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Biomedical subjects

J McBride

Publications and source records attributed to J McBride.

At least 37 records · Page 2Linked to original sources
PubMed1999

The relationship between dynamic, isokinetic and isometric strength and bone mineral density in a population of 45 to 65 year old women.

This study investigated the relationship between age, lumbar spine bone mineral density (LS BMD) and muscular strength of peri and postmenopausal women between 45 and 65 years either taking or not taking hormone replacement therapy (HRT). Ninety six women were tested for LS BMD (L2-L4), one repetition maximum (1RM) bench press and squat, maximal voluntary isometric contraction (MVC) of the knee extensors and peak torque of back extensor muscles at a speed of 30 degrees s(-1). Bone and strength data were analysed to evaluate the relationships in incrementing five year age groups and based on groups either taking or not taking HRT. ANOVA revealed significant differences in LS BMD between the 45-49 and 55-59 (F[3,92]=2.6411, p<0.05; -8%) age groups amounting to an annual bone loss of 0.8% for this Australian based population. Non significant LS BMD results were evident after controlling for the influence of age and menopausal status on the groups either taking or not taking HRT. Significant differences between the 45-49 and 60-64 (F[3,92]=2.7463, p<0.05) age groups for 1RM bench press and the 45-49 and 60-64, 50-54 and 60-64, and, 55-59 and 60-64 (F[3,92]=4.2816, p<0.05) age groups for 1RM squat amounting to an 18.8% and 37.5% loss of dynamic upper and lower body strength, respectively. Group correlation coefficients ranged between (r=-0.20 and -0.34, p<0.05) for LS BMD, strength and age. The conclusions demonstrate a concomitant decline in maximal muscle strength and bone density between women 45 and 65 years irrespective of HRT. These results also demonstrate a 50% greater decline in lower body strength compared to upper body strength between women 45 and 65 years.

Absorptiometry, Photon↗
PubMed1999

Culture-amplified detection of dengue virus from serum in an outbreak of dengue fever.

An outbreak of dengue type 2 occurred in North Queensland, Australia, between December 1996 and April 1997. Culture of serum in the Aedes albopictus C6/36 cell line with detection using immunofluorescent staining was compared with a culture-amplified detection system using an immunoperoxidase staining method in a microtiter plate format. A total of 374 serum specimens from individuals during the outbreak were tested. Ninety-five specimens were positive using immunofluorescence and ninety-two were positive using the immunoperoxidase method (sensitivity 91.6%; specificity 98.2%). The immunoperoxidase method is quicker, easier to perform, and does not require the use of an immunofluorescent microscope. The method is more suited to the processing of large numbers of specimens in an outbreak and could be used in endemic areas with limited virological resources.

Adult↗
PubMed1998

Reduction of ornithine decarboxylase antizyme (ODC-Az) level in the 7,12-dimethylbenz(a)anthracene-induced hamster buccal pouch carcinogenesis model.

Ornithine decarboxylase (ODC) activity is elevated in and necessary for oral carcinogenesis, but the mechanism for its deregulation is unclear. Using subtractive hybridization, a 1029 bp full-length cDNA encoding a 222 amino acid open reading frame has been isolated from normal hamster oral keratinocytes. The hamster cDNA is homologous to the human, mouse and rat ornithine decarboxylase antizyme gene (ODC-Az). The hamster ODC-Az gene demonstrated a restriction fragment length polymorphism (RFLP) upon Southern blot analysis comparing normal and tumor hamster genomic DNA. Northern blot analysis revealed that normal hamster oral keratinocytes express readily detectable level of ODC-Az mRNA. Malignant oral keratinocytes demonstrate reduced expression of the ODC-Az mRNA. In contrast, malignant hamster oral keratinocytes have elevated ODC mRNA levels and lengthened ODC protein half-life when compared to the normal counterparts. This was corroborated by direct measurement of ODC enzymatic activity. These data support the hypothesis that the reduced and/or loss of expression and function of the ODC-Az gene is an important event for the early de-regulation of cellular proliferation during oral tumor development.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1998

IL-4-dependent regulation of TGF-alpha and TGF-beta1 expression in human eosinophils.

