Search PubMed⌕ Search

Biomedical subjects

H Smith

Publications and source records attributed to H Smith.

At least 901 records · Page 50Linked to original sources
PubMedDate not supplied

Indication of thioglucosidase activity in extracts of Neisseria gonorrhoeae.

The recent demonstration of a host-derived inducer of gonococcal resistance to complement-mediated killing by human serum in purified serum and red blood cell fractions, which contained small glucopeptides with cysteine as one of the constituent amino acids, prompted an investigation of Neisseria gonorrhoeae for thioglucosidase activity. This involved an examination of supernatants of sonicated gonococci for thioglucoside hydrolysis by following, spectroscopically, the hydrolysis of 6-purine beta-D-glucothiopyranoside to 6-mercaptopurine and glucose. Extracts of N. gonorrhoeae were found to hydrolyse this thioglucoside. A substantial activity was present in a fraction with the same order of molecular weight as plant thioglucosidases. This led us to suspect the presence of a thioglucosidase in N. gonorrhoeae.

Glycoside Hydrolases↗
PubMedDate not supplied

Bromine in human tissue.

The normal levels of bromine in human tissue are given and their use in the interpretation of levels found when over-exposure is a possibility is described. Bromine is "normally" distributed in human tissue as are essential trace elements. This allows a bromine (microgram) to chlorine (mg) ratio to be established (3.2) above which bromine exposure must be considered. The bromine concentrations in sections of hair can be used to establish the time of administration even when small amounts are ingested, but owing to the long half-life (about 15 days) found in human tissue interpretation after multiple doses may be difficult.

Bromine↗
PubMedDate not supplied

Interfering basic materials in urine from racing greyhounds.

Three quinoline amines, 2-aminomethylquinoline, 2-hydroxymethylquinoline and quinaldine (2-methylquinoline), are identified in greyhound urine. These amines can interfere in the analysis of greyhound material for basic drugs. This is a special problem in ultraviolet spectrometry since their extinction coefficients are high. Reference analytical data for these quinoline amines and for six related compounds are given. The techniques used are infrared spectrometry, ultraviolet spectrometry, fluorometry, thin-layer chromatography, gas chromatography and mass spectrometry.

Amines↗
PubMedDate not supplied

Conservation of the expression of Dll, en, and wg in the eye-antennal imaginal disc of stalk-eyed flies.

We studied the developmental basis of exaggerated eye span in two species of stalk-eyed flies (Cyrtodiopsis dalmanni and Sphyracephala beccarn). These flies have eyes laterally displaced at the end of eyestalks, and males have greatly exaggerated eye span, which they use as a sexual display. To investigate eye span development we have compared eye-antennal disc morphology and the expression of three key regulator genes of Drosophila head development, Distal-less (Dll), engrailed (en), and wingless (wg), in the stalk-eyed flies and Drosophila. We found great similarity in the basic division of the disc into anterior-antennal and posterior-eye portions and in the general patterning of Dll, en, and wg. Unexpectedly, our results showed that although the eye and antenna are adjacent in adult stalk-eyed flies, their primordia are physically separated by the presence of an intervening region between the anterior and posterior portions of the disc. This region is absent from Drosophila eye-antennal discs. We chose two stalk-eyed fly species that differed in the degree of eye-stalk exaggeration but surprisingly we found no corresponding difference in the size of the en-wg expression domains that mark the boundaries of the dorsal head capsule primordia. In summary, our expression data establish the regional identity of the eye-antennal disc and provide a framework from which to address the developmental genetics of hypercephaly.

Animals↗
PubMedDate not supplied

Clinical validation of automated spirometry used in surveys of large occupational groups: comparison with conventional water spirometry.

