Validation of a Brazilian Portuguese Version of the Walking Estimated-Limitation Calculated by History (WELCH)

Abstract Background: The Walking Estimated-Limitation Calculated by History (WELCH) questionnaire has been proposed to evaluate walking impairment in patients with intermittent claudication (IC), presenting satisfactory psychometric properties. However, a Brazilian Portuguese version of the questionnaire is unavailable, limiting its application in Brazilian patients. Objective: To analyze the psychometric properties of a translated Brazilian Portuguese version of the WELCH in Brazilian patients with IC. Methods: Eighty-four patients with IC participated in the study. After translation and back-translation, carried out by two independent translators, the concurrent validity of the WELCH was analyzed by correlating the questionnaire scores with the walking capacity assessed with the Gardner treadmill test. To determine the reliability of the WELCH, internal consistency and test–retest reliability with a seven-day interval between the two questionnaire applications were calculated. Results: There were significant correlations between the WELCH score and the claudication onset distance (r = 0.64, p = 0.01) and total walking distance (r = 0.61, p = 0.01). The internal consistency was 0.84 and the intraclass correlation coefficient between questionnaire evaluations was 0.84. There were no differences in WELCH scores between the two questionnaire applications. Conclusion: The Brazilian Portuguese version of the WELCH presents adequate validity and reliability indicators, which support its application to Brazilian patients with IC.

Polymerase chain reaction with two molecular targets in mucosal leishmaniasis' diagnosis: a validation study

We validated the polymerase chain reaction (PCR) with a composite reference standard in 61 patients clinically suspected of having mucosal leishmaniasis, 36 of which were cases and 25 were non-cases according to this reference standard. Patient classification and test application were carried out independently by two blind observers. One pair of primers was used to amplify a fragment of 120 bp in the conserved region of kDNA and another pair was used to amplify the internal transcript spacers (ITS) rDNA. PCR showed 68.6% (95% CI 59.2-72.6) sensitivity and 92% (95% CI 78.9-97.7) specificity; positive likelihood ratio: 8.6 (95% CI 2.8-31.3) and negative likelihood ratio: 0.3 (95% CI 0.3-0.5), when kDNA molecular target was amplified. The test performed better on sensitivity using this target compared to the ITS rDNA molecular target which showed 40% (95% CI 31.5-42.3) sensitivity and 96% (95% CI 84.1-99.3) specificity; positive likelihood ratio: 10 (95% CI 2.0-58.8) and negative likelihood ratio: 0.6 (95% CI 0.6-0.8). The inter-observer agreement was excellent for both tests. Based upon results obtained and due to low performance of conventional methods for diagnosing mucosal leishmaniasis, we consider PCR with kDNA as molecular target is a useful diagnostic test and the ITS rDNA molecular target is useful when the aim is to identify species.

Cl gene cluster encoding several small nucleolar RNAs: a comparison amongst trypanosomatids

Small nucleolar RNAs (snoRNAs) are small non-coding RNAs that modify RNA molecules such as rRNA and snRNA by guiding 2'-O-ribose methylation (C/D box snoRNA family) and pseudouridylation reactions (H/ACA snoRNA family). H/ACA snoRNAs are also involved in trans-splicing in trypanosomatids. The aims of this work were to characterise the Cl gene cluster that encodes several snoRNAs in Trypanosoma rangeli and compare it with clusters from Trypanosoma cruzi, Trypanosoma brucei, Leishmania major, Leishmania infantum, Leishmania braziliensis and Leptomonas collosoma. The T. rangeli Cl gene cluster is an 801 base pair (bp) repeat sequence that encodes three C/D (Cl1, Cl2 and Cl4) and three H/ACA (Cl3, Cl5 and Cl6) snoRNAs. In contrast to T. brucei, the Cl3 and Cl5 homologues have not been annotated in the Leishmania or T. cruzi genome projects (http//:www.genedb.org). Of note, snoRNA transcribed regions have a high degree of sequence identity among all species and share gene synteny. Collectively, these findings suggest that the Cl cluster could constitute an interesting target for therapeutic (gene silencing) or diagnostic intervention strategies (PCR-derived tools).

