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T Smith

Publications and source records attributed to T Smith.

At least 73 records · Page 4Linked to original sources
PubMed2001

A role for HNF-3 in the regulation of the HNF-1 gene of the Atlantic salmon.

Hepatocyte nuclear factors -1 (HNF-1) and -3 (HNF-3) are hepatocyte-enriched transcription factors that are central to the establishment and maintenance of the liver phenotype in vertebrates. In the present study we demonstrate that, in the Atlantic salmon, asHNF-3 regulates the expression of the gene for asHNF-1. Multiple putative binding sites for asHNF-3 were identified within the 5' flanking region of the HNF-1 gene using a computer-based algorithm, and these were confirmed to be functional by electrophoretic mobility shift assays. In transient transfection assays it was shown that co-expression of asHNF-3 leads to a decrease in the promoter activity of the 5' flanking region of the asHNF-1 gene.

Animals↗
PubMed2001

Steroid enzyme gene expressions during natural and androgen-induced gonadal differentiation in the rainbow trout, Oncorhynchus mykiss.

In fish, according to Yamamoto's model, androgens would drive testis differentiation and estrogens ovarian differentiation. In order to study the implication of steroid enzymes in rainbow trout gonadal differentiation, we examined the expression of some steroid enzyme genes during natural differentiation (cholesterol side chain cleavage = P450scc, 17-hydroxylase/lyase = P450c17, 3beta-hydroxysteroid dehydrogenase = 3betaHSD) and androgen-induced differentiation (P450scc, P450c17, 3betaHSD, aromatase = P450aro, and 11beta-hydroxylase = P45011beta). Expressions of P450scc, 3betaHSD, and P450c17 were all detected in male and female gonads at 55 days post-fertilization (dpf), i.e., two weeks before histological differentiation. There were no differences in their expression level respective to the sex. The androgen treatment was carried out by administration of 11beta-hydroxyandrostenedione (11betaOHDelta4) in genetic all-female populations and the resulting sex ratios were found to be 100% male even at a low dosage of 1 mg/kg of food. Following 11betaOHDelta4 treatment, only the expression of P450c17 was found to be sustained when compared with the female untreated control. In contrast, P450scc was clearly up-regulated and 3betaHSD and P450aro down-regulated by the androgen treatment. P45011beta gene expression remained low in gonads of androgen-treated females, as it did in control untreated females. These results together demonstrate that steroidogenesis in rainbow trout is potentially active in pre-differentiating gonads of both sexes, and that one of the masculinizing actions of androgens in the species may be to down-regulate the female-specific gonadal P450aro gene expression. However, in vivo androgen treatment in genetic females does not induce the same pattern of steroid gene expression as in genetic males. These data suggest that exogenous androgens might induce a male differentiation process with P450aro inhibition being one of the steps required. However, this process would not involve endogenously produced 11-oxygenated androgens.

Androgens↗
PubMed2001

Novel mutations of MYO15A associated with profound deafness in consanguineous families and moderately severe hearing loss in a patient with Smith-Magenis syndrome.

Mutations in myosin XVA are responsible for the shaker 2 ( sh2) phenotype in mice and nonsyndromic autosomal recessive profound hearing loss DFNB3 on chromosome 17p11.2. We have ascertained seven families with profound congenital hearing loss from Pakistan and India with evidence of linkage to DFNB3 at 17p11.2. We report three novel homozygous mutations in MYO15A segregating in three of these families. In addition, one hemizygous missense mutation of MYO15A was found in one of eight Smith-Magenis syndrome (del(17)p11.2) patients from North America who had moderately severe sensorineural hearing loss.

Abnormalities, Multiple↗
PubMed2001

Paclitaxel in the multimodality treatment for inflammatory breast carcinoma.

