Deciphering the enigmatic PilY1 of Acidithiobacillus thiooxidans: An in silico analysis.

Thirty years since the first report on the PilY1 protein in bacteria, only the C-terminal domain has been crystallized; there is no study in which the N-terminal domain, let alone the complete protein, has been crystallized. In our laboratory, we are interested in characterizing the Type IV Pili (T4P) of Acidithiobacillus thiooxidans. We performed an in silico characterization of PilY1 and other pilins of the T4P of this acidophilic bacterium. In silico characterization is crucial for understanding how proteins adapt and function under extreme conditions. By analyzing the primary and secondary structures of proteins through computational methods, researchers can gain valuable insights into protein stability, key structural features, and unique amino acid compositions that contribute to resilience in harsh environments. Here, it is presented a description of the particularities of At. thiooxidans PilY1 through predictor software and homology data. Our results suggest that PilY1 from At. thiooxidans may have the same role as has been described for other PilY1 associated with T4P in neutrophilic bacteria; also, its C-terminal interacts (interface interaction) with the minor pilins PilX, PilW and PilV. The N-terminal region comprises domains such as the vWA and the MIDAS, involved in signaling, ligand-binding, and protein-protein interaction. In fact, the vWA domain has intrinsically disordered regions that enable it to maintain its structure over a wide pH range, not only at extreme acidity to which At. thiooxidans is adapted. The results obtained helped us design the correct methodology for its heterologous expression. This allowed us partially experimentally characterize it by obtaining the N-terminal domain recombinantly and evaluating its acid stability through fluorescence spectroscopy. The data suggest that it remains stable across pH changes. This work thus provides guidance for the characterization of extracellular proteins from extremophilic organisms.

QuantiFERON-TB reversion in children and adolescents with tuberculosis.

We analyzed 136 children with tuberculosis disease or infection and a positive QuantiFERON-TB (QFT) assay, followed-up for a median of 21 months (0.4-11years). QFT reversed in 16.9% of cases, with significant decreases in TB1 (-1.72 vs. -0.03 IU/ml, p=0.001) and TB2 (-1.65 vs. -0.43 IU/ml, p=0.005) levels compared to non-reverters. We found a higher QFT reversion rate among children under 5 years (25.0% vs 11.9%, p=0.042), and those with TST induration <15mm (29% vs 13.3%, p=0.055). Our data reveal that, although QFT test remained positive in the majority of children, reversion occurred in 16% of cases in a progressive and stable pattern. Younger age and reduced TST induration were associated with QFT reversion.

Understanding a Core Pilin of the Type IVa Pili of Acidithiobacillus thiooxidans, PilV.

Pilins are protein subunits of pili. The pilins of type IV pili (T4P) in pathogenic bacteria are well characterized, but anything is known about the T4P proteins in acidophilic chemolithoautotrophic microorganisms such as the genus Acidithiobacillus. The interest in T4P of A. thiooxidans is because of their possible role in cell recruitment and bacterial aggregation on the surface of minerals during biooxidation of sulfide minerals. In this study we present a successful ad hoc methodology for the heterologous expression and purification of extracellular proteins such as the minor pilin PilV of the T4P of A. thiooxidans, a pilin exposed to extreme conditions of acidity and high oxidation-reduction potentials, and that interact with metal sulfides in an environment rich in dissolved minerals. Once obtained, the model structure of A. thiooxidans PilV revealed the core basic architecture of T4P pilins. Because of the acidophilic condition, we carried out in silico characterization of the protonation status of acidic and basic residues of PilV in order to calculate the ionization state at specific pH values and evaluated their pH stability. Further biophysical characterization was done using UV-visible and fluorescence spectroscopy and the results showed that PilV remains soluble and stable even after exposure to significant changes of pH. PilV has a unique amino acid composition that exhibits acid stability, with significant biotechnology implications such as biooxidation of sulfide minerals. The biophysics profiles of PilV open new paradigms about resilient proteins and stimulate the study of other pilins from extremophiles.

Identifying adaptations for a mindfulness program for Spanish-speaking mothers of children with chronic conditions or disabilities.

