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1.
PLoS One ; 18(11): e0288885, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37976256

RESUMO

BACKGROUND: This research was focused on measuring the TFP bioeconomy post-Covid-19 in six regions of the world. METHODS: The panel data was organized with FAO Statistics data. Linear programming with an enveloping data analysis (DEA) approach was used to measure the Malmquist TFP indices to determine the inter-annual productivity and technical efficiency changes by region. RESULTS: The results show that the effect of Covid-19 on the bioeconomy productivity during the period 2012-2021 on average decreased by 11.6%. This effect was explained by the decomposition of the productivity change into the changes in technical efficiency. The workers decreased their efficiency by 11.7%. In the Northern American region, it decreased by 21.6%, in the Southern European region by 10.1, and in Western Europe by 11.7%. CONCLUSION: The results show a downward trend that was affected in the year 2019 by Covid-19, however, it was possible to recover in the following year. One of the conclusions of these results is the effect of the immediate strategies that the governments of the region implemented. This effect was a little slower in the North American, Southeastern, and Eastern European regions. Finally, it is concluded that the measures implemented by the governments in the studied regions had an increasing effect in conditions of variable scale returns. In other words, the companies that remained on a constant scale decreased.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Agricultura , Eficiência , Europa (Continente)/epidemiologia , China
2.
F1000Res ; 12: 30, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38919837

RESUMO

Background: The research focused on evaluating the biological and reproductive parameters of the species Spodoptera sunia with the introduction of field genetic material, in the Noctuid Insect Breeding Laboratory. Methods: The experiment consisted of three treatments and three repetitions involving 30 individuals each. Field-collected S. sunia population was reared in the laboratory under semi-controlled conditions of temperature and humidity for three generations. The progeny of the third generation was crossed with the laboratory population and the resulting progeny was observed for growth and reproductive fitness. Results: The results revealed that the hybrid progeny (T3) has a sex ratio (F: M) of 0.82, as against 1.22 and 0.76 observed in the field (T1) and lab populations (T2) respectively. The T1 females oviposited 196 egg masses as against 160 and 59 egg masses by T3 and T2 females respectively. The larval growth was more in hybrid progeny with shorter larval duration. However, no variation was observed in the incubation and pupal periods. Conclusions: Since the most optimal results were obtained in T2 and T3, it is recommended to introduce genetic material every six months to maintain a good laboratory population of the insect host under study and better breeding of its natural enemies.


Assuntos
Larva , Animais , Feminino , Masculino , Larva/crescimento & desenvolvimento , Oviposição , Spodoptera/fisiologia , Cruzamentos Genéticos , Reprodução , Aptidão Genética , Laboratórios , Razão de Masculinidade
3.
F1000Res ; 11: 1300, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-39148496

RESUMO

Background: This study focused on evaluating the diversity and richness of the edaphic macrofauna in eight banana farms in the western zone of Nicaragua. Methods: The sampling design was random and descriptive, it was divided into two phases, the first was the collection of the sample, and the second was the classification, coding, and storage of the extracted macrofauna populations. The sampling method employed included the extraction of soil and litter samples. Soil samples were collected using a wooden frame (monolith), with each sample weighing approximately 1 kilogram and taken from a depth of 0.20 cm. Litter samples were collected from the soil surface. A total of 80 samples were collected, with 40 soil samples and 50 litter samples obtained across the 8 plantain farms. Results: The results showed that the relative abundance of biodiversity was higher in the 0-20 cm soil depth stratum than in the branch and leaf biomass strata. The values of the diversity indices of Simpson's Dominance, Shanon, Margalef, and Equity were in the normal range, with a tendency towards low diversity. Likewise, in the richness of species, the Dominance or most abundant genus were earthworms (Oligochaeta) and Hymenoptera ( Solenopsis, Leptothorax, Camponotus, Pheidole), indicating the directly proportional relationship, that is to say, that the greater the number of earthworms the production increases and the greater the number of Hymenoptera it decreases, confirmed with the Pearson correlation coefficient with a reliability of 95%. Conclusions: It was concluded that based on the estimates of the diversity indicators, two detritivore genus (earthworms and Hymenoptera) were the ones with the more dominance, being important in the production of the banana agrosystem due to the decomposition of organic matter and its nutritional contribution to the plant. We observed a direct correlation with earthworms and an indirect relationship with Hymenoptera.

