Warranty and preventative maintenance

For products sold with warranty, preventive maintenance actions by manufacturers and/or buyers have an impact on the total costs for both parties. This paper develops a framework to study preventive maintenance actions when items are sold under warranty and reviews the models that have appeared in the literature. It then develops a new model and carries out its analysis.

Gastrointestinal worm infections. The prevalence and treatment in Australia

BACKGROUND:Intestinal worm (helminth) infections occur in a large proportion of the world's population, often constituting public health problems, and are occasionally encountered by practitioners in urban Australia. Prevalence levels in some remote Australian Aboriginal communities compare with those in developing countries. OBJECTIVE: To provide general practitioners with a brief outline of the most common human intestinal helminthiases, their usual clinical presentations and how they are diagnosed and managed. DISCUSSION: The pinworm, Enteroblus vermicularis, occurs in all populations, and is the most common species of nematode encountered in suburbia. Eradication is impossible, but its numbers can be kept low in those children who seem predisposed to heavy, symptomatic infections. The other nematodes are prevalent in some remote Australian Aboriginal communities, and are encountered occasionally in travellers from overseas. These infections are often asymptomatic, they cannot spread directly to other people and so do not pose any public health threat to the general community under suburban living conditions. The tapeworms are encountered even less frequently, except for Hymenolepis, the dwarf tapeworm, which is prevalent in some Aboriginal communities.

Association of clinical, radiological and synovial immunopathological responses to anti-rheumatic treatment in rheumatoid arthritis

Objectives. To compare immunohistochemical scoring with clinical scoring and radiology for the assessment of rheumatoid arthritis (RA) disease activity, synovial tissue (ST) biopsied arthroscopically was assessed from 18 patients before and after commencement of disease-modifying anti-rheumatic drug (DMARD) therapy. Methods. Lymphocytes, macrophages, differentiated dendritic cells (DC), vascularity, tumour necrosis factor (TNF)alpha and interleukin-1 beta levels were scored. Clinical status was scored using the American College of Rheumatology (ACR) core set and serial radiographs were scored using the Larsen and Sharp methods. Histopathological evidence of activity included infiltration by lymphocytes, DC, macrophages. tissue vascularity, and expression of lining and sublining TNF alpha. These indices co-varied across the set of ST biopsies and were combined as a synovial activity score for each biopsy. Results. The change in synovial activity with treatment correlated with the ACR clinical response and with decreased radiological progression by the Larsen score, The ACR response to DMARD therapy. the change in synovial activity score and the slowing of radiological progression were each greatest in patients with high initial synovial vascularity. Conclusions. The data demonstrate an association between clinical, radiological and synovial immunopathological responses to anti-rheumatic treatment in RA. High ST vascularity may predict favourable clinical and radiological responses to treatment.

Operative treatment of ankle fractures: A minimum ten-year follow-up

The long-term outcome of 25 patients with bimalleolar fractures of the ankle was assessed ten to fourteen years following their fractures using the Phillips scoring system. All patients had undergone open reduction and anatomical internal fixation (as described in their operative notes in the medical records). 52 % of patients had a good or excellent overall outcome while 24% had a poor overall outcome. This study has the longest follow-up period (10 to 14 years) to date on the outcomes of internal fixation of bimalleolar ankle fractures and demonstrates a higher percentage of poorer outcomes than has been previously described. This trend appears to be predictable as other studies with shorter term follow-up have already established a trend of increasing radiological evidence of post-traumatic arthritis with successively longer-term outcome reports.

Review of treatment of pterygium in Queensland: 10 years after a primary survey

Purpose: To assess the practices in pterygium removal as a follow-up study to a similar project 10 years ago, in order to compare the current trends with those noted a decade ago. Methods: A survey was sent to all practising ophthalmologists in Queensland (100). Results: Eighty-seven of the 100 ophthalmologists undertook pterygium surgery with no change in indications for removal, grading or anaesthesia compared to 10 years ago. Nearly half of the ophthalmologists varied their surgical technique from eight commonly used methods according to the individual patient. More than half the respondents used a swinging conjunctival flap and 29% used simple excision leaving the area bare for primary pterygia, although nearly one-quarter of the ophthalmologists added adjunctive therapies such as beta irradiation or mitomycin. For recurrent pterygia, one-third of ophthalmologists preferred adjunctive therapies, and 57% used an autoconjunctival transplant. Conclusion: There has been no consistent trend in surgical removal of pterygia with a significant number of primary pterygia still removed using bare scleral closure.

