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R Morris

Publications and source records attributed to R Morris.

At least 73 records · Page 4Linked to original sources
PubMed2000

Long-term clinical and neurophysiological follow-up of patients with peripheral, neuropathy associated with benign monoclonal gammopathy.

The incidence of hematological malignancy in patients with monoclonal gammopathy of undetermined significance (MGUS) has been assessed as 17% to 25%. To ascertain whether this is true of neuropathy associated with MGUS, a long-term (5-42 years) retrospective clinical and neurophysiological follow-up was conducted in 50 cases (immunoglobulin M [IgM], n = 38; IgG, n = 11; IgA, n = 1). Only three patients developed hematological malignancy. Of 25 survivors with IgM paraproteinemia, 7 had myelin-associated glycoprotein antibodies with typical clinical features. Evoked distal muscle amplitudes were significantly smaller than for the other paraprotein classes. Preferential distal demyelination manifested by relative prolongation of distal motor latency was not apparent in the cases of long duration. Two patients with IgM antidisialosyl antibodies and cold agglutinating activity had a large fiber neuropathy with intermittent oculofacial involvement. Both responded to intravenous immunoglobulin. Findings in the remaining patients were varied. Recognition of IgM subgroups is important both for prognosis and possible response to treatment.

Adult↗
PubMed2000

Relationship between classic risk factors, plasma antioxidants and indicators of oxidant stress in angina pectoris (AP) in Tehran.

Cardiovascular disease (CVD) in general seems to be the leading cause of death in the Eastern Mediterranean Region (EMR) including Iran. This may be due to classic risk factors such as high triglyceride (TG), high total cholesterol (TC), and low levels of high density lipoprotein cholesterol (HDL-C). The impact of antioxidants as potentially protective risk factors against early coronary heart disease (CHD) is unknown in Iran. Therefore, relationships between angina and plasma antioxidants and indicators of lipid peroxidation were investigated in a case-control study. In this study, 82 cases of previously undiagnosed angina pectoris (AP), identified by a modified WHO Rose chest pain questionnaire and verified by electrocardiography during treadmill exercise testing, were compared with 146 controls selected from the same population of over 4000 male civil servants aged 40-60 years. Subjects with AP declared significantly less physical activity and had higher serum TG [means (S.E.M.) 2.32 (0.18) versus 1.61 (0.07) mmol/l] but lower HDL-C [1.01 (0.04) versus 1.18 (0.03) mmol/l] than age-matched controls. Levels of total serum cholesterol, low-density lipoprotein cholesterol (LDL-C) and lipoprotein(a) [Lp(a)] were not significantly different between the two groups, while the ratio of LDL-C/HDL-C was significantly higher [4.51 (0.23) versus 3.54 (0. 11)] for subjects with AP than for the controls. There was no significant difference in plasma levels of alpha-tocopherol, vitamin C, alpha- and beta-carotene. However, retinol [1.90 (0.06) versus 2. 09 (0.05)] and beta-cryptoxanthin [0.398 (0.04) versus 0.467 (0.03)] were significantly lower in AP. Furthermore, angina cases exhibited a higher index of lipid peroxidation than controls (e.g. malondialdehyde, MDA; 0.376 (0.010) versus 0.337 (0.009) micromol/l). On multiple logistic regression analysis, retinol with odds ratio (OR) of 0.644 [95% confidence interval (CI; 0.425-0.978)], beta-cryptoxanthin, with an OR of 0.675 (CI; 0.487-0.940), oxidation indices, MDA with OR of 1.612 (95% CI; 1.119-2.322) and LDL-C/HDL-C ratio with OR of 2.006 (95% CI; 1.416-2.849) showed the most significant independent associations with AP in this group of Iranians. In conclusion, the state of lipid peroxidation as well as the status of special antioxidants may be co-determinants of AP in Iran, in parallel with the influence of classical risk factors for cardiovascular disease.

Adult↗
PubMed2000

Spinal lamina I neurons that express neurokinin 1 receptors: morphological analysis.

