Validation of a modified QuEChERS method for the quantification of residues of currently used pesticides in Cuban agricultural soils, using gas chromatography tandem mass spectrometry.

We present an analytical method to detect and quantify residues of currently used pesticides (CUPs), which include 31 active ingredients (ai) and seven transformation products (TPs) in tropical and agricultural soils of Cuba. Ten isotopically labeled analogous compounds served as internal standards (IL-IS). The novelty of this research is the inclusion of different tropical soils type scarcely studied for CUPs and TPs, based on the QuEChERS (quick, easy, cheap, effective, rugged and safe) method, followed by chromatography tandem mass spectrometry. All figures of merit proved to be satisfactory according to SANTE guidelines 2020 and 2021. Matrix effects (ME) calculated by the external standard method were significant (|ME| > 20% for almost all compounds; grand mean ± standard deviation (STD) 104 ± 108%) in all soils. The internal standard method compensated ME to non-significant levels (8 ± 50%), even for analytes with a non-structure identical IL-IS (STD, 13 ± 57%). Repeatability (relative standard deviation, RSDr) and reproducibility (RSDR) for skeletic regosol (SR) were 7.5 ± 2.8% and 11.7 ± 4.7%, respectively. Absolute (quantified for 11 analytes with structure identical IL-IS) and relative recovery from SR was 92 ± 13% (mean ± STD) and 90 ± 12%, respectively. Limits of quantification for SR ranged from 0.1 to 10 ng/g, except metalaxyl and oxyfluorfen (25 ng/g each). Linearity of matrix-matched (MM) calibration curves (5 to 100 ng/g) had an R2 of ≥ 0.99 for all soils and almost all analytes. The method was successfully applied to 30 real soil samples.

Stroke care and collaborative academic research in Latin America.

OBJECTIVE: A narrative overview of regional academic research collaborations to address the increasing burden and gaps in care for patients at risk of, and who suffer from, stroke in Latin America (LA). MATERIALS AND METHODS: A summary of experiences and knowledge of the local situation is presented. No systematic literature review was performed. RESULTS: The rapidly increasing burden of stroke poses immense challenges in LA, where prevention and manage-ment strategies are highly uneven and inadequate. Clinical research is increasing through various academic consortia and networks formed to overcome structural, funding and skill barriers. However, strengthening the ability to generate, analyze and interpret randomized evidence is central to further develop effective therapies and healthcare systems in LA. CONCLUSIONS: Regional networks foster the conduct of multicenter studies -particularly randomized controlled trials-, even in resource-poor regions. They also contribute to the external validity of international studies and strengthen systems of care, clinical skills, critical thinking, and international knowledge exchange.

Heavy metals in soils of Mayabeque, Cuba: multifaceted and hardly discernable contributions from pedogenic and anthropogenic sources.

Cuba is a country with considerable potential for economic growth, and special efforts are made to increase the agricultural output. As food production depends on the quality of soils, heavy metal concentrations were measured in 39 soils in the province of Mayabeque, Cuba, and interpreted in light of anthropogenic activities and pedogenic conditions (soil type and properties). With median concentrations of 1.8 Cd, 60.3 Cr, 48.1 Cu, 36.2 Ni, 16.7 Pb, 55.0 Zn, and 0.1 mg/kg Hg, soils of Mayabeque were mostly below Cuban quality reference values (QRV) representing benchmarks of quality standards but no official threshold values. Only Cd concentrations were in many cases above the QRV of 0.6 mg/kg and some Cu concentrations above the one of 83 mg/kg. While Cd, Cr, and Ni concentrations were rather pedogenically driven, Cu, Pb, Zn, and Hg contents were rather anthropogenically influenced. When evaluated statistically, Cd and Cr showed most times a significant influence of both sources. In contrast, Ni and Zn could not be significantly related with the origins investigated in this study. Hence, the allocation of heavy metal concentrations to pedogenic or anthropogenic contamination or pollution sources is tentative and needs further investigations. Nevertheless, the present data adds information on soil heavy metal concentrations in the Caribbean region, serves as reference before further industrial development, and sets the ground for adaptation of the QRV for Cd and possibly future national environmental standards.

Fungal Invasive Co-Infection Due to Aspergillus fumigatus and Rhizopus arrhizus: A Rhino-Orbital Presentation.

