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Hydrogen cyanide (HCN) is considered a fundamental molecule in prebiotic chemistry experiments due to the fact that it could have an important role as raw material to form more complex molecules, as well as it could be an intermediate molecule in chemical reactions. However, the primitive scenarios in which this molecule might be available have been widely discussed. Hydrothermal systems have been considered as abiotic reactors and ideal niches for chemical evolution. Nevertheless, several experiments have shown that high temperatures and pressures could be adverse to the stability of organic molecules. Thus, it is necessary to carry out systematic experiments to study the synthesis, stability and fate of organic molecules in hydrothermal scenarios. In this work, we performed experiments focused on the stability and fate of HCN under a simple hydrothermal system scenario: the thermolysis of HCN at 100°C, at acidic and basic pH and in the presence of Mg-montmorillonite. Furthermore, we analysed the products from HCN thermolysis and highlighted the role of these chemical species as prebiotic molecules under a hydrothermal scenario.
The objective of this study was to identify attitudes towards the scientific search for extraterrestrial life among students from public and private universities in Peru. This research was inspired by similar studies, realized in Sweden, which used the same instrument adapting it to our reality. The process consisted of a survey of the Peruvian student population by targeting it in different regions of Peru. The sample consisted of 1237 students from different academic areas. The findings show that 92% of the students believe in the existence of life outside our planet, with differences between the subgroups surveyed.
The addition of natural progesterone with a continuous daily release rate to inert intrauterine devices has resulted in a lower pregnancy rate and a reduced frequency of bleeding and expulsions. Light microscopy studies on these endometria have shown a suppressed or inactive pattern in addition to inflammatory infiltrate as well as a diffuse predecidual reaction with degenerative changes in most cases. The aim of the present study is to characterize at ultrastructural level the possible modifications seen in cell organelles in both epithelium and stroma resulting from a continuous release rate of progesterone.
Twenty endometrial biopsies were taken; ten at day 10 ± 2 and ten at 20 ± 2 days of the menstrual cycle. Proliferative endometrium disclosed a paucity of cell organelles and it was similar to what has been described for inert devices (2). Secretory endometrium disclosed accumulation of light and dark glycogen in the cytoplasm (Fig. 1).
Impairments in social cognition contribute significantly to disability in schizophrenia patients (SzP). Perception of facial expressions is critical for social cognition. Intact perception requires an individual to visually scan a complex dynamic social scene for transiently moving facial expressions that may be relevant for understanding the scene. The relationship of visual scanning for these facial expressions and social cognition remains unknown.
In 39 SzP and 27 healthy controls (HC), we used eye-tracking to examine the relationship between performance on The Awareness of Social Inference Test (TASIT), which tests social cognition using naturalistic video clips of social situations, and visual scanning, measuring each individual's relative to the mean of HC. We then examined the relationship of visual scanning to the specific visual features (motion, contrast, luminance, faces) within the video clips.
TASIT performance was significantly impaired in SzP for trials involving sarcasm (p < 10−5). Visual scanning was significantly more variable in SzP than HC (p < 10−6), and predicted TASIT performance in HC (p = 0.02) but not SzP (p = 0.91), differing significantly between groups (p = 0.04). During the visual scanning, SzP were less likely to be viewing faces (p = 0.0001) and less likely to saccade to facial motion in peripheral vision (p = 0.008).
SzP show highly significant deficits in the use of visual scanning of naturalistic social scenes to inform social cognition. Alterations in visual scanning patterns may originate from impaired processing of facial motion within peripheral vision. Overall, these results highlight the utility of naturalistic stimuli in the study of social cognition deficits in schizophrenia.