TGFs play important roles in wound healing and carcinogenesis. We have previously demonstrated that eosinophils infiltrating into different pathologic processes elaborate TGF-alpha and TGF-beta1. Eosinophils infiltrating hamster cutaneous wounds were found to express TGFs sequentially. In this study, we examined the biologic mediators that may regulate the expression of TGF-alpha and -beta1 by eosinophils. Eosinophils were isolated from the peripheral blood of healthy donors and cultured in the absence or presence of IL-3, IL-4, and IL-5. Cells were analyzed by in situ hybridization and immunohistochemistry. Supernatants from these cultures were assayed for secreted TGF-alpha and TGF-beta1 using TGF-specific ELISAs. IL-3, IL-4, and IL-5 independently up-regulated TGF-beta1 mRNA and product expression by eosinophils in all donors. Interestingly, TGF-alpha production by eosinophils was up-regulated by IL-3 and IL-5 but was down-regulated by IL-4. Consistent with the ability of IL-4 to regulate eosinophil responses, IL-4 signaling molecules are present in human eosinophils. The observation that IL-4 can differentially regulate the expression of TGF-alpha and TGF-beta1 suggests that IL-4 may serve as a physiologic molecular switch of TGF expression by the infiltrating eosinophils in wound healing and carcinogenesis.

Adult↗
PubMed1998

Optimized conditions for gene transfection into the human eosinophilic cell line EoL-1 by electroporation.

Eosinophils are emerging as an increasingly important cell in the immunoregulatory network of normal and pathological processes. No studies has yet described optimized experimental strategies to transfect DNA into human eosinophils. Using a frequently employed in vitro model of human eosinophil, the EoL-1 cells, we now described the optimal transfection of DNA into these cells by electroporation. Our results indicate that electroporation can efficiently and reproducibly transfect DNA into EoL-1 cells. Optimal electroporation conditions consist of the use of 1 X RPMI medium 1640 with 10% FBS, voltage setting at 275 V, 1150 microF capacitance, 40 mg of DNA and 4.0 X 10(7) cells/ml per electroporation in a total volume of 0.5 ml in 0.4 cm gap cuvettes. These conditions may be a useful protocol for transfecting eosinophil cell lines.

DNA↗
PubMed1998

Cloning, mapping, expression, function, and mutation analyses of the human ortholog of the hamster putative tumor suppressor gene Doc-1.

doc-1 is a putative tumor suppressor gene isolated and identified from the hamster oral cancer model. Here, we report the molecular cloning and the functional characterization of the human ortholog of the hamster doc-1 gene. Human doc-1 cDNA is 1.6 kilobase pairs in length and encodes for a 115-amino acid polypeptide (12.4 kDa, pI 9. 53). Sequence analysis showed 98% identity between human and hamster doc-1 protein sequences. DOC-1 is expressed in all normal human tissues examined. In oral keratinocytes, expression of DOC-1 is restricted to normal oral keratinocytes. By immunostaining of normal human mucosa, DOC-1 is detected in both the cytoplasm and nuclei of basal oral keratinocytes; while in suprabasilar cells, it is primarily found in the nuclei. Human oral cancers in vivo did not exhibit immunostaining for DOC-1. Like murine DOC-1, human DOC-1 associates with DNA polymerase alpha/primase and mediates the phosphorylation of the large p180 catalytic subunit, suggesting it may be a potential regulator of DNA replication in the S phase of the cell cycle. Using a human doc-1 cosmid as a probe, human doc-1 is mapped to chromosome 12q24. We identified four exons in the entire human doc-1 gene and determined the intron-exon boundaries. By polymerase chain reaction and direct sequencing, we examined premalignant oral lesion and oral cancer cell lines and found no intragenic mutations.