Aspergillosis and mucormycosis are filamentous fungal infections occurring predominantly in immunocompromised patients. Fulminant process with rapid infiltration of the contiguous tissue is distinctive for both type of fungi. The rhinocerebral co-infection by Aspergillus and Mucorales is very rare and is usually associated in immunocompromised patients with a high mortality rate. This rare co-infection leads to difficulties in diagnosis, and therapeutic delays can result in a poor prognosis. Overall, the treatment of choice is surgical debridement and liposomal amphotericin B. This paper describes a combined aspergillosis and mucormycosis case in a diabetes mellitus type 2 patient with chronic ulcerations of the palatal and cheek. To our knowledge, this is the first report of an uncommon co-infection of Aspergillus fumigatus and Rhizopus arrhizus in a rhino-orbital presentation.

Polycyclic aromatic hydrocarbons and polychlorinated biphenyls in soils of Mayabeque, Cuba.

Cuba is a country in transition with a considerable potential for economic growth. Soils are recipients and integrators of chemical pollution, a frequent negative side effect of increasing industrial activities. Therefore, we established a soil monitoring network to monitor polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in soils of Mayabeque, a Cuban province southeast of Havana. Concentrations of the sum of the 16 US EPA PAHs and of the seven IRMM PCBs in soils from 39 locations ranged from 20 to 106 µg kg-1 and from 1.1 to 7.6 µg kg-1, respectively. While such concentrations can be considered as low overall, they were in several cases correlated with the distance of sampling sites to presumed major emission sources, with some of the concomitantly investigated source diagnostic PAH ratios, and with black carbon content. The presented data adds to the limited information on soil pollution in the Caribbean region and serves as a reference time point before the onset of a possible further industrial development in Cuba. It also forms the basis to set up and adapt national environmental standards.

Polychlorinated biphenyls (PCBs) residues in milk from an agroindustrial zone of Tuxpan, Veracruz, Mexico.

The coasts of the Gulf of Mexico are zones exposed to the exploration and exploitation of petroleum sources, and the products generated in agricultural zones may become contaminated by persistent organic pollutants (POPs). The objective of the present study was to evaluate the presence of polychlorinated biphenyl compounds (PCBs) in milk from dairy production units near sources of environmental pollutants. It was confirmed that the seven congeners of nondioxin-like PCBs (NDL-PCBs) are present in milk where compounds PCB101, PCB118, PCB153 and PCB180 appear in 100% of the samples analyzed, the rank of concentration for the sum of the seven congeners fluctuating between 2.6 and 26 ng g(-1) with a median of 6 ng g(-1). None of the samples surpassed the provisional value established by the EU of 40 ng g(-1) of milk fat for the sum of the seven congeners, indicator that was not affected by the season of the year (p<0.05), whose median of 8.6 ng g(-1) and 6.3 ng g(-1) for rain and drought respectively. The concentrations of NDL-PCBs found in milk do not represent a problem for human health; however, they alert the existence of spontaneously generated, uncontrolled sources that may represent a potential danger for human and animal health.

Incidence of lobar and non-lobar spontaneous intracerebral haemorrhage in a predominantly Hispanic-Mestizo population--the PISCIS stroke project: a community-based prospective study in Iquique, Chile.

BACKGROUND: The incidence of intracerebral haemorrhage (ICH) in Hispanics is high, especially of non-lobar ICH. Our aim was to ascertain prospectively the incidence of first-ever spontaneous ICH (SICH) stratified by localisation in a Hispanic-Mestizo population of the north of Chile. METHODS: Between July 2000 and June 2002 all possible cases of ICH were ascertained from multiple overlapping sources. The cases were allocated according to localisation. Those with vascular malformations or non-identifiable localisations were excluded. RESULTS: We identified a total of 69 cases of first-ever ICH. Of these, 64 (92.7%) had SICH, of which we allocated 58 cases (84%) to non-lobar or lobar localisation. The mean age was 57.3 +/- 17 years, and 62.3% of the subjects were male. The age-adjusted incidence rates were 13.8 (non-lobar) and 4.9 (lobar) per 100,000 person-years. Non-lobar SICH was more frequent in young males and lobar SICH in older women. The non-lobar-to-lobar ratio was similar to previous findings in Hispanics. Hypertension was more frequent in non-lobar SICH and in diabetes, heavy drinking and antithrombotic use in lobar SICH, but in none significantly. There was no association between localisation and prognosis. CONCLUSIONS: The incidence of non-lobar SICH was high, but lower than in most non-white populations. This lower incidence could be due to a lower population prevalence of risk factors, a higher socioeconomic level in this population, or chance.

Detection of Rubisco and mycotoxins as potential contaminants of a plantibody against the hepatitis B surface antigen purified from tobacco.

