Reference level for patient dose in dental skull lateral teleradiography

The present work describes an experiment to obtain a local reference dose value in lateral skull teleradiography for dental applications. The reference value was based on patient measurements in seven dental X-ray units, using thermoluminescent chips, and measurements on a rubber globe filled with water at another 78 installations. Dosemeters were located initially in the head and neck of a human phantom to select the most suitable locations, and on the cephalostat of the X-ray unit at two appropriate locations, which did not interfere with the patient or with the usual imaging routine. The skin projection of the Porion point was considered the best position. 523 patients were monitored in the seven units; then patient doses and dose values from measurements on rubber balloons were compared to normalize and combine the data. The provisional reference value proposed is 400 microGy.

Study of the antibody response against Mycobacterium tuberculosis antigens in Warao Amerindian children in Venezuela

This study was aimed at investigating alternate methods for serodiagnosis of tuberculosis (TB), which are needed because bacteriologic diagnosis of childhood TB is difficult. A selection of 80 serum and saliva samples were tested from Warao indigenous children under 15 years of age; 34 high TB suspects (28 positive and 6 negative for the tuberculin skin test, TST) and 46 healthy contact children (32 positive and 14 negative for the TST). Several enzyme-linked immunosorbent assay (ELISA) serological tests were developed to test for Mycobacterium tuberculosis-specific antibodies, including serum IgA, IgG, IgE, and secretory IgA (sIgA) in saliva against 3 specific antigens (PPD, HSP60, 38 kDa). Of these, 2 antigens, PPD and 38 kDa, showed significantly higher reactivity. The sensitivity and specificity of these tests for diagnosis remained limited, between 26.5% and 38.2%, and 77.4% and 97%, respectively. Of all the samples studied and combinations realized between all isotypes and antigens combined with 3 isotypes (anti-PPD IgG, IgE, and anti-38kDa sIgA) managed to detect the largest number of patients, showing an improved sensitivity level of 64.7%, although specificity levels dropped to 81.8%. These results were compared with the Omega diagnostics commercial kit results. The commercial kits showed significantly lower reactivity (sensitivity of 20% and 13.33% to Myco G and Complex Plus, respectively) and a specificity of 100%. This study shows that in indigenous populations of Venezuela, where invasive procedures cannot be used to select samples but evaluation with a chest X-ray for radiological studies is available, the combination of 3 specific isotypes may be a useful tool to increase diagnostic accuracy with pulmonary TB in this population, when used together with clinical and epidemiological criteria.

[Acute renal failure in a patient with myelodysplastic syndrome and paroxysmal nocturnal hemoglobinuria phenotype]

Hemoglobin and myoglobin heme pigments and iron have acute and chronic nephrotoxic effects, which are often associated with massive hemolysis and rhabdomyolysis. We report a patient with a myelodysplastic syndrome and paroxysmal nocturnal hemoglobinuria phenotype who developed an acute renal failure after a severe haemolytic crisis. There was not evidence of renal vascular pathology, urinary tract obstruction or prerenal factors. Renal biopsy showed features of acute tubular necrosis, with extended iron deposits in tubule cell cytoplasm and tubulo-interstitial fibrosis and atrophy. The patient was oliguric requiring hemodialisys during three weeks, recovering renal function on the fourth week after admission. This case underlines the nephrotoxic role of heme pigment and iron, and possible pathophysiologic mechanisms involved in acute and chronic toxicity of both agents are reviewed.

The concentrations of arsenic and other toxic elements in Bangladesh's drinking water

