Small Synthetic Hyaluronan Disaccharide BIS014 Mitigates Neuropathic Pain in Mice.

Neuropathic pain (NP) is a challenging condition to treat, as the need for new drugs to treat NP is an unmet goal. We investigated the analgesic potential of a new sulfated disaccharide compound, named BIS014. Oral administration (p.o.) of this compound induced ameliorative effects in formalin-induced nociception and capsaicin-induced secondary mechanical hypersensitivity in mice, but also after partial sciatic nerve transection (spared nerve injury), chemotherapy (paclitaxel)-induced NP, and diabetic neuropathy induced by streptozotocin. Importantly, BIS014, at doses active on neuropathic hypersensitivity (60 mg/kg/p.o.), did not alter exploratory activity or motor coordination (in the rotarod test), unlike a standard dose of gabapentin (40 mg/kg/p.o.) which although inducing antiallodynic effects on the NP models, it also markedly decreased exploration and motor coordination. In docking and molecular dynamic simulation studies, BIS014 interacted with TRPV1, a receptor involved in pain transmission where it behaved as a partial agonist. Additionally, similar to capsaicin, BIS014 increased cytosolic Ca2+ concentration ([Ca2+]c) in neuroblastoma cells expressing TRPV1 receptors; these elevations were blocked by ruthenium red. BIS014 did not block capsaicin-elicited [Ca2+]c transients, but inhibited the increase in the firing rate of action potentials in bradykinin-sensitized dorsal root ganglion neurons stimulated with capsaicin. Perspective: We report that the oral administration of a new sulfated disaccharide compound, named BIS014, decreases neuropathic pain from diverse etiology in mice. Unlike the comparator gabapentin, BIS014 does not induce sedation. Thus, BIS014 has the potential to become a new efficacious non-sedative oral medication for the treatment of neuropathic pain.

Aprotinin treatment against SARS-CoV-2: A randomized phase III study to evaluate the safety and efficacy of a pan-protease inhibitor for moderate COVID-19.

BACKGROUND: SARS-CoV-2 virus requires host proteases to cleave its spike protein to bind to its ACE2 target through a two-step furin-mediated entry mechanism. Aprotinin is a broad-spectrum protease inhibitor that has been employed as antiviral drug for other human respiratory viruses. Also, it has important anti-inflammatory properties for inhibiting the innate immunity contact system. METHODS: This was a multicentre, double-blind, randomized trial performed in four Spanish hospitals comparing standard treatment versus standard treatment + aprotinin for patients with COVID-19 between 20 May 2020 and 20 October 2021. The primary efficacy outcomes were length of hospital stay and ICU admission. The secondary endpoints were each of the primary efficacy outcomes and a composite of oxygen therapy, analytical parameters and death. Safety outcomes included adverse reactions to treatment during a 30-day follow-up period. Treatment was given for 11 days or till discharge. RESULTS: With almost identical analytical profiles, significant differences were observed in treatment time, which was 2 days lower in the aprotinin group (p = .002), and length of hospital admission, which was 5 days shorter in the aprotinin group (p = .003). The incidence of discharge was 2.19 times higher (HR: 2.188 [1.182-4.047]) in the aprotinin group than in the placebo group (p = .013). In addition, the aprotinin-treated group required less oxygen therapy and had no adverse reactions or side effects. CONCLUSION: Inhaled aprotinin may improve standard treatment and clinical outcomes in hospitalized patients with COVID-19, resulting in a shorter treatment time and hospitalization compared with the placebo group. The administration of aprotinin was safe.

Progressive Mitochondrial SOD1G93A Accumulation Causes Severe Structural, Metabolic and Functional Aberrations through OPA1 Down-Regulation in a Mouse Model of Amyotrophic Lateral Sclerosis.

