A review of endophenotypes in schizophrenia and autism: The next phase for understanding genetic etiologies.

Many psychiatric disorders are caused by multiple genes and multiple environmental factors, making the identification of specific genetic risk factors for these disorders difficult. Endophenotypes are behaviors or characteristics that are intermediate between the genotype and a phenotype of interest. Because they are more directly related to the gene action than is the endpoint disorder, they may be useful in the identification of specific genes related to psychiatric disorders and the classification of disorders or traits that share an underlying genetic etiology. We discuss genetic and endophenotype research on schizophrenia and autism spectrum disorder (ASD) in this review. Some of the psychophysiological endophenotypes that have been studied for schizophrenia include prepulse inhibition of the startle response, the antisaccadic task assessing frontal lobe function, inhibition of the P50 event-related potential (ERP), and other auditory ERP measures. Potential ASD endophenotypes include theory of mind, language skills (specifically, age at first spoken word and first spoken phrase), social skills, and certain brain functions, such as asynchronization of neural activity and brain responses to emotional faces. Because the link between genes and specific psychiatric disorders is difficult to determine, identification of endophenotypes is useful for beginning the search to identify specific genes that affect these disorders.

RalA is overactivated in medulloblastoma.

Medulloblastoma (MDB) represents a major form of malignant brain tumors in the pediatric population. A vast spectrum of research on MDB has advanced our understanding of the underlying mechanism, however, a significant need still exists to develop novel therapeutics on the basis of gaining new knowledge about the characteristics of cell signaling networks involved. The Ras signaling pathway, one of the most important proto-oncogenic pathways involved in human cancers, has been shown to be involved in the development of neurological malignancies. We have studied an important effector down-stream of Ras, namely RalA (Ras-Like), for the first time and revealed overactivation of RalA in MDB. Affinity precipitation analysis of active RalA (RalA-GTP) in eight MDB cell lines (DAOY, RES256, RES262, UW228-1, UW426, UW473, D283 and D425) revealed that the majority contained elevated levels of active RalA (RalA-GTP) as compared with fetal cerebellar tissue as a normal control. Additionally, total RalA levels were shown to be elevated in 20 MDB patient samples as compared to normal brain tissue. The overall expression of RalA, however, was comparable in cancerous and normal samples. Other important effectors of RalA pathway including RalA binding protein-1 (RalBP1) and protein phosphatase A (PP2A) down-stream of Ral and Aurora kinase A (AKA) as an upstream RalA activator were also investigated in MDB. Considering the lack of specific inhibitors for RalA, we used gene specific silencing in order to inhibit RalA expression. Using a lentivirus expressing anti-RalA shRNA we successfully inhibited RalA expression in MDB and observed a significant reduction in proliferation and invasiveness. Similar results were observed using inhibitors of AKA and geranyl-geranyl transferase (non-specific inhibitors of RalA signaling) in terms of loss of in vivo tumorigenicity in heterotopic nude mouse model. Finally, once tested in cells expressing CD133 (a marker for MDB cancer stem cells), higher levels of RalA activation was observed. These data not only bring RalA to light as an important contributor to the malignant phenotype of MDB but introduces this pathway as a novel target in the treatment of this malignancy.

Overactivation of Ras signaling pathway in CD133+ MPNST cells.

Cancer stem cells (CSCs) are believed to be the regenerative pool of cells responsible for repopulating tumors. Gaining knowledge about the signaling characteristics of CSCs is important for understanding the biology of tumors and developing novel anti-cancer therapies. We have identified a subpopulation of cells positive for CD133 (a CSC marker) from human primary malignant peripheral nerve sheath tumor (MPNST) cells which were absent in non-malignant Schwann cells. CD133 was also found to be expressed in human tissue samples and mouse MPNST cells. CD133+ cells were capable of forming spheres in non-adherent/serum-free conditions. The activation levels of Ras and its downstream effectors such as ERK, JNK, PI3K, p38K, and RalA were significantly increased in this population. Moreover, the CD133+ cells showed enhanced invasiveness which was linked to the increased expression of ß-Catenin and Snail, two important proteins involved in the epithelial to mesenchymal transition, and Paxilin, a focal adhesion protein. Among other important characteristics of the CD133+ population, endoplasmic reticulum stress marker IRE1α was decreased, implying the potential sensitivity of CD133+ to the accumulation of unfolded proteins. Apoptotic indicators seemed to be unchanged in CD133+ cells when compared to the wild (unsorted) cells. Finally, in order to test the possibility of targeting CD133+ MPNST cells with Ras pathway pharmacological inhibitors, we exposed these cells to an ERK inhibitor. The wild population was more sensitive to inhibition of proliferation by this inhibitor as compared with the CD133+ cells supporting previous studies observing enhanced chemoresistance of these cells.

