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Biomedical subjects

J Daniels

Publications and source records attributed to J Daniels.

At least 37 records · Page 2Linked to original sources
PubMed1996

Liver hemorrhage during laparotomy in patients with necrotizing enterocolitis.

UNLABELLED: Major liver hemorrhage (LH) without obvious iatrogenic injury was recently observed in several patients during operation for necrotizing enterocolitis (NEC). The purpose of this study was to determine the incidence and risk factors associated with the development of LH in patients with NEC. METHODS: The hospital charts of patients with NEC who underwent surgical exploration during a 5-year period (1989-1994) were reviewed. The patients in whom LH developed without obvious significant iatrogenic liver injury were compared with those who did not have LH. RESULTS: Eight of the 68 patients reviewed had LH. The survival rate for those with LH was 13%, compared with 88% for those without LH (P < .001). The patients with LH had a younger gestational age (28 +/- 3 weeks v 32 +/- 5 weeks) and a lower birth weight (1,262 +/- 489 g v 1,649 +/- 666 g); however, the differences were not significant. The patients with LH had significantly lower preoperative mean arterial blood pressure (35 +/- 1 mm Hg v 46 +/- 3 mm Hg; P < .001) and required greater fluid intake (272 +/- 28 mL/kg/d v 186 +/- 9 mL/kg/d; P < .01) for the 24 hours preceding surgery. CONCLUSION: LH is as an important and lethal complication associated with laparotomy in very small infants with NEC. The presence of hypotension and the administration of large amounts of volume in the preoperative period appear to be risk factors. Earlier surgical intervention and restoration of blood pressure using inotropic agents, once a particular level of fluid administration has been achieved, my be preventive.

Birth Weight↗
PubMed1996

Association study of bipolar disorder at the phospholipase A2 gene (PLA2A) in the Darier's disease (DAR) region of chromosome 12q23-q24.1.

We have previously described a pedigree in which affective disorder and Darier's disease cosegregate and, in an independent sample of 45 bipolar pedigrees, reported evidence in support of linkage between a putative susceptibility locus for bipolar disorder and markers in the Darier's disease region of chromosome 12q23-q24.1. The maximum evidence for linkage was given by a polymorphism at the gene encoding secretory phospholipase A2 (PLA2A), a candidate gene for affective disorder. Dawson et al. (Psychiatric Genetics, 5, 177-180) recently reported allelic association with the same polymorphism at PLA2A in a sample of 54 bipolar probands and 56 controls. We have been unable to replicate the association in 127 Caucasian British DSMIII-R bipolar probands and 223 Caucasian British controls. However, on the basis of several lines of evidence discussed in the paper, we believe that this genomic region in general, and the PLA2A gene in particular, are worthy of further study as candidates in the search for susceptibility genes for the functional psychoses.

Alleles↗
PubMed1996

Facilitating the recovery of open heart surgery patients through quality improvement efforts and CareMAP implementation.

OBJECTIVE: To illustrate, using a literature review and CareMAPs, how care coordination and implementation of standard protocols can impact clinical outcomes for open heart surgery patients. METHODS: A CareMAP for open heart surgery patients was developed by a multidisciplinary team. To evaluate the effectiveness of CareMAP implementation and specific quality improvement efforts, a pilot study was done that focused on increasing activity levels, decreasing ventilator time, and decreasing the frequency of arterial blood gas sampling for a sample of 55 open heart surgery patients. A rapid recovery program was developed based on the results of this pilot study. A multidisciplinary continuous quality improvement team was developed to focus on three primary areas: ventilator weaning time, activity regimens, and early transfer to the open heart surgery step-down unit. Forty-nine open heart surgery patients were included in the initial program evaluation. RESULTS: The frequency of arterial blood gas sampling decreased from an average of 5.8 per patient to an average of 3.9 per patient. Postoperative length of stay also decreased by 1.3 days for diagnosis related group 106 patients, and 3.7 days for diagnosis related group 107 patients. Results of the pilot study demonstrated additional opportunities for improving the care of open heart surgery patients. Using the rapid recovery program, the average ventilator time decreased by 4.4 hours per patient. The average postoperative length of stay decreased to 4.7 days. CONCLUSIONS: Through the quality improvement process and through the use of CareMAPs and specific protocols, the recovery of open heart surgery patients was facilitated.

Analysis of Variance↗
PubMed1996

Increasing the efficiency of genomic searches for linkage in complex disorders by DNA pooling of affected sib-pairs.

Detection of linkage using a systematic genome scan in nuclear families including an affected sibling pair is an important initial step on the path to cloning susceptibility genes for complex genetic disorders such as bipolar disorder and schizophrenia. We describe a novel method in which the pooled genotype of each affected sib-pair is determined and used in the screening stage of a two-stage genome scan. This method, which involves a single PCR reaction per sib-pair in the screening stage can reduce the required number of genotypings to less than 20% of those required in a conventional single stage procedure whilst maintaining a similar power and probability of type I error.

Bipolar Disorder↗
PubMed1995

No evidence for allelic association between bipolar disorder and monoamine oxidase A gene polymorphisms.

