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T A Smith

Publications and source records attributed to T A Smith.

At least 19 recordsLinked to original sources

[Prevalence, genetic diversity and multiplicity of Plasmodium falciparum infection in school children in central Cote d'Ivoire].

A study was carried out in the village of Taabo, located in the vicinity of a large man-made lake in central Côte d'Ivoire. The objectives were (i) to determine the level of prevalence, genetic diversity and multiplicity of Plasmodiumfakiparum infection in schoolchildren and (ii) to compare the diagnostic performance of light microscopy and polymerase chain reaction (PCR). A total of 424 schoolchildren ranging in age from 5 to 15 years underwent diagnostic testing using both light microscopy of blood smears and PCR. Multiplicity of P. falciparum infection was investigated in 196 children (46.2%). The prevalence of malaria was 54.7% based on light microscopy and 83.9% based on PCR. Genotyping based on polymorphism in the length of the restriction fragment of the gene encoding the merozoite surface protein-2 (msp2) showed that 86.5% of cases involved multiple infection with a geometric mean of 3.87 genotypes per positive child. There was a strong positive correlation between multipcity of infection and parasite density in the 56-year old age group. A total of 50 genotypes including six observed for the first time were identified and classified into families with similar-sized sequence groups: 26 x FC27 (52%) and 24 x 3D7 (48%). In comparison with PCR, the sensitivity and specificity of light microscopy for diagnosis of P. falciparum was 81.3% and 88.2% respectively. Data are discussed in the light of similar studies carried out in sub-Saharan Africa and elsewhere. These findings can serve as a basis for monitoring the longterm effect of major water resource management projects on the prevalence, genetic diversity and multiplicity of P. falciparum infection.

Adolescent↗

Code of practice for food handler activities.

BACKGROUND: The food industry regulates various aspects of food handler activities, according to legislation and customer expectations. The purpose of this paper is to provide a code of practice which delineates a set of working standards for food handler hygiene, handwashing, use of protective equipment, wearing of jewellery and body piercing. METHODS: The code was developed by a working group of occupational physicians with expertise in both food manufacturing and retail, using a risk assessment approach. Views were also obtained from other occupational physicians working within the food industry and the relevant regulatory bodies. The final version of the code (available in full as Supplementary data in Occupational Medicine Online) therefore represents a broad consensus of opinion. CONCLUSION: The code of practice represents a set of minimum standards for food handler suitability and activities, based on a practical assessment of risk, for application in food businesses. It aims to provide useful working advice to food businesses of all sizes.

Body Piercing↗

The Child Dental Control Assessment (CDCA) in youth: reliability, validity and cross-cultural differences.

AIM: The Child Dental Control Assessment (CDCA) measures children's preferred control strategies in the dental situation. Three studies are reported, assessing aspects of this instrument in youths from the USA, Japan and Australia. In particular, measurements were made as to the reliability and validity of this instrument in this age group in the three cultures, as well as comparing some results across cultures. STUDY DESIGN: These studies used a questionnaire design. METHODS: Questionnaires (including the CDCA and other measures) were given to youths aged 11-15 in the three cultures. In one culture, youths received the questionnaire twice, to compute test-retest reliability. RESULTS: The measure's reliability and validity were similar to those of other measures. The CDCA behaves similarly to the Revised Iowa Dental Control Index (R-IDCI). Youths in all three cultures showed similar responses, although the Japanese were less likely to endorse items. STATISTICS: Internal reliability of the scale ranged from 0.74 to 0.85. Test- retest reliability was 0.74. Participants in the High Desire/Low Predicted classification on the R-IDCI scored higher on the CDCA (t (73) = 2.9, p < .01). In the Japanese and Australian samples the correlation between CDCA and dental fear was 0.29-0.33 (p < .001). The Australian and USA samples scored significantly higher than the Japanese sample (overall F(2,1544) = 383.98, p < .001, followed by Tukey's HSD, p < .001). CONCLUSIONS: These results provide evidence for the reliability and validity of the CDCA in youth. It appears to measure the discrepancy between Desired and Predicted Control identified in the Revised Iowa Dental Control Index (R-IDCI). Responses of the youth in all three cultures were similar, indicating common dental control preferences for individuals of this age. However, consistent with cultural values, Japanese youth were less likely to endorse the control strategies. These results underline the need to develop culturally-specific, as well as situationally-specific control measures.

Adolescent↗

Preventing baker's asthma: an alternative strategy.