BACKGROUND: Inflammatory breast carcinoma (IBC) is a rare but aggressive form of breast carcinoma. Anthracycline-based regimens represent the standard of treatment for IBC. Reports of significant clinical activity of paclitaxel in metastatic breast carcinoma led the authors to investigate the role of this drug in the management of IBC. METHODS: Forty-four patients with IBC were enrolled between February 1994 and January 1998. The treatment plan consisted of induction chemotherapy (IC), mastectomy, adjuvant chemotherapy, and radiotherapy. Forty-two patients received IC with four cycles of fluorouracil, doxorubicin, and cyclophosphamide. If the clinical response was less than partial, patients were "crossed over" to paclitaxel before mastectomy. All patients received adjuvant paclitaxel. Patients unresectable after paclitaxel were offered high-dose chemotherapy with autologous peripheral blood progenitor cell support. RESULTS: Thirty-four patients (81%) achieved an objective clinical remission; 3 patients (7%) achieved a clinical complete remission, 31 (74%) a partial remission. Six patients (14%) achieved pathologic complete remission. Sixteen patients were treated with paclitaxel, 7 of them (44%) were able to undergo mastectomy. Median time to progression (TTP) was 22 months. Median overall survival (OS) was 46 months. Concordance between clinical and pathologic response was documented in only 8 patients (24%). No differences in TTP and OS compared with a historical group of 178 IBC patients treated with anthracycline-based regimens. CONCLUSIONS: Paclitaxel improves tumor resectability in anthracycline-refractory IBC. The impact of paclitaxel on the prognosis of IBC needs to be better evaluated in future trials using more dose-intensive schedules of administration. New imaging modalities may contribute to improve assessment of response to IC.

Adenocarcinoma↗
PubMed2001

Seizures induce phase shifts of rat circadian rhythms.

RATIONALE: Epileptic seizures may alter neuroendocrinological cycles. Light pulses induce phase shifts in circadian rhythms. Using hippocampal-kindled rats to ensure maximal clinical expression, we determined if seizures likewise induce phase shifts. METHODS: We monitored the circadian rhythm of temperature (CRT) with intraperitoneal radiotelemetry in rats (n=21) isolated from time cues and light for 3-week trials. Seizures were triggered with hippocampal electrical stimulation at different circadian phases. Optimized, least-error phase shifts were calculated from preictal and postictal CRTs. Induced seizures were referenced to CRT (t(max)=00:00, 24-h circadian cycle). RESULTS: Phase shifts (individual responses=57) differed across the circadian cycle. Rather than forming a clear phase-response curve, phase shifts were especially variable between 00:00 and 06:00 h. CONCLUSIONS: This study demonstrates that electrically-induced seizures induce advances and delays in CRT in a phase-dependent fashion but in a pattern different from typical light-induced phase shifts. Disorders of circadian regulation may contribute to some of the altered endogenous cycles associated with epilepsy.

Animals↗
PubMed2001

A Phase I study of infusional vinblastine in combination with the P-glycoprotein antagonist PSC 833 (valspodar).

BACKGROUND: PSC 833 is a second-generation P-glycoprotein (Pgp) antagonist developed to reverse multidrug resistance (MDR). The authors conducted a Phase I study of orally administered PSC 833 in combination with vinblastine administered as a 5-day continuous infusion. METHODS: Seventy-nine patients with advanced malignant disease were enrolled in the trial and treated with escalating doses of PSC 833. Pharmacokinetic interactions between PSC 833 and vinblastine were anticipated. Accordingly, when dose limiting toxicities were observed, the dose of vinblastine was reduced as PSC 833 was escalated. Three schedules and two formulations of PSC 833 were used in the study. RESULTS: The maximum tolerated doses of PSC 833 were 12.5 mg/kg orally every 12 hours for 8 days for the liquid formulation in combination with 0.9 mg/m(2) per day vinblastine as a continuous intravenous infusion (CIV) for 5 days; and 4 mg/kg orally every 6 hours for 8 days for the microemulsion formulation in combination with 0.6 mg/m(2) per day vinblastine CIV for 5 days. The principal toxicities for PSC 833 were ataxia and paresthesias and for the combination, constipation, fever. and neutropenia. Increased oral bioavailability and increased peak and trough concentrations were observed with the microemulsion formulation. Significant interpatient variability in pharmacokinetic parameters was observed. Ten patients studied at the MTD for PSC 833 (4 mg/kg orally every 6 hours for 8 days) had inhibition of rhodamine efflux from CD56 positive peripheral lymphocytes as a surrogate for Pgp antagonism. Among 43 evaluable patients with clear cell carcinoma of the kidney, 3 patients had complete responses, and 1 patient had a partial response. CONCLUSIONS: PSC 833 in combination with vinblastine can be administered safely to patients provided the vinblastine dose is adjusted for pharmacokinetic interactions. The high interpatient variability is a significant confounding factor. Surrogate studies with CD56 positive cells suggest that Pgp inhibition in the clinical setting is achievable. Improved methods for predicting pharmacokinetic interactions should improve future studies.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

