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1.
Int J Biol Macromol ; 222(Pt B): 1688-1699, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-36179871

ABSTRACT

Corn starch dispersions (CSD) were hydrolyzed with citric acid and compared with CSD co-treated with citric acid combined with ultrasonication for 1 to 18 days, which are designated as single modification (CSD-SM) and dual modification (CSD-DM), respectively. The logistic functions monitor the dynamics of the hydrolysis advance (%) of the CSD-SM and CSD-DM as a function of time, where the zones most vulnerable to the single-treatment and/or co-treatment of the corn starch granules (CSG) are the amorphous or disordered regions. The characterization results of CSD-DM suggest that the structural changes caused by dual modification affected the morphology, sequence, and microstructure of the CSG. The heterogeneous changes caused by the dual modification changed the configuration of the CSG, generating a kind of destemming of the amorphous lamellae (depolymerization), an increase in the percentage of relative crystallinity of the CSD-DM and an active rearrangement of the intralamellar chains that promoted the relative amount of double helix for 18 days of double modification. The synergistic effect of the dual modification for CSD by the sequential combination of a chemical treatment followed by a physical one improved the hydrolyzed advance by 12 %, the relative crystallinity by 10 %, and the promotion of double helices by 25 % during 18 days of co-treatment.


Subject(s)
Starch , Zea mays , Starch/chemistry , Hydrolysis , Zea mays/chemistry , Citric Acid/chemistry , Kinetics
2.
Mater Sci Eng C Mater Biol Appl ; 123: 111934, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33812573

ABSTRACT

In the present study, graphite oxide, graphite oxide doped with 0.8 g AgNO3 named GrO-0.5Ag, and graphite oxide doped with 1.25 g AgNO3 named GrO-1.0Ag (silver-doped graphitic materials) were synthesized by the modified Hummers and chemical doping methods. Subsequently, its antimicrobial activity against Bacillus subtilis, Candida albicans, Escherichia coli, and Staphylococcus aureus microorganisms was evaluated by agar well diffusion test with 1 and 2 mg·ml-1 of material concentrations. The silver-doped graphitic materials were characterized by X-Ray Diffraction, Fourier-Transform Infrared, Raman, X-Ray Photoelectron spectroscopies, and Scanning Electron Microscopy. The GrO-0.5Ag material showed a percentage of inhibition effect of 86, 82, 48, and 45% with respect to the positive control for Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Candida albicans microorganisms, respectively. Otherwise, the GrO-1.0Ag material showed a percentage of inhibition effect of 54% with respect to the positive control for Bacillus subtilis and less than 50% for the other microorganisms. The material concentrations showed a slight change in the percentage of inhibition effect for all microorganisms. Graphite oxide functional groups, small crystal size, free silver ions, and silver carbonate formation in silver-doped graphitic materials presented a viable alternative to inhibit bacterial growth.


Subject(s)
Anti-Infective Agents , Graphite , Metal Nanoparticles , Agar , Bacillus subtilis , Candida albicans , Escherichia coli , Oxides/pharmacology , Silver/pharmacology , Staphylococcus aureus
3.
Prog Neurobiol ; 129: 58-78, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25930682

ABSTRACT

Panic attacks (PAs), the core feature of panic disorder, represent a common phenomenon in the general adult population and are associated with a considerable decrease in quality of life and high health care costs. To date, the underlying pathophysiology of PAs is not well understood. A unique feature of PAs is that they represent a rare example of a psychopathological phenomenon that can be reliably modeled in the laboratory in panic disorder patients and healthy volunteers. The most effective techniques to experimentally trigger PAs are those that acutely disturb the acid-base homeostasis in the brain: inhalation of carbon dioxide (CO2), hyperventilation, and lactate infusion. This review particularly focuses on the use of CO2 inhalation in humans and rodents as an experimental model of panic. Besides highlighting the different methodological approaches, the cardio-respiratory and the endocrine responses to CO2 inhalation are summarized. In addition, the relationships between CO2 level, changes in brain pH, the serotonergic system, and adaptive physiological and behavioral responses to CO2 exposure are presented. We aim to present an integrated psychological and neurobiological perspective. Remaining gaps in the literature and future perspectives are discussed.


