The situation of chlorpyrifos in Mexico: a case study in environmental samples and aquatic organisms.

Chlorpyrifos (CPF) is one of the most commonly used organophosphate pesticides. Because CPF was described as a toxic compound without safe levels of exposure for children, certain countries in Latin America and the European Union have banned or restricted its use; however, in Mexico it is used very frequently. The aim of this study was to describe the current situation of CPF in Mexico, as well as its use, commercialization, and presence in soil, water, and aquatic organisms in an agricultural region of Mexico. Structured questionnaires were applied to pesticide retailers to determine the sales pattern of CPF (ethyl and methyl); in addition, monthly censuses were conducted with empty pesticide containers to assess the CPF pattern of use. Furthermore, samples of soil (48 samples), water (51 samples), and fish (31 samples) were collected, which were analyzed chromatographically. Descriptive statistics were performed. The results indicate that CPF was one of the most sold (3.82%) and employed OP (14.74%) during 2021. Only one soil sample was found above the CPF limit of quantification (LOQ); in contrast, all water samples had CPF levels above the LOQ (x̄ = 4614.2 ng/L of CPF). In the case of fish samples, 6.45% demonstrated the presence of methyl-CPF. In conclusion, the information obtained in this study indicates the need for constant monitoring in the area, since the presence of CPF in soil, water, and fish constitutes a threat to the health of wildlife and humans. Therefore, CPF should be banned in Mexico to avoid a serious neurocognitive health problem.

Temporal visitation patterns of points of interest in cities on a planetary scale: a network science and machine learning approach.

We aim to study the temporal patterns of activity in points of interest of cities around the world. In order to do so, we use the data provided by the online location-based social network Foursquare, where users make check-ins that indicate points of interest in the city. The data set comprises more than 90 million check-ins in 632 cities of 87 countries in 5 continents. We analyzed more than 11 million points of interest including all sorts of places: airports, restaurants, parks, hospitals, and many others. With this information, we obtained spatial and temporal patterns of activities for each city. We quantify similarities and differences of these patterns for all the cities involved and construct a network connecting pairs of cities. The links of this network indicate the similarity of temporal visitation patterns of points of interest between cities and is quantified with the Kullback-Leibler divergence between two distributions. Then, we obtained the community structure of this network and the geographic distribution of these communities worldwide. For comparison, we also use a Machine Learning algorithm-unsupervised agglomerative clustering-to obtain clusters or communities of cities with similar patterns. The main result is that both approaches give the same classification of five communities belonging to five different continents worldwide. This suggests that temporal patterns of activity can be universal, with some geographical, historical, and cultural variations, on a planetary scale.

Temephos, an organophosphate larvicide for residential use: a review of its toxicity.

Temephos (O,O,O',O'-tetramethyl O,O'-thiodi-p-phenylene bis(phosphorothioate)) is a larvicide belonging to the family of organophosphate pesticides used for the control of different vectors of diseases, such as dengue, Zika, chikungunya, and dracunculiasis. The aim of this review was to discuss the available published information about temephos toxicokinetics and toxicity in mammals. Temephos is quickly absorbed in the gastrointestinal tract, distributed to all organs, and then it accumulates mainly in adipose tissue. It is metabolized by S-oxidation, oxidative desulfuration, and hydrolysis reactions, with the possible participation of cytochrome P450 (CYP). Temephos is mainly eliminated by feces, whereas some of its metabolites are eliminated by urine. The World Health Organization classifies it as class III: slightly dangerous with a NOAEL (no-observed adverse effect level) of 2.3 mg/kg/day for up to 90 days in rats, based on brain acetylcholinesterase (AChE) inhibition. A LOAEL (lowest observable adverse effect level) of 100 mg/kg/day for up to 44 days in rats was proposed based on cholinergic symptoms. However, some studies have shown that temephos causes toxic effects in mammals. The inhibition of the enzyme acetylcholinesterase (AChE) is one of its main demonstrated effects; however, this larvicide has also shown genotoxic effects and some adverse effects on male reproduction and fertility, as well as liver damage, even at low doses. We performed an extensive review through several databases of the literature about temephos toxicokinetics, and we recommend to revisit current assessment of temephos with the new available data.

