Advances in surface design and biomedical applications of magnetic nanoparticles.

Despite significant efforts by scientists in the development of advanced nanotechnology materials for smart diagnosis devices and drug delivery systems, the success of clinical trials remains largely elusive. In order to address this biomedical challenge, magnetic nanoparticles (MNPs) have gained attention as a promising candidate due to their theranostic properties, which allow the simultaneous treatment and diagnosis of a disease. Moreover, MNPs have advantageous characteristics such as a larger surface area, high surface-to-volume ratio, enhanced mobility, mass transference and, more notably, easy manipulation under external magnetic fields. Besides, certain magnetic particle types based on the magnetite (Fe3O4) phase have already been FDA-approved, demonstrating biocompatible and low toxicity. Typically, surface modification and/or functional group conjugation are required to prevent oxidation and particle aggregation. A wide range of inorganic and organic molecules have been utilized to coat the surface of MNPs, including surfactants, antibodies, synthetic and natural polymers, silica, metals, and various other substances. Furthermore, various strategies have been developed for the synthesis and surface functionalization of MNPs to enhance their colloidal stability, biocompatibility, good response to an external magnetic field, etc. Both uncoated MNPs and those coated with inorganic and organic compounds exhibit versatility, making them suitable for a range of applications such as drug delivery systems (DDS), magnetic hyperthermia, fluorescent biological labels, biodetection and magnetic resonance imaging (MRI). Thus, this review provides an update of recently published MNPs works, providing a current discussion regarding their strategies of synthesis and surface modifications, biomedical applications, and perspectives.

Male reproductive traits are differentially affected by dietary macronutrient balance but unrelated to adiposity.

Dietary factors influence male reproductive function in both experimental and epidemiological studies. However, there are currently no specific dietary guidelines for male preconception health. Here, we use the Nutritional Geometry framework to examine the effects of dietary macronutrient balance on reproductive traits in C57BL/6 J male mice. Dietary effects are observed in a range of morphological, testicular and spermatozoa traits, although the relative influence of protein, fat, carbohydrate, and their interactions differ depending on the trait being examined. Interestingly, dietary fat has a positive influence on sperm motility and antioxidant capacity, differing to typical high fat diet studies where calorie content is not controlled for. Moreover, body adiposity is not significantly correlated with any of the reproductive traits measured in this study. These results demonstrate the importance of macronutrient balance and calorie intake on reproductive function and support the need to develop specific, targeted, preconception dietary guidelines for males.

Increased H2O2 levels and p53 stabilization lead to mitochondrial dysfunction in XPC-deficient cells.

XPC deficiency is associated with mitochondrial dysfunction, increased mitochondrial H2O2 production and sensitivity to the Complex III inhibitor antimycin A (AA), through a yet unclear mechanism. We found an imbalanced expression of several proteins that participate in important mitochondrial function and increased expression and phosphorylation of the tumor suppressor p53 in Xeroderma pigmentosum complementation group C (XP-C) (XPC-null) cells compared with an isogenic line corrected in locus with wild-type XPC (XPC-wt). Interestingly, inhibition of p53 nuclear import reversed the overexpression of mitochondrial proteins, whereas AA treatment increased p53 expression more strongly in the XP-C cells. However, inhibition of p53 substantially increased XP-C cellular sensitivity to AA treatment, suggesting that p53 is a critical factor mediating the cellular response to mitochondrial stress. On the other hand, treatment with the antioxidant N-acetylcysteine increased glutathione concentration and decreased basal H2O2 production, p53 levels and sensitivity to AA treatment in the XPC-null back to the levels found in XPC-wt cells. Thus, the results suggest a critical role for mitochondrially generated H2O2 in the regulation of p53 expression, which in turn modulates XP-C sensitivity to agents that cause mitochondrial stress.

The importance of early diagnosis and treatment of incidental tension pneumothorax during robotic assisted laparoscopy for diaphragmatic endometriosis: a report of two cases.

