Hypertrophic cardiomyopathy induces changes in the tryptophan-5-hydroxylase, serotonin transporter and serotonergic receptors expressions

INTRODUCTION

Cardiomyocytes have a biochemical machinery with the capacity to synthesize, utilize and reuptake serotonin.

OBJECTIVE

To determine whether hypertrophic cardiomyopathy (HCM) induces changes in the expression of tryptophan-5-hydroxylase (TPH) 1 and 2, serotonin transporter (SERT) and serotonergic receptors (SR).

METHODS

Cross-sectional study of five tissue blocks from hearts with HCM and five controls. Five sections of the left ventricular free wall (LVFW) and interventricular septum (IVS) were obtained from each block to determine the expression of TPH1 and TPH2, SERT and SRs by immunofluorescence with specific antibodies. Immunofluorescence was evaluated by WELCH t-test, with a level of significance of p < 0.05.

RESULTS

LVFW and IVS of hearts with HCM showed an increase in the expression of TPH1 and TPH 2 and 5-HT_2A and 5-HT_2B receptors in comparison with controls (p < 0.01). The 5-HT₄ receptor and SERT showed an increase in the IVS of hearts with HCM (p < 0.01).

CONCLUSIONS

This study demonstrated an increased expression of TPH, SERT and SRs in cardiomyocytes from hearts with HCM in comparison with controls, which could be involved in the pathophysiology of HCM in humans.

Who judges medical practice?

Lawsuits due to patient perception of inappropriate medical actions are a growing reality in medical practice, which entails widespread concern in the medical community. Lawsuits often entail additional circumstances beyond the primary concern of preventing or sanctioning acts of medical negligence. CETREMI proposes various recommendations aimed at legal and medical professionals to improve this circumstance and avoid harming the doctor-patient relationship.

Aplicaciones terapéuticas por acción de los cannabinoides

The interest on cannabinoids became evident between the 1940 and 1950 decades. Although the active substance of the plant was not known, a series of compounds with cannabinomimetic activity were synthesized, which were investigated in animals and clinically. The most widely tested was Δ6a, 10a-THC hexyl. Δ6a, 10a-THC dimethylheptyl (DMHP) antiepileptic effects were studied in several children, with positive results being obtained in some cases. DMHP differs from sinhexyl in that its side chain is DMHP instead of n-hexyl. The first cannabinoid isolated from Cannabis sativa was cannabinol, although its structure was correctly characterized several years later. Cannabidiol was isolated some years later and was subsequently characterized by Mechoulam and Shvo. In 2013, the National Academy of Medicine and the Faculty of Medicine of the National Autonomous University of Mexico, through the Seminar of Studies on Entirety, decided to carry out a systematic review on a subject that is both complex and controversial: the relationship between marijuana and health. In recent years, studies have been conducted with cannabis in several diseases: controlled clinical trials on spasticity in multiple sclerosis and spinal cord injury, chronic, essentially neuropathic, pain, movement disorders (Gilles de Latourette, dystonia, levodopa dyskinesia), asthma and glaucoma, as well as non-controlled clinical trials on Alzheimer's disease, neuroprotection, intractable hiccups, epilepsy, alcohol and opioid dependence and inflammatory processes.

[Posición de la Academia Nacional de Medicina de México con el fin de regular el uso de células troncales y de embriones humanos para fines terapéuticos o de investigación]

In recent years, the use of stem cells for therapeutic purposes has received attention from research groups. In Mexico, the Mexican Official Standard 260-SSAI-2015 regarding the use of stem and progenitor cells for therapeutic and research purposes is in the process of authorization. Even when this has not been approved, an increasing number of establishments are offering medical services involving the use of stem cells for therapeutic purposes without official regulatory authorization. The Mexican Academy of Medicine of Mexico makes its position public in favor of regulating the use of stem cells and embryos for therapeutic and research purposes.