Organophosphorus pesticide exposure biomarkers in a Mexican population.

The organophosphate (OP) pesticides are neurotoxic compounds widely used around the world. Evaluation of OP exposure in human studies is important for enabling adequate data analyses and drawing accurate conclusions. The aim of this study was to analyze OP exposure biomarkers and their relationships in a Mexican population with different exposure levels. Dialkylphosphates (DAP) were determined through gas chromatography-mass spectrometry (GC-MSD); acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), arylesterase (AREase), basal paraoxonase 1 (PONase), and ß-glucuronidase activities were detected using spectrophotometric methods. The albumin content was determined in a certified clinical laboratory. The DMTP metabolite was found in the highest concentration, and a negative and significant correlation between DAP and cholinesterase activity was observed. Our results suggested that BuChE is a considerably more sensitive biomarker than AChE. In addition, ß-glucuronidase was positively correlated with albumin, BuChE, and PONase. In conclusion, our data strongly support the use of two or more biomarkers of exposure in human monitoring and the application of a strong and validated questionnaire.

Toxicokinetics of temephos after oral administration to adult male rats.

Temephos (Tem) is the larvicide of choice to control mosquito transmission of dengue, Zika, and chikungunya. The toxicokinetic and toxicological information of temephos is very limited. The aim of this work was to determine the toxicokinetics and dosimetry of temephos and its metabolites. Male Wistar rats were orally administered temephos (300 mg/kg) emulsified with saline solution and sacrificed over time after dosing. Temephos and its metabolites were analyzed in blood and tissues by high performance liquid chromatography-diode array detector. At least eleven metabolites were detected, including temephos-sulfoxide (Tem-SO), temephos-oxon (Tem-oxon), temephos-oxon-sulfoxide (Tem-oxon-SO), temephos-oxon-SO-monohydrolyzed (Tem-oxon-SO-OH), 4,4´-thiodiphenol, 4,4´-sulfinyldiphenol, and 4,4´-sulfonyldiphenol or bisphenol S (BPS). The mean blood concentrations of temephos were fitted to a one-compartment model for kinetic analysis. At 2 h, the peak was reached (t1/2 abs = 0.38 h), and only trace levels were detected at 36 h (t1/2 elim = 8.6 h). Temephos was detected in all tissues and preferentially accumulated in fat. Temephos-sulfone-monohydrolyzed (Tem-SO2-OH) blood levels remained constant until 36 h and gradually accumulated in the kidney. Tem-oxon was detected in the brain, liver, kidney, and fat. Clearance from the liver and kidney were 7.59 and 5.52 ml/min, respectively. These results indicate that temephos is well absorbed, extensively metabolized, widely distributed and preferentially stored in adipose tissue. It is biotransformed into reactive metabolites such as Tem-oxons, Tem-dioxons, and BPS. Tem-SO2-OH, the most abundant metabolite of temephos, could be used as an exposure biomarker for toxicokinetic modeling. These results could provide critical insight into the dosimetry and toxicity of temephos and its metabolites.

Human Biotransformation Pathway of Temephos Using an In Silico Approach.

