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1.
BMC Public Health ; 24(1): 1117, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654278

RESUMO

BACKGROUND: Despite nearly a quarter of Venezuelans remaining unvaccinated against coronavirus disease 2019 (COVID-19), the factors contributing to vaccine hesitancy in the country have not been thoroughly investigated. METHODS: A cross-sectional study was conducted from October 15th to 30th, 2022, using a knowledge, attitudes, and practices (KAP) survey to identify factors associated with COVID-19 vaccine hesitancy. RESULTS: The study analyzed data from 1,930 participants from all 24 states of Venezuela. The majority (93.4%) were vaccinated. The mean age was 40 years, predominantly female (67.3%), and held a university degree (70.6%). The mean KAP score was significantly higher among vaccinated individuals compared to unvaccinated ones (7.79 vs. 3.94 points for knowledge, 40 vs. 24 points for attitudes, and 16 vs. 10 points for practices, all p < 0.001). Increases in the scores for KAP were associated with increased odds of being vaccinated (84.6%, 25.6%, and 33% respectively for each one-point increase, all p < 0.001). Certain demographic factors such as marital status, occupation, religious beliefs, monthly income, and location influence COVID-19 vaccine knowledge. Higher income and certain occupations decrease the odds of low knowledge, while residing in specific states increases it. Attitudes towards the COVID-19 vaccine are influenced by age, health status, vaccination status, and location. Higher income and absence of certain health conditions decrease the odds of negative attitudes. Lastly, age, occupation, monthly income, and location affect vaccine practices. Advanced age and higher income decrease the odds of inappropriate practices, while residing in La Guaira state increases them. CONCLUSION: Factors such as age, education level, occupation, monthly income, and location were found to be associated with knowledge and attitudes towards COVID-19 vaccine among the surveyed Venezuelans.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Conhecimentos, Atitudes e Prática em Saúde , Hesitação Vacinal , Humanos , Venezuela , Feminino , Masculino , Adulto , Hesitação Vacinal/estatística & dados numéricos , Hesitação Vacinal/psicologia , Estudos Transversais , Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , COVID-19/psicologia , Pessoa de Meia-Idade , Adulto Jovem , Inquéritos e Questionários , Adolescente , Idoso
2.
BMC Infect Dis ; 24(1): 87, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225550

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has disrupted multiple health services, including human immunodeficiency virus (HIV) testing, care, and treatment services, jeopardizing the achievement of the Joint United Nations Programme on HIV/AIDS 90-90-90 global target. While there are limited studies assessing the impact of the COVID-19 pandemic on people living with HIV (PLHIV) in Latin America, there are none, to our knowledge, in Venezuela. This study aims to assess the impact of the COVID-19 pandemic among PLHIV seen at the outpatient clinic of a reference hospital in Venezuela. METHODS: We conducted a cross-sectional study among PLHIV aged 18 years and over seen at the Infectious Diseases Department of the University Hospital of Caracas, Venezuela between March 2021 and February 2022. RESULTS: A total of 238 PLHIV were included in the study. The median age was 43 (IQR 31-55) years, and the majority were male (68.9%). Most patients (88.2%, n = 210) came for routine check-ups, while 28 (11.3%) were newly diagnosed. The majority of patients (96.1%) were on antiretroviral therapy (ART), but only 67.8% had a viral load test, with almost all (95.6%) being undetectable. Among those who attended regular appointments, 11.9% reported missing at least one medical consultation, and 3.3% reported an interruption in their ART refill. More than half of the patients (55.5%) had received at least one dose of the COVID-19 vaccine, while the rest expressed hesitancy to get vaccinated. Most patients with COVID-19 vaccine hesitancy were male (65.1%), younger than 44 years (57.5%), employed (47.2%), and had been diagnosed with HIV for less than one year (33%). However, no statistically significant differences were found between vaccinated patients and those with COVID-19 vaccine hesitancy. Older age was a risk factor for missing consultations, while not having an alcoholic habit was identified as a protective factor against missing consultations. CONCLUSION: This study found that the COVID-19 pandemic had a limited impact on adherence to medical consultations and interruptions in ART among PLHIV seen at the University Hospital of Caracas, Venezuela.