Subject(s)
Brain/physiopathology , Carbon Dioxide/metabolism , Homeostasis/physiology , Panic Disorder/physiopathology , Serotonin/metabolism , Animals , Humans , Hydrogen-Ion Concentration
4.
Food Chem ; 172: 353-60, 2015 Apr 01.
Article in English | MEDLINE | ID: mdl-25442564

ABSTRACT

Maize starch was lime-cooked at 92 °C with 0.0-0.40% w/w Ca(OH)2. Optical micrographs showed that lime disrupted the integrity of insoluble remnants (ghosts) and increased the degree of syneresis of the gelatinized starch dispersions (GSD). The particle size distribution was monomodal, shifting to smaller sizes and narrower distributions with increasing lime concentration. X-ray patterns and FTIR spectra showed that crystallinity decreased to a minimum at lime concentration of 0.20% w/w. Lime-treated GSD exhibited thixotropic and viscoelastic behaviour. In the linear viscoelastic region the storage modulus was higher than the loss modulus, but a crossover between these moduli occurred in the non-linear viscoelastic region. The viscoelastic properties decreased with increased lime concentration. The electrochemical properties suggested that the amylopectin-rich remnants and the released amylose contained in the continuous matrix was firstly attacked by calcium ions at low lime levels (<0.20% w/w), disrupting the starch gel microstructure.


Subject(s)
Calcium Compounds/chemistry , Oxides/chemistry , Starch/chemistry , Zea mays/chemistry , Chromatography, Gel , Cooking , Elasticity , Particle Size , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction
5.
Mol Psychiatry ; 17(12): 1194-205, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22290124

ABSTRACT

Investigating and understanding gene-environment interaction (G × E) in a neurodevelopmentally and biologically plausible manner is a major challenge for schizophrenia research. Hypoxia during neurodevelopment is one of several environmental factors related to the risk of schizophrenia, and links between schizophrenia candidate genes and hypoxia regulation or vascular expression have been proposed. Given the availability of a wealth of complex genetic information on schizophrenia in the literature without knowledge on the connections to environmental factors, we now systematically collected genes from candidate studies (using SzGene), genome-wide association studies (GWAS) and copy number variation (CNV) analyses, and then applied four criteria to test for a (theoretical) link to ischemia-hypoxia and/or vascular factors. In all, 55% of the schizophrenia candidate genes (n=42 genes) met the criteria for a link to ischemia-hypoxia and/or vascular factors. Genes associated with schizophrenia showed a significant, threefold enrichment among genes that were derived from microarray studies of the ischemia-hypoxia response (IHR) in the brain. Thus, the finding of a considerable match between genes associated with the risk of schizophrenia and IHR and/or vascular factors is reproducible. An additional survey of genes identified by GWAS and CNV analyses suggested novel genes that match the criteria. Findings for interactions between specific variants of genes proposed to be IHR and/or vascular factors with obstetric complications in patients with schizophrenia have been reported in the literature. Therefore, the extended gene set defined here may form a reasonable and evidence-based starting point for hypothesis-based testing of G × E interactions in clinical genetic and translational neuroscience studies.


Subject(s)
Brain/blood supply , Cardiovascular Physiological Phenomena/genetics , Gene-Environment Interaction , Genetic Predisposition to Disease/genetics , Hypoxia-Ischemia, Brain/genetics , Schizophrenia/genetics , DNA Copy Number Variations/genetics , Databases, Genetic , Genome-Wide Association Study/methods , Genome-Wide Association Study/statistics & numerical data , Humans , Models, Neurological
6.
Rev. MVZ Córdoba ; 16(3): 2678-2685, sept.-dic. 2011.
Article in Spanish | LILACS | ID: lil-621976