Temephos is an organophosphorothioate (OPT) larvicide used for controlling vectors of diseases such as dengue, chikungunya, and Zika. OPTs require a metabolic activation mediated by cytochrome P540 (CYP) to cause toxic effects, such as acetylcholinesterase (AChE) activity inhibition. There is no information about temephos biotransformation in humans, and it is considered to have low toxicity in mammals. Recent studies have reported that temephos-oxidized derivatives cause AChE inhibition. The aim of this study was to propose the human biotransformation pathway of temephos using in silico tools. The metabolic pathway was proposed using the MetaUltra program of MultiCase software as well as the Way2Drug and Xenosite web servers. The results show the following three essential reactions of phase I metabolism: (1) S-oxidation, (2) oxidative desulfurization, and (3) dephosphorylation, as well as the formation of 19 possible intermediary metabolites. Temephos dephosphorylation is the most likely reaction, and it enables phase II metabolism for glucuronidation to be excreted. However, the CYP-dependent metabolism showed that temephos oxon can be formed, which could lead to toxic effects in mammals. CYP2B6, 2C9, and 2C19 are the main isoforms involved in temephos metabolism, and CYP3A4 and 2D6 have minor contributions. According to computational predictions, the highest probability of temephos metabolism is dephosphorylation and phase II reactions that do not produce cholinergic toxic effects; nonetheless, the participation of CYPs is highly possible if the primary reaction is depleted.

In vitro inhibition of human red blood cell acetylcholinesterase (AChE) by temephos-oxidized products.

Temephos (Tem) is an organophosphorus pesticide widely used to kill and prevent the growth of the main vectors for the transmission of dengue, zika, and chikungunya viruses. In chlorinated water, Tem is oxidized to its dioxon-sulfoxide (Tem-dox-SO), dioxon-sulfone (Tem-dox-SO2), and sulfoxide (Tem-SO) derivatives; however, these compounds are not commercially available to be used as standards and in toxicological studies. In the present study, we synthesized and characterized the Tem-oxidation products and the compound 4,4'-sulfinyldiphenol. These compounds were obtained by a simple reaction between Tem or 4,4'-thiodiphenol with sodium hypochlorite or potassium periodate, and were characterized by IR, NMR, and UPLC-HRESIMS. The in vitro evaluation of inhibitory potency of Tem-oxidized products on human red blood cell acetylcholinesterase (RBC AChE) showed that Tem-dox-SO2 was the most potent inhibitor of human RBC AChE, and its effect was more pronounced than that observed for ethyl-paraoxon, a potent typical inhibitor of AChE. An HPLC-DAD method for the analysis of metabolic products of Tem was developed, which may be useful for monitoring in biological and environmental samples. The ability of Tem-oxidized metabolites to inhibit human RBC AChE suggests that the addition of Tem to chlorinated drinking water could result in an increase in the risk of RBC AChE inhibition after exposure.

Incidencia de la insatisfacción laboral en la eficiencia de la gestión. Caso Clínica Estomatológica / Incidence of the occupational dissatisfaction in the efficiency of management. Case Dental Clinic

Introducción: la calidad en la gestión de los servicios asistenciales, es una exigencia que produce beneficios tanto para la población como para las instituciones de salud, máxime en Cuba, donde "Los servicios de salud son gratuitos, pero cuestan". Los costos de calidad son indicadores de eficiencia, particularmente en las partidas asociadas a fallos que evalúan los recursos malgastados por una deficiente gestión y sobre lo cual deberán enfocarse las acciones para la mejora. Objetivo: identificar los costos por fallos, en estrecha relación con el análisis de sus causas y la satisfacción de los trabajadores. Materiales y métodos: se realizó un estudio descriptivo. La metódica radicó en la investigación de campo en base a encuestas aplicadas a los trabajadores, revisión de documentos, evaluación de partidas de costos por extensión del sistema contable o estimación, según el caso, así como el análisis causal desarrollado por un grupo de expertos de la organización, con representación de las diferentes áreas de la clínica objeto de estudio. Resultados: se evalúan monetariamente fallos incurridos durante el año 2014, ascendiendo a $ 12260,49, los mayores montos estuvieron asociados a reelaboraciones y desperdicios. El análisis causal mostró una fuerte incidencia de los trabajadores en la ocurrencia de dichas ineficiencias, predominando las negligencias. La insatisfacción de los trabajadores, fue de una media general de 2,94 (por debajo de 3), lo que se puede interpretar como que estos reciben menos de lo que esperan, esencialmente, en cuanto a salario, condiciones laborales y participación en la toma de decisiones. Conclusiones: se establecen los montos de los costos asociados a fallos en la gestión de los servicios de la Clínica Estomatológica III Congreso del PCC, en línea con el análisis de la satisfacción de los trabajadores como elemento causal fundamental que incide en la calidad de los servicios en dicha organización, la cual debe establecer plan de mejoras en su gestión (AU).

