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D Rose

Publications and source records attributed to D Rose.

At least 55 records · Page 3Linked to original sources
PubMed1999

Central effects of 5-HT on respiratory rhythm in newborn rats in vivo.

The role of 5-HT in inducing apnoeas (a major element in sudden infant death syndrome) is controversial because while 5-HT is a respiratory depressant in vivo, it evokes respiratory analeptic effects when applied to the isolated brainstem of the newborn rat. In decerebrate newborn rats, the electrical activity of the diaphragm and that of a hypoglossally innervated tongue muscle, as well as the cardiac frequency (Fc), were recorded before and after the application of 5-HT and related agents to the floor of the IVth ventricle. To assess the spontaneous variability in inspiratory frequency (Fi) and Fc, a sham group was studied. A decrease in Fi was observed in response to 5-HT. This respiratory depressant effect was associated with an activation of the tongue muscle, but there was no change in Fc. Application of agonists elicited a small increase in Fi linked to activation of 5-HT1A receptors, and decreases in both Fi and the activity of the tongue muscle resulting predominantly from activation of 5-HT2 receptors. The decrease in Fi was much smaller in newborn rats than that reported in newborn kittens. Indeed, in newborn rats, we did not observe long-lasting apnoeas. Our results differ from those obtained from the newborn rat in vitro, inasmuch as in vivo 5-HT essentially depressed the respiratory rhythm generator. The role of the afferent system appears to be crucial in modulating the action of 5-HT.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed1999

Binocular and monocular detection of Gabor patches in binocular two-dimensional noise.

Contrast thresholds for detecting sine-wave Gabor patches in two-dimensional externally added random-pixel noise were measured. Thresholds were obtained for monocular and binocular signals in the presence of spatial correlated (identical) and uncorrelated (independent) noise in the two eyes. Measurements were obtained at four different spectral densities of noise (including zero). Thresholds were higher for monocular stimuli than for binocular, and higher in the presence of correlated noise compared to uncorrelated noise. The magnitude of binocular summation, similar in correlated and uncorrelated noise, decreased with increasing noise strength. The independent contributions of internal noise and sampling efficiency to detection were analysed. Sampling efficiencies were higher for binocular than for monocular viewing for both types of noise, with values being higher with uncorrelated noise. Binocular stimuli showed a lower equivalent noise level compared to the mean monocular case for both types of noise.

Contrast Sensitivity↗
PubMed1999

The historical roots of the theories of local signs and labelled lines.

The theories of labelled lines and local signs are commonly invoked to explain numerous perceptual phenomena. These theories postulate that perceptual systems use information about which nerve cells or which information channels are activated by the stimulus. The origins of this idea in nineteenth century German psychophysics are traced. From Descartes's idea of a dualistic mind, Kant's idea of a mental ability to conceive space, Da Vinci's ideas of pictorial 'signs', and Müller's idea of 'specific nerve energies' to explain perceptual qualities, Steinbuch, Lotze, and others derived the conclusion that neural-level signs exist that signal stimulus location to the mind. Helmholtz, Hering, and others soon suggested variations on this basic idea. By the time of James the theory had changed yet again. It was revived elsewhere in the 1920s and again in the 1970s, although used implicitly by many workers in between and since. Against a modern metaphysical background, however, a distinction between labels (hardware) and signs (symbols) is the minimum step needed towards an appropriate and comprehensive explanation of perceptual behaviour and experience.

History, 19th Century↗
PubMed1999

Economic determinants and dietary consequences of food insecurity in the United States.

This paper reviews recent research on the economic determinants and dietary consequences of food insecurity and hunger in the United States. The new Current Population Study (CPS) food insecurity and hunger measure shows that hunger rates decline sharply with rising incomes. Despite this strong relationship, confirmed in other national datasets, a one-to-one correspondence between poverty-level incomes and hunger does not exist. In 1995, 13.1% of those in poverty experienced hunger and half of those experiencing hunger had incomes above the poverty level. Panel data indicate that those who are often food insufficient are much more likely than food-sufficient households to have experienced recent events that stress household budgets, such as losing a job, gaining a household member or losing food stamps. Cross-sectional work also demonstrates the importance of food stamps because benefit levels are inversely related to food insufficiency. Concern for the dietary consequences of domestic food insufficiency is well placed; recent research shows that the odds of consuming intakes <50% of the recommended dietary allowance (RDA) are higher for adult women and elderly individuals from food-insufficient households. Preschoolers from food-insufficient households do not consume significantly lower amounts than those from food-sufficient households, but mean intakes for the rest of members in those very same households are significantly lower for the food insufficient. This research highlights the importance of food insecurity and hunger indicators, further validates the use of self-reported measures and points to areas of need for future research and interventions.

