Examinando por Autor "Rueda-Torres, Lenin"

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Acceso abierto
Leadcare II Comparison with Graphite Furnace Atomic Absorption Spectrophotometry for Blood Lead Measurement in Peruvian Highlands
(Springer, 2022-05-30) Rosales-Rimache, Jaime; Chavez-Ruiz, Manuel; Inolopú-Cucche, Jorge; Rabanal-Sanchez, Jhonatan; Rueda-Torres, Lenin; Sanchez-Holguin, Gloria
“Peru is one of the countries with the highest lead contamination in the world. Biological monitoring has limitations due to the shortage of laboratories with validated methodologies for the measurement of blood lead, and it is necessary to use alternative methods for its measurement in high-altitude cities. We aimed to compare the blood lead levels (BLL) measured by the LeadCare II (LC) method and Graphite Furnace Atomic Absorption Spectrometry (GFAAS). We measured the BLL of 108 children from the city of La Oroya. The mean and median BLL for GF-AAS were 10.77 ± 4.18 and 10.44 lg/dL, respectively; for the LC method, the mean was 11.71 ± 4.28 and the median was 11.60 lg/dL. We found a positive linear correlation (Rho = 0.923) between both methods. Notwithstanding, the Wilcoxon test suggests a significant difference between both methods (q = 0.000). In addition, the Bland–Altman analysis indicates that there is a positive bias (0.94) in the LC method, and this method tends to overestimate the BLL. Likewise, we performed a generalized linear model to evaluate the influence of age and hemoglobin on BLL. We found that age and hemoglobin had a significant influence on BLL measured by the LC method. Finally, we used two nonparametric linear regression methods (Deming and PassingBablok regression) to compare the LC method with the GFAAS. We found that these methods differ by at least a constant amount, and there would be a proportional difference between both. Although in general there is a positive linear correlation, the results of both methods differ significantly. Therefore, its use in cities located at high altitudes (higher than 2440 m.a.s.l.) would not be recommended.“
Acceso abierto
Leadcare II Comparison with Graphite Furnace AtomicAbsorption Spectrophotometry for Blood Lead Measurementin Peruvian Highlands
(Springer, 2022-05-30) Rosales-Rimache, Jaime; Chavez-Ruiz, Manuel; Inolopú-Cucche, Jorge; Rabanal-Sanchez, Jhonatan; Rueda-Torres, Lenin; Sanchez-Holguin, Gloria
Peru is one of the countries with the highest leadcontamination in the world. Biological monitoring has lim-itations due to the shortage of laboratories with validatedmethodologies for the measurement of blood lead, and it isnecessary to use alternative methods for its measurement inhigh-altitude cities. We aimed to compare the blood leadlevels (BLL) measured by the LeadCare II (LC) method andGraphite Furnace Atomic Absorption Spectrometry (GF-AAS). We measured the BLL of 108 children from the city ofLa Oroya. The mean and median BLL for GF-AAS were10.77±4.18 and 10.44lg/dL, respectively; for the LCmethod, the mean was 11.71±4.28 and the median was11.60lg/dL. We found a positive linear correlation(Rho = 0.923) between both methods. Notwithstanding, theWilcoxon test suggests a significant difference between bothmethods (q= 0.000). In addition, the Bland–Altmananalysis indicates that there is a positive bias (0.94) in the LCmethod, and this method tends to overestimate the BLL.Likewise, we performed a generalized linear model toevaluate the influence of age and hemoglobin on BLL. Wefound that age and hemoglobin had a significant influence onBLL measured by the LC method. Finally, we used two non-parametric linear regression methods (Deming and Passing-Bablok regression) to compare the LC method with the GF-AAS. We found that these methods differ by at least a con-stant amount, and there would be a proportional differencebetween both. Although in general there is a positive linearcorrelation, the results of both methods differ significantly.Therefore, its use in cities located at high altitudes (higherthan 2440 m.a.s.l.) would not be recommended.