Antibodies have been one of the proteins widely expressed in tobacco plants for pharmaceutical purposes, which demand contaminant free preparations. Rubisco constitutes 40-60% of tobacco leaf soluble proteins; therefore it is the major potential protein contaminant of plantibodies, while mycotoxins are toxic compounds that could be introduced during the biomass production and post-harvest stages with important consequences to human health. The objective of this paper was to investigate whether Rubisco and mycotoxins are present in Plantibody HB-01 preparations used in the immunopurification of the hepatitis B surface antigen. Rubisco was purified from Nicotiana tabacum yielding 154 microg of protein per gram of leaves and purity over 95%. Among mouse monoclonal antibodies generated against this enzyme, the CBSS.Rub-2 was selected for its immunodetection. It recognizes a conserved sequential epitope of Rubisco large subunit with an affinity constant of 0.13 x 10(8)M(-1). Rubisco quantification limit was 1 microg spreading to the measurement of this contaminant less than 4% of plantibodies samples. Additionally, according to a Reverse Phase-HPLC used to measure the level of adventitiously introduced contaminants, it can be concluded that aflatoxins B1, B2, G1 and G2 were undetected in the purified Plantibody HB-01 samples.

Incidence, case-fatality rate, and prognosis of ischaemic stroke subtypes in a predominantly Hispanic-Mestizo population in Iquique, Chile (PISCIS project): a community-based incidence study.

BACKGROUND: Incidence of ischaemic stroke subtypes, classified by cause, seems to vary between communities. We aimed to prospectively ascertain the incidence of first-ever ischaemic stroke in a predominantly Hispanic-Mestizo population in the northern desertic region of Chile. METHODS: Between July, 2000, and June, 2002, all patients with possible stroke or transient ischaemic attacks were identified from multiple overlapping sources and were rapidly assessed by two field neurologists. All identified patients were diagnosed by at least two stroke neurologists according to Trial of Org 10172 in Acute Stroke Treatment (TOAST) definitions and were followed up at 6 months. Annual incidence rates were age adjusted to WHO, European, and US populations by the direct method to allow comparisons. FINDINGS: A total of 239 ischaemic strokes were identified, of which 185 (77%) were first-ever cases. 151 (82%) patients were hospitalised, of whom only 70 (38%) were assessed within 6 h of symptom onset. The mean age of patients was 66.4 years (SD 14.9) and 56% were men. The crude annual incidence rates (per 100 000) according to stroke subtype were: cardioembolic, 9.3; large-artery disease, 2.0; small-vessel disease, 15.8; other determined cause, 0.2; and undetermined cause, 17.4. Hypertension was the most common cardiovascular risk factor in all subtypes and atrial fibrillation was the most common cause of cardioembolic stroke. Case fatality at 30 days was highest in cardioembolic strokes (28%) and lowest in small-vessel disease (0%). Dependency or death at 6 months was also highest in cardioembolic strokes (62%) and lowest in small-vessel disease (21%). INTERPRETATION: Incidence and prognosis of small vessel and cardioembolic infarction was similar to that in other populations and incidence of large-artery atherothrombotic infarction was lower than in most previous reports. Hypertension and atrial fibrillation were the most common risk factor and cause, respectively, of ischemic stroke in this population. These findings should help the national stroke programme in the prevention of cardioembolic stroke, increase access to specialists and acute brain imaging and vascular studies, and improve stroke care.

Polyphenol and phytosterol composition in an antibacterial extract from Rhizophora mangle L. bark.

Rhizophora mangle L. bark aqueous extract has antimicrobial, wound healing and antiulcerogenic properties. These properties could be associated with its chemical composition. To test this hypothesis, gravimetric, colorimetric, gas chromatography techniques were used to determine the preliminary chemical composition of this extract. Sephadex LH-20 Exclusion Chromatography was used by the fractionation of total extract and fractionation of low molecular weight polyphenols by liquid/liquid extraction. High Performance Liquid Chromatography was used to perform the composition in this low molecular weigh polyphenols fraction. The extract presented polyphenolic structures (54.78%) and other structural components (45.22%). Polymeric tannins were the major polyphenolic component (80%) and 20% were hydrolysable tannins. Epicatechin, catechin, chlorogenic acid, gallic acid and ellagic acid were monomeric structures determined in this extract. Phytosterols (0.0285%): stigmasterol, beta-sitosterol and campesterol were also present.

COX-2 and sPLA2 inhibitory activity of aqueous extract and polyphenols of Rhizophora mangle (red mangrove).

The aqueous extract of Rhizophora mangle bark and its polyphenolic fractions showed remarkable in vitro antiinflammatory activity in a preliminary study. The low molecular weight fraction exhibited cyclooxygenase-2 inhibitory activity while the total aqueous extract and the low molecular weight fraction showed secretory phospholipase A(2) inhibitory activity.

