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1.
J Chem Ecol ; 48(7-8): 650-659, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35921017

RESUMEN

Parasitoids are known to exploit volatile cues emitted by plants after herbivore attack to locate their hosts. Feeding and oviposition of a polyphagous herbivore can induce the emission of odor blends that differ among distant plant species, and parasitoids have evolved an incredible ability to discriminate them and locate their hosts relying on olfactive cues. We evaluated the host searching behavior of the egg parasitoid Cosmocomoidea annulicornis (Ogloblin) (Hymenoptera: Mymaridae) in response to odors emitted by two taxonomically distant host plants, citrus and Johnson grass, after infestation by the sharpshooter Tapajosa rubromarginata (Signoret) (Hemiptera: Cicadellidae), vector of Citrus Variegated Chlorosis. Olfactory response of female parasitoids toward plants with no herbivore damage and plants with feeding damage, oviposition damage, and parasitized eggs was tested in a Y-tube olfactometer. In addition, volatiles released by the two host plant species constitutively and under herbivore attack were characterized. Females of C. annulicornis were able to detect and significantly preferred plants with host eggs, irrespectively of plant species. However, wasps were unable to discriminate between plants with healthy eggs and those with eggs previously parasitized by conspecifics. Analysis of plant volatiles induced after sharpshooter attack showed only two common volatiles between the two plant species, indole and ß-caryophyllene. Our results suggest that this parasitoid wasp uses common chemical cues released by many different plants after herbivory at long range and, once on the plant, other more specific chemical cues could trigger the final decision to oviposit.


Asunto(s)
Conducta de Búsqueda de Hospedador , Compuestos Orgánicos Volátiles , Avispas , Animales , Señales (Psicología) , Femenino , Interacciones Huésped-Parásitos , Larva/fisiología , Oviposición , Plantas , Compuestos Orgánicos Volátiles/análisis , Avispas/fisiología
2.
Sci Total Environ ; 845: 157286, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35835190

RESUMEN

Cultural eutrophication is the leading cause of water quality degradation worldwide. The traditional monitoring of eutrophication is time-consuming and not integrative in space and time. Here, we examined the use of carbon (δ13C) and nitrogen (δ15N) isotopic composition to track the degree of eutrophication in a bay of Lake Titicaca impacted by anthropogenic (urban, industrial and agricultural wastewater) discharges. Our results show increasing δ13C and decreasing δ15N signatures in macrophytes and suspended particulate matter with distance to the wastewater source. In contrast to δ15N and δ13C signatures, in-between aquatic plants distributed along the slope were not only affected by anthropogenic discharges but also by the pathway of carbon uptake, i.e., atmospheric (emerged) vs aquatic (submerged). A binary mixing model elaborated from pristine and anthropogenic isotope end-members allowed the assessment of anthropogenically derived C and N incorporation in macrophytes with distance to the source. Higher anthropogenic contribution was observed during the wet season, attributed to enhanced wastewater discharges and leaching of agricultural areas. For both seasons, eutrophication was however found naturally attenuated within 6 to 8 km from the wastewater source. Here, we confirm that carbon and nitrogen stable isotopes are simple, integrative and time-saving tools to evaluate the degree of eutrophication (seasonally or annually) in anthropogenically impacted aquatic ecosystems.


Asunto(s)
Lagos , Ríos , Bolivia , Carbono , Isótopos de Carbono , Ecosistema , Monitoreo del Ambiente/métodos , Eutrofización , Nitrógeno/análisis , Isótopos de Nitrógeno/análisis , Aguas Residuales
3.
Rev. ANACEM (Impresa) ; 16(2): 84-87, 2022. tab, ilus
Artículo en Español | LILACS | ID: biblio-1525872

RESUMEN

Introducción: La enfermedad de Alzheimer (EA) es la principal causa de demencia, caracterizada por pérdida progresiva de memoria. Principal fuente de morbimortalidad en mayores de 65 años. En los últimos 20 años las muertes por EA han aumentado un 145% en el mundo. En Chile no hay estudios actuales que describan mortalidad por EA. El objetivo del presente trabajo es analizar y comparar las tasas de mortalidad (TM) por EA según sexo y grupo etario en Chile entre 2017-2021. Materiales y métodos: Estudio descriptivo, ecológico, sobre defunciones por EA entre 2017-2021 en Chile según sexo y grupo etario (n=10.223). Información obtenida de la base de datos del Departamento de Estadísticas e Información de Salud. Se realizó estadística descriptiva y cálculo de TM. No se requiere comité de ética. Resultados: La máxima TM del periodo fue 11,74 por cada 100.000 habitantes en 2021. El sexo femenino logró la mayor TM en este periodo. El grupo etario con mayor cantidad de defunciones fue el de 81 o más años con 76.6% (7.829) de las defunciones totales. Discusión: Se evidenció mantención y luego ascenso de TM por EA, podría deberse al aumento en la esperanza de vida. La mayor frecuencia de defunciones según sexo y edad, podría explicarse por mayor vulnerabilidad femenina a desarrollar EA y a cambios fisiológicos del envejecimiento. En conclusión, la TM por EA en Chile ha aumentado, probablemente secundario al aumento en la esperanza de vida. Se hace un llamado a continuar el estudio de la patología.