Assuntos
COVID-19 , Infecções por HIV , Humanos , Masculino , Feminino , Adolescente , Adulto , HIV , COVID-19/epidemiologia , Pandemias , Estudos Transversais , Vacinas contra COVID-19/uso terapêutico , Venezuela/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia
3.
BMC Infect Dis ; 23(1): 877, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097988

RESUMO

BACKGROUND: Persistent headache is a frequent symptom after coronavirus disease 2019 (COVID-19) and there is currently limited knowledge about its clinical spectrum and predisposing factors. A subset of patients may be experiencing new daily persistent headache (NDPH) after COVID-19, which is among the most treatment-refractory primary headache syndromes. METHODS: We conducted a cross-sectional study in Latin America to characterize individuals with persistent headache after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and to identify factors associated with NDPH. Participants over 18 years old who tested positive for SARS-CoV-2 infection and reported persistent headache among their symptoms completed an online survey that included demographics, past medical history, persistent headache clinical characteristics, and COVID-19 vaccination status. Based on participants' responses, NDPH diagnostic criteria were used to group participants into NDPH and non-NDPH groups. Participant data was summarized by descriptive statistics. Student's t and Mann-Whitney U tests were used according to the distribution of quantitative variables. For categorical variables, Pearson's chi-square and Fisher's exact tests were used according to the size of expected frequencies. Binomial logistic regression using the backward stepwise selection method was performed to identify factors associated with NDPH. RESULTS: Four hundred and twenty-one participants from 11 Latin American countries met the inclusion criteria. One in four participants met the NDPH diagnostic criteria. The mean age was 40 years, with most participants being female (82%). Over 90% of the participants reported having had mild/moderate COVID-19. Most participants had a history of headache before developing COVID-19 (58%), mainly migraine type (32%). The most predominant clinical characteristics in the NDPH group were occipital location, severe/unbearable intensity, burning character, and radiating pain (p < 0.05). A higher proportion of anxiety symptoms, sleep problems, myalgia, mental fog, paresthesia, nausea, sweating of the face or forehead, and ageusia or hypogeusia as concomitant symptoms were reported in participants with NDPH (p < 0.05). Palpebral edema as a concomitant symptom during the acute phase of COVID-19, occipital location, and burning character of the headache were risk factors associated with NDPH. CONCLUSION: This is the first study in Latin America that explored the clinical spectrum of NDPH after SARS-CoV-2 infection and its associated factors. Clinical evaluation of COVID-19 patients presenting with persistent headache should take into consideration NDPH.


Assuntos
COVID-19 , Transtornos da Cefaleia , Humanos , Feminino , Adulto , Adolescente , Masculino , COVID-19/complicações , COVID-19/epidemiologia , Estudos Transversais , América Latina/epidemiologia , SARS-CoV-2 , Vacinas contra COVID-19 , Transtornos da Cefaleia/diagnóstico , Transtornos da Cefaleia/etiologia , Cefaleia/epidemiologia , Cefaleia/etiologia
4.
Front Chem ; 11: 1233889, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37693168

RESUMO

Deep eutectic solvents (DES) formed using choline chloride (ChCl), p-toluenesulfonic acid (pTSA) of stoichiometry ChCl: pTSA (1:1) and (1:2), and its ternary eutectic mixtures with phosphoric acid (PA) 85% as an additive (ChCl: pTSA: PA) were evaluated for cellulose nanocrystal (CNC) isolation. Initially, the hydrolytic efficiency to produce CNC of each DES was compared before and after adding phosphoric acid by Hammett acidity parameters and the Gutmann acceptor number. Moreover, different DES molar ratios and reaction time were studied at 80°C for CNC optimization. The nanomaterial characteristics were analyzed by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The ternary eutectic mixture ChCl: pTSA: PA molar ratio (1:1:1.35) was chosen as a suitable recyclable ternary system at the laboratory scale. A CNC yield of about 80% was obtained from the hydrolysis of commercial cellulose in five cycles of recovery, but it dropped to 35% in pre-pilot scaling. However, no variation in the average size of the resulting CNC was observed (132 ± 50 nm x 23 ± 4 nm), which presented high thermal stability (Tmax 362°C) and high crystallinity of about 80% after 3 h of reaction time.

