Improvement of Docetaxel Efficacy through Simultaneous Blockade of Transcription Factors NF-κB and STAT-3 Using Pentoxifylline and Stattic in Prostate Cancer Cells.

Prostate cancer (PCa) is a common and deadly disease in men. It is often diagnosed at advanced stages, at which point patients are treated mainly with docetaxel (DTX), which is effective but limited by resistance and side effects. Overactivation of the transcription factors NF-κB and STAT-3 plays a critical role in the development, progression, and chemoresistance of PCa. In this regard, the blockade of NF-κB with pentoxifylline (PTX) or STAT-3 with Stattic (STT) is known to increase the sensitivity of tumor cells to chemotherapy in both in vitro and in vivo models. We investigated whether simultaneous blockade with PTX and STT increases the efficacy of the DTX treatment in inducing apoptosis in metastatic castration-resistant PCa DU-145 cells. Our results showed that the combination of PTX + STT led to higher levels of apoptosis, regardless of whether or not DTX was present in the treatment. Determining caspases and ΔΨm indicates that the intrinsic caspase pathway of apoptosis is principally favored. In addition, this combination inhibited proliferation and colony formation and arrested the cell cycle in the G1 phase. These results indicate that the combination of the PTX + STAT-3 inhibitor could potentiate DTX effectively, opening the possibility of effective treatments in PCa.

Evaluating the In Vitro Activity and Safety of Modified LfcinB Peptides as Potential Colon Anticancer Agents: Cell Line Studies and Insect-Based Toxicity Assessments.

Anticancer peptides are increasingly being considered as alternative treatments for cancer due to their potency, selectivity, and low toxicity. Previously, the peptide LfcinB (21-25)Pal showed in vitro anticancer effects against the Caco-2 colon cancer cell line (half-maximal inhibitory concentration (IC50): 86 µM). In this study, we developed modifications to the peptide sequence to increase its anticancer activity. Sequence modifications were made such as the inclusion of amino hexanoic acid (Ahx), N-terminal biotinylation, acetylation, and substitutions of Orn for Arg and/or d-Arg by l-Arg. The molecules were synthesized using manual solid-phase peptide synthesis (SPPS), and their synthetic feasibility (SAScore) ranged from 6.2 to 7.6. The chromatographic purities of the synthesized peptides were greater than 89%. We found that Ahx-RWQWRWQWR and RWQWRWQW-Orn showed activity against both Caco-2 and HT-29 cell lines and decreased IC50 values by approx. 50% in Caco-2 cells (IC50: 40 µM) when compared to the parent peptide RWQWRWQWR. Moreover, the modified peptides demonstrated lower hemolytic effects, with values <10% at 200 µg/mL. Toxicity was assessed using the Galleria mellonella model and the half-maximal lethal dose (LD50) for the best peptides was >100 mg/kg, indicating that their toxicity is classified as moderately toxic or lower. In contrast, cisplatin showed an LD50 of 13 mg/Kg. The designed anticancer peptides presented good in vitro activity and low toxicity, making them promising molecules for future drug development studies.

Pentoxifylline Inhibits TNF-α/TGF-ß1-Induced Epithelial-Mesenchymal Transition via Suppressing the NF-κB Pathway and SERPINE1 Expression in CaSki Cells.

Cervical cancer (CC) is one of the most common and deadly types of female cancer worldwide. Late diagnosis in CC increases the risk of tumor cells spreading to distant organs (metastasis). The epithelial-mesenchymal transition (EMT) is a fundamental process of cancer metastasis. Inflammation can lead to tumor progression, EMT induction, and metastasis. The inflammatory microenvironment is a potent inducer of EMT; inflammatory cytokines such as Tumor Necrosis Factor-alpha (TNF-α) and Transforming growth factor-beta (TGF-ß1) activate transcriptional factors such as STAT3, Snail, Smad, and the Nuclear Factor kappa light-chain-enhancer of activated beta cells (NF-κΒ), which drive EMT. Anti-inflammatory compounds may be an option in the disruption of EMT. PenToXifylline (PTX) possesses potent anti-inflammatory effects by inhibiting NF-κB activity. In addition, PTX exerts an anti-fibrotic effect by decreasing Smad2/3/4. We hypothesize that PTX could exert anti-EMT effects. CaSki human cervical tumor cells were exposed to TNF-α 10 ng/mL and TGF-ß1 alone or in combination for 5 days. Our results revealed that TNF-α and TGF-ß1 induced N-cadherin and Vimentin, confirming the induction of EMT. Furthermore, the combination of cytokines synergized the expression of mesenchymal proteins, enhanced IκBα and p65 phosphorylation, and upregulated Serpin family E member 1 (SERPINE1) mRNA. PTX pretreatment prior to the addition of TNF-α and TGF-ß1 significantly reduced N-cadherin and Vimentin levels. To our knowledge, this is the first time that this effect of PTX has been reported. Additionally, PTX reduced the phosphorylation of IκB-α and p65 and significantly decreased SERPINE1 expression, cell proliferation, migration, and invasion. In conclusion, PTX may counteract EMT in cervical cancer cells by decreasing the NF-κB and SERPINE1.

