[Epidemiological aspects of traumas with intraocular foreign bodies]. / Aspectos epidemiológicos de traumatismos con cuerpos extraños intraoculares.

OBJECTIVES: To evaluate the epidemiological aspects, diagnosis, therapeutical procedures, and factors of poor prognosis in patients with intraocular foreign bodies. METHODS: A descriptive and retrospective study carried out at The Hospital Comarcal del Bierzo (Leon), between June 1996 and May 2001, with an average follow-up period of 2 years. It comprises 86 patients affected by serious ocular traumatism who required hospitalization and surgery, 25 of whom had an intraocular foreign body (30%). RESULTS: The average age was 46, and 88% were males. Accidents at work account for 72% of cases, domestic accidents for 24%, and leisure activities for 4%. The nature of the material causing the accident was metallic in 80% of cases, and non-metallic materials in 20%. In 60% of patients, the final visual acuity was less than 0.5. CONCLUSIONS: Labour accidents cause ocular traumas with foreign body entrance. In most cases foreign bodies have a metallic composition. Diagnosis was made through direct exploration, roentgenography, CT scan and ultrasonography. We proceeded to carry out urgent admission, antitetanus and antibiotic prophylaxis as well as reconstruction of ocular globe. Main bad-prognosis factors were a diminished previous visual acuity, the presence of afferent pupillary defect, organic composition of foreign body and the occurrence of late complications.

Parathyroid detection in secondary hyperparathyroidism with 123I/99mTc-sestamibi subtraction single photon emission computed tomography.

123I/99mTc-sestamibi subtraction single photon emission computed tomography (SPECT) has been proposed to detect hyperplastic parathyroid tissue, but the clinical usefulness of this technique in secondary hyperparathyroidism is uncertain. The purpose of this study was to evaluate preoperative parathyroid localization using 123I/99mTc-sestamibi subtraction SPECT in patients with renal failure and secondary hyperparathyroidism. Nineteen patients with chronic renal failure and secondary hyperparathyroidism underwent 123I/99mTc-sestamibi subtraction SPECT imaging preoperatively. None of these patients had undergone previous neck surgery. The location, weight, and histopathological results of all identified parathyroid glands were recorded. Surgery was considered successful in all patients, with resection of a total of 74 hyperplastic parathyroid glands. 123I/99mTc-sestamibi subtraction SPECT correctly identified 57 of these parathyroid glands (77% sensitivity). The mean weight among the true positive glands (n = 57) was 1031 mg (range, 45-7900 mg), and that among the false negative glands (n = 17) was 465 mg (range, 20-1800 mg). This difference between the mean weights was statistically significant (P = 0.018). There was a positive correlation between parathyroid weight and detectability with 123I/99mTc-sestamibi subtraction SPECT (Spearman correlation = 0.28; P = 0.0167). 123I/99mTc-sestamibi subtraction SPECT is able to correctly localize hyperplastic parathyroid glands in patients with renal failure and secondary hyperparathyroidism, but there is a fairly weak relationship between preoperative detection rate and anatomical parathyroid gland size.

Sestamibi/iodine subtraction single photon emission computed tomography in reoperative secondary hyperparathyroidism.

BACKGROUND: Sestamibi/iodine subtraction single photon emission computed tomography (SPECT) has been used successfully for the preoperative localization of adenomatous and hyperplastic parathyroid tissue in primary hyperparathyroidism, but the clinical usefulness of this technique in secondary hyperparathyroidism remains uncertain. The purpose of this study was to evaluate parathyroid localization that uses sestamibi/iodine subtraction SPECT in patients with secondary hyperparathyroidism before reoperative parathyroid surgery. METHODS: Fourteen consecutive patients with chronic renal failure and secondary hyperparathyroidism who had previously undergone total parathyroidectomy combined with parathyroid autotransplantation in a sternocleidomastoid muscle were studied. Before reoperation, each patient received 400 microCi of sodium iodide I 123 orally and 20 to 25 mCi of technetium Tc 99m ((99m)Tc)-sestamibi intravenously, followed by sestamibi/iodine subtraction SPECT of the neck and chest. At surgery, the location, weight, and histopathologic results of all identified parathyroid tissue were recorded. RESULTS: At surgery, 1 hyperplastic parathyroid gland was resected from each of 13 patients; including 1 undescended gland, 6 parathyroid autotransplants, and 5 mediastinal glands. The mean weight of the resected parathyroid glands was 1707 mg (range, 85-5300 mg). Sestamibi/iodine subtraction SPECT correctly identified and localized all 13 parathyroid glands (100% sensitivity) and was negative in the 1 patient whose surgery was unsuccessful. CONCLUSIONS: The (99m)Tc-sestamibi/(123)I subtraction SPECT is able to correctly localize hyperplastic parathyroid tissue in patients with secondary hyperparathyroidism who have previously undergone parathyroid surgery and is a clinically useful study before reoperation.

