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1.
Expert Syst Appl ; 183: 115452, 2021 Nov 30.
Article in English | MEDLINE | ID: mdl-34177133

ABSTRACT

The COVID-19 pandemic, which originated in December 2019 in the city of Wuhan, China, continues to have a devastating effect on the health and well-being of the global population. Currently, approximately 8.8 million people have already been infected and more than 465,740 people have died worldwide. An important step in combating COVID-19 is the screening of infected patients using chest X-ray (CXR) images. However, this task is extremely time-consuming and prone to variability among specialists owing to its heterogeneity. Therefore, the present study aims to assist specialists in identifying COVID-19 patients from their chest radiographs, using automated computational techniques. The proposed method has four main steps: (1) the acquisition of the dataset, from two public databases; (2) the standardization of images through preprocessing; (3) the extraction of features using a deep features-based approach implemented through the networks VGG19, Inception-v3, and ResNet50; (4) the classifying of images into COVID-19 groups, using eXtreme Gradient Boosting (XGBoost) optimized by particle swarm optimization (PSO). In the best-case scenario, the proposed method achieved an accuracy of 98.71%, a precision of 98.89%, a recall of 99.63%, and an F1-score of 99.25%. In our study, we demonstrated that the problem of classifying CXR images of patients under COVID-19 and non-COVID-19 conditions can be solved efficiently by combining a deep features-based approach with a robust classifier (XGBoost) optimized by an evolutionary algorithm (PSO). The proposed method offers considerable advantages for clinicians seeking to tackle the current COVID-19 pandemic.

2.
Preprint in English | medRxiv | ID: ppmedrxiv-20173039

ABSTRACT

After four months of dealing with the pandemic, the city of Sao Paulo entered a phase of relaxed social-distancing measures in July 2020, and saw its social isolation rate fall at the same time as the number of cases, deaths, and hospital bed occupation declined. We use a calibrated multi-agent model to describe these dynamics. We assert here that this phenomenon can be understood as the result of local protective bubbles formed in the citys sub-environments at the same time that there was an exhaustion of contagion networks. Both reduce the velocity of the viruss spread, causing temporary reductions in the epidemic curve, albeit in an unstable equilibrium. These local bubbles can burst anytime and anywhere due to the reintroduction of a few infected people at the same time that there is a reduction in non-pharmaceutical interventions (NPI), such as social-distancing practices. It is important to stress that this hypothesis aligns with the dynamics of the viruss spread observed so far, without needing ad hoc suppositions about natural collective immunity thresholds or heterogeneity in the populations transmission rate, which come with the risk of making mistaken predictions that may could lead to the loss of many lives. The safe way to move ahead is to continue doing all we can to avoid new infections until a vaccine is found that properly and safely creates herd immunity.

3.
Anal Bioanal Chem ; 408(28): 8089-8098, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27595581

ABSTRACT

An analytical method based on a modified QuPPe (quick polar pesticide) extraction procedure coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was evaluated for the determination of four polar compounds (chlorate, fosetyl-Al, maleic hydrazide, and perchlorate) in nutraceutical products obtained from soy. Experimental conditions including extraction such as solvent, acidification, time, and clean-up sorbents were varied. Acidified acetonitrile (1 % formic acid, v/v) was used as extraction solvent instead of methanol (conventional QuPPe), which provides a doughy mixture which cannot be injected into the LC. Clean-up or derivatization steps were avoided. For analysis, several stationary phases were evaluated and Hypercarb (porous graphitic carbon) provided the best results. The optimized method was validated and recoveries ranged between 46 and 119 %, and correction factors can be used for quantification purposes bearing in mind that inter-day precision was equal to or lower than 17 %. Limits of quantification (LOQs) ranged from 4 to 100 µg kg-1. Soy-based nutraceutical products were analyzed and chlorate was detected in five samples at concentrations between 63 and 1642 µg kg-1. Graphical Abstract Analysis of polar compounds in soy-based nutraceutical products.


