PubMed Health⌕ Search

Biomedical subjects

A Myers

Publications and source records attributed to A Myers.

At least 19 recordsLinked to original sources
PubMed2001

Liposomal daunorubicin in the treatment of relapsed or refractory non-Hodgkin's lymphoma.

PURPOSE: To assess the efficacy and toxicity of liposomal daunorubicin administered as a two-hour intravenous infusion to patients with relapsed or refractory non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: Eligible patients had relapsed or refractory NHL with measurable or evaluable disease, and low grade, select intermediate grade, or mantle cell pathologic types. Prior exposure to an anthracycline or anthracenedione was allowed. Liposomal daunorubicin at a dose of 100 mg/m2 was given intravenously over a minimum of 120 minutes every 3 weeks. as a single agent. RESULTS: Thirty-three patients were accrued: twenty-three (70%) had low-grade histologies; six (18%) had intermediate-grade histologies (follicular large-cell and diffuse small cleaved); and four (12%) patients had mantle-cell lymphoma. Eighteen (55%) had received two or more prior regimens; fourteen (42%) received a prior anthracycline. A median of six cycles of liposomal daunorubicin were administered (range 1-15). Of 31 patients evaluable for response, 2 complete and 10 partial remissions were documented for a major response rate of 39% (95% confidence interval (CI): 22%-58%). The median duration of response was 19.5 months (range 4.3-41.1+). Six responders (50%) had received a prior anthracycline; one responder had mantle-cell histology. The major toxicities were grade 3 or 4 neutropenia in 26 patients (79%), mild to moderate nausea in 22 (67%), and fatigue in 16 (48%). CONCLUSIONS: Liposomal daunorubicin at 100 mg/m2 every three weeks has activity in patients with relapsed or refractory NHL, including patients with prior exposure to an anthracycline. Further studies of liposomal daunorubicin in combination with other agents are warranted.

Adult↗
PubMed2001

Genetic markers of male infertility: Y chromosome microdeletions and cystic fibrosis transmembrane conductance gene mutations.

Today, approximately 15% of couples have reduced fertility. In most cases the reason is male infertility, usually of genetic origin. Thus, in the context of research in genes involved in reproduction and sex determination, genetic defects in gametogenesis are being extensively studied. The most frequent pathogenic causes of male infertility are Y chromosomal microdeletions and obstructive azoospermia due to congenital absence of the vas deferens (CAVD) in the presence of mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. We have investigated the most common CFTR gene alterations in Croatian men with CAVD, using Roche research prototype assays. Results revealed that the 5T variant was present in 27% of the subjects. The F508 deletion was found in 21% of the subjects. It was the most frequent mutation, although its incidence was much lower than among patients with cystic fibrosis. The prevalence of microdeletions in the azoospermia factor region (AZF) of the Y chromosome in Croatia was 4.5%. This is the first report of Y microdeletions in the Croatian population. Genetic counseling of all couples with the diagnosis of male infertility is recommended before intrauterine insemination, in vitro fertilization, and intracytoplasmic sperm injection, and should also include AZF and CFTR genotyping. Couples requesting assisted reproductive treatment should be offered molecular analysis of the CFTR gene, if male infertility due to obstructive azoospermia is the underlying cause. Also, men with severe oligozoospermia or non-obstructive azoospermia seeking assisted reproductive treatment should be screened for deletions in the Y chromosome.

Chromosome Deletion↗
PubMed2000

Susceptibility locus for Alzheimer's disease on chromosome 10.

The apolipoprotein E (APOE) gene is the only genetic risk factor that has so far been linked to risk for late-onset Alzheimer's disease (LOAD). However, 50 percent of Alzheimer's disease cases do not carry an APOE4 allele, suggesting that other risk factors must exist. We performed a two-stage genome-wide screen in sibling pairs with LOAD to detect other susceptibility loci. Here we report evidence for an Alzheimer's disease locus on chromosome 10. Our stage one multipoint lod score (logarithm of the odds ratio for linkage/no linkage) of 2.48 (266 sibling pairs) increased to 3.83 in stage 2 (429 sibling pairs) close to D10S1225 (79 centimorgans). This locus modifies risk for Alzheimer's disease independent of APOE genotype.