[Posición de la Academia Nacional de Medicina de México con relación con el decreto presidencial por el que se reforman y adicionan diversas disposiciones de la Ley General de Salud, en específico aquella donde faculta a la Secretaría de Salud para diseñar y ejecutar políticas públicas que regulen el uso medicinal y científico de los derivados farmacológicos de la Cannabis sativa indica americana o marihuana, entre los que se encuentra el tetrahidrocannabinol, sus isómeros y variantes estereoquímicas, así como para normar la investigación y producción nacional de los mismos]

As a consequence of the Presidential Decree that reforms and additions the General Statute of Health with regard to medicinal and scientific use of tetrahydrocannabinol, its isomers and stereochemical variants, the National Academy of Medicine of Mexico declares its position in favor of regulating investigation and national production thereof.

[Tratamientos estéticos. Posición de la Academia Nacional de Medicina de México]

In Mexico there is a proliferation of "centers for aesthetic medicine" that offer different treatments with laser beam, mesotherapy and hyaluronic acid and botulinum toxin injections. In numerous centers of this type, offered and performed by medical personnel that are neither trained or certified to ensure the quality of services. The National Academy of Medicine of Mexico and the National Normative Council for Medical Specialties (CONACEM) communicate their posture on this matter.

[Postura de la Academia Nacional de Medicina de México en relación con las decisiones sobre el final de la vida]

There are decisions at the end of life that currently are relevant as humanistic values. Respect for human life and dignity are part of human rights. The National Academy of Medicine of Mexico declares its posture about end-of-life decisions that include treatment refusal, limitation of the therapeutic effort, advance directives and palliative sedation, among others, with the purpose to favor a peaceful death.

[National Academy of Medicine, one hundred and fifty-four academic year]

El incalculable valor que atesora la Academia Nacional de Medicina, su enorme influencia y repercusión sobre la toma de decisiones médico-científico-epidemiológicas, radica única y exclusivamente en el dominio del conocimiento, la mente científica y el talento de todos y cada uno de sus miembros, desde su fundación en 1864 hasta nuestros días.

Effect of late-onset fetal growth restriction on organization of behavioral state in infants

BACKGROUND

The aim of this study was to analyze whether late-onset fetal growth restriction (FGR) alters regulatory capability in infants, and whether this can be detected using both the neonatal behavior assessment scale (NBAS) and brainstem auditory-evoked potentials (BAEP).

METHODS

The diagnosis of FGR was made on Doppler examination in the third trimester of pregnancy. NBAS and BAEP measurement were performed at 1 month of corrected postnatal age.

RESULTS

The group with late-onset FGR was integrated with 17 infants and the control group consisted of 14 subjects. The NBAS range of state score, which reflects organization of behavioral state, was low in infants with late-onset FGR. No differences were found in BAEP between groups. No association between NBAS and BAEP was detected.

CONCLUSION

Late-onset FGR has a deleterious effect on NBAS range of state, but possibly does not alter BAEP response. It is proposed that regulatory capabilities in the neonatal period play a primary role in subtle cognitive difficulties in infants with late-onset FGR in the long term.

[Survey about responsiveness of third-level hospitals to a medical disaster: after the pandemic influenza in Mexico]

BACKGROUND

The recent pandemic influenza AH1N1 virus made it clear that planning for medical disaster response is critical.

OBJECTIVE

To know the responsiveness of a sample of highly specialized hospitals in Mexico to a medical disaster, with the previous pandemic influenza AH1N1 as reference.

METHODS

A survey was conducted among the Medical Directors of a sample of highly specialized hospitals, covering: previous experience with the pandemic influenza, space considerations, material resources, staff, logistics, and current general perspectives. Descriptive statistics were used for analysis.

RESULTS

A 95% response was obtained from the institutions (19 hospitals). Of these, 47.4% considered that the medical institution was not ready to respond to pandemic influenza. The median surge capacity for the Intensive Care Unit beds was 30% (range 0 to 32 beds). The least reserve in medication was found in the antivirals (26.3%). Only 47.4% considered having enough intensive care nurses and 57.9% enough respiratory technicians; 42.1% would not have an easy access to resources in an emergency.

