The single recombinant M. tuberculosis protein DPPD provides enhanced performance of skin testing among HIV-infected tuberculosis patients.

Diagnostic testing for M. tuberculosis infection has advanced with QuantiFERON and GeneXpert, but simple cost-effective alternatives for widespread TB screening has remained elusive and purified protein derivative (PPD)-based tuberculin skin testing (TST) remains the most widely used method. PPD-based tests have reduced performance, however, in BCG vaccinees and in individuals with immune deficiencies. We compared the performance of skin testing with the recombinant DPPD protein against that of a standard PPD-based skin test. Our data indicates similar performance of DPPD and PPD (r2 = 0.7689) among HIV-negative, active TB patients, all of whom presented greater than 10 mm induration following administration. In contrast to results demonstrating that PPD induced indurations greater than 5 mm (i.e., the recommended threshold for positive results in this population) in only half (19 of 38) of the HIV positive TB patients, 89.5% (34 of 38) of these participants developed indurations greater than 5 mm when challenged with DPPD. Importantly, none of the patients that were positive following PPD administration were negative following DPPD administration, indicating markedly improved sensitivity of DPPD among HIV-infected individuals. Our data indicate that DPPD has superior performance in skin testing than the current TST standard.

Effect of LED-LCU light irradiance distribution on mechanical properties of resin based materials.

The objective of this study is to analyze the light power distribution along the tip end of the light guide of three LED-LCUs (Light Curing Units) and to evaluate its effect on the mechanical properties of a polymer based dental composite. Firstly, the light power distribution over the whole area of LED-LCU light guide surface was analyzed by three methods: visual projection observation, spectral measurement and optical spectral analysis (OSA). The light power distribution and the total irradiance were different for the three LEDs used, but the wavelength was within the camphorquinone absorption spectrum. The use of a blank sheet was quite on hand to make a qualitative analysis of a beam, and it is costless. Secondly, specimens of a hybrid composite with approximately 8mm diameter and 2mm thickness were produced and polymerized by 20s exposition time to each LED-LCU. Thirdly, the elastic modulus (E) and hardness (HV) were measured throughout the irradiated area by instrumented micro-indentation test (IIT), allowing to correlate localized power and mechanical properties. Both E and HV showed to be very sensitive to local power and wavelength dependent, but they followed the beam power profile. It was also shown that the mechanical properties could be directly correlated to the curing process. Very steep differences in mechanical properties over very short distances may impair the material performance, since residual stresses can easily be built over it.

Additional markers to refine the World Health Organization algorithm for diagnosis of pneumonia.

INTRODUCTION: WHO guidelines for primary care of children with tachypnea indicate that all should receive antibiotics for presumed pneumonia. These guidelines have led to excessive antibiotic use. OBJECTIVE: To examine the value of history of previous respiratory distress, chest indrawing and fever, and response to bronchodilator(BD) to refine these guidelines. DESIGN: Prospective study. SETTING: Urban tertiary care hospital. SUBJECTS: Children, between the ages of 6 and 59 months, presenting with cough and tachypnea. METHODS: 182 children were enrolled. Each child had a chest X-ray that was read by two blinded, independent radiologists. Discordance between the two radiologists led to excluding 17 patients. The remaining 165 children were examined for fever and/or chest indrawing, and if they had a history of previous respiratory distress, challenge with a BD. The association of persistent tachypnea after BD and presence of pulmonary infiltrates was recorded. RESULTS: The median age was 22 months (mean 25.1 +- 14.5 mo) and 75.8% were aged greater than 1 year. There were 58.8% males. Previous respiratory distress occurred in 65.0% and 79.2% of children aged less than 1 year and 1 year, respectively. Pneumonia was radiologically diagnosed in 26/165 (15.8%). 2/40 (5 %) of children without a history of previous respiratory distress had pneumonia diagnosed. Of 125 children with history of previous respiratory distress, pneumonia was identified in 24 (19.2 %). Persistence of tachypnea after BD was associated with pulmonary infiltrate in 14/24 (58.3%), whereas, tachypnea persisted in 32/101 (31.7%) children without pulmonary infiltrates (P = 0.02). The negative predictive value of resolution of tachypnea was 87.3% (95% CI 77.5 93.4). BD non-response was most useful in children without fever and/or with chest indrawing to indicate pneumonia as the cause of the tachypnea. CONCLUSION: This study indicates that by adding the simple procedures of a history of previous respiratory distress, recording of fever and chest indrawing, and observing the response to bronchodilators, pneumonia can be reliably identified in children presenting with tachypnea and cough. It is probable that this approach to management of children with cough and tachypnea could reduce unnecessary use of antibiotics.