Introduction: the quality of management in health care services is an exigency producing benefits both for the population and for health institutions, especially in Cuba, where "health services are free, but they cost." The quality costs are indicators of efficiency, particularly in the items associated to failures assessing resources misspent for a deficient management, and on which the actions should be focused for getting improvement. Objective: to identify the costs by failures, in tight relation with the analysis of their causes and workers´ satisfaction. Materials and methods: a descriptive study was carried out. Methodologically, it was a field research on the bases of surveys applied to workers, documental reviewing, and evaluation of cost items by extension of the accounting system or estimation, according to the case, and also the causal analyses performed by an expert group of the organization, with representatives of the different areas of the clinic being studied. Results: the failures that occurred during 2014 are monetarily evaluated, coming to $ 12 260.49. The highest amounts were associated to re-elaborations and wastes. The causal analysis showed a strong incidence of the workers in the occurrence of those inefficiencies, predominating negligence. The workers´ dissatisfaction was in general average 2.94 (under 3), what may be interpreted like if they receive less than they expect, essentially as for salary, working conditions and participation in decision-making. Conclusions: the amount of the cost associated to failures in the management of the services in the Dental Clinic "III Congreso del PCC" is established, aligned with the analysis of the workers´ satisfaction as main causal element striking in the quality of the services in that institution; they should elaborate and carried out a plan for the improvement of their management (AU).

Correlación ecográfica, citológica y mamográfica en el diagnóstico del cáncer de mama / Mammographic, cytological, and ecographic correlation in the diagnosis of breast cancer

FUNDAMENTO: el cáncer de mama es la segunda causa de muerte por cáncer y su diagnóstico se basa en la obtención de los factores de riesgo, los hallazgos al examen físico, las pruebas de imágenes y el examen microscópico. OBJETIVO: establecer la correlación ecográfica, citológica y mamográfica en el diagnóstico del cáncer de mama. Métodos: se realizó un estudio de serie de casos, descriptivo, correlacional y prospectivo en un universo de 94 pacientes con diagnóstico de algún tipo de cáncer de mamas atendidas en el Hospital Provincial Universitario Celia Sánchez Manduley, Manzanillo, Granma, desde enero de 2013 a junio de 2014. Los datos fueron obtenidos de las historias clínicas determinándose los hallazgos ecográficos, citológicos, mamográficos y la correlación entre ellos con la biopsia posoperatoria por inclusión en parafina en el establecimiento del diagnóstico definitivo. RESULTADOS: Predominaron los hallazgos ecográficos de una masa sólida hipoecoica de contornos mal definidos e irregulares y mamográficos de una imagen radiopaca de contornos mal definidos, irregulares o espiculados. La correlación entre las pruebas diagnósticas fue de 0,83. CONCLUSIONES: los resultados del diagnóstico ecográfico, citológico y mamográfico en el cáncer de mama eleva la posibilidad de detección de esta enfermedad a valores casi absolutos al tener un coeficiente de correlación elevado.