5.
Malar J ; 22(1): 11, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36611189

RESUMO

BACKGROUND: Malaria-endemic areas are not spared from the impact of coronavirus disease 2019 (COVID-19), leading to co-infection scenarios where overlapping symptoms impose serious diagnostic challenges. Current knowledge on Plasmodium spp. and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) co-infection in pregnant women remains limited, especially in Latin America, where Plasmodium vivax infection is highly prevalent. METHODS: This is a case series of five pregnant women with P. vivax and SARS-CoV-2 co-infection hospitalized in two main malaria referral centers of the Capital District and Bolivar state, Venezuela between March 13, 2020 and December 31, 2021. RESULTS: Clinical and laboratory data from five pregnant women with a mean age of 22 years were analyzed; three of them were in the third trimester of pregnancy. Comorbidities included obesity in two cases, hypertension in one, and asthma in one. Three out of five patients had severe to critical COVID-19 disease. Dry cough, fever, chills, and headache were the most frequent symptoms reported. Laboratory analyses showed elevated aspartate/alanine aminotransferase and creatinine levels, thrombocytopenia, and severe anemia as the most relevant abnormalities. The mean period between symptom onset and a positive molecular test for SARS-CoV-2 infection or positive microscopy for Plasmodium spp. was 4.8 ± 2.5 days and 2.8 ± 1.6 days, respectively. The mean hospital stay was 5.4 ± 7 days. Three women recovered and were discharged from the hospital. Two women died, one from cerebral malaria and one from respiratory failure. Three adverse fetal outcomes were registered, two miscarriages and one stillbirth. CONCLUSION: This study documented a predominance of severe/critical COVID-19 disease and a high proportion of adverse maternal-fetal outcomes among pregnant women with malaria and COVID-19 co-infection. More comprehensive prospective cohort studies are warranted to explore the risk factors, management challenges, and clinical outcomes of pregnant women with this co-infection.


Assuntos
Aborto Espontâneo , COVID-19 , Coinfecção , Malária Vivax , Malária , Complicações Infecciosas na Gravidez , Feminino , Humanos , Gravidez , Adulto Jovem , Coinfecção/diagnóstico , Coinfecção/epidemiologia , COVID-19/diagnóstico , COVID-19/epidemiologia , Malária Vivax/diagnóstico , Malária Vivax/epidemiologia , Plasmodium vivax , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/epidemiologia , Gestantes , Estudos Prospectivos , SARS-CoV-2 , Venezuela/epidemiologia
6.
BMC Pregnancy Childbirth ; 22(1): 905, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36471262

RESUMO

BACKGROUND: In low- and middle-income countries, pregnant women and newborns are more vulnerable to adverse outcomes from coronavirus disease 2019 (COVID-19). However, in Venezuela, there are no integrated data in a national surveillance system to identify the clinical-epidemiological characteristics and maternal-foetal outcomes of pregnant women hospitalised with COVID-19. METHODS: A retrospective study was conducted among Venezuelan pregnant women hospitalised with COVID-19 seen at the "Ruiz y Páez" University Hospital Complex and the San Cristobal Central Hospital between June 2020 and September 2021. Information was obtained from physical and digitised clinical records using a purpose-designed proforma to collect epidemiological, clinical, paraclinical, treatment, obstetric and perinatal complications, and maternal-foetal outcomes data. RESULTS: A total of 80 pregnant women with confirmed severe acute respiratory syndrome coronavirus 2 infection were seen within the study period, 59 (73.8%) survived and 21 (26.2%) died. The median (interquartile range) age was 29 (23-33) years, the majority being in the third trimester of pregnancy (81.2%; n = 65). Interestingly, four (5%) pregnant women were co-infected with malaria by Plasmodium vivax and three (3.8%) with syphilis. The most frequent symptoms were fever (75%; n = 60), dry cough (68.8%; n = 55), dyspnoea (55%; n = 44), and headache (53.8%; n = 43). The most frequent maternal complications were anaemia (51.5%; n = 66) and hypertensive disorders of pregnancy (17.5%; n = 14). The most frequent perinatal complications were preterm delivery (39.2%; n = 20/51) and oligohydramnios (31.3%; n = 25). A total of 29 (36.3%) adverse foetal outcomes were documented, 21 stillbirth and eight abortions. CONCLUSION: This is the first study to describe the clinical-epidemiological behaviour of COVID-19 in hospitalised Venezuelan pregnant women. Anaemia, hypertensive disorders of pregnancy, oligohydramnios, and low birth weight were the most frequent maternal-foetal complications in this population of pregnant women.