For drinking water, the people of Bangladesh used to rely on surface water, which was often contaminated with bacteria causing diarrhea, cholera, typhoid, and other life-threatening diseases. To reduce the incidences of these diseases, millions of tubewells were installed in Bangladesh since independence in 1971. This recent transition from surface water to groundwater has significantly reduced deaths from waterborne pathogens; however, new evidence suggests disease and death from arsenic (As) and other toxic elements in groundwater are affecting large areas of Bangladesh. In this evaluation, the areal and vertical distribution of As and 29 other inorganic chemicals in groundwater were determined throughout Bangladesh. This study of 30 analytes per sample and 112 samples suggests that the most significant health risk from drinking Bangladesh's tubewell water is chronic As poisoning. The As concentration ranged from < 0.0007 to 0.64 mg/L, with 48% of samples above the 0.01 mg/L World Health Organization drinking water guideline. Furthermore, this study reveals unsafe levels of manganese (Mn), lead (Pb), nickel (Ni), and chromium (Cr). Our survey also suggests that groundwater with unsafe levels of As, Mn, Pb, Ni, and Cr may extend beyond Bangladesh's border into the four adjacent and densely populated states in India. In addition to the health risks from individual toxins, possible multimetal synergistic and inhibitory effects are discussed. Antimony was detected in 98% of the samples from this study and magnifies the toxic effects of As. In contrast, Se and Zn were below our detection limits in large parts of Bangladesh and prevent the toxic effects of As.

Subcellular mass determination by 4He+ energy-loss micro-spectrometry

The scanning transmission ion microscope (STIM) has been used to determine the intracellular mass of human cultured cells. A 4He+ microbeam of 2.0 MeV energy was chosen to obtain enhanced ion-energy-loss sensitivity through the micron-thick freeze-dried cells. Local sample mass calculation, based on energy-loss conversion by use of appropriate matrix stopping powers, was performed by use of dedicated software. The method was validated with epoxy resin sections and polymer foil as analogues of biological samples in the range of (intra)cellular thickness, 150 to 3000 nm. STIM analysis resulted in less than 5% error in mass determination. 4He+ energy-loss micro-spectrometry was performed on freeze-dried human ovarian cancer cells, the mean areal mass obtained was 120 microg cm(-2) (200 microg cm(-2) in the nucleus and 250 microg cm(-2) in nucleoli). This method is particularly useful for mass normalization of X-ray fluorescence yields resulting from particle-induced X-ray emission microanalysis (micro-PIXE). When performed successively these two ion-beam micro-analytical methods enable the mapping of true element concentrations within single cells.

Fortified foods. Criteria for vitamin supplementation in Spain

OBJECTIVE

To review and analyse criteria for vitamin supplementation and fortification in Spain.

DESIGN

Systematic review of scientific literature and simulation analysis of food fortification.

METHODS

A simulation analysis using a fortified beverage was performed in a random sample of 2855 children aged 2 to 24 years in Spain.

RESULTS

High-risk groups for vitamin supplementation and fortification in Spain are highlighted, and target vitamins considered have been: folic acid, vitamin A, vitamin E, vitamin D and vitamin B12 (particularly in the elderly). A beverage fortified with vitamins C, A, B1 and B6 may contribute to improving the intake of all of these vitamins with the exception of vitamin A, since the Recommended Nutrient Intake is already covered with current consumption.

CONCLUSIONS

A detailed knowledge of nutritional status helps to ensure the rationale and follow up of nutrient supplementation and fortification.

Renal failure after upper gastrointestinal bleeding in cirrhosis: incidence, clinical course, predictive factors, and short-term prognosis

To assess the incidence, clinical course, predictive factors, and prognosis of renal failure in patients with cirrhosis and gastrointestinal bleeding, 175 consecutive episodes of gastrointestinal bleeding in 161 patients were analyzed. Renal failure occurred in 20 (11%) episodes and was transient in 8 episodes and nontransient in 12. Renal failure was more common in patients with cirrhosis than in a control population of bleeding patients without cirrhosis matched by age and severity of the bleeding episode. Among 39 clinical and laboratory variables obtained at admission or during hospitalization related with the bleeding episode or with liver and renal function, the presence of hypovolemic shock, number of packed red blood cells transfused, Child-Pugh class at admission, and baseline platelet count were independent predictors of renal failure. The development of renal failure and hypovolemic shock was the only independent predictors of in-hospital mortality. Mortality rate among the 20 episodes with renal failure was 55% (11 deaths) as compared with only 3% (5 deaths) in the 155 episodes without renal failure (P <.01). The development of nontransient renal failure entailed a much greater mortality as compared with transient renal failure (10 of 12 [83%] vs. 1 of 8 [12%]; P <.01). In conclusion, renal failure is a common event in patients with cirrhosis and gastrointestinal bleeding, the occurrence of which is mainly related to the severity of bleeding and baseline liver function. Renal failure is a strong predictor of mortality in patients with cirrhosis and gastrointestinal bleeding.