ABSTRACT

Objetivo. Determinar el efecto de dietas con diferentes proporciones de fuentes proteicas animales y vegetales suplementadas con plancton sobre el crecimiento y sobrevivencia en larvas de Rhamdia quelen. Materiales y métodos. Fueron formuladas dos dietas experimentales, dieta-1 con 70% de proteína de origen vegetal (torta de soya) y dieta-2 con 70% de proteína proveniente de animales (corazón bovino y harina de pescado); se utilizaron cuatro protocolos de alimentación (cinco réplicas por tratamiento): dieta-1 + plancton filtrado en tamiz de 50-200 micras (T1), dieta-2 + plancton filtrado en tamiz de 50-200 micras (T2), dieta-1 (T3), dieta-2 (T4). Las larvas fueron manejadas a una densidad de 20 animales L-1 suministrando alimento hasta aparente saciedad diariamente a las 07:00, 11:00, 16:00 y 21:00 horas; la suplementación con plancton se realizó a las 11:00 y 21:00 horas. Resultados. Entre T1 y T2 no se observaron diferencias estadísticas (p>0.05) en peso final (21.89 ± 15.17mg vs 20.37 ± 10.37mg), longitud total (13.41±2.34mm vs 13.39±1.99 mm), factor de condición (K) (0.80±0.13 vs 0.78±0.13 ) y sobrevivencia (46.6±2.68% vs 36.0±7.41%); las diferencias entre T3 y T4 tampoco fueron significativas (3.35±1.40 mg vs 2.98±1.48 mg; 7.54±0.91mm vs 7.33±0.96mm; 0.75±0.13 vs 0.71±0.12; 33.6±9.07% vs 24.8±6.76%, respectivamente); hubo diferencias significativas (p<0.05) entre los grupos suplementados con plancton y los alimentados solo con ración. Conclusiones. La suplementación con plancton fue más efectiva que el ofrecimiento solo de ración. La inclusión del 62.9% de torta de soya en la formulación (T1), aparentemente no afectó el crecimiento ni la sobrevivencia.


Subject(s)
Animals , Food , Plankton
7.
J Psychopharmacol ; 24(5): 639-47, 2010 May.
Article in English | MEDLINE | ID: mdl-19460873

ABSTRACT

Several methods to experimentally induce panic cause profound acid-base disturbances. Evidence suggests that CO(2) inhalations, lactate infusions and, to a certain extent, voluntary hyperventilation can conceivably lead to a common scenario of brain acidosis in the face of disparate intravascular pH alterations. The importance of this event is reflected in data that support a model in which experimental panic attacks, as proxy to those occurring spontaneously, constitute a response to acute brain acidosis. Given that central CO(2)/H(+) chemoreception is an important drive for ventilation, and many chemosensitive neurons are related to respiration and arousal, this model can explain much of the connection between panic and respiration. We propose that the shared characteristics of CO(2)/H(+) sensing neurons overlap to a point where threatening disturbances in brain pH homeostasis, such as those produced by CO(2) inhalations, elicit a primal emotion that can range from breathlessness to panic.


Subject(s)
Acidosis/physiopathology , Brain/metabolism , Brain/physiopathology , Panic Disorder/etiology , Panic Disorder/physiopathology , Acidosis/metabolism , Acidosis, Lactic/metabolism , Acidosis, Lactic/physiopathology , Acidosis, Respiratory/metabolism , Acidosis, Respiratory/physiopathology , Animals , Brain Chemistry/physiology , Carbon Dioxide/metabolism , Chemoreceptor Cells/physiology , Humans , Hydrogen-Ion Concentration , Panic Disorder/chemically induced , Panic Disorder/metabolism
8.
J Psychopharmacol ; 23(8): 975-8, 2009 Nov.
Article in English | MEDLINE | ID: mdl-18635711

ABSTRACT

Several reports have linked, among other aspects, the role of an opioid system in respiratory physiology with underlying mechanisms of panic attacks. The involvement of the opioid system in experimental panic is to be further probed. This study aimed to determine whether opioid blockade would increase panic-related symptomatology on provocation with 35% CO2 inhaled by healthy volunteers. Participants in a double-blind, randomised crossover design orally received either 50 mg of naltrexone or placebo. Most subjects undertook a double inhalation of 35% CO2 one hour after pre-medication, and a separate group did so after five hours. The reactivity to CO2 and the symptoms elicited by naltrexone alone were measured. Among other findings, naltrexone pre-medication alone elicited significant increments in panic-related symptoms. Responses to CO2 were not significantly different between conditions in either group. These preliminary findings suggest that exposure to opioid blockade alone can potentially elicit symptoms that resemble panic, however, without modifying the response to experimental panic provocation with 35% CO2.


