Search PubMed⌕ Search

Biomedical subjects

K Sharples

Publications and source records attributed to K Sharples.

At least 19 recordsLinked to original sources
PubMed2000

Enhanced surveillance of HIV infections in New Zealand, 1996-1998.

AIM: To improve understanding of the HIV epidemic in New Zealand through use of an enhanced voluntary reporting system for new diagnoses of HIV. METHODS: Routine reporting of new HIV diagnoses by the two laboratories that perform confirmatory HIV antibody testing, to the Department of Health and later to the AIDS Epidemiology Group, has been in place since 1985. From January 1996, this was supplemented by a questionnaire about demographic characteristics and circumstances of HIV exposure sent to clinicians requesting the HIV test. RESULTS: From January 1996 to December 1998, 260 new diagnoses of HIV were reported (205 males, 55 females) and extra information was obtained from clinicians for 253 (97.3%) people. HIV diagnosis rate was highest for 'other' ethnicity and similar for European, Maori and Pacific Island ethnic groups. Sexual intercourse between men was the commonest mode of infection (43.5%), followed by heterosexual intercourse (40.0%) and injecting drug use (2.7%). Places of infection were New Zealand (38.5%), Australia (7.7%), 'other' overseas (45.4%) and unknown (8.5%). Heterosexual infections were acquired through contact with a person in or from a high prevalence area (mainly in Africa or Asia) for 86.7% of males and 68.2% of females. Second generation heterosexual transmission was rare. CONCLUSIONS: Introduction of an enhanced surveillance system has been successful. Results confirm continuing spread of HIV in New Zealand amongst men who have sex with men, and suggest low levels of heterosexual and injecting drug use transmission in New Zealand. Of major importance in the occurrence of heterosexual infection is the role of imported HIV.

Adolescent↗
PubMed2000

The optimal use of allopurinol: an audit of allopurinol use in South Auckland.

BACKGROUND: Gout is a common and challenging problem in South Auckland, New Zealand. Allopurinol is widely used but urate reduction remains unsatisfactory. Allopurinol dosing guidelines and a therapeutic range for plasma oxypurinol levels have been published. AIMS: We aimed to determine the appropriateness of allopurinol dosing according to current guidelines and to assess the relationship between plasma creatinine, oxypurinol and urate. In addition, we assessed the clinical usefulness of the oxypurinol level. METHODS: Thirty-one patients, on a stable dose of allopurinol for at least three weeks, had plasma creatinine, urate and oxypurinol measured as part of routine clinical assessment. Relationships between the various methods were examined using regression analysis. Fisher's exact test was used to test associations with categorical variables. RESULTS: Fifty-five per cent of patients were on higher than recommended doses of allopurinol. There was a statistically significant relationship between calculated creatinine clearance and plasma oxypurinol level. Only 50% of patients with a plasma oxypurinol within the therapeutic range (30-100 micromol/L) had a plasma urate < 0.42 mmol/L and this did not increase significantly in the patients with an oxypurinol level > 100 micromol/L. CONCLUSIONS: There is poor adherence to the current recommended dosing guidelines for allopurinol. Creatinine clearance rather than plasma creatinine needs to be used to predict the dose of allopurinol. The current role of the oxypurinol level is to identify non-compliers with allopurinol therapy. We need further research to clarify whether increasing the dose of allopurinol outside the recommended dose range to reach an oxypurinol level of close to 100 micromol/L may be of benefit in those who have not had sufficient urate reduction.

Adult↗
PubMed1997

Patterns of disease and HIV testing at sexually transmitted disease clinics.

