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Biomedical subjects

J Farmer

Publications and source records attributed to J Farmer.

At least 55 records · Page 3Linked to original sources
PubMed1995

Site selection for Mars exobiology.

The selection of sites on Mars that have a high priority for exobiological research is fundamental for planning future exploration. The most immediate need is to identify targets for high resolution orbital imaging during the Mars Observer and Mars '94/'96 missions that can be used to refine site priorities for surface exploration. We present an objective approach to site selection whereby individual sites are selected and scored, based on the presence of key geological features which indicate high priority environments. Prime sites are those that show evidence for the prolonged activity of liquid water and which have sedimentary deposits that are likely to have accumulated in environments favorable for life. High priority areas include fluvio-lacustrine (stream-fed lake systems), springs, and periglacial environments. Sites where mineralization may have occurred in the presence of organisms (e.g. springs) are given high priority in the search for a fossil record on Mars. A systematic review of Viking data for 83 sites in the Mars Landing Site Catalog resulted in the selection of 13 as being of exobiological interest. The descriptions of these sites were expanded to address exobiological concerns. An additional five sites were identified for inclusion in the second edition of the MLSC. We plan to broaden our site selection activities to include a systematic global reconnaissance of Mars using Viking data, and will continue to refine site priorities for exobiological research based on data from future missions in order to define strategies for surface exploration.

Exobiology↗
PubMed1994

Baseline characteristics of subjects in the Lipoprotein and Coronary Atherosclerosis Study (LCAS) with fluvastatin.

A total of 429 subjects (79 women and 350 men), aged 35-75 years, have been enrolled in a randomized clinical trial of fluvastatin therapy for hypercholesterolemia. The progression and regression of atherosclerotic lesions will be assessed by quantitative angiography and positron emission tomography (PET) after 2.5 years of treatment. Patients were included in the trial if they had angiographically documented lesions that occluded 30-75% of the diameter of a major coronary vessel. Of the 429 subjects, 99 were also studied by PET at rest and during static exercise of sustained handgrip combined with administration of dipyridamole. All subjects were instructed in an American Heart Association/National Cholesterol Education Program (AHA/NCEP) Step I or Step II diet. Of the total, 107 subjects (25%) had low density lipoprotein cholesterol (LDL-C) > or = 160 mg/dL and were given cholestyramine, 8 g/day. All subjects were randomized to placebo or fluvastatin, the newest 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor to be introduced into the U.S. market. Fluvastatin is entirely synthetic and is similar in efficacy to the other available HMG-CoA reductase inhibitors. Its pharmaceutical profile (i.e., low systemic exposure) makes fluvastatin a good candidate for use in combination lipid-lowering therapy. The majority of subjects were recruited through a community campaign and the remainder through cardiac catheterization laboratories and the medical records of hospitals in the Texas Medical Center. Approximately 8,500 prospects from the community campaign were screened and 272 were randomized, a conversion rate of approximately 3%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Unusual immunostaining pattern of chromogranin in normal urothelium and in transitional cell neoplasms.

We report an unusual pattern of immunostaining for chromogranin A in 24 transitional cell carcinomas (TCC). Positive immunostaining was seen with chromogranin A antisera in 10 of 16 urinary bladder TCC, neither of 2 prostatic TCC, 3 of 3 ureteral TCC and 2 of 3 metastatic TCC. This staining was demonstrated within the cytoplasm of transitional cells at all levels of the neoplastic epithelium, including cells near the basement membrane and at the free surface (umbrella cells). In 5 of 7 cases there was also immunoreactivity of the non-neoplastic urothelium. Immunostaining with neuron-specific enolase and synaptophysin was negative in all of these cases and no neuro-secretory granules were identified in 7 cases examined by electron microscopy. This pattern of immunostaining is probably due to reactivity with chromogranins or certain chromogranin-like proteins in the transitional cells, particularly in the umbrella cells.

Carcinoma, Transitional Cell↗
PubMed1994

Family functioning, social support and depression after traumatic brain injury.

Functional outcome after traumatic brain injury (TBI) is thought to be dependent upon effective social support and avoidance of depressive episodes. Research indicates that post-injury changes often occur in the family's functioning, hence impacting the family's ability to provide the needed social support. Social support, in turn, has been hypothesized to work as a buffer between significant life event and levels of depressive symptoms. Thus poor social support after a TBI, due to changes in family functioning, could result in depressive episodes for the person with a TBI. This paper empirically examines this question by investigating whether social support is predictive of depression in persons who have sustained a TBI. Thirty-nine persons who had sustained TBI were interviewed to assess their family functioning, perceived social support, and current depressive symptomatology. The results showed that the effective use of problem-solving and behavioural coping strategies by the family in response to TBI was significantly related to lower levels of depression in the person who sustained the TBI. However, perceived social support was not predictive of depression.

Adaptation, Psychological↗
PubMed1993

Development and evaluation of drop-in centers operated by mental health consumers.