We have tested the hypothesis that DNA markers in the MAOA gene show allelic association with bipolar affective disorder. Eighty-four unrelated Caucasian patients with DSM III-R bipolar disorder and 84 Caucasian controls were typed for three markers in MAOA: a dinucleotide repeat in intron 2, a VNTR in intron 1, and an Fnu4HI RFLP in exon 8. No evidence for allelic association was observed between any of the markers and bipolar disorder.

Adult↗
PubMed1995

Linkage studies of bipolar disorder in the region of the Darier's disease gene on chromosome 12q23-24.1.

We have recently described a family in which there is cosegregation of major affective disorder with Darier's disease and have mapped this autosomal dominant skin disorder to 12q23-q24.1. This has provided an interesting candidate region for genetic studies of bipolar disorder. We have studied the segregation of seven markers spanning the Darier's disease locus in 45 bipolar disorder pedigrees and found modest evidence in support of linkage under heterogeneity for 5 of these markers. Nonparametric analyses were suggestive of linkage with a marker at the gene encoding a secretory form of phospholipase A2. Our sample has relatively low power to detect linkage under heterogeneity and independent researchers should examine markers from this region in further samples of bipolar pedigrees.

Alleles↗
PubMed1995

No association between schizophrenia and polymorphisms within the genes for debrisoquine 4-hydroxylase (CYP2D6) and the dopamine transporter (DAT).

It has been suggested that the cytochrome P450 mono-oxygenase, debrisoquine 4-hydroxylase, is involved in the catabolism and processing of neurotransmitters subsequent to their reuptake into target cells. It is also thought to be related to the dopamine transporter that acts to take released dopamine back up into presynaptic terminals. The present study used the association approach to test the hypothesis that mutations in the genes for debrisoquine 4-hydroxylase (CYP2D6) and the dopamine transporter (DAT) confer susceptibility to schizophrenia. There were no differences in allele or genotype frequencies between patients and controls in the mutations causing the poor metaboliser phenotype in CYP2D6. In addition there was no association found between schizophrenia and a 48bp repeat within the 3' untranslated region of DAT.

Adolescent↗
PubMed1995

Partial characterization and assignment of the gene for protoporphyrinogen oxidase and variegate porphyria to human chromosome 1q23.

Protoporphyrinogen oxidase (PPO) catalyses the conversion of protoporphyrinogen IX to protoporphyrin IX. Variegate porophyria (VP), a low-penetrant, autosomal dominate disorder characterized clinically by skin lesions and neurovisceral attacks, is caused by partial deficiency of this enzyme. Linkage between VP and the alpha-1-antitrypsin gene on chromosome 14 has been reported in VP families from South Africa, where the condition occurs at high frequency due to a founder effect. We have cloned a 4.5 kb genomic DNA fragment containing the entire coding sequence for human PPO. This clone has been used to localize the human PPO gene to chromosome 1q23 by fluorescence in situ hybridization analysis. The VP gene was mapped by linkage analysis, using microsatellite markers spanning the region 1q21-q25.1, in seven British VP families. Multipoint analysis between VP, SPTA1, APOA2 and D1S194 gave the maximum LOD score of 6.62 at APOA2, which has been physically mapped to 1q21-q23. Evidence for significant linkage between VP and markers in the alpha-1-antitrypsin region of chromosome 14 was not obtained. Our results assign the genes for PPO and VP to the same region chromosome 1, indicate that the PPO and VP loci are likely to be the same, and provide evidence against locus heterogeneity in VP.

Adolescent↗
PubMed1994

Repeat length variation in the dopamine D4 receptor gene shows no evidence of association with schizophrenia.

The D4 receptor has been shown to exist in several allelic forms (Van Tol et al., Nature 358:149-152, 1992) reflecting variation in the number of 48 base-pair sequence repeats in the putative cytoplasmic loop. We report a comparison of repeat length variation between schizophrenic patients and controls. Our sample of 106 unrelated schizophrenic cases and 119 controls showed no significant differences in allele or genotype distribution between patients and controls. In particular, we were unable to support the previous observation of an excess of 4-repeat homozygotes in patients.

Alleles↗
PubMed1994

Variation at the fragile X locus does not influence susceptibility to bipolar disorder.

Over the last 20 years several pedigrees have been reported which are suggestive of linkage between susceptibility to bipolar disorder and markers on chromosome Xq28. Other workers have failed to replicate these reports and the methodology of the positive reports has been criticised. Recently there have been several reports of an association between fragile X (FRA(X)) and affective disorder within families and in unrelated individuals compared with controls. Such reports could be consistent with the Xq28 marker reports because FRA(X) maps to Xq27.3. We report a study at the FRA(X) CGG repeat locus in 79 unrelated Caucasian bipolar probands without fragile X syndrome and 77 unrelated controls. We found no evidence that variation at this locus confers susceptibility to bipolar disorder.

Adult↗
PubMed1994

Association and haplotype analysis at the tyrosine hydroxylase locus in a combined German-British sample of manic depressive patients and controls.

