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1.
Carbohydr Polym ; 144: 25-32, 2016 Jun 25.
Article in English | MEDLINE | ID: mdl-27083789

ABSTRACT

In this work we develop poly(L-lactide)/branched ß-cyclodextrin (bßCD) blends in an attempt to obtain new biocompatible and biodegradable materials to be used in the emerging fields of pharmaceutical, biomedicine and food industry. Ionic branched ß-cyclodextrin (bßCD) was obtained by polycondensation of the ß-CD monomer and it was blended with a commercially available PLLA. Fourier transform infrared spectroscopy (FTIR) has been applied to study the occurring interactions between both partners. Thermal properties of blends have been analyzed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), while the phase structure of the blends was analyzed by scanning electron microscopy (SEM). Finally, dynamic mechanical analysis (DMA) has been used to provide further insights into the features controlling miscibility between PLLA and bßCD. Results show the presence of a single phase irrespectively of the blend composition. Overall, this work opens new perspectives for the development of naturally available materials with tunable functional properties for applications in which cyclodextrins emerge as a new class of promising candidates.


Subject(s)
Polyesters/chemistry , beta-Cyclodextrins/chemistry , Calorimetry, Differential Scanning , Epichlorohydrin/chemistry , Hydrophobic and Hydrophilic Interactions , Mechanical Phenomena , Microscopy, Electron, Scanning , Proton Magnetic Resonance Spectroscopy , Spectroscopy, Fourier Transform Infrared , Stereoisomerism , Surface Properties , Temperature , beta-Cyclodextrins/chemical synthesis
2.
Rev. arg. morfol ; 2(1): 12-16, 2013.
Article in Spanish | LILACS | ID: lil-733605

ABSTRACT

Un hábito es cualquier acto adquirdo mediante la experiencia y realizado regular e inconscientemente,y sobre los que el sujeto tiene poco control voluntario.Los denominados parafuncionales, originan a nivel de tejidos blandos, alteraciones de la normalidadmorfológica visualizables como lesiones. Se ha referido que la queilofagia (el hábito de morderse los labios), si bien no es frecuente, puede verse influenciada por factores condicionantes como el estilo de vida, la calidad de la relación intrafamilar, estrés, frustración o inmadurez emocional por fijación ante una falta de evolución apartir de la etapa oral psicosocial de Freud. Dado losúltimos reportes respecto a una mayor prevalencia delhábito entre individuos privados de libertad, con condiciones de supervivencia bajo strés, violencia, hacinamiento, malos hábitos, alimentación inadecuada, etc,se presenta una revisión y actualización de este tópico y su potencial valor como elemento morfológico para la perfilación criminal en la investigación forense.


A habit is an act acquired by means of the experience and realized constant and unconsciously, and on that he subject has minimal voluntary control. The caled as parafunctionals, originate alterations of the morphologic normality of soft isues, and can be sen as injuries. Cheilophagia (the habit of excesive bitng of the lips), though it is not frequent, being able turnsinfluenced by determining factors as the way of life, the quality of the parental relationship, stres, frustration oremotional immaturity for fixation before a lack of evolution from the oral stage Freud's psicosocial. Since the lastreports about he major prevalence of the habit betwen individuals in custody with conditons of survival sufering stres, violence, overcrowding, bad habits, inadequate feding, we present a review and update of this topic and its potential value as a morphologic evidence to profilng and the forensic investigation.


Subject(s)
Humans , Male , Female , Cheilitis , Forensic Dentistry , Lip Diseases
3.
Rev. arg. morfol ; 2(1): 12-16, 2013.
Article in Spanish | BINACIS | ID: bin-129791