Mothers of children with chronic conditions or disabilities have benefited from mindfulness programs, yet culturally relevant mindfulness programs for Spanish-speaking mothers are lacking. We aimed to explore how this population experienced a peer-led mindfulness program to inform adaptations. Sixteen mothers attended a 6-week program and completed semi-structured interviews. Using a realist evaluation framework, we explored relationships between participants' context, the program's mechanisms and outcomes. Our thematic analysis found that four contextual factors-faith, self-concept as a woman and mother, trauma, and level of social support-influenced how participants experienced the mechanisms. Mechanisms included having positive experiences when trying practices, engaging in self-reflection, and sharing life experiences and learning in community. The mechanisms led to four outcomes: emotion regulation, savoring daily life experiences, empowerment to practice self-care and common humanity. Faith was an important enabling factor because participants had positive experiences when integrating their faith with program content. Future research should examine adaptations that invite participants to explore this synergy. Self-reflection should also be emphasized because it increased motivation to use practices and helped address barriers to engagement. Because the four contextual factors apply to many Spanish-speaking immigrants, these adaptations could enhance mindfulness programs for this population more broadly.

Disorder and amino acid composition in proteins: their potential role in the adaptation of extracellular pilins to the acidic media, where Acidithiobacillus thiooxidans grows.

There are few biophysical studies or structural characterizations of the type IV pilin system of extremophile bacteria, such as the acidophilic Acidithiobacillus thiooxidans. We set out to analyze their pili-comprising proteins, pilins, because these extracellular proteins are in constant interaction with protons of the acidic medium in which At. thiooxidans grows. We used the web server Operon Mapper to analyze and identify the cluster codified by the minor pilin of At. thiooxidans. In addition, we carried an in-silico characterization of such pilins using the VL-XT algorithm of PONDR® server. Our results showed that structural disorder prevails more in pilins of At. thiooxidans than in non-acidophilic bacteria. Further computational characterization showed that the pilins of At. thiooxidans are significantly enriched in hydroxy (serine and threonine) and amide (glutamine and asparagine) residues, and significantly reduced in charged residues (aspartic acid, glutamic acid, arginine and lysine). Similar results were obtained when comparing pilins from other Acidithiobacillus and other acidophilic bacteria from another genus versus neutrophilic bacteria, suggesting that these properties are intrinsic to pilins from acidic environments, most likely by maintaining solubility and stability in harsh conditions. These results give guidelines for the application of extracellular proteins of acidophiles in protein engineering.

Frecuencia de mordida abierta en niños de 6 a 12 años en escuelas públicas de Gran Asunción en el año 2019

La mordida abierta se define como aquella situación de la oclusión en la que uno o más dientes superiores o inferiores, no alcanzan el plano de la oclusión por no hacer contacto con los antagonistas. El objetivo fue determinar la frecuencia de mordida abierta en niños entre 6 a 12 años de escuelas públicas de Gran Asunción. Estudio descriptivo observacional, de corte transversal que abarcó 1095 niños de ambos sexos, de 6 a 12 años, de escuelas públicas de Gran Asunción- Paraguay en el 2019 que cumplían con los criterios de inclusión. Se realizaron evaluaciones odontológicas para determinar por medio de observación la presencia de mordida abierta y los datos fueron asentados en planillas Excel para su posterior análisis. Del total de 1095 alumnos, 242 presentan mordida abierta (22,1%). El 57,8% presentó mordida abierta anterior, el 35,5% presenta mordida abierta posterior y un 6.6% mordida abierta completa. Los datos que aporta esta investigación contribuyen para implementar y promover tratamientos a edades tempranas, lo que es de vital importancia por las múltiples consecuencias negativas de este tipo de maloclusiones en el niño, debido a que no sólo afecta a la boca, sino también a la funcionalidad de todo el sistema en el cuerpo humano.