Adult↗
PubMed1999

Emotions and psychopathology.

Few psychological assessment instruments exist for Jamaicans. Studies that address the appropriateness of foreign instruments for Jamaicans are sparse and empirical focus on psychopathology and its aetiology in Jamaican adults is virtually nonexistent. The present study addressed these deficits via Confirmatory Factor Analyses (CFA) which revealed that factors on the Toronto Alexithymia Scale (TAS-20) and Brief Symptom Inventory (BSI) were not replicated for a Jamaican sample (N = 352). Exploratory Factor Analyses (EFA) on the TAS-20 revealed one factor labelled Unawareness and Confusion Regarding Emotions (UCRE). Also, EFA yielded six BSI dimensions labelled Somatic Complaints, Paranoia, Hostility, Mild Depression/Dysthymia, Major Depression with Psychotic Features, and Agoraphobia with Panic. Regression analyses on the Jamaican-based TAS-20 and BSI factors revealed a positive relationship between UCRE and each BSI factor and total BSI score. Mild Depression, Agoraphobia with Panic, Paranoia, Hostility, Mild Depression and Major Depression were higher for women and younger Jamaicans, respectively, but younger Jamaicans with higher UCRE scores had higher scores on Paranoia, Major Depression, and total score. The findings suggest that Jamaican mental health policy and programmes should focus on the difficulties some Jamaicans experience in recognising and expressing their emotions.

Adolescent↗
PubMed1998

A nematode kinesin required for cleavage furrow advancement.

Dividing cells need to coordinate the separation of chromosomes with the formation of a cleavage plane. There is evidence that microtubule bundles in the interzone region of the anaphase spindle somehow control both the location and the assembly of the cleavage furrow [1-3]. A microtubule motor that concentrates in the interzone, MKLP1, has previously been implicated in the assembly of both the metaphase spindle and the cleavage furrow [4-6]. To gain insight into mechanisms that might underlie interdependence of the spindle and the cleavage furrow, we used RNA-mediated interference (RNAi) to study the effects of eliminating MKLP1 from Caenorhabditis elegans embryos. Surprisingly, in MKLP1(RNAi) embryos, spindle formation appears normal until late anaphase. Microtubule bundles form in the spindle interzone and the cleavage furrow assembles; anaphase and cleavage furrow ingression initially appear normal. The interzone bundles do not gather into a stable midbody, however, and furrow contraction always fails before complete closure. This sequence of relatively normal mitosis and a late failure of cytokinesis continues for many cell cycles. These and additional results suggest that the interzone microtubule bundles need MKLP1 to encourage the advance and stable closure of the cleavage furrow.

Animals↗
PubMed1998

Motion perception: from phi to omega.

When human observers view dynamic random noise, such as television 'snow', through a curved or annular aperture, they experience a compelling illusion that the noise is moving smoothly and coherently around the curve (the 'omega effect'). In several series of experiments, we have investigated the conditions under which this effect occurs and the possible mechanisms that might cause it. We contrast the omega effect with 'phi motion', seen when an object suddenly changes position. Our conclusions are that the visual scene is first segmented into objects before a coherent velocity is assigned to the texture on each object's surface. The omega effect arises because there are motion mechanisms that deal specifically with object rotation and these interact with pattern mechanisms sensitive to curvature.

Humans↗
PubMed1998

"Painting" the target: how local molecular cues define synaptic relationships.

A majority of studies on neuronal growth cones focus on the features that particular groups of neurons share. In contrast, questions such as how specific growth cones respond very differently to the same extrinsic cues require cell-specific experimentation. The most succinct cell-specific growth cone responses occur during synaptic targeting. Recent studies have examined one specific growth cone, the Drosophila RP3 motoneuron growth cone, in variously altered microenvironments. In this review, we summarize how such studies are beginning to uncover the repertoire of extrinsic cues that influence the synaptic targeting of a single growth cone.