ABSTRACT

Un hábito es cualquier acto adquirdo mediante la experiencia y realizado regular e inconscientemente,y sobre los que el sujeto tiene poco control voluntario.Los denominados parafuncionales, originan a nivel de tejidos blandos, alteraciones de la normalidadmorfológica visualizables como lesiones. Se ha referido que la queilofagia (el hábito de morderse los labios), si bien no es frecuente, puede verse influenciada por factores condicionantes como el estilo de vida, la calidad de la relación intrafamilar, estrés, frustración o inmadurez emocional por fijación ante una falta de evolución apartir de la etapa oral psicosocial de Freud. Dado losúltimos reportes respecto a una mayor prevalencia delhábito entre individuos privados de libertad, con condiciones de supervivencia bajo strés, violencia, hacinamiento, malos hábitos, alimentación inadecuada, etc,se presenta una revisión y actualización de este tópico y su potencial valor como elemento morfológico para la perfilación criminal en la investigación forense.(AU)


A habit is an act acquired by means of the experience and realized constant and unconsciously, and on that he subject has minimal voluntary control. The caled as parafunctionals, originate alterations of the morphologic normality of soft isues, and can be sen as injuries. Cheilophagia (the habit of excesive bitng of the lips), though it is not frequent, being able turnsinfluenced by determining factors as the way of life, the quality of the parental relationship, stres, frustration oremotional immaturity for fixation before a lack of evolution from the oral stage Freuds psicosocial. Since the lastreports about he major prevalence of the habit betwen individuals in custody with conditons of survival sufering stres, violence, overcrowding, bad habits, inadequate feding, we present a review and update of this topic and its potential value as a morphologic evidence to profilng and the forensic investigation.(AU)


Subject(s)
Humans , Male , Female , Lip Diseases , Cheilitis , Forensic Dentistry
4.
Rev Sci Instrum ; 80(6): 065103, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19566222

ABSTRACT

In the last decade, radiochromic films (RCF) have been used extensively in medical physics for evaluating uniformity of radiation beams and dose distributions. These films are very sensitive to changes in temperature; therefore, one needs to know its thermal behavior to use them efficiently. Normally, the thermal assessment is done using optical methods on previously irradiated samples. Here, we report the use of a complementary dielectric method. We designed an experimental device that allows us to measure, simultaneously, the dielectric and optical properties as a function of temperature. We performed the measurements in real-time to temperature increases from 27 to 48 degrees C of EBT and MD-55 RCF previously exposed to UV. We found for both films a decrease in the real part of the dielectric permittivity as the temperature increases, but an increment and decrease in the dielectric loss factor for the EBT and MD-55 film, respectively.


Subject(s)
Electricity , Equipment and Supplies , Film Dosimetry/instrumentation , Optics and Photonics , Temperature , Electric Capacitance , Equipment Design , Spectrum Analysis , Time Factors , Ultraviolet Rays
5.
Br J Psychiatry ; 194(2): 181-2, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19182184

ABSTRACT

Individuals seeking help from prodromal services may have been experiencing attenuated psychotic features and psychosocial impairments for a long period prior to referral. The effect of an extended duration of these untreated ;at risk' symptoms on patients' long-term functional outcome was assessed in a 12-month longitudinal observational study (n=49). A longer duration of untreated ;at risk' symptoms was correlated with a reduced improvement in Global Assessment of Functioning scores after 12 months (beta=-0.375, P=0.008). This effect was independent of age and gender and may have implications for the improvement of treatment strategies in pre-psychotic phases.


Subject(s)
Psychotic Disorders/epidemiology , Referral and Consultation/statistics & numerical data , Schizotypal Personality Disorder/epidemiology , Adolescent , Adult , Epidemiologic Methods , Female , Humans , Male , Psychiatric Status Rating Scales , Psychotic Disorders/prevention & control , Psychotic Disorders/psychology , Young Adult
6.
Biotechnol Bioeng ; 74(6): 539-43, 2001 Sep 20.
Article in English | MEDLINE | ID: mdl-11494222

ABSTRACT

A photosystem for solar energy conversion, comprised of a culture of green microalgae supplemented with methyl viologen, is proposed. The capture of solar energy is based on the Mehler reaction. The reduction of methyl viologen by the photosynthetic apparatus and its subsequent reoxidation by oxygen produces hydrogen peroxide. This is a rich-energy compound that can be used as a nonpollutant and efficient fuel. Four different species of green microalgae, Chlamydomonas reinhardtii (21gr) C. reinhardtii (CW15), Chlorella fusca, and Monoraphidium braunii, were tested as a possible biocatalyst. Each species presented a different efficiency level in the transformation of energy. Azide was an efficient inhibitor of the hydrogen peroxide scavenging system while maintaining photosynthetic activity of the microalgae, and thus significantly increasing the production of the photosystem. The strain C. reinhardtii (21gr), among the species studied, was the most efficient with an initial production rate of 185 micromol H(2)O(2)/h x mg Chl and reaching a maximum of 42.5 micromol H(2)O(2)/mg Chl when assayed in the presence of azide inhibitor.