The impact of indoor residual spraying with malathion on malaria in refugee camps in eastern Sudan.

An exploratory trial of the efficacy of indoor spraying with malathion on morbidity and mortality in refugee camps in eastern Sudan was conducted during the rainy season of 1997. The interior walls of houses from a randomly selected group of five camps were sprayed with malathion in mid-September and morbidity and mortality rates in the camps for the months October to December compared with rates in five controls. Pyrethrum spray collection and human landing catches were performed in two collection rounds. An exophagic but endophilic population of Anopheles arabiensis was the most common mosquito collected. The mean human blood index of 242 mosquitoes from eight camps was 0.51. Only two of 1040 mosquitoes examined harboured sporozoites. Blood samples of 83 putative malaria patients were examined for parasites by PCR. Mortality rates in the 3 months following spraying were significantly lower in sprayed camps although differences in clinical malaria incidence between sprayed and non-sprayed camps were not significant.

Animals↗
PubMed2001

Teaching hospitals. Push me, pull you.

The Alder Hey Inquiry concluded that trust between Liverpool University and the hospital could have avoided the 'worst excesses'. In the past decade policies in health and higher education have weakened the long-established mutuality of hospitals and universities. Formal partnership arrangements are urgently needed.

Communication↗
PubMed2001

Prospective risk of morbidity in relation to multiplicity of infection with Plasmodium falciparum in São Tomé.

The prospective risk of acute morbidity was analysed in relation to multiplicity of Plasmodium falciparum infection in 491 individuals in a peri-urban community in São Tomé. In an initial cross-sectional survey, 40.5% of individuals were recorded by microscopy as infected with P. falciparum, and by PCR 60.5%, with the maximum prevalence in children aged 5-10 years. PCR-RFLP typing of the msp-2 gene of P. falciparum found a mean of 2.4 parasite genotypes per infected person, with little age dependence in this multiplicity and a total of 43 different msp-2 alleles identified. None of these were unique for São Tomé. Study participants were encouraged to report to a project worker whenever they suffered a febrile illness. During the 3 months following the parasitological survey the recorded incidence rates decreased with increasing baseline msp-2 multiplicity, both for P. falciparum-positive episodes and for fever without parasitaemia. While this is consistent with suggestions that multiple P. falciparum infections may protect against super-infecting parasites, confounding by patterns of health service usage is an alternative explanation. The incidence of clinical malaria episodes was only a little higher in children than in adults. This weak age-dependence in clinical immunity might be a consequence of a cohort effect resulting from resurgence of the disease after the breakdown of malaria control programs in the 1980s.

Adolescent↗
PubMed2001

Impact on malaria morbidity of a programme supplying insecticide treated nets in children aged under 2 years in Tanzania: community cross sectional study.