The morphology of neurons in lamina I of the dorsal horn of the lumbar spinal cord which express neurokinin 1 receptors in the rat has been investigated. On the basis of soma and dendritic measurements, these neurons form two populations. One group consists of large neurons that stain intensely for the neurokinin 1 receptor with the immunochemical methods employed. They have a large soma, typically giving rise to between three and five thick principal dendrites. The dendritic tree, however, is relatively sparse, with the principal dendrites giving rise to small numbers of second- and third-order branches. All these dendrites are almost spine free. The dendritic tree spreads extensively in the rostrocaudal (approximately 550microm) and mediolateral (approximately 30microm) orientations, with few ventrally directed branches. These cells give rise to a single axon from their soma or a principal dendrite that generates a few local branches and also ramifies sparsely in deeper laminae (II-IV). The details of axonal morphology were established from intracellularly labelled material. Ultrastructural analysis of the synaptic input to these neurons reveals that they receive synapses with both clear round, flattened and dense-core vesicles; however, they do not form components of glomerular synapses. The second neuron type stains less intensely and typically has a small fusiform soma, giving rise to dendrites at its rostral and caudal poles. The dendritic tree is long in the rostrocaudal orientation (approximately 350microm), but restricted mediolaterally (approximately 40microm). The primary dendrites of these neurons bifurcate and soon give rise to third-order branches that are spiny. No pattern of organization could be detected for the distribution of either neuron type. These observations are discussed in the light of other recent studies indicating a central role for lamina I neurons expressing neurokinin 1 in the perception of severe pain.

Aging↗
PubMed2000

A secondary school outbreak of mumps following the childhood immunization programme in England and Wales.

Since the introduction of routine measles, mumps and rubella immunization for children in England and Wales in 1988, the incidence of mumps has declined steadily. We describe an outbreak of mumps in 1996 attacking 34 of a cohort of 98 schoolchildren born in 1982 and 1983. This is the largest outbreak in the UK since the introduction of the vaccine into the childhood immunization schedule. Salivary IgM assay was used as a simple, minimally invasive test to confirm the diagnosis. The occurrence of the outbreak demonstrates that British children who were just too old to receive mumps immunization in 1988 continue to be at risk of this disease as a result of diminished natural exposure. Further cases and outbreaks in this cohort are to be expected. Cohorts born before 1982 appear to be at less risk, presumably because of naturally acquired infection before the introduction of immunization.

Adolescent↗
PubMed2000

Invasive Haemophilus influenzae disease in adults.

We reviewed retrospectively all invasive Haemophilus influenzae (Hi) infections in adults ascertained from reference laboratory records and notifications from five NHS regions over the 5 years from 1 October 1990, a period encompassing the introduction of routine Hib childhood immunization (October 1992). A total of 446 cases were identified, a rate of 0.73 infections per 10(5) adults per annum. Though numbers of Hib infections in adults fell after the introduction of Hib vaccines for children (P = 0.035), and there was no increase in infections caused by other capsulated Hi serotypes, total numbers of invasive Hi infections increased due to a large rise in infections caused by non-capsulated Hi (ncHi) strains (P = 0.0067). There was an unexpectedly low rate of infections in those aged 75 years or more (P < 0.0001). The commonest clinical presentations were pneumonia with bacteraemia (227/350, 65%) and bacteraemia alone (62/350, 18%) and the highest rates of disease were in the 65-74 years age group (P < 0.0001). Clinical presentation was not influenced by the capsulation status of the invading Hi strain. 103/350 cases (29%) died within 1 month, and 207/350 (59%) within 6 months of their Hi infection. Case fatality rates were high in all age groups. Pre-existing diseases were noted in 220/350 cases and were associated with a higher case fatality rate (82% vs. 21%, P < 0.0001). After the introduction of Hib immunization in children, invasive Hib infections in unimmunized adults also declined, but the overall rate of invasive Hi disease in adults increased, with most infections now caused by non-capsulated strains. Physicians and microbiologists should be aware of the changing epidemiology, the high associated mortality and high risk of underlying disease. Invasive haemophilus infections in adults should be investigated and treated aggressively.

Adult↗
PubMed2000

Induction of immunological memory in UK infants by a meningococcal A/C conjugate vaccine.

The induction of immunological memory to serogroup A and C polysaccharides in UK infants immunized with three doses of a meningococcal A/C oligosaccharide CRM197 conjugate vaccine was investigated. Forty UK infants vaccinated previously with three doses of a meningococcal A/C oligosaccharide-CRM197 conjugate vaccine at 2, 3 and 4 months of age, were revaccinated at a mean age of 145.6 weeks with either a 10 or 50 microg dose of licensed meningococcal A/C polysaccharide vaccine. Serogroup-specific antibody and serum bactericidal antibody (SBA) responses were measured by enzyme-linked immunosorbent assay and serum bactericidal assays, respectively. Following challenge, anti-serogroup A and C polysaccharide antibody levels rose from pre-booster geometric mean concentrations (GMC) of 3.1 and 2.1 microg/ml respectively to 19.6 and 21.0 microg/ml 1 month post-booster. Serum bactericidal antibody geometric mean titres (GMTs) for serogroups A and C increased 156- and 113-fold from 2.1 and 7.1 pre-booster respectively to 327.4 and 800.7 post-booster. A serogroup A control group of 45 children received a 10 microg dose of licensed meningococcal A/C polysaccharide vaccine (with no prior history of serogroup A vaccination) had serogroup A SBA GMTs of 2.3 pre-vaccination rising to 8 post-vaccination with corresponding GMCs of 0.8 and 10.8 microg/ml. These rises in SBA following serogroup A/C conjugate vaccination are indicative of immunological priming.

