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J Hill

Publications and source records attributed to J Hill.

At least 271 records · Page 15Linked to original sources
PubMed1991

Retinoic acid modifies development of the midbrain-hindbrain border and affects cranial ganglion formation in zebrafish embryos.

Considerable evidence now suggests that retinoic acid (RA) is an important modulator of patterning events in early neuronal development in vertebrates. In this paper, we describe the effects of exogenously applied RA on early neural development in the zebrafish embryo. Neural anatomy is assessed by immunocytochemical and histochemical analysis of the developing embryo in whole mounts at 24 h post-fertilization. RA was applied for one hour at concentrations ranging from 10(-9) to 10(-6) M to embryos at 50% epiboly, the midgastrula stage, and at 10(-7) M to embryos at early and late gastrula stages. The neuroanatomical analysis shows that 10(-7) M RA causes a defined lesion to the developing central nervous system which corresponds to a loss of a region of the brain in the caudal midbrain-rostral hindbrain area, the precursor of the cerebellum and associated neural structures. The region that fails to develop corresponds to the cranial expression domain of the engrailed protein as assessed by the monoclonal antibody 4D9 (Patel et al. 1989: Expression of engrailed proteins in arthropods, annelids and chordates. Cell 58, 955-968). Structures caudal to rhombomere 4 are unaffected by 10(-7) M RA, as are the cranial midbrain and forebrain: 10(-7) M RA also affects the development of cranial ganglia, principally the Vth, anterior lateral line and VIIIth ganglia, suggesting that RA affects normal development of the cranial neural crest. Effects of RA at stages immediately prior to and after gastrulation show some similar and some distinct features. Results are discussed in terms of the possible role of RA as an endogenous moderator of normal head development.

Animals↗
PubMed1991

Validity of the computerized DIS for diagnosing psychiatric inpatients.

The validity of a self-administered, computerized version of the National Institute of Mental Health Diagnostic Interview Schedule (DIS) was evaluated with a group of 41 psychiatric inpatients. Each patient was administered the computerized DIS (C-DIS) and a semi-structured clinical interview using the symptom checklist developed by Helzer et al. The concordance between the C-DIS and symptom checklist was comparable to that found in earlier studies of the original DIS. The overall distribution of kappas was also similar to those of previous studies. Overall, the results suggest that computerized administration may be a feasible alternative to face-to-face administration of the DIS.

Adolescent↗
PubMed1991

Suction curettage with a tissue trap compared with sharp curettage for tissue sampling.

Recent reports have shown that various endometrial sampling techniques are comparable to each other. This study showed that suction curettage utilizing tissue traps is superior to sharp curettage in terms of adequacy of sampling. The results show that adequate tissue was obtained in all 114 cases, regardless of which type of curettage was utilized first. However, when sharp curettage was the second procedure, only 43 of 57 procedures yielded adequate tissue, whereas when suction curettage was the second procedure, 56 of 57 procedures yielded adequate tissue. Suction curettage utilizing tissue traps was more thorough than sharp curettage.

Curettage↗
PubMed1990

Recent studies of the cytochrome o terminal oxidase complex of Escherichia coli.

The cytochrome o complex is the predominant terminal oxidase in the aerobic respiratory chain of Escherichia coli when the bacteria are grown under conditions of high aeration. The oxidase is a ubiquinol oxidase and reduces molecular oxygen to water. Electron transport through the enzyme is coupled to the generation of a protonmotive force. The purified cytochrome o complex contains four or five subunits, two protoheme IX (heme b) prosthetic groups, plus at least one Cu. The subunits are all encoded by the cyo operon. Sequence comparisons show that the cytochrome o complex is closely related to the aa3-type cytochrome c oxidase family. Gene fusions have been used to define the topology of each of the gene products. Subunits I, II, III and IV are proposed to have 15, 2, 5 and 3 transmembrane spans, respectively. The fifth gene product (cyoE) encodes a protein with 7 membrane spanning segments, and this may also be a subunit of this enzyme. Fourier transform infrared spectroscopy has been used to monitor CO bound in the active site where oxygen is reduced. These data provide definitive proof that the cytochrome o complex has a heme-copper binuclear center, similar to that present in the aa3-type cytochrome c oxidases. Site-directed mutagenesis is being utilized to define which amino acids are ligands to the heme iron and copper prosthetic groups.

Alkaline Phosphatase↗
PubMed1990

Specific regulation by endogenous polyamines of translational initiation of S-adenosylmethionine decarboxylase mRNA in Swiss 3T3 fibroblasts.