Animals↗
PubMed1998

Psychological and socio-medical aspects of HIV/AIDS: a reflection on publications in AIDS care (1989-1995).

It is necessary to consider the content and methods of AIDS social research publications for these represent research advances as well as current issues of concern for practitioners, communities and researchers alike. This article critically examines some of the research that has been conducted to date into social aspects of HIV and AIDS. It quantifies the content and major methodological style of publications in the journal AIDS Care from 1989 to 1995. The most commonly published topic area in AIDS Care, during this period was cultural and demographic issues (15.9%), followed by issues pertinent to the psychological impact of HIV (13.6%), sexual behaviour and condom use (11.3%) and policy and services (9.5%). Research and measurement issues were the least examined content area in AIDS Care 1989-1995 (2.6%). This article discusses possible variables that influence the style and topics that are published in AIDS Care and makes suggestions for authors to consider before embarking on future research projects or publications.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Household participation in the Food Stamp and WIC programs increases the nutrient intakes of preschool children.

We examined the effects of household participation in the Food Stamp and WIC Nutrition Programs on the nutrient intakes of preschoolers using data from the 1989-1991 Continuing Survey of Food Intake by Individuals. Nonbreastfeeding children, 1-4 y of age, with 3 d of dietary data and whose households had incomes < 130% of the poverty level were included in the study sample (n = 499). Nutrient adequacy ratios for each of 15 nutrients were the dependent variables in multiple regression models that controlled for the following: age, sex and ethnicity of the individual; income, size and location of the household; schooling of the household head; home ownership; school lunch and breakfast participation; and season in which the interview was conducted. WIC benefits positively influenced (P < 0. 05) the intakes of 10 nutrients. For iron and zinc, the average increase due to WIC represented 16.6 and 10.6%, respectively, of the preschooler recommended dietary allowance (RDA) for these nutrients. The same analyses of the Food Stamp Program revealed increases in five nutrients. For iron and zinc, the average increase due to Food Stamps represented 12.3 and 9.2%, respectively, of the preschooler RDA. The effects of the WIC Program on the intakes of iron and zinc were greater than that of cash income, and neither program affected the intakes of fat, saturated fat or cholesterol.

Adult↗
PubMed1998

Development of scales to measure psychosocial care needs of children with seizures and their parents. 1.

There is little research and no self-report assessment instruments available to guide nurses in the provision of psychosocial care to children with seizures and their families. Information on the development of two instruments, Report of Psychosocial Care Scale and Child Report of Psycyhosocial Care Scale, and their use in a research study to measure psychosocial care of children with new-onset seizures and their parents are presented in three parts. This first article describes development and initial testing of their psychometric properties. The second article, Part 2, "Psychosocial Care Needs of Parents of Children with New-Onset Seizures," describes results from the use of the parent scale with mothers and fathers of children with new-onset seizures. The third article, Part 3, "Psychosocial Care Needs of Children with New-Onset Seizures," reports findings from the use of the child scale with children ages 8-14 years with new-onset seizures.

Adaptation, Psychological↗
PubMed1998

Increasing prevalence of HIV antibody among blood donors monitored over 9 years in one blood bank.

To determine the time trend of HIV infection among non-professional blood donors at the Christian Medical College and Hospital, Vellore, the annual HIV prevalence among them for the years 1993-1997 was compared with that of the previous 5 yr. Since confirmed number of HIV positive blood donors is required for calculation of prevalence, the serum samples which were reactive for HIV 1/2 antibody by ELISA, were confirmed by Western blot. The annual prevalence of HIV antibody gradually increased from 1.6 per 1000 in 1988-1989, to 3.8 per 1000 in 1996-1997. The mean tri-annual prevalences for the years 1988-91, 1991-94 and 1994-97 were 1.3, 2.7 and 3.6 per 1000 respectively, suggesting a slow but steady increase in HIV prevalence over time. Our findings provide an insight into the dynamics of HIV infection in the general population of our country, whom the nonprofessional blood donors at our hospital represent.

Blood Banks↗
PubMed1997

Prospective case-control study of role of infection in patients who reconsult after initial antibiotic treatment for lower respiratory tract infection in primary care.