Struggling in pandemic times: Migrant women's virtual political organization during the COVID-19 crisis in Spain.

During the COVID-19 pandemic in Spain, the lockdowns brought about the loss of labour and social rights for many migrant women working in highly informal employment sectors. Drawing on digital ethnography, this article examines the role of migrant women in political mobilization within migrant associations during 2020 in Spain, when online interactions assumed primary importance. First, it shows how migrant organizations create bricolage by combining economic, social, cultural and political resources to organize migrants in Spain during COVID-19 within the digital space. Second, the article highlights how the reactions of the migrant population to the pandemic in Spain represent an act of disruption led mainly by women, within the dynamics of social conflict and political activism that characterize migratory processes. This analysis displays as well the crucial role played by care relationships in these contexts of crises.

[Quality of the diet of women with severe and morbid obesity undergoing gastric bypass and sleeve gastrectomy]. / Calidad de la alimentación de mujeres con obesidad severa y mórbida sometidas a bypass gastrico y gastrectomia vertical en manga.

The objective of this study was to evaluate the changes of dietary intake and quality of the diet in patients undergoing gastric bypass and sleeve surgery. In 36 women with severe and morbid obesity it was assessed their nutrient intakes and dietary quality before and 6 months after bariatric surgery through three-day food records. Vitamin and mineral intakes from supplements were strictly controlled. Energy and nutrient intakes were significantly decreased 6 months after surgery bypass compared to the pre-surgery period with the exceptions of calcium and vitamin C. No differences were observed between groups. The Dietary quality index was also similar in both groups. Dietary intakes of calcium, iron, zinc, copper, folic acid, vitamin C, and vitamin E were below 100% of adequacy from at the 6th month after the surgery. Nevertheless, by considering both diet and supplements supply, nutrient adequacy of all but calcium and folic acid was above 100% in both groups. Gastric bypass patients presented greater values. In conclusion, these patients present an important reduction of their energy and nutrient intakes, with no major impact of the type of surgery. Supplement characteristics are crucial to cover nutritional needs.

Kinetics of regulated actin transitions measured by probes on tropomyosin.

Changes in the muscle regulatory protein complex, troponin, are important for modulation of activity and may occur as a result of disease-causing mutations. Both increases and decreases in the rate of ATP hydrolysis by myosin may occur as dictated by changes in the distribution of actin-tropomyosin-troponin among its different states. It is important to measure the rates of transition among these states to study physiological adaptation and disease processes. We show here that acrylodan or pyrene probes on tropomyosin can be used to monitor the transition from active to intermediate and inactive states of actin-tropomyosin-troponin. Transitions measured in the absence of calcium had two phases, as previously reported for some other probes on troponin and actin. The first step was a rapid equilibrium that favored the formation of the intermediate state and had an apparent rate constant less than that of S1-ATP dissociation. The second fluorescence transition was slower, with an apparent constant that increased from approximately 5 to 80/s over a range of 1-37 degrees C. Only the initial rapid transition was seen in the presence of saturating calcium. The acrylodan probe had the advantage of yielding a larger signal than the pyrene probe. Furthermore, the acrylodan signal decreased in going from the active state to the intermediate state, and then increased upon going to the inactive state.

Changes in resting energy expenditure and body composition after weight loss following Roux-en-Y gastric bypass.