Subject(s)
Dietary Supplements/analysis , Drug Contamination , Glycine max/chemistry , Pesticide Residues/analysis , Capsules , Chromatography, Liquid , Drug Contamination/prevention & control , Limit of Detection , Reproducibility of Results , Tablets , Tandem Mass Spectrometry , Time Factors
4.
RSBO (Impr.) ; 11(3): 293-302, Jul.-Sep. 2014. tab
Article in English | LILACS | ID: lil-778294

ABSTRACT

Introduction: A problem of endodontic origin is solved mainly by cleaning and disinfecting the root canal system. However, the use of medicines for systemic use is a great auxiliary in combating pain, inflammation and/or infection, making easier to treat the clinical status, that patient experiences less pain. Objective: To conduct a literature review evidencing the clinical indications of systemic medication application in endodontics, to aid the professional in achieving more effective and safer therapeutics. Literature review: There is a wide variety of drugs available on market. Consequently, the dentist is uncertain when prescribing systemic medication because a pharmacological arsenal is available. Also, the dentist frequently does not know the mechanism of action of these drugs and their interactions. Additionally to analgesics, anti-inflammatories and antibiotics, used to combat pain, inflammation and infection, respectively, dentists can still make use of anxiolytics, in cases of patients very fearful to endodontic treatment. Conclusion: It is of fundamental importance that the dentist knows about the medication type to be used in each case and whether systemic therapy is really necessary, through a comprehensive case evaluation.

5.
Sensors (Basel) ; 13(7): 9174-82, 2013 Jul 17.
Article in English | MEDLINE | ID: mdl-23867743

ABSTRACT

Vibratory feeders or vibratory conveyors have been widely used for the transport and orientation of individual parts and bulk materials in many branches of industrial activity. From the designer's standpoint, the current endeavor is to conceive efficient vibratory feeders, satisfying constraints of power consumption, vibration transmission and noise emission. Moreover, the interest in the reduction of maintenance cost is always present. In this context, this paper investigates experimentally the concept of vibratory conveying based on the use of piezoelectric materials for motion generation. A small-size prototype of a linear conveyor, in which lead-zirconate-titanate (PZT) patches are bonded to the resilient elements, is described. One of the main design goals is that the prototype is intended to be fed directly from the electric network, aiming at avoiding the use of electronic equipment for driving. To comply with this feature and, at the same time, enable to adjust the transport velocity, a mechanical device has been conceived in such a way that the first natural frequency of the conveyor can be changed. It is shown that the transport velocity is determined by the proximity between the excitation frequency and the first natural frequency of the conveyor. The experimental tests performed to characterize the dynamic behavior of the prototype are described and the range of transport velocities is determined.


Subject(s)
Micro-Electrical-Mechanical Systems/instrumentation , Transducers , Transportation/instrumentation , Equipment Design , Equipment Failure Analysis , Vibration
6.
Rev Soc Bras Med Trop ; 46(1): 88-91, 2013.
Article in English | MEDLINE | ID: mdl-23563832

ABSTRACT

INTRODUCTION: While the incidence of HIV infection and AIDS is increasing in small Brazilian cities, epidemiological studies are often conducted in large urban centers. METHODS: Our group conducted a retrospective analysis of survival determinants among 358 patients who attended a reference unit in a small city. RESULTS: Death risk was lower among men that had sex with men, patients with an HIV-seropositive partner, and those admitted after highly active antiretroviral therapy (HAART) was available. CONCLUSIONS: The study documents the striking beneficial effect of HAART. The finding of other groups with improved survival may aid in the development of programmatic strategies.


Subject(s)
Antiretroviral Therapy, Highly Active , HIV Infections/mortality , Adult , Brazil/epidemiology , Cohort Studies , Female , HIV Infections/drug therapy , Humans , Male , Retrospective Studies , Survival Analysis
7.
Rev. Soc. Bras. Med. Trop ; 46(1): 88-91, Jan.-Feb. 2013. graf, tab
Article in English | LILACS | ID: lil-666801

ABSTRACT

INTRODUCTION: While the incidence of HIV infection and AIDS is increasing in small Brazilian cities, epidemiological studies are often conducted in large urban centers. METHODS: Our group conducted a retrospective analysis of survival determinants among 358 patients who attended a reference unit in a small city. RESULTS: Death risk was lower among men that had sex with men, patients with an HIV-seropositive partner, and those admitted after highly active antiretroviral therapy (HAART) was available. CONCLUSIONS: The study documents the striking beneficial effect of HAART. The finding of other groups with improved survival may aid in the development of programmatic strategies.