Open bite is defined as that occlusion situation in which one or more upper or lower teeth do not reach the occlusion plane because they do not make contact with the antagonists. The objective was to determine the frequency of open bite in children between 6 and 12 years of public schools in Great Asunción. Descriptive observational, cross-sectional study that included 1095 boys and girls from 6 to 12 years old, from public schools in Greater Asunción-Paraguay in 2019 who met the inclusion criteria. Dental evaluations were carried out to determine the presence of open bite by observation and the data was recorded in Excel spreadsheets for later analysis. Of the total of 1095 students, 242 presented open bite (22.1%), 57.8% presented anterior open bite, 35.5% presented posterior open bite and 6.6% complete open bite. The data provided by this research contribute to implement and promote treatments at an early age, which is of vital importance due to the multiple negative consequences of this type of malocclusion in children, because it not only affects the mouth, but also the functionality of the entire system in the human body.

A guide for the administration of oral antineoplastic in patients with swallowing disorders.

OBJECTIVE: To review the available literature on the administration of oral antineoplastic drugs in patients with swallowing disorders and  ystematize the information obtained. METHOD: Between September 2019 and April 2020, two hospital  harmacists drew up a list of the oral antineoplastic drugs available in  Spain, which was then distributed to three hospital pharmacists, each of  whom carried out a literature search and a review. An analysis was made  of the prescribing information and searches were performed in Pubmed, Micromedex, Uptodate, the Cancer Care Ontario website,  different pharmaceutical bulletins, feeding tube administration guidelines,  and tertiary information sources. Lastly, the pharmaceutical industry was  contacted. The group systematized the information obtained, after which a fourth hospital pharmacist and an independent physician reviewed the  work carried out. RESULTS: A total of 64 oral antineoplastic drugs were reviewed. Relevant information was obtained for 48 drugs, of which 44 were  amenable to administration to these patients (69% of the investigated  drugs). A systematization of the information found was carried out. Conclusions: Despite having found different methods for preparing and administering most of the oral antineoplastic drugs reviewed, the  information compiled was rather scarce and with a low level of evidence.  Further studies, based on pharmacokinetic and stability studies, are  necessary in this field as there is a sore need for oral liquid pharmaceutical forms or extemporaneous preparations allowing administration of oral  antineoplastic drugs to these patients.

Objetivo: Revisar la literatura disponible sobre la administración de  antineoplásicos orales en pacientes con trastornos de la deglución y  realizar una síntesis de la información hallada.Método: En el periodo septiembre 2019-junio 2020, tres farmacéuticos hospitalarios elaboraron una lista con los antineoplásicos  orales disponibles en España, la cual fue repartida, y cada cual llevó a  cabo la búsqueda y revisión bibliográfica de los medicamentos asignados.  Se revisaron las fichas técnicas y así como Pubmed, Micromedex,  Uptodate, la página web del Cancer Care Ontario, diferentes boletines  farmacéuticos, guías de administración por sonda y otras fuentes terciarias de información. En último lugar, se contactó con la industria farmacéutica. Posteriormente cada uno sintetizó la información que había  hallado y para concluir, un médico y un cuarto farmacéutico hospitalario  revisaron todo el trabajo llevado a cabo.Resultados: Se revisaron un total de 64 fármacos antineoplásicos orales. Se obtuvo información pertinente en el caso de 48, de los cuales 44  presentaban posibilidad de administración en estos pacientes (un 69% de  los fármacos investigados). Se realizó una síntesis de la información  hallada.Conclusiones: Pese a haber encontrado posibles métodos de preparación y administración para la mayoría de los antineoplásicos orales  revisados, se constata que la información es más bien escasa y con bajo  nivel  de evidencia. Es necesario seguir investigando en este campo, ya  que se precisan formas farmacéuticas líquidas, o preparaciones  extemporáneas, que en base a estudios farmacocinéticos y de estabilidad  permitan la administración de antineoplásicos orales en este grupo de  pacientes.

Biosynthesis of polyhydroxyalkanoates from vegetable oil under the co-expression of fadE and phaJ genes in Cupriavidus necator.