With the spread of coronavirus disease 2019 (COVID-19), strict isolation strategies to limit virus transmission have been applied worldwide. The lockdown has affected and challenged different medical areas. Doctors, nurses, dentists, and other health care workers are concerned about contagion, not only for themselves, but also for their families and colleagues. Furthermore, the oral mucosa has been accepted as a high-risk route of transmission for COVID-19. In many countries, dentists have been forced to stop working during quarantine until further notification. Isolation and its financial impact have produced physical and psychological pressure, depression, social anxiety, and other mental health concerns. This article aims to provide a comprehensive review of the consequences of past epidemics on mental health and to assess possible aspects that might be associated with mental implications in dentists during the COVID-19 pandemic. Finally, some concrete actions to avoid subsequent potential consequences are recommended.
The Paleolithic diet (PaleoDiet) is an allegedly healthy dietary pattern inspired by the consumption of wild foods and animals assumed to be consumed in the Paleolithic era. Despite gaining popularity in the media, different operational definitions of this Paleolithic nutritional intake have been used in research. Our hypothesis is that specific components used to define the PaleoDiet may modulate the association of this diet with several health outcomes. We comprehensively reviewed currently applied PaleoDiet scores and suggested a new score based on the food composition of current PaleoDiet definitions and the theoretical food content of a staple dietary pattern in the Paleolithic age. In a PubMed search up to December 2019, fourteen different PaleoDiet definitions were found. We observed some common components of the PaleoDiet among these definitions although we also found high heterogeneity in the list of specific foods that should be encouraged or banned within the PaleoDiet. Most studies suggest that the PaleoDiet may have beneficial effects in the prevention of cardiometabolic diseases (type 2 diabetes, overweight/obesity, CVD and hyperlipidaemias) but the level of evidence is still weak because of the limited number of studies with a large sample size, hard outcomes instead of surrogate outcomes and long-term follow-up. Finally, we propose a new PaleoDiet score composed of eleven food items, based on a high consumption of fruits, nuts, vegetables, fish, eggs and unprocessed meats (lean meats); and a minimum content of dairy products, grains and cereals, and legumes and practical absence of processed (or ultra-processed) foods or culinary ingredients.
Quantum Dots (QDs) like Cadmium Sulphide have exciting applications, consequent to their size-dependent optical properties. This compound is used as a pigment in papers, paint, and it can also be found in solar cells. Due to the high use of nanoparticles in society, there is a significant concern in the scientific community about the potential toxicity of these nanomaterials in aquatic environments. According to this main problem, we have a theoretical assumption that Cadmium Sulphide (CdS) particles at nanoscale are more toxic than those in macroscale (bulk), and a higher concentration means higher toxicity. To verify its toxicity in the aquatic environment, first, we need to make sure the nanoparticles are soluble in water. Based in the mentioned before, the objectives of this research were: (i) synthesize Cadmium Sulphide QDs in aqueous phase in presence of biocompatible molecules like L-Glutathione and N-Acetyl-L-cysteine, (ii) characterize the quantum dots optically, structurally and morphologically and; (iii) evaluate the toxicity of Cadmium Sulphide in biological systems. CdS, L-Glutathione-covered CdS and N-Acetyl-L-Cysteine-covered CdS evidenced shoulder peaks at 473 nm (2.40 eV), 450 nm (2.62 eV) and, 381 (3.03 eV) nm, respectively. A broad and high emission peak centered at 545 nm was observed for CdS Nps covered with N-acetyl-L cysteine; whereas as QDs without cover and those covered with L-glutathione showed weak peaks in the visible range (470 nm-650 nm). The presence of L-Glutathione or N-Acetyl-L-cysteine on the quantum dots surface was verified by Infrared Spectroscopy. Energy Dispersive X-Ray Spectroscopy (EDX) assays evidenced the chemical composition of produced nanostructures having 57.91% of S and 42.09% of Cd. The morphology and the size were carried out by High-Resolution Transmission Electron Microscopy (HR-TEM). In this way, nanoparticles were spherical and with a size of ~3 nm. Toxicity results evidence that nanoparticles covered with N-Acetyl-L-Cysteine had a negative interaction in marine organisms at concentrations higher than 700 ppm, after 24 or 48 hours of contact. Also, CdS bulk showed absence of toxicity to marine crustaceans.