Subject(s)
Adult , Female , Humans , Male , Antiretroviral Therapy, Highly Active , HIV Infections/mortality , Brazil/epidemiology , Cohort Studies , HIV Infections/drug therapy , Retrospective Studies , Survival Analysis
8.
Arq. bras. cardiol ; 99(3): 825-833, set. 2012. ilus, tab
Article in Portuguese | LILACS | ID: lil-649260

ABSTRACT

FUNDAMENTO: A radiografia de tórax e o eletrocardiograma (ECG) tem sido criticados em razão de sua baixa sensibilidade no diagnóstico da Hipertrofia Ventricular Esquerda (HVE) quando comparada ao ecocardiograma. Entretanto, esse exame não está disponível nos centros de atendimento primário para toda a população de hipertensos. OBJETIVO: Avaliar se a radiografia de tórax associada ao eletrocardiograma apresenta acurácia que justifique seu uso na detecção de HVE em hipertensos, bem como a utilidade do índice cardiotorácico e das radiografias oblíquas na avaliação das dimensões das câmaras cardíacas esquerdas. MÉTODOS: Estudo prospectivo realizado em 177 pacientes hipertensos consecutivos, através da radiografia do tórax, eletrocardiograma e ecocardiograma. Testes de acurácia foram utilizados para comparar esses métodos utilizando a ecocardiografia convencional como padrão de referência. RESULTADOS: O índice cardiotorácico mostrou sensibilidade de 17% para o diagnóstico de HVE, somente detectando alterações cardíacas mais acentuadas. As incidências póstero-anterior e perfil tiveram sensibilidade de 52%, aumentando para 54% quando a radiografia de tórax foi associada ao eletrocardiograma. As incidências oblíquas não melhoraram significativamente a acurácia da radiografia de tórax que, por sua vez, apresentou alta especificidade e boa sensibilidade para a detecção do aumento da aorta. Foi interessante notar que essa alteração estava presente em metade dos hipertensos com HVE. CONCLUSÃO: A associação da radiografia de tórax com eletrocardiograma é útil na avaliação inicial de hipertensos para o diagnóstico de hipertrofia ventricular esquerda, especialmente se a ecocardiografia não estiver disponível. (Arq Bras Cardiol. 2012; [online].ahead print, PP.0-0).


BACKGROUND: Chest radiography and electrocardiogram have been criticized due to their low sensitivity for Left Ventricular Hypertrophy diagnosis compared to echocardiogram. This one, however, is not available in primary health care centers to all hypertensive population. OBJECTIVE: To evaluate whether the association chest radiography-electrocardiogram provides the accuracy to justify its use in left ventricular hypertrophy detection in hypertensive patients, as well as the usefulness of the cardiothoracic ratio and oblique radiographs in relation to frontal and lateral views in evaluating dimensions of left cardiac chambers. METHODS: This was a prospective study including 177 consecutive hypertensive patients through chest radiography, electrocardiogram and echocardiography. Accuracy test was used to compare these methods using echocardiography as gold standard. RESULTS: The cardiothoracic ratio showed 17% sensitivity for detection of left ventricular hypertrophy, only indicating cardiac alterations at an advanced stage. Frontal plus lateral views showed sensitivity of 52%, which rose to 54% when chest radiography was associated with electrocardiogram. The oblique views did not significantly improve chest radiography accuracy. Chest radiography presented high specificity and elevated sensitivity for detection of aortal enlargement. Interestingly, this alteration was present in half of the hypertensive patients with left ventricular hypertrophy. CONCLUSION: We conclude that the association chest radiography-electrocardiogram is useful for the screening of hypertensive patients for the diagnosis of left ventricular hypertrophy, especially if echocardiogram is unavailable. (Arq Bras Cardiol. 2012; [online].ahead print, PP.0-0).


