Severe hypercalcemia after a single high dose of vitamin D in a patient with sarcoidosis.

LETTER TO THE EDITOR

AVALIAÇÃO ECOTOXICOLÓGICA DO RESÍDUO DE MINERAÇÃO DE CARVÃO

RESUMO O descarte de grandes quantidades de resíduos de mineração de carvão modifica quimicamente o solo e isso pode alterar a estrutura e atividade da fauna edáfica. Objetivou-se estudar os efeitos ecotoxicológicos das deposições de resíduo piritoso (carvão mais a pirita) em dois solos, coletados em Santa Catarina, Argissolo Vermelho-Amarelo e Nitossolo Háplico, nas doses de 0; 2,5; 5; 10 e 20 % desse resíduo. Os testes realizados foram sobrevivência e reprodução de Enchytraeus crypticus e de germinação comAvena sativa e Lotus corniculatus. O valor de pH, independentemente do tipo do solo, diminuiu à medida que aumentou a dose de resíduo piritoso. O resíduo piritoso na menor dose resultou em efeitos negativos ao E. crypticus, como redução na taxa sobrevivência de adultos e nenhuma reprodução. Nos testes de sobrevivência e reprodução de enquitreídeos, o valor de LC50 (concentração estimada que pode causar efeitos negativos na sobrevivência e germinação em 50 % de um grupo de organismos) ficou abaixo 4 % e EC50 (efeitos negativos na reprodução) <2,5 % para os dois solos, respectivamente. A exposição de A. sativa aos dois solos não expressou efeito tóxico para L. corniculatus, no Nitossolo. Porém, no Argissolo, a contaminação causou efeitos na menor dose para L. corniculatus. No teste de germinação de sementes, somente L. corniculatus apresentou sensibilidade no Argissolo Vermelho-Amarelo (LC50<4 %). A elevada sensibilidade dos organismos do solo avaliado à aplicação do resíduo piritoso influenciou-os negativamente, tanto em um curto período de tempo quanto em longo prazo.

Iniciativas públicas de redução da violência escolar no Brasil

Este artigo apresenta algumas ações do Poder Público que buscaram reduzir a violência em meio escolar. Tomando como exemplo as cidades de São Paulo, Porto Alegre e Belo Horizonte, examina algumas das modalidades de práticas que nascem a partir da década de 80, início do processo de democratização política do Brasil. Oscilando entre medidas de caráter educativo e iniciativas relacionadas à área de segurança, as ações ainda demandam continuidade e maior capacidade de impacto nas escolas públicas dessas cidades. No entanto, já é possível, a partir dessas experiências, traçar a trajetória emergente das políticas públicas destinadas à diminuição da violência nos estabelecimentos de ensino na sociedade brasileira.

Treating the individual hypertensive patient: considerations on dose, sequential monotherapy and drug combinations.

For the general practitioner to be able to prescribe optimal therapy to his individual hypertensive patients, he needs accurate information on the therapeutic agents he is going to administer and practical treatment strategies. The information on drugs and drug combinations has to be applicable to the treatment of individual patients and not just patient study groups. A basic requirement is knowledge of the dose-response relationship for each compound in order to choose the optimal therapeutic dose. Contrary to general assumption, this key information is difficult to obtain and often not available to the physician for many years after marketing of a drug. As a consequence, excessive doses are often used. Furthermore, the physician needs comparative data on the various antihypertensive drugs that are applicable to the treatment of individual patients. In order to minimize potential side effects due to unnecessary combinations of compounds, the strategy of sequential monotherapy is proposed, with the goal of treating as many patients as possible with monotherapy at optimal doses. More drug trials of a crossover design and more individualized analyses of the results are badly needed to provide the physician with information that he can use in his daily practice. In this time of continuous intensive development of new antihypertensive agents, much could be gained in enhanced efficacy and reduced incidence of side effects by taking a closer look at the drugs already available and using them more appropriately in individual patients.

Dose-dependent effect of atrial natriuretic peptide on blood pressure, heart rate, and skin blood flow of normal volunteers.

Synthetic atrial natriuretic peptide, containing 26 amino acids in the rat sequence, L-364, 343 (Ileu-ANP), was infused intravenously at increasing rates (1-40 micrograms/min) into four normal volunteers. Mean intraarterial blood pressure decreased and heart rate increased in cumulative-dose-dependent fashion. Skin blood flow as measured with a laser Doppler device rose already with a cumulative dose of 55 micrograms Ileu-ANP and further rises were directly related to dose. The only side effects observed were those accompanying symptomatic hypotension at higher doses. These findings provide strong evidence that Ileu-ANP acts as a vasodilator in normal volunteers.

Screening of illegal intracorporeal containers ("body packing"): is abdominal radiography sufficiently accurate? A comparative study with low-dose CT.

PURPOSE: To evaluate the diagnostic performance of abdominal radiography in the detection of illegal intracorporeal containers (hereafter, packets), with low-dose computed tomography (CT) as the reference standard. MATERIALS AND METHODS: This study was approved by the institutional ethical review board, with written informed consent. From July 2007 to July 2010, 330 people (296 men, 34 women; mean age, 32 years [range, 18-55 years]) suspected of having ingested drug packets underwent supine abdominal radiography and low-dose CT. The presence or absence of packets at abdominal radiography was reported, with low-dose CT as the reference standard. The density and number of packets (≤ 12 or >12) at low-dose CT were recorded and analyzed to determine whether those variables influence interpretation of results at abdominal radiography. RESULTS: Packets were detected at low-dose CT in 53 (16%) suspects. Sensitivity of abdominal radiography for depiction of packets was 0.77 (41 of 53), and specificity was 0.96 (267 of 277). The packets appeared isoattenuated to the bowel contents at low-dose CT in 16 (30%) of the 53 suspects with positive results. Nineteen (36%) of the 53 suspects with positive low-dose CT results had fewer than 12 packets. Packets that were isoattenuated at low-dose CT and a low number of packets (≤12) were both significantly associated with false-negative results at abdominal radiography (P = .004 and P = .016, respectively). CONCLUSION: Abdominal radiography is mainly limited by low sensitivity when compared with low-dose CT in the screening of people suspected of carrying drug packets. Low-dose CT is an effective imaging alternative to abdominal radiography.