We describe two cases of diaphragmatic endometriosis treated using the robotic assisted laparoscopic approach, in which an incidental tension pneumothorax occurred during the initial inspection and assessment of diaphragmatic lesions. We demonstrate the importance of early diagnosis of this complication and report successful resolution using the thoracic drainage technique. In case one, after the pneumoperitoneum was installed, during the cavity assessment and inspection, small endometriotic lesions were observed in the tendon portion of the diaphragmatic surface. We observed a sudden increase in maximum airway pressures and a reduction in tidal volume, associated with arterial hypotension and hemodynamic instability and bulging of the diaphragm, which led to the diagnosis of a tension pneumothorax. In case two, diaphragmatic endometriotic lesions were also observed after hepatic mobilisation and following visualisation of the endometriotic lesions, an abrupt decrease in the capnography values was observed, consistent with hypertensive pneumothorax. In both cases, even after deflation of the abdominal cavity, hemodynamic instability persisted. We treated both cases with thoracic drainage, which immediately normalised respiratory parameters and resulted in hemodynamic stabilisation, and the surgical procedures were continued. During laparoscopic procedures for the treatment of diaphragmatic endometriosis, the endometriotic lesions can behave as communication hole in the tendon portion of the diaphragmatic surface and the changes in ventilatory patterns and haemodynamic instability should alert the medical team to the development of an incidental tension pneumothorax. The early identification of this complication in both cases allowed rapid intervention for chest drainage and allowed the surgical procedure to continue.

Nivel de conocimiento de Sífilis en adolescentes de dos Instituciones Educativas del distrito de Buenaventura / Level of knowledge of Syphilis in adolescents of two Educational Institutions of the Buenaventura district

Objetivo: Establecer el nivel de conocimiento de sífilis en adolescentes de dos Instituciones Educativas del distrito de Buenaventura de grados: noveno, décimo y once. Material y métodos: Estudio descriptivo de corte transversal en jóvenes entre 12 y 18 años; muestra a conveniencia de 420 estudiantes. Se aplicó una encuesta anónima dividida en 5 secciones. Se determinaron características sociodemográficas, hábitos, vida sexual y conocimiento sobre ITS. Resultados: 91% manifestó conocer sobre las ITS; 22,4% expresó conocer los signos y síntomas. 3,1& presentó diagnóstico de ITS; no reportaron casos de sífilis; 51,9% manifestó conocer la sífilis; el 10% expresó conocer signos y síntomas. 16% manifestó conocer mecanismo de prevención. 4% de los estudiantes tiene un buen nivel de conocimiento sobre sífilis. Sobre actividad sexual, 58,7% había iniciado vida sexual, 28% tuvo su primer encuentro a los 11 años o menos, siendo mayormente de género masculino. 33,8% habían tenido 1 pareja sexual, seguido de 23,8% con 6 o más parejas sexuales. El análisis de conocimiento sobre sífilis según institución educativa evidenció que el 8,9% y el 3% de los estudiantes tenía un nivel bueno de conocimiento, en la institución rural y urbana respectivamente. Al evaluar el conocimiento sobre ETS, se encontró que el 85% y 96% de estudiantes en zona rural y urbana respectivamente afirman tener conocimiento; sobre la sintomatología, 21% y 23 % es conocedor de esta, en área rural y urbana respectivamente. Conclusiones: Un alto porcentaje de estudiantes encuestados tienen un bajo nivel de conocimiento sobre sífilis; las mayores falencias se presentan en manifestaciones clínicas, la prevención y la cura de dicha enfermedad; aunque los adolescentes tienen múltiples fuentes de conocimiento, dicha información es deficiente, especialmente la transmitida por los padres y la pareja.

Objective: To establish the level of knowledge about syphilis in adolescents of two Educational Institutions in the district of Buenaventura of the ninth, tenth and eleventh grades. Material and methods: Descriptive cross-sectional study in young people between 12 and 18 years; convenience sample of 420 students. An anonymous survey divided into five sections was applied. Sociodemographic characteristics, habits, sexual life, and knowledge about STIs were determined. Results: 91% said they know about STIs, and 22.4% said they knowing the signs and symptoms. STI diagnoses were presented in 3.1%; not report syphilis cases. 51.9% said that knew about syphilis, 10% said they know signs and symptoms. 16% said they knew about mechanism prevention. 4% of students have a good level of knowledge about syphilis. About sexual activity 58.7% had started sexual life, 28% had their first encounter at age 11 or less, they were principally male. 33.8% had one sexual partner, followed by 23.8% with six or more sexual partners. Institutional Analysis showed that 8.9% (rural) and 3% (urban) of the students, were at a good level of knowledge. When evaluating knowledge about STDs, it was found that 85% (urban) and 96% (rural) students say they know, however, when inquiring about the symptoms, in rural and urban areas, 21 % and 23% respectively are aware of it. Conclusions: The highest percentage of students surveyed has a bad level of knowledge about syphilis, where the highest % was in clinical manifestations, the prevention, and cure of said disease; although adolescents have multiple sources of knowledge, this information is deficient, especially that shared by the parents and the couple.