In recent years, the "non-autonomous motor neuron death" hypothesis has become more consolidated behind amyotrophic lateral sclerosis (ALS). It postulates that cells other than motor neurons participate in the pathology. In fact, the involvement of the autonomic nervous system is fundamental since patients die of sudden death when they become unable to compensate for cardiorespiratory arrest. Mitochondria are thought to play a fundamental role in the physiopathology of ALS, as they are compromised in multiple ALS models in different cell types, and it also occurs in other neurodegenerative diseases. Our study aimed to uncover mitochondrial alterations in the sympathoadrenal system of a mouse model of ALS, from a structural, bioenergetic and functional perspective during disease instauration. We studied the adrenal chromaffin cell from mutant SOD1G93A mouse at pre-symptomatic and symptomatic stages. The mitochondrial accumulation of the mutated SOD1G93A protein and the down-regulation of optic atrophy protein-1 (OPA1) provoke mitochondrial ultrastructure alterations prior to the onset of clinical symptoms. These changes affect mitochondrial fusion dynamics, triggering mitochondrial maturation impairment and cristae swelling, with increased size of cristae junctions. The functional consequences are a loss of mitochondrial membrane potential and changes in the bioenergetics profile, with reduced maximal respiration and spare respiratory capacity of mitochondria, as well as enhanced production of reactive oxygen species. This study identifies mitochondrial dynamics regulator OPA1 as an interesting therapeutic target in ALS. Additionally, our findings in the adrenal medulla gland from presymptomatic stages highlight the relevance of sympathetic impairment in this disease. Specifically, we show new SOD1G93A toxicity pathways affecting cellular energy metabolism in non-motor neurons, which offer a possible link between cell specific metabolic phenotype and the progression of ALS.

Chronic resveratrol consumption prevents hypertension development altering electrophysiological currents and Ca2+ signaling in chromaffin cells from SHR rats.

Resveratrol (RESV) is one of the most abundant polyphenol-stilbene compounds found in red wine with well-established cardioprotective and antihypertensive effects. Hyperactivity of the sympathoadrenal axis seems to be one of the major contributing factors in the pathogenesis of human essential hypertension. Alterations in outward voltage-dependent potassium currents (IK) and inward voltage-dependent sodium (INa), calcium (ICa) and nicotinic (IACh) currents, CCs excitability, Ca2+ homeostasis, and catecholamine exocytosis were previously related to the hypertensive state. This raised the issue of whether in vivo long-term RESV treatment can directly act as a modulator of Ca2+ influx or a regulator of ion channel permeability in CCs. We monitored outward and inward currents, and cytosolic Ca2+ concentrations ([Ca2+]c) using different pharmacological approaches in CCs from normotensive (WKY) and hypertensive (SHR) animals chronically exposed to trans-RESV (50 mg/L/v.o, 28 days). The long-term RESV treatment prevented the increase of the systolic blood pressure (SBP) in SHR, without reversion of cardiac hypertrophy. We also found an increase of the outward IK, reduction in inward INa,ICa, and IACh, and the mitigation of [Ca2+]c overload in CCs from SHR at the end of RESV treatment. Our data revealed that electrophysiological alterations of the CCs and in its Ca2+ homeostasis are potential new targets related to the antihypertensive effects of long-term RESV treatment.

Function of AT1 and AT2 receptors in atrial contractions from spontaneous hypertensive and diabetic-induced streptozotocin rats.

Diabetes mellitus and hypertension are diseases that are strongly correlated. A major factor in this correlation is the renin-angiotensin system (RAS), with the peptide angiotensin II being a key component. This study analyzed the impact of Angiotensin Type 1 receptor (AT1R) and Angiotension Type 2 receptor (AT2R) in atrial function. MAIN METHODS: To perform the experiments, Wistar Kyoto rats (WKY), diabetic streptozotocin-induced WKY rats and spontaneously hypertensive rats (SHR) were used, and stimulation of cardiovascular function was done by means of the following drugs: angiotensin II, novokinin and the antagonists losartan and PD123177. We also measured the systolic blood pressure (SBP). RESULTS: An increase in AT1R function was observed in diabetic and hypertensive rats (18% in right atria [RA] and 11% in left atria [LA]). We also observed an increase in calcium release from the endoplasmic reticulum in right atria of diabetic rats (31%) and in right atria of hypertensive rats (35%). On the other hand, a decreased response of AT2R in diabetic and hypertensive rats was observed, this decreased response was greater in hypertensive rats (RA, 10%; LA, 12%). These results have demonstrated a dysfunction of the RAS that may contribute to the common dysfunctions of the cardiovascular system in diabetic and hypertensive rats.

