PubMed Health⌕ Search

Biomedical subjects

B A Schroeder

Publications and source records attributed to B A Schroeder.

At least 19 recordsLinked to original sources
PubMed2002

Subacute measles encephalitis in an immunocompetent adult.

Subacute sclerosing panencephalitis (SSPE) and subacute measles encephalitis (SME) are both rare complications of measles virus infection. SSPE typically affects immunocompetent children, has an insidious onset and follows a steadily progressive course. SME mainly occurs in immunosuppressed children and has a rapidly progressive course. We describe a 43 year old immunocompetent man who presented with a rapidly progressive fatal encephalopathy. Histological examination of the brain showed a meningoencephalitis with inclusion bodies. Complement fixing antibody to measles virus was present in his serum and CSF. Measles virus RNA was found in the brain, spinal cord and eye, but not in the CSF. Analysis of the nucleoprotein gene isolated from this patient did not show similarity to SSPE strains of the measles virus. This patient demonstrates that subacute encephalitis secondary to measles virus infection can develop in an immunocompetent adult host.

Adult↗
PubMed2001

Detection and characterisation of swine hepatitis E virus in New Zealand.

The objectives of the present study were to establish the presence of hepatitis E virus (HEV) in New Zealand pigs, first by testing for HEV antibody in pig herds throughout New Zealand to measure the herd prevalence, then by attempting to amplify HEV genomic sequences by PCR. Antibody was measured by two independently designed ELISA serology tests. HEV RNA fragments were amplified by RT-PCR of nucleic acid extracted from faeces of 10-12-week-old piglets using primers targeting ORF1, ORF2, and ORF2/3. PCR products were subject to phylogenetic analysis. Antibody to HEV was found throughout New Zealand pig herds as well as in the different age groups within the herds. Twenty herds from 22 tested were positive for HEV antibody (91% herd prevalence). Phylogenetic analysis of the amplified sequences placed this New Zealand strain of HEV closest to the human European strain It-1 (AF 110390) and U.S. swine strain (AF 082843) with 88% and 83% similarity respectively in ORF1. It was concluded that HEV is widely distributed in the New Zealand pig population. Phylogenetic analysis shows that this is a new HEV strain, grouping most closely with the United States/European cluster, which includes HEV strains of both human and swine origin.

Animals↗
PubMed2000

Prevalence and phylogenetic characterisation of TT-virus in the blood donor population of Auckland, New Zealand.

TT-virus (TTV, patient initials: T.T.), a novel DNA virus, was first isolated in Japan in 1997 from serum of a patient with post-transfusion hepatitis of unknown aetiology. To date, the contribution of TTV to liver disease remains doubtful. The potential for transmission via blood and blood products makes it essential to establish the prevalence of TTV viraemia in the blood donor population. 413 blood donor serum samples were chosen randomly, the DNA was extracted and TTV-specific DNA amplified by nested polymerase chain reaction (PCR). TTV infection was present in 13 out of 413 (3.15%) blood donors in the Auckland region of New Zealand using a set of primers targeting open reading frame (ORF) 1. These 13 amplification products (264 bp) were sequenced and TTV genotypes determined. Alignment with published TTV sequences showed that seven (53.8%) of the thirteen positive serum samples belonged to genotype 1, five (38.5%) belonged to genotype 2 and one (7.7%) could not be classified as either genotype 1 or 2. One hundred twenty-seven blood donor serum samples were retested with a second set of primers targeting the 5' region of the TTV genome in a single round PCR. Forty-three samples were positive for TTV DNA with these primers resulting in a prevalence of 37%. The data demonstrate that TTV is present among New Zealand blood donors and support the need for further investigation into the natural history of TTV infection.

Blood Donors↗
PubMed1996

Evaluation of alpha interferon for the treatment of chronic hepatitis B infection in Christchurch.

