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1.
Epidemiol Infect ; 147: e71, 2019 01.
Article in English | MEDLINE | ID: mdl-30869023

ABSTRACT

We investigated the distribution of comorbidities among adult tuberculosis (TB) patients in Chiapas, the poorest Mexican state, with a high presence of indigenous population, and a corridor for migrants from Latin America. Secondary analysis on 5508 new adult TB patients diagnosed between 2010 and 2014 revealed that the most prevalent comorbidities were diabetes mellitus (DM; 19.1%) and undernutrition (14.4%). The prevalence of DM in these TB patients was significantly higher among middle aged (41-64 years) compared with older adults (⩾65 years) (38.6% vs. 23.2%; P < 0.0001). The prevalence of undernutrition was lower among those with DM, and higher in communities with high indigenous presence. Immigrants only comprised 2% of all TB cases, but were more likely to have unfavourable TB treatment outcomes (treatment failure, death and default) when compared with those born in Chiapas (29.5% vs. 11.1%; P < 0.05). Unfavourable TB outcomes were also more prevalent among the TB patients with undernutrition, HIV or older age, but not DM (P < 0.05). Our study in Chiapas illustrates the challenges of other regions worldwide where social (e.g. indigenous origin, poverty, migration) and host factors (DM, undernutrition, HIV, older age) are associated with TB. Further understanding of these critical factors will guide local policy makers and health providers to improve TB management.


Subject(s)
Diabetes Mellitus/epidemiology , Human Migration/statistics & numerical data , Indians, North American/statistics & numerical data , Indigenous Peoples/statistics & numerical data , Malnutrition/epidemiology , Tuberculosis/epidemiology , Adult , Aged , Aged, 80 and over , Alcoholism/epidemiology , Alcoholism/etiology , Comorbidity , Cross-Sectional Studies , Diabetes Mellitus/etiology , Female , HIV Infections/epidemiology , HIV Infections/virology , Humans , Male , Malnutrition/etiology , Mexico/epidemiology , Middle Aged , Prevalence , Risk Factors , Tuberculosis/microbiology , Young Adult
2.
Water Sci Technol ; 71(2): 211-9, 2015.
Article in English | MEDLINE | ID: mdl-25633944

ABSTRACT

Biogas produced in municipal and industrial wastewater treatment facilities (BWWF) is a resource wasted in several socio-economic contexts. BWWF-based projects are compared against energy projects using conventional electricity or natural gas (NG), following strict economic considerations that usually tip the balance in favour of conventional energy supply. This is because the economic gain associated with the environmental benefits of using small biogas sources like BWWF does not overcome the technical and financial effort required in these types of project. This paper shows a broader application of life cycle assessment (LCA) methodology to explore opportunities for positive (or effective) utilization of BWWF in the Colombian context. LCA has been used to evaluate the supply-chain of NG which is the direct competitor of BWWF, in three different Colombian regions, in order to identify those where higher NG environmental impacts offer increased environmental added-value to BWWF use. LCA was also applied to study two BWWF valorization scenarios in the poultry processing industry. It shows how valorization options for BWWF are more realistic and effective when specific-regional loads are applied to the environmental assessment of NG supply-chain and BWWF valorization.


Subject(s)
Biofuels/analysis , Biotechnology/methods , Waste Products/analysis , Wastewater/chemistry , Biotechnology/instrumentation , Colombia , Environment
3.
Bioresour Technol ; 101(7): 2443-9, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19944602

ABSTRACT

Flameless combustion technology has proved to be flexible regarding the utilization of conventional fuels. This flexibility is associated with the main characteristic of the combustion regime, which is the mixing of the reactants above the autoignition temperature of the fuel. Flameless combustion advantages when using conventional fuels are a proven fact. However, it is necessary to assess thermal equipments performance when utilizing bio-fuels, which usually are obtained from biomass gasification and the excreta of animals in bio-digesters. The effect of using biogas on the performance of an experimental furnace equipped with a self-regenerative Flameless burner is reported in this paper. All the results were compared to the performance of the system fueled with natural gas. Results showed that temperature field and uniformity are similar for both fuels; although biogas temperatures were slightly lower due to the larger amount of inert gases (CO(2)) in its composition that cool down the reactions. Species patterns and pollutant emissions showed similar trends and values for both fuels, and the energy balance for biogas showed a minor reduction of the efficiency of the furnace; this confirms that Flameless combustion is highly flexible to burn conventional and diluted fuels. Important modifications on the burner were not necessary to run the system using biogas. Additionally, in order to highlight the advantages of the Flameless combustion regime, some comparisons of the burner performance working in Flameless mode and working in conventional mode are presented.