Changes in behavioural parameters, oxidative stress and neurotrophins in the brain of adult offspring induced to an animal model of schizophrenia: The effects of FA deficient or FA supplemented diet during the neurodevelopmental phase.

A deficiency of maternal folic acid (FA) can compromise the function and development of the brain, and may produce a susceptibility to diseases such as schizophrenia (SZ) in the later life of offspring. The aim of this study was to evaluate the effects of both FA deficient and FA supplemented diets during gestation and lactation on behavioural parameters, the markers of oxidative stress and neurotrophic factors in adult offspring which had been subjected to an animal model of SZ. Female mother rats (Dam's) were separated into experimental maternal groups, which began receiving a special diet (food) consisting of the AIN-93 diet, a control diet, or an FA deficient diet during the periods of pregnancy and lactation. Dam's receiving the control diet were further subdivided into four groups: one group received only control diet, while three groups to receive supplementation with FA at different doses (5, 10 and 50 mg/kg). Adult offspring bred from the Dam's were divided into ten groups for induction of the animal model of SZ through the administration of ketamine (Ket) (25 mg/kg). After the last administration of the drug, the animals were subjected to the behavioural tests and were then euthanized. The frontal cortex (FC) and hippocampus (Hip) were then dissected for later biochemical analysis. Our data demonstrates that Ket induced the model of SZ by altering the behavioural parameters (e.g. hyperlocomotion, social impairment, deficits in the sensory-motor profile and memory damage in the adult animals); and also caused changes in the parameters of oxidative stress (lipid hydroperoxide - LPO; 8-isoprostane - 8-ISO; 4-hydroxynonenal - 4-HNE; protein carbonyl content; superoxide dismutase - SOD and catalase - CAT) as well as in the levels of neurotrophic factors (brain-derived neurotrophic factor - BDNF and nerve growth factor - NGF) particularly within the FC of adult offspring. A deficiency in maternal FA, alone or in combination with ket, was able to induce hyperlocomotion and social impairment in the offspring with increased levels of lipid and protein damage (LPO, 8-ISO, 4-HNE, carbonylation of protein) within the FC, increased activity of antioxidant enzymes (SOD and CAT) in both of the brain structures studied, and also reduced the levels of neurotrophins (BDNF and NGF), particularly within the Hip of the adult offspring. Supplementation of FA (5, 10 and 50 mg/kg) to the Dam's was mostly able to prevent the cognitive damage which was induced by Ket in the adult animals. FA (10 and 50 mg/kg) attenuated the action of Ket in the animals in relation to the biochemical parameters, proving the possible neuroprotective effect of FA in the adulthood of offspring that were subjected to the animal model of SZ. Our study indicates that the intake of maternal FA during pregnancy and lactation plays an important role, particularly in the regulation of markers of oxidative stress and neurotrophins.

Fast ultrasound assisted synthesis of chitosan-based magnetite nanocomposites as a modified electrode sensor.

Chitosan-based magnetite nanocomposites were synthesized using a versatile ultrasound assisted in situ method involving one quick step. This synthetic route approach results in the formation of spheroidal nanoparticles (Fe3O4) with average diameter between 10 and 24nm, which were found to be superparamagnetic with saturation magnetization (Ms) ranges from 32-57emug(-1), depending on the concentration. The incorporation of Fe3O4 into chitosan matrix was also confirmed by FTIR and TG techniques. This hybrid nanocomposite has the potential application as electrochemical sensors, since the electrochemical signal was excepitionally stable. In addition, the in situ strategy proposed in this work allowed us to synthesize the nanocomposite system in a short time, around 2min of time-consuming, showing great potential to replace convencional methods. Herein, the procedure will permit a further diversity of applications into nanocomposite materials engineering.

n-3 polyunsaturated fatty acid supplementation reduces insulin resistance in hepatitis C virus infected patients: a randomised controlled trial.