AIM: To evaluate alpha interferon for the treatment of chronic replicative hepatitis B infection in Christchurch patients. METHODS: Ten patients were divided into two groups depending upon whether their average pretreatment ALT levels were greater than twice the upper limit of normal (group 1, 6 subjects) or less than twice the upper limit of normal (group 2, 4 subjects). Interferon alpha-2a (4.5 mega units) was administered three times a week for 24 weeks with the addition of a preceding priming course of prednisone in group 2. RESULTS: At 6 months post treatment only one patient in group 1 had seroconverted (HBeAg to anti-HBe), however, the remaining five patients seroconverted from 18-32 months after therapy. This response was associated with normalisation of the transaminases and in 5/6 subjects a fall in the HBV DNA levels. In group 2 one subject seroconverted by 6 months despite a shortened course of Interferon. A delayed seroconversion (18 months) was observed in one patient and another had a partial response with the development of anti-HBe but associated with persistence of HBeAg. The remaining patient has not responded. CONCLUSIONS: Interferon alpha-2a was effective in promoting a seroconversion HBeAg to anti-HBe in patients with chronic hepatitis B and transaminases elevated to twice the upper limit of normal, although in most cases this response was delayed. Larger studies will be required to determine the role of steroid priming in those with less active disease.

Adult↗
PubMed1990

Specific sequence amplification of bovine viral diarrhoea virus nucleic acid.

Bovine viral diarrhoea virus (BVDV) causes infection of cattle worldwide and is a common contaminant of cell cultures in the laboratory. Methods of diagnosis for BVDV are time-consuming and inconsistent. We describe the development of an in vitro test based on enzymatic DNA amplification with Thermus aquaticus DNA polymerase of sequences of BVDV cDNA reverse transcribed from viral RNA. Specific sequences were amplified from infected cell cultures and clinical material using laboratory and field strains of BVDV including both cytopathic and non-cytopathic isolates. Both plus and minus strands of viral RNA can act as suitable templates for cDNA synthesis prior to sequence amplification. Internal restriction digest of amplified sequences and the co-amplification of multiple sequences increased the specificity of the reaction. The significance of the technique in relation to the diagnosis and understanding of strain differences is also discussed.

Animals↗
PubMed1989

The gastric bubble: roentgen observations.

The appearance of the stomach bubble provides many clues to underlying thoracoabdominal disorders. Illustrated in this article are (1) the major complications of large hiatal hernias: intrathoracic gastric volvulus and ulceration; (2) diaphragmatic abnormalities including inversion of the hemidiaphragm and intrathoracic displacement of abdominal contents because of diaphragmatic laceration or congenital herniation; (3) extrinsic displacement of the stomach bubble by splenomegaly (the occurrence of which in association with radiographic abnormalities in the chest--cardiomegaly, interstitial lung disease, mediastinal or hilar adenopathy--helps form a differential diagnosis); and (4) situs abnormalities for the analysis of which a simplified schema is presented.

Hernia, Diaphragmatic↗
PubMed1988

Upper lobe lung disease: physiologic correlates. Review.

Preferential localization of pathologic conditions in the upper lobes of the lung might seem unexpected, considering that both blood flow and ventilation predominate in the lower lobes. The erect lung is marked by striking regional non-uniformity in perfusion, ventilation, lymphatic flow, metabolism, and mechanics. These regional disparities form the foundation for a physiologic approach to the evaluation of diffuse lung disease. The pathologic-physiologic correlations in apical lung disease are examined, and a differential diagnosis is offered. Analysis of diffuse lung disease on the basis of radiologic-physiologic correlation is suggested as an aid in radiographic interpretation.

Humans↗
PubMed1987

Imaging in acute renal infection in children.

Infection is the most common disease of the urinary tract in children, and various imaging techniques have been used to verify its presence and location. On retrospective analysis, 50 consecutive children with documented upper urinary tract infection had abnormal findings on renal cortical scintigraphy with 99mTc-glucoheptonate. The infection involved the renal poles only in 38 and the poles plus other renal cortical areas in eight. Four had abnormalities that spared the poles. Renal sonograms were abnormal in 32 of 50 children. Excretory urograms were abnormal in six of 23 children in whom they were obtained. Vesicoureteral reflux was found in 34 of 40 children in whom voiding cystourethrography was performed. These data show the high sensitivity of renal cortical scintigraphy with 99mTc-glucoheptonate in documenting upper urinary tract infection. The location of the abnormalities detected suggests that renal infections spread via an ascending mode and implies that intrarenal reflux is a major contributing factor.

Acute Disease↗