4.
Int J Mol Sci ; 22(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201769

RESUMO

Hyaluronic acid (HA) and gelatin (Gel) are major components of the extracellular matrix of different tissues, and thus are largely appealing for the construction of hybrid hydrogels to combine the favorable characteristics of each biopolymer, such as the gel adhesiveness of Gel and the better mechanical strength of HA, respectively. However, despite previous studies conducted so far, the relationship between composition and scaffold structure and physico-chemical properties has not been completely and systematically established. In this work, pure and hybrid hydrogels of methacroyl-modified HA (HAMA) and Gel (GelMA) were prepared by UV photopolymerization and an extensive characterization was done to elucidate such correlations. Methacrylation degrees of ca. 40% and 11% for GelMA and HAMA, respectively, were obtained, which allows to improve the hydrogels' mechanical properties. Hybrid GelMA/HAMA hydrogels were stiffer, with elastic modulus up to ca. 30 kPa, and porous (up to 91%) compared with pure GelMA ones at similar GelMA concentrations thanks to the interaction between HAMA and GelMA chains in the polymeric matrix. The progressive presence of HAMA gave rise to scaffolds with more disorganized, stiffer, and less porous structures owing to the net increase of mass in the hydrogel compositions. HAMA also made hybrid hydrogels more swellable and resistant to collagenase biodegradation. Hence, the suitable choice of polymeric composition allows to regulate the hydrogels´ physical properties to look for the most optimal characteristics required for the intended tissue engineering application.


Assuntos
Materiais Biocompatíveis/química , Gelatina/química , Ácido Hialurônico/química , Hidrogéis/química , Metacrilatos/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Humanos , Polímeros/química
5.
Fish Physiol Biochem ; 46(1): 23-37, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31401709

RESUMO

Determination of the main nutritional requirements at different developmental stages is a prerequisite in the formulation of feeds for newly cultured fish species. In the present study, the lipid and protein requirements of larvae of a native Mexican fish, the three-spot cichlid Cichlasoma trimaculatum, were assessed using a two-factor experimental design that considered four protein (35, 40, 45, and 50%) and two lipid levels (16 and 22%) on growth, survival, and digestive enzyme activities. The best growth and feed efficiency results were obtained when larvae were fed diets including 45% protein and 22% lipids. Comprehensive evaluation of the profile of digestive enzymes using multivariate analysis also demonstrated significant differences in nutritional condition generated by varying inclusion of nutrients. Thus, an increase in protein led to an increase in alkaline protease activity and a reduction in leucine aminopeptidase activity, and the reduction of dietary lipid content led to a significant increase in lipase and trypsin enzymatic activities. Based on our results, C. trimaculatum larvae have a high capacity to hydrolyze both nutrients (protein and lipids) for the high digestive enzyme activities and increase their growth, particularly with a diet containing 45% protein and 22% lipids.


Assuntos
Ciclídeos/fisiologia , Dieta , Gorduras na Dieta , Proteínas Alimentares , Animais , Ciclídeos/metabolismo , Lipase , Lipídeos , Proteínas , Tripsina
6.
Dose Response ; 16(2): 1559325818777930, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29872370

RESUMO

The use of radioactive emanations has been of great importance for the performance of endourology procedures, such as percutaneous nephrolithotomy (NLP). The damage to health caused by radiation has been a sensitive issue. The objective of this work was to determine the dose received by the surgeon during NLP and the total dose generated by the fluoroscope. A cross-sectional study was conducted with data from a cohort study with a duration of 18 months that included 101 patients. Radiation was measured with dosimeter during the last 6 months. During the last 6 months of the study, 34 patients were submitted to surgery. The average age was 47 years. Average fluoroscopy time was 58.3 second (24-122 seconds) in both male and female groups, with 57.16 seconds and 58.95 seconds per case, respectively (P = .6). Radiation emitted during 6 months for the 34 patients was 330.5 mGy. The total radiation measured by the dosimeter was 1 mSv, which is equivalent to 0.3% of the total radiation applied during the procedures. Doses measured by the dosimeter on the surgeon were within the recommended annual doses although dose received by the hands exceeds the authorized limits (500 mSv/y).