Amino Acid Sequence↗
PubMed1998

The evolutional stage changes in sarcoidosis on gallium-67 scintigraphy.

UNLABELLED: Gallium-67 scintigraphy has been proven as the imaging modality of choice in monitoring the presence of active disease in sarcoidosis. The purpose of this study is to analyze the patterns of evolutional stage changes of sarcoidosis while on steroid therapy by Ga-67 scintigraphy. METHODS: Eighty-six consecutive patients with biopsy-proved sarcoidosis are evaluated by Ga-67 scintigraphy. Thirty-six of 86 patients have had a baseline and one to eight follow-up Ga-67 scintigraphs (total 136 studies). The initial follow-up scintigraphs are obtained on average about 4-12 months after the baseline study. RESULTS: Seventeen of 36 patients (47.2%) are in stage IV at the time of the baseline study. Following their first course of corticosteroid therapy, 13 patients remained in the same stage and activity distribution pattern while 13 patients have shown reversion to other stages, eight patients showed complete remission while two patients became active from inactive stage. CONCLUSION: Evolutional stage changes are seen in 23 patients (63.9%), including eight patients (22.2%) who showed complete scintigraphic remission. The evolutionary stage changes remain quite variable and unpredictable. This, however, should not detract from the usefulness of Ga-67 scintigraphy in the diagnosis and prognostic evaluation of sarcoidosis, particularly when extrapulmonary involvement (Stage IV disease) is present.

Adrenal Cortex Hormones↗
PubMed1998

IL-1 beta and IL-6 in mouse parotid acinar cells: characterization of synthesis, storage, and release.

Synthesis, storage, and secretion of the proinflammatory cytokine interleukin-1 beta (IL-1 beta) and the anti-inflammatory cytokine IL-6 have not been established in normal exocrine gland secretory cells. Parotid glands and isolated acinar cells prepared from BALB/c mice were homogenized for RNA isolation and reverse transcription-polymerase chain reaction (RT-PCR). IL-1 beta and IL-6 enzyme-linked immunosorbent assays (ELISAs) were done on supernatants prepared from mouse parotid acinar cell (MPAC) preparations unstimulated or stimulated between 0 and 10 min with 10(-5) M norepinephrine at 37 degrees C. MPACs were fixed in paraformaldehyde, frozen sectioned for light and electron microscopy, and labeled with antibodies to IL-1 beta and IL-6. Mouse specific riboprobes to IL-1 and IL-6 were used for in situ hybridization. RT-PCR yielded the expected IL-1 (336-bp) and IL-6 (614-bp) mRNA products. By ELISA, stimulated MPACs showed a significant increase in IL-1 beta (P < 0.03) and IL-6 (P < 0.01) release into supernatants by 10 min that paralleled the time course of amylase release. In situ hybridization showed the presence of transcripts for IL-1 and IL-6 in glandular epithelial cells. Gold-labeled IL-1 beta and IL-6 were significantly higher (P < 0.01) in granules than in the nucleus and cytoplasm. This study shows that MPACs synthesize IL-1 beta and IL-6 and release these cytokines from their granules after alpha- and beta-adrenergic stimulation.

Amylases↗
PubMed1998

Physician choice directories: the impact on HMO members' perceptions.

It is a generally held belief that enrolled members of a health maintenance organization (HMO) will be more satisfied with their HMO and physicians if those members have a relationship with a personal physician. Public relations and marketing managers, therefore, in an attempt to encourage the establishment of such relationships, spend significant resources producing physician choice directories for their HMO members. But to what extent do these directories impact members? Do the HMO members read them? If so, do they take advantage of the opportunity to choose a personal physician? And if they do choose, what affect does that choice behavior have on satisfaction levels? The experience of one large, group model HMO suggests that physician choice directories enhance members' confidence in their physicians and their satisfaction with personalized care.

California↗
PubMed1997

Characterization of synthesis and storage of TGF-alpha in rat parotid acinar and intercalated duct cells.