Diverticulitis cecal: un complejo desafío médico / Cecal diverticulitis: a complex medical challenge

Antecedentes: la diverticulitis cecal es una patología poco común en los países occidentales. Clínicamente es indistinguible de una apendicitis aguda. Objetivos: exhibir los resultados de acuerdo con diferentes abordajes terapéuticos. Material y métodos: se presentan cinco casos de diverticulitis cecal tratados en nuestra institución entre enero de 2013 y diciembre de 2015. Revisión retrospectiva de historias clínicas e imágenes. Revisión de la literatura. Resultados: fueron incluidos cinco pacientes. En cuatro hubo resolución quirúrgica y uno tuvo buena evolución con tratamiento médico. Conclusiones: si bien es poco frecuente, la diverticulitis cecal debe considerarse dentro de los diagnósticos diferenciales frente a un cuadro de dolor abdominal localizado en fosa ilíaca derecha acompañado de estudios por imágenes no categóricos de apendicitis aguda.

Background: cecal diverticulitis is a rare disease in western countries. It is clinically indistinguishable from acute appendicitis. Objetive: to show outcome with different therapeutic approaches. Material and methods: we present five cases of cecal diverticulitis treated at our institution between January 2013 and December 2015. Retrospective review of medical records and images. Review of the literature. Results: five patients were included. Four cases required surgical treatment while one patient resolved with medical treatment. Conclusions: Although it is rare, cecal diverticulitis must be considered within the differential diagnoses in the face of abdominal pain located in the right iliac fossa and non-categorical imaging of acute appendicitis.

Altered mitochondrial function, calcium signaling, and catecholamine release in chromaffin cells of diabetic and SHR rats.

Comorbidity of diabetes and hypertension is frequent. Here, we have performed a comparative study in three animal models namely, normotensive Wistar Kyoto (WKY) rats, streptozotocin-induced diabetic rats (STZ), and spontaneously hypertensive rats (SHR). With respect WKY rats, we have found the following alterations in adrenal chromaffin cells from STZ and SHR rats: (1) diminished Ca2+ currents; (2) augmented [Ca2+]c elevations and catecholamine release in cells stimulated with angiotensin II or high K+; (3) unchanged expression of angiotensin II receptors AT1 and AT2; (4) higher density of secretory vesicles at subplasmalemmal sites; (5) mitochondria with lower cristae density that were partially depolarized; and (6) lower whole cell ATP content. These alterations may have their origin in (i) an augmented capacity of the endoplasmic reticulum [Ca2+] store likely due to (ii) impaired mitochondrial Ca2+ uptake; (iii) augmented high-[Ca2+]c microdomains at subplasmalemmal sites secondary to augmented calcium-induce calcium release and to inositol tris-phosphate receptor mediated enhanced Ca2+ mobilization from the endoplasmic reticulum; and (iv) augmented vesicle pool. These alterations seem to be common to the two models of human hypertension here explored, STZ diabetic rats and SHR hypertensive rats.

The Stimulated Glycolytic Pathway Is Able to Maintain ATP Levels and Kinetic Patterns of Bovine Epididymal Sperm Subjected to Mitochondrial Uncoupling.

Studies have reported the importance of mitochondria in sperm functionality. However, for some species, the glycolytic pathway appears to be as important as oxidative phosphorylation in ATP synthesis and sperm kinetics. These mechanisms have not been fully elucidated for bovine spermatozoa. Therefore, the aim of this study was to evaluate the role of mitochondria and the glycolytic pathway in ATP synthesis, sperm movement patterns, and oxidative homeostasis of epididymal spermatozoa in bovine specimens. We observed that mitochondrial uncoupling with protonophores significantly reduced ATP levels. However, these levels were reestablished after stimulation of the glycolytic pathway. We verified the same pattern of results for sperm kinetic variables and the production of reactive oxygen species (ROS). Thus, we suggest that, after its appropriate stimulation, the glycolytic pathway is capable of maintaining ATP levels, sperm kinetic patterns, and oxidative balance of bovine epididymal spermatozoa submitted to mitochondrial uncoupling.

Electrophysiological properties and augmented catecholamine release from chromaffin cells of WKY and SHR rats contributing to the hypertension development elicited by chronic EtOH consumption.