Anti-Toxoplasma gondii secretory IgA in tears of patients with ocular toxoplasmosis: immunodiagnostic validation by ELISA

Toxoplasma gondii causes posterior uveitis and the specific diagnosis is based on clinical criteria. The presence of anti-T. gondii secretory IgA (sIgA) antibodies in patients' tears has been reported and an association was found between ocular toxoplasmosis and the anti-T. gondii sIgA isotype in Brazilian patients. The purpose of this study was to provide an objective validation of the published ELISA test for determining the presence of anti-T. gondii sIgA in the tears of individuals with ocular toxoplasmosis. Tears from 156 patients with active posterior uveitis were analysed; 82 of them presented characteristics of ocular toxoplasmosis (standard lesion) and 74 patients presented uveitis due to other aetiologies. Cases of active posterior uveitis were considered standard when a new inflammatory focus satellite to old retinochoroidal scars was observed. The determination of anti-T. gondii sIgA was made using an ELISA test with crude tachyzoite antigenic extracts. Tears were collected without previous stimulation. Detection of sIgA showed 65.9% sensitivity (95% CI = 54.5-74.4), 71.6% specificity (95% CI = 59.8-81.2), a positive predictive value of 72% (95% CI = 60.3-81.5) and a negative predictive value of 65.4% (95% CI = 54.0-75.4). sIgA reactivity was higher in the tears of patients with active posterior uveitis due to T. gondii (p < 0.05). The test is useful for differentiating active posterior uveitis due to toxoplasmosis from uveitis caused by other diseases.

Validation of an immunochromatographic assay kit for the identification of the Mycobacterium tuberculosis complex

The performance of the immunochromatographic assay, SD BIOLINE TB Ag MPT64 RAPID®, was evaluated in Madagascar. Using mouse anti-MPT64 monoclonal antibodies for rapid discrimination between the Mycobacterium tuberculosis complex and nontuberculous mycobacteria, the kit was tested on mycobacteria and other pathogens using conventional methods as the gold standard. The results presented here indicate that this kit has excellent sensitivity (100%) and specificity (100%) compared to standard biochemical detection and can be easily used for the rapid identification of M. tuberculosis complex.

Validation of a modified fluorimetric assay for the screening of trichomonacidal drugs

A fluorimetric microassay that uses a redox dye to determine the viability of the flagellate Trichomonas vaginalis has been optimised to provide a more sensitive method to evaluate potential trichomonacidal compounds. Resazurin has been used in recent years to test drugs against different parasites, including trichomonadid protozoa; however, the reproducibility of these resazurin-based methods in our laboratory has been limited because the flagellate culture medium spontaneously reduces the resazurin. The objective of this work was to refine the fluorimetric microassay method previously developed by other research groups to reduce the fluorescence background generated by the media and increase the sensitivity of the screening assay. The experimental conditions, time of incubation, resazurin concentration and media used in the microtitre plates were adjusted. Different drug sensitivity studies against T. vaginalis were developed using the 5-nitroimidazole reference drugs, new 5-nitroindazolinones and 5-nitroindazole synthetic derivatives. Haemocytometer count results were compared with the resazurin assay using a 10% solution of 3 mM resazurin dissolved in phosphate buffered saline with glucose (1 mg/mL). The fluorimetric assay and the haemocytometer counts resulted in similar percentages of trichomonacidal activity in all the experiments, demonstrating that the fluorimetric microtitre assay has the necessary accuracy for high-throughput screening of new drugs against T. vaginalis.

Development and validation of PCR-based assays for diagnosis of American cutaneous leishmaniasis and identificatio nof the parasite species