Non-natural amino acids into LfcinB-derived peptides: effect in their (i) proteolytic degradation and (ii) cytotoxic activity against cancer cells.

The dimeric peptide 26[F]: (RRWQWRFKKLG)2-K-Ahx has exhibited a potent cytotoxic effect against breast cancer cell lines, with position 26 (F) being the most relevant for anti-cancer activity. In this investigation, six analogues of the 26[F] peptide were synthesized in which the 26th position was replaced by non-natural hydrophobic amino acids, finding that some modifications increased the resistance to proteolytic degradation exerted by trypsin or pepsin. Additionally, these modifications increased the cytotoxic effect against breast cancer cells and generated cell death mediated by apoptosis pathways, activating caspases 8 and 9, and did not compromise the integrity of the cytoplasmic membrane. Finally, it was found that the modified peptides have a broad spectrum of action, since they also have a cytotoxic effect against the HeLa human cervical cancer cell line. Peptide 26[F] was inoculated in mice by ip administration and the lethal dose 50 (LD50) was between 70 and 140 mg kg-1. While for the 26[1-Nal]: (RRWQWR-1-Nal-KKLG)2-K-Ahx peptide, a dose-response test was performed, and the survival rate was 100%. These results suggested that these peptides are safe in this animal model and could be considered as promissory to develop a treatment against breast cancer.

Defining the regulatory mechanisms of sigma factor RpoS degradation in Azotobacter vinelandii and Pseudomonas aeruginosa.

In several Gram-negative bacteria, the general stress response is mediated by the alternative sigma factor RpoS, a subunit of RNA polymerase that confers promoter specificity. In Escherichia coli, regulation of protein levels of RpoS involves the adaptor protein RssB, which binds RpoS for presenting it to the ClpXP protease for its degradation. However, in species from the Pseudomonadaceae family, RpoS is also degraded by ClpXP, but an adaptor has not been experimentally demonstrated. Here, we investigated the role of an E. coli RssB-like protein in two representative Pseudomonadaceae species such as Azotobacter vinelandii and Pseudomonas aeruginosa. In these bacteria, inactivation of the rssB gene increased the levels and stability of RpoS during exponential growth. Downstream of rssB lies a gene that encodes a protein annotated as an anti-sigma factor antagonist (rssC). However, inactivation of rssC in both A. vinelandii and P. aeruginosa also increased the RpoS protein levels, suggesting that RssB and RssC work together to control RpoS degradation. Furthermore, we identified an in vivo interaction between RssB and RpoS only in the presence of RssC using a bacterial three-hybrid system. We propose that both RssB and RssC are necessary for the ClpXP-dependent RpoS degradation during exponential growth in two species of the Pseudomonadaceae family.

Manejo de tejidos blandos en trauma de miembros inferiores: a propósito de un caso / Soft tissue management in lower limb trauma: about a case

Los miembros inferiores están sujetos frecuentemente a traumas que ocasionan daño de estructuras vitales y que pueden dejar secuelas funcionales y estéticas en las personas. Las lesiones de tejidos blandos son las que asientan en la piel, tejido celular subcutáneo, aponeurosis, músculos, vasos y nervios. Del manejo oportuno y adecuado de las lesiones que se presenten posteriores a un trauma de tejidos blandos dependerá el resultado, el tiempo de recuperación, costos de hospitalización y sobre todo la preservación de las funciones de locomoción y sostén del miembro afectado

The lower limbs are frequently exposed to traumas that cause vital structures damage and can leave functional and aesthetic sequelae in patients. Soft tissue lesions are those that affect the skin, subcutaneous cellular tissue, fascia, muscles, vessels, and nerves. The result, recovery time, hospitalization costs and, above all, the preservation of the locomotion and support functions of the affected limb will depend on the timely and adequate management of injuries that occur after a soft tissue trauma.