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Young Adult , Hypertension/complications , Hypertrophy, Left Ventricular , Cross-Sectional Studies , Electrocardiography , Hypertrophy, Left Ventricular , Prospective Studies , Radiography, Thoracic , Sensitivity and Specificity
9.
Arq Bras Cardiol ; 99(3): 825-33, 2012 Sep.
Article in English, Portuguese | MEDLINE | ID: mdl-22858617

ABSTRACT

BACKGROUND: Chest radiography and electrocardiogram have been criticized due to their low sensitivity for Left Ventricular Hypertrophy diagnosis compared to echocardiogram. This one, however, is not available in primary health care centers to all hypertensive population. OBJECTIVE: To evaluate whether the association chest radiography-electrocardiogram provides the accuracy to justify its use in left ventricular hypertrophy detection in hypertensive patients, as well as the usefulness of the cardiothoracic ratio and oblique radiographs in relation to frontal and lateral views in evaluating dimensions of left cardiac chambers. METHODS: This was a prospective study including 177 consecutive hypertensive patients through chest radiography, electrocardiogram and echocardiography. Accuracy test was used to compare these methods using echocardiography as gold standard. RESULTS: The cardiothoracic ratio showed 17% sensitivity for detection of left ventricular hypertrophy, only indicating cardiac alterations at an advanced stage. Frontal plus lateral views showed sensitivity of 52%, which rose to 54% when chest radiography was associated with electrocardiogram. The oblique views did not significantly improve chest radiography accuracy. Chest radiography presented high specificity and elevated sensitivity for detection of aortal enlargement. Interestingly, this alteration was present in half of the hypertensive patients with left ventricular hypertrophy. CONCLUSION: We conclude that the association chest radiography-electrocardiogram is useful for the screening of hypertensive patients for the diagnosis of left ventricular hypertrophy, especially if echocardiogram is unavailable.


Subject(s)
Hypertension/complications , Hypertrophy, Left Ventricular/diagnostic imaging , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Electrocardiography , Female , Humans , Male , Middle Aged , Prospective Studies , Radiography, Thoracic , Sensitivity and Specificity , Ultrasonography , Young Adult
11.
Article in English | LILACS, VETINDEX | ID: lil-542424

Subject(s)
Hospitals/trends
12.
Braz. j. vet. res. anim. sci ; 46(3): 207-214, 2009. graf, tab, ilus
Article in English | LILACS | ID: lil-536858

ABSTRACT

The ELISA technique was used to evaluate and compare young ovine humoral immune response during crotalic antiserum production. Animals were clinically evaluated throughout this process, and the neutralizing capacity of antisera raised against natural (NV) and Cobalt-60 irradiated (IrV) venoms of Crotalus durissus terrificus (C.d.t.) was verified by means of in vitro challenges. Three groups of six animals each were used: G1 received NV; G2 was inoculated with IrV; and G3 was used as control. Animals received six immunizations during 84 days at 14-day intervals. ELISA of antibody profile showed significant difference (p<5%) between experimental groups (G1

A técnica de Elisa foi utilizada para avaliar e comparar a resposta imune humoral de ovinos jovens para a produção de soro anticrotálico. Durante o processo de soroprodução, foi realizada a avaliação clínica dos animais. A capacidade de neutralização do soro produzido a partir de veneno de serpente Crotalus durissus terrificus, nativo (VN) e irradiado (VIr) com Cobalto–60 foi verificada por meio de desafios in vitro. Um grupo de seis animais recebeu veneno nativo, o segundo grupo recebeu veneno irradiado e o terceiro grupo foi o controle. Os animais receberam seis imunizações durante 84 dias com intervalo de14 dias. Houve diferença significativa (p<5%) no teste de ELISA do perfil de anticorpos produzidos pelos grupos experimentais (VN

