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Biomedical subjects

D Armstrong

Publications and source records attributed to D Armstrong.

At least 775 records · Page 43Linked to original sources
PubMedDate not supplied

Lymphocyte autofluorescence: a screening procedure for neurodegenerative diseases.

We examined the buffy coats from 12 consecutive patients with neurodegenerative diseases to determine the value of autofluorescence study by fluorescence microscopy in parallel with electron microscopy, as a rapid and inexpensive screening procedure for lymphocyte inclusions characteristic of neuronal ceroidlipofuscinoses. Four patients (3 with neuronal ceroidlipofuscinoses and 1 with Hallervorden-Spatz syndrome) had discrete, yellow-orange, 1-2 microns autofluorescent granules in the cytoplasm of some lymphocytes. These granules corresponded to characteristic inclusions of neuronal ceroidlipofuscinoses demonstrated by electron microscopy. Five patients (4 undiagnosed or nonspecific disease, and 1 with Leber congenital amaurosis) had hazy green cytoplasmic autofluorescence which correlated with parallel tubular arrays in lymphocytes. The 3 patients with no autofluorescence had no ultrastructural lymphocytic inclusions. We conclude that buffy coat autofluorescence is a rapid and inexpensive method of identifying specimens that require electron microscopic confirmation, and the absence of autofluorescence of lymphocytes in a buffy coat specimen eliminates the necessity for electron microscopic examination. However, characteristic ultrastructural inclusions associated with neurodegenerative diseases may occur in other tissues, such as skin and conjunctiva.

Adolescent↗
PubMedDate not supplied

Relationship of lipid peroxides to diabetic complications. Comparison with conventional laboratory tests.

One hundred and seventy-three Arab patients with non-insulin-dependent diabetes mellitus (NIDDM) and 51 controls were examined. The routine laboratory tests of fasting blood sugar (FBS), glycosylated hemoglobin (HbA1c), fructosamine (FRA), and triglycerides (TG) were compared with lipid hydroperoxides (LHP) as detected by the thiobarbituric acid (TBA) method, which measures total TBA reacting substances (TBARS). All routine laboratory measures were elevated in the patient population. In the case of LHP, values in NIDDM were 491 +/- 183 mumol/L for men and 507 +/- 183 mumol/L for women, as compared with pooled normal values of 275 +/- 85 mumol/L. Seven patients with NIDDM undergoing hemodialysis were also elevated above normal (441 +/- 97 mumol/L). Comparisons between LHP and the other biochemical parameters indicated a positive statistical correlation with triglycerides (p less than 0.001); FBS, HbA1c, and FRA (p greater than 0.01). Patients with NIDDM on dietary control had somewhat lower LHP levels (441 +/- 135 mumol/L) than those receiving insulin (519 +/- 206 mumol/L), or oral hypoglycemic agents (518 +/- 177 mumol/L). Dietary maintenance also resulted in reduced FBS and HbA1c levels. Subdivision of patients according to duration of disease and by nationality showed that Kuwaiti nationals had slightly higher LHP values than did patients of other Arabic origin. Women patients (Kuwaiti and non-Kuwaiti) with NIDDM disease duration of greater than 10 years, had LHP levels above those of males (551 +/- 245 versus 478 +/- 126 mumol/L) and, as a group, showed significant enhancement of retinal complications (85.5% versus 55%). A statistically significant trend (p less than 0.08) could be demonstrated between the prevalence of retinopathy and increasing serum LHP levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Psychophysiological manifestations of anxiety in patients undergoing electrophysiology studies.

