus 37% (43) and a subgroup without arcus 63% (72). Total serum cholesterol and triglyceride levels were not associated with corneal arcus. A significant difference was found (p < 0.05) between the mean levels of LDL cholesterol (LDL-C) in the group without arcus (5.61 +/- 1.74 mmol/l) and the group with arcus (5.96 +/- 1.71 mmol/l). The mean serum HDL-cholesterol (HDL-C) in the group with corneal arcus was 1.04 +/- 0.30 mmol/l as opposed to 1.31 +/- 0.38 mmol/l in the group without arcus (p < 0.005 for difference). The mean LDL-C : HDL-C ratio in the group without arcus was 4.28 (SD: 1.99), and 5.73 (SD: 2.09) in the group with a corneal arcus (p < 0.05). CONCLUSIONS: Low HDL-C levels, high LDL-C levels and LDL-C : HDL-C ratios > 5 have been implicated as risk factors of numerous circulatory diseases. The observations in this study suggest that the presence of corneal arcus in the dyslipidaemic patient correlates strongly with these same risk indicators.

Adult↗
PubMedDate not supplied

Children's responses to nursing attire.

PURPOSE: To investigate how nursing attire affects children. METHOD: One hundred children ages 3, 4, and 5 years were interviewed. Fifty of the children had previously been hospitalized and 50 had no hospital experience. Five color photographs of a nurse representing five different uniform styles were shown to each child. The children were asked to select a photograph in response to questions. RESULTS: Fifty-eight percent of the children preferred the smock top. The traditional white uniform was considered frightening by 41% of the children. Chi Square analysis finds the differences in selection of uniforms to be significant at the .001 level. CONCLUSIONS: The children preferred and were least frightened by the colorful smock top uniform style. The least preferred and most frightful attire was the traditional dress uniform.

Child, Preschool↗