Age of Onset↗
PubMed2000

CFTR mutations in three Latin American countries.

We analyzed 192 cystic fibrosis (CF) alleles in three Latin American countries: Mexico, Colombia, and Venezuela. Mutation screening was performed by polymerase chain reaction (PCR) and a reverse dot blot detection kit that enables determination of 16 of the most common CF mutations worldwide. Mutations were detected in 47.9% of the screened CF alleles. The most prevalent CF allele was DeltaF508 (39. 6%). The remaining 16 non-DeltaF508 detectable mutations represented 8.3% of the CF alleles. Among them, the G542X, N1303K, and 3849+10kb C>T were the most common. Although the frequency of DeltaF508 described here is lower than that reported for Caucasian populations, including in Spain, it is remarkable that mutation prevalences found in this study resemble those observed in Spain. Two of these mutations, G542X and 3849+10kb C>T, that were relevant in this analysis, have a particularly high incidence in Spanish communities. The low frequency of DeltaF508 described here may be explained by the Amerindian, Caucasian, and Black admixture that occurred in Latin America after the discovery of the New World, and also by the probable occurrence of mutations contributed by the original natives, which were undetectable in this analysis.

Colombia↗
PubMed2000

Investigation of the increased incidence of gonorrhoea diagnosed in genitourinary medicine clinics in England, 1994-6.

OBJECTIVES: To determine important risk factors associated with cases of gonorrhoea in England, and whether any particular risk groups were associated with the substantial rise in numbers of cases seen between 1994 and 1996. DESIGN: Two retrospective cross sectional surveys. SETTING: 70 randomly selected genitourinary medicine (GUM) clinics in England. SUBJECTS: 10% of all gonorrhoea patients attending GUM clinics in England in 1994 (847 patients) and 1996 (1146 patients). MAIN OUTCOME MEASURES: For risk factors in 1996 (study 1), unadjusted rates per 100,000 population aged 14-70 and relative rates (RR) with 95% confidence intervals (CIs). For the change in risk factors between 1994 and 1996 (study 2), adjusted odds ratios (ORs) with 95% CIs, derived from logistic regression analyses of data on patients in 1996, with patients in 1994 as the comparison group. RESULTS: The incidence of gonorrhoea in 1996 was higher in homosexual males (812 per 100,000; RR = 30.2, CI = 25.2 to 36.0) compared with heterosexual males (27 per 100,000); in black Caribbeans (467 per 100,000; 21.4, 17.9 to 25.5) and black Africans (235 per 100,000; 10.8, 7.5 to 15.5) compared with white people (22 per 100,000); and in previous GUM clinic attenders (433 per 100,000; 37.93, 35.46 to 40.56) compared with those who had not attended previously (11 per 100,000). However, most patients were either white or heterosexual. Heterosexual patients in 1996 were significantly more likely to have reduced sensitivity to penicillin (2.55, 1.20 to 5.41) than those in 1994. Male homo/bisexual patients in 1996 were significantly more likely to be from the north west (3.77, 1.45 to 9.80) and to have either reduced sensitivity (2.63, 1.03 to 6.73) or complete resistance (1.98, 1.03 to 3.78) to penicillin, compared with those in 1994. CONCLUSIONS: Homo/bisexual men and the black Caribbean population in England experience a disproportionate burden of gonococcal infections, however, the bulk of diagnoses are in white heterosexuals. No single risk group was associated with the rise in numbers of cases between 1994 and 1996. Resistance to penicillin is widespread and has increased in homo/bisexual men, and it is possible that a rise in treatment failures has, to some extent, enhanced transmission of gonorrhoea and contributed to the rise in numbers of diagnoses in this group.

Adolescent↗
PubMed2000

Effects of niacin-bound chromium and grape seed proanthocyanidin extract on the lipid profile of hypercholesterolemic subjects: a pilot study.