OBJECTIVE: To assess the impact of a social marketing programme for distributing nets treated with insecticide on malarial parasitaemia and anaemia in very young children in an area of high malaria transmission. DESIGN: Community cross sectional study. Annual, cross sectional data were collected at the beginning of the social marketing campaign (1997) and the subsequent two years. Net ownership and other risk and confounding factors were assessed with a questionnaire. Blood samples were taken from the children to assess prevalence of parasitaemia and haemoglobin levels. SETTING: 18 villages in the Kilombero and Ulanga districts of southwestern Tanzania. PARTICIPANTS: A random sample of children aged under 2 years. MAIN OUTCOME MEASURES: The presence of any parasitaemia in the peripheral blood sample and the presence of anaemia (classified as a haemoglobin level of <80 g/l). RESULTS: Ownership of nets increased rapidly (treated or not treated nets: from 58% to 83%; treated nets: from 10% to 61%). The mean haemoglobin level rose from 80 g/l to 89 g/l in the study children in the successive surveys. Overall, the prevalence of anaemia in the study population decreased from 49% to 26% in the two years studied. Treated nets had a protective efficacy of 62% (95% confidence interval 38% to 77%) on the prevalence of parasitaemia and of 63% (27% to 82%) on anaemia. CONCLUSIONS: These results show that nets treated with insecticide have a substantial impact on morbidity when distributed in a public health setting.

Bedding and Linens↗
PubMed2001

Phase I study of infusional paclitaxel in combination with the P-glycoprotein antagonist PSC 833.

PURPOSE: PSC 833 (valspodar) is a second-generation P-glycoprotein (Pgp) antagonist developed to reverse multidrug resistance. We conducted a phase I study of a 7-day oral administration of PSC 833 in combination with paclitaxel, administered as a 96-hour continuous infusion. PATIENTS AND METHODS: Fifty patients with advanced cancer were enrolled onto the trial. PSC 833 was administered orally for 7 days, beginning 72 hours before the start of the paclitaxel infusion. Paclitaxel dose reductions were planned because of the pharmacokinetic interactions known to occur with PSC 833. RESULTS: In combination with PSC 833, maximum-tolerated doses were defined as paclitaxel 13.1 mg/m(2)/d continuous intravenous infusion (CIVI) for 4 days without filgrastim, and paclitaxel 17.5 mg/m(2)/d CIVI for 4 days with filgrastim support. Dose-limiting toxicity for the combination was neutropenia. Statistical analysis of cohorts revealed similar mean steady-state concentrations (C(pss)) and areas under the concentration-versus-time curve (AUCs) when patients received paclitaxel doses of 13.1 or 17.5 mg/m(2)/d for 4 days with PSC 833, as when they received a paclitaxel dose of 35 mg/m(2)/d for 4 days without PSC 833. However, the effect of PSC 833 on paclitaxel pharmacokinetics varied greatly among individual patients, although a surrogate assay using CD56+ cells suggested inhibition of Pgp was complete or nearly complete at low concentrations of PSC 833. Responses occurred in three of four patients with non-small-cell lung cancer, and clinical benefit occurred in five of 10 patients with ovarian carcinoma. CONCLUSION: PSC 833 in combination with paclitaxel can be administered safely to patients provided the paclitaxel dose is reduced to compensate for the pharmacokinetic interaction. Surrogate studies with CD56+ cells indicate that the maximum-tolerated dose for PSC 833 gives serum levels much higher than those required to block Pgp. The variability in paclitaxel pharmacokinetics, despite complete inhibition of Pgp in the surrogate assay, suggests that other mechanisms, most likely related to P450, contribute to the pharmacokinetic interaction. Future development of combinations such as this should include strategies to predict pharmacokinetics of the chemotherapeutic agent. This in turn will facilitate dosing to achieve comparable CPss and AUCs.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

Pharmacokinetics and tolerability of 40-0-[2-hydroxyethyl]rapamycin in de novo liver transplant recipients.