Prevalence of anti-HCV in two Tanzanian villages.

The presence of anti-HCV antibodies was investigated in sera from a total of 123 inhabitants of two Tanzanian villages. In one of the villages, 72.2% of the sera and in the other village, 82.6% of the sera were found to be anti-HCV positive. These values are dramatically higher than other reported prevalences, whereby cross-reactivity between HCV and Flaviviruses as well as possible transmission by arthropod vectors cannot be ruled out.

Epidemiological study of parasitic infections in Somali nomads.

In Somali nomads the incidence of intestinal helminths is very low compared with that observed in Somalian closed institutions and practically no Entamoeba infection occurs. Schistosoma haematobium eggs are observed in urine of 50% of adults nomads. Immunological tests reveal that the relative prevalences of leishmaniasis (the lowest), malaria, and toxoplasmosis (the highest) in nomads are similar to those shown by the same techniques in settled communities.

Posttraumatic cerebral hemispheric swelling. Analysis of 55 cases studied with computerized tomography.

The authors have analyzed the clinical course and intracranial pressure (ICP) changes in 55 severely head-injured patients presenting with bulk enlargement of one cerebral hemisphere within a few hours after trauma. These patients represent 10.5% of a series of 520 patients with severe head injury studied with computerized tomography (CT). Cerebral hemispheric swelling has the highest mortality rate and the shortest survival period after trauma in all series of severe head injury. In this series, it was associated with an ipsilateral subdural hematoma of variable size in 47 patients (85%) or with a large epidural hematoma in five patients (9%); in three patients (5.4%) it occurred as an isolated lesion. Evacuation of an associated extracerebral hematoma, which was performed within 4 hours after injury in only 20% of cases, scarcely changed the patients' preoperative neurological status. The high incidence of arterial hypotension and/or hypoxemia at admission (47% of cases) and the severity of the clinical presentation (82% of patients scored 5 points or less on the Glasgow Coma Scale, 74% had unilateral or bilateral mydriasis, and 80% had an initial ICP above normal) correlated with a very poor final outcome (87% mortality). Only one of the 11 patients with normal initial ICP continued to have normal pressure throughout the course. High-dose thiopental failed to control severe intracranial hypertension in 24 patients (51%) who had a fulminant, malignant course. A transient decrease in ICP elevation was achieved in 15 patients (31.4%) and definitive control in eight patients (17%), among whom were the seven survivors in this series. In the authors' experience, once ICP is controlled, barbiturate administration should not be discontinued until a control CT scan shows complete disappearance of the mass effect.

Use of a stopped-flow pneumatic mixing module to analyze dinitrophenol pesticides. Simultaneous determination of dinoseb and dinobuton.

A kinetic study of the degradation of dinobuton in an alkaline medium has been undertaken by using a stopped-flow pneumatic system. A semiautomatic method for determining dinobuton is proposed for the first time. A detection limit of 0.40 microg mL(-)(1) was calculated. Simultaneous determination of dinobuton and dinoseb can be made by combination of equilibrium and kinetic measurements. The proposed method has been applied to analyze binary mixtures of dinobuton and dinoseb samples with the amount of both components simulating the composition of one undegraded and several degraded dinobuton samples. Also, the procedure has been tested in the analysis of a commercial formulation of dinobuton and the results validated with high-performance liquid chromatography (HPLC).

Kinetic fluorimetric determination of the antineoplastic methotrexate (MTX) in human serum.

A kinetic study of the oxidation of methotrexate (MTX) in acidic medium and in the presence of potassium permanganate has been made on the basis of the fluorescence-time curves. A kinetic method for the determination of MTX was developed with a range of application between 0.22 and 3.30 microM. The proposed kinetic method permits us to determine MTX in human serum and to avoid the natural fluorescence of the serum. A detection limit of 0.18 microM was calculated in the presence of ascorbic acid as activator. Only 100 s per sample is necessary for the analysis. The interference of pteridin derivatives and the rescue agent folinic acid (leucovorin) was tested.

Tetrahydrobiopterin synthesis is induced by LPS in vascular smooth muscle and is rate-limiting for nitric oxide production.