Supervisory control of wastewater treatment plants by combining principal component analysis and fuzzy c-means clustering

In this paper a methodology for integrated multivariate monitoring and control of biological wastewater treatment plants during extreme events is presented. To monitor the process, on-line dynamic principal component analysis (PCA) is performed on the process data to extract the principal components that represent the underlying mechanisms of the process. Fuzzy c-means (FCM) clustering is used to classify the operational state. Performing clustering on scores from PCA solves computational problems as well as increases robustness due to noise attenuation. The class-membership information from FCM is used to derive adequate control set points for the local control loops. The methodology is illustrated by a simulation study of a biological wastewater treatment plant, on which disturbances of various types are imposed. The results show that the methodology can be used to determine and co-ordinate control actions in order to shift the control objective and improve the effluent quality.

Dietary and supplement treatment of iron deficiency results in improvements in general health and fatigue in Australian women of childbearing age

Objective: To examine the effects of iron deficiency and its treatment by iron supplementation or a high iron diet on fatigue and general health measures in women of childbearing age. Design: Randomised controlled trial to compare supplement and dietary treatment of iron deficiency. Subjects: 44 iron deficient (serum ferritin < 15 mug/L or serum ferritin 15-20 mug/L, plus two of the following: serum iron < 10 mu mol/L, total iron binding capacity > 68 mu mol/L or transferrin saturation < 15%) and 22 iron replete (hemoglobin greater than or equal to 120 g/L and serum ferritin > 20 mug/L) women 18 to 50 years of age were matched for age and parity. Interventions: Iron deficient women were randomly allocated to either iron supplementation or a high iron diet for 12 weeks. Measures of Outcome: Iron deficient and iron replete participants had iron studies performed and completed the Piper Fatigue Scale (PFS) and the SF-36 general health and well-being questionnaire at baseline (TO), following the 12 week intervention (TI) and again after a six-month non-intervention phase (T2). The SF-36 includes measures of physical (PCS) and mental (MCS) health and vitality (VT). Results: MCS and VT scores were lower and PFS scores were higher for iron deficient women (diet and supplement groups) than iron replete women at baseline. Both intervention groups showed similar improvements in MCS, VT and PFS scores during the intervention phase, but mean increases in serum ferritin were greater in the supplement than the diet group. PCS scores were not related to iron status. Conclusions: Treatment of iron deficiency with either supplementation or a high iron diet results in improved mental health and decreased fatigue among women of childbearing age.

Dietary treatment of iron deficiency in women of childbearing age

Background: The Australian Iron Status Advisory Panel advocates dietary intervention as the first treatment option for mild iron deficiency [serum ferritin (SF) = 10-15 mug/L]. However, there appear to be no studies on the efficacy of dietary treatment for iron deficiency. Objective: We compared the effects of iron supplementation and of a high-iron diet on serum ferritin (SF) and hemoglobin in iron-deficient women of childbearing age. Design: Forty-four iron-deficient women (SF < 15 mug/L or SF = 15-20 mug/L plus serum iron < 10 mu mol/L and total-iron-binding capacity > 68 mu mol/L) and 22 iron-replete women (hemoglobin greater than or equal to 120 g/L and SF > 20 mug/L) matched for age and parity categories were enrolled and completed 7-d weighed food records at baseline. The iron-deficient women were randomly allocated to receive iron supplementation (105 mg/d; supplement group) or a high-iron diet (recommended intake of absorbable iron: 2.25 mg/d; diet group) for 12 wk. Hematologic and dietary assessments were repeated at the end of the intervention and again after a 6-mo follow-up. Results: Mean SF in the supplement group increased from 9.0 +/- 3.9 mug/L at baseline to 24.8 +/- 10.0 mug/L after the intervention and remained stable during follow-up (24.2 +/- 9.8 mug/L whereas the diet group had smaller increases during the intervention (8.9 +/- 3.1 to 11.0 +/- 5.9 mug/L) but continued to improve during follow-up (to 15.2 +/- 9.5 mug/L). Mean hemoglobin tended to improve in both intervention groups, but the change was only significant in the supplement group. Conclusions: In iron-deficient women of childbearing age, a high-iron diet produced smaller increases in SF than did iron supplementation but resulted in continued improvements in iron status during a 6-mo follow-up.

Early Australian experience with infliximab, a chimeric antibody against tumour necrosis factor-alpha, in the treatment of Crohn's disease: is its efficacy augmented by steroid-sparing immunosuppressive therapy?