Subject(s)
Animals , Antibodies/therapeutic use , Crotalus/immunology , Radiation , Sheep , Crotalid Venoms/toxicity , Crotalid Venoms/therapeutic use
13.
Rev. Assoc. Paul. Cir. Dent ; 62(6): 476-480, nov.-dez. 2008. ilus
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-535069

ABSTRACT

O presente relato descreve o tratamento endodôntico não-cirúrgico de um incisivo lateral superior direito portador da malformação conhecida como dens invaginatus, com lesão periapical e ápice incompletamente formado. O tratamento realizado com medicação intracanal prolongada com pasta de hidróxido de cálcio/iodofórmio e propilenoglicol, e obturação definitiva do canal radicular com cimento Sealapex conduziu ao sucesso clínico, representado pelo reparo da lesão periapical e apicificação.


This case report describes a nonsurgical endodontic treatment of dens invaginatus in a maxillary right lateral incisor with periradicular lesion and incompletely formed apex. The treatment realized with a long-term intracanal dressing with calcium hydroxide paste with iodoform and propylene glicol and definitive filling of the root canal with Sealapex sealer, leaded to the clinical success, represented by the periradicular lesion healing and apicification.


Subject(s)
Humans , Female , Adolescent , Dens in Dente/rehabilitation , Endodontics , Calcium Hydroxide
14.
Rev. Assoc. Paul. Cir. Dent ; 62(2): 128-134, mar.-abr. 2008. ilus
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-533577

ABSTRACT

Assim como a infiltração marginal apical, a infiltração marginal coronária também vem sendo salientada e destacada com a publicação de numerosos trabalhos na literatura mais recente. Porém, houve um alerta para o assunto desde o século passado, quando se verificou que os materiais restauradores definitivos ou temporários têm as suas limitações. O presente relato aborda o problema da infiltração coronária em dentes tratados endodonticamente, decorrente de uma restauração definitiva inadequada. Aponta, ainda, para a necessidade de um tratamento endodôntico que vede hermeticamente todo o sistema de canais radiculares, bem como a durabilidade e eficiência dos materiais restauradores provisórios e definitivos. Aborda, por fim, outro fator complicador, quando o paciente não procura o profissional para completar o tratamento restaurador da coroa dentária.


As well as apicalleakage, coronary leakage have also recently acquired its due importance. However, such theme has been reported since last century, and it is well known that definitive or temporary restoring materiaIs have their limitations. This paper analyses this controversial subject, coronary leakage in endodontically treated teeth, as a result or not of definitive sealing. It also points out to the necessity of an endodontic approach that can hermetically seal all the root canal system, as well as to the durability and efficiency ofthe temporary and definitive restoring material. Itfinally approaches a complicatingfactor, thefact that the patient do not seekfor professional help to comply with the complete restoration of dental crown.


Subject(s)
Dental Pulp Cavity , Infiltration-Percolation
15.
Rev Soc Bras Med Trop ; 40(5): 516-20, 2007.
Article in Portuguese | MEDLINE | ID: mdl-17992405

ABSTRACT

The aim of this study was to look for evidence of vector transmission of Chagas disease, in and around the homes of individuals living in municipalities in the Botucatu region who presented a positive xenodiagnosis. Fifty-eight subjects were studied and blood samples were collected from them for laboratory analysis. The results from this study showed that the individuals in both groups presented low formal education levels and had been working in unskilled professions There was a slight predominance of females. In comparison with previous conditions, it was observed that there had been a slight improvement in the subjects' housing conditions, but on the other hand there had been an increase in the numbers of individuals living in rural areas. Subjects born before 1983 presented statistically greater knowledge of and contact with triatomines than did those born from 1983 onwards. Analysis and comparison of the results from the serological tests, including indirect passive hemagglutination, indirect immunofluorescence and immunoenzymatic assay, showed that ELISA presented greatest sensitivity. The results from this study have shown that the population born from 1983 onwards did not know about the transmission vector for Chagas disease.