[Lhermitte-Duclos disease associated with tuberous sclerosis. A case report and review of literature]

INTRODUCTION

Lhermitte-Duclos disease is a rare disorder of the cerebellum of unknown origin in which dysplasic thickening of the cerebellar convolutions is seen. It usually occurs in young adults. Currently it is included in the phacomatosis group of disorders.

CLINICAL CASE

A 19 year old woman attended the Emergency Department complaining of progressive orthostatic headache for the previous three months. On examination there were striking facial micronodular lesions suggestive of angiofibromas, a hypo-pigmented macula in the inframammary region and a hyperpigmented 'café-au-lait' macula in the right hypochondrium. On computerized tomography there was tetraventricular hydrocephalia. Cerebral magnetic resonance showed significant descent of the tonsils, hypertensive hydrocephalia and a lesion in the left cerebellum, apparently laminar hyperintensity in DP and T2, with thickening of some folia, not enhanced by intravenous contrast and suggestive of a dysplasic gangliocytoma. Laboratory investigations showed subclinical hypothyroidism. Other investigations were normal. The patient was treated by implanting a ventriculo-peritoneal shunt which has relieved the symptoms to date.

CONCLUSIONS

Lhermitte-Duclos disease is probably not a single anatomo-clinical condition, assuming that it may be a cerebellar hamartoma associated with a phacomatosis with few clinical signs, whether it be Cowden's disease, tuberous sclerosis as in this case or an 'overlapping' syndrome. The magnetic resonance findings are necessary and sufficient for the diagnosis of Lhermitte-Duclos disease.

Painful heel: MR imaging findings

Heel pain is a common and frequently disabling clinical complaint that may be caused by a broad spectrum of osseous or soft-tissue disorders. These disorders are classified on the basis of anatomic origin and predominant location of heel pain to foster a better understanding of this complaint. The disorders include plantar fascial lesions (fasciitis, rupture, fibromatosis, xanthoma), tendinous lesions (tendinitis, tenosynovitis), osseous lesions (fractures, bone bruises, osteomyelitis, tumors), bursal lesions (retrocalcaneal bursitis, retroachilleal bursitis), tarsal tunnel syndrome, and heel plantar fat pad abnormalities. With its superior soft-tissue contrast resolution and multiplanar capability, magnetic resonance (MR) imaging can help determine the cause of heel pain and help assess the extent and severity of the disease in ambiguous or clinically equivocal cases. Careful analysis of MR imaging findings and correlation of these findings with patient history and findings at physical examination can suggest a specific diagnosis in most cases. The majority of patients with heel pain can be successfully treated conservatively, but in cases requiring surgery (eg, plantar fascia rupture in competitive athletes, deeply infiltrating plantar fibromatosis, masses causing tarsal tunnel syndrome), MR imaging is especially useful in planning surgical treatment by showing the exact location and extent of the lesion.

[Effects of tibolone on lipid and glucose metabolism as well as insulin secretion in postmenopausal women]

Tibolone is a synthetic steroid with progestogenic, androgenic and estrogenic properties. In postmenopausal women it has been shown that improves climateric complaints and prevents osteoporosis, without impact on endometrial thickness and uterine fibroids volume. Tibolone administration decreases cholesterol and triglycerides. Although, the effects of hormonal replacement on insulin sensitivity and glucose metabolism has not been well established. The effect of tibolone 2.5 mg/day for 3 months was investigated in 10 healthy postmenopausal women. The results show that tibolone decreases tryglicerides and cholesterol levels along with an increase in fasting insulin levels. The oral glucose tolerance test was unaffected. This study suggests that tibolone reduces markers of cardiovascular disease.