Biomedical subjects

P Mitchell

Publications and source records attributed to P Mitchell.

At least 199 records · Page 11Linked to original sources

PubMed1999

Diabetic retinopathy after combined kidney-pancreas transplantation.

Diabetic retinopathy (DR) is amenable to good diabetic control; however, only successful pancreas transplantation can achieve sustained normoglycaemia. The aim of this long-term study was to examine the course of DR in insulin-dependent diabetic recipients of a simultaneous kidney and pancreas transplant (SPK). Successful SPK recipients (n = 46) and failed pancreas transplant with a functioning kidney transplant (n = 8) were assessed by baseline and regular post-transplant ophthalmic examinations (n = 432) for up to 10 yr after SPK. At the time of SPK (n = 108 eyes), the mean duration of diabetes was 25 +/- 7 yr, ten eyes were blind, and 79% of eyes had advanced DR that had panretinal laser (panretinal photocoagulation, PRP. Successful SPK recipients had normal glucose control with a mean HBA1C of 5.2 +/- 0.6%. DR remained stable in 75% of both the study and control groups, with no difference between groups. The DR mostly evolved towards inactive proliferative DR. After SPK, 14% of non-blind eyes showed improvement of DR, 76% remained stable and 10% progressed. Early vitreous haemorrhage occurred in 6.1% of eyes, and was related to established DR. Cataract of all types increased after transplantation (p < 0.01), which reduced visual acuity (VA) in affected eyes. The mean overall VA remained unchanged for the study duration. In summary, uremic patients from diabetic nephropathy had a high prevalence of severe proliferative DR and blindness at the time of presentation for SPK. This was subsequently stabilised to inactive proliferative DR by appropriate laser therapy followed by metabolic control achieved by SPK.

Cataract↗

PubMed1999

Children's ability to infer utterance veracity from speaker informedness.

Children between the ages of 3 years 7 months and 6 years 5 months experienced a contradiction between what they knew or guessed to be inside a box and what they were told by an adult. The authors investigated whether children believed what they were told by asking them to make a final judgment about the box's content. Children tended to believe utterances from speakers who were better informed than they themselves were and to disbelieve those from less well-informed speakers, with no age-related differences. This behavior implies an understanding of the speaker's knowledge and suggests that children can learn from oral input while being appropriately skeptical of its truth. Children also gave explicit knowledge judgments on trials on which no utterances were given. Performance on knowledge trials was less accurate than, and unrelated to, performance on utterance trials. Research on children's developing explicit theory of mind needs to be broadened to include behavioral indexes of understanding the mind.

Adult↗

PubMed1999

Anterior ischaemic optic neuropathy in a patient with optic disc drusen.

BACKGROUND: Although visual field defects are well-known complications of optic disc drusen, reduction in visual acuity with this condition is rare. METHOD/RESULTS: We report on a 68-year-old male with bilateral optic disc drusen who presented with monocular loss of vision in the right eye associated with an inferior altitudinal visual field defect and signs consistent with acute anterior ischaemic optic neuropathy, confirmed on fluorescein angiography. He also had a left inferior nasal step, but no evidence of glaucomatous cupping. The disc drusen were documented clinically and on B scan ultrasound and computed tomography. CONCLUSIONS: The diagnosis of acute anterior ischaemic optic neuropathy should be considered in patients with optic disc drusen who present with reduced visual acuity, particularly when the visual loss has been acute and non-progressive and is associated with altitudinal field loss and characteristic fluorescein angiography signs.

Aged↗

PubMed1999

Use of eye care services by older Australians: the Blue Mountains Eye Study.