AIM: To measure the occurrence of sexually transmitted diseases (STDs) and of HIV testing in a population of STD clinic attenders and the associations of these with age, gender, ethnicity, intravenous drug use, sexual practices and other STDs. METHODS: The study population comprised 8478 new attenders who had blood taken at STD clinics in Auckland and Christchurch between August 1991 and August 1992. Demographic and behavioural information was recorded, along with STD diagnoses and whether or not an HIV test was carried out. These data were analysed by univariate and multivariate methods to determine patterns of disease and voluntary HIV testing. RESULTS: The proportions of the study group with each of the six major STD diagnoses were syphilis 0.8%, gonorrhoea 3.1%, chlamydial infection 11.7%, nonspecific urethritis/cervicitis 12.0%, genital warts 17.4% and genital herpes 6.1%. Gonorrhoea and chlamydial infection were significantly correlated. Both Maori and Pacific Islands ethnicity were significantly associated with the occurrence of bacterial STDs and inversely associated with viral STDs. Twenty-two percent of subjects had voluntary HIV testing at this single visit. Maori were tested at 60% of the European rate and Pacific Islands people at 25-30%. CONCLUSIONS: The profiles of different STDs vary in terms of the sociodemographic and behavioural characteristics of those most often affected. There are major differences in patterns of disease and service use between ethnic groups that require further investigation.

Adolescent↗
PubMed1997

Systematic review of randomized controlled trials comparing laparoscopic with open appendicectomy.

BACKGROUND: The role of laparoscopic surgery in the management of patients with suspected appendicitis is still debated despite a number of recent randomized controlled trials (RCTs). METHODS: A systematic review has been undertaken of all published RCTs comparing laparoscopic appendicectomy with open appendicectomy. Studies were identified through Medline and supplemented with a manual search of relevant journals and meeting abstracts. Data were extracted and analysed according to predefined criteria. RESULTS: Ten studies were identified, seven of which reported results on an intention-to-treat basis. Laparoscopic appendicectomy was associated with a longer operating time (8-29 min), a minimal reduction in hospital stay and, probably, an earlier return to normal activity. It was also associated with a reduced risk of wound infection (odds ratio 2.6) with no increase in other complications. However, bias, particularly resulting from lack of blinding, makes some of these results difficult to interpret. CONCLUSIONS: Laparoscopic appendicectomy was associated with some advantages and no obvious disadvantages, apart from prolonged operating time. Future RCTs should be blinded to minimize bias, document adequate follow-up and analyse results on an intention-to-treat basis.

Adolescent↗
PubMed1996

Juvenile spring eruption: a prevalence study.

AIMS: To measure the prevalence of juvenile spring eruption of the ears in Dunedin primary school aged children. To characterise the population of children affected by juvenile spring eruption in New Zealand. METHODS: Children attending three primary schools were examined for evidence of clinical and preclinical juvenile spring eruption on a single occasion in the late spring. Ear protuberance, hair cover and other factors related to sun exposure were assessed. RESULTS: The overall prevalence of clinical juvenile spring eruption was 6.7% (95% confidence interval = 4.7% to 7.5%). The prevalence in males was 12% (95% CI = 7.3% to 17%). Lack of hair cover and protuberant ears (75th percentile or greater) were strongly associated with clinical juvenile spring eruption. There was no evidence of an association between clinical juvenile spring eruption and skin tone, hair colour, time spent outdoors, sunscreen use, and hat use. CONCLUSION: Juvenile spring eruption is a relatively common dermatological condition among primary school aged children in Dunedin, especially boys.

Child↗
PubMed1993

Outcome of adults with acquired immunodeficiency syndrome in Auckland 1983-9.

AIMS: To assess the survival of Auckland residents diagnosed with AIDS between 1983 and 1989. METHODS: Retrospective case review RESULTS: Sixty nine Auckland residents were diagnosed with AIDS between 1983 and the end of 1989, and were cared for by the infectious disease unit, Auckland Hospital. The overall median survival was 289 days with 48% and 20% surviving at one and two years respectively. Survival was longer among those who were infected through homosexual contact, were younger, and not known to the infectious disease unit prior to the diagnosis of AIDS. Although survival was longer for those diagnosed in 1988 compared to earlier years, it was shorter again for those diagnosed in 1989. Pneumocystis carinii pneumonia, the AIDS defining condition in 63.8% of people, was found less frequently in 1989, and overall was associated with a longer survival than most of the other AIDS-defining diagnoses. A quarter of the people were not known to be infected with HIV prior to the AIDS-defining condition. CONCLUSION: In New Zealand, as in other countries, changes in treatment strategies of people with HIV infection may impinge on the survival of people with AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Position paper: imaging methods for primary renal tumors of childhood: costs versus benefits.