BACKGROUND: The objective of this study was to evaluate changes in resting energy expenditure (REE), body composition and metabolic parameters, and to investigate predictors of the results in seriously obese patients after Roux-en-Y gastric bypass (RYGBP). METHODS: 31 patients (BMI 44.4 +/- 4.8 kg/m2; 27 female, 4 male; 37.3 +/- 11.1 y) were evaluated at baseline and 6 months after RYGBP. Weight, REE, waist circumference (WC), fat mass (FM) and fat-free mass (FFM), physical activity, food intake, fasting glucose (GLU), insulin (INS), HOMA-IR and lipid concentrations were measured. RESULTS: At 6 months, percentage of weight loss (%WL) was 29.0 +/- 4.4% and percentage of excess weight loss was (%EWL) 59.7 +/- 12.3%. FM loss corresponded to 77.1 +/- 12.2% of the weight loss. REE decreased from 33.4 +/- 4.1 to 30.1 +/- 2.6 kcal/kg FFM (P<0.05). Significant decreases (P<0.001) were observed in GLU, INS, HOMA-IR, LDL-cholesterol and triglycerides. %EWL was correlated with baseline INS (r=0.44; P=0.014), baseline HOMA (r=0.43; P=0.017), change in %FM (r=0.67; P<0.001) and change in WC (r=0.5; P<0.01). Decrease in REE/FFM (%) was positively correlated with baseline REE/FFM% (r=0.51; P<0.005) and change in %FM (r=0.69; P<0.001). Initial REE/FFM, baseline energy balance and FM change explain 90% of REE/FFM decrease. CONCLUSION: RYGBP was an effective procedure to induce significant weight loss, fat mass loss and improvement in metabolic parameters in the short term. Metabolic adaptation was not related to FFM wasting but to a higher baseline REE. Fasting hyperinsulinemia was the best single predictor of weight loss after RYGBP.

Distribution of the H+/peptide transporter PepT1 in human intestine: up-regulated expression in the colonic mucosa of patients with short-bowel syndrome.

BACKGROUND: Intestinal adaptation after massive bowel resection in animal models is characterized by increased gut-mucosal growth and expression of nutrient transporters. Few data about these indexes exist in humans with short-bowel syndrome (SBS). OBJECTIVE: The objective was to compare small-bowel and colonic mucosal growth and expression of the peptide transporter PepT1 in adults with or without SBS. DESIGN: Mucosal biopsy specimens were obtained from the small bowel and colon of 33 control subjects with intact intestine and from 13 SBS patients dependent on parenteral nutrition because of chronic malabsorption. Gut-mucosal crypt depth, villus height, and villus width were measured, and expression of PepT1 was determined by Northern blotting, in situ hybridization, and immunohistochemistry. RESULTS: The indexes of small-bowel and colonic mucosal growth were not significantly different between the 2 groups. PepT1 expression was high in the apical region of duodenal, jejunal, and ileal villus epithelial cells; low in absorptive colonocytes; and not significantly different in the distal small intestine of the 2 groups. However, the abundance of PepT1 mRNA in the colon of SBS patients was more than 5-fold that in control subjects (P < 0.01). CONCLUSIONS: Gut adaptation in SBS patients does not appear to involve an increase in gut-mucosal crypt depth or villus size. PepT1 is abundant along the small-bowel brush border in humans; expression in the colon indicates that the large intestine has a mechanism for luminal di- and tripeptide transport. Up-regulation of colonic PepT1 in SBS may adaptively improve accrual of malabsorbed di- and tripeptides, independent of changes in the mucosal surface area.

Indicaciones para el uso del catéter venoso central y el tiempo de colocación en los pacientes hospitalizados en el servicio de medicina interna del hospital Dr. Miguel Pérez Carreño / Indications for the use of the central venous catheter and the time of its use in the patients hospitalized in the internal medicine service of the Dr. Miguel Pérez Carreño hospital

La inserción del catéter venoso central (CVC) ha significado un gran avance en la medicina moderna y su uso generalizado ha permitido el desarrollo de nuevas técnicas diagnósticas y tratamientos especializados. En este estudio se dan a conocer las indicaciones presentes al momento de colocar el catéter venoso central y el tiempo de colocación en los pacientes. Métodos: La investigación fue de tipo retrospectivo, descriptivo y de corte transversal, con un diseño de investigación no experimental y tuvo la finalidad de conocer, en forma directa, la realidad de la problemática. Las unidades de observación fueron(188) historias clínicas de los pacientes que ingresaron en el servicio de medicina interna en el hospital Miguel Pérez Carreño en el periodo comprendido entre enero y abril de 2017. Resultados: El 68% de la indicación del catéter venoso central es para la medición de la presión venosa central (PVC) y control de líquidos, mientras que en el 32% la indicación fue por administración de fármacos. El tiempo de colocación tuvo un predominio del 61% de los pacientes que utilizaron el catéter venoso central durante 1 a 3 semanas, en segundo lugar, el 36% utilizo el catéter por unos días, solo un 3% amerito el uso del catéter venoso central durante 1 mes. Conclusiones: La mayoría de los pacientes estudiados tuvieron como principal indicación de CVC para control de líquido y medición de presión venosa central. Con una duración de 1 a 3 semanas(AU)