PURPOSE: To assess utilization of eye care services in an older Australian population. METHODS: The Blue Mountains Eye Study examined 3654 permanent residents aged 49 years or older from two New South Wales postcode areas. At interview, we collected information about past attendance to eye care practitioners, demographic and socio-economic status variables and past medical and eye history. Full-time optometric and part-time ophthalmic services were available in this community. RESULTS: Almost all participants (99%) had seen either an ophthalmologist or optometrist in the past, with 62, 27, 7 and 3% having last attended in the last 2, 2-5, 5-10 and > 10 years, respectively. Among those participants (2251) who had been seen in the last 2 years, 50.2% (1131) last saw an ophthalmologist, 48.6% (1094) last saw an optometrist and 26 (1.2%) could not state whom they saw. After adjusting for age and sex, factors statistically significantly associated with attending an ophthalmologist included older age, female gender, higher socio-economic status, moderate to high myopia and presence of systemic disease (diabetes, hypertension) or any significant eye pathology. Factors statistically significantly associated with attending an optometrist were younger age, living alone, not currently married, being able to go out alone, having better presenting visual acuity, hyperopia and absence of diabetes or significant eye pathology, including moderate to high myopia. CONCLUSIONS: Findings from this study indicate that whether people use eye care services and whom they visit is mainly driven by need factors. Although there was considerable overlap, this study found relatively appropriate utilization of eye care services by this population.

Age Distribution↗

PubMed1999

Sub-grouping non-melancholic major depression using both clinical and aetiological features.

OBJECTIVE: In previous papers we have considered the extent to which two contrasting analytic approaches, examining reported clinical symptom variables alone and aetiological variables alone, assist definition of subgroups of non-melancholic major depression. Here, we address the same objective but combine both sets of variables, and contrast the combined solution with each of the contributing ones. METHOD: We study a sample of 185 subjects with a putative non-melancholic major depressive disorder, with analyses involving 13 aetiological and 38 symptom variables. RESULTS: A four-class subgrouping was derived by use of a cluster analytic technique, with 'neurotic depression', non-anxious 'depressed', 'situational' and 'residual' groups. The largest group comprised 'neurotic depression' subjects, with characteristics compatible with a spectrum disorder encompassing both clinical features as well as an underlying temperament and personality style marked by anxiety. CONCLUSIONS: Comparative advantages and properties of the three differing analytic approaches to defining 'meaningful' non-melancholic major depressive subgroupings are considered. As a 'neurotic depressive' class has been consistently identified across those three approaches, but with quite varying numbers of subjects circumscribed, it is clearly a 'fuzzy' entity which may benefit from a dimensional approach to its measurement. As many of the non-melancholic groupings appear secondary to a substantive predisposing factor such as anxiety or disordered personality functioning, the clinical importance and treatment utility in identifying and circumscribing such classes are clearly supported.

Adult↗

PubMed1999

Are the newer antidepressant drugs as effective as established physical treatments? Results from an Australasian clinical panel review.

OBJECTIVE: The aim of this study was to determine, in a clinical panel sample, the extent to which patients with depression (and melancholic and non-melancholic subtypes) judged the effectiveness of previously received antidepressant treatments, particularly the comparative effectiveness of the older and newer antidepressant drugs. METHOD: Twenty-seven Australasian psychiatrists assessed 341 non-psychotic depressed patients and rated the extent to which previous antidepressant treatments had been effective. Patients were assigned to 'melancholic' and residual 'non-melancholic' categories by two processes (DSM-IV decision rules, and a cluster analysis-derived allocation) and treatment effectiveness examined within each category. RESULTS: Electroconvulsive therapy (both bilateral and unilateral) was judged as highly effective by both melancholic and non-melancholic patients. Antipsychotic medication similarly rated highly (but was judged as more effective by the non-melancholic than melancholic patients). The tricyclics and irreversible monoamine oxidase inhibitors (MAOIs) were rated as more effective by the whole sample than several newer antidepressant classes (including the selective serotonin re-uptake inhibitors [SSRIs], venlafaxine, mianserin and moclobemide), whether effectiveness was examined dimensionally or categorically. Comparison of the overall tricyclic and SSRI classes indicated that any superior tricyclic effectiveness was specific to the melancholic subjects. CONCLUSIONS: Despite methodological limitations intrinsic to such clinical panel data, the judged greater effectiveness of the older antidepressants (tricyclics and irreversible MAOIs) for melancholic depression is of importance. If valid, such data are of intrinsic clinical relevance but also have the potential to inform us about the neurobiological determinants of 'melancholia' and pharmacological actions which contribute to its effective treatment.

Antidepressive Agents↗

PubMed1999

Complication of a venous wallstent.

A case is reported here of effort-related thrombosis of the axillary and subclavian veins (Paget-Schrotter syndrome) treated primarily with a combination of thrombolysis, percutaneous balloon angioplasty (PTA) and stent insertion, but without immediate rib resection. The subsequent course was complicated by fracture of the stent, managed by first rib resection.

