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William Small

Publications and source records attributed to William Small.

24 records · Page 2Linked to original sources

An external evaluation of a peer-run "unsanctioned" syringe exchange program.

In Vancouver, British Columbia, Canada, difficulty accessing syringes at night has been shown to be strongly associated with human immunodeficiency virus (HIV) risk behavior among the city's injection drug users (IDUs). On September 1, 2001, the Vancouver Area Network of Drug Users (VANDU) initiated an unsanctioned all-night needle-exchange program on a street corner in the heart of the neighborhood where many of the city's IDUs are concentrated. An external evaluation of the population reached by the VANDU exchange was performed through the Vancouver Injection Drug User's Study, a prospective cohort study of IDUs begun in 1996. Persons accessing syringes through the exchange were compared to those active injectors who acquired their syringes from other sources, including the city's fixed site exchange, which closes at 8:00 PM. Overall, 587 active IDUs were seen during the period September 2001 to June 2002; of these individuals, 165 (28.1%) reported using the VANDU exchange. In multivariate analyses, participants who used the VANDU table were more likely to frequently inject cocaine (adjusted odds ratio [AOR]=1.56; 95% confidence interval [CI]=1.00-2.44), inject in public (AOR=2.71; 95% CI=1.62-4.53), and require help injecting (OR=2.13; 95% CI=1.33-3.42). Interestingly, use of the table was also independently associated with safer syringe disposal (AOR=2.69; 95% CI=1.38-5.21). Results indicate that the unsanctioned exchange appears to have reached those IDUs at highest risk of HIV infection. Although the cross-sectional nature of the study design warrants caution, we also found that use of the nighttime exchange was strongly associated with higher rates of safe syringe disposal. The data suggest that drug user organizations can play a major role in reducing harm among their peers by reaching the highest risk drug users with harm reduction services. The findings also suggest that other forms of syringe-exchange programs should consider the benefits of offering fixed site nighttime service.

Adult↗

Cytostatic properties of some angiotensin I converting enzyme inhibitors and of angiotensin II type I receptor antagonists.

Angiotensin converting enzyme (ACE) inhibitors and angiotensin II (AII) type 1 receptor antagonists have strong cytostatic properties on in vitro cultures of many normal and neoplastic cells. They are effective, in particular, in reducing the growth of human lung fibroblasts, renal canine epithelial cells, bovine adrenal endothelial cells, simian T lymphocytes, and of neoplastic cell lines derived from human neuroblastomas, a ductal pancreatic carcinoma of the Syrian hamsters, human salivary glands adenocarcinomas, and two lines of human breast adenocarcinomas. ACE inhibitors are also effective in protecting lungs, kidneys and bladders from the development of nephropathy, pneumopathy, cystitis, and eventually fibrosis in different models of organ-induced damage such as exposure to radiation, chronic hypoxia, administration of the alkaloid monocrotaline or bladder ligation. ACE inhibitors and AII type 1 receptor antagonists are also effective in reducing excessive vascular neoformation in a model of injury to the cornea of rats and rabbits, and in controlling the excessive angiogenesis observed in the Solt-Farber model of experimentally induced hepatoma, in methylcholantrene or radiation-induced fibrosarcomas, in radiation-induced squamous cell carcinomas and in the MA-16 viral-induced mammary carcinoma of the mouse. Captopril was, in addition, effective in controlling tumor growth in a case of Kaposi's sarcoma in humans. The inhibition of AII synthesis and/or its blockade by AII receptors is likely to be an important mechanism for this cytostatic action. The mitogenic effect of AII is well established and a reduction of AII synthesis may well explain cell and neoplasm delayed growth. Moreover, AII regulates and enhances the activity of several growth factors including transforming growth factor B (TGFB) and smooth muscle actin (SMA); and many of these factors are reduced in tissues of animals treated with ACE inhibitors and AII type 1 receptor antagonists. These processes seem to be particularly relevant in the control of fibroblast growth and in the control of the ensuing fibrosis. The ACE inhibitors containing a sulphydril (SH) or thiol radical in their moiety (Captopril and CL242817) seemed to be more effective in controlling fibrosis and the growth of some neoplastic cells than those ACE inhibitors without this thiol radical in their structure, even if the second group of these drugs show in vitro a stronger inhibitory effect on converting enzyme activity. Pharmacologically it is known that ACE inhibitors containing a thiol radical also have antioxidant properties and they are efficient in controlling metalloproteinase action. However, although these additional properties are pharmacologically relevant, the blockade of AII synthesis plays an essential role in the cytostatic activity of these two categories of drugs. These observations underline that in addition to the beneficial effect of these drugs on the cardiovascular system, new potential applications are opening for their wider deployment.

Angiotensin Receptor Antagonists↗

Potential for use of amifostine in cervical cancer.

Cisplatin-based combined chemoradiotherapy is now the standard of treatment for locally advanced cervical cancer. Although combined-modality treatment has improved survival, it has also increased the already high frequency of toxicity observed with traditional radiotherapy alone. Cervical cancer patients with para-aortic metastasis may be at particularly high risk of toxicity with combined-modality treatment. The few clinical trial data available on the use of amifostine in cervical cancer or pelvic cancer patients suggest benefit in reducing treatment toxicity. The potential role of amifostine in combination with currently used cisplatin-based chemoradiotherapy regimens is being assessed in a Radiation Therapy Oncology Group phase I/II study in cervical cancer patients with positive para-aortic or high common iliac lymph nodes.

Amifostine↗

The potential role of amifostine in the treatment of carcinoma of the uterine cervix: a review.

Carcinoma of the uterine cervix affects approximately 13,000 women annually in the United States. Radiotherapy is a commonly applied therapy, either as definitive treatment or combined with surgery. Although highly effective, radiotherapy can be associated with significant complications. Amifostine has been shown to be an effective radioprotector in head and neck malignancies. Preliminary evidence suggests a role in cervical cancer.

Amifostine↗

Pathophysiology and management of radiation-induced xerostomia.

Radiotherapeutic treatment of head and neck cancer patients often causes long-term dysfunction involving their salivary function, swallowing capabilities, and taste. Salivary gland dysfunction from radiation therapy is often the most unpleasant side effect of treatment. This article will review current knowledge concerning the anatomy and function of glands involved with salivation, measurement of salivary gland function, surgical and pharmacologic prevention and treatment of xerostomia, and methods to administer radiation while causing the least amount of damage to salivary glands.

Acupuncture Therapy↗