Subject(s)
Carbon Dioxide/toxicity , Naltrexone/pharmacology , Narcotic Antagonists , Panic Disorder/etiology , Adult , Cross-Over Studies , Double-Blind Method , Female , Humans , Male , Receptors, Opioid/physiology
9.
Gac méd espirit ; 5(1)ene.-abr., 2003.
Article in Spanish | CUMED | ID: cum-36030

ABSTRACT

Se realizó un estudio descriptivo transversal en el periodo comprendido de Enero-Diciembre del 2000 en el municipio de Fomento, al encontrar que la tasa de mortalidad por enfermedad Cerebro Vascular se había duplicado con respecto al propósito. Se revisaron todas las Historias Clínicas de los pacientes fallecidos por esta causa, encontrándose que la muerte ocurrió fundamentalmente en la mujer blanca mayor de 65 años, existió relación estrecha con la Hipertensión, el sedentarismo y el tabaquismo. Se apreciaron algunos incumplimientos en el protocolo de diagnóstico y tratamiento de la patología. [AU]


Subject(s)
Humans , Cerebrovascular Disorders/mortality
10.
Acta Psychiatr Scand ; 106(5): 394-7, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12366475

ABSTRACT

OBJECTIVE: To test the possible antipanic effects of acute exercise in healthy volunteers exposed to an inhalation of 35% CO2 challenge. METHOD: Twenty healthy subjects in a randomized separate group design, performed exercise in a bicycle ergometer reaching >6 mm of blood lactate and a control condition of minimal activity in the same fashion with no lactate elevation. Immediately afterwards an inhalation of a vital capacity using a mixture of 35% CO2/65% O2 through a mask was given on both conditions. RESULTS: Subjects under the exercise condition reported less panic symptoms than controls after a CO2 challenge on the diagnostic statistical manual-IV (DSM-IV) Panic Symptom List but no difference on the Visual Analogue Anxiety Scale. CONCLUSION: Subjects under the exertion condition had lactate levels comparable with those of lactate infusions but an inhibitory rather than accumulative effect was seen when combined with a CO2 challenge.


Subject(s)
Carbon Dioxide , Exercise/physiology , Lactates/blood , Panic , Adult , Exercise Test , Female , Humans , Male , Vital Capacity
11.
Child Abuse Negl ; 25(1): 13-31, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11214807

ABSTRACT

OBJECTIVE: The goal of the study was to investigate whether maltreated children differ from nonmaltreated children with regard to their social skills and play behaviors. METHOD: The social skills and free-play behaviors of 30 3- to 5-year-old maltreated and nonmaltreated children were compared. Fifteen children with a range of maltreatment experiences drawn from a hospital-based therapeutic nursery treatment program and 15 demographically similar children drawn from a home-based Head Start program participated in the study. All children were of low socioeconomic status. Children's free-play peer interactions were videotaped during the first 3 months of attendance in either program and analyzed along social and cognitive dimensions. Teachers and therapists rated children's social skills in peer interactions. RESULTS: Maltreated children were found to have significantly poorer skill in initiating interactions with peers and maintaining self-control, as well as a greater number of problem behaviors. Significant differences were not found between groups with regard to social participation or cognitive level of play. Significant correlations of moderate strength were found between social participation in play and social skills for the sample as a whole: total social skills score was positively related to interactive play, and negatively related to solitary play. CONCLUSION: The results suggest that the experience of maltreatment has a negative impact on children's developing interpersonal skills above and beyond the influence of factors associated with low socioeconomic status and other environmental stressors.


Subject(s)
Child Abuse/psychology , Play and Playthings , Social Behavior Disorders/psychology , Child Development , Child, Preschool , Female , Humans , Interpersonal Relations , Male , Peer Group , Social Behavior , Social Behavior Disorders/etiology
12.
Acta Psiquiatr Psicol Am Lat ; 37(4): 291-8, 1991 Dec.
Article in Spanish | MEDLINE | ID: mdl-1843597

ABSTRACT

One hundred and one depressed inpatients were treated by the authors with a second-generation antidepressive original molecule: Toloxatone, a specific and reversible MAO A inhibitor. Upon admission, all 101 patients with depressive illness did not score higher than 20 on Hamilton's Scale, and did not score lower than 4 on Fischer, Fernández Labriola and Rodríguez Casanova's Endogeneity Test. Biological profiles (Phenyl-ethylamine, NA, and MHPG) were available on 57 subjects. At the beginning of the experiment: (a) No subject was taking antidepressives, (b) Patients' age averaged 46; (c) The 6-week experiment was a double-blind vs. placebo type. Daily toloxatone dose was standardized in a 400 mg intake. Significant modifications were detected in 51 subjects. Among the 59 subjects that were administered active substance, 37 achieved either "excellent" or "good" outcomes. Biological markers pointed out a profile of patients with a better response to Toloxatone: Namely, patients with a lower noradrenergic activity. Anxiety-free depression as well as inhibited depressions are a psychiatrist's choice for administering Toloxatone.