BACKGROUND: Insulin resistance promotes liver disease progression and may be associated with a lower response rate in treated hepatitis C virus (HCV) infected patients. n-3 polyunsaturated fatty acid (PUFA) supplementation may reduce insulin resistance. The present study aimed to evaluate the effect of n-3 PUFA supplementation on insulin resistance in these patients. METHODS: In a randomised, double-blind clinical trial, 154 patients were screened. After applying inclusion criteria, 52 patients [homeostasis model assessment index of insulin resistance (HOMA-IR ≥2.5)] were randomly divided into two groups: n-3 PUFA (n = 25/6000 mg day(-1) of fish oil) or control (n = 27/6000 mg day(-1) of soybean oil). Both groups were supplemented for 12 weeks and underwent monthly nutritional consultation. Biochemical tests were performed at baseline and after intervention. Statistical analysis was performed using the Wilcoxon Mann-Whitney test for comparisons and the Wilcoxon test for paired data. Statistical package r, version 3.02 (The R Project for Statistical Computing) was used and P < 0.05 (two-tailed) was considered statistically significant. RESULTS: Comparisons between groups showed that n-3 PUFA supplementation was more effective than the control for reducing HOMA-IR (P = 0.015) and serum insulin (P = 0.016). The n-3 PUFA group not only showed a significant reduction in HOMA-IR 3.8 (3.2-5.0) versus 2.4 (1.8-3.3) (P = 0.002); serum insulin 17.1 (13.8-20.6) µIU mL(-1) versus 10.9 (8.6-14.6) µIU mL(-1) (P = 0.001); and glycated haemoglobin 5.4% (5.0-5.7%) versus 5.1% (4.8-5.6%) (P = 0.011), but also presented an increase in interleukin-1 97.5 (0.0-199.8) pg mL(-1) versus 192.4 (102.2-266.8) pg mL(-1) (P = 0.003) and tumour necrosis factor 121.2 (0.0-171.3) pg mL(-1) versus 185.7 (98.0-246.9) pg mL(-1) (P = 0.003). CONCLUSIONS: n-3 PUFA supplementation reduces insulin resistance in genotype 1 HCV infected patients.

Colour stability of denture teeth submitted to different cleaning protocols and accelerated artificial aging.

Acrylic resin is widely used for artificial teeth manufacturing due to several important characteristics; however, this material do not present acceptable colour stability over the course of time. This study evaluated the effect of different cleaning protocols and accelerated artificial aging on colour stability of denture teeth made of acrylic resin. Sixty denture teeth in dark and light shades were used, and separated according to the treatment to which they were submitted. Results demonstrated that colour stability of artificial teeth is influenced by the cleaning solution and artificial aging, being dark teeth more susceptible to colour alteration than lighter ones.

Possible molecular mechanisms soy-mediated in preventing and treating nonalcoholic fatty liver disease.

The aim of this review is to describe the molecular mechanisms of nonalcoholic fatty liver disease (NAFLD) and to present evidence regarding the mechanisms of soy-mediated therapeutic activity in preventing and treating NAFLD. NAFLD is induced by multiple metabolic pathways, including an increase in the release of fatty acids from the adipose tissue (lipolysis), insulin resistance (IR), and an increase in "de novo" fatty acid synthesis. Furthermore, NAFLD is correlated with a decrease in liver ß-oxidation, an increase in oxygen free radical production, and an increase in pro-inflammatory cytokine production, which leads to an increase in liver fat and, subsequently, to tissue damage. The bioactive compounds in soy can prevent and treat NAFLD by modulating lipid metabolism and regulating the expression of related transcription factors. Soy intake decreases the expression of sterol regulatory-element binding protein-lc (SREBP-1) and increases the expression of SREBP-2, which are transcription factors associated with the regulation of hepatic lipogenesis and reduction of cholesterol synthesis and absorption in the liver, respectively. Besides, interactions between soy components, such as standard amino acids, polyunsaturated fat, and the isoflavonoid-enriched fraction, are believed to improve fatty acid oxidation in the liver parenchyma by increasing the expression of peroxisome proliferator-activated receptor α (PPARα)-regulated genes, thus decreasing lipid accumulation in the liver. Therefore, including soy-derived foods in the diet as a therapeutic tool for patients with NAFLD might improve their clinical evolution.