Tyrosine hydroxylase (TH) is the key enzyme in the synthesis of catecholamines and may therefore be of aetiological relevance in the development of psychiatric illness. Hipolar affective disorder association studies, with restriction fragment length polymorphisms located in flanking regions of the TH gene, have shown conflicting results. Alleles of a tetranucleotide repeat polymorphism (TH4) located in intron 1 of the gene were tested for association with bipolar affective disorder in a combined German and British sample of 183 bipolar patients and 209 healthy control probands. No differences in TH4 allele frequencies were found in the two groups. A subset of patients and controls was typed with the flanking markers Ty7/BglII and pJ4.7/TaqI and frequencies of two-locus haplotypes were estimated. Linkage disequilibrium was found between TH4-Ty7 and TH4-pJ4.7. Haplotype frequencies did not differ between patients and controls.

Alleles↗
PubMed1994

An evaluation of a pre-scaling gel (SofScale) on the ease of supragingival calculus removal.

SofScale is a pre-scaling gel, containing disodium EDTA and sodium lauryl sulphate, which is claimed to soften calculus and therefore facilitate its removal. 31 subjects were treated in a double blind randomised placebo controlled split mouth study to evaluate this product. Test or placebo gels were applied to the lingual surfaces of the mandibular teeth for 4 min and the time taken to complete the removal of supragingival calculus recorded. The operator recorded on which side the calculus was considered easier to remove and the patient indicated how comfortable the scaling had been. The mean calculus index was 1.99 for the SofScale group and 1.97 for the placebo. The mean time taken to complete scaling was 5.31 min for both groups. Using the Student t-test, there were no statistically significant differences (p > 0.7) between either the calculus index or time taken to complete the scaling between the groups. The operator did not consider SofScale to facilitate calculus removal and patients did not find calculus removal more comfortable when SofScale had been used. There was no increased sensitivity in the SofScale group following scaling. The results of this study do not support the use of SofScale as an adjunct to scaling.

Adult↗
PubMed1993

The gene for Darier's disease maps to chromosome 12q23-q24.1.

Darier's disease is a rare autosomal dominant skin disorder in which there is abnormal adhesion between keratinocytes. It appears to be associated with an increased prevalence of neuropsychiatric disorders including mental retardation and epilepsy. In addition we have previously reported a family in which major affective disorder cosegregates with Darier's disease. In the present study we have localized the gene for Darier's disease to chromosome 12q23-q24.1 by linkage analysis in five British pedigrees. We obtained a maximum two point lod score of 4.29 with marker D12S84 at zero recombination fraction. All five families showed evidence of linkage between the disease gene and markers in this region. Subsequent identification of the Darier's disease gene will provide insights into normal mechanisms of cell adhesion and may be of importance in the genetic investigation of neuropsychiatric disorders as well as elucidating the pathogenesis of Darier's disease itself.

Chromosome Mapping↗
PubMed1992

Isolation and amplification of human IgE Fd encoding mRNA from human peripheral blood lymphocytes.

In order to establish the feasibility of applying recombinatorial library technologies to investigate human in vivo IgE responses, and as a pre-requisite of recombinatorial library construction, we have attempted to determine workable peripheral blood sample volumes required for isolation of mRNA for polymerase chain reaction (PCR) amplification of human IgE Fd encoding sequences. Cells secreting chimeric human IgE monoclonal antibody specific for the hapten NIP were used to establish the conditions for specific amplification of C epsilon 1 domain and Fd encoding sequences, as determined by Southern hybridisation. Amplification of C epsilon 1 domain sequences could be achieved using as few as ten cultured cells as the source of RNA. Specific IgE+ B cell enrichment using immuno-magnetic particles prior to RNA extraction was, however, required to obtain amplification of IgE C epsilon 1 and Fd fragments from lymphocytes prepared from 40 ml human peripheral blood. IgG1+ B cell enrichment from similar samples was not required for detectable amplification of human C gamma 1 cDNA sequences. However, this procedure improved amplification efficiency. Optimisation of methods to separate specific B cell populations, or specific RNA/cDNA sequences, will facilitate in vitro generation of human IgE Fab fragments from peripheral blood.

B-Lymphocytes↗
PubMed1992

Diagnostic correlation of fiberoptic bronchoscopic biopsy and bronchoscopic cytology performed simultaneously.

The reliability of bronchoscopic cytology relative to biopsy is controversial. Some still consider biopsy the definitive procedure. Comparative studies are few and limited in scope. Therefore, we compared simultaneously obtained biopsies and cytologies for 224 cases. One hundred and sixty-six cases (74.6%) correlated completely. Forty-four cases (19.6%) did not correlate and cytology was diagnostic in 24 of these. Biopsy was diagnostic in sarcoidosis and vasculitis, whereas cytology only excluded the presence of neoplasm or infection. In 14 cases (5.8%), biopsy and cytology showed pathologic changes, but one or the other was more definitive. Rarely, the 2 techniques provided complementary information. A specific diagnosis was obtained more often from the combination of cytology and biopsy than from either alone. However, when biopsy is contraindicated it is reassuring that cytology usually yields the same information as biopsy, and can detect neoplastic and infectious diseases when the biopsy is non-diagnostic.

Biopsy↗