Health beliefs and practices of rural elders

Understanding the rural elderly is essential to developing effective programs to prevent disease and promote health.

Magnetic resonance imaging of body fat of athletes compared with controls, and the oxidative metabolism of estradiol

The extent of 2-hydroxylation of estradiol (E2), which yields a non-estrogenic metabolite (2-OHE1), increased significantly with decreasing subcutaneous fat (ScF)/total volume percent (TV%) and total fat (TF)/TV% evaluated by magnetic resonance imaging (MRI) for five athletes during low- and high-intensity training, and four controls. The increase in 2-hydroxylation with decreasing adiposity was associated with anovulation and amenorrhea among the athletes.

Transvaginal intra-abdominal impalement injury

Impalement injuries due to sexual activity are highly unusual and variable. We have described a case of transvaginal impalement injury of the rectum, bladder, omentum, and mesentery manifested by vaginal bleeding. The patient could not recount how she had been injured. Management of such an injury requires extensive initial evaluation and a multidisciplinary approach to therapy.

A second neutralizing epitope of B19 parvovirus implicates the spike region in the immune response

We used 18 monoclonal antibodies against B19 parvovirus to identify neutralizing epitopes on the viral capsid. Of the 18 antibodies, 9 had in vitro neutralizing activity in a bone marrow colony culture assay. The overlapping polypeptide fragments spanning the B19 structural proteins were produced in a pMAL-c Escherichia coli expression system and used to investigate the binding sites of the neutralizing antibodies. One of the nine neutralizing antibodies reacted with both VP1 and VP2 capsid proteins and a single polypeptide fragment on an immunoblot, identifying a linear neutralizing epitope between amino acids 57 and 77 of the VP2 capsid protein. Eight of nine neutralizing antibodies failed to react with either of the capsid proteins or any polypeptide fragments, despite reactivities with intact virions in a radioimmunoassay, suggesting that additional conformationally dependent neutralizing epitopes exist.

Susceptibility contrast imaging of cerebral blood volume: human experience

Magnetic resonance (MR) can offer a unique window on the structure/function relationships in the brain, by utilizing the established link between tissue function, metabolism, and hemodynamics. This report focuses on recent applications of MR-based cerebral blood volume (CBV) imaging in humans. Our methodology uses high-speed "single-shot" or echo planar imaging techniques, which provide the necessary temporal resolution for mapping the rapid cerebral transit of contrast agents. These MR CBV mapping techniques have been used to study normal human brain task activation and in the clinical study of patients with brain tumors. In the latter, positron emission tomography imaging was used for functional metabolic and CBV correlation. Susceptibility contrast CBV imaging should allow us to improve our understanding of the relationship between the detailed physiology and morphology of the microvascular bed and functional attributes of the brain. These techniques can be applied to understanding fundamental questions of cognitive neuroscience and can aid in improving diagnostic sensitivity and specificity in various neuropathologies.

cAMP-inducible chloride conductance in mouse fibroblast lines stably expressing the human cystic fibrosis transmembrane conductance regulator

A cAMP-inducible chloride permeability has been detected in mouse fibroblast (L cell) lines upon stable integration of a full-length cDNA encoding the human cystic fibrosis transmembrane conductance regulator (CFTR). As indicated by a Cl(-)-indicator dye, the Cl- permeability of the plasma membrane increases by 10- to 30-fold within 2 min after treatment of the cells with forskolin, an activator of adenylyl cyclase. The properties of the conductance are similar to those described in secretory epithelial cells; the whole-cell current-voltage relationship is linear and there is no evidence of voltage-dependent inactivation or activation. In contrast, this cAMP-dependent Cl- flux is undetectable in the untransfected cells or cells harboring defective cDNA constructs, including one with a phenylalanine deletion at amino acid position 508 (delta F508), the most common mutation causing cystic fibrosis. These observations are consistent with the hypothesis that the CFTR is a cAMP-dependent Cl- channel. The availability of a heterologous (nonepithelial) cell type expressing the CFTR offers an excellent system to understand the basic mechanisms underlying this CFTR-associated ion permeability and to study the structure and function of the CFTR.

