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1.
Curr Issues Mol Biol ; 46(6): 5909-5928, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38921024

RESUMEN

Uropathogenic Escherichia coli (UPEC) is the main cause of urinary tract infections (UTIs) and carries virulence and resistance factors often found in mobilizable genetic elements, such as plasmids or pathogenicity islands (PAIs). UPEC is part of the extraintestinal pathogenic E. coli (ExPEC), but hybrid strains possessing both diarrheagenic E. coli (DEC) and ExPEC traits, termed "hypervirulent", present a significant health threat. This study assessed the prevalence of UPEC PAIs, ExPEC sequence types (ST), DEC genes, carbapenemase and extended-spectrum ß-lactamase (ESBL) phenotypes, resistance genotypes, and plasmids in 40 clinical isolates of UPEC. Results showed that 72.5% of isolates had PAIs, mainly PAI IV536 (53%). ESBL phenotypes were found in 65% of ß-lactam-resistant isolates, with 100% of carbapenem-resistant isolates producing carbapenemase. The predominant ESBL gene was blaCTX-M-2 (60%), and the most common resistance gene in fluoroquinolone and aminoglycoside-resistant isolates was aac(6')Ib (93%). Plasmids were present in 57% of isolates, and 70% belonged to the ST131 clonal group. Molecular markers for DEC pathotypes were detected in 20 isolates, with 60% classified as hybrid pathotypes. These findings indicate significant pathogenic potential and the presence of hybrid pathotypes in E. coli UTI clinical isolates in the Mexican population.

2.
Molecules ; 29(7)2024 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-38611939

RESUMEN

Biosynthesized silver nanoparticles (AgNPs) are widely used in varied applications, which are morphology dependent. Consequently, a morphology-controlled synthesis is mandatory. Although there are several studies focused on the plant extract-based biosynthesis of metallic nanoparticles, the use of extracts obtained from agro-wastes is scant. Furthermore, information regarding morphology modification through the use of additional agents is even more scarce. Thus, in this study, AgNPs were synthesized using a malt extract (ME) obtained from an artisanal beer brewing process residue. Additionally, sodium chloride (NaCl), gum arabic (GA), and talc (T) were used in an attempt to modify the morphology of AgNPs. XRD, DLS, SEM, and TEM results demonstrate that stable AgNPs of different sizes and shapes were synthesized. FTIR, HPLC analysis, and the quantification of total proteins, free amino acids, reducing sugars, and total polyphenols before and after AgNPs synthesis showed that ME biomolecules allowed them to act as a source of reducing and stabilizing agents. Therefore, this study provides evidence that ME can be successfully used to biosynthesize AgNPs. Additionally, the antibacterial activity of AgNPs against Gram-negative and Gram-positive bacteria was evaluated. Results indicate that AgNPs show a higher antibacterial activity against Gram-positive bacteria.


Asunto(s)
Acacia , Nanopartículas del Metal , Cerveza , Plata , Antibacterianos/farmacología , Cloruro de Sodio
3.
Sensors (Basel) ; 23(5)2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36904889

RESUMEN

Industrial robotic arms integrated with server computers, sensors and actuators have revolutionized the way automated non-destructive testing is performed in the aeronautical sector. Currently, there are commercial, industrial robots that have the precision, speed and repetitiveness in their movements that make them suitable for use in numerous non-destructive testing inspections. Automatic ultrasonic inspection of complex geometry parts remains one of the most difficult challenges in the market. The closed configuration, i.e., restricted access to internal motion parameters, of these robotic arms makes it difficult for an adequate synchronism between the movement of the robot and the acquisition of the data. This is a serious problem in the inspection of aerospace components, where high-quality images are necessary to assess the condition of the inspected component. In this paper, we applied a methodology recently patented for the generation of high-quality ultrasonic images of complex geometry pieces using industrial robots. The methodology is based on the calculation of a synchronism map after a calibration experiment and to introduce this corrected map in an autonomous, independent external system developed by the authors to obtain precise ultrasonic images. Therefore, it has been shown that it is possible to establish the synchronization of any industrial robot with any ultrasonic imaging generation system to generate high-quality ultrasonic images.