Green manures are a promising alternative for achieving the sustainable production of maize in the face of low soil fertility and increasingly long canicule periods, particularly in rainfed systems associated with the reproduction of local agrobiodiversity. However, it is necessary to investigate what are the advantages and disadvantages associated with different species of native and exotic pulse, as well as their overall contribution to the sustainable production of maize landraces. In order to do so, we followed the MESMIS method to assess five species of pulse (three native and two exotic) grown with maize in two plots with different soil conditions. This was done in the seasons of 2017 and 2018 the municipality of Villa de Zaachila, Oaxaca, a site with remarkable biological, agricultural and cultural diversity. A fully randomized complete block design was implemented with 11 treatments and three repetitions in the two plots. The output variables of the experiment were: land equivalence ratio, interspecific aggressiveness, content of soil organic matter, decomposition rate, plant survival rate and plant dry biomass. We also evaluated quantitative or qualitative indicators of cost, adaptability and contribution to food security. For all the possible maize-pulse combinations, except for one, polyculture outperformed maize and pulse monocultures. Exotic pulses (Crotalaria junscens spp. and Dolicho lablab) had a better performance in biomass, reincorporation of organic matter and possible nitrogen fixation, as well as greater resistance to drought in the second cycle. The native pulses (Phaseolus vulgaris and Phaseolus coccineus), however, had a greater acceptance and economic output and are important for the food security in our study site. Our results provide quantitative and qualitative elements to design combined schemes of green manures associated with maize that would help tackle current challenges regarding maize productivity, food security and response to climate change.
Amnestic mild cognitive impairment (aMCI) is characterized by delayed P300 latency and reduced grey matter (GM) volume, respectively. The relationship between the features in aMCI is unclear. This study was to investigate the relationship between the altered P300 latency and the GM volume in aMCI.
Thirty-four aMCI and 34 well-matched normal controls (NC) were studied using electroencephalogram during a visual oddball task and scanned with MRI. Both tests were finished in the same day.
As compared with the NC group, the aMCI group exhibited delayed P300 latency in parietal cortex and reduced GM volumes in bilateral temporal pole and left hippocampus/parahippocampal gyrus. A remarkable negative correlation was found between delayed P300 latency and reduced left hippocampal volume only in the aMCI group. Interestingly, the mediating analysis found P300 latency significantly mediated the association between right supramarginal gyrus volume and information processing speed indicated by Stroop Color and Word Test A scores.
The association between delayed P300 latency and reduced left hippocampal volume in aMCI subjects suggests that reduced left hippocampal volume may be the potential structural basis of delayed P300 latency.
The eating disorders are a group of complex psychiatric disorders, severe and frequent medical complications.
symptoms occur along a continuum between the extremes of anorexia and bulimia nervosa. so, we found that more than half of patients develop anorexic and bulimic symptoms that many bulimic patients have a history of anorexia.
We analyzed sociodemographic and clinical variables of a sample of patients attending our clinic within the study period from January to September 2009.
We performed a retrospective descriptive study with data collected from the medical records of 42 patients treated in our mental health center within the study period, who met diagnostic criteria for eating disorders.
Regarding the demographics variables, most of the sample are women (96%), average age 23.5 years, single marital status (54.8%), from middle class (74.1%).
in relation to family history, 53.8% in any family member with pathologies, where mothers have the highest percentage. in personal ancedentes, we found that 35% had childhood obesity and anorexia in 14% of children.
the average age of disease onset was 15.6 years. 66.8% of the sample had had bulimic behavior and the majority (92%) compensatory behaviors.
The eating disorders are a group of chronic and severe. data analysis of our sample showed a profile similar to those provided by epidemiological studies: most women, single, between 10 and 25 years, middle class. Have symptoms frequently comorbid anxiety and depression.