The acyl-CoA dehydrogenase (FadE) and (R)-specific enoyl-CoA hydratase (PhaJ) are functionally related to the degradation of fatty acids and the synthesis of polyhydroxyalkanoates (PHAs). To verify this, a recombinant Cupriavidus necator H16 harboring the plasmid -pMPJAS03- with fadE from Escherichia coli strain K12 and phaJ1 from Pseudomonas putida strain KT2440 under the arabinose promoter (araC-PBAD) was constructed. The impact of co-expressing fadE and phaJ genes on C. necator H16/pMPJAS03 maintaining the wild-type synthase on short-chain-length/medium-chain-length PHA formation from canola or avocado oil at different arabinose concentrations was investigated. The functional activity of fadEE.c led to obtaining higher biomass and PHA concentrations compared to the cultures without expressing the gene. While high transcriptional levels of phaJ1P.p, at 0.1% of arabinose, aid the wild-type synthase to polymerize larger-side chain monomers, such as 3-Hydroxyoctanoate (3HO) and 3-Hydroxydecanoate (3HD). The presence of even small amounts of 3HO and 3HD in the co-polymers significantly depresses the melting temperature of the polymers, compared to those composed of pure 3-hydroxybutyrate (3HB). Our data presents supporting evidence that the synthesis of larger-side chain monomers by the recombinant strain relies not only upon the affinity of the wild-type synthase but also on the functionality of the intermediate supplying enzymes.

[HOSPITALS AS PROMOTERS OF SMOKELESS SPACES: STRATEGIES AIMED AT SMOKING CONTROL] / El hospital como centro promotor de espacios sin humo: estrategias dirigidas al control del tabaquismo.

The objective of this study was to describe the measures introduced at the Hospital Germans Trias i Pujol, Barcelona, aimed at achieving a smoke-free environment, and encouraging research, training, and clinical approaches with respect to smoking. The experience gained as a center attached to the Catalan Network of Smokeless Hospitals since 2002 shows that preventing and controlling smoking requires a specific agenda developed by a competent committee comprising workers from all hospital areas. Likewise, coordination with other centers in the network is essential as it permits the sharing of experiences. The involvement of hospital management is critical for the effective introduction of health protection and promotion strategies, both in workers and in users. The raising of awareness and the ongoing training of all health workers and coordination with other health care providers in the Health network are the main aspects that require strengthening in the future.

El objetivo de este trabajo fue describir las medidas llevadas a cabo en el Hospital Germans Trias i Pujol de Barcelona, destinadas a conseguir un entorno libre de humo, así como al desarrollo de actividades de investigación, formación y abordaje clínico en relación al tabaquismo. La experiencia como centro adherido a la Red Catalana de Hospitales Sin Humo desde 2002 nos revela que para la prevención y control del tabaquismo es necesaria una agenda específica desarrollada por un Comité competente, compuesto por trabajadores de diferentes estamentos y servicios del centro. Del mismo modo, consideramos fundamental la coordinación con otros centros de la Red que permita compartir experiencias, así como la implicación de la Dirección del Centro para la implementación efectiva de las estrategias de promoción y protección de la salud, tanto en los trabajadores como en los usuarios. La sensibilización y formación continuada de todo el personal sanitario y la coordinación con otros servicios proveedores de salud de la red sanitaria se perfilan como los principales puntos a reforzar en el futuro.

Patients with hepatitis C lost to follow-up: ethical-legal aspects and search results.

INTRODUCTION: data on the prevalence and characteristics of hepatitis C patients lost to follow-up are lacking. In addition, the identification of this population clashes with data protection regulations. METHODS: the identification and contact protocol was submitted to the Health Care Ethics Committee. The protocol was based on anti-HCV serology test results for 2010-2018, which were obtained from the Microbiology Department. In addition, the situation of the patients in the hospital and regional database was analyzed, based on the following classification: a) chronic hepatitis C, if the last HCV RNA determination was positive; b) cured hepatitis C, if the last HCV RNA determination was negative after 12 weeks of treatment; and c) possible hepatitis C, if anti-HCV antibodies were positive with no result for HCV RNA. Lost patients were defined as those with chronic or possible hepatitis C and no follow-up in the Digestive Diseases or Internal Medicine Departments. The patients were contacted by postal mail and then by telephone, so that they could be offered treatment. RESULTS: the Ethics Committee considered that the protocol fulfilled the bioethical principles of autonomy, beneficence, non-maleficence and justice and that contact was ethically desirable. From 4,816 positive anti-HCV serology results, 677 patients were identified who were lost to follow-up (14.06 %; 95 % CI, 13.2-15.2). The mean age was 54 years, 61 % were male, 12 % were foreign born and 95 % were mono-infected. The study of each serology result took 1.3 minutes. One-quarter (25 %) of the losses corresponded to the Digestive Diseases and Internal Medicine Departments. Of the 677 losses, serology testing had only been ordered for 449 patients (66.3 %) and the remaining 228 (33.7 %) also had a positive HCV RNA result. CONCLUSION: a large number of patients with hepatitis C are lost to follow-up. Searching for and contacting these patients is legally and ethically viable.

