Tumorigenesis of mammary gland by 7,12-dimethylbenz(a)anthracene during pregnancy: relationship with DNA synthesis

The relationship between mammary cell proliferation during pregnancy and susceptibility to 7,12-dimethylbenz(a)anthracene (DMBA) was examined. DMBA was administered intravenously to Sprague-Dawley rats on the 5th, 10th or 15th day of pregnancy. [3H]thymidine labelling index (LI) of the mammary cells at the time of treatment with the carcinogen was determined and found to be higher in the pregnant rats than in age-matched virgin controls. In spite of the high proliferative index of the mammary cells, significant inhibition of tumorigenesis occurred in the pregnancy rats allowed to complete pregnancy and parturition following treatment with DMBA. However, when pregnancy was terminated by cesarian section shortly after treatment with DMBA, there was a significantly higher tumor incidence as compared to the "full-term" rats. It was observed that the earlier the pregnancy was terminated, the greater was the incidence of mammary tumors. This would indicate that the inhibitory effect of pregnancy is related to changes occurring during the later half of gestation. The differentiation of mammary cells for milk synthesis as pregnancy progresses is postulated to be a major reason for the observed refractoriness of the mammary cells to DMBA at that time.     

Microbially triggered drug delivery to the colon.

Increasing acceptance of protein- and peptide-based drugs necessitates an investigation into the suitability of various sites for their administration. Colon is being investigated for delivery of such molecules. Colon-specific drug delivery is designed to target drug molecules specifically to this area. Development of site-specific delivery systems may exploit a specific property of the target site for drug activation/release. The gastrointestinal tract is inhabited by over 400 bacterial species, each having a specific niche in the tract. Colon, the distal part of the intestine is inhabited by a large variety of gram negative microflora. This flora produces a vast number of enzymes which are being exploited for formulation of colon-specific drug delivery systems. A number of microbially activated systems for colon-specific drug delivery are being evaluated. These include prodrugs and synthetic or natural polymer-based delivery systems. This article aims at reviewing the various microbially activated drug delivery systems for colon-specific drug delivery with specific reference to the microflora of the various segments of the gastrointestinal tract and their role in targeting drug delivery to the colon.     

Scintigraphic findings in peroneal tendonitis: a case report

A case report of radionuclide bone scan findings in a patient with peroneus brevis tendonitis is presented. Peroneal tendonopathy is a common cause of lateral ankle pain. Although magnetic resonance imaging (MRI) findings have been described in the literature, we know of no other detailed report of three-phase bone scan findings, which we believe can provide an alternate means to diagnose this condition. The positive findings consist of a curvilinear band of increased activity that corresponded to the anatomic position of the peroneus brevis tendon and was detected only on the first two phases of the study.     

Sustaining better diabetes care in remote indigenous Australian communities*

Problem: Inhabitants of Torres Strait Islands have the highest prevalence of diabetes in Australia and many preventable complications. In 1999, a one year randomised cluster trial showed improved diabetes care processes and reduced admissions to hospital when local indigenous health workers used registers, recall and reminder systems, and basic diabetes care plans, supported by a specialist outreach service. This study looked at whether those improvements were sustained two years after the end of the trial.

Design: Three year follow up clinical audit of 21 primary healthcare centres, and review of admissions to hospital in the previous 12 months.

Background and Setting: Remote indigenous communities in far north east Australia, population about 9600, including 921 people with diabetes.

Key Measures for Improvement: Number of people on registers, care processes (regular measures of weight, blood pressure, haemoglobin A1c, urinary protein concentration, and concentrations of serum lipids and creatinine), appropriate clinical interventions (drug treatment and vaccinations), and intermediate patient outcome measures (weight, blood pressure, and glycaemic control). Admissions to hospital.

Strategies for Change: Audit and feedback to clinicians and managers; provision of clinical guidelines and a clear management structure; workshops and training.

Effects of Change: The number of people on registers increased from 555 in 1999 to 921 in 2002. Most care processes and clinical interventions improved. The proportion of people with good glycaemic control (haemoglobin A1c 7%) increased from 18% to 25% in line with increased use of insulin (from 7% to 16%). The proportion of those with well controlled hypertension (< 140/90) increased from 40% to 64%. The proportion admitted to hospital with a diabetes related condition fell from 25% to 20%. Mean weight increased from 87 kg to 91 kg.

Lessons Learnt: In remote settings, appropriate management structures and clinical support for people with diabetes can lead to improvements in care processes, control of blood pressure, and preventable complications that result in admission to hospital. Control of weight and glycaemia are more difficult and requires more active community engagement. Priorities now include increasing the availability and affordability of good food, achieving weight loss, and increasing appropriate use of hypoglycaemic agents, including insulin.