Ataque de nervios: The impact of sociodemographic, health history, and psychological dimensions on Puerto Rican adults.

Introduction: Ataque de nervios (ADN) is a cultural syndrome prevalent in Puerto Ricans characterized as an episode of intense emotional upset due to overwhelming stress. Methods: The Ataque de Nervios Questionnaire, developed at the Center for the Study and Treatment for Fear and Anxiety (CETMA), served as the diagnostic tool for this retrospective secondary data analysis. We evaluated three models regarding ADN's function as a marker of (1) sociodemographic vulnerability, (2) health history risk, and (3) psychological vulnerability. This last model was subdivided to assess the scores of screening tests regarding anxiety (Anxiety Sensitivity Inventory, Beck Anxiety Inventory, and State-Trait Anxiety Inventory), affect (Beck Depression Inventory, Emotional Dysregulation Scale, Positive and Negative Affective Schedule), personality (NEO Five-Factor Inventory), and trauma (considering the responses to the Childhood Trauma Questionnaire and the Life Event Checklist). Results: Our study sample had a total of 121 Puerto Rican adult patients from CETMA out of which 75% had ADN. We differentiated subjects according to their ADN status with t-tests and Mann-Whitney U tests and evaluated our models using logistic regressions. People with ADN showed more anxiety, depressive symptoms, emotional dysregulation, and negative affect than those without ADN. They also revealed lower positive affect and agreeableness. Highly extraverted but minimally agreeable personalities related to ADN. Living with a partner and being employed were risk factors for ADN. Having higher educational levels showed the strongest effect size: it greatly reduced the odds of an ataque. Discussion: These characteristics suggest a distinct profile of ADN seen in employed, educated, adult Puerto Ricans living on the Island experiencing anxiety. Our study provides clinical tools to comprehend our patients' ADN experience, enriching our practice as culturally competent health providers.

Esquizencefalia de diagnóstico prenatal: reporte de caso / Schizencephaly of prenatal diagnosis: case report

La esquizencefalia es una malformación cerebral congénita del grupo de trastornos de migración neuronal, tiene una prevalencia de 1,54/100 000 nacidos vivos, por lo cual, se considera extremadamente rara. El objetivo de este artículo es presentar un caso de esquizencefalia fetal de labio abierto, el subtipo de peor pronóstico, cuya sospecha diagnóstica se realiza con ecografía prenatal y se confirma mediante la resonancia magnética fetal. Actualmente, en Colombia no se cuenta con este tipo de reporte de casos.

Schizencephaly is a congenital brain malformation, which is part of the group of neuronal migration disorders, which has a prevalence of 1,54/100 000 in live births, which is why it is considered extremely rare in Colombia. The objective of this article is to present a case of open-lip fetal schizencephaly, the subtype with the worst prognosis, whose suspected diagnosis is made with prenatal ultrasound and confirmed by fetal magnetic resonance imaging. Currently, this type of report is not available in Colombia.

Principios bioéticos y actitudes en la atención de pacientes con VIH, del Hopital Clínico Viedma, 2021 / Bioethical principles and attitudes in the care of patients with HIV, Hospital Clínico Viedma, 2021

La infección por el Virus de la inmunodeficiencia humana, el estigma y la discriminación, así como su interrelación con los derechos humanos, se han transformado en los ejes centrales de las campañas contra el SIDA y a favor de los derechos de las personas viviendo con el VIH/SIDA, constituyéndose en uno de los problemas más frecuentes en el área hospitalaria. El presente estudio se realizó para identificar los principios bioéticos y actitudes del personal de enfermería, elementos de valoración y cuidados que implementan el personal para la prevención de las mismas; con el enfoque cualitativo - cuantitativo de tipo descriptivo y transversal, en el servicio de Infectología del HCV, gestión II/2021. Los resultados más significativos del personal de enfermería son: discriminación con el 20%; rechazo, 20%; actitudes negativas, 20% un 27% percibe una mala atención y 13% trato inadecuado, por tanto 100% de la población ha recibido algún tipo de maltrato del personal de enfermería. Pese a que estos conocen los principios bioéticos de autonomía, beneficencia, no maleficencia y equidad con los pacientes, solo en la parte teórica, ya que en la práctica no las aplican. (AU)

Evidence for Light and Tissue Specific Regulation of Genes Involved in Fructan Metabolism in Agave tequilana.