It is known that chronic ethanol (EtOH) consumption leads to hypertension development and has been associated with deleterious effects on the cardiovascular system. Whether this condition alters calcium (Ca2+) signaling and exocytosis in adrenal chromaffin cells (CCs) as the case is for genetic hypertension, is unknown. We explored this question in four randomized experimental groups, male Wistar Kyoto (WKY/EtOH) and Spontaneously Hypertensive (SHR/EtOH) rats were subjected to the intake of increasing EtOH concentrations (5-20%, for 30 days) and their respective controls (WKY/Control and SHR/Control) received water. WKY/EtOH developed hypertension and cardiac hypertrophy; blood aldehyde dehydrogenase (ALDH) and H2O2 were also augmented. In comparison with WKY/Control, CCs from WKY/EtOH had the following features: (i) depolarization and higher frequency of spontaneous action potentials; (ii) decreased Ca2+ currents with slower inactivation; (iii) decreased K+ currents; (iv) augmented K+-elicited cytosolic Ca2+ transients ([Ca2+]c); (v) enhanced K+-elicited catecholamine release. These cardiovascular, blood and CCs changes were qualitatively similar to those undergone by SHR/Control and SHR/EtOH. The results suggest that the hypertension elicited by chronic EtOH has pathogenic features common to genetic hypertension namely, augmented [Ca2+]c transients and catecholamine release from their CCs.

Functional Upregulation of STIM-1/Orai-1-Mediated Store-Operated Ca2+ Contributing to the Hypertension Development Elicited by Chronic EtOH Consumption.

BACKGROUND: Chronic ethanol (EtOH) consumption has been associated with deleterious effects on the cardiovascular system by abnormal calcium (Ca2+) handling. Store-operated Ca2+ entry (SOCE) is related to cardiovascular remodeling which leads to the hypertension development, and the coupling between STIM-1 (ER Ca2+ sensor) and Orai-1 (channel pore) is a key mechanism to control SOCE through of store-operated Ca2+ channels (SOCCs). However, the role of STIM-1/Orai-1-mediated SOCE and its cross-talk with EtOH-triggered vascular remodeling and hypertension remain poorly understood. We address this subject in the present study by evaluating how chronic EtOH consumption induces alterations in Ca2+ handling via SOCE. METHODS: Male Wistar Kyoto (WKY) and Spontaneously Hypertensive (SHR) rats were subjected to the intake of increasing EtOH concentrations (5-20%, for 30 days). Systolic blood pressure (SBP) and EtOH concentration were measured; cardiovascular remodeling was assessed by histomorphometry; and function/ expression of STIM-1/Orai-1-mediated Ca2+ influx were evaluated by isometric contraction and western blot experiments. RESULTS: Compared to the WKY-Control, our results show that: (1) chronic EtOH consumption caused a significant elevation of SBP in both strains; (2) cardiac hypertrophy and hypertrophic aortic wall remodeling much more pronounced in WKY-EtOH; (3) decreased capacity of ER to store and release Ca2+; (4) increased STIM-1/Orai-1-mediated SOCCs activation, which was selectively inhibited by YM-58483; and (5) increased expression of STIM-1 in WKY-EtOH and SHR-Control rats. CONCLUSION: These findings suggest that hypertrophic aortic remodeling and abnormal contraction triggered mainly by Ca2+ overload via STIM-1/Orai-1-mediated SOCE through SOCCs are involved hypertension developed by EtOH consumption.

Faster kinetics of quantal catecholamine release in mouse chromaffin cells stimulated with acetylcholine, compared with other secretagogues.

Adrenal chromaffin cells (CCs) have been used extensively in studies aimed at revealing the intricacies of the Ca2+ -dependent early and late steps of regulated exocytosis. They have also served as invaluable models to study the kinetics of single-vesicle exocytotic events to infer the characteristics of opening and closing of the exocytotic fusion pore. We have here tested the hypothesis that stimulation at room temperature of CCs from mice C57BL/6 with physiological acetylcholine (ACh) and with other secretagogues (dimethylphenylpiperazinium, high K+ , muscarine, histamine, caffeine), alone or in combination, could trigger amperometric spike events with different kinetics. We found that mean secretory spike events in CCs stimulated with ACh had a fast rise rate of 25 pA/ms and a rapid decay time of 6.2 ms, with a small quantal size (0.31 pC). Surprisingly, these parameters considerably differed from those found in CCs stimulated with all other secretagogues that triggered secretory responses with spike events having smaller rise rates, longer decay times and higher quantal sizes. ACh spikes were unaltered by atropine but mitochondrial protonophore carbonyl cyanide-4-(trifluoromethoxy)phenylhydrazone markedly slowed down the rate rise and decay time, and augmented the quantal size of mean secretory events. We conclude that the physiological neurotransmitter ACh triggers a fast and efficient exocytotic response that cannot be mimicked by other secretagogues; such response is regulated by the mitochondrial circulation of calcium ions.

