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This work presents the development, synthesis, and application of a layered double hydroxide (LDH) coupled to magnetic particles for the removal of antibiotics as tetracyclines (TC´s): tetracycline (TC), chlortetracycline (CT), oxytetracycline (OT), and doxycycline (DT) from milk samples. The LDH synthesis conditions, reaction time (30-90 min), molar ratios Mg2+/Al3+ (7:1-1:7), interlayer anion (NO3-, Cl-, CO32-, and dodecyl sulphate (DS-)) were evaluated. Under synthesis conditions (reaction time of 30 min, Mg2+/Al3+ molar ratio of 7:1, and DS- as interlayer anion), the LDH was coupled in a magnetic solid phase microextraction (MSPµE) methodology. At the optimal extraction conditions (pH 6, 5 min of contact time, 10 mg of adsorbent), a removal percentage of 99.0 % was obtained for each tetracycline. FTIR, TGA, SEM, and adsorption isotherms were employed to characterize the optimal adsorbent. Each experiment was corroborated by large-volume sample stacking capillary electrophoresis (LVSS-CE). The adsorbent was applied directly to positive milk samples (previously tested) for TC´s removal.

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Plant viruses such as brome mosaic virus and cowpea chlorotic mottle virus are effectively purified through PEG precipitation and sucrose cushion ultracentrifugation. Increasing ionic strength and an alkaline pH cause the viruses to swell and disassemble into coat protein subunits. The coat proteins can be reassembled into stable virus-like particles (VLPs) that carry anionic molecules at low ionic strength and through two-step dialysis from neutral pH to acidic buffer. VLPs have been extensively studied due to their ability to protect and deliver cargo, particularly RNA, while avoiding degradation under physiological conditions. Furthermore, chemical functionalization of the surface of VLPs allows for the targeted drug delivery. VLPs derived from plants have demonstrated great potential in nanomedicine by offering a versatile platform for drug delivery, imaging, and therapeutic applications.

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Latiné people differ markedly in our lived experiences in ways that are underappreciated. Meanwhile, variations in social experiences are known to be associated with differential health outcomes. We test whether immigration history is associated with health differences among U.S.-based Cuban refugees. Cubans from the circum-1980 Mariel Boatlift migration wave reported significantly higher instances of disability than Early Cuban Exiles, Freedom Flight refugees, and Special Period refugees. We also interviewed Miami-based Cubans. Participants described heightened discrimination in 1980s Cuba and U.S., which we hypothesize contributed to higher instances of disability refugees of that era. By understanding how differential social experiences shape health, we aim to provide a nuanced understanding of the social determinants of health and the ways adverse experiences can be combated.

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Resumen La interacción entre la madre y el feto durante el embarazo se ha estudiado exhaustivamente. Una de estas interacciones es el microquimerismo, el cual se caracteriza por un intercambio madre-feto de células y material genético. Adicional a la gestación, la madre hereda más células por medio de la lactancia, donde se transfieren biocomponentes (células, anticuerpos y bacterias comensales) que juegan un papel importante en la adaptación del recién nacido al medio. Las consecuencias de este microquimerismo posparto genera beneficios directos en los primeros meses de vida, previniendo enfermedades e infecciones, induciendo tolerancia a moléculas inocuas, así como favoreciendo el entrenamiento inmunitario del recién nacido, con respuestas dirigidas y beneficios en la vida adulta. Es destacable que el microquimerismo materno podría interpretarse como un legado inmunológico en el neonato, el cual es perdurable para algunos de sus componentes y definitorio en el correcto desarrollo de la progenie.

Abstract The interaction between mother and fetus during pregnancy has been extensively studied. One of these interactions is the microchimerism, which is characterized by a mother-fetus exchange of cells and genetic material. In addition to gestation, the mother inherits more cells through lactation, in which biocomponents (cells, antibodies, and commensal bacteria) that play an important role in the adaptation of the newborn to the environment are transferred. The consequences of this post-partum microchimerism generate direct benefits in the first months of life, preventing diseases and infections, inducing tolerance to innocuous molecules, as well as favoring the immunological training of the newborn, with specialized responses and benefits in adult life. It is noteworthy that maternal microchimerism could be interpreted as an immunological legacy in the neonate, which is lasting for some of its components, and defining in the correct development of the progeny.