Antibodies, Bacterial↗
PubMed2000

Cardiac dysfunction occurs in the HIV-1 transgenic mouse treated with zidovudine.

Cardiomyopathy in AIDS is an increasingly important clinical problem. Mechanisms of AIDS cardiomyopathy were explored using AIDS transgenic mice that express replication-incompetent HIV-1 (NL4-3delta gag/pol). Transgenic and FVB/n mice (n = 3 to 6 per cohort) received water ad libitum with and without zidovudine (3'-azido-2',3'-deoxythymidine; AZT; 0.7 mg/ml) for 21 or 35 days. After 21 days, echocardiographic studies were performed and abundance of mRNA for cardiac sarcoplasmic reticulum calcium ATPase (SERCA2), sodium calcium exchanger (NCX1), and atrial natriuretic factor were determined individually using Northern analysis of extracts of left ventricles. After 35 days, contractile function and relaxation were analyzed in isolated work-performing hearts. Histopathological and ultrastructural (transmission electron microscopy) changes were identified. After 21 days, molecular indicators of cardiac dysfunction were found. Depressed SERCA2 and increased atrial natriuretic factor mRNA abundance occurred in left ventricles from AZT-treated transgenic mice. NCX1 abundance was unchanged. Eccentric left ventricle hypertrophy was determined echocardiographically. After 35 days, cardiac dysfunction was worst in AZT-treated and AZT-untreated transgenic mice. Decreases in the first derivative of the maximal change in left ventricle systolic pressure with respect to time (+dP/dt) occurred in transgenic mice with and without AZT. Increased half-time of relaxation and ventricular relaxation (-dP/dt) occurred in AZT-treated and -untreated transgenic mice. Increased time to peak pressure was found only in AZT-treated transgenic mice. In AZT-treated FVB/n mice, -dP/dt was decreased. Ultrastructurally, mitochondrial destruction was most pronounced in AZT-treated transgenic mice, but also was found in AZT-treated FVB/n mice. Transgenic mice that express HIV-1 demonstrate cardiac dysfunction. AZT treatment of FVB/n mice causes mitochondrial ultrastructural alterations that are similar to those in other species. In transgenic mice, AZT treatment worsens molecular and ultrastructural features of cardiomyopathy. HIV-1 constructs and AZT each contribute to cardiac dysfunction in this murine model of AIDS cardiomyopathy.

Acquired Immunodeficiency Syndrome↗
PubMed2000

Expression of neuropeptide Y and neuropeptide Y Y1 receptors and neuronal markers following axotomy in the rat spinal cord and gracile nucleus.

Using immunocytochemistry, the effects of denervation on the expressions of the neuropeptide Y Y1 receptor, neuropeptide Y and neuronal markers were investigated in the lumbar spinal cord of the rat. Ten, 17 and 24 days after unilateral sciatic nerve section, the distribution of the neuropeptide Y Y1 receptor was seen in lamina II in the ipsilateral and contralateral side of the lumbar spinal cord and gracile nucleus, whereas neuropeptide Y immunoreactivity located strongly in laminae I-II and moderately in laminae III-IV in the ipsilateral side. Denervation, following section of the sciatic nerve, resulted in no change in the distribution of the neuropeptide Y Y1 receptor in the spinal cord. This suggests that the neuropeptide Y that is expressed in myelinated afferents following nerve section does not affect the expression of this receptor. This is particularly apparent in the gracile nucleus which shows clear neuropeptide Y staining following sciatic nerve section and no expression of the neuropeptide Y Y1 receptor.

Animals↗
PubMed2000

Comparison of localization of the neurokinin 1 receptor and nitric oxide synthase with calbindin D labelling in the rat spinal cord.

A comparison of the localization of the neurokinin 1 (NK1) receptor and nitric oxide synthase with calbindin D labelling in the lumbar spinal cord was carried out in the rat using immunocytochemistry. Considerable regional variations were observed. Application of the antibody to calbindin D resulted in dense staining in laminae I and II and light staining in the other laminae. Occasional scattered cells were seen in the deep laminae and in the lamina X, the ventral horn and the lateral spinal nucleus. The results indicate that neurones expressing calbindin D, NK1 receptor and NOS are three separate populations in the dorsal horn of the lumbar spinal cord.