Assuntos
Anemia , COVID-19 , Hipertensão Induzida pela Gravidez , Oligo-Hidrâmnio , Complicações Infecciosas na Gravidez , Nascimento Prematuro , Recém-Nascido , Feminino , Gravidez , Humanos , Adulto , COVID-19/epidemiologia , Estudos Retrospectivos , Complicações Infecciosas na Gravidez/epidemiologia , Gestantes , Venezuela/epidemiologia , Nascimento Prematuro/epidemiologia , Natimorto/epidemiologia , Anemia/epidemiologia , Resultado da Gravidez/epidemiologia
8.
Int J Biol Macromol ; 211: 490-498, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35569683

RESUMO

Solutions of a pure organic solvent acidified with 1% sulfuric acid, and some of their aqueous mixtures were used for lignin extraction in the Pinus radiata sawdust delignification. Organic acid solvents including acetic, lactic and citric acids as well as non-acidic compounds such as γ-valerolactone, 2-methyltetrahydrofuran, glycerol and ethylene glycol were studied. Crude lignin extractions yields (%) ranging between ca. 5-50% were obtained, from which ethylene glycol (33%), γ-valerolactone (48%) and propylene carbonate (52%) showed the greatest effectiveness. The effect of added water on the lignin extraction was investigated in mixtures of an organic solvent with a variable water content (75%w/w, 50% w/w, 25%w/w and 10% w/w) where it was observed that the yield of extraction decreased with the increased water content. Moreover, the purity of extracted lignins were analyzed by spectroscopic methods (UV and IR). Kamlet-Taft solvent polarity parameters, were determined with the solvatochromic probes 4-nitroaniline, N,N-diethyl-4-nitroaniline, Nile Red and 6-propionyl-2-N,N-dimethylaminonaphthalene (PRODAN), and then correlated to lignin extraction yields to explain the influence of the solute-solvent interactions on biomass delignification. A reasonable correlation was found between the medium polarizability-dipolarity π* and the effectiveness of the solvent mixture on the extraction of lignin wood.


Assuntos
Lignina , Madeira , Etilenoglicol , Lignina/química , Solventes/química , Água/química , Madeira/química
9.
BMC Rheumatol ; 6(1): 2, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983688

RESUMO

BACKGROUND: We have here assessed the impact of demographic, clinical, and treatment compliance characteristics on health-related quality of life (HRQoL) of Venezuelan patients with systemic lupus erythematosus (SLE). We have used a disease-specific questionnaire, the Lupus Quality of Life (LupusQoL), validated in our patient population, to measure HRQoL. METHODS: A cross-sectional study was conducted among 100 patients with SLE from outpatient clinics. Patients completed a form with demographic, clinical, and treatment compliance data, and the LupusQoL questionnaire. HRQoL was classified as better or worse according to previously established cut-off points for this patient population. Spearman's r test was used to determine the correlations between age, years of education, disease duration, SLEDAI, and SLICC-DI with the eight domains of the LupusQoL. Mann-Whitney U test was used to compare the HRQoL between the two groups of patients according to treatment compliance. Binomial logistic regression using the backward stepwise selection method was performed to identify the risk factors associated with each of the eight domains of the LupusQoL among patients with inactive (SLEDAI < 4) and active (SLEDAI ≥ 4) SLE. RESULTS: HRQoL of our patients was classified as better in all domains of the LupusQoL. Age correlated negatively with all domains of the LupusQoL, except with "burden to others", and disease activity correlated negatively with all domains of the LupusQoL, except with "intimate relationships" and "burden to others" (p < 0.05). Patients who fully complied with indicated treatment had higher scores in "physical health" domain compared to patients who did not comply with at least one of the prescribed medications (p < 0.05). In patients with active SLE, a risk factor associated with worse "planning" and "intimate relationships" was advanced age, while having had SLE flare-ups in the previous six months was a risk factor associated with worse "physical health" (p < 0.05). CONCLUSION: Age and disease activity were negatively correlated with almost all domains of the LupusQoL, and treatment compliance was associated with higher score in the "physical health" domain. Disease control and treatment compliance should be the main goals for a better HRQoL in our patients with SLE.