As part of a statewide initiative begun in 1989 to promote consumer involvement, the Pennsylvania Office of Mental Health initially funded the development of nine consumer-operated drop-in centers. This paper describes some of the programs and services developed by the centers and presents results of a survey of consumers' use of and satisfaction with services. During the six-month survey period, a total of 478 consumers used services; average daily attendance at each center was 28. Most centers had one paid position supplemented by heavy use of volunteers. Most projects had collaborative relationships with a few providers who maintained a low profile in daily operations. Although consumers were highly satisfied with the drop-in centers, they desired improvements in the number of paid staff, hours of operation, management, and transportation.

Ambulatory Care↗
PubMed1992

Psammomatoid ossifying fibroma of the orbit.

Psammomatoid ossifying fibroma of the orbit is a distinctive solitary fibro-osseous lesion of the orbital bones that histologically has characteristic small, round structures resembling psammoma bodies within a benign spindle cell stroma. We describe a 19-year-old woman with this uncommon orbital tumour.

Adult↗
PubMed1990

Parental injury prevention endeavors: a function of health beliefs?

Investigating parents' beliefs about injury prevention may yield important information for planning preventive interventions. A comprehensive description of parents' beliefs about injury prevention is presented in this study, and effects of child age and sex are described. In addition, a health belief model was successfully used to predict parent-reported teaching of safety skills and preventive environmental interventions. The model successfully cross-validated the prediction in two independent samples. Parents reported low feelings of susceptibility or worry about injury. The variables most associated with parental preventive endeavors were the belief that intervention can avoid injury, a realistically high appraisal of the amount of time involved, and feelings of high knowledge and competence to teach safety skills. Implications of these data for designing more effective behavioral interventions are described.

Accident Prevention↗
PubMed1989

A study of Salmonella typhi isolated in Suez Canal area. Biotyping, phage typing and colicinogenic property.

In this work a total of 82 strains of Salmonella typhi were isolated from Egyptian patients diagnosed as quiry enteric fever. These cases were from Ismalia, Suez and port Said Areas. The strains fell in 16 phage types. Phage types N, 40, E1, and degraded Vi were the commonest phage type in Ismailia, while phage types degraded Vi and C1 were the commonest in Port Said. Phage types Di-N, degraded Vi, A and C1 were the commonest in Suez. Chemotyping of Salmonella typhi showed that the majority of the strains belonged to chemotype I (82%), and the rest belonged to chemotype II (18%). Colicin production was negative and all the strains were susceptible to the currently used antibiotics.

Bacteriophage Typing↗
PubMed1987

Standardized physician preparation of death certificates.

One method for determining cause of death in a clinical trial is to use standard nosological coding of death certificates. In order to look at an alternative approach, the Hypertension Detection and Follow-up Program (HDFP) assessed underlying causes of death through the use of three physicians. These physicians were trained and standardized in the proper recording of cause of death on death certificates. Each physician completed a death certificate for each of the 768 deaths in the HDFP, utilizing all available information, including HDFP records, plus any additional hospital and autopsy records. The new standardized death certificates were then transmitted to a panel of three nosologists who coded the cause of death. The physician preparation procedure was compared with a procedure wherein a panel of three nosologists coded the original death certificate for the underlying cause of death. The procedures agreed on the three-digit International Classification of Disease, Adapted code in 60.1% of the cases. The agreement rate improved to 72.5% when disease codes were collapsed into broad disease categories utilized in the HDFP.

Adult↗
PubMed1987

Effects of purified (AIN-76A) and natural-ingredient (NIH-07) diets on responses of BALB/c and B6C3F1 female mice to estradiol.

Female BALB/c and B6C3F1 mice were examined after a 3-wk exposure to dietary estradiol (0, 400, 800, 1600, and 3200 ppb) in a purified (AIN-76A) or a natural-ingredient (NIH-07) diet. The use of AIN-76A was associated with a 9-13% greater (p less than 0.001) body weight and a 36-43% higher (p less than 0.001) serum cholesterol in both mouse genotypes when compared to mice fed NIH-07. Conversely, when fed NIH-07, both mouse genotypes had a 20-22% higher (p less than 0.003) serum urea nitogren and 2-3.5% higher erythrocyte count (p less than 0.001) and hemoglobin concentration (p less than 0.04) than when fed AIN-76A. Reduced erythrocyte parameters suggest that chronic feeding of the purified diet might result in anemia. No significant compound or diet-related differences were noted for serum creatinine, alanine aminotransferase, aspartate aminotransferase, or gamma-glutamyl transferase. Although there was no diet effect on absolute or differential white blood cell count, estradiol caused a decrease in the total white blood cell count (p less than 0.014) and an increase in the percentage of polymorphonuclear leukocytes (p less than 0.014) in BALB/c and decreased the percentage of lymphocytes (p less than 0.005) in B6C3F1 females. In addition, estradiol increased uterine weight and inhibited thymic and splenic weights in one or both genotypes. Spleen and thymus weight responses to estradiol were not significantly influenced by diet. However, the uterine weight responses to estradiol were apparently influenced by diet in both genotypes. In B6C3F1 mice, the uterus weighed more at each level of estradiol when mice were fed AIN-76A compared to NIH-07 diet. In BALB/c mice, this was true only at the two lower dietary concentrations of estradiol. In conclusion, mice fed the purified diet, AIN-76A, differed from those fed the cereal-based diet, NIH-07, in hematology, clinical chemistry, and uterine weight response to estradiol.

