Occupational Exposure to Alcohol-Based Hand Sanitizers: The Diagnostic Role of Alcohol Biomarkers in Hair.

Ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEEs) in hair are effective direct biomarkers of ethanol ingestion, whose analytical determination can be used to discriminate between chronic and occasional ethanol intake. Ethanol is a compound widely used in some workplaces (e.g., clinics, hospitals) and is present in considerable amounts in mouthwash for oral cleaning, medications, cosmetic products, hydro-alcoholic disinfectants and antiseptics for hands. This study examined the ethyl alcohol exposure derived from hand disinfectants (in gel form) by simulating the typical occupational situation of medical-health workers (healthcare workers, nurses, surgeons, etc.) who frequently wash their hands with antiseptic sanitizer. Two types of hand disinfectants with 62% w/w of ethanol content were daily applied to the hands of a teetotaler for 20 times a day, for 4 consecutive weeks, thus simulating a typical workplace situation and a cumulative dermal exposure to ethanol of ~1,100 g. Different matrices (head, chest and beard hair, urine) were regularly sampled and analyzed using a ultra high-performance liquid chromatography tandem massspectrometry validated method for EtG and a (HS)SPME-GC-MS validated technique for FAEEs. The data obtained showed that a significant dermal absorption and/or inhalation of ethanol occurred, and that the use of detergents produce urinary EtG concentrations both higher than the cut-offs normally used for clinical and forensic analyses (either 100 and 500 ng/mL, depending on the context). The concentrations of the ethanol metabolites in the keratin matrices were, respectively, below the cut-off of 7 pg/mg for EtG and below 0.5 ng/mg for FAAEs (0.35 ng/mg for ethyl palmitate). In conclusion, the regular use of alcohol-based hand sanitizers can affect the concentration of urinary EtG and lead to positive analytical results, particularly when specimens are obtained shortly after sustained use of ethanol-containing hand sanitizer. On the other hand, direct biomarkers of alcohol abuse in the keratin matrix are capable of distinguishing between ethanol consumption and incidental exposures.

The effect of chronic stress on prenatal development of the central nervous system.

The survival of developing embryos depends on the control and maintenance of homeostasis. Stress caused by chronic immobilization during pregnancy in rats may alter the normal development of the nervous system and increase susceptibility to psychiatric disorders. We investigated the effects of chronic stress on cell proliferation in the forebrains of embryos at 12 days of gestation, and in the hippocampus, dentate gyrus and cortex in embryos at 17 and 21 days of gestation. We examined serial sections of the embryonic brains of control and stressed rats at days 12, 17 and 21 of gestation. Brain sections were immunolabeled with anti-PCNA and stereological analysis was performed on 540 images. The results showed no statistical differences on days 12 and 17 of gestation in the proliferation area of the structures studied, whereas on day 21 of gestation, proliferation decreased in the cortex and dentate gyrus of embryos of the stressed group. These changes were related to decreased prolactin and increased corticosterone concentrations in the plasma.

Chronic stress and its effects on adrenal cortex apoptosis in pregnant rats.

The model of chronic intermittent stress by immobilization during pregnancy may produce alterations in the mechanisms that maintain adrenal gland homeostasis. In earlier investigations using this model, significant variations in plasma prolactin and corticosterone levels, and adrenal gland weights were observed. We hypothesized that chronic stress causes changes in apoptosis in the adrenal glands of pregnant rats. We identified and quantified apoptotic cells in the adrenal cortex and examined their ultrastructural characteristics using transmission electron microscopy. Adrenal glands of pregnant rats at gestation days 12, 17 and 21 were studied for control and experimental (stressed) rats. Immunolabelling techniques, stereological analysis and image quantification of adrenal gland sections were combined to determine differences in apoptosis in the different cell populations of the adrenal cortex. The apoptotic index of the experimental rats showed a significant reduction at gestation day 17, while at days 12 and 21 there were no differences from controls. Moreover, the apoptotic index of the reticular zones in control and experimental animals showed a significant increase compared to the glomerular and fascicular zones at the three gestation times studied. Chronic stress by immobilization reduced the caspase-dependent apoptotic index at gestation day 17, which may be related to variations in plasma concentrations of estrogens and prolactin.