The insertion of the central venous catheter (CVC) has meant a great advance in modern medicine and its widespread use has allowed the development of new diagnostic techniques and specialized treatments. In this study we present the indications present at the moment of placing the central venous catheter and the time of use in patients. Methods: The research was of a retrospective, descriptive and cross-sectional type, with a non-experimental research design and aimed to know, in a direct way, the reality of the problem. The units of observation were (188) clinical records of patients admitted to the internal medicine service in the hospital Miguel Pérez Carreño in the period between January and April 2017. Results: 68% of the indication of the central venous catheter is for the measurement of central venous pressure (CVP) and fluid control, while in 32% the indication was for drug administration. The time of use had a predominance of 61% of patients who used the central venous catheter for 1 to 3 weeks, secondly, 36% used the catheter for a few days, only 3% required the use of the central venous catheter for 1 month. Conclusions: The majority of patients studied had CVC as main indication for fluid control and central venous pressure measurement. With a duration of 1 to 3 weeks(AU)

Microorganismos que colonizan los catéteres venosos centrales de los pacientes hospitalizados en el servicio de medicina intern / Microorganisms that colonize the central venous catheters of patients hospitalized in the internal medicine service of the Dr. Miguel Pérez Carreño hospital

La utilización de catéter venoso central produce, en ocasiones, infecciones de tipo local o sistémico, como la bacteriemia no complicada o complicada (bacteriemia persistente, tromboflebitis séptica, endocarditis y otras complicaciones metastásicas). En este estudio se dan a conocer las infecciones ocasionadas por el uso de Catéter Venoso Central (CVC), así como los microorganismos presentes en los pacientes. Métodos: La investigación fue de tipo retrospectivo, descriptivo y de corte transversal, con un diseño de investigación no experimental y tuvo la finalidad de conocer, en forma directa, la realidad de la problemática. Las unidades de observación fueron (188) historias clínicas de los pacientes que ingresaron en el servicio de medicina interna en el hospital Miguel Pérez Carreño en el periodo comprendido entre enero y abril de 2017. Resultados: En 30 de los pacientes se realizó el cultivo de la punta del catéter venoso central. En el 67% no hubo crecimiento de microorganismos, mientras que el 33% crecieron microorganismos a las 24 horas. El 80% de las muestras cultivadas reportan la presencia de Cocos Gram positivos. Un 10% reportaron enterobacterias y un 10% reportan levaduras, finalmente con menor frecuencia pseudomona con un 0%. Conclusiones: Solo 78 pacientes ameritaron la colocación de un catéter venoso central, de los cuales se cultivaron 30 puntas de catéter, encontrándose que solo 10 de las puntas de catéteres dieron positivas para infección con crecimiento bacteriano a las 24 horas, siendo los cocos Gram positivos la principal bacteria aislada en los pacientes con CVC seguidos de enterobacterias(AU)

Intravascular catheterization is used for hemodynamic monitoring, hemodialysis, metabolic and nutritional support, fluid administration, chemotherapy and prolonged antibiotic therapy, blood and derivatives, among others. In this study, infections caused by the use of (CVC) central venous catheter are reported, as well as the microorganisms present in patients. Methods: The research was of a retrospective, descriptive and cross-sectional type, with a non-experimental research design and aimed to know, in a direct way, the reality of the problem. The observation units were (188) clinical records of the patients admitted to the internal medicine service at the Miguel Pérez Carreño Hospital in the period between January and April 2017. Results In 30 of the patients, the culture of the tip of the central venous catheter. In 67% there was no growth of microorganisms, while 33% grew microorganisms at 24 hours. 80% of the cultivated samples report the presence of Gram-positive cocci. 10% reported enterobacteria and 10% reported yeast, finally with less frequency pseudomonas with 0%. Conclusions: Only 78 patients required placement of a central venous catheter, of which 30 catheter tips were cultured, finding that only 10 of the catheter tips were positive for infection with bacterial growth at 24 hours, with Gram-positive cocci. the main bacteria isolated in patients with CVCfollowed by enterobacteria(AU)

A potential regulatory loop between Lin28B:miR­212 in androgen-independent prostate cancer.