Inhibition of Kv10.1 Channels Sensitizes Mitochondria of Cancer Cells to Antimetabolic Agents.

Reprogramming of energy metabolism constitutes one of the hallmarks of cancer and is, therefore, an emerging therapeutic target. We describe here that the potassium channel Kv10.1, which is frequently overexpressed in primary and metastatic cancer, and has been proposed a therapeutic target, participates in metabolic adaptation of cancer cells through regulation of mitochondrial dynamics. We used biochemical and cell biological techniques, live cell imaging and high-resolution microscopy, among other approaches, to study the impact of Kv10.1 on the regulation of mitochondrial stability. Inhibition of Kv10.1 expression or function led to mitochondrial fragmentation, increase in reactive oxygen species and increased autophagy. Cells with endogenous overexpression of Kv10.1 were also more sensitive to mitochondrial metabolism inhibitors than cells with low expression, indicating that they are more dependent on mitochondrial function. Consistently, a combined therapy using functional monoclonal antibodies for Kv10.1 and mitochondrial metabolism inhibitors resulted in enhanced efficacy of the inhibitors. Our data reveal a new mechanism regulated by Kv10.1 in cancer and a novel strategy to overcome drug resistance in cancers with a high expression of Kv10.1.

Quality of life study in asymptomatic patients with hepatitis C.

OBJECTIVE AND METHODS: an observational, longitudinal, prospective study was performed to assess changes in perceived quality of life in asymptomatic patients with hepatitis C under treatment with direct-acting antivirals. Questionnaires SF-36 and EQ-5D-5L were administered to 86 treated patients and 12 controls. RESULTS: there were improvements in several parameters such as physical functioning, bodily pain, general health, vitality and social functioning, particularly when the perceptions were compared before treatment and after treatment completion and following recovery. CONCLUSION: these data support the hypothesis that the hepatitis C virus may worsen quality of life in asymptomatic patients.

Análogos de prostaglandinas I2 (epoprostenol y treprostinil) para el tratamiento de la hipertensión pulmonar refractaria secundaria a displasia broncopulmonar en un lactante / Prostaglandin 12 analogs (epoprostenol and treprostinil) as a treatment for refractory bronchopulmonary dysplasia-induced pulmonary hypertension in an infant

La hipertensión pulmonar es una complicación frecuente de la displasia broncopulmonar. A pesar de su alta incidencia, existen pocos tratamientos disponibles. El epoprostenol y el treprostinil son análogos de las prostaglandinas I2, que activan la adenilato ciclasa e incrementan el adenosín monofosfato cíclico en las células de la musculatura lisa de la arteria pulmonar y pueden resultar eficaces en el tratamiento de estos pacientes. Se presenta el caso de un prematuro de extremado bajo peso con hipertensión pulmonar secundaria a displasia broncopulmonar grave, no respondedora a óxido nítrico inhalado y sildenafilo, que fue tratado con análogos de prostaglandinas I2. En nuestro paciente, este tratamiento evidenció mejoría clínica y ecocardiográfica significativa tras varias semanas de tratamiento.

Pulmonary hypertension is a common complication of bronchopulmonary dysplasia, with a high mortality rate. Despite the high incidence of pulmonary hypertension, there are few available treatments. Epoprostenol and treprostinil are prostaglandin I2 analogs that activate adenylate cyclase and increase cyclic adenosine monophosphate in the pulmonary arterial smooth muscle cells. Therefore, they may be an effective treatment for these patients. We report the use of prostaglandin I2 analogs in an extremely low birth weight preterm baby with severe bronchopulmonary dysplasia associated with pulmonary hypertension non-responding to inhaled nitric oxide and sildenafil. In our patient this treatment resulted in remarkable clinical and echocardiographic improvement, evident after a few weeks of treatment.