Adverse effects of high dose carnitine supplementation of total parenteral nutrition on protein and fat oxidation in the critically ill.

The aim of the present study was to investigate the effects of continuous and acute L-carnitine supplementation of total parenteral nutrition (TPN) on protein and fat oxidation in severe catabolism. A critically ill and severely malnourished male patient received TPN (non protein energy = 41 kcal/kg/day, provided equally as fat and glucose) over 38 days, without L-carnitine for 23 days and with carnitine supplements (15 mg/kg/day) for the following 15 days. Subsequently, he was given carnitine-free enteral nutrition for 60 more days. A four-hour infusion of 100 mg L-carnitine was given on day 11 of each TPN period. Indirect calorimetry was carried out after 11 days of either carnitine-free or supplemented TPN and at the initiation of enteral nutrition. Additional measurements were performed 4 hours and 24 hours after the acute infusions of carnitine. The rate of protein oxidation and the respiratory quotient were found to be higher, and the rate of fat oxidation to be lower, with carnitine-supplemented TPN, than with either carnitine-free TPN or enteral nutrition. Acute infusion of carnitine resulted in an increased rate of protein oxidation and a reduced rate of fat oxidation on both TPN-regimens. These unfavourable effects on protein metabolism may be due to an impairment of fat oxidation by excess amounts of carnitine.

Low-dose theophylline enhances the anti-inflammatory effects of steroids during exacerbations of chronic obstructive pulmonary disease

ABSTRACT Background: Chronic obstructive pulmonary disease (COPD) is characterised by an abnormal inflammatory response mainly to cigarette smoke that flares up during exacerbations of the disease (ECOPD). Reduced activity of histone deacetylases (HDAC) contributes to enhanced inflammation in stable COPD. It was hypothesised that HDAC activity is further reduced during ECOPD and that theophylline, an HDAC activator, potentiates the antiinflammatory effect of steroids in these patients. A study was performed to investigate HDAC activity during ECOPD and the effects of theophylline on the anti-inflammatory effects of steroids in a randomised single-blind controlled study. Methods: 35 patients hospitalised with ECOPD and treated according to international guidelines (including systemic steroids) were randomised to receive or not to receive low-dose oral theophylline (100 mg twice daily). Before treatment and 3 months after discharge, HDAC and nuclear factor-kB (NF-kB) activity in sputum macrophages, the concentration of nitric oxide in exhaled air (eNO) and total antioxidant status (TAS), tumour necrosis factor a (TNFa), interleukin (IL)-6 and IL8 levels in sputum supernatants were measured. Results: Patients receiving standard therapy showed decreased NF-kB activity, eNO concentration and sputum levels of TNFa, IL6 and IL8, as well as increased TAS during recovery of ECOPD, but HDAC activity did not change. The addition of low-dose theophylline increased HDAC activity and further reduced IL8 and TNFa concentrations. Conclusions: During ECOPD, low-dose theophylline increases HDAC activity and improves the anti-inflammatory effects of steroids.

CT dose optimization when changing to CT multi-detector row technology

The purpose of this article was to review the strategies to control patient dose in adult and pediatric computed tomography (CT), taking into account the change of technology from single-detector row CT to multi-detector row CT. First the relationships between computed tomography dose index, dose length product, and effective dose in adult and pediatric CT are revised, along with the diagnostic reference level concept. Then the effect of image noise as a function of volume computed tomography dose index, reconstructed slice thickness, and the size of the patient are described. Finally, the potential of tube current modulation CT is discussed.

Exercise dose and insulin sensitivity: relevance for diabetes prevention.

PURPOSE: Exercise improves insulin resistance and is a first line for the prevention and treatment of type 2 diabetes. The extent, however, to which these responses are dose dependent is not known. The purpose of this study was to examine whether exercise dose was associated with improvements in insulin sensitivity after 4 months of exercise training in previously sedentary adults. METHODS: Fifty-five healthy volunteers participated in a 16-wk supervised endurance exercise intervention with a pre/postintervention design. Insulin sensitivity was assessed by euglycemic hyperinsulinemic clamp, peak oxygen uptake by a graded exercise test, and body composition by dual-energy x-ray absorptiometry. The exercise intervention consisted of three to five sessions per week with a minimum of three sessions supervised. A ramped exercise prescription protocol was used to achieve 75% of peak HR for 45 min per session. Exercise dose, expressed as average kilocalories expended per week, was computed as the product of exercise intensity, duration and frequency. RESULTS: Improved insulin sensitivity was significantly related to exercise dose in a graded dose-response relationship. No evidence of threshold or maximal dose-response effect was observed. Age and gender did not influence this dose-response relationship. Exercise intensity was also significantly related to improvements in insulin sensitivity, whereas frequency was not. CONCLUSIONS: This study identifies a graded dose-response relationship between exercise dose and improvements in insulin sensitivity. The implication of this observation is of importance for the adaptation of exercise prescription in clinical situations.