4.
Sensors (Basel) ; 22(17)2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36081108

RESUMEN

A new versatile and geometrically reconfigurable ultrasonic tomography system (UTS) has been designed to inspect and obtain information about the internal structure and inner damage of columns in heritage buildings. This nondestructive system is considered innovative because it aims to overcome common limitations of existing systems. Tomographic inspections are typically carried out manually and are thus limited to small portions of construction elements. The proposed UTS allows the automatization of the inspection and the generation of numerous tomographic slices along the height of the column. It is valid for multiple types of columns and materials. In the present work, the system was tested on two limestone columns of the north façade of the Convent of Carmo in Lisbon, Portugal. The UTS is composed of a mechanical and an electronic system. The mechanical system consists of four linear motion subsystems mounted in a square setup. A transducer is placed on each of the axes, acting as emitter or receiver of the ultrasonic signals. The mechanical system also includes a guide system to adapt the inspections to the complex geometry of the columns. The electronic system allows the control and the synchronization of the movements and the emission/reception configuration of the four ultrasonic transducers.


Asunto(s)
Transductores , Ultrasonido , Movimiento (Física) , Portugal , Ultrasonografía/métodos
5.
Evol Anthropol ; 30(2): 113-121, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33788352

RESUMEN

The relationship history of evolutionary anthropology and genetics is complex. At best, genetics is a beautifully integrative part of the discipline. Yet this integration has also been fraught, with punctuated, disruptive challenges to dogma, periodic reluctance by some members of the field to embrace results from analyses of genetic data, and occasional over-assertions of genetic definitiveness by geneticists. At worst, evolutionary genetics has been a tool for reinforcing racism and colonialism. While a number of genetics/genomics papers have disproportionately impacted evolutionary anthropology, here we highlight the 2002 presentation of an elegantly powerful approach for identifying "signatures" of past positive selection from haplotype-based patterns of genetic variation. Together with technological advances in genotyping methods, this article transformed our field by facilitating genome-wide "scans" for signatures of past positive selection in human populations. This approach helped researchers test longstanding evolutionary anthropology hypotheses while simultaneously providing opportunities to develop entirely new ones. Genome-wide scans for signatures of positive selection have since been conducted in diverse worldwide populations, with striking findings of local adaptation and convergent evolution. Yet there are ethical considerations with respect to the ubiquity of these studies and the cross-application of the genome-wide scan approach to existing datasets, which we also discuss.


Asunto(s)
Antropología Física/ética , Genética de Población/ética , Genoma Humano/genética , Selección Genética/genética , Adaptación Biológica/genética , Antropología Física/organización & administración , Evolución Molecular , Haplotipos/genética , Humanos , Metagenómica/ética , Publicaciones/estadística & datos numéricos
6.
BMC Nephrol ; 22(1): 99, 2021 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-33740896

RESUMEN

BACKGROUND: Access to kidney transplantation is limited to more than half of the Mexican population. A fragmented health system, gender, and sociocultural factors are barriers to transplant care. We analyzed kidney transplantation in Mexico and describe how public policies and sociocultural factors result in these inequities. METHODS: Kidney transplant data between 2007 to 2019 were obtained from the National Transplant Center database. Transplant rates and time spent on the waiting list, by age, gender, health system, and insurance status, were estimated. RESULTS: During the study period 34,931 transplants were performed. Recipients median age was 29 (IQR 22-42) years, 62.4% were males, and 73.9% were insured. 72.7% transplants were from living-donors. Annual transplant rates increased from 18.9 per million population (pmp) to 23.3 pmp. However, the transplant rate among the uninsured population remained low, at 9.3 transplants pmp. In 2019, 15,890 patients were in the waiting list; 60.6% were males and 88% were insured. Waiting time to transplant was 1.55 (IQR 0.56-3.14) years and it was shorter for patients listed in the Ministry of Health and private facilities, where wait lists are smaller, and for males. Deceased-organ donation rates increased modestly from 2.5 pmp to 3.9 pmp. CONCLUSIONS: In conclusion, access to kidney transplantation in Mexico is unequal and restricted to patients with medical insurance. An inefficient organ procurement program results in low rates of deceased-donor kidneys. The implementation of a comprehensive kidney care program, recognizing kidney transplantation as the therapy of choice for renal failure, offers an opportunity to correct these inequalities.