Animals↗
PubMed2000

Comparison of localization of the neurokinin 1 receptor with AMPA-type glutamate receptors in the rat spinal cord.

With the cloning of the alpha-amino-3-hydroxy-5-methyl-4-isaxole propionic acid (AMPA)-type receptor subunits, it is now possible to localize these receptor subunits in the spinal cord. Comparison of the neurokinin 1 receptor distribution with that of non-N-methyl-D-aspartate glutamate receptor subunits (GluR1-4), considered to be AMPA-type, was investigated in rat spinal cord by immunocytochemical methods. Different patterns of immunolabelling were observed with the antibodies to the GluR1, GluR2/3 and GluR4 subunits in the lumbar spinal cord. Immunolabelling with antibodies to both GluR1 and GluR2/3 revealed intensive staining in the dorsal horn, while staining for GluR2/3 and GluR4 was dense in the motor neurons of the ventral horn. These results suggest that in the rat spinal cord AMPA-type receptors vary their composition according to the region where they are expressed. Neurokinin-1-receptor-expressing neurons in the dorsal horn do not appear to express the GluR4 subunit, however, whether they express the GluR1, GluR2/3 receptors subunits could not be determined.

Animals↗
PubMed2000

Early predictors of mortality in pneumococcal bacteraemia.

OBJECTIVES: Pneumococcal bacteraemia carries a mortality of about 20%. Approximately 50% of deaths from pneumococcal bacteraemia occur within the first 48 h of admission. In order to influence outcome, critically ill patients should be identified at the time of presentation. This study enables the clinician to rapidly make an evidence-based assessment of a patient's prognosis, allowing the identification of patients who should be placed in a high-risk category at an early stage, when appropriate management is most likely to be effective. METHODS: Data were collected from the medical record of history, physical examination, radiological examination and laboratory investigations done on initial presentation using a standardized proforma. The data were first examined by Pearson's Chi-squared test, with Yates' correction if needed. Variables found to be significantly associated with case fatality ( P < 0.05) by these methods were examined by stepwise logistic regression analysis in order to identify those factors which were independent predictors of case fatality. RESULTS: The overall case fatality was 21%. Older age, apyrexia, tachypnoea, bilateral consolidation, hypoalbuminaemia, elevated aminotransferases, renal impairment, acidosis and leucopaenia were significantly associated with higher case fatality. Older age, acidosis and elevated serum alanine aminotransferase (ALT) were independent predictors of case fatality. Fifty-five percent of isolates belonged to serotypes 4, 6B, 9V, 14, 19F and 23F, to which good antibody levels have been documented in both young and elderly patients post-vaccination. Serotype 14 was most common, and was significantly associated with higher case fatality. Colder weather was associated with a higher incidence of both infection and case fatality. The case fatality amongst patients receiving ITU management was 44%. Less than 50% of patients who died received ITU management. CONCLUSIONS: Despite the increased availability of new antibiotics and vaccines, the mortality of patients with pneumococcal bacteraemia remains unchanged. The parameters above allow early identification of patients with a higher case fatality; these patients may benefit from being placed in a "high-risk" category early on in their management. Vaccination of the elderly may reduce the incidence and/or mortality from pneumococcal bacteraemia. Further studies are required to understand the reasons for referral for intensive therapy in acute pneumococcal bacteraemia and whether ITU management affects outcome.

Acidosis↗
PubMed2000

Guidance for the performance evaluation of three-dimensional air quality modeling systems for particulate matter and visibility.

Guidance for the performance evaluation of three-dimensional air quality modeling systems for particulate matter and visibility is presented. Four levels are considered: operational, diagnostic, mechanistic, and probabilistic evaluations. First, a comprehensive model evaluation should be conducted in at least two distinct geographical locations and for several meteorological episodes. Next, streamlined evaluations can be conducted for other similar applications if the comprehensive evaluation is deemed satisfactory. In all cases, the operational evaluation alone is insufficient, and some diagnostic evaluation must always be carried out. Recommendations are provided for designing field measurement programs that can provide the data needed for such model performance evaluations.

Air Pollution↗
PubMed2000

Immunogenicity and reactogenicity of a pneumococcal conjugate vaccine administered combined with a haemophilus influenzae type B conjugate vaccine in United Kingdom infants.