10.
J Med Virol ; 94(3): 1175-1185, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34761824

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic has particularly affected countries with weakened health services in Latin America, where proper patient management could be a critical step to address the epidemic. In this study, we aimed to characterize and identify which epidemiological, clinical, and paraclinical risk factors defined COVID-19 infection from the first confirmed cases through the first epidemic wave in Venezuela. A retrospective analysis of consecutive suspected cases of COVID-19 admitted to a sentinel hospital was carried out, including 576 patient cases subsequently confirmed for severe acute respiratory syndrome coronavirus 2 infection. Of these, 162 (28.1%) patients met the definition criteria for severe/critical disease, and 414 (71.2%) were classified as mild/moderate disease. The mean age was 47 (SD 16) years, the majority of which were men (59.5%), and the most frequent comorbidity was arterial hypertension (23.3%). The most common symptoms included fever (88.7%), headache (65.6%), and dry cough (63.9%). Severe/critical disease affected mostly older males with low schooling (p < 0.001). Similarly, higher levels of glycemia, urea, aminotransferases, total bilirubin, lactate dehydrogenase, and erythrocyte sedimentation rate were observed in severe/critical disease patients compared to those with mild/moderate disease. Overall mortality was 7.6% (44/576), with 41.7% (28/68) dying in hospital. We identified risk factors related to COVID-19 infection, which could help healthcare providers take appropriate measures and prevent severe clinical outcomes. Our results suggest that the mortality registered by this disease in Venezuela during the first epidemic wave was underestimated. An increase in fatalities is expected to occur in the coming months unless measures that are more effective are implemented to mitigate the epidemic while the vaccination process is ongoing.


Assuntos
COVID-19 , COVID-19/diagnóstico , COVID-19/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Retrospectivos , SARS-CoV-2 , Venezuela/epidemiologia
13.
Front Public Health ; 9: 633723, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34327183

RESUMO

Background: The deterioration of Venezuela's health system in recent years undoubtedly contributes to an increased impact of the COVID-19 pandemic. Understanding healthcare workers' (HCWs) knowledge, attitudes, and practices (KAPs) toward COVID-19 in the early stages of the pandemic could inform their medical training and improve their preparedness. Methods: A online national cross-sectional survey was conducted between May 26th and May 30th, 2020, to assess KAPs among HCWs in Venezuela. Results: A total of 1,441 HCWs from all 24 regions of the country responded to the survey. The mean age of the HCWs was 44 (SD [standard deviation] 14) years; most were women (66.4%). Most HCWs were specialized doctors (48%), followed by nurses (13%) and resident doctors (12.3%). The majority of HCWs had good knowledge (76.3%), obtained information mainly from scientific literature (85.4%); had negative attitudes (53.6%), felt uncomfortable with their work during the current pandemic (59.8%); and reported appropriate practices (76.9%). However, participation in COVID-19 related training was absent in more than half of the HCWs. Positive attitudes were significantly more frequent in frontline workers than in non-frontline workers (p = 0.001). Bioanalysts, students, and doctors were more likely to have good knowledge; participating in training was a predictor for positive attitudes and older age was an appropriate practice predictor. Conclusions: HCWs, knowledge in Venezuela could be improved by strengthening education and training programs. Strategies should focus on reducing fear and improving attitudes toward the care of COVID-19 patients, as well as the promotion of preventive practices.


Assuntos
COVID-19 , Adolescente , Idoso , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Humanos , Pandemias , SARS-CoV-2 , Inquéritos e Questionários , Venezuela
14.
Phys Chem Chem Phys ; 23(7): 4133-4140, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33595039