An accurate, rugged automated spirometer which provides immediate data is useful both clinically and for screening large groups with various environmental exposures. Because the need for such surveys has been increasing, we compared a computerized mass flow-meter with a conventional water spirometer. The same forced expiration was measured by both instruments in the laboratory and during an occupational survey. Mean values for forced vital capacity (FVC) were 96 cc greater by the automated technique in the laboratory (this equals 2.2% of the value by the conventional method, with a correlation, r, of 0.998) and 97 cc greater in the field (2.3% of the conventional method; r = 0.995). Differences between the two methods in the laboratory and field for forced expiratory volume in one second (FEV 1.0) were +24 cc (0.68%; r = 0.996) and +47 cc (1.6%; r = 0.996) and for forced expiratory flow (FEF)25-75--179cc/sec (4.18%; r = 0.968) and -63 cc/sec (2.1%; r = 0.992), respectively. For FVC and FEV1.0, the differences between paired values were less than or equal to 10% of the value by water spirometry in all instances and less than or equal to 5% in 95.5% and 96% of comparisons, respectively. For FEF 25-75 the differences between paired values were less than or equal to 20% in 97.2% and less than or equal to 10% in 84.7% of comparisons. These findings confirm the validity of the measurements provided by the automated spirometer.

Autoanalysis↗
PubMedDate not supplied

Violent and nonviolent girls: contrasting perceptions of anger experiences, school, and relationships.

Arrests of American girls for assault and weapons charges are rapidly increasing, at rates exceeding those for boys. Yet research on girls' violence is scant. We surveyed a national sample of 213 girls (ages 9-19) via personal interview or an Internet questionnaire, regarding anger precipitants and behaviors, interpersonal relationships, and experiences of discipline at home and school. Girls were categorized as violent (n = 54) if they had been suspended or expelled from school for fighting or bringing a weapon, or charged with a violent offense by the juvenile justice system. The remaining girls (n = 159) were categorized as nonviolent. The anger of violent girls tended to be intense and generalized, while the anger of nonviolent girls was precipitated by specific situations of injustice. Correlates of feeling angry enough to hit or hurt someone were loneliness, unfair treatment by adults, not liked by classmates, and somatic anger symptoms. Violent girls were significantly more likely to dislike school and perceive school discipline as unfair. Both groups of girls held negative views of television violence and curfews. Although girls with well-established patterns of aggression need psychotherapy, school-based interventions such as emotional literacy and violence prevention programs may also be helpful. Mental health nurses are well prepared to serve in a consultative role to schools, assisting in the development and delivery of violence prevention programming.

Adolescent↗
PubMedDate not supplied

Lessons for human influenza from pathogenicity studies with ferrets.

In research on influenza, little attention has been given to factors that determine the patterns of infection in human adults or infants and the severity of disease. Ferret influenza has been used to elucidate the following facets of pathogenicity that bear on these questions about human disease: the differential infectivity of virus strains for the upper respiratory tract (URT); the reasons for less severe infection of the lower respiratory tract (LRT) than of the URT; why pneumonia is rare; and why strains differ in the production of LRT infection. The origin of fever has been defined; viruses have been shown to differ in fever-producing components. Poor spread of virus from the respiratory tract to other susceptible tissues and rarity of fetal infection have been explained. Death in neonatal ferrets due to influenza with either a syndrome akin to cot death or viral pneumonia have been elucidated, and protection of the young by immunized mothers has been demonstrated.

Animals↗
PubMedDate not supplied

John Keats: poet, patient, physician.

John Keats, son of an ostler , was born in London in 1795. Despite an early interest in literature he was, surprisingly, apprenticed to an apothecary and continued his medical training at Guy's Hospital, obtaining the Licentiate of the Society of Apothecaries in 1816. He never practiced medicine. His early poems were not well received, and for the young poet with very slender means, life was difficult. Tragedy was added to difficulty when tuberculosis, which had already caused the death of his mother and uncle, became apparent in his brother Tom, whom Keats nursed through his illness when the brothers were living together in Hampstead . Subsequently Keats developed the disease, but despite its rapid progress, he managed in a single year - 1819 - to produce some of the finest lyrical poetry in the language. He went to Italy in the hope of obtaining a cure but died in Rome in 1821, aged 25. Medicine certainly contributed to the man, but also something to the poet, Keats; his training and his family and personal experience of tuberculosis speak for themselves. More subtly , his medical experience influenced in some degree his ideas and even his choice of words. The interrelations of poet-patient and trainee-physician are examined in this essay.