Adult↗

PubMed1999

Endocrine effects, efficacy and tolerability of a 10.8-mg depot formulation of goserelin acetate administered every 13 weeks to patients with advanced prostate cancer.

OBJECTIVE: To determine the endocrine effects, efficacy and tolerability of a 10.8-mg depot formulation of Zoladextrade mark (goserelin acetate, Zeneca Pharmaceuticals, Wilmington, Delaware, USA), a luteinizing hormone-releasing hormone agonist analogue, when administration was extended from every 12 weeks to every 13 weeks in patients with advanced prostate cancer. PATIENTS AND METHODS: Between July 1995 and May 1996, 59 patients with either locally advanced (T3 or T4) or metastatic prostate cancer were enrolled in an open-label, multicentre trial. Primary efficacy endpoints were testosterone measurements, and assessments of prostate specific antigen (PSA) response, subjective and objective response. Quality of life (QoL) was a secondary efficacy endpoint. RESULTS: Mean testosterone concentrations decreased to < 0.3 microgram/L by week 4 and remained so for the duration of treatment. There were no statistically significant differences in mean testosterone levels between weeks 12 and 13, or weeks 25 and 26. Serum testosterone suppression was adequate in all 58 evaluable patients at week 13, and 51 of 52 (98%) patients at week 26. Of the 58 evaluable patients, 52 (90%) had a PSA response. A subjective response was recorded for six of 11 evaluable patients. Of 58 patients evaluable for objective response, 46 (79%) had a partial response, three (5%) had stable disease and nine (16%) had objective progression. Except for a significant (P=0.014) decrease in overall sexual interest, QoL was unchanged during therapy. The most common side-effects, regardless of causality, were hot flushes (67%), pain (31%) and pelvic pain (22%). Mild injection-site complaints occurred with only three of 221 (1.4%) depot injections. CONCLUSIONS: Zoladextrade mark 10.8-mg depot, administered every 13 weeks to patients with advanced prostatic cancer, is well tolerated, provides adequate suppression of serum testosterone and produces PSA, subjective and objective responses.

Aged↗

PubMed1999

Plasma fibrinogen and other cardiovascular disease risk factors and cataract.

PURPOSE: To determine whether associations exist between cataract and established cardiovascular risk factors (other than smoking) - hypertension, body mass index, serum lipids and plasma fibrinogen. METHODS: The Blue Mountains Eye Study is a large (n=3654) population-based cross-sectional study conducted among people aged 49-97 years residing in the Blue Mountains, a region west of Sydney, Australia. Risk factor data were collected using standardised clinical procedures. Lens photographs were taken and graded for presence and severity of cortical, nuclear, and posterior subcapsular cataracts. RESULTS: Cortical cataract was associated with a history of myocardial infarction, higher plasma fibrinogen, and higher serum cholesterol. Nuclear cataract was associated with a higher platelet count but hypertension was associated with lower prevalence of nuclear cataract. Posterior subcapsular cataract was associated with higher plasma fibrinogen and lower body mass index. Some of these associations appeared to be stronger in women than in men: fibrinogen and cortical cataract and body mass index and posterior subcapsular cataract. CONCLUSIONS: Several risk factors for cardiovascular disease are associated with presence of cataract, perhaps explaining the observation in several studies that people with cataract have increased mortality rates. The possibility of strong associations between plasma fibrinogen and cataract merits further epidemiological and laboratory research.

Aged↗

PubMed1999

Third ventriculostomy in normal pressure hydrocephalus.

Improvement in three out of four cases of normal pressure hydrocephalus after third ventriculostomy is reported. Pre- and postoperative ventricular pressure recording suggested that this improvement may be occurring in the absence of an improvement in ventricular pressures. Third ventriculostomy may relieve periventricular tissue stress and thus improve local blood flow, which is a likely mechanism in the syndrome of normal pressure hydrocephalus.

Aged↗

PubMed1999

Subtyping depression: testing algorithms and identification of a tiered model.