RESUMO

Although aqueous biphasic systems have been largely investigated in the separation and/or purification of biocompounds, their potential as reaction media to design integrated reaction-separation processes has been less explored. In this work aqueous biphasic systems (ABSs) composed of polypropylene glycol of molecular weight 400 g mol-1 (PPG 400) and different polyethylene glycols (PEGs) were characterized, and investigated for integrated reaction-separation processes, i.e. in the nucleophilic degradation of diazinon and further separation of reaction products by taking advantage of the lower-critical solution temperature (LCST) behaviour of these ABSs. The nucleophilic degradation of diazinon was carried out in the monophasic regime at 298 K, after which an increase in temperature (up to 313 K) allowed the product separation by two-phase formation (thermoreversible systems). The reaction kinetics and reaction pathways have been determined. The reaction kinetic increases as the PEG molecular weight decreases, with the half-life values obtained being competitive to those previously reported using volatile organic solvents as solvent media and significantly higher than under alkaline hydrolysis. One reaction pathway occurs in ABSs comprising PEGs of higher molecular weights, whereas in the ABS composed of PEG 600 two reaction pathways have been identified, meaning that the reaction pathways can be tailored by changing the PEG nature. ABSs formed by PEGs of lower molecular weights were identified as the most promising option to separate the pesticide degradation products by simply applying changes in temperature.

15.
ACS Omega ; 5(41): 26562-26572, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33110984

RESUMO

A series of ionic liquids (ILs) composed by choline (Ch) as a cation and different amino acids (AA) as anions and their respective aqueous mixtures were prepared using different [Ch][AA] contents in a range of 0.4-46 mol % IL. These solvents were used for the first time to achieve an eco-friendlier Paraoxon degradation. The results show that [Ch][AA]/water mixtures are an effective reaction medium to degrade Paraoxon, even when the IL content in the mixture is low (0.4 mol % IL) and without the need of an extra nucleophile. Both the kinetics and the degradation pathways of pesticides depend on the nature of the AA on [Ch][AA] and the amount of an IL present in the mixture. We have demonstrated that in those mixtures with a low amount of [Ch][AA], the hydrolysis reaction is the main pathway for Paraoxon degradation, showing a catalytic effect of the IL. However, as the percentage of [Ch][AA] increases in the mixture, the nucleophilic attack of [Ch][AA] is evident. Finally, the aim of this study was to provide evidence of a promising and biocompatible methodology to degrade a toxic compound (Paraoxon) using a minimal quantity of an IL designed totally from natural resources.

16.
Org Biomol Chem ; 18(39): 7868-7875, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32985641

RESUMO

Propylene carbonate is becoming a suitable green alternative to volatile organic solvents in the study of chemical reactions. In this study, an efficient method for nucleophilic degradation of five organophosphorus pesticides, fenitrothion, malathion, diazinon, parathion, and paraoxon, using propylene carbonate as a solvent is proposed. The effect of changing the nature of the nucleophile and the influence of microwave (MW) heating were investigated. A screening of temperatures (50 °C-120 °C) was performed under microwave heating. The pesticide degradation was followed by 31P NMR, and the extent of conversion (%) was calculated by the integration of phosphorus signals. Keeping in mind that recently it has been reported that some ionic liquids play a nucleophilic role, in this work we report for the first time the degradation of organophosphorus pesticides by using an amino acid-based ionic liquid such as Bmim[Ala] as a nucleophile and a bio-based solvent (propylene carbonate) as a reaction medium in combination with microwave heating.

17.
Bol. venez. infectol ; 31(1): 29-36, ene-jun 2020.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1123249

RESUMO

La Toxoplasmosis y la Enfermedad de Chagas (ECh) son infecciones parasitarias frecuentes en Latinoamérica, capaces de ser transmitidas verticalmente durante el embarazo. Este trabajo tiene como objetivo determinar la seroprevalencia ante Trypanosoma cruzi (T. cruzi) y Toxoplasma gondii (T. gondii), en las embarazadas de la consulta prenatal del Ambulatorio Docente del Hospital Universitario de Caracas. Estudio analítico, prospectivo de corte transversal, realizado en 300 pacientes, en el lapso comprendido entre enero 2018 ­ marzo 2019. El 31,66 % de la población estudiada presentó seropositividad para anticuerpos IgG específicos para T. gondii, avidez de IgG mayor al 50 % e IgM negativa en todas, resultados compatibles con la fase crónica de la infección. Al correlacionar con los factores de riesgo habituales para la transmisión de T. gondii destacaron el contacto con heces de gato (46,3 %) y el consumo de agua directamente del grifo (32,6 %). En el caso de la ECh se demostró la presencia de factores de riesgo en la población estudiada, como contacto con triatominos (51,45 %) y viviendas cercanas a vegetación (49 %), sin embargo, solo una embarazada (0,33 %) demostró seropositividad para T. cruzi sin presentar relación con los factores de riesgo estudiados. Se evidenció una seroprevalencia muy frecuente para T. gondii y menor para T. cruzi, con factores de riesgo para la trasmisión vectorial cutánea y oral muy altos, constituyéndo una amenaza tanto para la embarazada como para al feto. Se recomienda educar a la población para reducir su exposición a factores de riesgo.