Famous Persons↗
PubMedDate not supplied

Training for child day care staff and for licensing and regulatory personnel in the prevention of infectious disease transmission.

Recognition of the importance of preventing disease transmission in day care facilities has increased as more mothers of infants join the work force and as evidence of the spread of disease in day care mounts; the effectiveness of licensing agencies has eroded with the shrinking of resources, and limited compliance with current standards exists. Both the staff of child day care facilities and the personnel who are responsible for licensing and regulating such facilities require ongoing training in issues of health promotion and disease prevention. The curriculum of all training programs should include, in addition to child development, topics of general health and safety, such as safety hazards and the risk of infection, knowledge of the infectious diseases likely to be encountered in day care, the use of routine screening tests, the principles of good nutrition, the components of routine health assessment, and the special concerns of disabled, abused, and neglected children. Health professionals in the community and licensing personnel should function as channels for the dissemination of new information as it becomes available; inspection of facilities for the purpose of licensing provides an excellent opportunity for training staff. Monitoring has been found to heighten awareness and improve performance. Employees' compliance with regulations has been shown to increase when staff members are trained as advocates of health.

Child Day Care Centers↗
PubMedDate not supplied

Organizational approach to medication administration in day care.

Because young children have numerous infections and other conditions that require medication during the day, medication administration is an issue for every day care program. While all day care programs may not accept responsibility for administration of medication, every program must have a policy about it. Where medications are given in day care, care givers need training to handle their responsibility appropriately. Health professionals have a role in determining when the need for a medication is great enough to warrant the transfer of responsibility from parents to day care personnel and to attempt to adjust regimens to avoid the need for medication in day care, where possible. Health professionals should also help parents and care givers understand when to use medication, including over-the-counter medications, which are so strongly advertised. Safety precautions, intervals, doses, procedures, and techniques for administration of medication in day care are areas of knowledge and skill for which guidelines are available.

Child Day Care Centers↗
PubMedDate not supplied

Immature circulating lymphocytes in severely malnourished Guatemalan children.

The percentage of peripheral blood lymphocytes forming rosettes with sheep erythrocytes (E-rosettes) was determined in 33 severely malnourished Guatemalan children, and in two groups of clinically well but mildly growth retarded children from the same environment. Mean E-rosettes in the acutely ill patients was lower than the value observed in the mildly malnourished children, although there was considerable overlap between groups. These data differ from previously published studies of severely malnourished children from other parts of the world in that not all patients had decreased values for E-rosettes, in contrast to the uniform depression reported by others. As all patients were clinically similar, the results suggest that there may be specific nutrient defects associated with protein-energy malnutrition that particularly affect immune function. In addition, in vitro incubation of lymphocytes from the acutely malnourished children with the thymic factor, thymosin fraction 5, increased the percentage of E-rosettes in a dose-dependent fashion. These data suggest that immature, thymosin-responsive T cells are present in circulation. It is possible that in vivo thymosin administration may be beneficial for malnourished individuals.

Cell Differentiation↗
PubMedDate not supplied

Magnetic resonance imaging of the spinal cord in spinal dysraphisms.

Magnetic resonance imaging (MRI) was performed 49 times in 42 patients with spinal dysraphism. Scoliosis and a changing neurological picture were the primary indications. Spinal cord anomalies included hydromyelia, diastematomyelia, lipoma, thickened filum terminali, and spinal cord atrophy. All but one patient exhibited Arnold-Chiari malformation. Twenty-two of the 42 patients had computed tomography (CT) scans, myelograms, or operations that corroborated the 41 MRI findings. Three false-positive MRI findings of hydromyelia and no false-negative studies were observed. MRI is a noninvasive investigative technique that provides more information than myelography or CT in defining spinal cord anatomy in spinal dysraphism.

Arnold-Chiari Malformation↗
PubMedDate not supplied

Angiogenesis in gynecological oncology-mechanism of tumor progression and therapeutic targets.