BACKGROUND: breast cancer is the second cause of death due to this condition and its diagnosis is based on the obtaining of risks factors, finds in the physical examination, imaging tests, and the microscopic test. OBJECTIVE: to establish the mammographic, cytological, and ecographic correlation in the diagnosis of breast cancer. Methods: a prospective, correlation, descriptive, case series study was conducted in a universe of 94 patients with the diagnosis of any type of breast cancer treated in the Celia Sánchez Manduley Provincial Teaching Hospital, Manzanillo, Granma, from January, 2013 to June, 2014. The data were obtained from medical histories. Ecographic, cytological, mammographic finds and their correlation with the postoperative biopsy by paraffin inclusion were determined, establishing the definite diagnosis. RESULTS: ecographic finds of a hypoechoic solid mass of irregular and non-defined margins predominated, as well as mammographic finds of a radiopaque image of spicular, irregular, non-defined margins. The correlation among the diagnostic tests was of 0, 83. CONCLUSIONS: the results of the ecographic, cytological and mammographic diagnosis in breast cancer increases the possibility of detecting the disease to almost-absolute values since there is a high correlation coefficient.

Eficiente administración sanitaria? Caso clínica estomatológica / Efficient sanitary administration? The Stomatologic Clinic Case

La administración en las instituciones de salud es un tema importante para el logro de la satisfacción de los pacientes y familiares, a la par de la correcta utilización de los recursos disponibles. El sistema de salud en Cuba es presupuestado, y por ello, una gestión eficiente es vital para distribuir los recursos en función de los mejores resultados. Un importante indicador a considerar en este tema lo constituyen los costos de calidad. Dentro del sistema nacional de salud, las clínicas estomatológicas son organizaciones donde resulta muy novedoso el tema de mejoramiento continuo de su gestión a partir de los costos de calidad. En el presente trabajo se realizó una evaluación de los costos de calidad en la Clínica Estomatológica Docente III Congreso del PCC, lo cual constituyó la base del programa de mejoras. El costo total de calidad fue de 22 394.15 pesos en el año 2011, siendo el 62,69 por ciento por fallos relacionados esencialmente a reelaboraciones, desperdicios, paralización parcial por poco instrumental, entre otras causas que fueron la base del programa de mejora.

The administration of health care institutions is an important theme for achieving the patients and relatives satisfaction, and the right usage of the available resources at the same time. Health Care System in Cuba is budgeted and for that, an efficient management is vital in distributing the resources for better results. Quality costs are an important indicator to consider in this theme. Inside the national Health Care System, stomatologic clinics are organizations where it is fashionable the theme of the continuous management improvement on the basis of the quality costs. In the current work we carried out an evaluation of the quality costs at the Teaching Stomatologic Clinic III Congreso del Partido, took as the basis of the improvement program. The total quality cost was 22 394.15 pesos in 2011. 62,69 percent was caused by mistakes essentially related with re-elaboration, wastes, partial paralyzing because of few instrumental, among other causes that were the base of the improvement program.

Unidad de cirugía ambulatoria Hospital Universitario Dr. Angel Larralde / Unit of ambulatory surgery in the

Se presenta la experiencia obtenida de la aplicación de un ensayo preliminar de una Unidad de Cirugía Ambulatoria en el Hospital Universitario Angel Larralde del Edo. Carabobo, Venezuela, en 1996. Con la implementación de un organigrama administrativo-asistencial de una Unidad de Cirugía Ambulatoria adaptado a la Institución Hospitalaria. Se aplicó a manera de ensayo el anteproyecto por un período no menor de 30 sesiones a fin de obtener resultados preliminares que facilitaran la adaptación y modificación reglamentaria de un sistema definitivo. Se intervinieron un total de 169 pacientes en un total de 36 sesiones quirúrgicas, de las cuales 101 se realizaron en un quirófano de Cirugía menor sin la asistencia de Anestesiólogo y 68 fueron realizadas en un quirófano de Cirug¡a Mayor con un Anestesiólogo asignado. Con un promedio de 4 y 5 casos por sesión respectivamente. Se aprecia que la patolog¡a herniaria encabeza la lista de frecuencia. La Estancia Hospitalaria se redujo a un promedio entre 2 a 4 horas por procedimientos ambulatorios. La Unidad de Cirugía Ambulatoria del H.U.A.L. promete ser una alternativa eficiente, competitiva y con criterios de avanzada para hacerla extensiva a otras subespecialidades quirúrgicas