We seek to distinguish psychotic, melancholic, and nonmelancholic depression by clinical features and to test varying algorithm models to determine optimal criteria sets. We report a study of 269 depressed inpatients and outpatients. A latent class analysis (LCA) of 16 clinical features allowed for specificity or overrepresentation of features to be examined across the three classes. Varying algorithm models for distinguishing melancholic and nonmelancholic depression, involving endogeneity symptoms and observer-rated psychomotor disturbance (PMD) were compared. Psychotic depression was readily distinguished by the specific presence of psychotic features, and PMD was most severe in this class. Melancholic depression was most clearly distinguished from the residual nonmelancholic class by the presence of PMD. Although some endogeneity symptoms were overrepresented in the melancholic class, their specificity was unimpressive. An algorithm involving PMD components alone was highly efficient in discriminating LCA classes and, more importantly, superior to DSM-IV decision rules when examined against a range of clinical validators of melancholia. Subtyping appears assisted by a hierarchical model, based on a small set of features. The move from nonmelancholic to melancholic depression appears defined by a tier of observably rated PMD, whereas the move from melancholic to psychotic depression is determined by a tier of psychotic features and contributed to by significantly higher levels of PMD.

Adult↗

PubMed1999

Factors associated with use of community support services in an older Australian population.

OBJECTIVE: To assess prevalence and risk factors associated with use of community support services in a representative older Australian population. METHODS: The Blue Mountains Eye Study surveyed 3,654 people aged > or = 49 years, 82.4% of eligible residents from an area west of Sydney during 1992-94. Questions about use of community support services were asked during face-to-face interview. Information on marital and living status, socio-economic status measures, past medical history and self-ranked health status were also collected. RESULTS: 186 (5.4%) persons including 124 women (6.3%) and 62 men (4.2%) reported regular use of community support services, including Meals-on-Wheels (n = 52), Home Care (n = 147) or visits from a community nurse (n = 63). All three services were used by 17 persons and two services by 42 persons. There was a marked age-related increase in use of services from 1.8% in persons aged < 60 years to 25.3% in persons aged 80+ years. Factors significantly associated with use of community services in a multivariate model were: age (OR 1.7 per age decade), living alone (OR 2.5), walking disability (OR 4.1), visual impairment (OR 3.0), stroke history (OR 2.2), arthritis history (OR 1.8), low perceived health status (OR 1.7), cancer history (OR 1.7) and a history of any falls in the past 12 months (OR 1.6). CONCLUSIONS: Our study has found a wide range of health-related factors that impact on the use of community support services, particularly conditions causing difficulty in walking. IMPLICATIONS: These data may assist health planners in identifying target populations for the provision of community support services.

Age Distribution↗

PubMed1999

Prevalence and socio-demographic predictors of dietary goal attainment in an older population.

OBJECTIVE: To describe the measured dietary intakes and anthropometry of a large, free-living population of middle-aged and older Australians who participated in the Australian Blue Mountains Eye Study (BMES), and to identify the socio-demographic characteristics associated with attainment or non-attainment of dietary goals. METHOD: Anthropometry and dietary intakes were compared with current population dietary goals and Recommended Dietary Intakes for 2,873 people (79% of eligible residents) aged > or = 49 years who participated in the BMES. Nutrient intakes were measured by a validated food frequency questionnaire. RESULTS: Nutrients for which mean intakes deviated most from nutrition goals included: percentages of energy from total and saturated fat, carbohydrate and alcohol (men), as well as absolute intakes of calcium, zinc and fibre. More than half the men (60%) and women (54%) were overweight or obese. Several micro-nutrient goals were more likely to be met in households where the respondents and/or their spouses were independent. Married men were more likely to meet goals for fibre and iron, but less likely to meet the goal for cholesterol. Several goals were more likely to be met by men and women who had qualifications after leaving school, those with higher job status and non-pensioners, suggesting an socio-economic status dimension. CONCLUSIONS AND IMPLICATIONS: These results indicate that over- rather than under-nutrition is more prevalent among community-dwelling older people, although under-nutrition should not be overlooked. Particular sub-groups that are less likely to meet some dietary goals may require targeting in community nutrition interventions.

Age Distribution↗

PubMed1999

Embolic occlusion of the blood supply to uterine myomas: report of 2 cases.