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Over the last 20 years, the incidence of vertical HIV transmission has decreased from 25%-42% to less than 1%. Although there are no signs of infection, the health of HIV-exposed uninfected (HEU) infants is notoriously affected during the first months of life, with opportunistic infections being the most common disease. Some studies have reported effects on the vertical transfer of antibodies, but little is known about the subclass distribution of these antibodies. We proposed to evaluate the total IgG concentration and its subclasses in HIV+ mothers and HEU pairs and to determine which maternal factors condition their levels. In this study, plasma from 69 HEU newborns, their mothers, and 71 control pairs was quantified via immunoassays for each IgG isotype. Furthermore, we followed the antibody profile of HEUs throughout the first year of life. We showed that mothers present an antibody profile characterized by high concentrations of IgG1 and IgG3 but reduced IgG2, and HEU infants are born with an IgG subclass profile similar to that of their maternal pair. Interestingly, this passively transferred profile could remain influenced even during their own antibody production in HEU infants, depending on maternal conditions such as CD4+ T-cell counts and maternal antiretroviral treatment. Our findings indicate that HEU infants exhibit an altered IgG subclass profile influenced by maternal factors, potentially contributing to their increased susceptibility to infections.

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Breastfeeding is recognized worldwide as the best option for infant feeding. Expressing breast milk is an alternative for mothers to provide their infants all the benefits of maternal milk. During breast milk expression, mothers receive a distinct kind of sensory stimulation, because there is no direct bodily or affective interaction with their infants, many women report feeling isolated, generating a love-hate relation with pumping, and even low levels of satisfaction while expressing breast milk. While it is well known that the prefrontal, parietal, and temporal cortices play important roles in the emotional and cognitive processing of maternal stimuli, knowledge about how these cortical areas function during breastfeeding is lacking. This study was designed to characterize EEG activity in the prefrontal and parietal cortices and the affective scores of primiparous breastfeeding mothers during two conditions of milk expression: breast milk expression and direct breastfeeding. Participants reported higher valence and arousal and a pleasant state during direct breastfeeding. In the direct breastfeeding condition, both prefrontal areas showed a higher absolute power (AP) of the slow bands, with a lower AP of the alpha band in the parietal cortex. A lower correlation between frontopolar and dorsolateral areas with a higher correlation between prefrontal and parietal cortices was obtained mainly in the right hemisphere. This EEG activity could be linked to an internal state of focused attention and, simultaneously, open monitoring of the environment that suggests an integration of the motive-emotional and cognitive processes necessary for adequate mother-baby interaction during direct breastfeeding.

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BACKGROUND: Cardiovascular diseases (CVDs) are the leading cause of women's mortality, linked to aging and reduced estrogen during menopause. Estrogen replacement therapy (ERT) is suggested for CVDs prevention. Yet, its timing initiation remains contentious. Thus, we aimed to evaluate the effect of early and late estrogen therapy on cardiac function and lipid metabolism in ovariectomized old female Wistar rats. METHODS: Fifty randomized female Wistar rats were included in 5 groups (n = 10, 18 months old): (1) Sham, (2) 10 weeks post ovariectomy (Ovx-10 w), (3) 10 weeks post Ovx + early estrogen replacement therapy (Ovx 10 w-early ERT), (4) 20 weeks post Ovx (Ovx-20 w) and (5) Ovx 20 w-late ERT. Three days (early ERT) or 10 weeks (late ERT) after surgery 17-ß estradiol was given (5 µg/kg/day), and 10 weeks after the start of ERT, we assessed cardiac function by echocardiography, electrocardiography, and cardiac catheterization. Estradiol, cholesterol, triglyceride (TG), high-density lipoprotein (HDL) and low-density lipoprotein (LDL) levels were determined. Cardiac histology was performed with Masson's staining. RESULTS: Ovariectomy (Ovx) increases left ventricle internal systolic diameter (0.4 vs 0.3 cm, *p = 0.020) and decreases shortening fraction (40 vs 54 %, *p = 0.030) regardless of therapy. ERT prevents the increase in left ventricle mass after 10 weeks post-Ovx and the ejection fractionreduction after 20 weeks. Lower P wave amplitudes (18.8 vs 24.2 ms, *p = 0.013) were found in the Ovx-20 w group. A longer duration of the QRS complex after 20 weeks post-Ovx with and without ERT was found (32.5 and 32.1 vs 28.3 ms, *p = 0.003; *p = 0.007). Diastolic blood pressure was higher 20 weeks post-Ovx (86 vs 76 mmHg, *p = 0.047), regardless of ERT. The left ventricle (LV) -dP/dt was decreased in Ovx groups without ERT (-750 vs -1320 mmHg, *p = 0.034). An increase in LV collagen deposition was found in the Ovx 10 w group vs Sham (9.58 vs 4.54 %, *p = 0.028). Early ERT avoids the increase in body weight, cholesterol and LDL caused by Ovx. CONCLUSIONS: Ovariectomy causes time-dependent alterations in lipid metabolism, morphology, electrical activity, and heart contractile function. Early but not late ERT prevents some of these effects.