Ultrastructural study of spermatogenesis in Eisenia foetida (Annelida, Oligochaeta)

La espermatogénesis y ultraestructura del espermatozoide siguen un patrón común en los oligoquetos terrestres, sin embargo, muchos de sus aspectos son distintivos de cada especie y tienen importancia para los estudios filogenéticos y taxonómicos. Con el objetivo de profundizar sobre aspectos de la espermatogénesis y, en especial, sobre la ultraestructura del espermatozoide maduro de Eisenia foetida, se estudiaron sus células germinales mediante técnicas convencionales de microscopía electrónica. La espermatogénesis ocurre en las vesículas seminales y sigue un patrón comparable con el de otras especies de oligoquetos. Los detalles ultraestructurales del espermatozoide revelaron que es una célula filiforme, con el acrosoma situado en posición anterior, seguido por el núcleo, pieza intermedia y cola, la que posee el flagelo con la configuración microtubular típica de 9+2. Podemos concluir que el espermatozoide de Eisenia foetida es del tipo apomórfico,ya que presenta varias características consideradas evolucionadas, como son: acrosoma muy largo, vesícula acrosómica primaria contenida dentro del tubo acrosómico, varilla axial muy extendida y terminada en un capítulo desarrollado y el número de mitocondrias de la pieza intermedia igual a seis.

Spermatogenesis and the spermatozoon ultrastructure follow a common pattern in terrestrial oligochaetes. However, many of their characteristics are distinctive of each species and they are of great importance for phylogenetic and taxonomic studies. Germinal cells were studied through conventional electronic microscope techniques in order to go deep on spermatogenesis, especially on the mature spermatozoon ultrastructure of Eisenia foetida. Spermatogenesis occurs in seminal vesicles and follows a pattern comparable to that of some other oligachaetes species. Spermatozoon ultrastructural details revealed that it is a filiform cell, with the acrosome placed in anterior position, followed by the nucleus, the midpiece and the tail which flagellum has a 9+2 typical microtubular configuration. We may conclude that Eisenia foetida spermatozoon is of a apomorphic type since it presents several evolved characteristics such as: a very large acrosome; the primary acrosomic vesicle is held within the acrosomal tube, the axial rod is very elongated and ended in a developed capitulum and a number of mitochondria of the midpiece equal to six.

Relative Concentrations of Placental Lactogen II and PRL-Like Protein-A in Stressed Rats Placenta / Concentraciones del Lactógeno Placentario II y la Proteína A Ligada a Prolactina en Placentas de Ratas Estresadas

The chronic stress induces functional adaptations in the hypothalamo-pituitary- adrenocortical (HPA) and in the sympathetic-medullary-adrenal axis (SAM). Both axis are considered vital regulators of the homeostasis in vertebrates (Seyle, 1936; Ostrandrer et al, 2006. On the other hand, the placenta provides highly specialized functions during gestation that are critical for the normal development of the embryo/fetus (Soares et al., 1991). We hypothesized that the chronic immobilization (IMO) stress in pregnancy rats produces alterations in prolactin concentrations in placental tissue and also changes in the response of SAM axis. Chronic stress by IMO was applied on days 12, 17 and 21 of pregnancy rats. Relative concentrations and localization of placental lactogen-II (PL-II) and the PRL- like protein A (PLP-A) in chorioalantoic placenta were estimated by Immunoblotting and Immunocytochemical analysis. The levels of catecholamines metabolite, acid 3-metoxi 4-hidroximandélico (VMA), were analyzed in stressed rats urines on 6,12,17,21 days of pregnancy, by HPLC, in order to determine the response of SAM axis. During the days of the pregnancy studied, chronic stress did not induce any changes neither in the localization nor in placental concentrations of PL-II and PLP-A. The VMA values in stressed mothers urines increased on the day 6 respecting the control ones at the same time of pregnancy. VMA values in stressed rats at 21 days of pregnancy are smaller than the respective controls. We conclude that the chronic stressed mothers activated the SAM axis at the beginning of pregnancy and then they diminished the metabolites catecholamines that were interpreted as a stress adaptation coincident with normal concentrations of both placentary prolactines at this stage of the pregnancy.