Uterine myomas are the most common tumours of the female genital tract and with menorrhagia provide the most common indications for hysterectomy. Whilst myomectomy is a surgical alternative, it is associated with greater morbidity and a higher blood transfusion rate. Arterial embolization of myomas is a nonsurgical treatment option that can be performed as an outpatient procedure, is cheaper than myomectomy, permits preservation of reproductive potential, and may not only be associated with less morbidity than myomectomy but also may not cause adhesions which could compromise fertility. This paper details 2 cases treated by this technique.

Adult↗

PubMed1999

The predictive value of endometrial stripe thickness in patients with suspected ectopic pregnancy who have an empty uterus at ultrasonography.

UNLABELLED: Prior research suggests that, in patients with empty uteri at ultrasonography, endometrial stripe thickness may be predictive of ectopic pregnancy or the likelihood of obtaining chorionic villi after a dilatation and evacuation procedure (D+E). However, it is unclear whether the predictive value of endometrial stripe thickness is confined to patients with low beta-human chorionic gonadotropin (beta-hCG) values. OBJECTIVE: To determine whether endometrial stripe thickness is predictive of the risk of ectopic pregnancy or the likelihood of obtaining chorionic villi after D+E in patients with beta-hCG values >1,000 mIU/mL or < or =1,000 mIU/mL. METHODS: In an urban academic ED, the authors conducted a retrospective chart review of consecutive ED patients from August 1991 to August 1997 with abdominal pain or vaginal bleeding, a positive beta-hCG value, and an empty uterus by transvaginal ultrasound examination. Patients were divided into four groups-group 1: endometrium thin, beta-hCG value < or =1,000 mIU/mL; group 2: endometrium thick, beta-hCG value < or =1,000 mIU/mL; group 3: endometrium thin, beta-hCG value >1,000 mIU/ mL; and group 4: endometrium thick, beta-hCG value >1,000 mIU/mL. The secondary analysis was limited to patients who had a D+E performed within 48 hours of the ED visit. The risks of ectopic pregnancy and the likelihoods of obtaining chorionic villi after D+E were compared using chi-square or Fishers' exact test where appropriate, with a p-value of 0.05 being significant. RESULTS: 224 patients were enrolled in the initial analysis. Intergroup differences in the frequency of ectopic pregnancy were of borderline significance (p = 0.08). However, when the comparison was limited to the groups with beta-hCG values < or =1,000 mIU/mL, the predictive value of endometrial stripe thickness reached statistical significance (group 1: 27/99 [27%], group 2: 2/28 [7%], p = 0.05). 79 patients had a D+E performed. Intergroup differences in the rate of obtaining chorionic villi were significant (p = 0.002). Group 1 had the lowest frequency of having chorionic villi identified (4/26 [15%]) and was the only group in which villi were obtained in fewer than 50% of cases. CONCLUSION: Endometrial stripe thickness may be predictive of the risk of ectopic pregnancy and the likelihood of obtaining chorionic villi at D+E. However, its predictive value appears to be confined to patients with beta-hCG values < or =1,000 mIU/mL.

Academic Medical Centers↗

PubMed1999

Normal intrauterine pregnancy is unlikely in patients who have echogenic material identified within the endometrial cavity at transvaginal ultrasonography.

UNLABELLED: In first-trimester patients with abdominal pain or vaginal bleeding, pelvic ultrasonography (US) is often performed to assess the status of the pregnancy. Identification of echogenic material within the endometrial cavity in the absence of a gestational sac has been attributed to the presence of either retained products of conception or clotted blood. However, to the authors' knowledge, no study has directly addressed whether this finding reliably excludes the diagnosis of a normal intrauterine pregnancy (IUP). OBJECTIVE: To determine whether the identification of echogenic material within the endometrial cavity at transvaginal US excludes the diagnosis of a normal IUP. METHODS: Data were collected retrospectively from August 1991 to August 1997 on consecutive urban teaching hospital ED patients with abdominal pain or vaginal bleeding who had a transvaginal US performed during the ED visit that demonstrated echogenic material within the endometrial cavity. Patients were excluded if they had a dilatation and evacuation (D + E) procedure performed prior to the exclusion of a normal IUP by other means [open cervical os, falling quantitative beta--human chorionic gonadotropin (beta-hCG) values, a progesterone value < 5.0 ng/mL or beta-hCG > 3,000 mIU/mL] or if they were lost to follow-up. Patients were followed until a final diagnosis was ultimately determined. RESULTS: A total of 83 patients with echogenic material were identified. Of these, three patients were excluded because a D + E was performed prior to an IUP being excluded by other means, and two patients were lost to follow-up. Of the 78 enrolled patients, none had a final diagnosis of normal IUP. Ectopic pregnancy was confirmed in nine patients, five of whom had no adnexal or cul de sac findings to suggest this diagnosis. CONCLUSION: In symptomatic patients who have echogenic material but no gestational sac visualized within the endometrial cavity at US, the likelihood of a normal IUP is low.