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In the search for insects as biological control agents for the water primrose, the delphacid Pissonotusparaguayensis (Delphacidae) was found on Ludwigiagrandiflorasubsp.hexapetala (Onagraceae) in a wetland of Central East Argentina. The morphology of the unknown females (brachypterous and macropterous) and immature stages are described and illustrated. Adults and nymphs were collected in wetlands of Del Plata River Basin, from Buenos Aires to the northeastern part of Argentina. A rearing methodology was developed to perform biological studies. Both winged forms and structural features of the female genitalia are described for the first time at the genus level. Eggs and immature stages are described and keyed; fifth nymphal instars may be easily recognised by the yellowish colouration, blackish on dorsal of head, thorax and abdomen with conspicuous yellowish pits, ventrally only darkened on base of frons extended to lower level of eyes and dorsal surface of antennomeres I and II, and legs with distinctive black marks at femoro-tibial joint and apex. The geographical distribution is updated, expanding its range into Argentina, making Buenos Aires the southernmost limit of the genus in America. Biological information of the species is also reported here: life cycle, fecundity, oviposition behaviour, and host plant. Field observations showed that P.paraguayensis breeds, feeds, and causes damage to L.g.subsp.hexapetala. This delphacid presents a certain degree of specificity to the Ludwigia species in the Jussiaea section in host specificity tests. More studies are required to test this species as a potential biological control agent.

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BACKGROUND: Chitosan is a cheap, accessible, nontoxic, biocompatible, and biodegradable compound. Also, this polysaccharide possesses antibacterial and anti-inflammatory properties. Consequently, a wide range of chitosan applications in the dentistry field has been explored. This work aimed to conduct a systematic review to address the clinical efficacy of chitosan for the treatment of oral mucositis. MATERIAL AND METHODS: The design of the included studies were observational studies, randomized clinical trials (RCT), and non-randomized clinical trials (non-RCT), whereas, a series of cases, in vivo, and in vitro studies were excluded. The search was performed in PubMed, Web of Science, Scopus, Dentistry and Oral Sciences Source, and ClinicalTrials. Gray literature was searched at Google Scholar. Relevant data from all included studies were recorded. The risk of bias (using RoB 2) and the quality (using Grading of Recommendations Assessment, Development, and Evaluation, GRADE) assessments were carried out. RESULTS: From the 8413 records screened, 5 clinical trials fully met the eligibility criteria, which comprised a total of 192 participants suffering oral lesions and pain related to oral mucositis. 100% of the included studies exhibited a high risk of bias. The quality of the studies was between low and very low. CONCLUSIONS: The results of the included studies suggest that chitosan can diminish pain and improve the healing of ulcers in oral mucositis. However, there is no conclusive evidence of chitosan as a superior treatment for oral mucositis compared with other current therapies.

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Resumen Con la implementación de estrategias de cuidado perinatal, la tasa de transmisión vertical del virus de inmunodeficiencia humana (VIH) ha disminuido considerablemente en el mundo. A pesar de no mostrar cargas virales, los infantes expuestos al VIH no infectados (ENI) cursan en sus primeros meses de vida con mayores tasas de morbimortalidad. Esto se relaciona con enfermedades infecciosas por microorganismos oportunistas y menor respuesta a las vacunas en comparación con infantes sin exposición al virus, lo que sugiere alteraciones en su sistema inmunitario. En esta revisión abordamos diferentes evidencias de alteraciones en las respuestas inmunitarias innatas y adaptativas de infantes ENI que pudieran explicar esta disfuncionalidad inmunitaria. Adicionalmente, este conocimiento ayuda a entender cómo se desarrolla el sistema inmunitario desde los primeros momentos de gestación que servirán para encontrar alternativas de manejo y terapias para el bienestar de los infantes con esta condición.

Abstract With the implementation of perinatal care strategies, the rate of vertical transmission of human immunodeficiency virus (HIV) has decreased considerably worldwide. Despite the absence of viral loads, infants exposed to HIV not infected during gestation have higher morbidity and mortality rates. This is found to be related to infectious diseases by opportunistic microorganisms and lower response to vaccines in their first months of life compared to non-HIV exposed infants, suggesting alterations in their immune system. In this review we address different evidence of alterations in the innate and adaptive immune responses of HIV exposed infants that could explain their immune dysfunctionality. Additionally, this knowledge helps to understand how the immune system develops from the early stages of gestation and will serve to find management alternatives and therapies for the welfare of the infants with this condition.