S-Adenosylmethionine decarboxylase (AdoMetDC) activity was elevated 18.8-fold in Swiss 3T3 fibroblasts which were depleted of cellular polyamines by using the inhibitor difluoromethylornithine (DFMO). Although the cellular level of AdoMetDC mRNA and the half-life of active AdoMetDC protein were also increased (4.3- and 1.5-fold respectively), together they could not account for the magnitude of the increase in AdoMetDC activity. These data suggested that the translation of AdoMetDC mRNA must be increased in the polyamine-depleted cells to account fully for the elevation in activity. The cellular distribution of AdoMetDC mRNA was examined in the polyamine-depleted cells, and it was found almost exclusively associated with large polysomes. In contrast, AdoMetDC mRNA in untreated controls was very heterogeneous, with the proportion associated with monosomes equal to that associated with large polysomes. The shift of the AdoMetDC message into large polysomes occurred within 18 h after addition of DFMO to the cultures and could be reversed by adding exogenous putrescine. The effect of polyamine depletion on AdoMetDC translation was specific, since there was no change in the distribution in polysomes of either actin mRNA or the translationally controlled mRNA encoding ribosomal protein S16 in the DFMO-inhibited cells. Thus the translational efficiency of AdoMetDC mRNA in vivo is regulated either directly or indirectly by the concentration of intracellular polyamines through a mechanism involving translational initiation, which results in a change in the number of ribosomes associated with this mRNA.

Adenosylmethionine Decarboxylase↗
PubMed1990

Home away from home.

Explore the source record for details and available documents.

Community Mental Health Services↗
PubMed1990

Adult outcomes of childhood and adolescent depression. I. Psychiatric status.

The present study was based on the clinical data summaries ("item sheets") of children who attended the Maudsley Hospital, London, England, during the late 1960s and early 1970s. These summaries were used to identify a group of 80 child and adolescent psychiatric patients with an operationally defined depressive syndrome. The depressed children were individually matched with 80 nondepressed psychiatric controls on demographic variables and nondepressive childhood symptoms by a computer algorithm. At follow-up, on average 18 years after the initial contact, information was obtained on the adult psychiatric status of 82% of the total sample. Adult assessments were made "blind" to case/control status. The depressed group was at an increased risk for affective disorder in adult life and had elevated risks of psychiatric hospitalization and psychiatric treatment. They were no more likely than the control group to have nondepressive adult psychiatric disorders. These findings suggested that there is substantial specificity in the continuity of affective disturbances between childhood and adult life.

Adolescent↗
PubMed1990

A multiple dose pharmacokinetic and tolerance study of once daily 200 mg sustained-release flurbiprofen capsules in young and very elderly patients.

The pharmacokinetic profile of 200 mg sustained-release flurbiprofen capsules was compared in nine elderly (mean age 84.2 years) and 10 young (mean age 38.1 years) patients with arthritis. After a single capsule, a 48 h plasma concentration profile was performed. The patients then took 1 capsule daily for a further 13 days with plasma levels of the drug being measured pre-dose on alternate days. Following ingestion of the last capsule, a further 48 hour plasma concentration profile was performed. These results were compared with each other and with computer predicted data obtained from dosing with 200 mg conventional flurbiprofen (as 100 mg b.d.). In both young and elderly patients, the two 48 h plasma concentration profiles confirmed the sustained-release characteristics of the capsule. There was no evidence of dose-dumping, although, in one elderly patient with a partial gastrectomy, higher plasma concentrations were observed. Inter- and intra-patient variability was acceptable. A steady-state was achieved within the predicted four days in both groups and there was no evidence of accumulation with the daily dosing interval. A mean steady-state level of approximately 6 micrograms/ml was achieved for both populations. Computer predicted data for 200 mg conventional flurbiprofen (as 100 mg b.d.) showed a pre-dose/peak range of 1-12 micrograms/ml. The pre-dose/peak ranges for the young and old patients were 4-10 micrograms/ml and 4-8 micrograms/ml respectively. One young patient developed a hypersensitivity reaction of moderate severity; one young and four elderly patients developed a low haemoglobin concentration during the study. No other changes in haematological or biochemical parameters were seen.

Adult↗
PubMed1990

Bolus doses of esmolol for the prevention of perioperative hypertension and tachycardia.

The effectiveness of esmolol, an ultra short-acting cardioselective beta blocker, in the prevention and treatment of post-intubation haemodynamic perturbations, was investigated. Forty-eight ASA physical status I and II patients undergoing hysterectomy were randomly assigned to receive a single intravenous bolus of placebo, esmolol 100 mg, or esmolol 200 mg in a double-blind fashion. This was administered over 15 sec, and immediately followed by thiopentone 3-5 mg.kg-1, succinylcholine 1.5 mg.kg-1, and tracheal intubation 90 sec later. The heart rate following induction of anaesthesia was lower in the esmolol 200 mg group (P less than 0.01); following intubation, the increase in heart rate in the placebo group was greater than in the esmolol groups (P less than 0.05). The systolic blood pressure post-induction was lower in the esmolol 200 mg group (P less than 0.05); following intubation, however, no significant differences were seen among groups in systolic, diastolic, or mean blood pressures. Following tracheal intubation, the incidence of ventricular arrhythmias was lower in the esmolol groups (P less than 0.05). In summary, esmolol in 100 mg and 200 mg doses was effective in mitigating the haemodynamic response following tracheal intubation.

Adrenergic beta-Antagonists↗
PubMed1990

The sensitivity and specificity of a modified ELISA for the diagnosis of Johne's disease from a field trial in cattle.

An enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies against Mycobacterium paratuberculosis in cattle was evaluated in three herds known to have Johne's disease. Prior to testing, the plasma was absorbed with dried Mycobacterium phlei in order to remove cross-reacting antibody specificities. The sensitivity and specificity of the ELISA were calculated after repeatedly testing 327 cattle in the infected herds. Of these, 53 animals had one or more positive faecal cultures or had post-mortem histopathological evidence of infection. The other 274 had three or more negative faecal culture results, and were regarded as non-infected for the purpose of evaluation of the ELISA. Using these criteria for the presence or absence of infection, the M. phlei-absorbed ELISA under field conditions had a 57% sensitivity and a 98.9% specificity. The sensitivity of the absorbed ELISA depended on the stage of disease of the animal under test. In general, it appeared that animals in the more advanced stages of disease were absorbed ELISA positive, whereas those in the early stages of infection were not detected. These results indicate that the M. phlei-absorbed ELISA has an important role as a test for the diagnosis and control of Johne's disease in cattle.

Animals↗
PubMed1990

Late development of a squamous carcinoma in a reconstructed pharynx.

We report a case in which a squamous cell carcinoma was found to have arisen from a delto-pectoral skin flap used in pharyngeal reconstruction. The flap had been forming a neo-pharynx for 24 years. No other signs of recurrent disease had developed in this period. This raises the possibility of tumour induction in heterotopic skin used for oropharyngeal reconstruction.

Carcinoma, Squamous Cell↗
PubMed1990

Sequence and structure in the concept development of children with emotional and behavioral difficulties.

We investigated the order of acquisition of concepts and cognitive processes in children with emotional and behavioral difficulties and the extent to which these children show similarity to ordinary children in sequence and structure of development. Similarity in developmental sequence was strongly supported by scalogram analyses and has clear implications for organizing teaching, but similarity in structure was less clear. Cognitive processes however, and the nature of the children's reasoning were clarified by the method of exploration used. This was particularly fruitful for providing insight into the difficulties children may have. The findings thus contribute to understanding with a view toward furthering concept development in children with emotional and behavioral difficulties.

Adolescent↗
PubMed1990

The arthritis impact measurement scales: an anglicized version to assess the outcome of British patients with rheumatoid arthritis.

The Arthritis Impact Measurement Scales (AIMS) is an American questionnaire designed to measure the health status of patients with arthritis. Its suitability for use with British patients with rheumatoid arthritis (RA) has been tested. A study on 30 patients high-lighted the need to anglicize the terminology and spelling. A further 30 patients found the modified questionnaire easier to complete than the original. The concurrent validity of this modified AIMS was then tested on 59 patients by comparison with two widely accepted standards. Physical function and pain scales were tested against the Stanford Health Assessment Questionnaire (HAQ). Because the HAQ has no psychological component, psychological status was compared with the Hospital Anxiety and Depression Scale (HAD). Results showed a good correlation between the scales and it is concluded that the modified version of the AIMS may be used with confidence in British patients with RA.

Adult↗
PubMed1990

Failure of selenium-ace to improve osteoarthritis.

Selenium-ACE, a formulation containing the trace element selenium with three vitamins, is widely promoted for the treatment of arthritis. A controlled double-blind trial of Selenium-ACE in osteoarthritis failed to demonstrate any significant efficacy for the compound over placebo at 3 or 6 months though there was a non-significant trend to improvement in some clinical parameters in both groups. Side-effects were more frequently seen in the placebo group.

Adult↗
PubMed1990

A multicentre double-blind comparison of auranofin, intramuscular gold thiomalate and placebo in patients with psoriatic arthritis.

The efficacy and safety of the oral gold compound auranofin and intramuscular gold thiomalate have been compared in a placebo-controlled, double-blind, four-centre trial in 82 patients with psoriatic arthritis requiring remittive drug therapy. There were statistically significant falls in Ritchie articular index, visual analogue pain score and ESR at 12 and 24 weeks following i.m. gold but no significant changes in the auranofin group. Intramuscular gold was safe and more effective than auranofin as a second-line, suppressive antirheumatic agent for patients with psoriatic arthritis when followed for 6 months.

Adult↗
PubMed1990

Methylsulphasalazine in rheumatoid arthritis.

Methylsulphasalazine, which differs from sulphasalazine by the addition of one methyl group, may provide the benefits of the parent drug with fewer side-effects in rheumatoid arthritis (RA). We describe the outcome of its use in RA. Of 21 patients entered into the study, 10 successfully completed 6 months of therapy; five developed adverse effects, four withdrew for reasons unrelated to drug treatment and two stopped because of inefficacy. No serious adverse effects were reported. A statistically significant improvement in most clinical assessments was observed from weeks 8-12 onwards. Significant improvement in plasma viscosity was observed and there was a trend towards improvement in serum CRP, histidine and IgM concentrations. There was a good correlation between mean serial changes in clinical and biochemical assessments indicating that the drug may exhibit the properties of a second-line agent. Median steady-state serum concentrations of methylsulphasalazine and methylsulphapyridine were 26.6 micrograms/ml and 2.85 micrograms/ml respectively.

Adult↗