BACKGROUND: Although baker's asthma has attracted considerable research interest over the last 30 years, success in its prevention has been slow to achieve. This paper describes the results of an alternative preventive strategy, based on an observation that the excess of sensitization in bread bakers is largely due to IgE-mediated allergy to fungal amylase, contained in bread improvers. The practical application of the strategy has been to limit bread improver exposures to <1 mg/m3 [8 h time-weighted average (TWA)], whilst exposures to all other ingredients, including flour, have been limited to <10 mg/m3 (8 h TWA). METHOD: The paper describes the findings of in-house respiratory health surveillance and dust sampling programmes, from a UK food company whose primary interests are milling and baking, over the period following the introduction of the strategy to target the reduction in bread improver exposure. RESULTS: Over the 10 year period of surveillance, the incidence of symptomatic sensitization in the bread baking sector (2240 per million employees per annum) was greater than for the other flour-using groups (330 per million employees per annum), despite broadly similar total inhalable dust exposures. There was an overall reduction in the incidence of new cases of symptomatic sensitization, from 2085 per million employees per year in the first 5 years of the surveillance programme, to 405 per million employees per year in the subsequent 5 years. CONCLUSION: The strategy of targeting bread improver exposure is an effective approach for the prevention of new cases of symptomatic sensitization in bread bakeries.

Amylases↗

Incidence of occupational skin conditions in a food manufacturing company: results of a health surveillance programme.

BACKGROUND: The food industry has been associated with a high risk of work-related skin problems. Aim To examine the incidence of work-related skin conditions and the likely causative agents in a single large food company. METHOD: Analysis of a health surveillance programme, conducted over a 7 year period, in a food company with 21 000 employees working in diverse manufacturing processes. RESULTS: The mean incidence of skin conditions, taking all of the different food manufacturing operations together, was 1310 per million employees per annum. The mean incidence was greatest in the manufacturing sector whose operations involved chilled or frozen product (3180 per million employees per annum). Most of the cases reported (184/192 = 96%) were due to primary irritant dermatitis. The two commonest suspected causes of the dermatitis were contact with ingredients and hand washing. Taken together, these factors accounted for 58% of all cases. Although the wearing of gloves is often considered necessary to prevent dermatitis from exposure to ingredients and to lessen the need for hand washing, this factor itself was responsible for 9% of all cases. CONCLUSION: Analysis of a company health surveillance scheme showed the average incidence of work-related skin problems to be lower than previously reported in the food industry.

Dermatitis, Contact↗

Head and neck injuries in fatal motorcycle collisions as determined by detailed autopsy.

Detailed layer-by-layer autopsy of the head and neck was performed on a prospective series of 73 fatally injured motorcyclists in order to identify occult injuries, particularly soft tissue neck injuries such as hemorrhage of vertebral and carotid arteries. The fatal cases were gathered as part of a larger study of 1,082 on-scene in-depth motorcycle crash investigations in Thailand. Detailed neck dissection was done on nearly all fatal cases. Injuries were coded using the 1990 revision of the Abbreviated Injury Scale (AIS 90) and an Injury Severity Score (ISS) was determined for each case. Additional AIS codes are proposed for neck injuries that were often identified during the detailed autopsy procedures, but which are not listed explicitly among existing AIS codes. Helmet use was determined based on analysis of injury patterns and helmet damage with consideration also given to witness statements. Both helmeted and unhelmeted motorcyclists showed a high frequency of occult neck injuries such as hemorrhages in the carotid sheath or surrounding the vertebral arteries, phrenic nerve, or brachial plexus. These soft tissue neck injuries sometimes accompanied more obvious injuries to cervical vertebrae or spinal cord, but about one-third of riders had no obvious injury to suggest the presence of occult neck injury. Twenty-eight motorcyclists had been wearing a helmet at the start of the collision sequence, but only nine helmets remained in place through the entire collision event. Helmeted riders showed more severe somatic (below-the-neck) injuries than unhelmeted riders, suggesting helmeted riders are less likely to die in low-threat accidents with somatic injuries below AIS-3. The most significant finding of this study was the identification of serious internal neck injuries despite the absence of external physical evidence of trauma to the neck. Virtually all riders with significant head injuries showed some of these soft tissue neck injuries. Approximately one-third of the critically injured riders who survived at least a few hours before death showed serious occult soft tissue neck injuries.

Abbreviated Injury Scale↗

Head and neck injuries in fatal motorcycle collisions as determined by detailed autopsy.