OBJECTIVE: To measure state anxiety and related physiological correlates at 3 selected times when patient education regarding electrophysiology (EP) studies is likely to occur: 24 hours before the EP study (pre-procedure teaching), 1 hour before the EP study (reinforcement of pre-procedure teaching), and 3 hours after the EP study (explanation of results; reinforcement of post-procedure instructions). DESIGN: Descriptive-exploratory. SETTING: Military medical treatment facility in mid Atlantic region. SUBJECTS: Thirty-two adults who underwent initial EP testing. OUTCOME MEASURES: The Spielberger State Anxiety score, frontalis muscle tension, heart rate, electrodermal activity, electrothermal feedback, and mean arterial pressure. METHODS: Outcome measures were obtained 1 day before (time 1), 1 hour before (time 2), and 3 hours after (time 3) the EP study. RESULTS: Both state anxiety scores and physiological variables indicated minimal psychophysiological reactivity. CONCLUSION: Patients undergoing initial EP studies experience moderate state anxiety and manifest a paradoxical pattern of autonomic responses over time. Moderate levels of state anxiety at each of the 3 assessment points would seem to indicate that patient education is appropriate at these times.

Adolescent↗
PubMedDate not supplied

Experimental approaches to age-related cognitive impairments.

Rats exhibit morphological, biochemical, and metabolic changes in their brains, as well as cognitive deficits, with aging. Aged rats were found to be significantly impaired compared to young rats in a water maze task and test of motor coordination, and show reduced locomotor activity and exploration. Although aged rats did exhibit deficits as a group, not all aged rats were impaired. Additionally, the subgroup that was impaired on one task was not necessarily the subgroup that was impaired on another task. The cholinergic projection neurons in the basal forebrain region were significantly atrophied in the aged rodent. The degree of atrophy was highly correlated with the cognitive impairment exhibited on the Morris water maze task. Swollen choline acetyltransferase (ChAT)-positive "plaque-like" structures were observed in the neocortex of the aged but not the young rats. Declines in cholinergic activity in the brain has also been observed during aging. Biochemical measurements of ChAT in the basal forebrain region of aged rats revealed small but consistent decreases in ChAT activity compared to young rats. General metabolic activity, measured by the 2-deoxyglucose method, was also decreased in the hippocampal CA1 and CA3 fields, the dentate gyrus, the medial septal-diagonal band area, and the prefrontal cortex of aged rats. There was a significant correlation between the decrease in glucose utilization and deficits on the Morris water maze. Most aged rats exhibit pathological EEG patterns as reflected by frequent long-duration high voltage neocortical spindles (HVS) during immobility. Bilateral lesions of the nucleus basalis and scopolamine treatment increased the incidence of HVS, thereby mimicking changes in the aged brain. We attempted to ameliorate the cognitive deficits observed in subgroups or impaired rats by either: (1) implanting fetal cells of basal forebrain origin into the hippocampus, or (2) infusing nerve growth factor (NGF) chronically into the lateral ventricle. The grafts appeared to facilitate an improvement in the ability of the impaired aged rats to perform in the Morris water maze. This improved performance was reversed by injections of atropine at doses that did not affect the behavior of young animals that performed well in the same task. These results suggest that enhancement of the cholinergic system could have an effect on the performance of the impaired aged animals. The study of the effects of infusions of NGF clearly demonstrate that the ability of impaired aged rats to remember what they had previously learned was increased after NGF treatment.(ABSTRACT TRUNCATED AT 400 WORDS)

Aging↗
PubMedDate not supplied

Problems in management of opportunistic fungal diseases.

Opportunistic fungal infections are now common and will become more common as a consequence of the use of various regimens of immunosuppressive therapy for a variety of diseases and because of AIDS. These infections can be broadly divided into those that take advantage of a neutrophil defect (e.g., candidiasis, aspergillosis, and mucormycosis) and those that take advantage of a T cell mononuclear phagocyte defect (e.g., cryptococcosis, histoplasmosis, and coccidioidomycosis). Problems in diagnosis have been apparent since these infections were first recognized. The usual clinical specimens are often not revealing, and attempts to develop special serologic and biochemical tests have been made for years, but progress has been slow. Problems in treatment stem first from a lack of an early diagnosis and second from a lack of drugs that are effective and relatively nontoxic. It is difficult to evaluate new drugs if we cannot make accurate diagnoses; this difficulty is compounded by the low rate of autopsies in the academic hospitals where such studies are conducted.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Extrapulmonary Pneumocystis carinii infections.