OBJECTIVE: To assess direct and indirect evidence of active infection which may benefit from further antibiotics in adults who reconsult within 4 weeks of initial antibiotic management of acute lower respiratory tract infection in primary care. DESIGN: Observational study with a nested case-control group. SETTING: Two suburban general practices in Arnold, Nottingham, over 7 winter months. SUBJECTS: 367 adults aged 16 years and over fulfilling a definition of lower respiratory tract infection and treated with antibiotics. 74 (20%) patients who reconsulted within 4 weeks for the same symptoms and 82 "control" patients who did not were investigated in detail at fallow up. MAIN OUTCOME MEASURES: Direct and indirect evidence of active infection at the time of the reconsultation or the follow up visit with the research nurse for the controls. Investigations performed included sputum culture, pneumococcal antigen detection, serial serology for viral and atypical pathogens and C reactive protein, throat swabs for detecting viral and atypical pathogens by culture and polymerase chain reaction, and chest radiographs. RESULTS: Demographic and clinical features of the groups were similar. Two thirds of the 74 patients who reconsulted received another antibiotic because the general practitioner suspected continuing infection. Any evidence of infection warranting antibiotic treatment was uncommon at reconsultation. The findings for the two groups were similar for the occurrence of identified pathogens; chest x ray changes of infection (present in 13%); and C reactive protein concentrations, which had nearly all fallen towards normal. Only three patients in the reconsultation group had concentrations > or = 40 mg/l. Pathogens identified at follow up in the 156 patients in both groups included ampicillin sensitive bacteria in six. Atypical infections diagnosed in 27 (Chlamydia pneumoniae in 22) and viral infections in 54 had probably been present at the initial presentation. CONCLUSION: Our study suggests that active infection, which may benefit from further antibiotics, is uncommon in patients who reconsult after a lower respiratory tract infection, and a repeat antibiotic prescription should be the exception rather than the rule. Other factors, such as patients' perception of their illness, may be more important than disease and infection in their decision to reconsult.

Adolescent↗
PubMed1997

Mental health. Heads and tales.

Interviews conducted by other users can be a successful means of capturing mental health users' views on services. In this study, more than a third of those with severe mental health problems considered themselves over-medicated, and many wanted more 'talking therapies'. More than three-quarters were satisfied with their community psychiatric nurse but under half were satisfied with their consultant. A fifth did not know how to get help in a crisis.

Community Mental Health Services↗
PubMed1997

Invasive infections due to a fish pathogen, Streptococcus iniae. S. iniae Study Group.

BACKGROUND: Streptococcus iniae is a pathogen in fish, capable of causing invasive disease and outbreaks in aquaculture farms. During the winter of 1995-1996 in the greater Toronto area there was a cluster of four cases of invasive S. iniae infection in people who had recently handled fresh, whole fish from such farms. METHODS: We conducted a prospective and retrospective community-based surveillance for cases of S. iniae infection in humans. To obtain a large sample of isolates, we studied cultures obtained from the surface of fish from aquaculture farms. Additional isolates were obtained from the brains of infected tilapia (oreochromis species). All the isolates were characterized by pulsed-field gel electrophoresis (PFGE). RESULTS: During one year, our surveillance identified a total of nine patients with invasive S. iniae infection (cellulitis of the hand in eight and endocarditis in one). All the patients had handled live or freshly killed fish, and eight had percutaneous injuries. Six of the nine fish were tilapia, which are commonly used in Asian cooking. Thirteen additional S. iniae isolates (2 from humans and 11 from infected tilapia) were obtained from normally sterile sites. The isolates from the nine patients were indistinguishable by PFGE and were highly related to the other clinical isolates. There was substantial genetic diversity among the 42 surveillance isolates from the surface of fish, but in 10 isolates the PFGE patterns were identical to those from the patients with S. iniae infection. CONCLUSIONS: S. iniae can produce invasive infection after skin injuries during the handling of fresh fish grown by aquaculture. We identified a clone of S. iniae that causes invasive disease in both humans and fish.

Adult↗
PubMed1997

Principles of an adaptive method for measuring the slope of the psychometric function.

Recent developments in the efficient estimation of threshold are here extended to the problem of how best to estimate the slope of the psychometric function. An adaptive method is described for selecting stimulus intensities that are optimal for slope estimation. A two-dimensional array of probabilities of different thresholds and slopes is used to calculate the stimulus intensity for the next trial; this array is updated after the trial, using Bayes' theorem to incorporate information from the subject's response. The practical implementation and efficiency of the method are demonstrated and discussed.

Bayes Theorem↗