Asunto(s)
Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Disparidades en Atención de Salud/estadística & datos numéricos , Trasplante de Riñón/estadística & datos numéricos , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Masculino , México , Persona de Mediana Edad , Factores de Tiempo , Adulto Joven
7.
PLoS Genet ; 14(5): e1007382, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29768402

RESUMEN

Condensin complexes are key determinants of higher-order chromatin structure and are required for mitotic and meiotic chromosome compaction and segregation. We identified a new role for condensin in the maintenance of sister chromatid cohesion during C. elegans meiosis. Using conventional and stimulated emission depletion (STED) microscopy we show that levels of chromosomally-bound cohesin were significantly reduced in dpy-28 mutants, which lack a subunit of condensin I. SYP-1, a component of the synaptonemal complex central region, was also diminished, but no decrease in the axial element protein HTP-3 was observed. Surprisingly, the two key meiotic cohesin complexes of C. elegans were both depleted from meiotic chromosomes following the loss of condensin I, and disrupting condensin I in cohesin mutants increased the frequency of detached sister chromatids. During mitosis and meiosis in many organisms, establishment of cohesion is antagonized by cohesin removal by Wapl, and we found that condensin I binds to C. elegans WAPL-1 and counteracts WAPL-1-dependent cohesin removal. Our data suggest that condensin I opposes WAPL-1 to promote stable binding of cohesin to meiotic chromosomes, thereby ensuring linkages between sister chromatids in early meiosis.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Proteínas de Unión al ADN/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Meiosis/genética , Complejos Multiproteicos/metabolismo , Proteínas Nucleares/metabolismo , Adenosina Trifosfatasas/genética , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Ciclo Celular/genética , Cromátides/genética , Cromátides/metabolismo , Proteínas Cromosómicas no Histona/genética , Segregación Cromosómica/genética , Proteínas de Unión al ADN/genética , Hibridación Fluorescente in Situ , Péptidos y Proteínas de Señalización Intercelular/genética , Complejos Multiproteicos/genética , Mutación , Proteínas Nucleares/genética , Interferencia de ARN , Complejo Sinaptonémico/genética , Complejo Sinaptonémico/metabolismo , Cohesinas
8.
Sensors (Basel) ; 21(14)2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34300528

RESUMEN

This work studies ultrasonic propagation in liquid and ice water drops. The effect of porosity on attenuation of ultrasonic waves in the drops is also explored. The motivation of this research was the possible application of ultrasonic techniques to the study of interstellar and cometary ice analogs. These ice analogs, made by vapor deposition onto a cold substrate at 10 K, can display high porosity values up to 40%. We found that the ultrasonic pulse was fully attenuated in such ice, and decided to grow ice samples by freezing a liquid drop. Several experiments were performed using liquid or frozen water drops with and without pores. An ultrasonic pulse was transmitted through each drop and measured. This method served to estimate the ultrasonic velocity of each drop by measuring drop size and time-of-flight of ultrasonic transmission. Propagation of ultrasonic waves in these drops was also simulated numerically using the SimNDT program developed by the authors. After that, the ultrasonic velocity was related with the porosity using a micromechanical model. It was found that a low value of porosity in the ice is sufficient to attenuate the ultrasonic propagation. This explains the observed lack of transmission in porous astrophysical ice analogs.