The patterns of disease distribution at diagnosis and during follow-up were cataloged for the primary renal tumors of childhood. These data, derived from more than 1,500 patients, were used to define the most rewarding and cost-effective imaging methods required for patient management. The basic information needed prior to surgery includes whether there is a functioning kidney on the opposite side, and whether there are lung metastases or inferior vena cava thrombi. Simple X-ray examinations and ultrasonography (US) will provide the necessary data. Postoperatively, when the histology is known, examination of the brain (MRI or CT scan) is needed for patients with the rhabdoid tumor and clear cell sarcoma of the kidney (CCSK) who are prone to develop brain lesions; and the skeletal system (bone scan, X-ray skeletal survey) for CCSK and for renal cell carcinoma patients who tend to develop bone metastases. Continuing examination of the lung (chest films) is required for all histologies except perhaps for mesoblastic nephroma, which seldom metastasizes. The opposite kidney needs follow-up (US) for 5 or more years to exclude metachronous involvement if nephrogenic rests are present in either kidney. Sophisticated imaging studies, which cost five times or more than simple X-ray examinations or US, are not warranted routinely, and should be reserved for those cases where simpler, less expensive studies do not suffice for reaching patient management decisions.

Bone Neoplasms↗
PubMed1991

Prognostic factors in nonmetastatic, favorable histology Wilms' tumor. Results of the Third National Wilms' Tumor Study.

A comprehensive statistical analysis of relapses to lung and abdomen and of deaths due to tumor that occurred among 1466 patients with nonmetastatic, favorable histology (FH) Wilms' tumor entered on the Third National Wilms' Tumor Study (NWTS-3) was undertaken. In addition to lymph node involvement, age at diagnosis and tumor size as measured by the weight of the excised specimen were the most important determinants of outcome. The effects of tumor size were most apparent for patients with localized (Stage I) disease; age effects were found for patients with regional (Stage II or III) disease. The presence of microscopic tumor in the margin of surgical resection was an independent predictor of abdominal recurrence and death in the latter group. Although the report of the surgeon of diffuse soilage of the peritoneal cavity from tumor spilled or cut across in the course of nephrectomy was highly correlated with outcome, it was not possible to establish an independent prognostic role for such a finding after adjustment for the aforementioned factors. Patients with intralobar nephrogenic rests (ILNR) had a favorable survival outlook even after accounting for their generally younger ages and lower stages.

Abdominal Neoplasms↗
PubMed1991

Trends in nonmelanoma skin cancer mortality.

Nonmelanoma skin cancer mortality rates for recent decades show a biphasic pattern: from 1950-65 rates decreased; from 1966-86 rates increased. Age standardised mortality rates for 35-74 year old males increased from 1.6 (95% CI, 1.3-1.9) deaths per 100,000 person years in 1966-72 to 2.3 (95% CI, 2.0-2.5) deaths per 100,000 person years in 1980-86. Rates in women were lower but showed a similar percentage increase (46%), between these periods, to that observed for men (44%). The increased mortality from 1966 was presumably a result of increased ultraviolet exposure.

Adult↗
PubMed1990

Better survival after combined modality care for adults with Wilms' tumor. A report from the National Wilms' Tumor Study.

Adults with Wilms' tumor (WT) have had a poor prognosis. More recently, therapies used in children, who have a better outlook, are also being employed for adults. This study was undertaken to see whether adults with WT have benefited. The results of treatment of 27 adults with WT were reported to the National Wilms' Tumor Study (NWTS) from 1979 to 1987. The ages of the 27 adults ranged from 16 to 74 years (median, 24 years). Four had anaplastic WT, and 23 had favorable histology (FH) WT. All but one patient underwent nephrectomy, 21 were given postoperative radiation therapy, and 25 received chemotherapy. The agents used most often included actinomycin D (AMD), vincristine (VCR), and doxorubicin (Adriamycin; ADR). There were six Stage I, five Stage II, four Stage III, 11 Stage IV, and one Stage V patients. The 3-year survival rate is 67%. These results are better than the 24% reported by the NWTS in the past for adults with WT. Analyses of the therapies given to the 27 adults lead to the following recommendations: for Stage I/FH patients, 6 months of postoperative chemotherapy using AMD + VCR without postoperative radiation therapy; and for Stage II, III, and IV/FH, VCR + AMD + ADR for 15 months + 2000 cGy to the tumor bed, 1200 to 1500 cGy to the lungs, 2000 cGy to the liver, and 3000 cGy to other sites as appropriate in patients with metastases at diagnosis.