7.
Allergol Immunopathol (Madr) ; 46(3): 291-303, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29288048

RESUMO

BACKGROUND: With the availability of high-quality asthma guidelines worldwide, one possible approach of developing a valid guideline, without re-working the evidence, already analysed by major guidelines, is the ADAPTE approach, as was used for the development of National Guidelines on asthma. METHODS: The guidelines development group (GDG) covered a broad range of experts from medical specialities, primary care physicians and methodologists. The core group of the GDG searched the literature for asthma guidelines 2005 onward, and analysed the 11 best guidelines with AGREE-II to select three mother guidelines. Key clinical questions were formulated covering each step of the asthma management. RESULTS: The selected mother guidelines are British Thoracic Society (BTS), GINA and GEMA 2015. Responses to the questions were formulated according to the evidence in the mother guidelines. Recommendations or suggestions were made for asthma treatment in Mexico by the core group, and adjusted during several rounds of a Delphi process, taking into account: 1. Evidence; 2. Safety; 3. Cost; 4. Patient preference - all these set against the background of the local reality. Here the detailed analysis of the evidence present in BTS/GINA/GEMA sections on prevention and diagnosis in paediatric asthma are presented for three age-groups: children with asthma ≤5 years, 6-11 years and ≥12 years. CONCLUSIONS: For the prevention and diagnosis sections, applying the AGREE-II method is useful to develop a scientifically-sustained document, adjusted to the local reality per country, as is the Mexican Guideline on Asthma.


Assuntos
Asma/diagnóstico , Asma/prevenção & controle , Criança , Pré-Escolar , Feminino , Humanos , Masculino , México
8.
Acta Ortop Mex ; 32(6): 329-333, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-31184003

RESUMO

INTRODUCTION: In Mexico, the first meniscus transplant was performed in 2002. The objective was to describe the clinical evolution of patients with pain associated with postmenisectomy syndrome, who underwent meniscal allograft transplantation (MAT), with bony blocks via arthroscopy, with follow-up to one year. MATERIAL AND METHODS: A retrospective cohort study with a one-year follow-up was conducted. We included patients with joint interlining pain secondary to partial or total menisectomy, between 15 and 55 years of age, of both sexes, who underwent MAT. The clinical evolution was evaluated with visual analogue scale (VAS), SF-36 and Lysholm scale; the results are described in frequencies, percentages and p value was significant at 0.05. RESULTS: We included nine patients; eight men and one woman with an age of 31.3 years (16-52), the follow-up was 16.6 months (12-23). The preoperative VAS was 8.5 (6-10) and, at one year of follow-up, the average of this scale was 1.25 (0-5) (p 0.001). In the follow-up one year after the MAT, the Lysholm scale was on average 91 (68-100) and the SF-36 was on average 79.17 (65-92.92); three patients returned to their sports practice prior to the injury. CONCLUSION: This is the first report in Mexico that describes the one year follow-up of the MAT; significant clinical improvement was demonstrated (p 0.001) with remission of pain in the knee with previous menisectomy and in some cases the return to sports practice.


INTRODUCCIÓN: En México se realizó el primer trasplante de menisco en 2002. El objetivo fue describir la evolución clínica de pacientes con dolor asociado al síndrome postmeniscectomía que fueron sometidos a trasplante de menisco alogénico (MAT), con bloques óseos vía artroscópica con seguimiento a un año. MATERIAL Y MÉTODOS: Se realizó un estudio de cohorte retrospectiva con seguimiento a un año; se incluyeron pacientes con dolor en interlínea articular secundario a meniscectomía parcial o total, entre 15 y 55 años de edad, de ambos sexos, que fueron sometidos a MAT. La evolución clínica se evaluó con EVA, SF-36 y escala de Lysholm; los resultados se describen en frecuencias, porcentajes y valor de p significativa 0.05. RESULTADOS: Se incluyeron nueve pacientes; ocho hombres y una mujer con edad de 31.3 años (16-52), el seguimiento fue de 16.6 meses (12-23). La EVA prequirúrgica fue de 8.5 (6-10) y al año de seguimiento el promedio de esta escala fue de 1.25 (0-5) (p 0.001). En el seguimiento a un año posterior al MAT, la escala de Lysholm fue en promedio de 91 (68-100) y la SF-36 fue en promedio de 79.17 (65-92.92); tres pacientes regresaron a su práctica deportiva previa a la lesión. CONCLUSIÓN: Éste es el primer reporte en México del seguimiento a un año del MAT; se demostró mejoría clínica significativa (p 0.001) con remisión del dolor en la rodilla con meniscectomía previa y en algunos casos el retorno a la práctica deportiva.