Lin28 is a family of RNA binding proteins and microRNA regulators. Two members of this family have been identified: Lin28A and Lin28B, which are encoded by genes localized in different chromosomes but share a high degree of sequence identity. The role of Lin28B in androgen-independent prostate cancer (AIPC) is not well understood. Lin28B is expressed in all grades of prostatic carcinomas and prostate cancer cell lines, but not in normal prostate tissue. In this study we found that Lin28B co-localized in the nucleus and cytoplasm of the DU145 AIPC. The expression of Lin28B protein positively correlated with the expression of the c-Myc protein in the prostate cancer cell lines and silencing of Lin28B also correlated with a lower expression of the c-Myc protein, but not with the downregulation of c-Myc messenger RNA (mRNA) in the DU145 AIPC cells. We hypothesized that Lin28B regul-ates the expression of c-Myc protein by altering intermediate c-Myc suppressors. Therefore, a microRNA profile of DU145 cells was performed after Lin28B siRNA silencing. Nineteen microRNAs were upregulated and eleven microRNAs were downregulated. The most upregulated microRNAs were miR-212 and miR-2278. Prior reports have found that miR-212 is suppressed in prostate cancer. We then ran TargetScan software to find potential target mRNAs of miR-212 and miR-2278, and it predicted Lin28B mRNA as a potential target of miR-212, but not miR-2278. TargetScan also predicted that c-Myc mRNA is not a potential target of miR-212 or miR-2278. These observations suggest that Lin28B:miR-212 may work as a regulatory loop in androgen-independent prostate cancer. Furthermore, we report a predictive 2-fold symmetric model generated by the superposition of the Lin28A structure onto the I-TASSER model of Lin28B. This structural model of Lin28B suggests that it shows unique microRNA binding characteristics. Thus, if Lin28B were to bind miRNAs in a manner similar to Lin28A, conformational changes would be necessary to prevent steric clashes in the C-terminal and linker regions between the CSD and ZNF domains.

RalA signaling pathway as a therapeutic target in hepatocellular carcinoma (HCC).

Ral (Ras like) leads an important proto-oncogenic signaling pathway down-stream of Ras. In this work, RalA was found to be significantly overactivated in hepatocellular carcinoma (HCC) cells and tissues as compared to non-malignant samples. Other elements of RalA pathway such as RalBP1 and RalGDS were also expressed at higher levels in malignant samples. Inhibition of RalA by gene-specific silencing caused a robust decrease in the viability and invasiveness of HCC cells. Additionally, the use of geranyl-geranyl transferase inhibitor (GGTI, an inhibitor of Ral activation) and Aurora kinase inhibitor II resulted in a significant decrease in the proliferation of HCC cells. Furthermore, RalA activation was found to be at a higher level of activation in HCC stem cells that express CD133. Transgenic mouse model for HCC (FXR-Knockout) also revealed an elevated level of RalA-GTP in the liver tumors as compared to background animals. Finally, subcutaneous mouse model for HCC confirmed effectiveness of inhibition of aurora kinase/RalA pathway in reducing the tumorigenesis of HCC cells in vivo. In conclusion, RalA overactivation is an important determinant of malignant phenotype in differentiated and stem cells of HCC and can be considered as a target for therapeutic intervention.

[Bone mineral density disminution post Roux-Y bypass surgery]. / Disminución de masa ósea post-cirugía bariátrica con by-pass en Y de Roux.

INTRODUCTION: Bariatric surgery has important metabolic complications such as bone mass loss. GOAL: To assess bone mineral density (BMD) after Roux-en-Y gastric by-pass (RYGB) in patients under standard calcium and vitamin D supplementation. METHOD: In patients with morbid obesity submitted to RYGB, 76 women and 22 men of diverse age, all with standard nutritional instruction including vitamin D and calcium, we measured BMD with a dual X-ray densitometer. They had lumbar spine and hips measurement 2-3 years post-surgery. Twenty females were followed up with BMD until of a mean of 54 months. Using World Health Organization (WHO) criteria's, values were compared with young controls and same age and sex population, evaluating osteopenia and osteoporosis. RESULTS: Inverse correlation was observed between BMD and age; positive between BMD and body mass index as well as with preoperative weight excess. In women younger than 45 years, we observed a diminished BMD in 26.8% of them, with no cases of osteoporosis. In older females, BMD was decreased in 65.7% (p = 0.0011); corresponding to 45.7% of osteopenia and 20% osteoporosis, more frequent in lumbar spine. In the female's subgroup followed longer, BMD diminished progressively mainly in left hip. In men, there was 36% of osteopenia and 14% of osteoporosis. CONCLUSION: Patients from both genders and diverse ages after BPYR presented osteopenia and osteoporosis, despite early supplement prescription of calcium and vitamin D. We consider important to perform serial BMD measurements and also to individualize therapy with risk factors control.