In this study, PCR assays targeting different Leishmania heat-shock protein 70 gene (hsp70) regions, producing fragments ranging in size from 230-390 bp were developed and evaluated to determine their potential as a tool for the specific molecular diagnosis of cutaneous leishmaniasis (CL). A total of 70 Leishmania strains were analysed, including seven reference strains (RS) and 63 previously typed strains. Analysis of the RS indicated a specific region of 234 bp in the hsp70 gene as a valid target that was highly sensitive for detection of Leishmania species DNA with capacity of distinguishing all analyzed species, after polymerase chain reaction-restriction fragment length polymorfism (PCR-RFLP). This PCR assay was compared with other PCR targets used for the molecular diagnosis of leishmaniasis: hsp70 (1400-bp region), internal transcribed spacer (ITS)1 and glucose-6-phosphate dehydrogenase (G6pd). A good agreement among the methods was observed concerning the Leishmania species identification. Moreover, to evaluate the potential for molecular diagnosis, we compared the PCR targets hsp70-234 bp, ITS1, G6pd and mkDNA using a panel of 99 DNA samples from tissue fragments collected from patients with confirmed CL. Both PCR-hsp70-234 bp and PCR-ITS1 detected Leishmania DNA in more than 70% of the samples. However, using hsp70-234 bp PCR-RFLP, identification of all of the Leishmania species associated with CL in Brazil can be achieved employing a simpler and cheaper electrophoresis protocol.

Immunologic evaluation and validation of methods using synthetic peptides derived from Mycobacterium tuberculosis for the diagnosis of tuberculosis infection

The goal of this study was to demonstrate the usefulness of an enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of pulmonary tuberculosis (PTB) and extrapulmonary TB (EPTB). This assay used 20 amino acid-long, non-overlapped synthetic peptides that spanned the complete Mycobacterium tuberculosis ESAT-6 and Ag85A sequences. The validation cohort consisted of 1,102 individuals who were grouped into the following five diagnostic groups: 455 patients with PTB, 60 patients with EPTB, 40 individuals with non-EPTB, 33 individuals with leprosy and 514 healthy controls. For the PTB group, two ESAT-6 peptides (12033 and 12034) had the highest sensitivity levels of 96.9% and 96.2%, respectively, and an Ag85A-peptide (29878) was the most specific (97.4%) in the PTB groups. For the EPTB group, two Ag85A peptides (11005 and 11006) were observed to have a sensitivity of 98.3% and an Ag85A-peptide (29878) was also the most specific (96.4%). When combinations of peptides were used, such as 12033 and 12034 or 11005 and 11006, 99.5% and 100% sensitivities in the PTB and EPTB groups were observed, respectively. In conclusion, for a cohort that consists entirely of individuals from Venezuela, a multi-antigen immunoassay using highly sensitive ESAT-6 and Ag85A peptides alone and in combination could be used to more rapidly diagnose PTB and EPTB infection.

Oxidative stress enhances the expression of sulfur assimilation genes: preliminary insights on the Enterococcus faecalis iron-sulfur cluster machinery regulation

The Firmicutes bacteria participate extensively in virulence and pathological processes. Enterococcus faecalis is a commensal microorganism; however, it is also a pathogenic bacterium mainly associated with nosocomial infections in immunocompromised patients. Iron-sulfur [Fe-S] clusters are inorganic prosthetic groups involved in diverse biological processes, whose in vivo formation requires several specific protein machineries. Escherichia coli is one of the most frequently studied microorganisms regarding [Fe-S] cluster biogenesis and encodes the iron-sulfur cluster and sulfur assimilation systems. In Firmicutes species, a unique operon composed of the sufCDSUB genes is responsible for [Fe-S] cluster biogenesis. The aim of this study was to investigate the potential of the E. faecalis sufCDSUB system in the [Fe-S] cluster assembly using oxidative stress and iron depletion as adverse growth conditions. Quantitative real-time polymerase chain reaction demonstrated, for the first time, that Gram-positive bacteria possess an OxyR component responsive to oxidative stress conditions, as fully described for E. coli models. Likewise, strong expression of the sufCDSUB genes was observed in low concentrations of hydrogen peroxide, indicating that the lowest concentration of oxygen free radicals inside cells, known to be highly damaging to [Fe-S] clusters, is sufficient to trigger the transcriptional machinery for prompt replacement of [Fe-S] clusters.

Creation and validation of an instrument to identify nursing activities in pediatric wards: information for determining workload

The aim of this study was to develop and validate an instrument for identifying nursing activities performed in a pediatric ward and to provide a basis for defining the workload of these units. The instrument was developed by selecting the activities relevant to pediatric nursing from the Nursing Intervention Classification and then submitting them to a panel of judges for validation. The panel considered the selected activities relevant and representative of pediatric nursing practice. Now that representative activities for the nursing workload have been identified, we envision new studies to verify their usefulness in practice. Determining the amount of time each activity takes to perform will help to develop a system for measuring the workloads of nursing teams in pediatric wards.