Detailed layer-by-layer autopsy of the head and neck was performed on a series of seventy-three fatally injured motorcyclists in order to identify occult soft tissue injuries such as subluxation of the cervical spine or hemorrhage of vertebral or internal carotid arteries. The fatal cases were gathered as part of a larger study of 1082 on-scene in-depth motorcycle crash investigations in Thailand. Injuries were coded using the 1990 Abbreviated Injury Scale (AIS 90) and an Injury Severity Score (ISS) was determined for each case. Twenty-eight motorcyclists had been wearing a helmet at the start of the collision sequence, but only nine helmets remained in place through the entire collision event. Both helmeted and unhelmeted motorcyclists showed a high frequency of neck injuries such as hemorrhages in the carotid sheath compressing the vagus nerve, hemorrhages surrounding the phrenic nerves or the brachial plexus, or hemorrhages surrounding the vertebral arteries. The most significant finding of this study was the identification of serious internal neck injuries even when there was no external physical evidence of trauma to the neck. Virtually all riders with significant head injuries showed some of these soft tissue neck injuries. This may be important for trauma physicians, who are presented with critically injured motorcyclists with complex multiple trauma, which may include occult soft tissue neck injuries.

Abbreviated Injury Scale↗

Child mortality and malaria transmission intensity in Africa.

The desirability of controlling malaria transmission in the areas of highest endemicity of Plasmodium falciparum has long been debated. Most recently, it has been claimed that rates of malaria morbidity are no higher in areas of very high transmission in Africa than they are in places with lower inoculation rates. We now review the literature on the relationship of morbidity and mortality to malaria transmission intensity, and have linked published child mortality and malaria transmission rates to examine how age-specific mortality actually varies with the inoculation rate of P. falciparum.

Africa↗

Immunohistochemical analysis of anaplastic lymphoma kinase expression in deep soft tissue calcifying fibrous pseudotumor: evidence of a late sclerosing stage of inflammatory myofibroblastic tumor?

Calcifying fibrous pseudotumor (CFT) is a rare benign soft tissue lesion composed of dense hyalinized fibrous tissue containing bland spindle-shaped cells admixed with a lymphoplasmacytic infiltrate and foci of dystrophic and often psammomatous calcifications. It has been suggested that CFT represents a late sclerosing stage of inflammatory myofibroblastic tumor (IMT). Recently, clonal cytogenetic abnormalities involving the anaplastic lymphoma kinase (ALK) gene on chromosome 2p have been identified in IMT, particularly those arising in deep soft tissue sites. We evaluated seven cases of deep soft tissue CFT diagnosed at the Cleveland Clinic Foundation and the University of Florida with available paraffin-embedded blocks using a monoclonal antibody to ALK (Dako, Carpenteria, CA) and a modified avidin-biotin complex method. The cohort included six women and one man with a median age at diagnosis of 43 years (range, 26 to 67 years). Sites of CFT included mesentery (3), peritoneum (1), omentum (1), serosa of small bowel (1), and anterior mediastinum (1). Immunohistochemically, only one case showed focal staining for ALK. The remaining six cases were negative, with appropriate positive and negative control staining. In conclusion, unlike IMT, CFT in deep soft tissue locations rarely expresses ALK by immunohistochemistry, suggesting that CFT is a different clinicopathologic entity than IMT, as opposed to representing a "burned out" IMT. Ann Diagn Pathol 5:10-14, 2001.

Adult↗

Type A gamma-aminobutyric acid (GABAA) receptor subunits and benzodiazepine binding: significance to clinical syndromes and their treatment.

