Search PubMed⌕ Search

Biomedical subjects

C A Hart

Publications and source records attributed to C A Hart.

At least 109 records · Page 6Linked to original sources
PubMed2001

Selenium status, kwashiorkor and congestive heart failure.

UNLABELLED: Selenium deficiency is associated with congestive heart failure (CHF) in geographic areas where dietary selenium intake is low and in individuals receiving total parenteral nutrition. Among 66 children with kwashiorkor (including marasmic-kwashiorkor), those who developed CHF had lower serum selenium concentrations than those who did not (32.9 +/- 8.3 vs 41.1 +/- 11.9 microg/L, mean +/- SD, p = 0.03). This association was independent of serum albumin and selenium status was not associated with severity of symptoms, anthropometric indices or HIV infection. CONCLUSION: This association raises the possibility that selenium may contribute to CHF in washiorkor.

Child↗
PubMed2001

Hepatitis B prevalence and risk factors for HBsAg carriage amongst Somali households in Liverpool.

The prevalence of hepatitis B core antibody (anti-HBc) and surface antigen (HBsAg) in the Somali population in Liverpool is described and groups who may benefit from vaccination are identified. A cross-sectional descriptive study was undertaken. A total of 439 subjects, aged between 10 months and 80 years, from 151 households, were screened for anti-HBc and HBsAg. One hundred ninety-four (44.2%) were children aged less than 15 years. Three hundred and nine (69%) of enrolled subjects were born in Somalia, 122 (27.2%) were born in the UK and 8 were born elsewhere. Of the study population, 5.7% were carriers of HBsAg, with the highest prevalence in adults aged 20 to 44 years (9.4%). A history of circumcision (RR 95% CI; 1.2, 1.1-1.5) was the most significant risk factor for HBsAg carriage, but was not significant on multivariate analysis. Prevalence of anti-HBc was 27.5%, and increased with age over the first four decades. Univariate analysis showed that a history of living in a refugee camp (RR 95% CI; 3.1, 1.7-5.7), receiving an injection in Somalia (2.1, 1.7-2.5), a history of circumcision or other surgical procedure in Somalia (1.4, 1.3-1.6) and being born in Somalia (1.3, 1.2-1.4) were significant risk factors for anti-HBc positivity. On multivariate analysis, only circumcision (OR 95% CI; 4.3, 1.8-10.3) and receiving an injection in Somalia (2.5, 1.5-4.4) remained significant. Seven of 80 (8.7%) children born in the UK and aged five years or less had evidence of exposure to hepatitis B, of whom only one had a close family member identified to be HBsAg seropositive. Previous infection with hepatitis B is common in this population. Horizontal transmission may be continuing at an early age within the UK, suggesting a population of at risk individuals who would benefit from surveillance and immunisation. Community circumcision is a risk factor for hepatitis B transmission and best practice should be followed when this procedure is undertaken.

Adolescent↗
PubMed2000

Molecular and serologic characterization of novel serotype G8 human rotavirus strains detected in Blantyre, Malawi.

During a 2-year study of diarrhea among children in Blantyre, Malawi, greater than 50% of rotavirus strains genotyped by using reverse transcription-polymerase chain reaction possessed previously unrecognized combinations of the neutralization proteins VP7 and VP4. Serotype G8 rotaviruses, which have been identified recently in several African countries, were found to possess P[4] or P[6] VP4 genotype specificity. Two of these short electropherotype rotaviruses were further investigated: these comprised a P[6], G8 representative strain (MW23) and a P[4], G8 representative strain (MW333). The VP7 gene sequences of both strains exhibited greatest homology to human and animal serotype G8 rotaviruses. Sequence analysis of the VP4 gene of MW23 indicated closest identity to the P2A[6], G9 strain US1205 from the United States. The VP4 gene of MW333 was most closely related to the P[4], G12 strain L26 isolated in the Philippines and the Australian P[4], G2 strain RV-5. The NSP4 gene sequences of both strains were classified in NSP4 genetic group I. RNA-RNA hybridization demonstrated that each of these two strains is related to the DS-1 genogroup of human rotaviruses. Subgroup analysis and virus neutralization confirmed complete antigenic characterization of MW23 as subgroup I, P2A[6], G8 and MW333 as subgroup I, P1B[4], G8. The similarity of the VP7 gene sequences of the prototype strains described in this report to bovine serotype G8 rotaviruses suggests that they may represent human/bovine reassortant viruses.

Animals↗
PubMed2000

The role of RANTES in meningococcal disease.