Hypercholesterolemia, a significant cardiovascular risk factor, is prevalent in the American population. Many drugs lower circulating cholesterol levels, but they are not infrequently associated with severe side effects. Accordingly, natural means to lower cholesterol levels safely would be welcomed. We examined 40 hypercholesterolemic subjects (total cholesterol 210-300 mg/dL) in a randomized, double-blind, placebo-controlled study. The four groups of ten subjects received either placebo bid, chromium polynicotinate (Cr) 200 microg bid, grape seed extract (GSE) 100 mg bid, or a combination of Cr and GSE at the same dosage bid. Over two months, the average percent change +/- SEM in the total cholesterol from baseline among groups was: placebo -3.5% +/- 4, GSE -2.5% +/- 2, Cr -10% +/- 5, and combination -16.5% +/- 3. The decrease in the last group was significantly different from placebo (p < 0.01). The major decrease in cholesterol concentration was in the LDL levels: placebo -3.0% +/- 4, GSE -1.0% +/- 2.0, Cr -14% +/- 4.0, and the combination -20% +/- 6.0. Again, the combination of Cr and GSE significantly decreased LDL when compared to placebo (p<0.01). HDL levels essentially did not change among the groups. Also, there was no significant difference in the triglyceride concentrations among the groups; and no statistically significant differences were seen in the levels of autoantibodies to oxidized LDL (Ox-LDL). However, the trend was for the two groups receiving GSE to have greater decreases in the latter parameter, i.e., -30.7% and -44.0% in the GSE and combined groups in contrast to -17.3% and -10.4% in the placebo and chromium groups. We determined the number of subjects in each group who decreased autoantibodies to oxidized LDL greater than 50% over eight weeks and found these ratios among groups: placebo = 2/9, Cr = 1/10, GSE = 6/10, and combined = 3/8. Thus, 50% of subjects (9/18) receiving GSE had a greater than 50% decrease in autoantibodies compared to 16% (3/19) in the two groups not receiving GSE. No significant changes occurred in the levels of circulating homocysteine and blood pressure among the four groups. We conclude that a combination of Cr and GSE can decrease total cholesterol and LDL levels significantly. Furthermore, there was a trend to decrease the circulating autoantibodies to oxidized LDL in the two groups receiving GSE.

Analysis of Variance↗
PubMed1999

Etiology and incidence of pressure ulcers in surgical patients.

This experimental study was designed to identify the etiology of pressure ulcers in a surgical sample and to evaluate a special OR mattress overlay in preventing pressure ulcer development. Surgical patients (N = 413) were randomized to receive "usual perioperative care" or the new mattress overlay. Over six postoperative days, 89 patients (21.5%) developed pressure ulcers, primarily stage I. Only 2% developed stage II or IV ulcers. Patients with ulcers were statistically older, had diabetes, were smaller in body mass, had lower Braden Scale scores on admission, and used the new mattress overlay (P < .02). Pressure ulcers that presented as "burns" or ecchymosis did not deteriorate to stage III or IV ulcers during the study. The mattress overlay was not effective in preventing pressure ulcer development.

Age Factors↗
PubMed1999

Breast conservation therapy in affiliated county, university, and private hospitals.

BACKGROUND: Breast conservation therapy (BCT) offers equivalent survival to modified radical mastectomy in patients with early-stage (I and IIa) breast cancer, but is utilized in less than 50% of eligible patients. While patient demographics have been linked to BCT rates, we suspected that physician influence was a major factor. The purpose of this study was to compare BCT at three affiliated centers staffed by similarly trained surgeons yet serving widely disparate populations, in order to assess the importance of physician influence on the utilization of BCT. METHODS: Tumor registry data were reviewed from 1993 through 1997 at affiliated city/county (CH), university (UH), and private hospitals (PH). Data were analyzed for clinical stage, treatment, and age of patient. RESULTS: The utilization of BCT for stage I and IIa breast cancer is similar at the three hospitals: 45% of patients at CH, 55% of patient at UH, and 57% of patients at PH (P>0.05). Rates of BCT were similar across all patient age groups at all sites. CONCLUSIONS: Similar BCT utilization rates can be achieved despite widely disparate patient populations. The three affiliated hospitals are staffed by surgeons with similar training, and all offer a multidisciplinary approach to breast cancer care. This suggests that physician influence may override patients' socioeconomic issues in providing optimal breast cancer therapy.

Adult↗
PubMed1999

Obesity stigmatization and coping: relation to mental health symptoms, body image, and self-esteem.