Plant Glycoside Hydrolase Family 32 (PGHF32) contains the fructosyltransferases and fructan exohydrolase enzymes responsible for fructan metabolism, in addition to closely related vacuolar and cell wall acid invertases. Agave species produce complex and dynamic fructan molecules (agavins) requiring 4 different fructosyltransferase activities (1-SST, 1-FFT, 6G-FFT and 6-SFT) for their synthesis. Combined analysis of RNAseq and genome data for A. tequilana led to the characterization of the genes encoding 3 fructosyltransferases for this species and support the hypothesis that no separate 6-SFT type enzyme exists in A. tequilana, suggesting that at least one of the fructosyltransferases identified may have multiple enzymatic activities. Structures for PGHF32 genes varied for A. tequilana and between other plant species but were conserved for different enzyme types within a species. The observed patterns are consistent with the formation of distinct gene structures by intron loss. Promoter analysis of the PGHF32 genes identified abundant putative regulatory motifs for light regulation and tissue-specific expression, and these regulatory mechanisms were confirmed experimentally for leaf tissue. Motifs for phytohormone response, carbohydrate metabolism and dehydration responses were also uncovered. Based on the regulatory motifs, full-length cDNAs for MYB, GATA, DOF and GBF transcription factors were identified and their phylogenetic distribution determined by comparison with other plant species. In silico expression analysis for the selected transcription factors revealed both tissue-specific and developmental patterns of expression, allowing candidates to be identified for detailed analysis of the regulation of fructan metabolism in A. tequilana at the molecular level.

Estimating COVID-19 cases in Puerto Rico using an automated surveillance system.

Due to concerns regarding limited testing and accuracy of estimation of COVID-19 cases, we created an automated surveillance system called "Puerto Rico Epidemiological Evaluation and Prevention of COVID-19 and Influenza" (PREPCOVI) to evaluate COVID-19 incidence and time trends across Puerto Rico. Automated text message invitations were sent to random phone numbers with Puerto Rican area codes. In addition to reported COVID-19 test results, we used a published model to classify cases from specific symptoms (loss of smell and taste, severe persistent cough, severe fatigue, and skipped meals). Between 18 November 2020, and 24 June 2021, we sent 1,427,241 messages, 26.8% were reached, and 6,975 participants answered questions about the last 30 days. Participants were aged 21-93 years and represented 97.4% of the municipalities. PREPCOVI total COVID-19 cases were higher among women and people aged between 21 and 40 years and in the Arecibo and Bayamón regions. COVID-19 was confirmed, and probable cases decreased over the study period. Confirmed COVID-19 cases ranged from 1.6 to 0.2% monthly, although testing rates only ranged from 30 to 42%. Test positivity decreased from 13.2% in November to 6.4% in March, increased in April (11.1%), and decreased in June (1.5%). PREPCOVI total cases (6.5%) were higher than cases reported by the Puerto Rico Department of Health (5.3%) for similar time periods, but time trends were similar. Automated surveillance systems and symptom-based models are useful in estimating COVID-19 cases and time trends, especially when testing is limited.

The burned patient in times of COVID-19: proposal derived from lessons learned.

COVID-19 is a public health problem, so any burn patient who is managed as an outpatient or requires hospital management is a potential carrier of SARS-CoV-2. Burn patients are susceptible to COVID-19 due to the burn and its immunosuppressive effect, the procedures they undergo and other factors related to the burn, which makes them at high risk of contracting the disease and transmitting it, especially to the healthcare team involved in its management. Therefore, it is important to organize strategies in the services that care for burn patients during the COVID-19 pandemic. The objective of this paper is to present a proposal for response, organizational management and strategic planning in a burns service in times of COVID-19, based on the lessons and experience acquired.