An interactive perspective on the health beliefs & practices of rural elders

1. In this study, major themes involving health were closely tied to an affective response of "feeling good" and cognitive appraisal of health status as "being able to function." 2. Rural elderly who participated in the study reported engaging in at least one activity to maintain their health and tended to rely on their own appraisal and resources to manage health problems. 3. Half of the participants indicated a need for services such as blood pressure and diabetic screening, health education classes on diet, cholesterol reduction, hypertension and diabetes management, new therapies in health care, and life management counseling.

Crystallization and preliminary X-ray studies of annexin IV (endonexin), a calcium-dependent phospholipid-binding protein

Annexin IV (endonexin) has been purified from chicken liver and crystallized by the vapour diffusion method. Crystals which diffract to at least 2.2 A have been obtained. They belong to space group R3 and have unit cell dimensions of a = b = 99.4 A, c = 96.2 A, alpha = 90 degrees, beta = 90 degrees, gamma = 120 degrees. There is one molecule of 32,500 Da per asymmetric unit.

Hemoptysis in a 49-year-old man. An unusual presentation of a sporadic disease

Although amebiasis is prevalent in tropical and subtropical areas, it occurs sporadically in the United States. Pleuropulmonary involvement is seen in about 20 percent of the patients with amebic liver abscesses. We describe a patient with pleuropulmonary amebiasis who complained of hemoptysis but had no gastrointestinal symptoms. This rather unusual presentation caused a considerable delay in securing the diagnosis.

Identification of mutations in regions corresponding to the two putative nucleotide (ATP)-binding folds of the cystic fibrosis gene

Additional mutations in the cystic fibrosis (CF) gene were identified in the regions corresponding to the two putative nucleotide (ATP)-binding folds (NBFs) of the predicted polypeptide. The patient cohort included 46 Canadian CF families with well-characterized DNA marker haplotypes spanning the disease locus and several other families from Israel. Eleven mutations were found in the first NBF, 2 were found in the second NBF, but none was found in the R-domain. Seven of the mutations were of the missense type affecting some of the highly conserved amino acid residues in the first NBF; 3 were nonsense mutations; 2 would probably affect mRNA splicing; 2 corresponded to small deletions, including another 3-base-pair deletion different from the major mutation (delta F508), which could account for 70% of the CF chromosomes in the population. Nine of these mutations accounted for 12 of the 31 non-delta F508 CF chromosomes in the Canadian families. The highly heterogeneous nature of the remaining CF mutations provides important insights into the structure and function of the protein, but it also suggests that DNA-based genetic screening for CF carrier status will not be straightforward.

The principal axes transformation--a method for image registration

We have developed a computational technique suitable for registration of sets of image data covering the whole brain volume which are translated and rotated with respect to one another. The same computational method may be used to register pairs of tomographic brain images which are rotated and translated in the transverse section plane. The technique is based on the classical theory of rigid bodies, employing as its basis the principal axes transformation. The performance of the method was studied by simulation and with image data from PET, XCT, and MRI. It was found that random errors in determining the brain contour are well tolerated. Progressively coarser axial sampling of data sets led to some degradation, but acceptable performance was obtained with axial sampling distances up to 10 mm. Given adequate digital sampling of the object volume, we conclude that registration by the principal axes transformation can be accomplished with typical errors in the range of approximately 1 mm. The advantages of the technique are simplicity and speed of computation.