Capacitación estratégica e inductiva en cuidados de heridas para enfermeros domiciliarios / Strategic and inductive wound care training for homecare nurses

Objetivos: Asegurar el uso de la Guía Institucional para los cuidados de úlceras por presión y la adecuada inducción de los profesionales de reciente ingreso. Metodología: Estudio descriptivo retrospectivo aleatorio aplicado a la dotación de enfermería humano en sistemas tegumentarios y piel, implementando las innovaciones tecnológicas disponibles. Resultados: n: 43 prestaciones (cuidados de úlceras por presión). Alumnado: 52 enfermeros asistenciales como recurso humano eje de capacitación. En la cohorte auditada se evaluó la instrumentación de la Guía Institucional por parte de los profesionales de medicina domiciliaria del Hospital Italiano de Buenos Aires, Argentina, en el que se utilizó una esfera pragmática, mediante la cual se capacitó al recurso. Conclusiones: Se concluye el programa educativo, con el que se obtiene un alto porcentaje de instrumentación adecuada de la guía hospitalaria por parte de los educandos (promedio porcentual 98,8%) y se expone una efectiva inducción para los profesionales de reciente ingreso

Objectives: To ensure the use of the Institutional Guidelines for pressure ulcer care and proper induction of newly recruited professionals. Methodology: A randomized retrospective descriptive study applied to the Nursing Ambulatory Medicine Staff of the Hospital Italiano of Buenos Aires, Argentina, in which by a pragmatic sphere, human resources were trained in tegumentary systems and skin, implementing innovating available technology. Results: n: 43 benefits (care of pressure ulcers). Students: 52 clinical nurses as human resource training axis. In the audited cohort instrumentation of Institutional Guide by professionals was evaluated. Conclusions: We conclude the Educational Program, obtaining a high percentage of suitable instrumentation of hospital guide by learners (average percentage 98.8%) and an effective induction of professionals of recent entry

Novel synthetic sulfoglycolipid IG20 facilitates exocytosis in chromaffin cells through the regulation of sodium channels.

In search of druggable synthetic lipids that function as potential modulators of synaptic transmission and plasticity, we synthesized sulfoglycolipid IG20, which stimulates neuritic outgrowth. Here, we have explored its effects on ion channels and exocytosis in bovine chromaffin cells. IG20 augmented the rate of basal catecholamine release. Such effect did not depend on Ca(2+) mobilization from intracellular stores; rather, IG20-elicited secretion entirely dependent on Ca(2+) entry through L-subtype voltage-activated Ca(2+) channels. Those channels were recruited by cell depolarization mediated by IG20 likely through its ability to enhance the recruitment of Na(+) channels at more hyperpolarizing potentials. Confocal imaging with fluorescent derivative IG20-NBD revealed its rapid incorporation and confinement into the plasmalemma, supporting the idea that IG20 effects are exerted through a plasmalemmal-delimited mechanism. Thus, synthetic IG20 seems to mimic several physiological effects of endogenous lipids such as regulation of ion channels, Ca(2+) signaling, and exocytosis. Therefore, sulfoglycolipid IG20 may become a pharmacological tool for investigating the role of the lipid environment on neuronal excitability, ion channels, neurotransmitter release, synaptic efficacy, and neuronal plasticity. It may also inspire the synthesis of druggable sulfoglycolipids aimed at increasing synaptic plasticity and efficacy in neurodegenerative diseases and traumatic brain-spinal cord injury. The novel synthetic sulfoglycolipid IG20 mimics several physiological effects of endogenous lipids such as regulation of ion channels, Ca(2+) signaling, and exocytosis. This profile may eventually drive enhanced synaptic plasticity and efficacy.

Calcium Channel Subtypes and Exocytosis in Chromaffin Cells at Early Life.