La COVID-19 es un problema de salud pública, por lo que cualquier paciente quemado que se maneje como externo o que requiera manejo hospitalario es un potencial portador del SARS-CoV-2. El paciente quemado es susceptible a la COVID-19 debido a la quemadura y a su efecto inmunodepresor, a los procedimientos a los que es sometido y a otros factores inherentes a la quemadura, lo que le hace un paciente con alto riesgo de contraer la enfermedad y trasmitirla, especialmente al equipo de salud que está involucrado en su manejo. Por lo anterior, es importante organizar estrategias en los servicios que atienden pacientes con quemaduras durante la pandemia de COVID-19. El objetivo de este trabajo es presentar una propuesta para la respuesta, el manejo organizativo y la planeación estratégica en un servicio de quemados en tiempos de COVID-19, basándonos en las lecciones aprendidas y la experiencia adquirida.

[Clinical cases of Guillain-Barré and Miller-Fisher syndromes linked to COVID-19]. / Casos clínicos de los síndromes de Guillain-Barré y Miller-Fisher relacionados con la COVID-19.

coronavirus disease 2019 (COVID-19), caused by the new coronavirus SARS-CoV-2, has been associated with the development of neurological diseases such as Guillain-Barré syndrome (GBS) and its variants. In the present work, two cases of demyelinating syndromes associated with COVID-19 are reported. Clinical cases: 53-year-old male with GBS and and 29-year-old female with Miller-Fisher syndrome (MFS) variant, respectively. Both patients presented the classic neurological signs and symptoms of demyelinating polyneuropathy that characterizes the syndromes. From the paraclinical biochemical tests, the increase of proteins in cerebrospinal fluid was distinctive. The positivity of the RT-qPCR for SARS-CoV-2 suggested the association of GBS and MFS with COVID-19. Both patients were treated with intravenous immunoglobulin showing improvement. Electromyography performed weeks ahead still showed chronic demyelinating involvement. Conclusion: The cases of GBS and MFS, along with other similar cases reported around the world, provide further evidence for SARS-CoV-2 as a new possible etiology of these rare neurological diseases.

Introducción: la enfermedad por coronavirus del 2019 (COVID-19), causada por el nuevo coronavirus SARS-CoV-2, se ha asociado con el desarrollo de enfermedades neurológicas como el síndrome de Guillain-Barré (SGB) y sus variantes. En el presente trabajo se reportan dos casos de síndromes desmielizantes asociados con la COVID-19. Casos clínicos: hombre de 53 años con SGB y mujer de 29 años con la variante del síndrome de Miller-Fisher (SMF), respectivamente. Ambos presentaron los signos y síntomas neurológicos clásicos de polineuropatía desmielinizante que caracterizan a estos síndromes. De las pruebas bioquímicas paraclínicas, el aumento de proteínas en líquido cefalorraquídeo fue distintiva. La positividad de la RT-qPCR para el SARS-CoV-2 indicó la asociación de los SGB y SMF con la COVID-19. Ambos pacientes se trataron con inmunoglobulina intravenosa y mostraron mejoría. La electromiografía realizada en semanas posteriores aún mostraba afectación desmielinizante crónica. Conclusión: los casos de los SGB y SMF, junto con otros casos similares reportados en todo el mundo, proporcionan más evidencia para el SARS-CoV-2 como nueva posible etiología de estas raras enfermedades neurológicas.

Casos clínicos de los síndromes de Guillain-Barré y Miller-Fisher relacionados con la COVID-19 / Clinical cases of Guillain-Barré and Miller-Fisher syndromes linked to COVID-19

Introducción: la enfermedad por coronavirus del 2019 (COVID-19), causada por el nuevo coronavirus SARSCoV-2, se ha asociado con el desarrollo de enfermedades neurológicas como el síndrome de Guillain-Barré (SGB) y sus variantes. En el presente trabajo se reportan dos casos de síndromes desmielizantes asociados con la COVID-19. Casos clínicos: hombre de 53 años con SGB y mujer de 29 años con la variante del síndrome de Miller-Fisher (SMF), respectivamente. Ambos presentaron los signos y síntomas neurológicos clásicos de polineuropatía desmielinizante que caracterizan a estos síndromes. De las pruebas bioquímicas paraclínicas, el aumento de proteínas en líquido cefalorraquídeo fue distintiva. La positividad de la RT-qPCR para el SARS-CoV-2 indicó la asociación de los SGB y SMF con la COVID-19. Ambos pacientes se trataron con inmunoglobulina intravenosa y mostraron mejoría. La electromiografía realizada en semanas posteriores aún mostrabaafectación desmielinizante crónica. Conclusión: los casos de los SGB y SMF, junto con otros casos similares reportados en todo el mundo, proporcionan más evidencia para el SARS-CoV-2 como nueva posible etiología de estas raras enfermedades neurológicas.