Subject(s)
Chlorophyta/metabolism , Hydrogen Peroxide/metabolism , Photosynthesis , Animals , Chlamydomonas reinhardtii/metabolism , Chlorella/metabolism , Hydrogen-Ion Concentration , Models, Chemical , Oxygen/metabolism , Time Factors
7.
Bioresour Technol ; 78(1): 55-61, 2001 May.
Article in English | MEDLINE | ID: mdl-11265789

ABSTRACT

Some aspects of the suitability of alginate beads entrapping Chlamydomonas reinhardtii cells for nitrate consumption from nitrate-containing waters were studied and discussed. Among 14 different metal cations tested as gel bead stabilizing agents, only calcium and barium formed beads showing nitrate-consuming activity. Pure calcium alginate cell entrapment resulted in the most suitable method for active cell immobilization compared to alginate-composite-gel beads based on poly-vinylcaprolactam (PVCL) and poly-vinylpyrrolidone (PVP). To perform a continuous nitrate consumption process, calcium alginate-entrapped cells were first grown in a 2.5 l airlift-loop reactor. A cell loading of about 150 microg Chl. g(-1) gel was achieved. Afterwards, five days nitrate consumption processes were performed and three different dilution rates were applied: (i) D < mu; (ii) D = mu; (iii) D > mu, where mu is the specific growth rate (h(-1)). The maximum consumption rates calculated for each dilution rate were: (i) 3.8, (ii) 6.4 and (iii) 7.2 mg nitrate mg(-1) Chl. h(-1). For low dilution rates (D < mu) some nitrite (< 300 microM) was excreted into the culture medium. However, this concentration of nitrite was not high enough to inhibit nitrate consumption.


Subject(s)
Chlamydomonas reinhardtii/metabolism , Nitrates/metabolism , Water Pollutants, Chemical/metabolism , Alginates , Animals , Biodegradation, Environmental , Bioreactors , Cations , Cells, Immobilized , Chlamydomonas reinhardtii/growth & development , Gels , Glucuronic Acid , Hexuronic Acids
8.
J Food Prot ; 64(1): 99-103, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11198448

ABSTRACT

In the present study, 304 samples of herbs and spices (garlic powder, cumin seeds, black pepper, oregano, and bay leaves) widely used in Mexico were analyzed for the presence of Bacillus cereus, Salmonella Typhi, Shigella dysenteriae, Escherichia coli, total and fecal coliforms, total mesophilic aerobic organisms, and fungi. Samples were nonpackaged or packaged in polyethylene bags or glass containers. High levels (10(5) to 10(7) CFU/g) of mesophilic aerobic microorganisms were found in most of the samples of garlic powder, cumin seed, and black pepper. Lower levels (<102 CFU/g) were found in oregano and bay leaves. Total and fecal coliforms counts were dependent on the type of packaging. More than 70% of the polyethylene-packaged samples had less than 10(3) CFU/g of microorganisms. Glass and nonpackaged spices showed lower levels of these microorganisms. B. cereus was present in 32 samples of which most were polyethylene packaged. The other pathogenic bacteria were not detected. Aspergillus niger was detected in 29% of the samples, Rhizopus sp. in 19%, and Penicillum sp. and Cunninghamella in 8%.