Toxoplasmosis and Chagas Disease (ChD) are frequent parasitic infections in Latin America, capables of vertical transmission during pregnancy. The purpose of this article is to determine the seroprevalence against Trypanosoma cruzi (T. cruzi) and Toxoplasma gondii (T. gondii), in pregnant women attending the prenatal clinic of the "Hospital Universitario de Caracas". Analytical, prospective study of a transversal cohort, carried out in 300 patients, during the period January 2018 - March 2019. The 31.66 % of the analyzed population showed seropositivity for IgG specific antibodies for T. gondii, all displaying an avidity IgG greater than 50 % and negative IgM, corresponding to a chronic stage of the infection. When correlating with the usual risk factors for the transmission of T. gondii, it was highlighted the presence of contact with cat feces (46.3 %) and the consumption of water directly from the tap (32.6 %). While with Chagas Disease (ChD), the presence of risk factors for acquiring the infection were highly demonstrated in the population, such as contact with triatomines (51.45 %) and living close to vegetation (49 %), however, only one pregnant woman (0.33 %) presented seropositivity for T. cruzi, without being related to the known risk factors. We conclude that T. gondii presents a high seroprevalence and T. cruzi an infrequent seroprevalence in the covered population, with high risk factors for cutaneous and oral vector transmission, representing a threat for the mother and the fetus. We recommend educating the population to reduce their exposure to risk factors.

18.
Org Biomol Chem ; 16(40): 7446-7453, 2018 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-30264845

RESUMO

The synthesis of a series of ionic liquids using 1-butyl 3-methylimidazolium (Bmim+) as a cation and different amino acids (AA) as anions (Bmim[AA]) is described. These ILs were used for the first time as reaction media to achieve more eco-friendly Paraoxon degradation. The results show that the degradation of Paraoxon in these Bmim[AA]s is accomplished with great efficiency and without an extra nucleophilic agent. Therefore, we propose that all the Bmim[AA]s used in this study have a dual role in the outcome of this reaction; as a nucleophile and a solvent to carry out degradation of the organophosphorous pesticide, Paraoxon. Both kinetics and product distribution results found in this study for Paraoxon degradation turned out to be promising, because this process is achieved in a reaction medium with a better environmental profile.

19.
Front Chem ; 6: 669, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30693279

RESUMO

An efficient strategy for the degradation of organophosphate pesticide Diazinon was investigated. In this work, ionic liquids, bio-based solvents, and two conventional organic solvents were used as reaction media. Kinetics studies by means of half-life (t1/2,h) were followed by 31P NMR and the products analyzed by GC-MS, HPLC-MS and NMR techniques. These results have shown that t1/2 values in ionic liquids were the lowest and also they were able to activate two electrophilic centers in Diazinon, whilst degradation in bio-based solvents occurred slowly by only an aromatic pathway. In addition, a study to estimate the influence of green activation techniques was carried out by using Ultrasound irradiation and Microwave heating in combination with greener solvents and two conventional organic solvents. Under Microwave heating, faster degradation than under ultrasound irradiation was found. Finally, considering both families of solvent used here and their behavior under green activation techniques, we propose that the more efficient way for degradation of Diazinon with piperidine is by microwave heating using ionic liquids as solvents.

20.
Org Biomol Chem ; 14(4): 1502, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26753531

RESUMO

Correction for 'Reaction mechanisms in ionic liquids: the kinetics and mechanism of the reaction of O,O-diethyl (2,4-dinitrophenyl) phosphate triester with secondary alicyclic amines' by Paulina Pavez et al., Org. Biomol. Chem., 2016, DOI: 10.1039/c5ob02128f.

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