BACKGROUND: Streptococcus pneumoniae is a major disease burden in young children and the incidence of antibiotic-resistant pneumococcal strains is increasing. Multivalent pneumococcal saccharide-protein conjugate vaccines have recently been developed. OBJECTIVES: To assess the immunogenicity and reactogenicity of a 7-valent pneumococcal conjugate vaccine (7VPnC) administered as a separate injection or as a combined injection with Haemophilus influenzae type b vaccine (HbOC) at 2, 3 and 4 months of age. METHODS: Randomized controlled trial of 368 healthy UK infants receiving routine vaccines only (control group), routine vaccines and 7VPnC as a separate injection (separate group), or routine vaccines and 7VPnC combined with HbOC (combined group) at 2, 3 and 4 months. The control group received 7VPnC at 5, 6 and 7 months. All groups received pneumococcal polysaccharide vaccine at 13 to 16 months. Anticapsular IgG antibodies to 7VPnC serotypes were measured at 2, 5, 13 and 14 months and safety data collected. RESULTS: IgG antibody concentrations at 5 months were higher in the two treatment groups compared with the controls for all 7VPnC serotypes (P < 0.001) and higher in the separate group than the combined group for five 7VPnC serotypes (P < 0.05). For both treatment groups antibody concentrations were higher at 14 months (range, 6.6 to 25.3 microg/ml) than at 5 months (range, 0.6 to 2.5 microg/ml) for all 7VPnC serotypes (P < 0.001). CONCLUSION: 7VPnC was well-tolerated, safe and immunogenic when administered as a separate or as a combined 7VPnC/HbOC injection. Although antibody responses were lower in the infants who received the combination compared with those who received 7VPnC as a separate injection, marked anamnestic responses to polysaccharide challenge were observed, suggesting that both groups were immunologically primed.

Antibody Formation↗
PubMed2000

The Immunization Monitoring Program Active (IMPACT) prospective five year study of Canadian children hospitalized for chickenpox or an associated complication.

BACKGROUND: Varicella vaccine was approved for use in Canada in 1998. A major goal of universal varicella vaccine programs is to reduce severe infection and associated complications. Baseline data are essential against which to judge the effectiveness of routine childhood immunization. OBJECTIVE: To describe morbidity and mortality among children hospitalized for chickenpox. Methods. From January 1, 1991, to March 31, 1996, chickenpox admissions to 11 pediatric referral centers were actively identified. Patient and illness characteristics were compared for 3 subgroups defined by prior health: healthy; unhealthy but immunocompetent; immunocompromised. RESULTS: Of 861 cases 488 (56.7%) were healthy, 75(8.7%) were unhealthy and 298 (34.6%) were immunocompromised. The immunocompromised children differed from healthy/unhealthy cases in mean age (6.4 vs. 4.0/4.6 years, respectively, P < 0.0001); median interval from rash onset to admission (2 vs. 5/5 days, P < 0.0001); complication rate (20% vs. 90%/79%; P = 0.001); and rate of acyclovir therapy (98% vs. 24%/39%; P = 0.001). Unhealthy vs. healthy cases had a higher frequency (P < 0.01) of intensive care (13.3% vs. 4.7%), ventilation (9.3% vs. 2.0%) and death (4% vs. 0.2%). CONCLUSION: These data provide a baseline for morbidity/mortality resulting from chickenpox before varicella vaccine use in Canada.

Adolescent↗
PubMed2000

Predicting early mortality following percutaneous stent insertion for malignant biliary obstruction: a multivariate risk factor analysis.

BACKGROUND: Percutaneous stent placement is an accepted method of palliation in malignant biliary obstruction. Factors predicting early mortality after this procedure have not been identified. METHODS: We performed a retrospective study of 141 patients with malignant biliary obstruction who underwent percutaneous stent placement for biliary decompression to identify the risk factors associated with early mortality (< or = 30 days). RESULTS: Of 14 clinicopathological and laboratory variables analysed blood urea, albumin, haemoglobin and alkaline phosphatase were found to be significant on univariate analysis. The age and gender of the patient along with cancer type, level of obstruction, presence of pyrexia and bilirubin level had no influence on early mortality. Stepwise logistic regression identified the haemoglobin level and blood urea to be independently significant in predicting early mortality. Overall 30-day mortality was 20.5% (29/141). Patients with blood urea over 4.3 mmol/l and a haemoglobin less than 10.9 g/dl had a mortality rate of 52% (12/23) compared with 14% (17/118) in the remainder. Using these two variables a regression equation has been derived which allows calculation of the probability of survival at 30 days after the percutaneous procedure. CONCLUSIONS: Laboratory variables in patients with malignant obstructive jaundice can be used to predict mortality following percutaneous stent insertion.

Adult↗