Introducción: La cirugía bariátrica tiene complicaciones metabólicas importantes como la pérdida de masa ósea. Objetivo: Evaluar la densidad mineral ósea (DMO) posterior a by-pass gástrico en Y de Roux (BPYR) en pacientes con indicación de suplemento estándar de calcio y vitamina D. Método: En pacientes con BPYR por obesidad mórbida, 76 mujeres y 22 hombres de diversa edad, con instrucción nutricional, suplemento de calcio y vitamina D, se midió la DMO en columna lumbar y caderas con densitómetro radiológico de doble haz 2 a 3 años post-cirugía. Veinte mujeres fueron seguidas con DMO hasta 54 meses en promedio. Según criterios de Organización Mundial de la Salud (OMS), se comparó con población control joven y de su edad según sexo, evaluando osteopenia y osteoporosis. Resultados: Hubo correlación negativa de DMO con edad; positiva de DMO con índice de masa corporal y con exceso de peso preoperatorio. En mujeres menores de 45 años, se observó disminución de DMO en 26,8%, sin casos de osteoporosis y en 65,7% en las mayores de 45 años (p = 0,0011), correspondiendo a 45,7% de osteopenia y 20% de osteoporosis, predominantemente en columna lumbar. El subgrupo de mujeres con mayor seguimiento, presentó disminución progresiva de DMO, especialmente en cadera izquierda. En hombres se observó 36% de osteopenia y 14% de osteoporosis. Conclusión: Pacientes de ambos sexos y diversa edad, despues de un BPYR, presentaron osteopenia y osteoporosis, a pesar de suplemento precoz de calcio y vitamina D. Consideramos importante medir DMO seriada, individualizando terapias y controlando factores de riesgo.

Type 2 diabetes mellitus in patients with mild obesity: preliminary results of surgical treatment.

In the last years, type 2 diabetes mellitus (T2DM) and obesity have become a serious public health problem, behaving as epidemic diseases. There is great interest in exploring different options for the treatment of T2DM in nonmorbidly obese patients. The purpose of this study is to report parameters of glycemic control in patients with T2DM and mild obesity who underwent laparoscopic Roux-en-Y gastric bypass (RYGBP). This prospective clinical trial includes patients with T2DM with a body mass index (BMI) between 30 and 35 kg/m(2) who underwent laparoscopic RYGBP from July 2008 through October 2010. Thirty-one patients were included in the study, 15 men and 16 women, with an average age of 48.7 ± 8.6 years. The average time since onset of T2DM was 5.8 years. The average postoperative follow-up was 30.4 months. The average preoperative blood glucose and glycosylated hemoglobin were 152 ± 70 mg/dl and 7.7 ± 2.1 %, respectively. All of them were using oral hypoglycemic agents, and four patients were insulin dependent. Only one patient had a postoperative complication (hemoperitoneum). At 36 months follow-up, the average BMI decreased to 24.7 kg/m(2), all patients (31) showed improvement in their glycemic control, and 29 of them (93.6 %) met the criteria for remission of T2DM in the last control. Laparoscopic RYGBP is a safe and effective procedure that improves glycemic control in patients with T2DM and mild obesity at midterm follow-up.

A second-generation 2-Methoxyestradiol prodrug is effective against Barrett's adenocarcinoma in a mouse xenograft model.