[Prostaglandin 12 analogs (epoprostenol and treprostinil) as a treatment for refractory bronchopulmonary dysplasia-induced pulmonary hypertension in an infant]. / Análogos de prostaglandinas I2 (epoprostenol y treprostinil) para el tratamiento de la hipertensión pulmonar refractaria secundaria a displasia broncopulmonar en un lactante.

Pulmonary hypertension is a common complication of bronchopulmonary dysplasia, with a high mortality rate. Despite the high incidence of pulmonary hypertension, there are few available treatments. Epoprostenol and treprostinil are prostaglandin I2 analogs that activate adenylate cyclase and increase cyclic adenosine monophosphate in the pulmonary arterial smooth muscle cells. Therefore, they may be an effective treatment for these patients. We report the use of prostaglandin I2 analogs in an extremely low birth weight preterm baby with severe bronchopulmonary dysplasia associated with pulmonary hypertension non-responding to inhaled nitric oxide and sildenafil. In our patient this treatment resulted in remarkable clinical and echocardiographic improvement, evident after a few weeks of treatment.

La hipertensión pulmonar es una complicación frecuente de la displasia broncopulmonar. A pesar de su alta incidencia, existen pocos tratamientos disponibles. El epoprostenol y el treprostinil son análogos de las prostaglandinas I2, que activan la adenilato ciclasa e incrementan el adenosín monofosfato cíclico en las células de la musculatura lisa de la arteria pulmonar y pueden resultar eficaces en el tratamiento de estos pacientes. Se presenta el caso de un prematuro de extremado bajo peso con hipertensión pulmonar secundaria a displasia broncopulmonar grave, no respondedora a óxido nítrico inhalado y sildenafilo, que fue tratado con análogos de prostaglandinas I2. En nuestro paciente, este tratamiento evidenció mejoría clínica y ecocardiográfica significativa tras varias semanas de tratamiento.

Sequence analysis and confirmation of the type IV pili-associated proteins PilY1, PilW and PilV in Acidithiobacillus thiooxidans.

Acidithiobacillus thiooxidans is an acidophilic chemolithoautotrophic bacterium widely used in the mining industry due to its metabolic sulfur-oxidizing capability. The biooxidation of sulfide minerals is enhanced through the attachment of At. thiooxidans cells to the mineral surface. The Type IV pili (TfP) of At. thiooxidans may play an important role in the bacteria attachment since TfP play a key adhesive role in the attachment and colonization of different surfaces. In this work, we report for the first time the mRNA sequence of three TfP proteins from At. thiooxidans, the adhesin protein PilY1 and the TfP pilins PilW and PilV. The nucleotide sequences of these TfP proteins show changes in some nucleotide positions with respect to the corresponding annotated sequences. The bioinformatic analyses and 3D-modeling of protein structures sustain their classification as TfP proteins, as structural homologs of the corresponding proteins of Ps. aeruginosa, results that sustain the role of PilY1, PilW and PilV in pili assembly. Also, that PilY1 comprises the conserved Neisseria-PilC (superfamily) domain of the tip-associated adhesin, while PilW of the superfamily of putative TfP assembly proteins and PilV belongs to the superfamily of TfP assembly protein. In addition, the analyses suggested the presence of specific functional domains involved in adhesion, energy transduction and signaling functions. The phylogenetic analysis indicated that the PilY1 of Acidithiobacillus genus forms a cohesive group linked with iron- and/or sulfur-oxidizing microorganisms from acid mine drainage or mine tailings.