Neuropeptide-Y enhances luteinizing hormone (LH)-releasing hormone-induced LH release and elevations in cytosolic Ca2+ in rat anterior pituitary cells: evidence for involvement of extracellular Ca2+ influx through voltage-sensitive channels

The present studies were designed to investigate the mechanism by which neuropeptide-Y (NPY) augments the effect of LHRH to stimulate the release of LH from cultured rat anterior pituitary cells. Anterior pituitary cells from ovariectomized rats were enzymatically dispersed, cultured for 3 days, and then exposed to various secretagogues during 3-h incubations. As reported by this laboratory previously, NPY alone (100 nM) did not affect LH release, but significantly enhanced the LH response to 1 nM LHRH. This facilitatory action of NPY was mimicked by the dihydropyridine Ca2+ channel agonist Bay K 8644 (1 microM), and the enhancement of LHRH-induced LH release by either NPY or Bay K 8644 was prevented by the dihydropyridine antagonist nitrendipine (1 microM). Nitrendipine alone reduced the response to LHRH by approximately 25%, but did not affect basal LH release. In contrast, NPY failed to amplify the release of PRL in response to TRH, another Ca2(+)-mobilizing hormone. To test whether NPY also enhances the increase in cytosolic Ca2+ induced by LHRH, anterior pituitary cells were acutely dispersed into single cell suspensions, loaded with the fluorescent Ca2+ probe Indo-1 AM, and analyzed with a UV laser in an EPICS-753 flow cytometer at a rate of 500 cells/sec for 200 sec. The ratio of intracellular fluorescence resulting from Ca2+ bound to the Indo-1 to the fluorescence from Indo-1 alone (Indo-1 ratio), which is an index of the concentration of free cytosolic Ca2+, was determined for each cell. Approximately 7% of anterior pituitary cells responded to LHRH (1 or 10 nM) with significant increases in Indo-1 ratios, indicative of an increase in the concentration of free cytosolic Ca2+. EGTA (2.5 mM) reduced the basal Indo-1 ratios and attenuated, but did not abolish, the initial increase in response to LHRH, consistent with the initial extracellular Ca2+ influx-independent phase of the response to LHRH. NPY alone (100 nM) did not affect the Indo-1 ratios in anterior pituitary cells, but pretreatment with the peptide for 10 min before the scans significantly augmented the Indo-1 ratio response to 10 nM LHRH. This effect of NPY was also blocked by EGTA. Taken together, these biochemical and pharmacological studies suggest that NPY enhances the release of LH stimulated by LHRH by increasing extracellular Ca2+ entry, possibly by selectively affecting that component of the response involving dihydropyridine-sensitive L-type voltage-sensitive Ca2+ channels during the initial stages of the cellular response to LHRH.

Calcitonin inhibits thyrotropin-releasing hormone-induced increases in cytosolic Ca2+ in isolated rat anterior pituitary cells

Calcitonin (CT) and related peptides, such as CT gene-related peptide and salmon CT (sCT)-like peptide, are present in the rat nervous system and the pituitary gland, and sCT markedly inhibits basal and TRH-stimulated PRL release from anterior pituitary (AP) cells. Because TRH-induced PRL release is known to involve increases in cytosolic free Ca2+ derived from both extracellular and intracellular sources, the objective of the present study was to test whether sCT interferes with this effect. Secretogogue-induced elevations of cytosolic free Ca2+ ([Ca2+]i) in acutely dispersed AP cells were monitored using the fluorescent Ca2+ indicator Indo-1 AM and flow cytometry. AP cells were enzymatically dispersed to single cell suspensions and loaded with 20 microM Indo-1 AM for 30 min. Indo-1-loaded AP cells were scanned at a rate of approximately 500 cells/sec for 200-300 sec in a flow cytometer, and the ratio of fluorescence due to Ca2+ bound to Indo-1 to free Indo-1 (Indo-1 ratio), which is an index of [Ca2+]i, was determined for each cell. Under basal conditions, AP cells showed stable Indo-1 ratios during the scans, and 100% of the cells responded to the Ca2+ ionophore ionomycin with increases in the Indo-1 ratio. Approximately 25-30% of the AP cells responded to a 1 microM pulse of TRH with marked increases in the Indo-1 ratio, indicative of increases in [Ca2+]i, with the response consisting of two phases, an initial rapid rise that was unaffected by the presence of EGTA in the extracellular environment, followed by a decrease to a sustained secondary phase that was completely eliminated by EGTA. In a normal extracellular Ca2+ environment, pretreatment with 100 nM sCT almost totally inhibited the response to 1 microM TRH. In EGTA-pretreated AP cells, the initial EGTA-insensitive phase of the TRH-induced [Ca2+]i increase was also abolished by prior exposure to sCT. These results suggest that sCT inhibits TRH-stimulated PRL release in AP cells by attenuating the TRH-induced increase in [Ca2+]i, an effect that probably occurs as a consequence of inhibition of the stimulatory effect of TRH on the Ca2+/phospholipid messenger system.