Functional magnetic resonance imaging (fMRI) is a neuroimaging technique increasingly used for both patient care and clinical research. This techniche provides a space-time high-resolution able to detect small changes in regional brain activation.Ojbectives: the aim of this study was to compare patterns of regional brain activation in patients with eating disorders (ED) and healthy volunteers during emotional stimulation.
Materials and methods
A group of 13 young female ED outpatients was selected using DSM-IV criteria and 13 young healthy female volunteers with no significant differences in sociodemographic or environmental data. fMRI was used to examine the neural responses after visual stimulation with neutral and fearful images, taken from the IAPS (International Affective Picture System) and selected a region of interest (ROI) aproach to examine the function of the amygdala in emotional processing.Data processing and higher level analysis were carried out using FSL (fMRI's Software Library).
ED patients showed significantly greater rigth amygdala activation to the fearful images versus neutral images than healthy control subjects (p < 0.02)
A higher right amygdala response to processing of fearful stimuli was observed in ED patients compared to healthy volunteers. This emotional dysregulation in the affective response to unpleasant stimuli would correlate with a maladaptative response and therefore justify disruptive behaviours in this patients.
Mixed Bipolar patients are those who have co-existing depressive symptoms during mania. These patients are supposed to have a worse evolution.
The objective of this study was to compare the long-term outcomes of patients who had at least one mixed episode with those who experienced only pure manic episodes.
169 outpatients diagnosed of Bipolar I disorder and treated at least during two years were included. 120 patients (71%) complited the follow-up over 10 years. Baseline demographic and clinical variables were included.
The patients with mixed episodes (37%) had a significantly younger mean age at onset comparing with those with manic episodes (25.3 years vs. 30.8 years; p=0.025) they also had more previous mood- incongruent psychotic symptoms χ2= 6.77, p=0.034), more number of hospitalizations (OR= 1.36, 95% CI = 1.14; -1.63; p< 0.001), and more number of episodes (OR= 1.21, 95% CI = 1.10-1.31; p< 0.001). There were no significant differences relating to depressive episodes, alcohol use, drug abuse, suicidal behaviour and suicide attempts.
Age at onset differed significantly between the mixed episode and pure mania groups, with mixed episode patients having a younger age of onset. This is interesting as one of the major results of the study we have found that age at onset mediates some of the factors classically related to outcome in mixed episodes like alcohol abuse and suicide attempts. However, independently of age at onset, these patients represent a especially severe type of bipolar disorder.
Alcoholism is a very common psychiatric problem, with a high morbidity and mortality. Psychiatric diagnoses that most often are associated with alcohol-related disorders include substance abuse, antisocial personality trasrtorno, affective disorders, anxiety and sleep disorders.
Our goal is to estimate the prevalence of anxiety and depressive symptoms in a population of patients in our mental health center.
To analyze data from a sample of 35 patients treated in mental health centers that meet diagnostic criteria for alcohol dependence according to DSM IV-TR. the study enrollment period was 6 months from January to June 2009. study design is observational, descriptive and transversal. The information was collected by clinical interview.
Comparison with normativesamples reflects that the alcoholics of the sample present more psychopathological symptoms than the normal populatio, but less than the psychiatric population. Furthermore, the severity of the alcoholism is related with the biggest presence and intensity of comorbidity.
The prevalence of depressive symptoms was 75% and anxious symptoms 65%, with variations in distribution by gender.
The prevalence of anxiety and depression measurement in the population to study is greater than in general population. there is needed further research that allow extending the results obteined in this present study.
In Spain, consumption of psychotropic drugs is high and benzodiazepines represent 74% of the total. His prescription in primary care is very common and their use continues to grow. They are safe and effective drugs, but patients with prolonged use are elaborating the most adverse effects, particularly the dependency.
Descriptive ans cross-sectional.
Primary Health Care.