CONCLUSIONS

Prevention is key in responsiveness to medical disasters, and therefore the basic steps for planning strategies must be considered.

Beneficial effects of the n-3 long-chain polyunsaturated fatty acids in surgical patients: updating the evidence

The use of n-3 polyunsaturated fatty acids in surgical patients has risen by the fact that this may attenuate systemic and acute inflammatory responses secondary to surgical trauma through modulation of inflammatory mediators and cell membrane interactions. Moreover, the inclusion of n-3 fatty acids in clinical trials as part of the therapy in patients, who expect to undergo a surgical stress, suggests benefits on clinical progress. Therefore, the objective of this article is to review data from n-3 polyunsaturated fatty acid effects on biochemical parameters and on reduced length of hospitalization, number of infections, and mortality as main clinical outcomes in human surgical patients.

[Signal transduction, pillar of the neurobiological integration of memory. An alternative view to the cholinergic hypothesis]

Neurophysiological, biochemical and molecular processes described in the integration of memory are closely related with neurotransmitters such as glutamate and serotonin (SHT) and with the function of calcium and potassium ion channels more than with cholinergic activity. Infact, glutamate and 5-HT receptors are closely related with Long-Term potentiation (L TP) processes, the mechanism by which memory is preserved throughout time. That is, the activation of the 5-HTI receptor triggers a transduction signal that after influencing nuclear cell activity, provokes several presynaptic changes, which leads to the displacement of magnesium from the postsynaptic area depolarizing the neuron and leading to the activation of N-methyl-D-aspartate receptors (NMDA). As a whole, this process contributes to the support and perpetuation of LTP, which consists of the following processes: LTPI that depends on protein kinase activity; LTP2 linked to translation of genes; and LTP3 closely related to genes transcription. On the opposite side but in perfect balance, we find the mechanism of Long-Term depression (LTD), which is triggered instead when the Ca+ +flow decreases in the presynaptic neuron activating the inhibitor-1 enzyme that promotes the dephosphorylation of a calmodulin-dependent protein kinasell and as a result, the inhibition of autophosphorylation and consequently of LTP too. Despite the widespread dissemination of the cholinergic hypothesis in Alzheimer's disease, memory build up rather than involving acetylcholine essentially depends on the participation of other neurotransmitters such as 5-HT and glutamate, which have not been adequately considered in the treatment of this disease. However, beyond neurotransmission, it is the cellular mechanism of autophosphorylation of several protein kinases, the process susceptible of being activated or controlled by the action of distinct substances. In such a case, it would be possible to exert some influence on gene expression improving perhaps, some of the physiopathological deficits that characterize memory disruption.

[Calcium, the atom triggering life and cellular function]

Although during the last three decades phosphorylation and dephosphorylation systems have been pointed out as the mechanisms used by living cells to control biological processes, it seems that calcium dynamics is the phenomenon that precedes and controls protein activation by the introduction of phosphate groups into distinct protein structures. The process begins with activation of calcium channels that allows the influx of the ion, which once inside the cell leads to calcium-calmodulin complex, a molecule capable of triggering activation of distinct proteinkinases. Thus, the cell in addition to suffering a change in polarity enhances neuroconduction and release of different substances such as hormones and para-hormones, facilitates intra- and intercellular communication, and exerts determinant influence on phenotypic expression by means of promotion of immediate and mediate response genes. Ionic conformational calcium runs short- and long-term facilitation mechanisms, exerting its influence on control of memory through homosynaptic depression and hetersynaptic facilitation processes; triggers autophosphorylation of several enzymes leading and enhancing cellular activity and participates in signal transduction and decodification. Calcium influx rate activates certain groups of phosphatases capable of inhibiting autophosphorylation processes, only as a negative feedback mechanism. In addition, ionic calcium also participates in the "cross-activate" mechanism of proteinkinases A and G, influencing to production of systemic and central nervous system nitric oxide. On these bases, it is possible to guess that future pharmacologic interventions on calcium fluxes could be of invaluable importance in prevention and control of a number of distinct physiopathologic events.

