Promotion of mouthguards among amateur football players in Victoria

Abstract: Wearing mouthguards while playing contact sports reduces the prevalence and severity of orofacial injuries. We report on a 1991–92 promotion of mouthguard use among amateur football players in Melbourne. Four questionnaires were completed by players (1991 season: middle: n =638, 49 per cent response; late: n =770, 51 per cent; 1992: early: n =505, 26 per cent; late: n =698, 54 per cent), in four age groups (16–19, 20–23, 24–29, 30–44 years), about perceived mouthguard value and usage, injury experience, and awareness of a promotional message. Over the two seasons, mouthguard ownership and consistent wear increased and dental injuries decreased. Ownership of mouthguards increased among: 20–23 year olds and 30–44 year olds (13 and 16 per cent); managers, tradespersons, salespersons, labourers and the unemployed (14–19 per cent); residents of northern and western regions (12 and 13 per cent); those with 6 to 10 years of education (29 per cent); players in old boys' networks (13 per cent); and those with English as a first language (8 per cent). Consistent wear was high at matches (89 per cent) but low at training (13 per cent), owing to perceived lack of physical contact. Of dental injuries reported by 25–31 per cent, fractures predominated over luxations and avulsions. Fractures and avulsions were more common at matches than training; luxations predominated at training. When a mouthguard was not worn, the likelihood of a fractured or avulsed tooth was at least twice that when a mouthguard was worn. Some injuries occurred despite the wearing of mouthguards. The promotional message appeared effective in increasing mouthguard use; newspapers and football journals provided effective message locations for players, and ground signs and the electronic scoreboard for spectators.     

Hereditary Cerebral Hemorrhage with Amyloidosis-Dutch Type (HCHWA-D): I - A Review of Clinical, Radiologic and Genetic Aspects

Hereditary cerebral hemorrhage with amyloidosis - Dutch type (HCHWA-D) is an autosomal dominant disease caused by deposition of β-amyloid in the leptomeningeal arteries and cortical arterioles, in addition to preamyloid deposits and amyloid plaques in the brain parenchyma.
The disease is due to a point mutation at codon 693 of the amyloid precursor protein (βPP) gene at chromosome 21. Since this point mutation is diagnostic for HCHWA-D, presymptomatic testing is feasible and offered, together with genetic counselling and psychological support, to subjects at risk. HCHWA-D is clinically characterized by recurrent strokes, in addition to dementia, which can occur after the first stroke but also preceding it. Radiological studies revealed focal lesions (hemorrhages, hemorrhagic and non-hemorrhagic infarctions) and diffuse white matter damage. Diffuse white matter hyperintensities on MRI are an early symptom of HCHWA-D since they have been found on MRI scans of subjects who had not suffered a stroke.
The presence of the diagnostic point mutation makes HCHWA-D a useful model to study the effects of cerebral amyloid angiopathy in vivo. The characteristic pathological abnormalities and its implications for Alzheimer's disease will be discussed in Part II of this article     

Suprascapular nerve entrapment at the spinoglenoid notch in a professional baseball pitcher

Suprascapular nerve injuries at the spinoglenoid notch are uncommon. The true incidence of this lesion is unknown; however, it appears to be more common in athletes who participate in sports involving overhead activities. When a patient is being evaluated for posterior shoulder pain and infraspinatus muscle weakness, electrodiagnostic studies are an essential part of the evaluation. Electromyography will identify an injury to the suprascapular nerve as well as assist in localizing the site of injury. In addition, imaging studies are also indicated to help exclude other diagnoses that can mimic a suprascapular nerve injury. The initial management should consist of cessation of the aggravating activity along with an organized shoulder rehabilitation program. If the patient fails to improve with 6 months to 1 year of nonoperative management, surgical exploration of the suprascapular nerve should be considered. Release of the spinoglenoid ligament with resultant suprascapular nerve decompression may result in relief of pain and a return of normal shoulder function.     

Dibenzo[a,l]pyrene-induced DNA adduction, tumorigenicity, and Ki-ras oncogene mutations in strain A/J mouse lung

Dibenzo[a,l]pyrene (DB[a,l]P), an environmental polycyclic aromatic hydrocarbon, is the most potent carcinogen ever tested in mouse skin and rat mammary gland. In this study, DB[a,l]P was examined for DNA adduction, tumorigenicity, and induction of Ki-ras oncogene mutations in tumor DNA in strain A/J mouse lung. Groups of mice received a single i.p. injection of 0.3, 1.5, 3.0, or 6.0 mg/kg DB[a,l]P in tricaprylin. Following treatment, DNA adducts were measured at times between 1 and 28 days, while tumors were counted at 250 days and analyzed for the occurrence of point mutations in codons 12 and 61 of the Ki-ras oncogene. DB[a,l]P in strain A/J mouse lung induced six major and four minor DNA adducts. Maximal levels of adduction occurred between 5 and 10 days after injection followed by a gradual decrease. DB[a,l]P-DNA adducts in lung tissue were derived from both anti- and syn-11,12- dihydroxy-13,14-epoxy- 11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE) and both deoxyadenosine (dAdo) and deoxyguanosine (dGuo) residues in DNA as revealed by cochromatography. The major adduct was identified as a product of the reaction of an anti-DB[a,l]PDE with dAdo in DNA. DB[a,l]P induced significant numbers of lung adenomas in a dose- dependent manner, with the highest dose (6.0 mg/kg) yielding 16.1 adenomas/mouse. In tricaprylin-treated control animals, there were 0.67 adenomas/mouse. Based on the administered dose, DB[a,l]P was more active than other environmental carcinogens including benzo[a]pyrene. As a function of time-integrated DNA adduct levels, DB[a,l]P induced lung adenomas with about the same potency as other PAHs, suggesting that the adducts formed by DB[a,l]P are similar in carcinogenic potency to other PAHs in the strain A/J mouse lung model. Analysis of the Ki- ras mutation spectrum in DB[a,l]P-induced lung tumors revealed the predominant mutations to be G-->T transversions in the first base of codon 12, A-->G transitions in the second base of codon 12, and A-->T transversions in the second or third base of codon 61, concordant with the DNA adduct profile.      