Subject(s)
Bacteria/growth & development , Food Microbiology , Fungi/growth & development , Magnoliopsida/microbiology , Spices/microbiology , Bacteria/isolation & purification , Colony Count, Microbial , Enterobacteriaceae/growth & development , Enterobacteriaceae/isolation & purification , Food Handling , Fungi/isolation & purification , Mexico
9.
Luminescence ; 15(3): 131-5, 2000.
Article in English | MEDLINE | ID: mdl-10862140

ABSTRACT

Flow injection analysis has been applied to the determination of hydrogen peroxide produced by some different species of microalgae. The method is based on the luminol-H(2)O(2) chemiluminescence reaction using Cr(III) as a catalyst. Optimum experimental conditions for the method have been studied and trace amounts of hydrogen peroxide determined with detection limits of 4 10(-8) mol/L. The method using Cr(III) was compared with that using horseradish peroxidase as the catalyst.


Subject(s)
Eukaryota/chemistry , Flow Injection Analysis/methods , Hydrogen Peroxide/analysis , Luminescent Measurements , Catalysis , Chromium , Edetic Acid , Eukaryota/metabolism , Eukaryota/radiation effects , Horseradish Peroxidase , Hydrogen Peroxide/metabolism , Luminol , Photochemistry
10.
J Acquir Immune Defic Syndr ; 25 Suppl 2: S151-6, 2000 Dec 15.
Article in English | MEDLINE | ID: mdl-11256736

ABSTRACT

With the many recent improvements in the medical management of HIV, the benefits of early detection of the virus have increased. People found to be HIV-positive can be offered immediate referrals for medical care and a comprehensive continuum of services. However, it is estimated that, among the 650,000 to 900,000 seropositive persons in the United States, about one third are unaware of their serostatus. Many of those who are tested for HIV do not return for their results. Among those less likely to return for results are young people and black Americans. Many factors at the individual, system and societal levels negatively impact whether individuals at risk for HIV seek HIV testing in the first place, whether they return for their results, and whether they get appropriate care after they are found to be HIV-positive. Some solutions are offered to improve the identification of new HIV infections. These include social marketing campaigns to encourage individuals to be tested for HIV. Also, more use of the rapid HIV test, which will substantially increase the number of people obtaining their HIV results, is recommended. New computer technologies, such as telemedicine, also have the potential to improve linkages to care for newly diagnosed individuals. In addition, it is essential that HIV care continue to be readily available through the Ryan White Care Act.


Subject(s)
HIV Seropositivity/diagnosis , HIV/immunology , Health Services Accessibility , Adolescent , Adult , Confidentiality/psychology , Female , HIV Seropositivity/drug therapy , HIV Seropositivity/psychology , Humans , Male , Time Factors
11.
Gastroenterol Hepatol ; 20(4): 180-3, 1997 Apr.
Article in Spanish | MEDLINE | ID: mdl-9280611

ABSTRACT

Thromboembolic complications during the course of inflammatory bowel disease are infrequent but are mainly found in young patients and are associated with a high morbimortality. The etiopathogenesis of these complications has been widely debated and the existence of coagulation alterations and fibrinolysis have been suggested. Nonetheless, the mechanism must be complex since not only do not all the patients with these alterations present this complication but neither do all the patients with thromboembolism have recognized coagulation disorders. The most common clinical presentation is deep vein thrombosis with pulmonary embolism with arterial thrombosis being rare. Five patients with Crohn's disease and two with ulcerative colitis who presented a total of new thromboembolic episodes, six arterial (1 in primitive iliac artery, 1 in common femoral artery, 1 in humeral-axillary artery, 2 in internal carotid and 1 in superior mesenteric artery) and three of venous localization (1 in brachyocephalic-subclavian trunk, 1 axillary and 1 iliac-femoral/pulmonary thromboembolism) are reported. An updated review of the etiopathogenesis, presentation, treatment and prophylaxis of the thromboembolic complications of inflammatory bowel disease is presented.