Animal Feed↗
PubMed1986

Spontaneous CSF otorrhea from tegmen and posterior fossa defects.

Spontaneous cerebrospinal otorrhea (SCSFO) from tegmen or posterior fossa defects is uncommon. Twenty-nine cases have been detailed in the literature to date. We report an additional four cases from three patients. This group of 33 cases of SCSFO from tegmen or posterior fossa defects is characterized by certain clinical features. These patients are usually older adults (mean age 48 years, range 8 months to 80 years). Aural fullness with a serous appearing middle ear effusion, or clear otorrhea, often subsequent to tube myringotomy, are the usual initial symptoms. Meningitis was the initial manifestation in eight patients (24%), and ultimately occurred in an additional four patients (12%). The pathophysiologic basis for SCSFO from tegmen defects is discussed. Methods for diagnosing and treating CSF otorrhea from tegmen defects are reviewed.

Adolescent↗
PubMed1986

Mineralization in in vitro cultures of rabbit marrow stromal cells.

Localized regions of mineralization were found in confluent cultures of rabbit marrow fibroblastic cells. The mineralized tissue developed within clusters of giant fat cells in the spaces between the cells. Investigations with light and electron microscopy demonstrated that in these sites there was some differentiation of the fibroblastic cells in an osteogenic direction, shown by changes to more polygonal shapes, and the synthesis of well-banded collagen similar to that found in bone tissue. Differentiation may be due, in part, to increased cell density in a confined space. Growth of the mineralized tissue was observed in the living cultures with a fluorescence microscope. Electron probe microanalysis confirmed that the mineral formed was hydroxyapatite. Initiating sites of mineralization included membranous vesicular bodies, lipid, and products of cellular degeneration. Once initiated, mineralization appeared to spread rapidly into adjacent collagenous and other structures, suggesting the appearance of a mixture of skeletal-type and dystrophic mineralization.

Animals↗
PubMed1984

Monocular nystagmus in infancy and early childhood.

Of 11 young children (six girls and five boys, ranging in age from 4 to 14 months) with monocular nystagmus, six were found to have chiasmal tumors whereas only four had spasmus nutans. Differentiating features between these two groups included decreased vision and optic nerve anomalies (including four cases of optic nerve hypoplasia) in the tumor group. However, we found that no consistent clinical finding absolutely separates these groups. We therefore recommend that all infants and children with monocular nystagmus or the other features of spasmus nutans should undergo computed tomographic scanning.

Cranial Nerve Neoplasms↗
PubMed1983

Professional behavior in the orthopedic resident. A method for evaluation and development.

The affective behavior of orthopedic residents may be the most important indicator of their ability to function as orthopedic surgeons. Seven years of personal observations were combined with the experience of more than 300 participants in the Basic Course for Orthopaedic Educators, and recorded from the results of a recent questionnaire answered by members of the Association of Orthopaedic Chairmen. The affective domain was found to supply the answers to most of the problems of orthopedic residents. An evaluation of affective behavior early in the residency program may help to determine residents' suitability for a career in orthopedic surgery.

Affect↗
PubMed1982

The effect of metocurine and metocurine-pancuronium combination on intraocular pressure.

Maintenance of a normal to low intraocular pressure during ocular surgery is of critical importance. The prime considerations for anaesthetic management include adequate depth of anaesthesia, normal carbon dioxide and arterial oxygen tensions, stable cardiovascular status and avoidance of stimuli likely to raise central venous pressure. Non-depolarizing muscle relaxants are associated with a reduction in intraocular pressure. Metocurine, a non-depolarizing relaxant, formerly known as dimethyltubocurarine, has been recently reintroduced into clinical practice. Metocurine has been reported to be 1.8 times more potent than d-tubocurarine and has the clinically advantageous cardiovascular effects of stable heart rate and mean blood pressure with minimal associated histamine release. When combined with pancuronium, metocurine potentiates the neuromuscular blocking properties, so that small doses of both drugs in combination produce effective neuromuscular block. This study was designed to assess the suitability of metocurine 0.3 mg.kg-1 and metocurine 0.08 mg.kg-1 plus pancuronium 0.02 mg.kg-1 as muscle relaxants for ocular surgery. The results demonstrated that metocurine and metocurine-pancuronium combination in the above doses combined with sodium thiopentone 5 mg.kg-1 produced ideal conditions for intubation of the trachea in 4.45 (+/- 0.19 SE) minutes and 4.35 (+/- 0.16 SE) minutes respectively. In both treatment groups intraocular pressure was reduced below control values and a pattern of intraocular pressure stability ideal for ocular surgery was obtained during the 10 minutes observation period. The delayed onset of sufficient paralysis for tracheal intubation - 4.45 (+/- 0.19 SE) minutes for metocurine and 4.35 (+/- 0.16 SE) minutes for the combination - makes these techniques unsuitable for emergency ocular surgery because of the long interval when the airway is unprotected.

Adolescent↗