PubMed Health⌕ Search

Biomedical subjects

B Colvin

Publications and source records attributed to B Colvin.

12 recordsLinked to original sources
PubMed2002

Venous thrombosis following the use of intermediate purity FVIII concentrate to treat patients with von Willebrand's disease.

We describe four patients with von Willebrand's disease (VWD) who experienced venous thrombosis after treatment with an intermediate purity factor VIII (FVIII) concentrate (Haemate P3) was used to cover invasive or surgical procedures. Most patients had additional risk factors for venous thromboembolism (VTE) and it is difficult to be certain of the contribution of the concentrate to the VTE. In view of the recognised association between high factor VIII activity (FVIII:C) levels and VTE there is a physiological basis for this complication and it is important to consider this when administering FVIII containing concentrates to VWD patients.

Adult↗
PubMed1999

Creation of a novel donor splice site in intron 1 of the factor VIII gene leads to activation of a 191 bp cryptic exon in two haemophilia A patients.

We have constructed a confidential U.K. database of haemophilia A mutations and pedigrees by characterizing the gene defect of one index patient in each U.K. family. Mutations were identified by screening all coding regions of the factor VIII (FVIII) mRNA, using solid-phase fluorescent chemical cleavage of mismatch and examining additional non-coding regions of the gene. Here we report two haemophilia A patients (UK 114 FVIII:C 2% and UK 243 FVIII:C < 1%) with an abnormal FVIII mRNA due to an A to G point mutation, 1.4 kb downstream from exon 1 in the FVIII gene. This mutation creates a new donor splice site in intron 1 and leads to insertion of a 191 bp novel exon in the mRNA. Haplotype analysis suggests that the mutation may have originated in a common ancestor of the two patients, who further illustrate how mRNA analysis allows higher efficiency of haemophilia A mutation detection, because their mutation would not have been identified by direct analysis of the factor VIII gene.

Base Sequence↗
PubMed1998

Microcystin toxicosis in cattle due to overgrowth of blue-green algae.

Toxicosis due to microcystin-containing blue-green algae has been sporadically reported in a variety of animal species. Most reports of intoxication involve algal blooms during periods of warm temperatures and abundant sunshine in the spring or early summer. A case of blue-green algae toxicosis with lesions attributable to toxins from Microcystis aeruginosa is described in 4 cattle from southern Georgia during November. The case was unusual in that characteristic hepatic necrosis was accompanied by severe mesenteric edema and peritoneal effusion. In addition, weather conditions and location were not expected to be conducive to algal blooms. Rapid diagnosis and identification of the probable source of intoxication allowed the owner to move the herd away from the affected pond. This action limited losses to only the 4 cattle.

Animals↗
PubMed1998

Bovine arsenic toxicosis from ingestion of ashed copper-chrome-arsenate treated timber.

Arsenic toxicosis is reported in a variety of animal species. It occurs most commonly in cattle and ranks second only to lead as a cause of heavy metal poisoning. We describe a case of arsenic toxicosis attributable to ingestion of ashes from burned posts treated with an arsenic-containing preservative. Burning of the posts concentrated the arsenic and rendered lethal a product normally used around livestock. Lack of normal salt supplementation to the herd was conducive to pica-like behavior and ingestion of toxic ashes. Rapid diagnosis led to removal of the arsenic source and limited losses to 4 cows.

Animals↗
PubMed1998

Postmortem diagnosis of accidental cocaine intoxication in a dog.

Despite an abundance of data on the experimental effects of cocaine in dogs, no detailed reports documenting accidental cocaine exposure in domestic pets have been reported in the veterinary literature. A case of cocaine intoxication is described in a 19-mo-old male catahoula hound in which the diagnosis was confirmed using histopathology, thin-layer chromatography and mass spectrometry. The case was presented as a possible intoxication of unknown etiology. Routine toxicologic screens and characteristic histologic lesions provided evidence for the diagnosis without prior suspicion of cocaine involvement.

Accidents↗
PubMed1992

Sequence analysis of an HIV-1 isolate which displays unusually high-level AZT resistance in vitro.

Multiple mutations in the reverse transcriptase (RT) gene were observed in a drug-resistant isolate of human immunodeficiency virus type 1 (HIV1) from an individual having prolonged (greater than 2 years) zidovudine (AZT) therapy. The virus replicated in PBMC's in the presence of very high concentrations of AZT (125 microM). Drug-sensitive strains were curtailed by 0.01 microM AZT. Eleven defined mutations were observed as compared with published sequences of RT for eight strains of HIV1. Eight of these mutations were found in the domain involved in nucleotide recognition and enzyme function. Only one of the mutations, giving a Thr--Tyr change at amino acid 215, matched those previously ascribed (67, 70, 215, and 219) to the generation of high-level resistance to AZT. Therefore additional amino acid changes may have significance in the emergence of super-resistant viruses.

Amino Acid Sequence↗
PubMed1992

Hydroxyethyl starch induced acquired von Willebrand's disease.

Hydroxyethyl starch (HES) (Hespan, DuPont) is a widely used synthetic volume expander which in standard doses of up to 1.5l in 24 h has no significant effect on coagulation (Munsch et al. 1988). However, the data sheet states that in large volumes HES may alter the coagulation mechanism. We now report a case of HES induced acquired von Willebrand's disease (vWD) in which severe bleeding occurred.

Adult↗
PubMed1992

The toxicologic investigation of a feed grain contaminated with seeds of the plant species Cassia.

Feed grain suspected of causing death in a group of pigs was evaluated for toxic potential in chickens. The contaminated grain sorghum mixture was examined visually and contained 3.7% Cassia occidentalis and 1.6% Cassia obtusifolia seeds by weight. Thirty-two chicks were fed a sample of this suspect grain sorghum mixture. Chickens receiving the contaminated grain lost weight rapidly, exhibited clinical signs typical of intoxication with Cassia spp., and by day 16 were severely debilitated. Necropsy and histologic and electron microscopic examinations demonstrated a skeletal and cardiac degenerative myopathy consistent with intoxication by Cassia occidentalis. These toxicologic investigations verified the toxic potential of the contaminated sorghum mixture for chickens, and these comparative observations support prior diagnostic efforts implicating Cassia spp. as a cause of illness in swine.

Animal Feed↗