Early stage nasopharyngeal carcinoma: radiotherapy dose and time factors in tumor control

OBJECTIVE: To evaluate radiotherapy dose and length of treatment in the control of early stage nasopharyngeal carcinoma (NPC) treated with a combination of external radiotherapy and brachytherapy, MATERIALS & METHODS: We reviewed the records of 133 patients with early stage nasopharyngeal carcinoma (stage I or II, AJC/UICC staging system) who received definitive radiotherapy in Chang Gung Memorial Hospital from 1979 to 1991. The median follow-up time was 7.1 years with a minimum of 2 years. All patients were treated with megavoltage external radiotherapy to the nasopharynx area (63-72 Gy) followed by high dose rate intracavitary brachytherapy (5-16.5 Gy in one to three fractions, spaced 1-2 weeks apart). The median total dose and time of irradiation was 75 Gy (69.8-81.4 Gy) and 11.6 weeks (7.8-20 weeks) respectively. Survival analysis was used to examine the effect of several variables on prognosis. RESULTS: The 5-year rates were 86.4% for local control, 84.7% for disease free survival, 88.5% for actuarial survival and 84.2% for overall survival. The treatment group (combination of time and dose of irradiation) was the most important prognostic factor according to Cox's proportional hazard model. Patients receiving radiation at a total dose of < or = 75 Gy completed in < 12 weeks showed the best prognosis. CONCLUSION: Treatment time and total treatment dose are both important factors in treating early stage NPC. Decreasing the total radiation time to < 12 weeks and not exceeding a radiation dose of 75 Gy gave the best results.      

Myocardial mechanics and energetics in experimental iron-deficiency anemia.

The effect of iron-deficiency anemia on myocardial mechanics and energetics was studied in 10 anesthetized bealge puppies. Nine littermates served as controls. Left ventricular/body weight ratio was increased 14.2% (P less than 0.05) and cardiac index 36.5% (P less than 0.02) in the anemic puppies. Heart rate, mean systolic pressure, myocardial lactate extraction coefficient, and lactic dehydrogenase isozymes were similar in both groups. Contractile state measured in vivo (pressure-velocity curves) and in isolated muscles (isotonic force-velocity curves) was virtually identical in the littermate groups. Despite markedly increased coronary blood flow in the anemia animals, oxygen consumption per unit weight of myocardium was the same in both groups. Contractile element efficiency averaged 18.3% in 10 adult mongrel dogs studied in a similar fashion and was 27.1% and 39.8% in the normal puppies and anemic puppies, respectively. The oxygen cost of internal or force-generating work was similar among the three groups of dogs. It is concluded that the volume load produced by iron-deficiency anemia was associated with a normal contractile state, normal unit myocardial oxygen consumption, no evidence of chronic anaerobiosis, and a high contractile element efficiency, perhaps as a consequence of increased diastolic fiber stretch.     

The Urban Built Environment and Associations with Women’s Psychosocial Health

The determinants that underlie a healthy or unhealthy pregnancy are complex and not well understood. We assess the relationship between the built environment and maternal psychosocial status using directly observed residential neighborhood characteristics (housing damage, property disorder, tenure status, vacancy, security measures, violent crime, and nuisances) and a wide range of psychosocial attributes (interpersonal support evaluation list, self-efficacy, John Henryism active coping, negative partner support, Perceived Stress Scale, perceived racism, Center for Epidemiologic Studies—Depression) on a pregnant cohort of women living in the urban core of Durham, NC, USA. We found some associations between built environment characteristic and psychosocial health varied by exposure categorization approach, while others (residence in environments with more rental property is associated with higher reported active coping and negative partner support) were consistent across exposure categorizations. This study outlines specific neighborhood characteristics that are modifiable risk markers and therefore important targets for increased research and public health intervention.     

Perceived Access and Actual Intake of Healthy Diets Among Households in Vulnerable Salvadoran Communities

ObjectiveThis study aimed to examine the dietary intake of Salvadoran households according to perceived access to healthy meals (PAHD), and to identify household characteristics associated with diet quality and PAHD.MethodsSecondary data analysis with a sample of 139 Salvadoran households from resource-poor communities in El Salvador. Chi-square tests and ANOVA were used to assess differences in dietary intake across households classified according to PAHD.ResultsHigh-PAHD households had higher women's education, household food security levels, overall diet quality, and variety, and higher intakes of animal products, fats, cholesterol, vitamin C, and sodium (P < .05). Diet quality was not associated with the household characteristics studied.Conclusions and ImplicationsOverall diet quality was associated with higher levels of PAHD, but some differences in intakes were not as expected, such as higher intakes in foods and nutrients associated with low-quality diets, among high PAHD households.