Here we review the contribution of the various subtypes of voltage-activated calcium channels (VACCs) to the regulation of catecholamine release from chromaffin cells (CCs) at early life. Patch-clamp recording of inward currents through VACCs has revealed the expression of high-threshold VACCs (high-VACCs) of the L, N, and PQ subtypes in rat embryo CCs and ovine embryo CCs. Low-threshold VACC (low-VACC) currents (T-type) have also been recorded in rat embryo CCs and rat neonatal slices of adrenal medullae. Near full blockade by nifedipine and nimodipine of the K(+)-elicited secretion as well as the hypoxia induced secretion (HIS) supports the dominant role of L-VACC subtypes to the regulation of exocytosis at early life. Partial blockade by ω-conotoxin GVIA and ω-agatoxin IVA suggests a transient participation of N and PQ high-VACCs to the regulation of the HIS response at early stages of CC exposure to hypoxia. T-type low-VACC current did not elicit exocytosis triggered by electrical depolarising pulses applied to rat embryo CCs in one study, but largely contributed to the HIS response in neonatal rat adrenal slices in another. In spite of scarce available data, the sequence of events driving the HIS response in CCs at early life could be established as follows: (i) hypoxia blocks one or more K(+) channels; (ii) as a consequence, mild membrane depolarisation occurs; (iii) T-type low-VACCs open at membrane potentials more hyperpolarised than those required to recruit the high-VACCs; (iv) firing of action potentials then occurs; (v) fast-inactivating N and PQ high-VACCs transiently open and low-inactivating L high-VACCs remain open along the hypoxia stimulus; (vi) increase of cytosolic Ca(2+) takes place; and (vii) the exocytotic release of catecholamine occurs in two phases, an explosive initial phase, driven by Ca(2+) entry through L, N and PQ channels, followed by a more sustained catecholamine release at a slower rate driven by L-type channels.

Depressed excitability and ion currents linked to slow exocytotic fusion pore in chromaffin cells of the SOD1(G93A) mouse model of amyotrophic lateral sclerosis.

Altered synaptic transmission with excess glutamate release has been implicated in the loss of motoneurons occurring in amyotrophic lateral sclerosis (ALS). Hyperexcitability or hypoexcitability of motoneurons from mice carrying the ALS mutation SOD1(G93A) (mSOD1) has also been reported. Here we have investigated the excitability, the ion currents, and the kinetics of the exocytotic fusion pore in chromaffin cells from postnatal day 90 to postnatal day 130 mSOD1 mice, when motor deficits are already established. With respect to wild-type (WT), mSOD1 chromaffin cells had a decrease in the following parameters: 95% in spontaneous action potentials, 70% in nicotinic current for acetylcholine (ACh), 35% in Na(+) current, 40% in Ca(2+)-dependent K(+) current, and 53% in voltage-dependent K(+) current. Ca(2+) current was increased by 37%, but the ACh-evoked elevation of cytosolic Ca(2+) was unchanged. Single exocytotic spike events triggered by ACh had the following differences (mSOD1 vs. WT): 36% lower rise rate, 60% higher decay time, 51% higher half-width, 13% lower amplitude, and 61% higher quantal size. The expression of the α3-subtype of nicotinic receptors and proteins of the exocytotic machinery was unchanged in the brain and adrenal medulla of mSOD1, with respect to WT mice. A slower fusion pore opening, expansion, and closure are likely linked to the pronounced reduction in cell excitability and in the ion currents driving action potentials in mSOD1, compared with WT chromaffin cells.

Desarrollo de un modelo experimental de ligadura portal asociada a transección parenquimatosa (ALPPS) en ratas / Development of an experimental model of portal vein ligation associated with parenchymal transection (ALPPS) in rats