El estrés crónico induce adaptaciones funcionales en los ejes hipotálamo-pituitario-adrenal (UPA) y en el simpático médulo adrenal (SAM). Ambos ejes son considerados reguladores vitales de la homeostasis en los vertebrados (Seyle, 1936; Ostrandrereí al., 2006). Por otro lado, el desarrollo y crecimiento fetal de los mamíferos dependen en gran medida del buen funcionamiento de la placenta (Soares, 1991). Nosotros hipotetizamos que el estrés crónico por inmovilización (IMO) aplicado a las ratas gestantes produce alteraciones en las concentraciones de las prolactinas en el tejido placentario y cambios en la respuesta del eje SAM. Se le aplicó estrés crónico por IMO a las hembras en los días 12, 17 y 21 de la preñez y se analizó por inmunocitoquímica e inmunoblotting la localización y concentraciones del lactógeno placentario dos (PL-II) y la proteína A ligada a la prolactina (PLP-A) en la placenta. Se analizaron por HPLC, en las orinas de ratas preñadas (6,12,17,21 días), los niveles del metabolito de las catecolaminas, (ácido 3-metoxi 4-hidroximandélico) (VMA), a fin de determinar la respuesta del eje SAM al tratamiento. El estrés crónico no indujo cambios tanto en la localización como en las concentraciones de PL-II y PLP-A en las placentas en los días de la preñez estudiados. Los valores de VMA en las orinas de las madres estresadas se incrementaron en el día 6 con respecto al control del mismo tiempo de preñez. Mientras que a los 21 días los valores de VMA de las ratas estresadas son menores que los controles respectivos. Concluimos que en las madres estresadas crónicamente, no se alteraron las concentraciones de ambas prolactinas placentarias. En cambio se activó el eje SAM al comienzo de la preñez ante el primer estímulo estresante y luego una reducción de la respuesta del eje ante el estrés crónico, a medida que avanza la preñez.

Chronic stress effects on the apoptotic index of the adrenal cortex of pregnant rats

Chronic stress by immobilization during gestation can alter several mechanisms that maintain homeostasis in adrenal gland. The aim of this work was to quantify the apoptotic index of adrenal cortex during mid-pregnancy and to prove cytological characteristics by electron microscopy. The apoptotic index did not present significant differences between the adrenal cortex areas of control and experimental rats in any of the three ages studied. The day of gestation influenced significantly on the apoptotic index in both groups. This index increased as gestation progressed. It may be concluded that chronic stress by immobilization might induce the increase of apoptotic index in adrenal cortex as gestation progresses which might be related variations of plasmatic corticosterone and prolactin, and to the decrease of specific growth factors. On the other hand, it might be concluded that each zone of adrenal cortex behaves independently in regards to apoptosis and cellular proliferation via paracrine and/or autocrine regulatory mechanisms without being affected by other zones.

Chronic stress effects on the apoptotic index of the adrenal cortex of pregnant rats

Chronic stress by immobilization during gestation can alter several mechanisms that maintain homeostasis in adrenal gland. The aim of this work was to quantify the apoptotic index of adrenal cortex during mid-pregnancy and to prove cytological characteristics by electron microscopy. The apoptotic index did not present significant differences between the adrenal cortex areas of control and experimental rats in any of the three ages studied. The day of gestation influenced significantly on the apoptotic index in both groups. This index increased as gestation progressed. It may be concluded that chronic stress by immobilization might induce the increase of apoptotic index in adrenal cortex as gestation progresses which might be related variations of plasmatic corticosterone and prolactin, and to the decrease of specific growth factors. On the other hand, it might be concluded that each zone of adrenal cortex behaves independently in regards to apoptosis and cellular proliferation via paracrine and/or autocrine regulatory mechanisms without being affected by other zones.(AU)