We seleted 202 patients treated with benzodiazepines, consecutive sample, belonging to the health center Los Barrio who were seen in consultation during 2009.
We conducted through a questionnaire that cointained the treatment and demographic characteristics.
We detect a frequency of use of benzodiazepines 9% (95% CI 4,7-12,1%). The profile of the consumer responds to middle-aged woman, with primary and housewives. Somatic diseases were associated in 72.6% (CI 67,2-77,5%) and had mental pathology at 59.7% (CI 53,9-65,3%). 35% (95% 29,6-40,6%) of prescribed benzodiazepines were clorazape dipotassium. Consumption was constant for over a year. The prescription from primary care represents 81% (95% 76,3-85,4%) and in 65% (CI 59,3-70,3%) is associated with other psychoactive drug.
In our area, highlights the prescription of benzodiazepines from primary care on demand and consumption during prolonged time. Interventions should be conducted on the prescription of benzodiazepines in medical and other interventions for patient support.
The aim of the current study is to analised our clinical experience with pregabalin, evaluate his efficacy and safety in the treatment of generalised anxiety disorder in elderly people.
And safety in the treatment of generalised anxiety disorder in elderly people.
The patients sample was selected of 3 psychogeriatric centers, considering patients 65 years and older with a clinical diagnosis of generalised anxiety disorder with or without psychiaric comorbidity.
The treatment with pregabalin has improved both somatic and mental symptoms of generalised anxiety disorder in the 15 patients analised.
The mean age was 71 years (women 68%). Significant improvement has been observed in the control of psychic and somatic anxiety symptoms in 10 of the 15 patients. In 3 patients the control of the symptoms was partial.
The tolerability of the product has been good in medium doses of 250 mg/day. The most frequently adverse events were somnolence and dizzeness. Discontinuations due to adverse events were in 2 patients
Pregabalin is a novel compound, a structural analogue of gamma-aminobutyric acid (GABA), one of the key inhibitory neurotrnsmitters in the brain. Its mode of action is believed to be mediated by alpha-2-delta-1 subunit protein of voltage-gated calcium channels to bring about its anxiolytic, anticonvulsant and antinociceptive effects.
Pregabalin has been shown to be safe, well tolerated and effective in the treatment of generalised anxiety disorder in patients 65 years old and older.
In Andalucia (Spain), exist a high prescription of antidepressants, joined to an elevated variability in the choice of it.
To describe associated variables with the prescription of antidepressants in Andalucia. To determinate percentage of depresive disorder in antidepressants users.
Primary Health Care, with Health Centers of Andalusian Community participating.
Subjects od the study
Patients older than 18 years old, users of antidepressants. The inclusion in the study will require informed consent by the patient.
Variables to measure
Sociodemographics; Familiars and Personals precedents of mental disorders; number and duration of episodes in which it has taken antidepressants; Hamilton anxiety-depression index; Beck‘s depression index; Diagnosis of depressive disorder or another with need of antidepressant treatment; Comorbility ; Origin of the presciption. Variables in relation with the prescriptor will be mesurement.
It is calculated by accepting a signification level of 95%, and a percentage of depresive disorder over antidepressants users unknowed (p = q = 50%). A sample size of 770 patients is estimated, including losses.
Determinations will be carried out through descriptive statistics; frequency distribution, dispersion and central tendency measurements. A measurement of possible associations between variables through contrast of hypothesis test will also be calculated. So, Pearson's chi-square test for qualitatives variables and analysis of variance (ANOVA) for quantitatives. The study will be finished studig association between potentials variables existing in antidepressants users and depression diagnosis through model of binary logistic regression.
Sexuality is a crucial area of human life. A proper examination to assess and detect problems in this field, it seems imperative to intervene when transsexual patients. Therefore accurately known, the sexual practices of these patients, allows us to work directly on possible alterations in the functioning of sexual life during the therapeutic process.