ANTECEDENTES: La insuficiencia hepática postresección es una de las principales causas de muerte en el postoperatorio de una hepatectomía mayor. La técnica ALPPS aparece como una estrategia prometedora para evitarla, pero no existen estudios experimentales al respecto. El objetivo del trabajo es desarrollar un modelo experimental de ALPPS en ratas. MÉTODO: Se desarrolló un modelo experimental de ALPPS en 30 ratas Sprague Dawley. Se realizó la ligadura de la rama portal izquierda del lóbulo medio (LM), con lo cual se demarca el sector izquierdo (SILM) y derecho (SDLM); posteriormente se realizó la transección parenquimatosa por la línea isquémica. Se evaluaron el peso del animal, el volumen y peso del LM y de ambos. Sacrificio a los 3, 7 y 14 días (10 por grupo). RESULTADOS: No se presentaron complicaciones hemorrágicas ni ascitis en el postoperatorio. El incremento del volumen del LM fue del 24,1; 86,9 y 120,4% a los 3, 7 y 14 días. El SDLM (no ligado) se incrementó un 34,4; 78,8 y 102,0% a 3, 7 y 14 días. El SILM disminuyó un 42,6; 64,8, y 79,3% en los días 3, 7 y 14. CONCLUSIÓN: La realización del ALPPS fue posible en ratas, logrando los resultados esperados. Futuros estudios son necesarios para compararlo con la técnica de hepatectomía en 2 tiempos

BACKGROUND: Liver failure migth be a cause of death after major hepatectomies. The ALPPS technique appears to be a promising strategy to avoid it, however no experimental studies supporting this procedure have been previously described. The aim was to develop an experimental model of ALPPS in rats. Method. Experimental. A total of 30 Sprague Dawley rats were used. To develop the ALPPS procedure, ligation of the left portal branch of the middle lobe (LM) was performed. This demarcates the left side (SILM) from the right side (SDLM); parenchyma transection was performed following the demarcated line. The animal's weight, volume and weight of both LM were analyzed. Sacrifice at 3, 7 and 14 days after the procedure (10 per group) was performed. RESULTS: No bleeding or ascites were observed during the postoperative period. The LM increased by 24.1, 86.9 and 120.4% at 3, 7 and 14 days. The SDLM increased by 34.4, 78.8 and 102.0% at 3, 7 and 14 days. The SILM decreased 42.6, 64.8, and 79.3% at day 3, 7 and 14 days respectively. CONCLUSION: The ALPPS procedure can be performed in rats, achieving the expected results. Comparison studies to 2 staged hepatectomy will be necessary

Recent patents on calcium channel blockers: emphasis on CNS diseases.

INTRODUCTION: Altered homeostasis of cell calcium movement is a central stage in multiple diseases of CNS. This explains the great therapeutic interest in blockers for the various subtypes of voltage-activated calcium channels (VACCs) expressed in neurons. Mitigation of Ca(2+) entry excess elicited by those blockers may restore the altered synaptic transmission, synaptic plasticity and gene expression to normal parameters, ending the enhanced neuronal vulnerability. AREAS COVERED: This review summarize 23 patents on ligands for L-, N- or T-type channels, claimed to have potential therapeutic interest in epilepsy, pain, migraine and neurodegenerative diseases. EXPERT OPINION: Collections of compounds are generally screened in cell lines expressing a given subtype of VACCs. IC50 to block such channels are often, but not always, provided. In few instances, compounds exhibiting the highest potency in in vitro experiments are also tested in animal models of pain, behavior, epilepsy or Alzheimer's disease. Attempts to develop selectivity for a given VACC subtype with non-peptidic organic ligands have so far failed. Due to their wide tissue expression, such selectivity is crucial for minimizing possible side effects. However, the few data reported by patents does not allow prediction of selectivity of the new compounds in many cases.

Development of an experimental model of portal vein ligation associated with parenchymal transection (ALPPS) in rats.

BACKGROUND: Liver failure might be a cause of death after major hepatectomies. The ALPPS technique appears to be a promising strategy to avoid it, however no experimental studies supporting this procedure have been previously described. The aim was to develop an experimental model of ALPPS in rats. METHOD: Experimental. A total of 30 Sprague Dawley rats were used. To develop the ALPPS procedure, ligation of the left portal branch of the middle lobe (LM) was performed. This demarcates the left side (SILM) from the right side (SDLM); parenchyma transection was performed following the demarcated line. The animal's weight, volume and weight of both LM were analyzed. Sacrifice at 3, 7 and 14 days after the procedure (10 per group) was performed. RESULTS: No bleeding or ascites were observed during the postoperative period. The LM increased by 24.1, 86.9 and 120.4% at 3, 7 and 14 days. The SDLM increased by 34.4, 78.8 and 102.0% at 3, 7 and 14 days. The SILM decreased 42.6, 64.8, and 79.3% at day 3, 7 and 14 days respectively. CONCLUSION: The ALPPS procedure can be performed in rats, achieving the expected results. Comparison studies to 2 staged hepatectomy will be necessary.