Subject(s)
Biofuels/analysis , Fossil Fuels/analysis , Incineration/instrumentation , Carbon Dioxide/analysis , Carbon Monoxide/analysis , Energy-Generating Resources , Methane/analysis , Nitrates/analysis , Oxygen/analysis , Temperature
4.
Bioing fís med cuba ; 4(3)nov.-dic. 2003. tab, graf
Article in Spanish | CUMED | ID: cum-24393

ABSTRACT

En el trabajo se presentan las principales características de diseño de un desfibrilador externo bifásico cubano, que se desarrolla por los autores. Se describen la arquitectura, los principales requisitos de seguridad y las pruebas realizadas al equipo. Finalmente se hace referencia al ensayo del prototipo de desfibrilador en un modelo porcino. Se presentan los resultados y se concluye que el equipo, que está dirigido al tratamiento del paro cardiaco por fibrilación ventricular, puede ser también aplicado con elevada seguridad a la cardioversión de pacientes con determinadas patologías(AU)


Subject(s)
Equipment Design , Ventricular Fibrillation , Equipment Safety
5.
Anal Chem ; 68(22): 4033-43, 1996 Nov 15.
Article in English | MEDLINE | ID: mdl-8916455

ABSTRACT

Infrared multiphoton photodissociation (IRMPD) is combined with stored wave form inverse Fourier transforms (SWIFT) to effect dissociation and ion ejection in a quadrupole ion trap mass spectrometer. The application of IRMPD to the structural characterization of biochemical ions generated by chemical ionization and electrospray ionization and the feasibility of utilizing infrared photons for the activation of laser-desorbed metal ion-crown ether complexes was examined. The effect of helium pressure on the dissociation efficiency and relative dissociation rate constants for systems with well-known thermochemistry was evaluated. The helium pressure is not detrimental to the IRMPD experiment when nominal pressures lower than 2 x 10(-5) Torr are used. At pressures close to nominally 8 x 10(-5) Torr of helium, collisonal deactivation dominates. Results show conventional CAD is a more selective dissociation technique; however, the amount of fragment ion information generated depends highly on the qz value. IRMPD, on the other hand, is independent of the value of qz such that low rf storage values can be utilized during the irradiation period. Thus, under these conditions, informative lower mass fragment ions are trapped and detected. A larger number of structurally informative fragments is generated upon irradiation with infrared photons relative to the CAD method because of the further excitation of primary fragment ions upon photoabsorption. SWIFT wave forms are successfully utilized to determine the extent of excitation of primary fragment ions as well as prove/disprove dissociation pathways of a variety of ions such as macrolide antibiotics and hydrogen-bonded complexes.


Subject(s)
Mass Spectrometry/instrumentation , Lasers , Mass Spectrometry/methods , Photons , Spectroscopy, Fourier Transform Infrared
6.
J Mass Spectrom ; 31(4): 403-10, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8799285

ABSTRACT

Barbiturates are a class of drugs that are utilized as anesthetics and sleeping agents and are used for the treatment of anxiety, epilepsy and other psychiatric disorders. Because of their pyrimidine structures, barbiturates are highly basic compounds. The evaluation of the formation of adducts involving the borinium ion, B(OCH3)2+, and the barbiturates in a quadrupole ion trap is described. The adducts [M + 73]+ dissociate by elimination of methanol followed by the attachment of a trimethylborate or water molecule. This multi-step pathway is characteristic of a basic, nitrogen-containing structure that has at least one acidic hydrogen. Model compounds were used to probe the nature of this unusual reaction pathway, which involves nucleophilic attack by a methoxyl oxygen of neutral trimethyl borate at the boron atom of the adduct.


Subject(s)
Barbiturates/chemistry , Boron/chemistry , Borates/chemistry , Indicators and Reagents , Mass Spectrometry , Protons , Stereoisomerism
7.
J Am Soc Mass Spectrom ; 7(11): 1116-25, 1996 Nov.
Article in English | MEDLINE | ID: mdl-24203074