BACKGROUND: 40-0-[2-Hydroxyethyl]rapamycin (RAD), a novel macrolide with potent immunosuppressive and antiproliferative activities, prevents rejection in animal allotransplantation models. This phase I trial assessed the effects of bile diversion, administration route, and time after transplant on RAD pharmacokinetics after single-dose administration in de novo liver allograft recipients. The influence of RAD on cyclosporine (CsA) pharmacokinetics and the safety of RAD were also evaluated. METHODS: Twenty-six de novo liver allograft recipients were assigned to one of four treatment groups based on the presence or absence of a T tube, administration route (nasogastric or nasoduodenal), and timing of RAD administration. Patients received a single 7.5-mg RAD dose on one to three occasions in addition to CsA (Neoral) and corticosteroids. Steady-state cyclosporine profiles with and without RAD coadministration were evaluated. Results. Recipients with bile diversion demonstrated lower peak concentration (Cmax) than those without, but overall drug exposure (AUC) was not altered. Cmax and AUC were not influenced by administration route. A trend towards higher Cmax on postoperative day 3 than on postoperative day 1 was noted, although AUC was not altered. Single-dose RAD coadministration did not affect steady-state CsA pharmacokinetics. RAD was well tolerated and caused few drug-related adverse effects. RAD administration did not increase infection rates or produce clinically significant changes in laboratory parameters. Conclusions. In de novo liver transplant recipients, the overall extent of RAD absorption was not influenced by bile diversion, administration route, or time of administration. CsA pharmacokinetics were not affected by single-dose RAD coadministration. RAD capsules administered in single doses of 7.5 mg were well tolerated and safe.

Administration, Oral↗
PubMed2001

Health education groups for caregivers in an HMO.

The short-term effectiveness of a Health Education Group (HEP) intervention program for spouses of frail older adults was compared to the usual care (UC) offered to the spouses of frail older persons in a staff model health maintenance organization. HEP is a multicomponent group program offered in eight weekly, two-hour group sessions, and ten monthly, two-hour follow-up group sessions. It includes emotion-focused and problem-focused coping strategies, education, and support. One-hundred and five spouses were recruited and randomly assigned to HEP (n = 58) or UC (n = 47). Spouse caregivers and care recipients were assessed within two weeks of intervention and within two weeks after the completion of the eight weekly group meetings. The results indicate that, for caregivers, HEP was more effective than UC in reducing depression, maintaining social integration, increasing effectiveness in solving pressing problems, increasing knowledge of community services and how to access them, changing caregivers' feelings of competence, and the way they respond to the care giving situation. No significant differences, however, were found between care recipients in the two arms of the study on any of the outcome measures.

Aged↗
PubMed2001

Species-specific PCR for the identification of ovine, porcine and chicken species in meta and bone meal (MBM).

BSE, first identified in the UK in 1986 is thought to have arisen from feeding scrapie infected Meat and Bone Meal (MBM), produced under sub-optimal conditions, to cattle. For quality and safety reasons there is a requirement for a good analytical test for the surveillance of processed MBM. This study describes species-specific PCR assays for the identification of ovine, porcine and poultry species in MBM. A comparison between two distinct DNA extraction methods, i.e. the silicaguanidiumthiocyanate DNA isolation procedure and a commercial DNA extraction kit, is also presented. Application of this technology to species identification in industrial MBM was investigates as part of this study.

Animal Feed↗
PubMed2001

Functional consequences of mutations in the MODY4 gene (IPF1) and coexistence with MODY3 mutations.

AIMS/HYPOTHESIS: The aim of this study was to examine the putative role of mutations in the insulin promoter 1 (IPF1) gene in early-onset diabetes. METHODS: We carried out mutation screening of the IPF1 gene in 115 Scandinavian families with at least two members with onset of diabetes younger than 40 years. The allele frequencies were also tested in 183 unrelated patients with late-onset Type II (non-insulin-dependent) diabetes mellitus and in 92 non-diabetic control subjects. RESULTS: Two novel IPF1 variants (G212R and P239Q) and one previously reported (D76N) IPF1 variant were identified in the 115 families (3.5%). The D76N variant was found in one MODY3 family (S315fsinsA of HNF1alpha) and also in two families with late-onset Type II diabetes. The P239Q variant was identified in two families with early-onset diabetes including one with MODY3 (R272C of HNF1alpha) and in three families with late-onset Type II diabetes. Despite the fact that the variants did not segregate completely with diabetes, the non-diabetic carriers of the IPF1 variants had increased blood glucose concentrations (p < 0.05) and reduced insulin:glucose ratios (p < 0.05) during an oral glucose tolerance test compared with non-diabetic family members without these variants. In addition, when the G212R and P239Q variants were expressed in cells without IPF1 i.e.. Nes2y cells, both variants showed about a 50% reduction in their ability to activate insulin gene transcription compared to wild-type IPF1, as measured by reporter gene assay. CONCLUSION/INTERPRETATION: Although mutations in the IPF-1 gene are rare in early- (3.5 %) and late-onset (2.7 % ) Type II diabetes, they are functionally important and occur also in families with other MODY mutations.