The chemokine RANTES (regulated on activation, normal T cell expressed and secreted) is a potent regulator of leukocyte trafficking. RANTES preferentially attracts mature CD4 cells as well as macrophages and eosinophils, but not neutrophils. In total, 128 children with meningococcal disease were prospectively studied, and the role of RANTES in the pathophysiology of meningococcal disease was assessed. Plasma RANTES, interleukin (IL)-8, IL-6, IL-1 receptor agonist, and tumor necrosis factor-alpha were measured at admission. Severity of disease was stratified by the Glasgow meningococcal septicemia prognostic score (GMSPS). RANTES levels correlated significantly with IL-8 levels, admission lactate levels, platelets, prothrombin time, and activated partial thromboplastin time. RANTES levels were lower in children with severe disease (GMSPS>/=8; P=.001), in those with septic shock (P<.0005), and in nonsurvivors (P=.048; Mann-Whitney test). RANTES is a potential mediator in the pathophysiology of meningococcal disease.

Adolescent↗
PubMed2000

Detection of type III secretion system genes in animal isolates of Bordetella bronchiseptica.

A cosmid clone bank of Bordetella bronchiseptica genomic DNA was screened for the presence of type III secretion (TTS) genes using a probe derived from the TTS system genes of Ralstonia solanacearum. A 3.35kb PstI fragment, sub-cloned from a hybridising cosmid clone, was sequenced and found to contain a 97bp overlap with the previously reported B. bronchiseptica bscIJKLNO TTS gene cluster. DNA and predicted protein homology analysis suggests that a bscPQRST cluster lies immediately downstream of bscIJKLNO. A PCR amplification assay indicated that the bscT locus was present in 27 B. bronchiseptica animal isolates tested (100%). Dot-blot DNA hybridisation using probes for bscT and bscP confirmed the presence of these loci in six canine isolates associated with a variety of clinical signs. Although TTS has been implicated in the pathogenicity of B. bronchiseptica, it is likely that different clinical manifestations may be due to variations in gene expression or host factors, rather than the absence or presence of TTS genes.

Amino Acid Sequence↗
PubMed2000

Clinical presentation and outcome of Pneumocystis carinii pneumonia in Malawian children.

BACKGROUND: Necropsy studies from Africa have shown that Pneumocystis carinii pneumonia (PCP) is common in infants with HIV infection. We aimed to describe the rate, clinical presentation, and outcome of PCP in young Malawian children with acute severe pneumonia. METHODS: Children aged between 2 months and 5 years who were in hospital with a diagnosis of severe pneumonia were admitted to a study ward for clinical monitoring. We carried out blood culture, immunofluorescence on nasopharyngeal aspirate samples to test for PCP, polymerase chain reaction to detect HIV, and chest radiography. FINDINGS: 16 cases of PCP were identified among 150 children with radiologically confirmed severe pneumonia. All were HIV-positive and younger than 6 months. 21 children had bacterial pneumonia (including one who was also PCP positive) and 114 were not confirmed. The most common bacterial pathogens among children without PCP were Streptococcus pneumoniae (eight) and non-typhoidal salmonellae (seven). On admission, children with confirmed PCP had a lower mean age, body temperature, and oxygen saturation than children with bacterial pneumonia and were less likely to have a focal abnormality on auscultation. Oxygen requirements were much greater in children with PCP than those with bacterial pneumonias (96 of 105 hospital days vs 15 of 94, p<0.0001). Ten of 16 children with PCP and six of 21 with bacterial pneumonia died (relative risk 2.19 [95% CI 1.0-4.7]). The overall case-fatality rate of severe pneumonia was 22%. In addition to a strong association with PCP, a fatal outcome was significantly and independently associated with HIV infection (2.98 [1.1-7.9]) and with age under 6 months (2.76 [1.0-5.2]). INTERPRETATION: PCP is common and contributes to the high mortality from pneumonia in Malawian infants. Clinical features are helpful in diagnosis. The study highlights the impact of HIV infection and difficult issues of management in countries with few resources.

AIDS-Related Opportunistic Infections↗
PubMed2000

Antibiotic susceptibility of canine Bordetella bronchiseptica isolates.

The antimicrobial sensitivities of 78 recent (1995-1998) canine isolates of Bordetella bronchiseptica from 13 separate sources were determined. Minimum inhibitory concentrations were assessed using the E-test method or by agar dilution. All 78 isolates were sensitive to tetracycline, doxycycline, enrofloxacin, and amoxycillin/clavulanic acid; the majority were sensitive to ampicillin (63/78; 81%), trimethoprim (57/78; 73%), and sulphadiazine (63/78; 81%). Plasmids were detected in 14 out of the 24 isolates tested. There was no correlation between the presence of plasmids and antibiotic resistance, but there was some correlation between the presence of plasmids and the origin of the isolates. Three sizes of plasmid were found: 20, 14, and 5.5 kb. Eight of the isolates contained all three plasmids, the remainder one or two, Thirteen isolates demonstrated beta-haemolysis, of which six produced a soluble haemolysin. Except for one isolate, haemolysin production correlated with plasmid carriage. Pulsed-field gel electrophoresis showed that all except one isolate could be grouped in the same genotype. Within this genotype isolates could be divided into three subtypes, generally corresponding to their place of origin.