Subject(s)
Depression/drug therapy , Oxazoles/therapeutic use , Oxazolidinones , Adolescent , Adult , Aged , Double-Blind Method , Drug Administration Schedule , Female , Humans , Male , Middle Aged , Psychiatric Status Rating Scales , Psychometrics
13.
Acta Psiquiatr. Psicol. Am. Lat ; 37(4): 291-8, 1991 Dec.
Article in Spanish | BINACIS | ID: bin-51240

ABSTRACT

One hundred and one depressed inpatients were treated by the authors with a second-generation antidepressive original molecule: Toloxatone, a specific and reversible MAO A inhibitor. Upon admission, all 101 patients with depressive illness did not score higher than 20 on Hamiltons Scale, and did not score lower than 4 on Fischer, Fernández Labriola and Rodríguez Casanovas Endogeneity Test. Biological profiles (Phenyl-ethylamine, NA, and MHPG) were available on 57 subjects. At the beginning of the experiment: (a) No subject was taking antidepressives, (b) Patients age averaged 46; (c) The 6-week experiment was a double-blind vs. placebo type. Daily toloxatone dose was standardized in a 400 mg intake. Significant modifications were detected in 51 subjects. Among the 59 subjects that were administered active substance, 37 achieved either [quot ]excellent[quot ] or [quot ]good[quot ] outcomes. Biological markers pointed out a profile of patients with a better response to Toloxatone: Namely, patients with a lower noradrenergic activity. Anxiety-free depression as well as inhibited depressions are a psychiatrists choice for administering Toloxatone.

14.
Acta Psiquiatr. Psicol. Am. Lat ; 37(4): 291-8, 1991 Dec.
Article in Spanish | BINACIS | ID: bin-38143

ABSTRACT

One hundred and one depressed inpatients were treated by the authors with a second-generation antidepressive original molecule: Toloxatone, a specific and reversible MAO A inhibitor. Upon admission, all 101 patients with depressive illness did not score higher than 20 on Hamiltons Scale, and did not score lower than 4 on Fischer, Fernández Labriola and Rodríguez Casanovas Endogeneity Test. Biological profiles (Phenyl-ethylamine, NA, and MHPG) were available on 57 subjects. At the beginning of the experiment: (a) No subject was taking antidepressives, (b) Patients age averaged 46; (c) The 6-week experiment was a double-blind vs. placebo type. Daily toloxatone dose was standardized in a 400 mg intake. Significant modifications were detected in 51 subjects. Among the 59 subjects that were administered active substance, 37 achieved either [quot ]excellent[quot ] or [quot ]good[quot ] outcomes. Biological markers pointed out a profile of patients with a better response to Toloxatone: Namely, patients with a lower noradrenergic activity. Anxiety-free depression as well as inhibited depressions are a psychiatrists choice for administering Toloxatone.

15.
Percept Mot Skills ; 67(2): 395-8, 1988 Oct.
Article in English | MEDLINE | ID: mdl-3217184

ABSTRACT

This study explored the correlations among nonverbal reasoning ability, creativity, and academic achievement in gifted minority children, 89 girls and 71 boys in Grades 1 through 8 in a program for gifted. A random half of students from all grade levels were tested at the beginning of the year and the remaining half after 7 mo. with Raven Progressive Matrices, Torrance Tests of Creative Thinking, and the California Achievement Test. Pearson correlations reflected limited relations among these variables except for a significant positive value between creativity and reading achievement. Suggestions for further study and implications for identification procedures and program development were provided.


Subject(s)
Achievement , Child, Gifted/psychology , Creativity , Hispanic or Latino/psychology , Adolescent , Child , Female , Humans , Male , Reading , United States
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