A case of disseminated infection with Pneumocystis carinii is presented, and the English-language literature is reviewed for cases of documented extrapulmonary infection with this organism. In this case--with P. carinii diffusely replacing the bone marrow and causing hepatic, adrenal, and glomerular tuft necrosis--the clinical illness and multiple-organ dysfunction attributed to disseminated P. carinii were more severe than had previously been described. Because the rate of extrapulmonary P. carinii infection found at autopsy in patients with AIDS is at least 2.5% at our institution, we caution against the routine use of aerosol rather than parenteral pentamidine for treatment of P. carinii pneumonia until additional data are available.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Empiric therapy for the immunocompromised host.

The use of empiric therapy for immunocompromised hosts has been one of the major advances in the management of such patients. Such therapy has been put into practice primarily for patients with neutropenia induced by cytotoxic chemotherapy. The empiric antibiotic regimens include in their coverage the bowel, skin, and intravenous-catheter flora anticipated for patients in a particular hospital. Less often, physicians treat empirically for opportunistic infections that complicate defects in helper cells, although empiric therapy for presumed Pneumocystis carinii pneumonia and Toxoplasma gondii infection of the central nervous system has become commonplace for patients infected with human immunodeficiency virus. Physicians also should consider environmental factors that expose patients to certain opportunistic organisms. Examples of such pathogens include Mycobacterium tuberculosis and Histoplasma capsulatum. The particular microorganisms considered to be opportunistic vary in different parts of the world and in different hospitals, and their designation as such may change rapidly. Multiple environmental exposures and immune defects, rather than just one factor, may be responsible for opportunistic infections and should be investigated and taken into account when empiric therapy is planned. Preventive measures, including simply rigorous hygiene, should precede and may obviate the need for empiric therapy.

Bacterial Infections↗
PubMedDate not supplied

Fungemia in a cancer hospital: changing frequency, earlier onset, and results of therapy.

Two hundred episodes of fungemia that occurred at Memorial Sloan-Kettering Cancer Center between January 1, 1978, and June 30, 1982, are reviewed and compared with those seen from 1974 through 1977. The total number of episodes of fungemia per year increased by 30.6%, episodes per 100 new lymphoma and solid tumor patients increased by 73% and 95%, respectively, and episodes per 100 new leukemia patients decreased by 50%. Fungemia also occurred earlier during hospitalization, and embolic skin lesions were a common early sign of Candida tropicalis fungemia. Mortality was not significantly different with and without amphotericin B therapy in fungemic patients with leukemia, lymphoma, or aplastic anemia (51 of 70 vs. 21 of 24) or solid tumors (29 of 36 vs. 29 of 43); however, some patients appeared to benefit from combination therapy with amphotericin B and flucytosine. The prevalence of disseminated candidiasis at autopsy was the same in treated (11 of 15) and untreated (8 of 11) patients with leukemia, lymphoma, and aplastic anemia, but it was significantly lower in treated (none of 8) than in untreated (5 of 11) patients with solid tumors.

Adult↗
PubMedDate not supplied

Cryptosporidium and cryptosporidiosis.

Cryptosporidium is a newly recognized human pathogen associated with severe enteritis and, perhaps, cholecystitis in immunocompromised patients, particularly those with the acquired immunodeficiency syndrome, and significant, though self-limited, diarrheal illness in the immunocompetent host. As more physicians look for this pathogen, the number of reported cases of cryptosporidiosis continues to increase. Although the prevalence of cryptosporidiosis in humans is not yet known, recent studies suggest that it is a common cause of diarrhea worldwide, particularly in young children. The pathogenic mechanisms by which Cryptosporidium causes enteritis and the factors of human host defense essential for eradication of this parasite have not been delineated. Acid-fast staining of stool is a quick and reliable way of diagnosing cryptosporidiosis. Although a vast array of therapeutic agents has been tried for this disease, there is currently no known effective therapy for cryptosporidial infection.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Outbreak of Mycoplasma pneumoniae infection among hospital personnel.