Evaluation of polymerization shrinkage of dental composites by an optical method.

This study proposes an alternative methodology for evaluating polymerization shrinkage of dental composites using an advanced video extensometer (AVE) system. This equipment measures the displacement between two points drawn on a tooth's wall without requiring physical contact with the tooth. By doing so, the polymerization process was monitored by the cusp deflection. This technique was used in human and bovine teeth, where the cavities were prepared under controlled conditions so that the volume of the composite used was the same in both types of teeth. After the cavity preparation, the specimens were acid etched, washed and dried, and then the adhesive was applied and polymerized. The composite was then inserted into the cavity. Polymerization was performed with two different light polymerizing units (LD Max and Optilight Max - Gnatus do Brasil), and the displacement curve of the tooth cusp was recorded for a period of 400 s. After a statistical analysis, it was concluded that the technique was capable of evaluating shrinkage by the deflection from the cusps and that the human and bovine teeth do not react in a similar manner towards the polymerization shrinkage of composites.

Chest radiograph abnormalities in patients hospitalized with leptospirosis in the city of Salvador, Bahia, Brazil.

This study was designed to estimate the prevalence of pulmonary radiograph abnormalities and describe the distribution of the patterns of radiographic alterations among patients hospitalized with leptospirosis. Chest radiographs of 139 patients hospitalized with leptospirosis in Couto Maia Hospital, in Salvador, Bahia, Brazil, between July, 1997, and July, 1999, were analyzed. The radiographs were requested soon after hospital admission, independent of the clinical manifestations of the patients. Only the first radiograph was considered. Pulmonary radiograph alterations were recorded in 35/139 patients (25.2%); 95% mid-point confidence interval = 18.5% to 32.9%. Among the patients with radiograph alterations, alveolar infiltrate was seen in 26/35 (74.3%). The lesions were bilateral in 54.3% and located in the inferior lobes in 45.5%. Pleural effusion, represented by blunting of the costo-phrenic angle, was detected in 8.6% of the patients. The pattern of the pulmonary alterations, predominantly bilateral alveolar infiltrates, is consistent with the evidence that the basic pulmonary alteration in leptospirosis is a generalized capillaritis.

Differences in evolution of children with non-severe acute lower respiratory tract infection with and without radiographically diagnosed pneumonia.

OBJECTIVE: To identify differences in the evolution of children with non-severe acute lower respiratory tract infection between those with and without radiographically diagnosed pneumonia. DESIGN: Prospective cohort study. SETTING: A public university pediatric hospital in Salvador, Northeast Brazil. PATIENTS: Children aged 2-59 months. METHODS: By active surveillance, the pneumonia cases were prospectively identified in a 2-year period. Each case was followed-up for changes in various clinical symptoms and signs. Demographic, clinical and radiographic data were recorded in standardized forms. Exclusion was due to antibiotic use in the previous 48 hours, signs of severe disease, refusal to give informed consent, underlying chronic illness, hospitalization in the previous 7 days or amoxicillin allergy. Chest X-ray (CXR) was later read by at least 2 independent pediatric radiologists. MAIN OUTCOME MEASURES: Radiographic diagnosed pneumonia based on agreed detection of pulmonary infiltrate or pleural effusion in 2 assessments. RESULTS: A total of 382 patients receiving amoxicillin were studied, of whom, 372 (97.4%) had concordant radiographic diagnosis which was pneumonia (52%), normal CXR (41%) and others (7%). By multivariate analysis, age (OR=1.03; 95% CI: 1.02-1.05), disease > 5 days (OR = 1.04; 95% CI: 1.001-1.08), reduced pulmonary expansion (OR = 3.3; 95% CI: 1.4-8.0), absence of wheezing (OR = 0.5; 95% CI: 0.3-0.9), crackles on admission (OR = 2.0; 95% CI: 1.2-3.5), inability to drink on day 1 (OR = 4.2; 95% CI: 1.05-17.3), consolidation percussion sign (OR = 7.0; 95% CI: 1.5-32.3), tachypnea (OR = 2.0; 95% CI: 1.09-3.6) and fever (OR = 3.6; 95% CI: 1.4-9.4) on day 2 were independently associated with pneumonia. The highest positive predictive value was at the 2nd day of evolution for tachypnea (71.0%) and fever (81.1%). CONCLUSION: Persistence of fever or tachypnea up to the second day of amoxicillin treatment is predictive of radiographically diagnosed pneumonia among children with non-severe lower respiratory tract diseases.