Subject(s)
Chagas Disease/epidemiology , Health Knowledge, Attitudes, Practice , Insect Vectors , Triatominae , Adolescent , Adult , Aged , Animals , Brazil/epidemiology , Chagas Disease/diagnosis , Chagas Disease/transmission , Child , Female , Humans , Male , Middle Aged , Prevalence , Rural Population , Seroepidemiologic Studies
16.
Rev. Soc. Bras. Med. Trop ; 40(5): 516-520, out. 2007.
Article in Portuguese | LILACS | ID: lil-467009

ABSTRACT

O objetivo deste estudo foi o de procurar evidências da transmissão vetorial da doença de Chagas, nos domicílios e peridomicílios de indivíduos residentes em municípios da região de Botucatu, que tiveram xenodiagnóstico positivos. Foram estudados 58 indivíduos e foi coletada amostra do sangue para a realização de exames laboratoriais. Os resultados deste estudo mostraram que os indivíduos, de ambos os grupos, tinham baixa escolaridade e exerciam profissões que não exigiam qualificações técnicas. Houve discreto predomínio de indivíduos do sexo feminino. Quando comparadas às condições anteriores, verificou-se que houve discreta melhora nas condições de habitação, por outro lado, houve aumento de moradores em zona rural. Os indivíduos nascidos antes de 1983, apresentaram conhecimento e contato com triatomídeo estaticamente mais elevado quando comparado com os nascidos a partir 1983. A análise e comparação dos resultados das sorologias, referentes aos hemaglutinação passiva indireta, imunofluorescência indireta e ensaio imunoenzimático, mostrou que o ELISA apresentou maior sensibilidade. Os resultados deste estudo mostram que a população nascida a partir de 1983 não conhecia o vetor transmissor da doença de Chagas.


The aim of this study was to look for evidence of vector transmission of Chagas disease, in and around the homes of individuals living in municipalities in the Botucatu region who presented a positive xenodiagnosis. Fifty-eight subjects were studied and blood samples were collected from them for laboratory analysis. The results from this study showed that the individuals in both groups presented low formal education levels and had been working in unskilled professions There was a slight predominance of females. In comparison with previous conditions, it was observed that there had been a slight improvement in the subjects' housing conditions, but on the other hand there had been an increase in the numbers of individuals living in rural areas. Subjects born before 1983 presented statistically greater knowledge of and contact with triatomines than did those born from 1983 onwards. Analysis and comparison of the results from the serological tests, including indirect passive hemagglutination, indirect immunofluorescence and immunoenzymatic assay, showed that ELISA presented greatest sensitivity. The results from this study have shown that the population born from 1983 onwards did not know about the transmission vector for Chagas disease.


Subject(s)
Adolescent , Adult , Aged , Animals , Child , Female , Humans , Male , Middle Aged , Chagas Disease/epidemiology , Health Knowledge, Attitudes, Practice , Insect Vectors , Triatominae , Brazil/epidemiology , Chagas Disease/diagnosis , Chagas Disease/transmission , Prevalence , Rural Population , Seroepidemiologic Studies
17.
Braz J Infect Dis ; 11(2): 226-33, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17625767

ABSTRACT

Despite the existence of highly sensitive tests, inconclusive serological results are frequent in chronic chagasic infection. This study aimed to define a diagnostic conduct for 30 individuals with inconclusive serology (G3) for chagasic infection assisted at the Outpatient Unit for Infectious and Parasitic Diseases of the Botucatu School of Medicine. Twenty-one individuals with negative serology (G1) and 33 with positive serology (G2) were also studied. Serological methods ELISA, HAI, IFI and immunoblotting TESA-cruzi were used for G1, G2 and G3, and parasitological methods xenodiagnosis, hemoculture and PCR-LIT were used for G2 and G3 individuals. ELISA, HAI and IFI were performed in 5 different blood samples in G2 and G3. TESA-cruzi was carried out only once in G1, G2 and G3 and, since it is the most sensitive, it was utilized as standard. In G3, positivity for ELISA reached 86% in the fifth blood sample; the ELISA+HAI+IFI combination showed a maximum of 44.8% in the second sample; and TESA-cruzi, 76% in one single sample. Xenodiagnosis positivity was 9.4%; hemoculture showed 15.2%; and PCR-LIT exhibited 22% positivity in G2. Nevertheless, in G3, positivity percentage was 3.4% for xenodiagnosis, 6.7% for PCR-LIT, and no positive result was found for hemoculture. In G3, PCR-LIT resolved one case which was still inconclusive according to serology tests. In order to define inconclusive diagnoses, the results suggest the combined use of ELISA+HAI+IFI in 2 blood samples, decreasing the occurrence of false positive/negative results. If results remain inconclusive, the performance of TESA-cruzi and PCR-LIT, if necessary, is recommended.