Direct angioplasty of the basilar artery in baboons

The lower portion of the basilar artery is a site of significant disease, both aneurysmal and stenotic, but has been considered inaccessible via traditional surgical approaches. A baboon model was used to evaluate the feasibility of a direct surgical reconstruction via a transoral-transclival approach, utilizing temporary occlusion of the basilar artery. An arteriotomy was performed and either repaired primarily or a venous patch graft was sutured in place. All animals survived the surgery; one suffered fatal postoperative upper airway obstruction, but the other four were neurologically intact at the time of death. Patency at the site of repair was confirmed both angiographically and histologically. We conclude that temporary clamping in conjunction with direct reconstruction of the basilar artery is feasible in this primate model. Future studies will focus on further applications of this technique.

Identification of the cystic fibrosis gene: chromosome walking and jumping

An understanding of the basic defect in the inherited disorder cystic fibrosis requires cloning of the cystic fibrosis gene and definition of its protein product. In the absence of direct functional information, chromosomal map position is a guide for locating the gene. Chromosome walking and jumping and complementary DNA hybridization were used to isolate DNA sequences, encompassing more than 500,000 base pairs, from the cystic fibrosis region on the long arm of human chromosome 7. Several transcribed sequences and conserved segments were identified in this cloned region. One of these corresponds to the cystic fibrosis gene and spans approximately 250,000 base pairs of genomic DNA.

Bedside blood gas and electrolyte monitoring in critically ill patients

A major advantage of near-patient testing is time savings that facilitate important diagnostic and therapeutic decisions. Recent technologic advances have made available a number of systems that allow for near-patient testing. The reliability of these instruments must be validated in the clinical setting in the hands of their intended users. We evaluated the Gemstat blood gas, electrolyte, and Hct portable analyzer in the critical care setting when used by numerous individuals with no previous laboratory training. Blood gas, Na, K, and Hct results were highly correlated with those from the clinical laboratories (PaO2, r = .96; PaCO2, r = .92, pH, r = .96; Na, r = .93; K, r = .95; Hct, r = .91). The Gemstat represents a new generation of portable, rapid, safe, and accurate instruments that are well suited for ICU settings. The instrument can facilitate clinical management of patients, and may improve patient care.

Neurological features of HIV-related disease in Glasgow

The neurological features of 10 patients with HIV-related disease seen in Glasgow between July 1984 and May 1988 are described. Two of these patients presented with ARC and eight with AIDS. Six patients showed features consistent with a diagnosis of AIDS-dementia complex, one had cerebral toxoplasmosis, one had CNS lymphoma, one had a probable drug-induced encephalopathy and one patient had a meningoencephalitis of undetermined cause. Seven of these patients have now died. The implications of these findings are discussed.

Identification and regional localization of DNA markers on chromosome 7 for the cloning of the cystic fibrosis gene

To facilitate mapping of the cystic fibrosis locus (CF) and to isolate the corresponding gene, we have screened a flow-sorted chromosome 7-specific library for additional DNA markers in the 7q31-q32 region. Unique ("single-copy") DNA segments were selected from the library and used in hybridization analysis with a panel of somatic cell hybrids containing various portions of human chromosome 7 and patient cell lines with deletion of this chromosome. A total of 258 chromosome 7-specific single-copy DNA segments were identified, and most of them localized to subregions. Fifty three of these corresponded to DNA sequences in the 7q31-q32 region. Family and physical mapping studies showed that two of the DNA markers, D7S122 and D7S340, are in close linkage with CF. The data also showed that D7S122 and D7S340 map between MET and D7S8, the two genetic markers known to be on opposite sides of CF. The study thus reaffirms the general strategy in approaching a disease locus on the basis of chromosome location.