Background: coronavirus disease 2019 (COVID-19), caused by the new coronavirus SARS CoV-2, has been associated with the development of neurological diseases such as Guillain-Barré syndrome (GBS) and its variants. In the present work, two cases of demyelinating syndromes associated with COVID-19 are reported. Clinical cases: 53-year-old male with GBS and and 29-yearold female with Miller-Fisher syndrome (MFS) variant, respectively. Both patients presented the classic neurological signs and symptoms of demyelinating polyneuropathy that characterizes the syndromes. From the paraclinical biochemical tests, the increase of proteins in cerebrospinal fluid was distinctive. The positivity of the RT-qPCR for SARSCoV-2 suggested the association of GBS and MFS with COVID-19. Both patients were treated with intravenous immunoglobulin showing improvement. Electromyography performed weeks ahead still showed chronic demyelinating involvement. Conclusion: The cases of GBS and MFS, along with other similar cases reported around the world, provide further evidence for SARS-CoV-2 as a new possible etiology of these rare neurological diseases.

Coaching tailored by stages: A valuable educational strategy to achieve independence in research.

This study presents an individualized coaching approach tailored to the stages of proximity of promising scientists interested in becoming independently funded researchers in the context of a minority-serving institution. This strategy defined the participant's stage of proximity by their number of first-author publications in peer-reviewed journals and their track record in submitting research grants. We argue that coaching tailored by stages is an asset to maintain the enthusiasm, persistence, and positive attitude of promising scientists as they try to reach independent investigator status. Furthermore, this valuable educational approach supports the development of management and leadership skills in defined scientific domains.

Public Health Academic Alliance for COVID-19 Response: The Role of a National Medical Task Force in Puerto Rico.

Alliances between the government and academic communities can be a key component of the public health response to an emergency such as the coronavirus disease 2019 (COVID-19) pandemic. The Governor of Puerto Rico designated the Puerto Rico Medical Task Force (MTF) COVID-19 to provide direct guidance and evaluation of the government response to the epidemic in Puerto Rico. Several work groups were formed within the MTF to create protocols and provide evidence-based recommendations on different public health aspects. The collaboration between the academia and the government enhanced the Puerto Rican public health response and contributed to the reduction seen in the contagion curve. Healthcare services and hospitals have not reached their maximum patient care capacity and the death toll has been controlled. Incorporating a national MTF with members of the academia into the government structure was beneficial during the COVID-19 response in Puerto Rico. A similar strategy could serve as a model for other states or territories and countries in similar scenarios.

Genotoxic Effects of Aluminum Chloride and Their Relationship with N-Nitroso-N-Methylurea (NMU)-Induced Breast Cancer in Sprague Dawley Rats.

Recently, soluble forms of aluminum for human use or consumption have been determined to be potentially toxic due to their association with hepatic, neurological, hematological, neoplastic, and bone conditions. This study aims to assess the genotoxic effect of aluminum chloride on genomic instability associated with the onset of N-nitroso-N-methylurea (NMU)-induced breast cancer in Sprague Dawley rats. The dietary behavior of the rats was assessed, and the concentration of aluminum in the mammary glands was determined using atomic absorption spectroscopy. Genomic instability was determined in the histological sections of mammary glands stained with hematoxylin and eosin. Moreover, micronucleus in peripheral blood and comet assays were performed. The results of dietary behavior evaluation indicated no significant differences between the experimental treatments. However, aluminum concentration in breast tissues was high in the +2000Al/-NMU treatment. This experimental treatment caused moderate intraductal cell proliferation, lymph node hyperplasia, and serous gland adenoma. Furthermore, micronucleus and comet test results revealed that +2000Al/-NMU led to a genotoxic effect after a 10-day exposure and the damage was more evident after a 15-day exposure. Therefore, in conclusion, genomic instability is present and the experimental conditions assessed are not associated with breast cancer.