Tratamiento de recesiones gingivales múltiples clase I y III de Miller combinando injerto de tejido conectivo sub-epitelial con técnica en túnel / Treatment of multiple Miller class I and III gingival recessions by means of sub-epithelial connective tissue graft and tunnel technique

Resumen Introducción: La recesión gingival puede estar relacionada con la enfermedad periodontal o condiciones mucogingivales ocasionando hipersensibilidad, caries radicular y problemas estéticos. La combinación de la técnica en túnel y el injerto de tejido conectivo subepitelial puede considerarse una opción para el tratamiento de recesiones gingivales múltiples. Presentación del caso: Paciente de sexo femenino de 38 años de edad, al interrogatorio refiere tener hipersensibilidad dentaria en los dientes superiores (13, 14, 22, 23, 24) que presentan recesión gingival. A la valoración periodontal se observan recesiones gingivales clase I y III de Miller en cuadrante I y II, el diagnóstico periodontal es periodonto sano. Para realizar la cobertura radicular se planea combinar la colocación de injerto de tejido conectivo subepitelial con técnica en túnel, siendo un procedimiento adecuado cuando las papilas interdentales son amplias, además de ser una técnica de alta predictibilidad para lograr la cobertura radicular. En este caso, se decidió iniciar por el segundo cuadrante, ya que eran los sitios con mayor hipersensibilidad dentaria y un mes después realizar el tratamiento en el primer cuadrante. Conclusiones: La técnica que se aplicó permitió eliminar la hipersensibilidad dentaria en un 100% considerando como única desventaja el doble sitio quirúrgico del sitio donador. Es importante mencionar que además de lograr mejoría en la hipersensibilidad dentaria, se mejoraron las condiciones estéticas.

Abstract Introduction: Gingival recession can be associated to periodontal disease or muco-gingival conditions causing hypersensitivity, root caries and esthetic problems. A combination of the tunneling technique with sub-epithelial connective tissue graft can be considered an option for multiple gingival recession treatment. Case presentation: A 38 year old female patient who informed of suffering hypersensitivity in upper teeth (13, 14, 22, 23, 24), exhibiting gingival recession. Periodontal evaluation revealed Miller class I and III gingival recessions in quadrants I and II. Periodontal diagnosis was healthy periodontium. In order to achieve root coverage, placement of sub-epithelial connective tissue graft with tunneling was planned. This represents a suitable procedure in cases when interdental papillae are wide, moreover, it constitutes a high predictability technique in order to achieve root coverage. In the present case, it was decided to initiate treatment on the second quadrant since it lodged sites with greater dental hypersensitivity, to be followed a month later by treatment on the first quadrant. Conclusions: This applied technique allowed for 100% elimination of tooth hypersensitivity, only considering a disadvantage the double surgical site of the donor site. It is important to mention that, in addition to achieving improvement in tooth hypersensitivity, esthetic appearance was improved.

The electric fence to cell-cycle progression: Do local changes in membrane potential facilitate disassembly of the primary cilium?: Timely and localized expression of a potassium channel may set the conditions that allow retraction of the primary cilium.

Kv10.1 is a voltage-gated potassium channel relevant for tumor biology, but the underlying mechanism is still unclear. We propose that Kv10.1 plays a role coordinating primary cilium disassembly with cell cycle progression through localized changes of membrane potential at the ciliary base. Most non-dividing cells display a primary cilium, an antenna-like structure important for cell physiology. The cilium is disassembled when the cell divides, which requires an increase of Ca2+ concentration and a redistribution of phospholipids in its basal region, both of which would be facilitated by local hyperpolarization. Cells lacking Kv10.1 show impaired ciliary disassembly and delayed entrance into mitosis. Kv10.1 is predominantly expressed during G2/M, a critical period for ciliary resorption, and localizes to the ciliary base and vesicles associated with the centrosome. This could explain the influence of Kv10.1 in cell proliferation, as well as phenotypic features of patients carrying gain of function mutations in the gene.

Cyclic expression of the voltage-gated potassium channel KV10.1 promotes disassembly of the primary cilium.

The primary cilium, critical for morphogenic and growth factor signaling, is assembled upon cell cycle exit, but the links between ciliogenesis and cell cycle progression are unclear. KV10.1 is a voltage-gated potassium channel frequently overexpressed in tumors. We have previously reported that expression of KV10.1 is temporally restricted to a time period immediately prior to mitosis in healthy cells. Here, we provide microscopical and biochemical evidence that KV10.1 localizes to the centrosome and the primary cilium and promotes ciliary disassembly. Interference with KV10.1 ciliary localization abolishes not only the effects on ciliary disassembly, but also KV10.1-induced tumor progression in vivo Conversely, upon knockdown of KV10.1, ciliary disassembly is impaired, proliferation is delayed, and proliferating cells show prominent primary cilia. Thus, modulation of ciliogenesis by KV10.1 can explain the influence of KV10.1 expression on the proliferation of normal cells and is likely to be a major mechanism underlying its tumorigenic effects.