Phase I study of a murine monoclonal anti-lipid A antibody in bacteremic and nonbacteremic patients

Nine patients with suspected gram-negative bacterial sepsis were studied to determine the safety, pharmacokinetics, and immunogenicity of XMMEN-0E5, a murine immunoglobulin M monoclonal antibody directed against the core lipid A region of bacterial endotoxin. Antibody was administered by single intravenous infusion of 1 to 4 h duration at doses ranging from 0.1 to 15 mg/kg. Five patients had positive blood cultures for gram-negative bacteria, one patient had Torulopsis septicemia, one patient had gram-negative bacterial meningitis, and two patients were culture negative. No evidence of antibody-mediated toxicity was observed at any dose level. The serum half-life of the antibody was approximately 10 h at doses of 0.1 to 7.5 mg/kg and approximately 18 h at a dose of 15 mg/kg. No apparent difference in clearance of antibody was observed between bacteremic and nonbacteremic patients. Human anti-mouse antibodies were detected in the sera of three evaluable patients that received doses equal to or greater than 2.0 mg/kg but not in patients that received lower doses of antibody. This study demonstrates that XMMEN-0E5 is well tolerated at doses from 0.1 to 15 mg/kg and may be immunogenic at doses of 2.0 mg/kg and above. Controlled trials to establish the efficacy of this antibody in the treatment of gram-negative bacteremia are indicated.

A rapid and sensitive method for measuring the conditional emotional response. II: On-the-baseline excitatory conditioning and extinction

The present study outlines a rapid and sensitive on-the-baseline conditional emotional response (CER) procedure. Using rats as the experimental subject, the method detects delay conditioning, incubation, extinction and spontaneous recovery. In addition, the method detects conditional responding using electric shock ranging from 0.23 to 0.50 mA as the unconditional stimulus. Because of its speed and sensitivity, the method shelters the subject from unnecessary long-term deprivation and pain.

Linkage of cystic fibrosis to the pro alpha 2(I) collagen gene, COL1A2, on chromosome 7

A linkage has been detected between the locus for cystic fibrosis (CF) and the pro alpha 2(I) collagen gene (COL1A2) which is located in the region q21.3----q22.1 of chromosome 7. Based on the combined linkage data derived from 50 informative two-generation nuclear families collected in Canada and Denmark, the distance between COL1A2 and CF is estimated to be 19 centiMorgans. Close linkage has also been detected between COL1A2 and the DNA marker D7S15 (formerly D0CRI-917) and the serum enzyme activity marker paraoxonase (PON), both of which have previously been found linked to CF. The results of the two-point and three-point linkage analyses indicate that the most probable order of these four genetic loci is COL1A2-D7S15 - PON - CF.

Cystic fibrosis locus defined by a genetically linked polymorphic DNA marker

A polymorphic DNA marker has been found genetically linked, in a set of 39 human families, to an autosomal recessive gene that causes cystic fibrosis (CF), a disease affecting one in 2000 Caucasian children. The DNA marker (called D0CRI-917) is also linked to the PON locus, which by independent evidence is linked to the CF locus. The best estimates of the genetic distances are 5 centimorgans between the DNA marker and PON and 15 centimorgans between the DNA marker and the CF locus, meaning that the location of the disease gene has been narrowed to about 1 percent of the human genome (about 30 million base pairs). Although the data are consistent with the interpretation that a single locus causes cystic fibrosis, the possibility of genetic heterogeneity remains. The discovery of a linked DNA polymorphism is the first step in molecular analysis of the CF gene and its causative role in the disease.

Government policies and the cost of doing research

The changes in the political economy of science are the natural outcome of two trends: science itself has become a more capital-intensive activity at the same time that federal support for research programs has slowed its growth. The results of the accumulating shortfall in the capital base for university research--increased seeking of support from private industry, efforts to circumvent peer review and competitive allocation, and a falling-out between institutions and investigators over how to divide up available resources--threaten to unravel what has been an extraordinary way of doing science.