[Ultrastructural findings during human myocardial preservation with HTK solution]

Although the majority of recent scientific advances developed in the field of myocardial preservation have improved surgery procedures, it seems that during cardiothoracic surgery ischemia-reperfusion continues triggering clinical postoperative problems. This report focused on the changes human capillary endothelial cells and nerve endings suffer after cardiopulmonary bypass. The study involved four patients who received Bretschneider solution for cardioplegia during mitral stenosis surgery. Biopsies of right atrium were taken prior to and after CPB to be analyzed under electron microscopy. Samples taken after CPB showed detachment of myocardial capillary basal membrane, endothelial edema, and widespread nerve-ending destruction. Nevertheless, the shelter provided by the most advanced cardioplegic solutions, myocardial endothelial edema, and nerve-ending destruction cannot be completely prevented. Thus, it is possible to suggest that low interstitial concentration of Na(+), which activates Na(+)/Ca(++) exchanger, and inflow of Ca(++), present during ischemia-reperfusion, may lead to endothelial and neuronal cell damage, triggering cardiac contraction dysfunction. This mechanism would explain at least in part some of the problems patients face during the postoperative state.

For ischemic brain damage, is preclinical evidence of neuroprotection by presynaptic blockade of glutamate release enough?

Some drugs blocking glutamate release produce reduced brain injury in some animal models of cerebral ischemia whereas others lack a clear effect. Meta-analysis is a widely used technique in clinical and epidemiological studies. However, it has never been used in the analysis of preclinical studies. In order to estimate quantitatively the current state of the knowledge concerning the neuroprotective effect of drugs inhibiting glutamate release and to attempt to resolve the apparent controversy in relation to the neuroprotective properties of these drugs, a meta-analysis was performed. It identified a significant difference between drugs blocking glutamate release and controls. Therefore, we hypothesize that inhibition of presynaptic glutamate release could be a major goal in neuroprotection when ischemic brain damage is present and that meta-analysia could be a useful tool for preclinical studies,

Dendritic spine pathology in infants with severe protein-calorie malnutrition

BACKGROUND

Experimental undernutrition in animals, during the critical brain development period, produces retardation of brain growth as well as a number of different morphologic and functional abnormalities in neurons, mainly in the dendritic synaptic apparatus. These alterations are the cause of the poor neurointegrative development that occurs in experimental malnutrition. Severe malnutrition during early postnatal life in humans is known to produce similar neurointegrative disorders as well as mental retardation, but there are very few studies describing the morphology of the dendritic apparatus in infants suffering from this condition.

OBJECTIVE

To study the dendritic spine density and morphology in dendrites from cortical neurons in infants dying from severe malnutrition.

METHODOLOGY

Brain sections from the somestesic, motor, and occipital cortical areas of 13 infants who died of severe malnutrition and 7 eutrophic infants who died of other causes were studied by means of the rapid Golgi method. Apical dendritic spines from neurons of the fifth cortical layer were studied and counted in all sections.

RESULTS

Apical dendrites were significantly shorter in malnourished infants than in the control group (581.54 +/- 54.32 microm in severe malnutrition vs 846.3 microm in normal infants). The number of dendritic spines per dendrite was also significantly diminished (185.3 +/- 36.1 in malnourished vs 374.3 +/- 41.6 in eutrophic infants). There were marked morphologic abnormalities in the dendritic spines of infants dying of severe malnutrition that were classified as dysplastic.

CONCLUSIONS

Short apical dendrites, fewer spines, and dendritic spine abnormalities occur in severe infant malnutrition. These anatomic anomalies might be related to the neuropsychological deficits that occur in these children.