9.
Am J Nephrol ; 49(5): 386-396, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30982046

RESUMEN

BACKGROUND: Chronic kidney disease (CKD) is a global public health problem and is linked to adverse outcomes during pregnancy; the high prevalence of CKD (3-6%) in women of childbearing age is of particular relevance in emerging countries where CKD prevalence is higher and resources are limited. Although CKD is a public health problem in Mexico, there is scant information on outcomes in pregnant CKD women in this country. We report maternal-fetal outcomes in a prospective cohort of poor, CKD pregnant women, and compare results with those of pregnant women without CKD. METHODS: A prospective study of pregnant CKD women referred to a public obstetrics/nephrology clinic from July 2013 to December 2017; sociodemographic and clinical data, including complications and perinatal outcomes, were recorded. CKD was defined at referral as per KDIGO guidelines; preeclampsia and superimposed preeclampsia were defined as appearance or worsening of hypertension and proteinuria. Findings were compared to official data for -Mexico and to a historic control of pregnant women without CKD who delivered at our hospital. RESULTS: Sixty-two pregnancies in CKD patients, age 23.4 ± 5.8 years were observed; 46.8% of patients were primiparous. At referral, serum creatinine was 1.8 (1.1-3.0) mg/dL with an estimate glomerular filtration rate (eGFR) of 38.1 (21.9-68.0) mL/min/1.73 m2. In half of the cases, CKD was diagnosed during pregnancy. Forty-eight pregnant women without CKD, age 27 (22-34) years, who delivered during the study period were selected as controls: 33% were primiparous, serum creatinine was 0.50 (0.4-0.6) mg/dL, and estimate glomerular filtration rate was 135 (112-174) mL/min/1.73 m2. Twenty patients needed dialysis (HD-CKD): 2 were already on dialysis, and 18 began treatment during pregnancy; 42 CKD patients did not require dialysis (non-HD CKD). After delivery, 15 patients remained dialysis dependent while 5 did not. Preeclampsia was more frequent in CKD patients in comparison to controls. In total, 93% of CKD patients and 98% of controls delivered a live baby. Prematurity was more frequent in CKD patients than controls and was higher in HD-CKD than in non-HD CKD. Birth weight was lower in CKD when compared to controls. Logistic regression showed a higher risk of preeclampsia in CKD pregnancies than in controls, but it was not affected by age, parity, CKD stage, or need for dialysis during pregnancy. CONCLUSIONS: Underserved CKD Mexican women have a high rate of adverse maternal-fetal outcomes during pregnancy. The risk may be higher in patients needing dialysis during pregnancy, many of whom remained dialysis dependent after delivery.


Asunto(s)
Nacimiento Vivo , Complicaciones del Embarazo/terapia , Insuficiencia Renal Crónica/terapia , Poblaciones Vulnerables/estadística & datos numéricos , Adolescente , Adulto , Estudios de Casos y Controles , Creatinina/sangre , Femenino , Tasa de Filtración Glomerular/fisiología , Humanos , México , Embarazo , Complicaciones del Embarazo/sangre , Complicaciones del Embarazo/fisiopatología , Estudios Prospectivos , Diálisis Renal/estadística & datos numéricos , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/fisiopatología , Medición de Riesgo , Factores de Riesgo , Factores Socioeconómicos , Adulto Joven
10.
Sensors (Basel) ; 19(21)2019 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-31717817

RESUMEN

In this paper, a magnetic microwire-based sensor array embedded under the pavement is proposed as a weighing system at customs ports of entry. This sensor is made of a cementitious material suitable for embedding within the core of concrete structures prior to curing. The objective of this research is to verify the feasibility of stress monitoring for concrete materials using an array of cement-based stress/strain sensors that have been developed using the magnetic sensing property of an embedded microwire in a cement-based composite. Test results for microwire-based sensors and gauge sensors are compared. The strain sensitivity and their linearity are investigated through experimental testing under compressive loadings. Sensors made of these materials can be designed to satisfy specific needs and reduce costs in the production of sensor aggregates with improved coupling performance, thus avoiding any disturbance to the stress state.

11.
Mol Phylogenet Evol ; 127: 878-890, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29958983

RESUMEN

Pollinator-mediated selection is a major driver of evolution in flowering plants, contributing to the vast diversity of floral features. Despite long-standing interest in floral variation and the evolution of pollination syndromes in Polemoniaceae, the evolution of floral traits and known pollinators has not been investigated in an explicit phylogenetic context. Here we explore macroevolutionary patterns of both pollinator specificity and three floral traits long considered important determinants of pollinator attraction across the most comprehensive species-level phylogenetic tree yet produced for the family. The presence of floral chlorophyll is reconstructed as the ancestral character state of the family, even though the presence of floral anthocyanins is the most prevalent floral pigment in extant taxa. Mean corolla length and width of the opening of the floral tube are correlated, and both appear to vary with pollinator type. The evolution of pollination systems appears labile, with multiple gains and losses of selfing and conflicting implications for patterns of diversification. Explicit testing of diversification models rejects the hypothesis that selfing is an evolutionary dead-end. This study begins to disentangle the individual components that comprise pollination syndromes and lays the foundation for future work on the genetic mechanisms that control each trait.