Although the expression and biological role of transforming growth factor-alpha (TGF-alpha) have been explored in a variety of normal cells in mammalian species, little is known about the storage of TGF-alpha in secretory cells of exocrine organs. Parotid glands from four rats were homogenized for RNA isolation followed by reverse transcription-polymerase chain reaction to determine the presence of TGF-alpha message. In situ hybridization using a hamster-specific TGF-alpha riboprobe was done on paraffin sections. Parotid gland and isolated acinar cells were processed for transmission electron microscopy (TEM) and postembedding immunogold labeled for TGF-alpha. Gold particles were counted on approximately 200 granules in 10 acinar cells and in 10 intercalated duct cells. Labeling density was calculated as the number of gold particles per square micrometer +/- SD. Statistical significance was calculated using one-way analysis of variance. Using multiple technologies, we have established that rat parotid acinar and intercalated duct cells synthesize TGF-alpha and store the precursor form of this cytokine in their secretory granules.

Animals↗
PubMed1997

Lothian inter-agency child protection guidelines: impact on a children's NHS trust.

OBJECTIVE: To evaluate the process involved in cases of suspected child abuse within a children's NHS Trust, 6 months after implementation of new inter-agency Child Protection guidelines. DESIGN: Prospective evaluation of case records. SETTING: Four departments within a combined child health trust in Edinburgh. MAIN MEASURES: Review of practice within each department, according to the Inter-Agency guidelines. RESULTS: No standard procedure existed for the child protection process prior to the guidelines. In the first 6 months following implementation of the guidelines, a substantial increase in workload was experienced by community paediatricians. Medical examinations were better co-ordinated, with fewer children receiving repeated, intrusive examinations. However, note keeping was deficient, as 3% of referrals did not appear to be recorded in the case notes. Cross-referencing between departments was variable, with 81% of cases referred to Community Child Health not recorded in hospital case notes. CONCLUSIONS: The Inter-Agency guidelines have resulted in better coordination of the early referral stages. Deficiencies highlighted in this audit are due to record keeping and lack of liaison between departments within a combined children's trust.

Child Abuse↗
PubMed1996

Reduction of post-operative nausea and vomiting with the combination of morphine and droperidol in patient-controlled analgesia.

PURPOSE: To determine whether low doses of droperidol mixed with morphine in patient-controlled analgesia (PCA) would extend the duration of prophylaxis against postoperative nausea and vomiting. METHODS: Healthy women having elective open-abdominal gynaecological surgery consented to this double-blind, placebo-controlled study. Subjects were randomized to receive placebo, or 1 mg droperidol before induction followed by droperidol 0.0 (bolus group), 0.02 (0.02 group), or 0.04 (0.04 group) mg.mg-1 of PCA morphine. Study endpoints included severity of nausea, episodes of vomiting and rescue antiemetic doses, pain, and sedation and were assessed at 1, 2, 4, 8, 12, 16, 20 and 24 hr postoperatively. RESULTS: Seventy-one subjects completed the study. The groups were similar in age, weight, surgical time, pain scores, and morphine used. The 0.04 group had lower mean visual analogue scale scores for nausea (P < 0.05 vs all other groups). The incidence of vomiting was lower in all treatment groups (P < 0.05 for all groups vs placebo). The 0.04 group had lower rescue antiemetic requirements than the bolus group (P < 0.03). Mean sedation scores were low in all groups but were increased with PCA droperidol (P < 0.02). CONCLUSIONS: Droperidol 1 mg before induction of anaesthesia reduces postoperative vomiting. The addition of droperidol 0.04 mg.mg-1 of PCA morphine further reduces (i) severity of nausea and (ii) rescue antiemetic requirements postoperatively. No clinically significant side-effects were attributed to this regimen.

Adolescent↗
PubMed1996

Benefits of indirect impediometry, using Rappaport-Vassiliadis broth, for the detection of Salmonella in processed animal protein.