OBJECTIVE: To create inventories of stigmatizing situations faced by obese people and ways of coping with stigmatization, and to examine how stigma and coping are related to psychological distress in an obese patient population. DESIGN: Study 1: Items were generated by asking obese people to list stigmatizing situations they had encountered and their ways of coping. Study 2: Obese patients were surveyed about the frequency with which they encountered each form of stigmatization and employed each form of coping. Cross-sectional data on current psychological adjustment were obtained. SUBJECTS: Study 1: 63 obese patients (body mass index, BMI > 40 kg/m2); 38 obese non-patients, seven professionals who work with obese patients and 32 obese female authors from the print media. Study 2: 112 gastric bypass patients (BMI 33.9-80.9 kg/m2) and 34 less obese patients (BMI 27.1-57.2 kg/m2). MEASUREMENT: Study 1: Collection of stigmatizing situations and coping responses. Study 2: Frequency of stigmatizing experiences and coping responses, psychological symptoms, body image, and self esteem measures. RESULTS: Study 1 resulted in two objective questionnaires, consisting of 50 situations and 99 responses. Study 2 found that stigmatization is a common experience, and that obese subjects frequently engage in some effort to cope with stigma. More frequent exposure to stigmatization was associated with greater psychological distress, more attempts to cope, and more severe obesity. Certain coping strategies are associated with greater distress.

Adaptation, Psychological↗
PubMed1998

Preparticipation sports examination.

The preparticipation physical exam is a very important aspect for the care and safety of active and athletic individuals. Objectives of the evaluation include the discovery of conditions that may be life-threatening or disabling, that may limit participation, or that predispose to injury. The exam is not designed to exclude individuals from participation, but rather to assist athletes in safe participation. Although the preparticipation exam should not substitute for the individual's regular routine health care, it is often the only exposure many of these adolescents have to a physician, and therefore offers a unique opportunity for health care evaluation and screening.

Adolescent↗
PubMed1998

Phase II trial of liposomal daunorubicin in the treatment of AIDS-related pulmonary Kaposi's sarcoma.

PURPOSE: Kaposi's sarcoma (KS) is the most common tumor in patients with AIDS and can be fatal in patients with lung involvement. Systemic chemotherapy is the most effective treatment for pulmonary KS. We thus conducted this study to determine the efficacy of liposomal daunorubicin in the treatment of patients with pulmonary KS. METHODS: Patients with biopsy-proven, symptomatic pulmonary KS were accrued. Liposomal daunorubicin was given at a dose of 60 mg/m2 intravenously every 2 weeks. Response was monitored by chest radiographs, pulmonary function tests, arterial blood gases, and grading of pulmonary symptoms. RESULTS: Fifty-three male patients were accrued. The median CD4+ lymphocyte count was 13/microL (range, 0 to 200); 70% reported a prior AIDS-defining opportunistic infection. All patients were symptomatic, with cough reported in all patients, shortness of breath in 94%, and hemoptysis in 55%. The mean study entry diffusing capacity of carbon monoxide (DLCO) was 58.5% (percent of predicted). The median dose of liposomal daunorubicin delivered was 360 mg/m2 (range, 60 to 1,380). More than 75% of patients had complete or partial resolution of baseline pulmonary symptoms. Complete or partial improvement in DLCO was observed in 22%; complete or partial resolution of radiographic abnormalities was reported in 32%. The most common treatment-related toxicity was neutropenia, which occurred in 85%. There were no instances of cardiac toxicity observed, even at high cumulative doses. CONCLUSION: Liposomal daunorubicin at 60 mg/m2 is safe and active in patients with pulmonary KS. Trials combining liposomal daunorubicin with other active agents in KS should be considered.

Acquired Immunodeficiency Syndrome↗
PubMed1997

A polymorphism in the presenilin 1 gene does not modify risk for Alzheimer's disease in a cohort with sporadic early onset.

Mutations in the presenilin 1 gene account for many cases of early onset familial Alzheimer's disease. Homozygosity for the 'T' allele of a polymorphism in the presenilin 1 gene has previously been reported to double the risk for Alzheimer's disease in a late onset Caucasian sample. Here we report that this polymorphism does not incur risk in a case control sample of early onset Alzheimer's disease, possibly suggesting a different disease etiology between the early and late onset forms.