Aged↗
PubMed2001

Long-term results of a prospective surgical trial comparing 2 cm vs. 4 cm excision margins for 740 patients with 1-4 mm melanomas.

BACKGROUND: The Intergroup Melanoma Surgical Trial began in 1983 to examine the optimal surgical margins of excision for primary melanomas of intermediate thickness (i.e., 1-4 mm). There is now a median 10-year follow-up. METHODS: There were two cohorts entered into a prospective multi-institutional trial: (1) 468 patients with melanomas on the trunk or proximal extremity who randomly received a 2 cm or 4 cm radial excision margin and (2) 272 patients with melanomas on the head, neck, or distal extremities who received a 2 cm radial excision margin. RESULTS: A local recurrence (LR) was associated with a high mortality rate, with a 5-year survival rate of only 9% (as a first relapse) or 11% (anytime) compared with an 86% survival for those patients who did not have a LR (P < .0001). The 10-year survival for all patients with a LR was 5%. The 10-year survival rates were not significantly different when comparing 2 cm vs. 4 cm margins of excision (70% vs. 77%) or comparing the management of the regional lymph nodes (observation vs. elective node dissection). The incidences of LR were the same for patients having a 2 cm vs. 4 cm excision margin regardless of whether the comparisons were made as first relapse (0.4% vs. 0.9%) or at anytime (2.1% vs. 2.6%). When analyzed by anatomic site, the LR rates were 1.1% for melanomas arising on the proximal extremity, 3.1% for the trunk, 5.3% for the distal extremities, and 9.4% for the head and neck. The most profound influence on LR rates was the presence or absence of ulceration; it was 6.6% vs. 1.1% in the randomized group involving the trunk and proximal extremity and was 16.2% vs. 2.1% in the non-randomized group involving the distal extremity and head and neck (P < .001). A multivariate (Cox) regression analysis showed that ulceration was an adverse and independent factor (P = .0001) as was head and neck melanoma site (P = .01), while the remaining factors were not significant (all with P > .12). CONCLUSION: For this group of melanoma patients, a local recurrence is associated with a high mortality rate, a 2-cm margin of excision is safe and ulceration of the primary melanoma is the most significant prognostic factor heralding an increased risk for a local recurrence.

Humans↗
PubMed2001

Gross and histologic characteristics of laparoscopic injuries with four different energy sources.

OBJECTIVE: To compare the gross and histologic effects of bipolar and monopolar cautery, ultrasonic scalpel, and CO(2) laser on porcine ureter, bladder, and rectum. DESIGN: Experimental prospective study. SETTING: Cleveland Clinic Foundation Animal Research Laboratory, Cleveland, Ohio. ANIMAL(S): Nonpregnant adult female pigs. INTERVENTION(S): The rectum, bladder, and ureters of 12 female pigs were injured with four different laparoscopic energy sources. MAIN OUTCOME MEASURE(S): Gross measurements of injured tissue and histologic analysis of the depth of the tissue injury. RESULT(S): Gross assessment results were that monopolar injuries of the bowel and bladder were significantly longer than ultrasonic injuries (P<0.01). Injuries were generally manifest as coagulative denaturation of collagen bundles. This resulted in an eosinophilic homogenization of tissue. Nuclei were retained in the injured tissue, although in most cases they had a pyknotic, streamed appearance. The CO(2) laser caused no deep-tissue injury. CONCLUSION(S): Laparoscopic energy sources injure tissue differently. Monopolar cautery appears to have the most lateral spread of thermal energy. The CO(2) laser appears to cause the least deep-tissue injury.

Animals↗