Subject(s)
Chagas Disease/diagnosis , Trypanosoma cruzi/genetics , Trypanosoma cruzi/immunology , Animals , Case-Control Studies , Chronic Disease , Female , Humans , Male , Polymerase Chain Reaction , Sensitivity and Specificity , Serologic Tests , Xenodiagnosis
18.
Braz. j. infect. dis ; 11(2): 226-233, Apr. 2007. graf, ilus, tab
Article in English | LILACS | ID: lil-454724

ABSTRACT

Despite the existence of highly sensitive tests, inconclusive serological results are frequent in chronic chagasic infection. This study aimed to define a diagnostic conduct for 30 individuals with inconclusive serology (G3) for chagasic infection assisted at the Outpatient Unit for Infectious and Parasitic Diseases of the Botucatu School of Medicine. Twenty-one individuals with negative serology (G1) and 33 with positive serology (G2) were also studied. Serological methods ELISA, HAI, IFI and immunoblotting TESA-cruzi were used for G1, G2 and G3, and parasitological methods xenodiagnosis, hemoculture and PCR-LIT were used for G2 and G3 individuals. ELISA, HAI and IFI were performed in 5 different blood samples in G2 and G3. TESA-cruzi was carried out only once in G1, G2 and G3 and, since it is the most sensitive, it was utilized as standard. In G3, positivity for ELISA reached 86 percent in the fifth blood sample; the ELISA+HAI+IFI combination showed a maximum of 44.8 percent in the second sample; and TESA-cruzi, 76 percent in one single sample. Xenodiagnosis positivity was 9.4 percent; hemoculture showed 15.2 percent; and PCR-LIT exhibited 22 percent positivity in G2. Nevertheless, in G3, positivity percentage was 3.4 percent for xenodiagnosis, 6.7 percent for PCR-LIT, and no positive result was found for hemoculture. In G3, PCR-LIT resolved one case which was still inconclusive according to serology tests. In order to define inconclusive diagnoses, the results suggest the combined use of ELISA+HAI+IFI in 2 blood samples, decreasing the occurrence of false positive/negative results. If results remain inconclusive, the performance of TESA-cruzi and PCR-LIT, if necessary, is recommended.


Subject(s)
Animals , Female , Humans , Male , Chagas Disease/diagnosis , Trypanosoma cruzi/genetics , Trypanosoma cruzi/immunology , Case-Control Studies , Chronic Disease , Polymerase Chain Reaction , Sensitivity and Specificity , Serologic Tests , Xenodiagnosis
19.
J. bras. pneumol ; 32(5): 438-443, set.-out. 2006. tab
Article in Portuguese | LILACS | ID: lil-452401

ABSTRACT

OBJETIVO: Avaliar os resultados do teste tuberculínico e relacioná-los com a presença ou não de tuberculose em atividade e com a contagem de linfócitos T CD4+/CD8+. MÉTODOS: Foram revisados 802 prontuários de pacientes com síndrome da imunodeficiência adquirida atendidos no período de agosto de 1985 a março de 2003. Cento e oitenta e cinco pacientes realizaram o teste tuberculínico (23,1 por cento) e, destes, 107 eram do sexo masculino (57,8 por cento). A média de idade no grupo de reatores ao teste tuberculínico foi de 30,6 anos, com desvio-padrão de 6,62 anos, e entre os não reatores de 34,45 anos com desvio-padrão de 10,32 anos. Foram constituídos dois grupos de estudo: reatores ao teste tuberculínico, com 28 pacientes, e não reatores ao teste tuberculínico, com 157 pacientes. RESULTADOS: Grande parte dos indivíduos foi pouco responsiva ao teste tuberculínico. Constatou-se, no grupo de reatores, maior porcentagem de indivíduos com tuberculose ativa à época da realização do teste, quando se comparou com os não reatores. Dez pacientes entre os reatores e onze entre os não reatores apresentavam alguma forma clínica de tuberculose em atividade à época da realização do teste, sendo que seis do primeiro grupo e oito do segundo tinham contagem de linfócitos T CD4+ menor que 200 células/mm³. CONCLUSÃO: Indurações maiores do que 5 mm não se relacionaram com contagens absolutas mais altas de células T CD4+.