Four hundred samples of processed animal protein were analysed for the presence of Salmonella using two impediometric methods. The direct method using both Easter and Gibson's, and Ogden's media, as defined in legislation applying throughout the UK, was less selective and sensitive, detecting 30% fewer positive samples than the indirect method using Rappaport-Vassiliadis broth. The indirect method detected 63 positive samples with a false positive rate of less than 10% and about 87% of positive samples were detected less than 12 h after being loaded onto the impedance equipment. Thus the indirect method was superior in terms of performance as well as being a cheaper and simpler methodology for the detection of Salmonella.

Animals↗
PubMed1996

Salivary EGF regulates eosinophil-derived TGF-alpha expression in hamster oral wounds.

Using hamster as an oral wound healing model, we examined eosinophils and their expression of transforming growth factor-alpha (TGF-alpha) and transforming growth factor-beta 1 (TGF-beta 1). Oral wounds healed approximately two times faster than their cutaneous counterparts. Eosinophils infiltrated prominently into oral wounds; however, unlike the dual expression of TGF-alpha and TGF-beta 1 in skin wounds, oral wound-associated eosinophils expressed TGF-beta 1, but not TGF-alpha. Because saliva is present in oral environments and contains epidermal growth factor (EGF) and TGF-alpha, sialoadenectomy was performed in this model to determine whether the lack of TGF-alpha expression by eosinophils in oral wounds is due to the presence of salivary EGF and/or TGF-alpha. We found that eosinophils in sialoadenectomized hamsters did express TGF-alpha during oral wound healing but that such expression was suppressed when EGF was added to their drinking water. Taken together, our findings suggest that eosinophil-derived TGF-alpha and salivary TGF-alpha/ EGF may have complementary roles in contributing to TGF-alpha in oral wound healing.

Animals↗
PubMed1996

Delisting of drugs in Ontario. How attitudes and prescribing strategies of family physicians in the Kingston area changed.

OBJECTIVE: To assess how attitudes and prescribing strategies of family physicians changed when drugs were delisted from the Ontario Drug Benefit formulary. DESIGN: Mailed, self-administered survey. SETTING: Family physicians' offices in Ontario. PARTICIPANTS: All family physicians practising in the Kingston, Frontenac, Lennox, and Addington Health District. MAIN OUTCOME MEASURES: Physicians were presented with six vignettes involving patients receiving a delisted drug. The choices were to recommend the patient pay for the medication, to substitute a drug still listed on the formulary, to make a special request that the medication be covered for this patient, or to offer another option. As well, the physicians were asked to indicate, on a 5-point Likert scale, their opinions regarding the effect of delisting on themselves and their patients. RESULTS: Physicians were most likely to change to a medication that was still on the formulary. Patient sex and ability to pay were factors in physicians' decisions. Physicians believe that the delistings are not likely to have adversely affected patients' health, that noncompliance is a problem because many once-daily formulations have been removed, that suitable alternatives are not always available, and that physicians should have been consulted more before the changes were made. CONCLUSIONS: Physicians usually substitute listed medications for medications that have been delisted. This is especially true for female patients and patients who are unable to pay.

Adult↗
PubMed1995

Deleted in oral cancer-1 (doc-1), a novel oral tumor suppressor gene.

We have identified, isolated, and partially characterized doc-1, a novel cDNA sequence whose activity is consistent with a suppressor of hamster oral carcinogenesis. Doc-1 is an evolutionarily conserved gene exhibiting loss of heterozygosity and marked reduction in expression in malignant hamster oral keratinocytes. The full-length doc-1 cDNA encodes an 87 amino acid product that shows a significant homology to one of the seven novel genes induced in mouse fibroblasts by TNF-alpha. Transfection of the full-length doc-1 cDNA into malignant hamster oral keratinocytes alters the behavior of the recipients in terms of morphology, growth rate, and anchorage-independent growth, suggesting reversion of transformation phenotypes. We propose that doc-1 is a novel tumor suppressor gene in oral cancer development.

Amino Acid Sequence↗