Chorionic Gonadotropin, beta Subunit, Human↗

PubMed1999

The utility of a dilatation and evacuation procedure in patients with symptoms suggestive of ectopic pregnancy and indeterminate transvaginal ultrasonography.

OBJECTIVES: To ascertain the overall frequency of obtaining chorionic villi (CV) in patients with indeterminate transvaginal ultrasound (US) examinations who have had a dilatation and evacuation (D+E) procedure performed, to determine whether the frequency of obtaining CV is dependent on whether the endometrial cavity is empty at US, and to determine the likelihood of ectopic pregnancy in patients without CV after D+E and with or without an empty endometrial cavity at US. METHODS: A retrospective review was made of consecutive ED patients presenting to an urban teaching hospital from August 1991 through August 1997 with abdominal pain or vaginal bleeding and a positive beta-human chorionic gonatropin (beta-hCG) test. Patients who had a transvaginal US that was read as indeterminate (no extrauterine findings of ectopic pregnancy, and no intrauterine fetal pole or yolk sac) and who had a D+E performed within 48 hours of the ED visit were eligible. US exams were subdivided into two groups, those with empty endometrial cavities and those with endometrial cavities that contained fluid, echogenic material, or sac-like structures. The presence or absence of CV was based on the official pathology report. Patients were excluded if pathology results were not available. RESULTS: A total of 255 patients met eligibility criteria. Of these, pathology results were not available for five patients. Of the remaining patients, 177 of 250 (70.8%: 95% CI = 64.7% to 76.3%) had CV identified in the pathology specimen. The difference in the frequencies of obtaining CV in those with empty endometrial cavities (35/78; 44.9%: 95% CI = 34% to 56%) vs. those without empty endometrial cavities (142/172; 82.6%: 95% CI = 76% to 88%) was significant (p<0.001). Ectopic pregnancy was diagnosed in 17 of 42 (40.0%) with empty uteri at US and no CV at pathology vs 5 of 26 (19.2%) in whom the uterus was not empty and no CV were obtained (p = 0.07). CONCLUSION: In symptomatic patients with indeterminate transvaginal ultrasound exams, CV will be identified after D+E in approximately 70% of cases. Although CV were found with increased frequency when the endometrial cavity was not empty, still almost half of the patients with empty uteri had villi identified. Finally, although the frequency of ectopic pregnancy was higher in the patients with empty uteri and no CV at D+E, vs. those without an empty uterus and no CV, this difference did not reach statistical significance.

Abortion, Therapeutic↗

PubMed1999

Expression of fibroblast growth factor family during postnatal skeletal muscle hypertrophy.

The potential role of the fibroblast growth factor (FGF) family during stretch-induced postnatal skeletal muscle hypertrophy was analyzed by using an avian wing-weighting model. After 2 or 11 days of weighted stretch, anterior latissimus dorsi (ALD) muscles were, on average, 34 (P < 0.01) and 85% (P < 0.01) larger, respectively, than unweighted ALD control muscles. By using quantitative RT-PCR, FGF-1 mRNA expression was found to be significantly decreased in ALD muscles stretched for 2 or 11 days. In contrast, FGF-4 and FGF-10 mRNA expression was significantly increased 2 days after initiation of stretch. FGF-2, FGF-10, fibroblast growth factor receptor 1, and FREK mRNA expression was significantly increased at 11 days poststretch. Increases in FGF-2 and FGF-4 protein could be detected throughout the myofiber periphery after 11 days of stretch. On a cellular level, FGF-2 and FGF-4 proteins were differentially localized. This differential expression pattern and protein localization of the FGF family in response to stretch-induced hypertrophy suggest distinct roles for individual FGFs during the postnatal hypertrophy process.

Animals↗