Adolescent↗
PubMed1989

Prognostic factors for children with recurrent Wilms' tumor: results from the Second and Third National Wilms' Tumor Study.

The characteristics of 367 stage I-IV National Wilms' Tumor Study (NWTS) children who relapsed after initial treatment for unilateral disease in the second and third NWTS trials (NWTS-2 and -3) were analyzed to identify features predictive of survival. Although modifications in initial therapy resulted in a lower rate of first relapse in these two studies compared with NWTS-1, all previously identified prognostic factors after relapse remained statistically significant predictors of survival. Tumor histology, length of initial remission, initial therapy with two v three drugs, and site of relapse each were independently predictive of postrelapse survival. The 3-year postrelapse survival for all 367 patients was 30% +/- 3%; however, subgroups classified by these prognostic factors were identified that had 3-year postrelapse survival rates of greater than 40%. These subgroups included patients who had tumors of favorable histology (FH) that recurred (1) only in the lungs, (2) in the abdomen when radiotherapy (RT) was not initially given, or (3) that were originally stage I, (4) that were originally treated with only two drugs, or (5) that recurred 12 months or more after diagnosis. These results were achieved with the use of standard treatments, ie, surgery, RT, and chemotherapy using dactinomycin (AMD), vincristine (VCR), and Adriamycin [( ADR] doxorubicin; Adria Laboratories, Columbus, OH). It is suggested that patients in these groups might be managed with aggressive use of conventional therapies until newer chemotherapeutic agents and drug combinations are shown to be more effective. Patients with adverse prognostic features at relapse have a poor survival expectancy with standard measures. Salvage attempts for these patients are better based on experimental approaches.

Adolescent↗
PubMed1988

Age distribution of Wilms' tumor: report from the National Wilms' Tumor Study.

Median ages at diagnosis were 36.5 and 42.5 mo for 1523 males and 1678 females with unilateral Wilms' tumor registered between October 1969 and December 1985; they were 23.5 mo and 30.5 mo for 100 males and 141 females with bilateral disease. The median age for multicentric, unilateral cases was intermediate between the bilateral and unicentric medians. Patients with hemihypertrophy in addition to their Wilms' tumor had a typical age distribution, whereas those with aniridia or characteristic genitourinary anomalies were substantially younger. Patients with perilobar nephroblastomatosis had a median age of 35.5 mo and those with intralobar nephroblastomatosis, a median age of 18.5 mo. Most of the bilateral disease occurred in the presence of one or both of these precursor lesions. These findings suggest heterogeneity in the pathogenesis of Wilms' tumor, having implications for genetic counselling, and call into question certain aspects of Knudson and Strong's two-stage mutational model for the origin of Wilms' tumor.

Adult↗
PubMed1988

Fracture of polycarbonate brackets--a related photoelastic stress analysis.

In clinical use polycarbonate edgewise bracket designs, patterned on metallic predecessors, have demonstrated slot-wing fracture. A preliminary two-dimensional photoelastic stress investigation is described in which two bracket designs, without angles in the edgewise slot component, are subjected to simulated palatal root torque mechanics.

Dental Stress Analysis↗
PubMed1987

Cloning and sequence analysis of simian transforming growth factor-beta cDNA.

We have isolated a cDNA clone coding for the simian TGF-beta precursor from a cDNA library made from an African green monkey cell line, BSC-40. The deduced amino acid sequence of the mature simian TGF-beta shows 100% homology with that of the human TGF-beta: Strong sequence homology was found between the precursor regions of the human and simian proteins with only five amino acid changes out of 278. The simian (and murine) precursor sequence was found to code for one less amino acid residue than the human. The implications of these results with respect to the isolation of a growth inhibitor from these cells functionally related to the TGF-beta molecule are discussed.

Amino Acid Sequence↗