Electromyography Biofeedback Exergames to Enhance Grip Strength and Motivation.

BACKGROUND: Hand strength weakness affects the performance of most activities of daily living. This study aims to design, develop, and test an electromyography (EMG) biofeedback training system based on serious games to promote motivation and synchronization and proper work intensity in grip exercises for improving hand strength. MATERIALS AND METHODS: An EMG surface sensor, soft balls with different stiffness and three exergames, conforms the system to drive videogame clues in response to EMG-inferred grip strength, while overseeing motivation. An experiment was designed to study the effect of performing handgrip (HG) exercises with the proposed system versus traditional exercises. Participants, organized into two groups, followed a training program for each hand. One group followed a HG exergame training (ET) with the dominant hand and traditional HG training with the nondominant hand and inverse sequence by the second group. Initial and final grip forces were measured using a digital dynamometer. Questionnaires evaluated motivation and user experience, and exercise performance was evaluated in terms of work and rest time percentage and maximal voluntary contraction percentage over contraction periods. Data were analyzed for statistically significant differences and increase of means. RESULTS: Participants showed significantly better exercise performance and higher grip forces, with sustained intrinsic motivation and user experience, with the ET. CONCLUSION: Improvement in force level arises evidently from the synchronized work-rest time pattern and appropriated intensity of the muscle activity. This leads to support that EMG biofeedback exergames improve motor neurons firing and resting.

Distribución de la tensión compresiva en segundas premolares superiores en coronas individuales mediante el análisis de elementos finitos / Distribution of compressive tension in second higher premolars in individual crowns through the finite element analysis

Objetivo: Evaluar la tensión compresiva en segundas premolares superiores rehabilitadas con coronas de disilicato de litio (D.L) y de Silicato de litio reforzado con zirconio (S.L) mediante el método de elementos finitos. Metodología: Se construyeron dos modelos virtuales usando el programa Solidworks 2014 para la construcción de modelos. En el primer modelo se representó la dentina remanente, cofia de disilicato de litio, cemento relyx U 200 y porcelana cerámica feldespática IPS e.Max (Ivoclar Vivadent) (MEF 1). En el segundo modelo se representó la dentina remanente, cofia de vita suprinity, cemento relyx U 200 y porcelana (MEF 2). Ambos modelos fueron sometidos a una carga de 200 N. Resultados: El valor de máxima tensión en la corona de disilicato de litio (MEF 1) fue de 166.98 Mpa, mientras que en la corona de Silicato de litio (MEF 2) fue de 177.6 Mpa. El valor de máxima tensión compresiva en dentina en el (MEF 1) fue 0.27 Mpa y en el (MEF 2) la máxima tensión en la dentina fue 0.26 Mpa. El valor de máxima tensión compresiva en cervical del (MEF 1) fue de 3.93 Mpa y en el (MEF 2) en cervical fue de 3.90 Mpa. Conclusiones: La corona de silicato de litio mostró la mayor tensión compresiva en el área oclusomesial. En dentina y en el área cervical la tensión compresiva tuvieron resultados similares. (AU)

Objective:To evaluate compressive stress between the disilicate (D.L) and Zirconium reinforced lithium silicate (S.L) crowns using finite element analysis.Material and Methods:Two virtual models were constructed using the Solidworks 2014 software for building models. In the first model was designed the remaining dentin, lithium disilicate cap, RelyX U200 cement and porcelain feldspathic ceramics IPS e.Max (Ivoclar Vivadent). In the second model was designed dentin remaining, silicate cup, RelyX U 200 cement and porcelain. Both models were applied to load of 200 N.Results:The value of maximum tension in the lithium disilicate crown (FEM 1) was obtained was 166.98 Mpa, while in the Zirconium reinforced lithium silicate crown (FEM 2) the maximum tension was 177.6 Mpa. The value of maximum tension on dentin (FEM 1) is 0.27 Mpa and the maximum value (FEM 2) dentin was 0.26 Mpa. The value of maximum tension (FEM 1) on the cervical was 3.93 and (FEM 2) on the cervical was 3.90.Conclusions:The (S.L) crown showed the highest compressive tension in the occlusal and mesial area. In dentin and in the cervical area the compressive tension had similar results. (AU)