Antioxidant activity of Rhizophora mangle bark.

The antioxidant activity of Rhizophora mangle bark aqueous extract and its majoritary component and high molecular weight polyphenols' fraction were studied using deoxyribose assay. The total extract and its fraction showed scavenging activity of hydroxyl radicals and hability to chelate iron ions.

Incidence, 30-day case-fatality rate, and prognosis of stroke in Iquique, Chile: a 2-year community-based prospective study (PISCIS project).

BACKGROUND: The epidemiology of stroke in Latin-American populations and variation of subtypes between communities are unclear. Our aim was to ascertain prospectively the incidence of first-ever stroke in the predominantly Hispanic-Mestizo population of Iquique, a city in the northern desert region of Chile. METHODS: We prospectively identified all possible cases of stroke and transient ischaemic attacks between July 1, 2000, and June 30, 2002, from several overlapping sources. Patients were rapidly assessed by two field neurologists. Standard definitions for incident cases, stroke, transient ischaemic attack, pathological type, and infarction subtype were used. All cases identified were adjudicated by at least two stroke neurologists and followed up at 6 months. Incidence rates of first-ever strokes were calculated from the population of Iquique (214 526) according to the national census of 2002. FINDINGS: Of 380 cases of stroke identified, 292 were incident. CT scans were done in 267 (91%) patients and the mean time to scan was 2.2 days. The hospital admission rate was 71% (207/292). The overall age-adjusted incidence rate of first-ever stroke was 140.1 per 100,000 (95% CI 124.0-156.2). The incidence rates per 100,000 according to pathological type were: infarcts 87.3, intracerebral haemorrhage 27.6, and subarachnoid haemorrhage 6.2. The 30 day and 6-month case-fatality rates were 23.3% and 33.0%, respectively. INTERPRETATION: Our results show incidence rates of stroke similar to those reported in other community studies. Although the proportion of intracerebral haemorrhages was higher than reported in previous studies, the overall incidence was not, which could indicate a slightly lower incidence of ischaemic strokes in this population than in other countries. The prognosis was similar to that found in other population-based studies.

[Labor absenteeism in a social security institution and some related factors]. / Ausentismo laboral en una institución de seguridad social y factores relacionados.

OBJECTIVE: To analyse the sociocultural and organizational factors of the health services related to the unplanned absenteeism. MATERIAL AND METHODS: By means of a cross and descriptive analysis, a group of workers from a Social Security Institution was studied. The previous year, this group presented a significant absenteeism, which means that the worker had stayed away from his work-place more than 12 working days in the year of 2003. After having the consent of the worker, a medical-social study took place at the worker's home. Descriptive statistics and correlation of Pearson were used. RESULTS: The average age was of 40.6 +/- 7.7 years old; 68.8 % of them were married, and the integrated family represented the 74 %. The group of age which had the greatest percentage of absenteeism was the one of 41 to 50 years old, with 49.2 %. The correlation between years of seniority and absenteeism was 0.027 (p = ns). The activity performed by 87 % of the workers was related to their profession or labor profile. CONCLUSIONS: The greatest absenteeism percentage corresponds to the group of age between 41 and 50 years old, and there was no correlation found between seniority and absenteeism; however, there is an adequate satisfaction with the activities that they carry out in their work-place.

Determination of aflatoxin B1 in food and feedstuffs in Cuba (1990 through 1996) using an immunoenzymatic reagent kit (Aflacen).

The presence of aflatoxin B1 was analyzed in imported food and feedstuffs of national production in the period of 1990 through 1996, destined to animal and human consumption using an immunoenzymatic reagent kit (Aflacen, Ckure, la Habana, Cuba) with a detection limit of 0.3 microg/kg. It was found that the 17.04% of a total of 4,594 analyzed samples presented aflatoxin B1, and the biggest percentages were in sorghum and peanut with an 83.3 and 40.4%, respectively. The corn, oat, wheat, and soy are fundamental raw ingredients in the elaboration of concentrates. Percentages of contamination with aflatoxin B1 of 23.3, 10.7, 25, and 4.6 were found in corn, oat, wheat, and soy, respectively. Other analyzed foods like rice, beans, and peas presented percentages of contamination with aflatoxin B1 inferior to 5% of the analyzed samples. It was found that more than 455 samples surpassed the value of 10 microg/kg. Corn and peanut products present a high demand in population showing levels of contamination superior to 50 microg/kg. The 11.3% of the samples contaminated with aflatoxin B1 have values between 1 and 20 microg/kg, where peanut and concentrates show the highest percentages (21.9 and 18.7), respectively. These results show levels of aflatoxin B1 in the population that constitute a great risk for human and animal health.