Hypoxia-elicited catecholamine release is controlled by L-type as well as N/PQ types of calcium channels in rat embryo chromaffin cells.

At early life, the adrenal chromaffin cells respond with a catecholamine surge under hypoxic conditions. This response depends on Ca(2+) entry through voltage-activated calcium channels (VACCs). We have investigated here three unresolved questions that concern this response in rat embryo chromaffin cells (ECCs): 1) the relative contribution of L (α1D, Cav1.3), N (α1B, Cav2.2), and PQ (α1A, Cav2.1) to the whole cell Ca(2+) current (ICa); 2) the relative contribution of L and N/PQ channels to the cytosolic Ca(2+) elevations triggered by hypoxia (Δ[Ca(2+)]c); and 3) the role of L and non-L high-VACCs in the regulation of the catecholamine surge occurring during prolonged (1 min) hypoxia exposure of ECCs. Nimodipine halved peak ICa and blocked 60% the total Ca(2+) entry during a 50-ms depolarizing pulse to 0 mV (QCa). Combined ω-agatoxin IVA plus ω-conotoxin GVIA (Aga/GVIA) blocked 30% of both ICa peak and QCa. This relative proportion of L- and non-L VACCs was corroborated by Western blot that indicated 55, 23, and 25% relative expression of L, N, and PQ VACCs. Exposure of ECCs to hypoxia elicited a mild but sustained Δ[Ca(2+)]c; the area of Δ[Ca(2+)]c was blocked 50% by nifedipine and 10% by Aga/GVIA. Exposure of ECCs to 1-min hypoxia elicited an initial transient burst of amperometric secretory spikes followed by scattered spikes along the time of cell exposure to hypoxia. This bulk response was blocked 85% by nimodipine and 35% by Aga/GVIA. Histograms on secretory spike frequency vs. time indicated a faster initial inactivation when Ca(2+) entry took place through N/PQ channels; more sustained secretion but at a lower rate was associated to Ca(2+) entry through L channels. The results suggest that the HIS response may initially be controlled by L and P/Q channels, but later on, N/PQ channels inactivate and the delayed HIS response is maintained at lower rate by slow-inactivating L channels.

Murine muscle engineered from dermal precursors: an in vitro model for skeletal muscle generation, degeneration, and fatty infiltration.

Skeletal muscle can be engineered by converting dermal precursors into muscle progenitors and differentiated myocytes. However, the efficiency of muscle development remains relatively low and it is currently unclear if this is due to poor characterization of the myogenic precursors, the protocols used for cell differentiation, or a combination of both. In this study, we characterized myogenic precursors present in murine dermospheres, and evaluated mature myotubes grown in a novel three-dimensional culture system. After 5-7 days of differentiation, we observed isolated, twitching myotubes followed by spontaneous contractions of the entire tissue-engineered muscle construct on an extracellular matrix (ECM). In vitro engineered myofibers expressed canonical muscle markers and exhibited a skeletal (not cardiac) muscle ultrastructure, with numerous striations and the presence of aligned, enlarged mitochondria, intertwined with sarcoplasmic reticula (SR). Engineered myofibers exhibited Na(+)- and Ca(2+)-dependent inward currents upon acetylcholine (ACh) stimulation and tetrodotoxin-sensitive spontaneous action potentials. Moreover, ACh, nicotine, and caffeine elicited cytosolic Ca(2+) transients; fiber contractions coupled to these Ca(2+) transients suggest that Ca(2+) entry is activating calcium-induced calcium release from the SR. Blockade by d-tubocurarine of ACh-elicited inward currents and Ca(2+) transients suggests nicotinic receptor involvement. Interestingly, after 1 month, engineered muscle constructs showed progressive degradation of the myofibers concomitant with fatty infiltration, paralleling the natural course of muscular degeneration. We conclude that mature myofibers may be differentiated on the ECM from myogenic precursor cells present in murine dermospheres, in an in vitro system that mimics some characteristics found in aging and muscular degeneration.