Hepatitis B and D viruses replication interference: Influence of hepatitis B genotype.

AIM: To study the hepatitis B virus (HBV) and hepatitis D virus (HDV) replication interferences in patients with chronic hepatitis delta infected with different HBV genotypes. METHODS: We conducted a transversal study including 68 chronic hepatitis delta (CHD) (37 HIV-positive) patients and a control group of 49 chronic hepatitis B (CHB) (22 HIV-positive) patients. In addition, a dynamic follow-up was performed in 16 CHD patients. In all the samples, the surface antigen of hepatitis B (HBsAg) serum titers were analyzed with the Monolisa HBsAg Ultra system (Bio-Rad), using as quantification standard a serial dilution curve of an international HBsAg standard. Serum HBV-DNA titers were analyzed using the Roche Cobas TaqMan (Roche, Barcelona, Spain), and the serum HDV-RNA using an in-house real-time qRT-PCR method, with TaqMan probes. HBV genotype was determined with the line immunoassay LiPA HBV genotyping system (Innogenetics, Ghent, Belgium). In those patients negative for LiPA assay, a nested PCR method of complete HBsAg coding region, followed by sequence analysis was applied. RESULTS: No differences in the HBV-DNA levels were found in CHB patients infected with different HBV genotypes. However, in CHD patients the HBV-DNA levels were lower in those infected with HBV-A than in those with HBV-D, both in HIV negative [median (IQR): 1.25 (1.00-1.35) vs 2.95 (2.07-3.93) log10 (copies/mL), P = 0.013] and HIV positive patients [2.63 (1.24-2.69) vs 7.25 (4.61-7.55) log10 (copies/mL), P < 0.001]. This was confirmed in the dynamic study of the HBV/HDV patients. These differences induce an under-estimation of HBV-A incidence in patients with CHD analyzed with LiPA assay. Finally, the HBsAg titers reflected no significant differences in CHD patients infected with HBV-A or D. CONCLUSION: Viral replication interference between HBV and HDV is HBV-genotype dependent, and more evident in patients infected with HBV-genotype A, than with HBV-D or E.

Synthesis and activity of novel 16-dehydropregnenolone acetate derivatives as inhibitors of type 1 5α-reductase and on cancer cell line SK-LU-1.

Testosterone (T) plays a crucial role in prostate growth. In androgen-dependent tissues T is reduced to dihydrotestosterone (DHT) because of the presence of the 5α-reductase enzyme. This androgen is more active than T, since it has a higher affinity for the androgen receptor (AR). When this mechanism is altered, androgen-dependent diseases, including prostate cancer, could result. The aim of this study was to synthesize several 16-dehydropregnenolone acetate derivatives containing a triazole ring at C-21 and a linear or alicyclic ester moiety at C-3 of the steroidal skeleton. These steroids were designed as potential inhibitors of the activity of both types (1 and 2) of 5α-reductase. The cytotoxic activity of these compounds was also evaluated on a panel of PC-3, MCF7, and SK-LU-1 human cancer cell lines. The results from this study showed that with the exception of steroids 20-oxo-21-(1H-1,2,4-triazole-1-yl)pregna-5,16-dien-3ß-yl-propionate and 20-oxo-21-(1H-1,2,4-triazole-1-yl)pregna-5,16-dien-3ß-yl-pentanoate, the compounds exhibit a lower inhibitory activity for both isoenzymes of 5α-reductase than finasteride. Furthermore the 3ß-hydroxy-21-(1H-1,2,4-triazole-1-yl)pregna-5,16-dien-20-one and 20-oxo-21-(1H-1,2,4-triazole-1-yl)pregna-5,16-dien-3ß-yl-acetate derivatives display 80% cytotoxic activity on the SK-LU-1 cell line. These results also indicated that the triazole derivatives, which have a hydroxyl or acetoxy group at C-3, could have an anticancer effect, whereas the derivatives with a alicyclic ester group at C-3 do not show biological activity.