Characteristics of radiographically diagnosed pneumonia in under-5 children in Salvador, Brazil.

OBJECTIVE: To assess the association of demographic and clinical aspects with radiographically diagnosed pneumonia. DESIGN: By active surveillance, the admitted pneumonia cases by the pediatrician on duty were identified in a 2 year period. Demographic, clinical and radiographic data were registered into standardized forms. SETTING: A public university pediatric hospital in Salvador, Northeast Brazil. PATIENTS: Children <5 years-old. MAIN OUTCOME MEASURES: Radiographically diagnosed pneumonia based on detection of pulmonary infiltrate/ consolidation. RESULTS: 301 cases had the chest X-ray evaluated by a pediatric radiologist blinded to clinical information, among whom pulmonary infiltrate and consolidation were described in 161 (54%) and 119 (40%), respectively. Chest X-ray was read normal for 140 cases. Overall, the median age was 17 months (mean 20±14, range 12 days-59 months). Pulmonary infiltrate was less frequently described among patients aged under 1 year (41.3% vs 59.9%, P=0.002, OR [95% CI] = 0.47 [0.29-0.76]) and hyperinflation was significantly more frequent in this age group (27.9% vs 4.1%, P<0.001, OR [95% CI] = 9.14 [4.0-20.9]). By multiple logistic regression, fever on admission was independently associated with pulmonary infiltrate (OR [95% CI] = 1.68 [1.03-2.73]) or consolidation (1.79 [1.10-2.92]), wheezing was independently associated with absence of pulmonary infiltrate (0.53 [0.33-0.86]) or of consolidation (0.53 [0.33-0.87]). The positive likelihood ratio of fever on examination for pulmonary infiltrate and consolidation was 1.49 (95% CI:1.11-1.98) and 1.49 (95% CI: 1.14-1.94), respectively. CONCLUSION: Presence of fever enhanced 2.5 times the chance of children hospitalized with lower respiratory tract disease to have radiographically diagnosed pneumonia.

Aggressive behavior of papillary microcarcinoma in a patient with Graves' disease initially presenting as cystic neck mass.

Prognosis of papillary carcinoma of the thyroid associated with Graves' disease is controversial; nevertheless, tumors smaller than 1 cm (microcarcinoma) are usually considered to render a good prognosis. We describe a patient with Graves' disease who developed a lateral cystic neck mass that was later confirmed to be a metastatic lymph node from papillary thyroid microcarcinoma. Contrary to having a good prognosis with a microcarcinoma, our patient developed bilateral lung metastases. The possible role of thyroid stimulating immunoglobulins in the aggressive course of the tumor is discussed.

Polymorphism of 5HT2A serotonin receptor gene is implicated in smoking addiction.