Subject(s)
Inflammatory Bowel Diseases/complications , Thromboembolism/etiology , Adult , Female , Humans , Male , Middle Aged
12.
Salud Publica Mex ; 39(6): 507-12, 1997.
Article in English | MEDLINE | ID: mdl-9477732

ABSTRACT

OBJECTIVE: To determine the prevalence of the smoking habit among Mexican physicians as well as some of their attitudes and information on specific issues concerning smoking. MATERIAL AND METHODS: In 1993, a survey was carried out among 3,568 physicians of the three major official health care institutions in Mexico City. A questionnaire designed for The Mexican National Survey of Addictions (ENA 1993) was used. Prevalence of cigarette smoking, age of onset, number of cigarettes per day; also information and attitudes concerning smoking were assessed. RESULTS: The mean age was 37, 66% were males. Of the 3,488 (98%) surveyed, 26.9% were smokers (62% daily), 20.6% were ex-smokers and 52.5% non-smokers. There were differences related to age and sex (p < 0.05). Of daily smokers, 36% smoked between 1 and 5 cigarettes. There was a significant trend among ex-smokers that linked the time they had ceased smoking with the fear to start smoking again. Physicians were well informed of the relationship between cigarette smoking and lung cancer. Over 80% considered tobacco an addictive drug but only 65% were in favor of banning smoking from their workplaces and over 10% were not aware that it is forbidden to smoke inside health care facilities. CONCLUSIONS: These results differ from other studies that find the prevalence of smoking among physicians lower than in the general population. Our study revealed a greater prevalence of the smoking habit among female physicians and the number of cigarettes smoked per day was greater than in the general population regardless of sex.


Subject(s)
Health Knowledge, Attitudes, Practice , Physicians , Smoking/epidemiology , Adult , Age Factors , Female , Humans , Male , Mexico/epidemiology , Middle Aged , Physicians, Women , Prevalence , Sex Factors , Smoking Cessation , Surveys and Questionnaires
13.
Bull Pan Am Health Organ ; 30(3): 197-205, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8897719

ABSTRACT

The study reported here, seeking to develop a simple, practical, sensitive, and inexpensive technique for microbial diagnosis of tuberculosis, used a combination of biphasic media and microculture techniques to augment the sensitivity of traditional culture methods. A total of 540 sputum samples (5 mL each) were obtained from 180 patients with suspected tuberculosis in Mexico City. These samples were treated with Hanks reagent, neutralized with 25% HCl, and centrifuged. In each case the resulting residue was combined with liquid media (Sula medium or a phosphate-buffered control solution) and was inoculated into a bottle containing a solid medium (Löwenstein-Jensen-Holm or Middlebrook). A silicone-coated slide appropriate for culture of hydrophobic mycobacteria was inserted in each bottle, and the cultures (examined weekly) were incubated at 37 degrees C until the first macroscopic bacterial growth was detected or for up to eight weeks if none was detected. When such growth was detected, or at the end of eight weeks, each slide was withdrawn from the bottle, sterilized, stained by Kinyoun's method, and examined microscopically. Following 2-4 weeks of incubation, macroscopic bacterial growth was detected in 71 bottles and was confirmed by microscopic examination of the corresponding slides. No macroscopic bacterial growth was found in any of the remaining 469 bottles, but microscopic growth was observed on 77 of the slides examined after eight weeks. The authors conclude that this method represents a noteworthy improvement over standard culture methods in terms of bacterial isolation and suggest that its case, economy, and practicality make it suitable for application in developing countries.


Subject(s)
Cell Culture Techniques/methods , Mycobacterium tuberculosis/isolation & purification , Silicon , Cell Culture Techniques/economics , Culture Media , Humans , Sensitivity and Specificity , Statistics, Nonparametric
14.
Rev Esp Enferm Dig ; 88(7): 513-5, 1996 Jul.
Article in Spanish | MEDLINE | ID: mdl-8924332

ABSTRACT

We report the case of a 27-year-old man with alcoholic acute pancreatitis, who developed an acute loss of visual acuity; a bilateral Purtscher's retinopathy, a rare complication of acute pancreatitis, was confirmed by ophthalmoscopy.