An outbreak of illness due to Mycoplasma pneumoniae occurred among employees of a large hospital. The spectrum of disease ranged from severe upper respiratory infection to multilobed pneumonia. No unusual increase in the incidence of respiratory illness due to this organism was observed in the surrounding community during the period under investigation. It was not possible to identify any single area of the hospital frequented by enough of the involved personnel to explain the spread of the infection among the hospital's employees. This is the first outbreak of M pneumoniae disease to be reported among hospital personnel.

Cross Infection↗
PubMedDate not supplied

Case report: Antemortem diagnosis of central nervous system strongyloidiasis.

Strongyloidiasis is usually a benign illness confined to the gastrointestinal tract. However, dissemination (hyperinfection syndrome) may occur, particularly in patients with impaired cell-mediated immunity. The diagnosis of hyperinfection syndrome is often made postmortem, and mortality is high, even when the disease is recognized during life. Central nervous system involvement with Strongyloides stercoralis has previously been recognized in only a few cases at postmortem examination, and in one case antemortem. We describe a patient with disseminated strongyloidiasis in whom central nervous system involvement was diagnosed antemortem. This patient developed multiple bacterial and fungal systemic and central nervous system infections as a complication of disseminated strongyloidiasis. The natural history of the disease in man, factors predisposing to dissemination, immunologic aspects of helminthic infection, and treatment modalities are discussed.

Animals↗
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Exploring fathers' experiences of pregnancy after a prior perinatal loss.

PURPOSE: To explore fathers' experiences of pregnancy after a prior perinatal loss. STUDY DESIGN AND METHODS: This phenomenological study used unstructured, in-depth interviews with four men whose wives were currently pregnant subsequent to previous perinatal loss in the second or third trimester. RESULTS: Regardless of the timing of the loss or their investment in the previous pregnancy, fathers expressed anxiety about the outcome of the subsequent pregnancy, a heightened sense of risk, and a need for increased vigilance. Themes concerning the intensity of the loss experience, dealing with grief, spirituality, supporting their spouse, influence of the previous loss, replacement of the loss, the importance of milestones, and change in world view were described. CLINICAL IMPLICATIONS: This study can provide insight for nurses into the needs of these families during a subsequent pregnancy and can help nurses to better support fathers during this critical time.

Adult↗
PubMedDate not supplied

Lymphogranuloma venereum presenting as superclavicular and inguinal lymphadenopathy.

A 46-year-old woman developed a febrile illness characterized by supraclavicular and inguinal lymphadopathy. The diagnosis of lymphogranuloma venereum was made by a fourfold rise in complement fixing antibody titer. Treatment with tetracycline was successful. Lymphogranuloma venereum can yield protean manifestations, and should be considered in the differential diagnosis of patients with constitutional symptoms and lymphadenopathy at any site.

Clavicle↗
PubMedDate not supplied

Combination therapy in a model of pulmonary aspergillosis.

The current treatment for pulmonary aspergillosis, amphotericin B, is toxic and not always effective. This study was done to evaluate combinations of amphotericin B with other agents in an animal model of pulmonary aspergillosis. Sprague-Dawley rats were treated with cortisone acetate, infected intratracheally with 10(6) spores of Aspergillus fumigatus, and followed daily for survival. Mortality among controls started on day 2, and it was 80% by day seven, whereas therapy with amphotericin B resulted in survival of all animals. When given alone, ketoconazole, 5-fluorocytosine and rifampin did not improve survival. The combination of ketoconazole with amphotericin B resulted in complete antagonism. When animals received a combination of aerosol amphotericin B prophylaxis two days prior to infection followed by treatments with SCH39304 or itraconazole seven days after infection, survival rates were superior as compared to animals that had received aerosol prophylaxis only. The combinations of either 5-fluorocytosine or rifampin with amphotericin B were not better than amphotericin B alone. While combinations with 5-fluorocytosine or rifampin appear not to offer any advantage over therapy with amphotericin B alone, additional studies to further evaluate the role of azoles in combination therapy are needed.

Amphotericin B↗