Asunto(s)
Biodiversidad , Evolución Biológica , Flores/fisiología , Animales , Extinción Biológica , Flores/genética , Análisis de los Mínimos Cuadrados , Fenotipo , Filogenia , Polinización , Análisis de Componente Principal , Carácter Cuantitativo Heredable , Reproducción/fisiología , Procesos Estocásticos , Factores de Tiempo
12.
Ann Clin Microbiol Antimicrob ; 17(1): 42, 2018 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-30526606

RESUMEN

BACKGROUND: The widespread Escherichia coli clone ST131 implicated in multidrug-resistant infections has been recently reported, the majority belonging to O25:H4 serotype and classified into five main virotypes in accordance with the virulence genes carried. METHODS: Pathogenicity Islands I and II (PAI-I and PAI-II) were determined using conventional PCR protocols from a set of four E. coli CTXR ST131 O25:H4/H30-Rx strains collected from healthy donors' stool. The virulence genes patterns were also analyzed and compared them with the virotypes reported previously; then adherence, invasion, macrophage survival and biofilm formation assays were evaluated and AIEC pathotype genetic determinants were investigated. FINDINGS: Non-reported virulence patterns were found in our isolates, two of them carried satA, papA, papGII genes and the two-remaining isolates carried cnfI, iroN, satA, papA, papGII genes, and none of them belonged to classical ST131 virotypes, suggesting an endemic distribution of virulence genes and two new virotypes. The presence of PAI-I and PAI-II of Uropathogenic E. coli was determined in three of the four strains, furthermore adherence and invasion assays demonstrated higher degrees of attachment/invasion compared with the control strains. We also amplified intI1, insA and insB genes in all four samples. INTERPRETATION: The results indicate that these strains own non-reported virotypes suggesting endemic distribution of virulence genes, our four strains also belong to an AIEC pathotype, being this the first report of AIEC in México and the association of AIEC with healthy donors.


Asunto(s)
Adhesión Bacteriana , Escherichia coli Uropatógena/fisiología , Escherichia coli Uropatógena/patogenicidad , Enfermedades Asintomáticas , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Heces/microbiología , Humanos , Serogrupo , Escherichia coli Uropatógena/genética , Escherichia coli Uropatógena/aislamiento & purificación , Virulencia
13.
Clin Nephrol ; 90(5): 350-356, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30021693

RESUMEN

BACKGROUND: Clostridium difficile infection (CDI) is a leading cause of healthcare-associated diarrhea worldwide. Patients with chronic kidney disease (CKD) are especially vulnerable, as they are exposed to CDI risk factors including frequent antibiotics. MATERIALS AND METHODS: In order to identify the risk factors for CDI in CKD patients, a 33-month long case-control study was carried out at a tertiary-care hospital in Mexico. CDI was confirmed at the genetic level, and univariate and multivariate analyses were performed to identify the association between risk factors, biomarkers, and outcome options (survival, relapse, death). RESULTS: Among the 1,198 patients with healthcare-associated diarrhea, 354 (29.5%) were CDI cases. 105 (29.6%) CDI cases and 192 (22.7%) controls had CKD. 84 (80%) CKD+CDI cases had a favorable outcome, 10 (9.5%) relapsed, and the 3-month mortality rate included 11 (10.4%) patients. Compared with controls, CDI cases had more previous hospitalizations (63.8 vs. 46.9%, p = 0.005), abdominal distension (46.7 vs. 36.5%, p = 0.056), abdominal pain (60.0 vs. 41.1%, p = 0.002), and polymorphonuclear leukocyte in stools (71.4 vs. 40.5%, p = 0.001) as well as poorer outcomes at 3 months. The patients in the 027-strain group were older, and most of the patients had CKD stage 5 (88.5% vs. 71.1%, p = 0.007), while CKD stage-4 patients were more frequently infected with non-027 strains. In the multivariate analysis of risk factors for CDI, only previous antibiotic exposure (odds ratio = 2.01, 95% confidence interval: 1.05 - 3.84; p = 0.034) was independently associated with CDI in patients with CKD stage 5. CONCLUSION: Mexican patients with CKD are at risk for CDI. This susceptible group should be protected by promoting appropriate guidelines.
.