Subject(s)
Pancreatitis, Alcoholic/complications , Retinal Diseases/etiology , Adult , Humans , Male , Retinal Hemorrhage/etiology , Vision Disorders/etiology , Visual Acuity
15.
Rev Esp Enferm Dig ; 88(3): 221-2, 1996 Mar.
Article in Spanish | MEDLINE | ID: mdl-8645518

ABSTRACT

Sarcoidosis is a granulomatous disease of unknown origin with a variable clinical presentation. Although involvement of every organ has been described, the pulmonary system is most frequently involved. Isolated extrapulmonary disease is rare. Hepatic manifestations include granulomatous hepatitis and hilar lymphadenopathy. We describe a case of sarcoidosis initially presenting as extrahepatic jaundice.


Subject(s)
Liver Diseases/diagnosis , Pancreatic Neoplasms/diagnosis , Sarcoidosis/diagnosis , Adult , Cholestasis/etiology , Diagnosis, Differential , Female , Humans , Liver Diseases/complications , Sarcoidosis/complications , Tomography, X-Ray Computed
16.
Rev Invest Clin ; 47(5): 365-9, 1995.
Article in Spanish | MEDLINE | ID: mdl-8584806

ABSTRACT

A conversion index (CI) which measures the efficiency of utilization of dietary energy was found to be normally distributed in Wistar rats. The CI used was a ratio of the amount of food ingested to achieve an increment of one gram of body weight during the period of 32 days starting on day 21 after weaning. We have previously reported that male rats are more efficient energy converters than females. As a way to explore the hypothesis that the inheritance of the regulation of energy requirements is multifactorial, we mated F1 rats with high CI (poor energy converters) and studied the CI of their F2 offspring. The males behaved in agreement with the hypothesis as the F2 males had higher CI than the F1 males, but the behavior in females was different, i.e. the F2 were better converters than the F1. We have no explanation for this gender discrepancy.


Subject(s)
Energy Metabolism/genetics , Animals , Basal Metabolism/genetics , Crosses, Genetic , Energy Intake , Female , Growth/genetics , Male , Rats , Rats, Wistar , Sex Characteristics , Weight Gain/genetics
17.
Arch Med Res ; 26 Spec No: S145-8, 1995.
Article in English | MEDLINE | ID: mdl-8845639

ABSTRACT

In Wistar rats the conversion indexes (CIs) are normally distributed. A conversion index is the amount of food consumed necessary to increase the body weight by 1 g in a 32-day period, which begins at weaning (day 21) and ends on the 52nd day of life of the rat. Some experiments have been designed trying to demonstrate that inheritance of energy dietary utilization in Wistar rats may be multifactorial modulated by gender. In the study presented here parental males (F1) with CIs below the male median were paired with females of the same F1 who also had CIs below the female median. It was postulated, if the hypothesis is correct, that the offspring (F2) obtained from these pairings would have conversion indexes below the median of the CIs of the parental rats(F1). The results indicate precisely that both males and females behave as expected. Thus it appears that inheritance of efficiency of dietary energy utilization in the Wistar rat is a multifactorial trait.


Subject(s)
Body Weight/genetics , Diet , Eating/genetics , Energy Metabolism/genetics , Sex Characteristics , Animals , Female , Male , Rats , Rats, Wistar
18.
Epidemiology ; 4(1): 76-9, 1993 Jan.
Article in English | MEDLINE | ID: mdl-8420586

ABSTRACT

We conducted a matched case-control study to assess the association between epidemic asthma and soybean sensitivity in Cartagena, Spain. In skin tests, 81% of the cases and no control subjects were positive to the commercial soybean allergen; 87% of the cases and 12% of the controls were positive to the prepared soybean allergen; and 69% of the cases and 6% of the controls showed high levels of specific immunoglobulin E antibodies (odds ratio = 10; 95% confidence interval = 1.4-433). The association remained strong after adjustment for total immunoglobulin E and for 28 other allergens. The results indicate that soybean sensitivity may be causing asthma epidemics in Cartagena.


Subject(s)
Asthma/epidemiology , Disease Outbreaks , Glycine max , Respiratory Hypersensitivity/epidemiology , Adolescent , Adult , Asthma/etiology , Cross-Sectional Studies , Female , Humans , Incidence , Male , Middle Aged , Respiratory Hypersensitivity/etiology , Spain/epidemiology
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