OBJECTIVE: To evaluate tuberculin test results and relate them to the presence or absence of active tuberculosis, as well as to CD4+ and CD8+ T-lymphocyte counts. METHOD: The charts of 802 patients with acquired immunodeficiency syndrome treated between August of 1985 and March of 2003 were reviewed. Of the 185 patients submitted to tuberculin tests (23.1 percent), 107 (57.8 percent) were male, and 78 (42.2 percent) were female. Patients were divided into two study groups: tuberculin test reactors (n = 28); and tuberculin test non-reactors (n = 157). Among the reactors, the mean age was 30.60 years, with a standard deviation of 6.62 years, compared with 34.45 years, with a standard deviation of 10.32 years, among the non-reactors. RESULTS: Most of the individuals tested presented only a mild response to the tuberculin test. We found that, at the time of the test, the percentage of individuals with active tuberculosis was greater in the reactor group than in the non-reactor group. During the test period, 10 reactor group patients and 11 non-reactor group patients presented some clinical form of active tuberculosis. In addition, CD4+ T-lymphocyte counts were lower than 200 cells/mm³ in 6 reactor group patients and in 8 non-reactor group patients. CONCLUSION: Indurations greater than 5 mm were unrelated to higher absolute CD4+ T-cell counts.


Subject(s)
Adult , Female , Humans , Male , AIDS-Related Opportunistic Infections/diagnosis , Tuberculosis, Pulmonary/diagnosis , AIDS-Related Opportunistic Infections/immunology , Retrospective Studies , Tuberculin Test , Tuberculosis, Pulmonary/immunology
20.
J Bras Pneumol ; 32(5): 438-43, 2006.
Article in English, Portuguese | MEDLINE | ID: mdl-17268748

ABSTRACT

OBJECTIVE: To evaluate tuberculin test results and relate them to the presence or absence of active tuberculosis, as well as to CD4+ and CD8+ T-lymphocyte counts. METHOD: The charts of 802 patients with acquired immunodeficiency syndrome treated between August of 1985 and March of 2003 were reviewed. Of the 185 patients submitted to tuberculin tests (23.1%), 107 (57.8%) were male, and 78 (42.2%) were female. Patients were divided into two study groups: tuberculin test reactors (n = 28); and tuberculin test non-reactors (n = 157). Among the reactors, the mean age was 30.60 years, with a standard deviation of 6.62 years, compared with 34.45 years, with a standard deviation of 10.32 years, among the non-reactors. RESULTS: Most of the individuals tested presented only a mild response to the tuberculin test. We found that, at the time of the test, the percentage of individuals with active tuberculosis was greater in the reactor group than in the non-reactor group. During the test period, 10 reactor group patients and 11 non-reactor group patients presented some clinical form of active tuberculosis. In addition, CD4+ T-lymphocyte counts were lower than 200 cells/mm(3) in 6 reactor group patients and in 8 non-reactor group patients. CONCLUSION: Indurations greater than 5 mm were unrelated to higher absolute CD4+ T-cell counts.


Subject(s)
AIDS-Related Opportunistic Infections/diagnosis , CD4-CD8 Ratio , Tuberculosis, Pulmonary/diagnosis , AIDS-Related Opportunistic Infections/immunology , Adult , Female , Humans , Male , Retrospective Studies , Tuberculin Test , Tuberculosis, Pulmonary/immunology
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