GTPCH1 mRNA and BH4 synthesis is increased by LPS in vascular smooth muscle. Our data suggest that induction of GTPCH1 and NOS represent two arms of a common pathway required for immunostimulant-evoked NO synthesis. This conclusion is consistent with the view that the major function of immunostimulant-evoked BH4 is to support NOS. Moreover, GTPCH1 and other enzymes of the de novo BH4 synthetic pathway may prove to be important targets for therapy of clinical conditions arising from NO overproduction. As we begin to reveal the molecular events governing the induction and expression of GTPCH1 and NOS, additional therapeutic approaches for treating NO overproduction are certain to be revealed.

The characteristics of epilepsy in a largely untreated population in rural Ecuador.

A house-to-house survey of epileptic seizures covering a population of 72,121 persons was carried out in a rural area of northern Ecuador. A cascade system of diagnosis was used to identify all cases of epileptic seizures in this population. 1029 cases were found, of whom 881 were considered to be definite cases and 148 were possible cases. Of the 1029 cases, 56% had active epilepsy. The lifetime prevalence rate was found to lie between 12.2 and 19.5/1000 and the prevalence of active cases between 6.7 and 8.0/1000. An annual incidence rate of between 122/100,000 and 190/100,000 was estimated. Seizure type was classified without EEG data and almost half of the cases had partial seizures. In 27% of cases an aetiology was proposed on clinical grounds. This is one of few reported studies of a population that has been largely unexposed to antiepileptic drugs, providing an opportunity to study the natural history of the untreated condition. It has been suggested that treatment in newly developing epilepsy will prevent its development to a chronic condition. Only 37% of the 1029 cases had ever received antiepileptic drugs, and only 12% of the cases were taking them at the time of the survey. Despite this, a high rate of inactivity was observed, with 44% of all cases free of seizures. Nearly two thirds of the inactive cases identified had never received treatment with antiepileptic drugs. In a subgroup of untreated cases with an active condition, treatment with antiepileptic drugs was initiated and was highly effective even in cases with a long previous history. Thus the findings from this study suggest that the development of epilepsy resistant to therapy is not always associated with a long duration of untreated epilepsy.

Cerebral hemisphere swelling in severe head injury patients.

The clinical course and the intracranial pressure (ICP) changes in 66 severe head injury patients presenting bulk enlargement of one cerebral hemisphere within a few hours of trauma have been analyzed. These patients represent 11% of a series of 589 severe head injury cases studied with computerized tomography (CT). Cerebral hemisphere swelling, which was associated with an ipsilateral subdural haematoma of variable extent in 58 patients (88%), or a large epidural haematoma in 5 patients (7%), and occurred as an isolated lesion in 3 patients (4%), carried the highest incidence of uncontrollable intracranial hypertension, the highest mortality rate and the shortest survival period after trauma in the authors' severe head injury series. The high incidence of arterial hypotension and/or hypoxaemia at admission (48% of cases), and the severity of clinical presentation (82%) of patients scored 5 patients or less in the Glasgow Coma Scale, 77% had uni- or bilateral mydriasis and 82% initial ICP above normal limits) correlated with the very poor final outcome (85% mortality). Only one of the 12 patients with normal initial ICP continued to have low pressure throughout the course. High dose thiopental failed to control severe intracranial hypertension in 29 patients (44%) who had a fulminant, malignant course. A transient decrease in ICP elevation was achieved in 17 patients (26%) and a definitive control in 12 patients (18%), among them the 10 survivors in this series. In the authors experience once ICP is controlled, and unless haemodynamic instability compells action to the contrary, barbiturate should not be discontinued until a control CT scan shows complete disappearance of the mass effect.

Evaluation of the sensitivity of microfilter paper assays in an anthropological study: results of samples from Cameroon and Tanzania.

Microfilter absorbed whole blood samples from 223 Tanzanian babies and 189 adults from Cameroon have been examined. Blood specimens are difficult to obtain from African suburban and rural areas, and lack of storage and transportation facilities can prevent the collection of samples. We evaluated some microassays employing whole blood collected on filter paper. This method is a well established technique in neonatal screening for endocrinometabolic diseases. We also developed microassays for whole dried blood spots to type AB0 blood groups and HIV disease using commercial reagents. Phenotype and gene frequencies for AB0 and hemoglobin systems as well as our results concerning the typings of thyroxine (T4), thyroid stimulating hormone (TSH), human immunodeficiency virus (HIV) and hepatitis B virus (HBV) are reported.