Asunto(s)
Clostridioides difficile , Infecciones por Clostridium/complicaciones , Infecciones por Clostridium/epidemiología , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/epidemiología , Humanos , México/epidemiología , Factores de Riesgo
14.
Sensors (Basel) ; 17(5)2017 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-28489062

RESUMEN

This study explores the feasibility of using transmission tomographic images based on attenuation measures in transmission to detect and estimate the most common materials that are embedded in concrete, reinforcements and natural and artificial voids. A limited set of concrete specimens have been made in which cylindrical objects such as bars/tubes of steel, PVC and aluminium have been embedded to analyse the effect of size and material. The methodology and scope of this study is presented and numerical simulations are carried out to optimize the emitter-receiver configuration and to understand the complex physical propagation phenomena of ultrasonic signals that travel through concrete with embedded inclusions. Experimental tomographic images are obtained by using an ultrasonic tomographic system, which has the advantage of needing only two ultrasonic transducers. Both the software simulation tool and the tomographic inspection system are developed by the authors. The obtained results show that PVC tubes and steel bars of diameters higher than 19 mm and embedded in cylindrical specimens, can be detected and their sizes estimated using segmented tomographic images.

15.
Int J Mol Sci ; 18(5)2017 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-28475151

RESUMEN

Natural extracts possess several kinds of antioxidants (anthocyanins, betalains, thymol, carvacrol, and resveratrol) that have also demonstrated antimicrobial properties. In order to study these properties, extracts from cranberry, blueberry, beetroot, pomegranate, oregano, pitaya, and resveratrol (from grapes) were obtained. Growth inhibition tests of mesophilic aerobes, coliforms, and fungi were conducted in films prepared from the extracts in accordance with Mexican Official Norms (NOM). Optical properties such as transparency and opacity, mechanical properties, and pH were also analyzed in these materials. The films with beetroot, cranberry, and blueberry extracts demonstrated the best antimicrobial activity against various bacteria and fungi in comparison with unmodified chitosan-starch film. This study shows that the addition of antioxidants improved the antimicrobial performance of these films. It was also found that antimicrobial properties are inherent to the films. These polymers combined with the extracts effectively inhibit or reduce microorganism growth from human and environmental contact; therefore, previous sterilization could be unnecessary in comparison with traditional plastics. The presence of extracts decreased transmittance percentages at 280 and 400 nm, as well as the transparency values, while increasing their opacity values, providing better UV-VIS light barrier properties. Despite diminished glass transition temperatures (Tg), the values obtained are still adequate for food packaging applications.


Asunto(s)
Antiinfecciosos/farmacología , Quitosano/química , Frutas/química , Extractos Vegetales/farmacología , Almidón/química , Antiinfecciosos/síntesis química , Antiinfecciosos/química , Aspergillus/efectos de los fármacos , Enterobacteriaceae/efectos de los fármacos , Fenómenos Mecánicos , Fenómenos Ópticos , Penicillium/efectos de los fármacos , Extractos Vegetales/química
16.
Biol Res ; 48: 17, 2015 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-25889629