Background: Tumour necrosis factor-alpha (TNF-alpha) plays an important role in the pathology of Crohn's disease. Infliximab, a chimeric antibody against TNF-alpha, has been shown in controlled clinical trials to be effective in two-thirds of patients with refractory or fistulating Crohn's disease. The factors that determine a clinical response in some patients but not others are unknown. Aims: To document the early Australian experience with infliximab treatment for Crohn's disease and to identify factors that may determine a beneficial clinical response. Methods: Gastroenterologists known to have used infliximab for Crohn's disease according to a compassionate use protocol were asked to complete a spreadsheet that included demographic information, Crohn's disease site, severity, other medical or surgical treatments and a global clinical assessment of Crohn's disease outcome, judged by participating physicians as complete and sustained (remission for the duration of the study), complete but unsustained (remission at 4 weeks but not for the whole study) or partial clinical improvement (sustained or unsustained). Results: Fifty-seven patients were able to be evaluated, with a median follow-up time of 16.4 (4-70) weeks, including 23 patients with fistulae. There were 21 adverse events, including four serious events. Fifty-one patients (89%) had a positive clinical response for a median duration (range) of 11 (2-70) weeks. Thirty patients (52%) had a remission at 4 weeks, 10 of whom had remission for longer than 12 weeks. Forty-two per cent of fistulae closed. Sustained remission (P = 0.065), remission at 4 weeks (P = 0.033) and a positive clinical response of any sort (P = 0.004) were more likely in patients on immunosuppressive therapy, despite there being more smelters in this group. Conclusion: This review of the first Australian experience with infliximab corroborates the reported speed and efficacy of this treatment for Crohn's disease. The excellent response appears enhanced by the concomitant use of conventional steroid-sparing immunosuppressive therapy.

Outcomes of cephalosporin treatment for serious infection due to apparently susceptible organisms producing extended-spectrum b-Lactamases: Implications for the clinical microbiology laboratory

Although extended-spectrum beta-lactamases (ESBLs) hydrolyze cephalosporin antibiotics, some ESBL-producing organisms are not resistant to all cephalosporins when tested in vitro. Some authors have suggested that screening klebsiellae or Escherichia coli for ESBL production is not clinically necessary, and when most recently surveyed the majority of American clinical microbiology laboratories did not make efforts to detect ESBLs, We performed a prospective, multinational study of Klebsiella pneumoniae bacteremia and identified 10 patients who were treated for ESBL-producing K. pneumoniae bacteremia with cephalosporins and whose infecting organisms were not resistant in vitro to the utilized cephalosporin. In addition, we reviewed 26 similar cases of severe infections which had previously been reported. Of these 36 patients, 4 had to be excluded from analysis. Of the remaining 32 patients, 100% (4 of 4) patients experienced clinical failure when MICs of the cephalosporin used for treatment were in the intermediate range and 54% (15 of 28) experienced failure when MICs of the cephalosporin used for treatment were in the susceptible range, Thus, it is clinically important to detect ESBL production by klebsiellae or E, coli even when cephalosporin MICs are in the susceptible range (less than or equal to 8 mug/ml) and to report ESBL-producing organisms as resistant to aztreonam and all cephalosporins (with the exception of cephamycins).

Treatment of lupus nephritis: art or science? [Editorial]

No Abstract

Effects of high-dose etidronate treatment on microdamage accumulation and biomechanical properties in beagle bone before occurrence of spontaneous fractures

We recently demonstrated that suppressed bone remodeling allows microdamage to accumulate and causes reductions in some mechanical properties. However, in our previous study, I year treatment with high-dose etidronate (EHDP) did not increase microdamage accumulation in most skeletal sites of dogs in spite of complete remodeling suppression and the occurrence of spontaneous fractures of ribs and/or thoracic spinous processes. This study evaluates the effects of EHDP on microdamage accumulation and biomechanical properties before fractures occur. Thirty-six female beagles, 1-2 years old, were treated daily for 7 months with subcutaneous injections of saline vehicle (CNT) or EHDP at 0.5 (E-low) or 5 mg/kg per day (E-high). After killing, bone mineral measurement, histomorphometry, microdamage analysis, and biomechanical testing were performed. EHDP treatment suppressed intracortical and trabecular remodeling by 60%-75% at the lower dose, and by 100% at the higher dose. Osteoid accumulation caused by a mineralization deficit occurred only in the E-high group, and this led to a reduction of mineralized bone mass. Microdamage accumulation increased significantly by two- to fivefold in the rib, lumbar vertebra, ilium, and thoracic spinous process in E-low, and by twofold in the lumbar vertebra and ilium in E-high. However, no significant increase in damage accumulation was observed in ribs or thoracic spinous processes in E-high where fractures occur following 12 months of treatment. Mechanical properties of lumbar vertebrae and thoracic spinous processes were reduced significantly in both E-low and E-high. These findings suggest that suppression of bone remodeling by EHDP allows microdamage accumulation, but that osteoid accumulation reduces production of microdamage. (Bone 29:271-278; 2001) (C) 2001 by Elsevier Science Inc. All rights reserved.