Assuntos
Meniscos Tibiais , Lesões do Menisco Tibial , Adolescente , Adulto , Artroscopia , Feminino , Seguimentos , Humanos , Masculino , Meniscos Tibiais/transplante , México , Pessoa de Meia-Idade , Estudos Retrospectivos , Lesões do Menisco Tibial/terapia , Resultado do Tratamento , Adulto Jovem
9.
Rev. mex. ing. bioméd ; 37(3): 235-249, Sep.-Dec. 2016. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-961326

RESUMO

Resumen El presente artículo es una amplia revisión bibliográfica de algunos de los polímeros naturales más utilizados en la fabricación de apósitos para curación de heridas cutáneas y regeneración de piel en los últimos años. Asimismo, se presenta un análisis descriptivo de los polímeros de origen natural más estudiados en la ingeniería de tejidos, remarcando sus propiedades físicas, químicas y biológicas. Encontrando que las investigaciones más recientes se han centrado en la exploración de apósitos a partir de biopolímeros como una alternativa a los materiales sintéticos derivados del petróleo, debido a las propiedades que poseen, como una mayor biodegradabilidad, biocompatibilidad y sostenibilidad por ser obtenidos naturalmente. Sin embargo, aún no existe un apósito ideal que pueda ser aplicado de manera eficiente en todos los tipos de heridas; por lo que los investigadores se han enfocado en el desarrollo y la optimización de apósitos que satisfagan la mayoría de las necesidades para una etapa en particular de la herida.


Abstract This review includes the bio-polymers most used in recent years for the manufacturing of materials used as dressings in cutaneous wound healing and skin regeneration. Also, the natural polymers most studied in tissue engineering are mentioned, highlighting their physical, chemical and biological properties for skin regeneration and wound healing. Through an extensive review of the clinical and research uses different types of natural polymers were compared, as well as the results of chemical and biological tests carried out during experimental research performed internationally.

10.
Fish Physiol Biochem ; 42(2): 517-28, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26573856

RESUMO

Aquaculture in Mexico has been developed by the cultivation of commercial species. In Tabasco, the cultivation of native species is mainly limited by the lack of nutrition studies to support its crop profitability. Among these species is the tropical gar (Atractosteus tropicus), which has great potential for cultivation. However, the nutritional value of carbohydrates in diets for this species which contribute to improved growth and survival, have not been evalulated,. Thus, in the present investigation, isoprotein and isolipid diets have been designed based on the substitution of cellulose by corn starch (D1: 0% starch-15% cellulose, D2: 7.5% starch-7.5% cellulose and D3: 15% starch-0% cellulose) and compared with a commercial trout diet (45% protein and 16% lipids). A total of 1800 larvae (0.008 ± 0.002 g and 10.5 ± LT 0.126 mm) were used, distributed in a recirculation system in order to evaluate growth and survival for 30 days. The results show higher growth and survival of 97% of larvae fed the D3 diet, while cannibalism in the species was mitigated. Major digestive enzyme activities occurred (acid protease, alkaline protease, trypsin, chymotrypsin, leucine aminopeptidase, carboxypeptidase A, lipase, α-glucosidase and amylase) for larvae fed D3. It is concluded that the contribution of corn starch (15%) replacing cellulose in the diet improves growth and survival of this species.


Assuntos
Aquicultura , Dieta/métodos , Peixes/fisiologia , Amido , Amilases/metabolismo , Animais , Leucil Aminopeptidase/metabolismo , México , Peptídeo Hidrolases/metabolismo , Tripsina/metabolismo
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