RESUMEN

BACKGROUND: Karwinskia humboldtiana (Kh) is a poisonous plant of the rhamnacea family. To elucidate some of the subcellular effects of Kh toxicity, membrane fluidity and ATPase activities as hydrolytic and as proton-pumping activity were assessed in rat liver submitochondrial particles. Rats were randomly assigned into control non-treated group and groups that received 1, 1.5 and 2 g/Kg body weight of dry powder of Kh fruit, respectively. Rats were euthanized at day 1 and 7 after treatment. RESULTS: Rats under Kh treatment at all dose levels tested, does not developed any neurologic symptoms. However, we detected alterations in membrane fluidity and ATPase activity. Lower dose of Kh on day 1 after treatment induced higher mitochondrial membrane fluidity than control group. This change was strongly correlated with increased ATPase activity and pH gradient driven by ATP hydrolysis. On the other hand, membrane fluidity was hardly affected on day 7 after treatment with Kh. Surprisingly, the pH gradient driven by ATPase activity was significantly higher than controls despite an diminution of the hydrolytic activity of ATPase. CONCLUSIONS: The changes in ATPase activity and pH gradient driven by ATPase activity suggest an adaptive condition whereby the fluidity of the membrane is altered.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Karwinskia/toxicidad , Fluidez de la Membrana/efectos de los fármacos , Mitocondrias Hepáticas/efectos de los fármacos , Animales , Frutas/toxicidad , Masculino , Mitocondrias Hepáticas/enzimología , Fuerza Protón-Motriz/efectos de los fármacos , Distribución Aleatoria , Ratas Sprague-Dawley , Fracciones Subcelulares/efectos de los fármacos , Partículas Submitocóndricas/efectos de los fármacos
17.
Phys Chem Chem Phys ; 16(33): 17551-9, 2014 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-25025655

RESUMEN

This work reports on the formation of different types of structures on the surface of polymer films upon UV laser irradiation. Poly(ethylene terephthalate) was irradiated with nanosecond UV pulses at 193 and 266 nm. The polarization of the laser beam and the irradiation angle of incidence were varied, giving rise to laser induced surface structures with different shapes and periodicities. The irradiated surfaces were topographically characterized by atomic force microscopy and the chemical modifications induced by laser irradiation were inspected via micro-Raman and fluorescence spectroscopies. Contact angle measurements were performed with different liquids, and the results evaluated in terms of surface free energy components. Finally, in order to test the influence of surface properties for a potential application, the modified surfaces were used for mesenchymal stem cell culture assays and the effect of nanostructure and surface chemistry on cell adhesion was evaluated.


Asunto(s)
Adhesión Celular/fisiología , Rayos Láser , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/fisiología , Tereftalatos Polietilenos/química , Tereftalatos Polietilenos/efectos de la radiación , Rayos Ultravioleta , Adhesividad/efectos de la radiación , Células Cultivadas , Humanos , Ensayo de Materiales , Dosis de Radiación , Propiedades de Superficie/efectos de la radiación
18.
Nucleic Acids Res ; 40(Database issue): D1202-10, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22140109

RESUMEN

The Arabidopsis Information Resource (TAIR, http://arabidopsis.org) is a genome database for Arabidopsis thaliana, an important reference organism for many fundamental aspects of biology as well as basic and applied plant biology research. TAIR serves as a central access point for Arabidopsis data, annotates gene function and expression patterns using controlled vocabulary terms, and maintains and updates the A. thaliana genome assembly and annotation. TAIR also provides researchers with an extensive set of visualization and analysis tools. Recent developments include several new genome releases (TAIR8, TAIR9 and TAIR10) in which the A. thaliana assembly was updated, pseudogenes and transposon genes were re-annotated, and new data from proteomics and next generation transcriptome sequencing were incorporated into gene models and splice variants. Other highlights include progress on functional annotation of the genome and the release of several new tools including Textpresso for Arabidopsis which provides the capability to carry out full text searches on a large body of research literature.


Asunto(s)
Arabidopsis/genética , Bases de Datos Genéticas , Genes de Plantas , Anotación de Secuencia Molecular , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Genoma de Planta , Programas Informáticos
19.
Microbiol Resour Announc ; : e0011324, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38530041

RESUMEN

Herein is reported the draft genome sequence of a triple hybrid Escherichia coli strain isolated from a healthy donor feces. The assembly is 5.2 Mbp, composed of 247 contigs, with a N50 of 77, 241 bp, presenting a GC content of 50.8%.

20.
Microbiol Resour Announc ; 13(7): e0019224, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-38842343

RESUMEN

Uropathogenic Escherichia coli (UPEC) remains the main etiological agent of urinary tract infections affecting females and males. The draft genome sequence of three strains of UPEC isolated from senior citizens and pregnant women in the state of Puebla, Mexico, is reported here.

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