Acceso abierto
Leadcare II Comparison with Graphite Furnace AtomicAbsorption Spectrophotometry for Blood Lead Measurementin Peruvian Highlands
(Springer, 2022-05-22) Rosales-Rimach, Jaime; Chavez-Ruiz, Manuel; Inolopú-Cucche, Jorge; Rabanal-Sanchez, Jhonatan; Rueda-Torres, Lenin; Sanchez-Holguin, Gloria S
Peru is one of the countries with the highest leadcontamination in the world. Biological monitoring has lim-itations due to the shortage of laboratories with validatedmethodologies for the measurement of blood lead, and it isnecessary to use alternative methods for its measurement inhigh-altitude cities. We aimed to compare the blood leadlevels (BLL) measured by the LeadCare II (LC) method andGraphite Furnace Atomic Absorption Spectrometry (GF-AAS). We measured the BLL of 108 children from the city ofLa Oroya. The mean and median BLL for GF-AAS were10.77±4.18 and 10.44lg/dL, respectively; for the LCmethod, the mean was 11.71±4.28 and the median was11.60lg/dL. We found a positive linear correlation(Rho = 0.923) between both methods. Notwithstanding, theWilcoxon test suggests a significant difference between bothmethods (q= 0.000). In addition, the Bland–Altmananalysis indicates that there is a positive bias (0.94) in the LCmethod, and this method tends to overestimate the BLL.Likewise, we performed a generalized linear model toevaluate the influence of age and hemoglobin on BLL. Wefound that age and hemoglobin had a significant influence onBLL measured by the LC method. Finally, we used two non-parametric linear regression methods (Deming and Passing-Bablok regression) to compare the LC method with the GF-AAS. We found that these methods differ by at least a con-stant amount, and there would be a proportional differencebetween both. Although in general there is a positive linearcorrelation, the results of both methods differ significantly.Therefore, its use in cities located at high altitudes (higherthan 2440 m.a.s.l.) would not be recommended.
Acceso abierto
Performance of Bleach Method Sputum Smear Microscopy for the Diagnosis of Tuberculosis in a Highly Endemic District in Lima, Peru
(MDPI, 2022-12-22) Rosales-Rimache, Jaime; Nunayalle-Vargas, Magda; Rueda-Torres, Lenin; Inolopú-Cucche, Jorge
Background: Sputum smear microscopy (SSM) is a screening test used to diagnose tuberculosis (TB); however, its performance and sensitivity are relatively low, which can lead to false negatives. We designed a cross-sectional study to estimate the performance of SSM that includes a pretreatment based on sputum digestion with bleach (sodium hypochlorite) for the diagnosis of TB. Methods: We evaluated 73 sputum samples from patients with a diagnosis of TB confirmed by the Xpert MTB/RIF test and 114 samples from patients without TB. We performed sputum digestion using a 5% sodium hypochlorite solution, centrifuged at 2000 rpm for 15 min. We prepared smears for direct and bleach-treated SSM and used Ziehl–Neelsen staining. Results: The bleach-treated SSM obtained absolute identification of the cases of TB confirmed by the Xpert test, compared to 95.9% identified by the direct smear method (without bleach treatment). We also found a significant increase (p < 0.001) in the recovery of acid-fast bacilli (AFB) obtained by the bleach-treated SSM (293.8 ± 215.1 AFB) compared to the direct SSM method (222.9 ± 195.5 AFB). The AUC of the bleach-treated SSM and direct SSM was 100% and 96.6%, respectively. Conclusion: The bleach-treated SSM performs better than the direct SSM in identifying AFB and increasing the bacillary count in the sputum samples.
Acceso abierto
Performance of Bleach Method Sputum Smear Microscopy for the Diagnosis of Tuberculosis in a Highly Endemic District in Lima, Peru
(MDPI, 2022-12-22) Rosales-Rimache, Jaime; Nunayalle-Vargas, Magda; Rueda-Torres, Lenin; Inolopú-Cucche, Jorge
Background: Sputum smear microscopy (SSM) is a screening test used to diagnose tuberculosis (TB); however, its performance and sensitivity are relatively low, which can lead to false negatives. We designed a cross-sectional study to estimate the performance of SSM that includes a pretreatment based on sputum digestion with bleach (sodium hypochlorite) for the diagnosis of TB. Methods: We evaluated 73 sputum samples from patients with a diagnosis of TB confirmed by the Xpert MTB/RIF test and 114 samples from patients without TB. We performed sputum digestion using a 5% sodium hypochlorite solution, centrifuged at 2000 rpm for 15 min. We prepared smears for direct and bleach-treated SSM and used Ziehl–Neelsen staining. Results: The bleach-treated SSM obtained absolute identification of the cases of TB confirmed by the Xpert test, compared to 95.9% identified by the direct smear method (without bleach treatment). We also found a significant increase (p < 0.001) in the recovery of acid-fast bacilli (AFB) obtained by the bleach-treated SSM (293.8 ± 215.1 AFB) compared to the direct SSM method (222.9 ± 195.5 AFB). The AUC of the bleach-treated SSM and direct SSM was 100% and 96.6%, respectively. Conclusion: The bleach-treated SSM performs better than the direct SSM in identifying AFB and increasing the bacillary count in the sputum samples.