2-Methoxyestradiol (2-ME2) is an endogenous metabolite of estradiol. In preclinical models, 2-ME2 is effective against different types of tumors. Unfortunately, only low systemic concentrations of 2-ME2 can be achieved following oral administration, even after very high doses are administered to patients. In an effort to solve this problem, we have now synthesized and tested a new prodrug of 2-ME2 that is water-soluble due to a bioreversible hydrophilic group added at the 3-position and that more effectively resists metabolic inactivation due to an ester moiety added to mask the 17-position alcohol. We are reporting here for the first time that this double prodrug of 2-ME2 is effective as an antiproliferative and anticancer agent for both in vitro and in vivo studies against Barrett esophageal adenocarcinoma (BEAC) and provided greater potency than 2-ME2 in inhibiting the growth of BEAC xenografts. Finally, studies indicate that, like 2-ME2, the 2-ME2-PD1 exhibits anticancer effect through possible disruption of microtubule network.

Pro-oncogenic cell signaling machinery as a target for oncolytic viruses.

Viruses function in close harmony with the signaling machinery of their host. Upon exposure to the cell, a battery of viral products become engaged in boosting friendly signaling elements of the host or suppressing harmful ones. The efficiency of viral replication is indeed the biological outcome of this interaction between cellular and host signaling molecules. Oncolytic viruses, natural or man-made, follow the same set of rules of engagement. Pro-oncogenic cell signaling machinery, therefore, is undoubtedly the most important area influencing the development of the next generation of effective, specific and rationally designed oncolytic viruses. Ras signaling, with its central role in what is known today as molecular oncology, is an attractive topic for studying the behavior of viruses versus cancer cells and to develop strategies to target cancer cells on the basis of such platform. This work reviews the development of oncolytic herpes viruses capable of targeting Ras signaling pathway along with a few other examples of viruses which are developed to contain specificity for certain pro-oncogenic characteristics of their host cells.

Inhibition of mesothelin as a novel strategy for targeting cancer cells.

Mesothelin, a differentiation antigen present in a series of malignancies such as mesothelioma, ovarian, lung and pancreatic cancer, has been studied as a marker for diagnosis and a target for immunotherapy. We, however, were interested in evaluating the effects of direct targeting of Mesothelin on the viability of cancer cells as the first step towards developing a novel therapeutic strategy. We report here that gene specific silencing for Mesothelin by distinct methods (siRNA and microRNA) decreased viability of cancer cells from different origins such as mesothelioma (H2373), ovarian cancer (Skov3 and Ovcar-5) and pancreatic cancer (Miapaca2 and Panc-1). Additionally, the invasiveness of cancer cells was also significantly decreased upon such treatment. We then investigated pro-oncogenic signaling characteristics of cells upon mesothelin-silencing which revealed a significant decrease in phospho-ERK1 and PI3K/AKT activity. The molecular mechanism of reduced invasiveness was connected to the reduced expression of ß-Catenin, an important marker of EMT (epithelial-mesenchymal transition). Ero1, a protein involved in clearing unfolded proteins and a member of the ER-Stress (endoplasmic reticulum-stress) pathway was also markedly reduced. Furthermore, Mesothelin silencing caused a significant increase in fraction of cancer cells in S-phase. In next step, treatment of ovarian cancer cells (OVca429) with a lentivirus expressing anti-mesothelin microRNA resulted in significant loss of viability, invasiveness, and morphological alterations. Therefore, we propose the inhibition of Mesothelin as a potential novel strategy for targeting human malignancies.

Inhibition of RalA signaling pathway in treatment of non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer and relatively resistant to chemotherapy. The most prevalent molecular abnormality in NSCLC is the overactivation of K-Ras proto-oncogene; therefore, elucidating down-stream Ras signaling in NSCLC is significantly important in developing novel therapies against this malignancy. Our work indicates that RalA, an important effector of Ras, is activated in NSCLC cell lines. While RalA was also overactivated in fetal human broncho-epithelial cells, RalBP1 (Ral binding protein-1), an important down-stream effector of RalA, was expressed at higher levels in cancer cell lines. Aurora kinase-A (AKA), an upstream activator of RalA, was also found to be active only in malignant cells. The outcome of inhibition of RalA (by gene specific silencing using a lentivirus) on the malignant phenotype of A549 cells was also studied. While proliferation and invasiveness of A549 cells were reduced upon silencing RalA, apoptosis and necrosis were elevated in such conditions. Additionally, the in vivo tumorigenesis of A549 cells was reduced upon partial inhibition of RalA and AKA using pharmacological inhibitors. Finally, we were interested in evaluating the level of active RalA in the fraction of NSCLC cells expressing cancer stem cell markers. For this purpose cells with increased expression of CD44 were separated from A549 cells and compared with cells with low level of expression of this marker and an unsorted population. A significant enhancement of RalA activation in high CD44+ cells was found as potential evidence for involvement of RalA signaling in initiation of the neoplastic procedure and an important contributor for tumor maintenance in NSCLC. Further studies can reveal therapeutic, preventive and diagnostic value of RalA pathway in this deadly disease.