Adult↗
PubMed1997

E280A PS-1 mutation causes Alzheimer's disease but age of onset is not modified by ApoE alleles.

A single base substitution of a glutamic acid to an alanine codon 280 was found in the presenilin-1 (PS-1) gene on chromosome 14 in affected individuals in each of seven Colombian early-onset Alzheimer's disease (AD) kindreds. The mutation segregated with disease in kindreds tested. In the largest kindred (C2), the maximum two-point lod score between the mutation and AD was Z = 8.14 at theta = 0. The presence of a single mutation and the common geographic origin, with all families from the state of Antioquia, suggest a founder effect in this population. This finding is supported by the observation of a rare haplotype inherited with AD in all kindreds. These kindreds form the largest collection of AD cases with the same PS-1 mutation and the same educational, environmental, and ethnic background in which to study the phenotypic effect of putative risk factors, such as the epsilon4 allele of apolipoprotein E (ApoE) or head trauma. Of the few AD cases having a history of head trauma, the age of onset was not lowered. No effect of ApoE genotype on the age of onset was detected. Previous investigations of the effect of ApoE genotype on the age of onset were confounded by small patient numbers, familial clustering of ApoE genotypes, and combining data from unrelated families with different mutations.

Adult↗
PubMed1997

Differential modification of dopamine transporter and tyrosine hydroxylase mRNAs in midbrain of subjects with Parkinson's, Alzheimer's with parkinsonism, and Alzheimer's disease.

The molecular characteristics of midbrain dopamine (DA) neurons have been extensively studied in Parkinson's disease (PD). No such studies of the characteristics of midbrain DA neurons in Alzheimer's disease (AD) or Alzheimer's disease with parkinsonism (AD/Park) have been published. We examined the levels of tyrosine hydroxylase (TH) protein, and the expression of TH and dopamine transporter (DAT) mRNAs, in midbrain neurons of PD, AD, and AD/Park cases. In PD, the loss of TH protein in the ventral tier of the substantia nigra pars compacta (SNpc) of the PD group in accompanied by severe losses in the number of neurons that express TH mRNA and DAT mRNA (74% loss). Remaining neurons show a shift to higher concentrations of TH mRNA but a shift to lower concentrations of DAT mRNA per cell. Hence, there is evidence that compensation in the remaining neurons can elevate concentrations of TH mRNA and lower DAT mRNA. Alternatively, there may be a predilection for a loss of neurons with high levels of DAT mRNA and low TH mRNA levels within the SNpc of PD cases. There was no change in TH protein but an elevation of TH mRNA concentrations per neuron without any change in concentrations of DAT mRNA in the AD group. The AD/Park group did not exhibit changes in the level of TH protein, but showed a small loss (26%) of neurons in the SNpc and a greater loss in other regions of the midbrain (43-53%). Remaining DA neurons showed a marked shift to lower concentrations of DAT mRNA per neuron and a nonsignificant shift in cellular concentration of TH mRNA to higher levels. This is consistent with our previous work showing that with AD/Park there is a significant reduction in the number of DAT sites located on DA terminals in the striatum, but the midbrain neurons have not died. Our results indicate that the differential regulation of mRNAs encoding TH and DAT is similar in the parkinsonian disorders (PD and AD/Park) even though the degree of cell death is very different. This might suggest that compensatory events occur in these DA neurons in AD/Park that are similar to those in PD and that result in differential effects on mRNAs encoding TH and DAT proteins.

Aged↗
PubMed1997

Receptivity to protective garments among the elderly.

Hip fractures among elders resulting from falls are a growing concern as the proportion of elders increases and health care costs mount. A recent innovation is the development of an undergarment worn to protect against hip injuries. This study attempted to determine whether a community population of elders would be receptive to wearing such a garment and the characteristics of those who would and would not be receptive. It was assumed that receptivity can be predicted by variables that have been shown to relate to risks of falling. Predictor characteristics represent three domains: demographic/predisposition, health/mobility, and social support. A logistic regression procedure was employed to determine the probability and odds of receptivity among elders given a profile of specific characteristics. Results were interpreted with reference to past research on risks of falling.

Accidental Falls↗