Amoxicillin-Potassium Clavulanate Combination↗
PubMed2000

Increasing microbiological confirmation and changing epidemiology of meningococcal disease on Merseyside, England.

OBJECTIVES: To determine, for the last 5 years in children on Merseyside with clinical meningococcal disease (MCD), the impact on diagnostic yield of newer bacteriologic methods; bacterial antigen detection (AD) and polymerase chain reaction (PCR). METHODS: Prospective data collection at Royal Liverpool Children's Hospital over two epochs: 1 September 1992 to 30 April 1994 (epoch A, n = 126) and 17 November 1997 to 15 September 1998 (epoch B, n = 85). RESULTS: Epoch A was compared with epoch B. Diagnosis was confirmed by detection of meningococci in 78 of 126 (61.9%) versus 64 of 85 (75.3%, P = 0.04), but with a significantly lower rate of positive blood and cerebrospinal fluid culture in the later epoch. The proportion of cases receiving penicillin pretreatment was unchanged at 32%, but the proportion undergoing lumbar puncture decreased significantly. Median ages were higher in epoch B: 1.7 years versus 2.49 years (P = 0.013, Mann-Whitney). There was a significant increase in the proportion of cases due to serogroup C (14/78 (18%) versus 30/64 (46.9%), P = 0.001). CONCLUSIONS: Culture detection of meningococci from children with MCD has reduced, as less lumbar punctures are done. However, improved diagnosis by PCR and AD has increased microbiological confirmation overall. Serogroup C disease and the median age of cases continue to rise.

Adolescent↗
PubMed2000

A study of feline upper respiratory tract disease with reference to prevalence and risk factors for infection with feline calicivirus and feline herpesvirus.

A cross-sectional survey of a convenience sample of cats was carried out to determine the prevalence of and risk factors for respiratory tract disease, feline calicivirus (FCV) infection and feline herpesvirus (FHV) infection. Seven hundred and forty cats were studied; samples for isolation of FCV and FHV were obtained from 622 (84%). Data on individual cat and household variables were obtained by questionnaire for each cat and analysed using univariable and logistic regression analysis. Thirty-eight percent (282/740) of cats surveyed had respiratory tract disease. Eighteen of 24 predictor variables were found to be significantly (P<0.05) associated with the presence of respiratory tract disease in a cat on univariable analysis. Following logistic regression, several factors retained significance including isolation of FCV and FHV, younger cats (4-11 months of age) and multiple cat households. A negative association was found with breeding catteries and other types of household in comparison with rescue catteries. Overall, feline calicivirus was isolated from 162/622 (26%) of cats sampled; 33% of the cats with respiratory tract disease were FCV positive compared to 21% of healthy cats. Variables significantly associated with FCV isolation on logistic regression were the presence of respiratory tract disease and contact with dogs with and without respiratory tract disease. Feline herpesvirus was isolated from 30/622 (5%) of all cats sampled; 11% of cats with respiratory tract disease were FHV positive compared to 1% of healthy cats. Variables significantly associated with FHV isolation on univariable analysis included age, gender, and the presence of respiratory tract disease. Vaccination showed a negative association. Logistic regression analysis of the data for FHV was limited by the sample size and the low prevalence of FHV.

Age Factors↗
PubMed2000

Plasma urea appearance rate is lower when children with kwashiorkor and infection are fed egg white-tryptophan rather than milk protein.