Calidad de la alimentación de mujeres con obesidad severa y mórbida sometidas a bypass gastrico y gastrectomia vertical en manga

El objetivo de este estudio fue comparar la ingesta de energía y nutrientes y la calidad de la alimentación, en pacientes sometidos a bypass gástrico en Y de Roux y (BPGYR) y gastrectomía vertical en manga (GVM). En 36 mujeres con obesidad severa y mórbida se estudió la alimentación previa y a los 6 meses posteriores a la cirugía, mediante encuesta de registro de tres días, se analizó el grado de adecuación e índice de calidad nutricional (ICN). Se controló estrictamente el consumo de suplementos de vitaminas y minerales. El consumo de energía y nutrientes fue significativamente menor al sexto mes post cirugía comparado con el preoperatorio, sin diferencias significativas entre grupos, excepto calcio y vitamina C. El ICN fue similar entre grupos. La ingesta dietética de calcio, hierro, zinc, cobre, ácido fólico, vitamina C y E fue menor al 100% de adecuación al 6º mes. Sin embargo, al considerar en conjunto el aporte de la dieta como de los suplementos, la adecuación de prácticamente todos los nutrientes estudiados sobrepasa el 100% en ambos grupos, logrando una mayor adecuación el grupo sometido a BPGYR. Las excepciones las constituyen el calcio, el cual no alcanza a cubrir el 100% en ningún grupo y el ácido fólico en el grupo sometido a GVM. En conclusión, estos pacientes presentan reducciones importantes de la ingesta dietética de energía y micronutrientes, sin mayores diferencias dependientes del tipo de cirugía. Las características de los suplementos son críticos para lograr la cobertura de las necesidades.

The objective of this study was to evaluate the changes of dietary intake and quality of the diet in patients undergoing gastric bypass and sleeve surgery. In 36 women with severe and morbid obesity it was assessed their nutrient intakes and dietary quality before and 6 months after bariatric surgery through three-day food records. Vitamin and mineral intakes from supplements were strictly controlled. Energy and nutrient intakes were significantly decreased 6 months after surgery bypass compared to the pre-surgery period, with the exceptions of calcium and vitamin C. No differences were observed between groups. The Dietary quality index was also similar in both groups. Dietary intakes of calcium, iron, zinc, copper, folic acid, vitamin C, and vitamin E were below 100% of adequacy from at the 6th month after the surgery. Nevertheless, by considering both diet and supplements supply, nutrient adequacy of all but calcium and folic acid was above 100% in both groups. Gastric bypass patients presented greater values. In conclusion, these patients present an important reduction of their energy and nutrient intakes, with no major impact of the type of surgery. Supplement characteristics are crucial to cover nutritional needs.

Crystal structure of the actin-binding domain of alpha-actinin 1: evaluating two competing actin-binding models.

Alpha-actinin belongs to the spectrin family of actin crosslinking and bundling proteins that function as key regulators of cell motility, morphology and adhesion. The actin-binding domain (ABD) of these proteins consists of two consecutive calponin homology (CH) domains. Electron microscopy studies on ABDs appear to support two competing actin-binding models, extended and compact, whereas the crystal structures typically display a compact conformation. We have determined the 1.7A resolution structure of the ABD of alpha-actinin 1, a ubiquitously expressed isoform. The structure displays the classical compact conformation. We evaluated the two binding models by surface conservation analysis. The results show a conserved surface that spans both domains and corresponds to two previously identified actin-binding sites (ABS2 and ABS3). A third, and probably less important site, ABS1, is mostly buried in the compact conformation. However, a thorough examination of existing structures suggests a weak and semi-polar binding interface between the two CHs, leaving open the possibility of domain reorientation or opening. Our results are consistent with a two-step binding mechanism in which the ABD interacts first in the compact form observed in the structures, and then transitions toward a higher affinity state, possibly through minor rearrangement of the domains.