ABSTRACT

A simple energy-resolved mass spectrometric technique is described for the estimation of critical energies for dissociation of ions via threshold collisional activation measurements in a quadrupole ion trap. The method is calibrated by using compounds with well-defined dissociation energies, and separate calibration curves must be constructed for radical ions that are bound by covalent bonds versus hydrogen-bonded complexes. For these sets of experiments, the threshold point is defined as the activation voltage required for the fragment ion intensity to be 10% of the total ion intensity. A plot of threshold activation voltage of the calibrant versus literature critical energies shows a near-linear function, and accuracies are estimated as better than ± 6 kcal/mol. The q z value during activation seems to have little effect on the threshold voltages as long as very low q z values that cause ion ejection are avoided. Activation periods that are substantially longer than 10-ms result in nonlinear behavior in the calibration curves for ions that have critical energies above 30 kcal/mol. This energy-resolved method was also useful for the estimation of critical energies of complexes bound by electrostatic forces, such as hydrogen-bonding interactions. A quantitative evaluation of proton-bound polyether-amine complexes showed that the number of available hydrogen-binding sites, the gas-phase basicities of the polyether and amine components, and the ability of the complex to attain the most favorable near-linear hydrogen bonds correlate with the threshold values.

8.
Anal Chem ; 66(14): 2330-5, 1994 Jul 15.
Article in English | MEDLINE | ID: mdl-8080107

ABSTRACT

A new combination of collisionally activated dissociation and ion-molecule reactions in a quadrupole ion trap mass spectrometer is developed for the class-selective determination of 4-quinolones, an important group of antibiotics. In this method, collisionally activated dissociation is used to promote dehydration of each protonated quinolone, and the resulting dehydrated fragment ion undergoes an addition reaction with an auxiliary reagent. The auxiliary reagents, including acetone, acetic anhydride, and n-propylamine, have structures that specifically allow formation of a cyclic adduct with the analyte ion. This sequential process is characteristic of a class of analyte molecules that have adjacent carboxylic acid and ketone functional groups anchored on a rigid ring and undergo facile, efficient dehydration.


Subject(s)
Anti-Infective Agents/chemistry , 4-Quinolones , Indicators and Reagents , Mass Spectrometry
9.
J Pharmacol Methods ; 26(1): 73-7, 1991 Aug.
Article in English | MEDLINE | ID: mdl-1921411

ABSTRACT

The croton oil ear test is widely used to identify prospective topical antiinflammatory drugs. Ear inflammation is produced by applying a 2% solution of croton oil on the ears of mice or rats. The effectiveness of the drug that is dissolved in the croton oil solution can be gauged by comparing the croton oil treated ears with the croton oil plus drug treated ears. The effect is measured following sacrifice of the animal by weighing either the excised ear (Tonelli et al., 1965; Glenn et al., 1978; Swingle et al., 1981; Soliman et al., 1983; Mantione and Rodriguez 1990) or a plug taken from the ear (Tubaro et al., 1985; Davis et al., 1989a; Davis et al., 1989b). Use of this technique for the generation of a time-course evaluation of antiinflammatory activity requires a large amount of the chemical to be tested and the sacrifice of many animals. In other assays, ear thickness has been measured by caliper (Carlson et al., 1985; Maloff et al., 1989) or by dial micrometer (Griswold et al., 1987), which allow multiple measurements to be made, but the pressure on the ear was not reported. In a recent review of pharmacological methods, Chang and Lewis (1989) caution that using calipers to measure ear thickness is subject to operator error and bias. Furthermore, they emphasize care must be taken to not leave the calipers in contact with the ear too long, as it is possible to squeeze substantial amounts of edema fluid out of the ear tissue.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Ear/pathology , Inflammation/pathology , Animals , Anti-Inflammatory Agents , Croton Oil , Dose-Response Relationship, Drug , Hydrocortisone/pharmacology , Inflammation/chemically induced , Mice , Rats
10.
Ginecol Obstet Mex ; 45(270): 319-28, 1979 Apr.
Article in Spanish | MEDLINE | ID: mdl-456925

ABSTRACT

PIP: The results of 1393 cases of female sterilization are presented in the article. Several techniques of tubal ligation were employed, postpartum and postabortum minilaparotomy, Pomeroy method, and fimbriectomy. Operative procedures are given in details for every technique. Main reason for sterilization was permanent contraception; 92% of patients belonged to low socioeconomic classes, were about 34 years old, with parity over 5, and most with antecedents of abortion and of cesarean section. There were no complications; late morbidity was only 1.47%, and mainly caused by transvaginal surgery. Minilaparotomy was found to give better results than conventional laparotomy; average time for the procedure was 10'. Hospital stay was 3.2 days, and paracervical block was used in over 92% of cases.^ieng


Subject(s)
Sterilization, Tubal/methods , Adolescent , Adult , Family Planning Services , Female , Humans , Middle Aged , Pregnancy , Socioeconomic Factors , Spain
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