In kwashiorkor, there is less endogenous proteolysis in response to acute infection than in a well-nourished state. Thus the amino acid composition of dietary protein may be more important in facilitating the acute phase response in kwashiorkor. This study tested the hypothesis that during the treatment of kwashiorkor with infection, there is a lower rate of urea appearance when the dietary intake of amino acids more closely resembles the amino acid composition of acute phase proteins. Thirty children in Malawi with kwashiorkor and acute infection were fed isoenergetic, isonitrogenous meals containing either egg white-tryptophan or milk as a protein source. After 24 h, the rates of urea appearance and whole-body protein breakdown and synthesis were measured with the use of 1-13C-leucine and 15N2-urea tracers. Plasma concentrations of seven acute phase proteins, interleukin 6 and tumor necrosis factor-alpha were measured on admission, and at 24 and 48 h. The 16 children who received egg white-tryptophan had lower rates of urea appearance than those who received milk [57+/-30 vs. 87+/-36 micromol/(kg x h), mean +/- SD, P<0.02]. No significant differences were found in the rates of whole-body protein turnover or in the concentration of any of the acute phase proteins or cytokines. The concentration of interleukin 6 was consistent with an appropriate proinflammatory response and correlated directly with the concentrations of C-reactive protein (r = 0.67, P<0.01) and alpha1-antitrypsin (r = 0.40, P<0.05). The findings suggest that egg white-tryptophan is associated with less amino acid oxidation in kwashiorkor and acute infection than is milk.

Acute-Phase Proteins↗
PubMed2000

Tropical and exotic infections. Proceedings of the 5th Liverpool Tropical School Bayer Symposium on Microbial Diseases. 14 February 1998.

In summary, MDR strains of S. typhi are both epidemic and endemic in many countries in Asia and MDR S. paratyphi A has recently emerged in Pakistan. Multiple clones may be present in a given area at any time. Fluoroquinolones and third generation cephalosporins have been used widely over the past decade to treat MDR strains. The clinical superiority of fluoroquinolones is now threatened by the rapid emergence of chromosomally mediated resistance and cephalosporin resistance is also being reported. Whether these problems can be overcome by the use of newer fluoroquinolones or cephalosporins remains to be seen. Meanwhile, furazolidone and azithromycin deserve further trials, and clinical and molecular surveillance of resistance patterns remains essential.

Cholera↗
PubMed2000

Infections in AIDS.

Explore the source record for details and available documents.

AIDS-Related Opportunistic Infections↗
PubMed2000

Hantaviruses.

Since the recognition of the hantavirus pulmonary syndrome (HPS) in the USA in 1993, interest in hantavirus diseases has intensified worldwide. It is clear that hantaviruses have been historically responsible for a variety of human illnesses. Hantaviruses form a separate genus within the Bunyaviridae family. There are currently >20 recognised sero/genotypes and many others are under investigation. Each hantavirus type appears to be specific to a different rodent host. Virus phylogeny very closely reflects rodent phylogeny. The different hantavirus types are associated with different types of disease both in terms of target organs and disease severity. Two major diseases are recognised: haemorrhagic fever with renal syndrome (HFRS) and HPS. HFRS is primarily a disease of the old world while HPS is only recognised in the Americas. Over the past few decades the understanding and recognition of hantavirus disease throughout the world have greatly expanded. The number of recognised virus types continues to grow, as does the spectrum of hantavirus disease. There is evidence of hantavirus causing human disease in the British Isles, but at present it remains a largely uncharacterised disease.

Animals↗
PubMed2000

Genotypes of multidrug-resistant Salmonella enterica serotype typhimurium from two regions of Kenya.

A combination of phage typing and pulsed-field gel electrophoresis of Xbal-digested chromosomal DNA has been used to study the epidemiological relationships of multidrug-resistant Salmonella enterica serotype typhimurium from Nairobi (64 isolates) and Kilifi (40 isolates) collected over the period 1994-1997. Isolates from Nairobi belonged to 11 definitive phage types (DTs) encompassing eight different PFGE patterns. In contrast, isolates from Kilifi were mainly DT 56 (60%) and all fell into a single PFGE pattern. The remaining isolates did not conform to a recognisable phage type. We conclude that multidrug-resistant S. typhimurium infections from Nairobi were caused by multiple strains while those from Kilifi were likely to be from a microepidemic caused by a single clone.

Adult↗
PubMed2000

Analysis of plasmid and chromosomal DNA of multidrug-resistant Salmonella enterica serovar typhi from Asia.

Molecular analysis of chromosomal DNA from 193 multidrug-resistant (MDR) Salmonella enterica serovar Typhi isolates from 1990 to 1995 from Pakistan, Kuwait, Malaysia, Bangladesh, and India produced a total of five major different pulsed-field gel electrophoresis (PFGE) patterns. Even within a particular country MDR S. enterica serovar Typhi DNA was found to be in different PFGE groups. Similar self-transferable 98-MDa plasmids belonging to either incompatibility group incHI1 or incHI1/FIIA were implicated in the MDR phenotype in S. enterica serovar Typhi isolates from all the locations except Quetta, Pakistan, where the majority were of incFIA. A total of five different PFGE genotypes with six different plasmids, based on incompatibility and restriction endonuclease analysis groups, were found among these MDR S. enterica serovar Typhi isolates.

Anti-Bacterial Agents↗