Effects of creatine supplementation on glucose tolerance and insulin sensitivity in sedentary healthy males undergoing aerobic training.

Recent findings have indicated that creatine supplementation may affect glucose metabolism. This study aimed to examine the effects of creatine supplementation, combined with aerobic training, on glucose tolerance in sedentary healthy male. Subjects (n = 22) were randomly divided in two groups and were allocated to receive treatment with either creatine (CT) ( approximately 10 g . day over three months) or placebo (PT) (dextrose). Administration of treatments was double blind. Both groups underwent moderate aerobic training. An oral glucose tolerance test (OGTT) was performed and both fasting plasma insulin and the homeostasis model assessment (HOMA) index were assessed at the start, and after four, eight and twelve weeks. CT demonstrated significant decrease in OGTT area under the curve compared to PT (P = 0.034). There were no differences between groups or over time in fasting insulin or HOMA. The results suggest that creatine supplementation, combined with aerobic training, can improve glucose tolerance but does not affect insulin sensitivity, and may warrant further investigation with diabetic subjects.

Analgesic and anti-inflammatory dose-response relationship of 7.5 and 15 mg meloxicam after lower third molar removal: a double-blind, randomized, crossover study.

Fifty patients were scheduled to undergo removal of symmetrically positioned lower third molars in two separate appointments. Meloxicam 7.5 or 15 mg was once daily administered in a double-blind, randomized and crossover manner after the surgery for 4 days. Objective and subjective parameters were recorded for comparison of postoperative courses. Patients treated with 7.5mg meloxicam who underwent osteotomy reported higher pain scores at 1.5, 3, 4, 10, 12 and 16 h (P<0.05) and ingested a greater amount of rescue analgesic medication (P<0.05) than those who did not require osteotomy. A higher percentage of patients who underwent osteotomy medicated with 7.5mg meloxicam needed rescue medication as compared to those who did not require osteotomy (P<0.05). There was a similar mouth opening at suture removal compared with preoperative values for both doses (P>0.05). There were no significant differences concerning swelling observed on the 2nd or 7th postoperative days in comparison with baseline (P>0.05) between the two doses. Pain, trismus and swelling after lower third molar removal not requiring osteotomy can be successfully controlled by a dose regimen of 7.5mg meloxicam once daily. For more aggressive extractions 15 mg meloxicam is advisable.

Relevancia inmunológica y biomédica del antígeno Tn / Immunological and biomedical relevance of the Tn antigen

El antígeno Tn es una estructura glico-aminoacídica (GalNAc-O-Ser/Thr) que en las células humanas normales se encuentra enmascarada por la elongación de las cadenas carbohidratas de tipo O. Algunas células anormales expresan Tn cuando esta elongación no ocurre. Tn fue descubierto como el antígeno responsable de la poliaglutinación de los eritrocitos obtenidos de un paciente con una anemia hemolítica poco frecuente (síndrome Tn), siendo extensamente estudiado a partir de su caracterización como una de las estructuras más específicas asociadas a carcinomas humanos. El interés de Tn en la biología tumoral se debe a que constituye una molécula de reconocimiento, que participa en diferentes interacciones celulares (por ejemplo, involucrada en el proceso metastásico). Algunos glicopéptidos Tn pueden unirse a proteínas del complejo mayor de histocompatibilidad e inducir activación de linfocitos T. Recientemente se comprobó la amplia distribución de Tn en parásitos helmintos, lo que puede abrir nuevos horizontes en el estudio de las interacciones parásito-huésped. La expresión de Tn en las células sanguíneas de los pacientes con el síndrome Tn se debe a la adquisición de una represión estable del gen que codifica para la glicosiltransferasa "core" 1 3Gal-T. Sin embargo, las bases moleculares de la expresión de Tn en las células cancerosas son poco conocidas. Dentro de los posibles mecanismos que pueden estar involucrados se encuentran la desregulación en la expresión de las glicosiltransferasas que catalizan las etapas iniciales de la O-glicosilación y/o a la desregulación en la expresión de apomucinas. Han sido caracterizadas las interacciones entre Tn y diferentes proteínas, observándose que los anticuerpos requieren habitualmente epítopos más complejos que la estructura GalNAc-O-Ser/Thr como, por ejemplo, la participación de otros aminoácidos en el determinante antigénico o la existencia de sitios con alta densidad de residuos Tn. El desarrollo de respuestas inmunes contra residuos Tn organizados en "clusters" ha sido efectiva en protocolos de inmunoterapia en modelos animales, representando una estrategia de potencial utilidad para el desarrollo de vacunas anti-tumorales (AU)