Describe patterns of sexual behavior in patients diagnosed with transsexualism
Gender and Identity Disorder Unit (GIDU)
Selected by consecutive sampling, 200 transsexuals treated at GIDU Malaga, aged between 20 and 40 years and who agreed to participate in the study. Comprising 142 transgender male-to-woman (MtW) and 58 women-to-man (WtM).
Was conducted through a heterocompleted questionnaire that included questions about sexuality, personality traits and demographic characteristics. These were filled in the consultation and were anonymous.
11.6% of MtW transsexuals have never had sex. 26.8% of the MtW and 29% of WtM are more than 3 months without masturbating. 54.1% of the MtW avoid having sex due to the rejection of his genitals, lack of sexual desire and previous traumatic experience. Transgender respondents had secondary education, stable jobs and they were single.
It is vital that we explore the sex lives of transsexual patients. This information must be integrated in a systematic and rigorous evaluation process. According to the results presented, the hyposexuality would be the most significant feature that describes sexuality for this population.
Schizophrenia is a debilitating and cronic disease for which full recovery is typically not considered to be a realistic treatment endpoint. Symptomatic remission, however, may be an objectively attainable treatment goal.
We wanted to assess remission rates over 52 weeks in patients with schizophrenia treated with ziprasidone
Remission rates were calculated using data from a 52 week study in which patients diagnosed with acute schizophrenia were stabilized with ziprasidone (n=30, dose 120-140mg/day) For this analysis, remission was operationalized according to the consensus-based symptomatic remission criteria established by the Remission in Schizophrenia Working Group. Accordingly, patients were required to achievescores Syndrome Scale (PANSS) items (delusions, unusual thought content, hallucinatory behavior, conceptual disorganization, mannerisms/posturing, blunted affect, social withdrawal, lack of spontaneity) and to maintainthe item score threshold for at least 6 consecutive months.
Thirty-seven percent of ziprasidone treated patients satisfied the criteria for symptomatic remission within the 52-week trial period. Approximately 7% of patientslost their remission status prior to the end of thetrial, with mean time in remission of 6.5 months. Forty-six percent of patients never met the PANSS item threshold. During the 52-week study, few patients discontinued due to adverse events other than worsening of symptoms(7%) or received concomitant medication for EPS (18%)
Nearly one third of the patients treated with ziprasidone achieved remission status within 6 months. Most patients who achieved remission remained in remission for more than 9 months until trial termination. Overall CGI-Is of these patients were significantly better than for patients without remission.
We analyzed the association of age at onset of psychosis(AOP) with having a history of cannabis use in patients with a first episode of non-affective psychosis(FENAP) and investigated the impact on the AOP of exposure to cannabis in adolescence, compared with young adulthood, and of the additional exposure to cocaine.
We recruited 112 consecutive patients with a FENAP. CIDI was used to assess drug use and to define the age at onset of heaviest use(AOHU) of a drug, as the age when drug was used the most for each patient. The effect of cannabis and cocaine AOHU on AOP was explored through Kruskal-Wallis and Mann-Whitney tests, and logistic regression. Sex-adjusted cumulative hazard curves and Cox regression models were used to compare the AOP of patients with and without a history of cannabis use, or associated cocaine use.
AOP was significantly associated with the use of cannabis, independently of sex, use of cocaine, tobacco smoking or excessive alcohol consumption. There was a dose-response relationship between cannabis AOHU and AOP: the earlier the AOHU the earlier the AOP. Hazard curves showed that patients with a history of cannabis use had a higher hazard of having a first episode psychosis than the rest of the patients (sex-adjusted log rank χ2=23.43,df=1, p< 0.001). Their respective median AOP (25th, 75th percentiles) were 23.5 (21,28) and 33.5 years (27,45) (for log-transformed AOP, t=5.6, df=110, p< 0.001).
Our results are in favor of a catalytic role for cannabis use in onset of psychosis.