Gamma (gamma)-aminobutyric acid (GABA) acting via GABAA receptors is the brain's major inhibitory neurotransmitter system and exerts a crucial role in regulating brain excitability. A number of drugs interact with binding sites on GABAA receptors, and these include benzodiazepines, anticonvulsants, anaesthetics and neurosteroids (e.g. the progesterone metabolite pregnalone). GABAA receptors comprise five subunits (19 are known currently), and are classified into three major groups (alpha, beta and gamma) and several minor ones. The subunit make-up of a receptor, particularly its alpha-subunit content, determines its pharmacological characteristics. Thus, receptors that include an alpha1 subunit have a benzodiazepine (BZ) type I (BZ[I]) pharmacology and bind zolpidem and CL218,872 with high affinity, whilst receptors with alpha2, alpha3 or alpha5 subunits have a BZ type II (BZ[II]) pharmacology and bind these drugs with low affinity. In contrast to receptors that contain alpha4 and alpha6 subunits, which are diazepam-insensitive, both BZ(I) and -(II) bind diazepam and other benzodiazepines. The ligand selectivity of receptor subunits assists in their characterisation. Using immunochemical and ligand-binding techniques, the subunit composition of GABAA receptors has been shown to exhibit a degree of brain regional specificity. GABAA receptors are of great clinical significance in several disorders, including epilepsy, anxiety and alcoholism. In addition to treating epilepsy with drugs that target GABAA and BZ binding sites, epileptic lesions can be localised presurgically using radiolabelled BZ ligands. BZs are used commonly to treat anxiety, and studies suggest that BZ antagonists and inverse agonists (which induce the opposite effect to agonists at receptors) may be useful in alcohol rehabilitation.

Alcoholism↗

University of Kentucky community-based field experience: program description.

Community-based field experiences (CBFE) provide students with exemplary experiential learning opportunities. The purposes of this paper are to describe the University of Kentucky College of Dentistry (UKCD) CBFE and report the results of a two-year, self-report survey that assessed the primary course goal, students' perceptions of change in knowledge and skills related to nineteen areas of patient care (n = 90, 100% return rate), and their overall rating of the program. Knowledge and skill data were analyzed using the non-parametric binomial test for comparing proportions. A significant (.05 level) majority of students reported increases in knowledge in all areas to which they were exposed. Descriptive frequencies summarizing the results of the total CBFE experience indicate that the majority of students felt it was a positive experience. The CBFE continues to be a meaningful element in the UKCD curriculum as it provides students with a relevant, authentic educational experience.

Community Dentistry↗

[Prognosis in Guillain-Barre syndrome assessed by clinical and neurophysiological features].

The Guillain-Barrés' syndrome (GBS) is an acute inflammatory demyelinating polyradiculoneuropathy with a relatively low incidence and a relatively good prognosis. Patients with the axonal form of GBS often have a worse prognosis. Eleven patients who were unable to walk were analyzed clinically and with nerve conduction studies in the acute illness and at a follow-up 9-54 months. The first nerve conduction study characterized seven patients with demyelinating GBS and four with axonal GBS. At follow-up nine patients had no or minor symptoms and two had moderate symptoms. There was accordance between clinical and neurophysiological findings. Patients with axonal GBS had a worse prognosis. The incidence on the island of Fyn was 1.4 per 100,000.

Adolescent↗

Use of abdominal ultrasonography in the diagnosis of primary hyperaldosteronism in a cat.

A 13-year-old castrated male cat was examined because of a 2-week history of weakness, cervical ventroflexion, and dysphagia. Clinicopathologic abnormalities included hypokalemia and high serum creatine kinase activity. Abdominal ultrasonography revealed a 15-mm spherical mass in the area of the left adrenal gland. Plasma aldosterone concentration was high, and plasma renin activity was low. Findings were diagnostic of primary hyperaldosteronism. The cat responded well to intravenous and oral potassium supplementation while in the hospital. The owner declined surgery; therefore, repeated follow-up abdominal ultrasonography was recommended. The cat did well clinically with medical management alone until day 334, when it was lost to follow-up.

Adrenal Gland Neoplasms↗

Deoxyglucose uptake by a head and neck squamous carcinoma: influence of changes in proliferative fraction.

PURPOSE: Positron emission tomography, using the glucose analogue fluorodeoxy-D-glucose (FDG), is proving to be useful in the early response detection of head and neck tumors. Presently mechanisms underlying changes in FDG uptake after therapy are poorly understood. Response of tumors to therapy is often accompanied by a decrease in tumor cell proliferation. The purpose of this study was to assess whether or not changes in the uptake of deoxyglucose (DG) may reflect differences in proliferative fraction independent of other metabolic changes induced by using therapeutic agents. METHODS AND MATERIALS: HN5 head and neck tumor cells were grown to different cell densities producing populations of cells with different proliferative indices without the need for exogenous agents to manipulate cell-cycle kinetics. (3)H-DG uptake, S-phase fraction (Spf), and lactate production were determined in each population of cells. RESULTS: Large differences in Spf between populations of cells were associated with differences in DG incorporation. Lactate production was also found to correlate strongly with DG uptake. CONCLUSION: Therapy-induced changes in FDG uptake by tumors may be partly due to changes in proliferation.

Biomarkers↗