Prevalence of anti-Leishmania donovani antibody among Brazilian blood donors and multiply transfused hemodialysis patients.

The prevalence of anti-Leishmania donovani antibodies was investigated in 1,500 Brazilian blood donors and multiply transfused hemodialysis patients. Sera were tested using the fucose-mannose ligand (FML) ELISA, which was shown to have 100% sensitivity and 96% specificity for kala-azar. Among 1,194 volunteer blood donors, seroreactivity was 9%, increasing to 25% in a periurban kala-azar focus. However, higher positivity (37%) was found in multiply transfused hemodialysis patients from Natal, where kala-azar is constantly present in low numbers (endemic), with sporadic outbreaks in localized regions (endemic and epidemic). Risk factors included blood transfusion, which was significantly associated with the presence of anti-Leishmania antibodies (chi2 = 8.567, P < 0.005), but did not include potential exposure to sandfly bites (chi2 = 0.033, P > 0.1). The prevalence significantly decreased to 7% in hemodialysis patients from Rio de Janeiro, where kala-azar is only occasionally seen, and was 0% in patients undergoing continuous ambulatorial peritoneal dialysis. The prospective analysis of 27 FML-seroreactive donors from Natal revealed amastigotes of Leishmania in the bone marrow of one subject while four had clinical complaints, including splenomegaly and hepatosplenomegaly. Our results point to the need for control of blood transfusion as a possible route for transmission of kala-azar in endemic areas.

Factores que justifican el control del tuberculoso no confirmado / Factors justifying the control of non-confirmed patients

Cuando se encuentran imágenes radiológicas con baciloscopía negativa, éstas deben ser estudiadas minuciosamente porque constituyen una información epidemiológica de afección pulmonar pero no de enfermedad tuberculosa. Imágenes precoces y antiguas son denominaciones de tiempo; mínima, moderada y avanzada indican extensión; cavitarias, nodulares y fibrosas se basan en la Anatomía patológica, ayudada con la broncoscopía de fibra óptica. La agravación sintomatológica ó radiológica puede constituir una alerta, pero no un criterio de fracaso. Muy buenos resultados de tratamiento antituberculosos se han dado en paciente a quienes se les aplica sistemáticamente y no cuando se lo hace en forma selectiva, esperando la agravación de los síntomas clínicos, radiológicos ó bacteriológicos, reduciéndose del 74% a un 2% las recaídas en pacientes estudiados durante cinco años de seguimiento

Factores que justifican el control del tuberculoso no confirmado / Factors justifying the control of non-confirmed patients

Cuando se encuentran imágenes radiológicas con baciloscopía negativa, éstas deben ser estudiadas minuciosamente porque constituyen una información epidemiológica de afección pulmonar pero no de enfermedad tuberculosa. Imágenes precoces y antiguas son denominaciones de tiempo; mínima, moderada y avanzada indican extensión; cavitarias, nodulares y fibrosas se basan en la Anatomía patológica, ayudada con la broncoscopía de fibra óptica. La agravación sintomatológica ó radiológica puede constituir una alerta, pero no un criterio de fracaso. Muy buenos resultados de tratamiento antituberculosos se han dado en paciente a quienes se les aplica sistemáticamente y no cuando se lo hace en forma selectiva, esperando la agravación de los síntomas clínicos, radiológicos ó bacteriológicos, reduciéndose del 74% a un 2% las recaídas en pacientes estudiados durante cinco años de seguimiento (AU)