Trends in Tuberculosis Reported From the Appalachian Region: United States, 1993-2005

ABSTRACT:  Context: Appalachia has been characterized by its poverty, a factor associated with tuberculosis, yet little is known about the disease in this region. Purpose: To determine whether Appalachian tuberculosis risk factors, trends, and rates differ from the rest of the United States. Methods: Analysis of tuberculosis cases reported to the Centers for Disease Control and Prevention's National Tuberculosis Surveillance System (NTSS) within the 50 states and the District of Columbia from 1993 through 2005. Results: The 2005 rate of tuberculosis in rural Appalachia was 2.1/100,000, compared to 2.7/100,000 in urban Appalachia. Urban non-Appalachia had a 2005 tuberculosis rate of 5.4/100,000. Over the 13-year period, tuberculosis rates fell in Appalachia at an annual rate of 7.8%. In one age group (15- to 24-year-olds) the rates increased at an annual rate of 2.8%. Foreign-born Hispanics were the largest racial/ethnic group in this age group. When private providers gave exclusive care for tuberculosis disease, Appalachians were less likely to complete therapy in a timely manner when compared to non-Appalachians (OR 0.6, 95% CI 0.5-0.7). Conclusions: Tuberculosis rates and trends are similar in urban and rural Appalachia. It is crucial for public health officials in Appalachia to address the escalating TB rate among 15- to 24-year-olds by focusing prevention efforts on the growing numbers of foreign-born cases. Due to the increased risk of treatment failure among Appalachians who do not seek care from the health department, public health authorities must ensure completion of treatment for patients who seek private providers.     

Moderators of the intention-behaviour and perceived behavioural control-behaviour relationships for leisure-time physical activity

Background  

Intention is a key determinant of action. However, there is a gap between intention and behavioural performance that remains to be explained. Therefore, the aim of this study was to identify moderators of the intention-behaviour and perceived behavioural control (PBC)- behaviour relationships for leisure-time physical activity.     

Treatment of periodontal furcation defects Coronally positioned flaps versus dura mater membranes in class II defects

Abstract Mandibular class II furcation defects in 19 subjects were treated using 2 different methods of wound closure. In 16 of the defects, the wound was closed with a coronally positioned surgical flap secured by crown-attached sutures. In 15 of the defects, a collagenous membrane (freeze-dried dura mater) was placed to cover the exposed defect, followed by suturing of the surgical flap at the level of the alveolar crest. After use of a coronally positioned flap, an average of 70% of the defect volume became filled with bone, with complete closure by bone fill for 9 of the 16 treated defects. After use of dura mater membrane, 38% of the defect volume was filled with bone, with complete bony closure for 3 of the 15 treated defects. The results following use of coronally positioned flaps support our previous findings and the potentials of this technique. The results following use of dura mater membranes, together with recently reported risk for spread of virus with dura implants, do not justify the use of dura mater for these regenerative purposes.     

Changes in human sensory axonal excitability induced by an ischaemic insult.

OBJECTIVE: To identify the sensitivity and the patterns of change in sensory excitability that accompany an ischaemic insult. METHODS: Sensory excitability studies were undertaken in 10 subjects (mean age 36), and monitored throughout ischaemia and following its release. Ischaemia was induced using a sphygmomanometer inflated to 200mm/Hg above the elbow. RESULTS: During ischaemia there was reduction in threshold (P<0.001), associated with a significant increase in refractoriness (106+/-6.62%; P<0.001), reduction in superexcitability (30.4+/-0.42%; P<0.001), and 'fanning in' of threshold electrotonus, all indicative of axonal depolarization. Paraesthesiae were minimal during ischaemia, but became severe on release, at which stage numbness was prominent. Late subexcitability in sensory axons was completely abolished by a relatively shorter period of ischaemia than previously observed in motor axons. CONCLUSIONS: The present study has successfully developed a template for changes in sensory axonal excitability parameters that accompany ischaemia, and established their relative sensitivity to an ischaemic change. Further, it is proposed that the inhibition of the Na+/K+ pump, in the setting of increased persistent Na+ currents and abolition of late subexcitability may underlie the development of paraesthesiae during ischaemia. SIGNIFICANCE: Changes in axonal excitability induced by ischaemia may serve as a tool to identify and interpret changes in axonal membrane potential recorded in neuropathic patients.     

A phase II trial for the optimisation of treatment position in the radiation therapy of prostate cancer

BACKGROUND: Patient immobilisation and position are important contributors to the reproducibility and accuracy of radiation therapy. In addition the choice of position can alter the external contour of the treated area and has the potential to alter the spatial relationship between internal organs. The published literature demonstrates variation in the use of the prone and supine position for prostate cancer radiation therapy. Previous investigators using different protocols for patient preparation, imaging and target volume definition have demonstrated changes in the calculated therapeutic ratio comparing the two positions. We did not use rigid immobilisation, laxatives, rectal catheters or bladder voiding and assessed if in the prone position would cause a reduction of the dose to the rectum. We performed a prospective comparison of the two positions in 26 patients to determine if the differences in the spatial relation between the rectum and the planning target volume (PTV) would impact on dose-volume histograms to organs at risk (OAR). We also determined if any such improvement might permit dose escalation. MATERIALS AND METHODS: Twenty-six patients with clinically localized prostate cancer consented to participate in this study. All patients underwent a planning CT scan in both the prone and supine treatment positions. The PTV and OAR were drawn on each set of scans by one of the investigators. The PTV included the prostate and seminal vesicles with a 1cm margin except posteriorly where this margin was reduced to 5mm. The outer circumference of the bladder, rectal wall, small bowel (when present) was drawn along with femoral heads. 3D conformal treatment plans were computed using Helax TMS version 6.1B. A 3-field treatment technique was employed with energy of 10/15 MV. The prescribed dose was 70 Gy and the PTV was encompassed by the 95% isodose and the maximum dose was always less than 107%. Cumulative dose-volume histograms were calculated for the PTV, rectum, bladder, femoral heads and small bowel (when present). These non-uniform histograms for both the prone and supine treatment positions were transformed into uniform ones using the effective volume method [Kutcher J, Burman C. Calculation of probability factors for non-uniform normal tissue irradiation: the effective volume method. Med Phys 1987;14:487]. RESULTS: Twenty-one of the 26 (80%) patients had a lower effective volume of rectum irradiated if the prone instead of the supine treatment position was used. The median value of the effective volume in the supine treatment position was 31.74 Gy while the median value in the prone position was 22.48 Gy. The dose escalation was applied to the patients in the prone treatment position until the effective volume for the rectum was the same as that in the supine position. The range of dose escalation possible for these patients was 0.1-7.9 Gy. These patients could potentially have the dose escalated from the prescribed dose of 70 Gy for the supine position without any increase in side effects. For the five patients where no potential benefit was found when changing treatment position, only two patients displayed a significant (>1 Gy) advantage for the supine treatment position. Twenty-one of the 26 patients also showed an advantage for the prone treatment position in relation to bladder dose. CONCLUSION: The use of the prone position reduced the dose to the unprepared rectum and unvoided bladder in the majority of cases. It should be considered particularly in cases where large posterior seminal vesicles cause significant overlap between the planning target volume and the rectum.