The purpose of this article is to review the current literature pertaining to various angiogenic stimulators and angiogenesis inhibitors in gynecological malignancies and the relevance of these markers in the prognosis of these diseases. We also summarize the antiangiogenic drugs currently in development and in clinical use in gynecological oncology. The information was obtained from a computer search of MEDLINE for studies published in the English language regarding angiogenesis and angiogenesis inhibitors in gynecological malignancies between 1970 and December 2003; additional sources were identified through cross-referencing. In ovarian cancer, various different angiogenic activators have been found to correlate with microvessed density (MVD), stage, lymph node and peritoneal metastasis, and survival. In cervical cancer, correlation has been seen between increased angiogenic markers and stage, grade, tumor size, and survival. Studies in endometriat cancer show correlation of angiogenic markers with stage, grade, MVD, and survival. Whereas, in gestational trophoblastic neoplasm (GTD) only few markers have been studied, and some correlated with progression. Information on anti angiogenic drugs currently in ongoing and upcoming trials in gynecological malignancies is also presented. Angiogenesis factors may have a prognostic role to play in patients with gynecological cancers and should continue to be investigated as clinically useful tumor markers. Antiangiogenic-targeted therapies offer an attractive strategy for clinical investigation in gynecologic oncology.

Animals↗
PubMedDate not supplied

Effect of neonatal capsaicin on peptide-containing primary afferent fibres, eosinophil distribution and hyperresponsiveness in rat lung tissue following experimentally induced eosinophilia.

Treatment of neonatal rats with capsaicin causes a 92.4% loss of calcitonin-gene-related-peptide-immunoreactive unmyelinated sensory afferent fibres in the airways epithelium, vascular smooth muscle and perivascular adventitial layer of lung tissue compared with vehicle-treated controls. Rats were administered Sephadex particles i.v. 8-10 weeks after either capsaicin or vehicle treatment at birth in order to induce a granulomatous tissue inflammation, peripheral blood eosinophilia and pulmonary eosinophil invasion [Laycock et al., Int Arch Allergy Appl Immunol 1986;81:363-367]. The animals also exhibited lung hyperreactivity in vitro in response to carbachol and serotonin (5HT). In Sephadex-treated rats, capsaicin pretreatment did not affect the number of inflammatory cells in peripheral blood, the number of eosinophils in lung tissue, or the distribution of eosinophils in the adventitial tissue of blood vessels. Potencies of concentration-related contractures of lung tissue to 5HT and carbachol were increased by 50- to 100-fold in Sephadex-treated animals compared to controls, but in neither group was potency influenced by capsaicin pretreatment at birth. Recruitment and subsequent regional distribution of inflammatory cells in lung tissue and the increase in lung hyperresponsiveness exhibited in this model of asthma do not appear to involve neuropeptides released from primary afferent neurones.

Afferent Pathways↗
PubMedDate not supplied

Hyperapobetalipoproteinemia in a kindred with familial combined hyperlipidemia and familial hypercholesterolemia.

A child showed a type IIb lipoprotein pattern and triglyceride-enriched cutaneous xanthomas before 1 year of age. The proband and 9 of 18 relatives had elevated plasma levels of low density lipoprotein (LDL) B protein; of these nine relatives, four had elevated LDL of increased density while five had elevated LDL of normal density. Compared with normal LDL, LDL of increased density had less cholesteryl ester and free cholesterol, more apolipoprotein B and triglyceride, and a lower molecular weight and flotation rate (Sf degrees). Patients with LDL of increased density had higher mean plasma levels of triglycerides, very low density lipoproteins, and intermediate density lipoproteins, but lower levels of high density lipoproteins than those with elevated LDL of normal density. Multiple lipoprotein patterns in the father's family suggested the presence of familial combined hyperlipidemia (FCH). The mother of the proband and two of her relatives had type IIa lipoprotein patterns and tendon xanthomas, compatible with familial hypercholesterolemia (FH). High affinity binding, internalization, and degradation of 125I LDL in cultured fibroblasts from the proband and his mother were reduced two- to threefold compared with normal cells, while LDL receptor activity in the proband's father was normal. This unusual proband has apparently inherited both FCH and FH.

Apolipoproteins A↗