Content validation of the dimensions constituting non-adherence to treatment of arterial hypertension

The objective of the study was to validate the content of the dimensions that constituted nonadherence to treatment of arterial systemic hypertension. It was a methodological study of content validation. Initially an integrative review was conducted that demonstrated four dimensions of nonadherence: person, disease/treatment, health service, and environment. Definitions of these dimensions were evaluated by 17 professionals, who were specialists in the area, including: nurses, pharmacists and physicians. The Content Validity Index was calculated for each dimension (IVCi) and the set of the dimensions (IVCt), and the binomial test was conducted. The results permitted the validation of the dimensions with an IVCt of 0.88, demonstrating reasonable systematic comprehension of the phenomena of nonadherence.

Content validation of the nursing diagnosis Nausea

This study aimed to evaluate the content validity of the nursing diagnosis of nausea in the immediate post-operative period, considering Fehring’s model. Descriptive study with 52 nurses experts who responded an instrument containing identification and validation of nausea diagnosis data. Most experts considered the domain 12 (Comfort), Class 1 (Physical Comfort) and the statement (Nausea) adequate to the diagnosis. Modifications were suggested in the current definition of this nursing diagnosis. Four defining characteristics were considered primary (reported nausea, increased salivation, aversion to food and vomiting sensation) and eight secondary (increased swallowing, sour taste in the mouth, pallor, tachycardia, diaphoresis, sensation of hot and cold, changes in blood pressure and pupil dilation). The total score for the diagnosis of nausea was 0.79. Reports of nausea, vomiting sensation, increased salivation and aversion to food are strong predictors of nursing diagnosis of nausea.

Development and validation of the Family Vulnerability Index to Disability and Dependence (FVI-DD)

This exploratory, descriptive, cross-sectional, and quantitative study aimed to develop and validate an index of family vulnerability to disability and dependence (FVI-DD). This study was adapted from the Family Development Index, with the addition of social and health indicators of disability and dependence. The instrument was applied to 248 families in the city of Sao Paulo, followed by exploratory factor analysis. Factor validation was performed using the concurrent and discriminant validity of the Lawton scale and Katz Index. The descriptive level adopted for the study was p < 0.05. The final vulnerability index comprised 50 questions classified into seven factors contemplating social and health dimensions, and this index exhibited good internal consistency (Cronbach’s alpha = 0.82). FVI-DD was validated using both the Lawton scale and Katz Index. We conclude that FVI-DD can accurately and reliably assess family vulnerability to disability and dependence.

Use of alcohol in the elderly: transcultural validation of the Michigan Alcoholism Screening Test – Geriatric Version (MAST-G)

Objective: To evaluate the internal consistency of the version of the Michigan Alcoholism Screening Test – Geriatric Version (MAST-G) instrument, translated and adapted for Brazil. Method: This was a descriptive, cross-sectional study. Data were collected through a demographic questionnaire, the ICD-10 and the MAST-G, following the steps of translation and cultural adaptation. One hundred eleven elderly in the city of São Carlos, SP, Brazil were interviewed. Results: The mean age of those interviewed was 70 years, with 45% men and 55% women, with the mean education of three years; 92% resided with family; 48% of the subjects consumed alcoholic beverages. The MAST-G presented a good level of reliability, with Cronbach’s α = 0.7873, and good levels of sensitivity and specificity with a cutoff score of five positive responses. Conclusion: The Brazilian version of the MAST-G presented internal consistency values similar to the original English version,showing it to be adequate for use in the national context.





Study of adaptation and validation of the Practice environment scale of the nursing work index for the portuguese reality

Objective: Testing the psychometric properties of the Portuguese version of the Practice Environment Scale of the Nursing Work Index. Method: A descriptive, analytical and cross-sectional study, for the cross-cultural adaptation and validation of the psychometric properties of the scale. The study participants were 236 nurses from two hospitals in the regions of Lisbon and Vale do Tejo. Results: The 0.92 Cronbach’s alpha was obtained for overall reliability and support of a five-dimension structure. Conclusion: The excellent quality of adjustment of analysis confirms the validity of the adapted version to hospital care settings, although there was no total coincidence of items in the five dimensions