Smoking behavior is influenced by genetic factors. Polymorphisms affecting the dopaminergic system have been linked to smoking habits. The aim of this study was to investigate if the T102C polymorphism of the 5-HT(2A) receptor gene is related to tobacco use, since this receptor modulates the mesolimbic dopamine system and the C allele is associated with reduced receptor gene expression. A sample of 625 subjects were genotyped and classified according to their smoking behavior (never, former, or current smokers). We found differences in the distribution of the genotypes when the current smokers were compared with the never + former smokers, suggesting that T102C polymorphism is associated with maintenance, but not with initiation of the smoking habit. The CC genotype was more frequent in the current smokers than in the never + former smokers (chi(2) = 6.825, P = 0.03). The odds ratio of being a current smoker with a CC genotype was 1.63, 95% CI 1.06-2.51.

Analysis of clinical studies with natural and synthetic luteinizing hormone-releasing hormone in man.

PIP: It was first determined that luteinizing hormone-releasing hormone (LH-RH) obtained from porcine, bovine, and ovine sources was biologically active in man. When the structure of porcine LH-RH was determined, synthetic material was also found active in man. Studies indicated that FSH as well as LH were released from the pituitary into the peripheral circulation by both the natural and synthetic LH-RH. Although blood basal levels of LH and FSH are increased after the menopause a further increase was produced by LH-RH, either naturally or synthetically. In other conditions (Klinefelter's and Turner's syndromes) with naturally occurring elevations of blood levels of LH and FSH, further release was also obtained by both natural and synthetic LH-RH. In subjects pretreated with 200 mg/day clomiphene additional rapid increase was obtained. In patients with pituitary tumors and acromegaly the response was variable. However, 1 patient who did not release gonadotropins after LH-RH did release thyrotropin (TSH) after receiving TSH-releasing hormone. The effects of LH-RH administration on other steroids in the blood are currently being investigated. Routes other than the intravenous administration are being tried, e.g., subcutaneous and intramuscular. It has been found that a child's pituitary can release LH and FSH after administration of porcine LH-RH. In Kallmann's syndrome of hypogonadotropic hypogonadism with anosmia, a small increase of gonadotropin release has been shown after rapid intravenous injection of LH-RH. Long duration of intravenous infusion of LH-RH with 2 supplementary intramuscular injections has produced ovulation in a patient primed with an FSH-containing material (Pergonal). In other experiments patients pretreated with clomiphene had an increased incidence of ovulation. In men with oligospermia only slight improvement has been obtained. Most of the data presented were obtained using highly purified material of porcine origin.^ieng

Cintilografia óssea trifásica para guiar a retirada de implantes metálicos em fraturas: estudo preliminar / Three-phase bone scintigraphy as a guide to metallic implant removal

O objetivo deste estudo foi avaliar o papel da cintilografia óssea trifásica na indicação da retirada do material de síntese de pacientes com fratura diafisária do fêmur, submetidos à fixação com haste intramedular bloqueada (HIB) ou com placa em ponte (PP), já que, atualmente, a indicação da retirada é feita por critérios não totalmente confiáveis. Foram estudados 13 pacientes, seis com colocação de HIB e sete com PP. Todos os pacientes foram submetidos a cintilografia óssea trifásica com 740MBq de MDP-99mTc em uma câmara de cintilação computadorizada. Em quatro pacientes (dois com HIB e dois com PP) houve retirada do material de síntese, em média, 42,2 meses após a fratura. Os pacientes com HIB apresentaram alterações discretas na fase tardia da cintilografia óssea e formação discreta do calo ósseo, enquanto os com PP mostraram alterações cintilográficas moderadas e formação anormal do calo ósseo. As discretas alterações descritas na cintilografia óssea nos pacientes com HlB indicam que este tipo de fixação leva a menor exigência mecânica do calo ósseo com remodelação mais fisiológica, comprovada pelo estudo tomográfico em dois pacientes, mostrando sua anatomia semelhante à do fêmur contralateral. Isto não ocorreu nos pacientes com PP, talvez devido a uma maior movimentação dos fragmentos ósseos permitida por este material. Esta movimentação sugere que este tipo de fixação talvez não seja o mais fisiológico, não proporcionando à fratura condições adequadas para se consolidar.