Introduction: Alzheimer's disease (AD) is the most common cause of dementia, characterized by progressive memory loss. It is the main source of morbidity and mortality in individuals over 65 years of age, with age being its primary non-modifiable risk factor. In the last 20 years, deaths from AD have increased by 145% worldwide. However, there are no current studies in Chile that describe mortality from AD. The objective of this study is to analyze and compare mortality rates due to AD according to sex and age group in the Chilean population during the years 2017-2021. Material and Methods: Descriptive, ecological study on deaths from AD between 2017-2021 in Chile, categorized by sex and age group (n=10,223). The database was obtained from the Department of Health Statistics and Information. Descriptive statistics and mortality rate calculations were performed. No ethics committee approval was required. Results: The maximum mortality rate (MR) was observed in 2021 with a value of 11.74 per 100,000 inhabitants. Women had the highest MR in this period. The age group with the highest number of deaths was 81 years or older, accounting for 76.6% (7,829) of the total deaths. Discussion: A plateau and subsequent increase in MR due to AD were observed, possibly explained by the increase in life expectancy. The higher frequency of deaths in women and specific age groups may be attributed to the higher vulnerability of women to developing AD and physiological changes related to aging. In conclusion, the MR from AD has increased in Chile, likely due to the rise in life expectancy, emphasizing the importance of continued research on this pathology.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Adulto Joven , Enfermedad de Alzheimer/mortalidad , Enfermedad de Alzheimer/epidemiología , Chile/epidemiología , Epidemiología Descriptiva , Distribución por Edad y Sexo
4.
SAGE Open Med ; 9: 20503121211037471, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34394933

RESUMEN

INTRODUCTION: Higher prevalence of osteopenia and osteoporosis in HIV positive patients compared to non-infected population has been recognized. However, cancer patients have a higher risk of bone loss and fractures that is multifactorial. The aim of the study was to describe the prevalence of osteopenia and osteoporosis in HIV positive women with history of treated cancer. METHODS: Between January 2018 and December 2019, women aged >40 years, HIV+ with a history of cancer diagnosis, who attended the AIDS Cancer Clinic at Instituto Nacional de Cancerología, Mexico City, and who had a dual X-ray absorptiometry performed during the study period were included. Two control groups (CG)-HIV negative women with history of cancer (CG1) and non-HIV, non-cancer women (CG2)-were matched by age 1:1. RESULTS: Forty-eight patients in each group were included; the mean age was 51.1 ± 8.1 years. Osteopenia was found in femoral neck in 54.2% (HIV+), 37.5% (CG1), and 27.1% (CG2), p = 0.02; in spine was 35.7%, 47.9%, and 31.2%, respectively, p = 0.442. Osteoporosis in femoral neck was documented in 12.5%, 2.1%, and 0% in HIV+, CG1, and CG2 (p = 0.03), and in the spine was 47.9%, 16.7%, and 14.6%, respectively (p = 0.002). CONCLUSION: HIV patients with a history of treated cancer have a much higher prevalence of osteoporosis when compared with same-aged HIV-uninfected women with and without cancer. It is necessary to monitor Bone Mineral Density periodically, and all patients should be encouraged to make lifestyle changes, such as avoid tobacco and alcohol, and to increase exercising.

5.
Int J Health Geogr ; 20(1): 26, 2021 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-34090437

RESUMEN

BACKGROUND: Independent mobility (IM) provides young people with many opportunities to increase their autonomy and physical activity (PA). This study aimed to analyse whether the parent's PA, active commuting to work and sociodemographic factors serve as predictors of IM to school in children and adolescents. METHODS: A total of 684 parents (52.8% mothers) and their offspring (56.4% girls) were included in this study, which was performed in Granada (Spain) and Valparaíso (Chile). The parents self-reported their sociodemographic characteristics, PA and mode of commuting to work. The mode of commuting to and from school and the offspring accompaniment mode were reported. T-test and chi-square test were used to study quantitative and qualitative differences by parental gender, respectively. Binary logistic regression models (odds ratio = OR) and stepwise analysis were performed to study the association between the parents' sociodemographic variables and IM to school. RESULTS: Adolescents showed higher IM to school than children (58.9% vs 40.2%; p < 0.001). No car availability and shorter distance to work were positively associated with higher IM to school in children (OR = 2.22 and 2.29, respectively). Mothers' lower salary/month (OR = 2.75), no car availability (OR = 3.17), and mother passive commuting to work (OR = 2.61) were positively associated with higher IM to school in adolescents. The main predictor of IM to school in children and adolescents was no car availability (OR = 6.53). CONCLUSION: Parental sociodemographic factors, such as salary, distance to work and car availability, were associated more strongly with IM than parental PA and active commuting to work.


Asunto(s)
Transportes , Caminata , Adolescente , Ciclismo , Niño , Chile , Estudios Transversales , Ejercicio Físico , Femenino , Humanos , Masculino , Padres , Instituciones Académicas , España/epidemiología , Encuestas y Cuestionarios
6.
Int J STD AIDS ; 31(11): 1110-1113, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32753005

RESUMEN

We present the case of a 28-year-old man with recently-diagnosed human immunodeficiency virus and hepatitis C virus infection. He developed obstructive cholangiopathy secondary to cytomegalovirus and Kaposi sarcoma, both diagnosed by endoscopic retrograde cholangiopancreatography and biopsies. He received antiretroviral therapy, chemotherapy and valganciclovir with full recovery.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Terapia Antirretroviral Altamente Activa/métodos , Enfermedades de los Conductos Biliares/etiología , Infecciones por VIH/tratamiento farmacológico , Valganciclovir/uso terapéutico , Dolor Abdominal/etiología , Adulto , Enfermedades de los Conductos Biliares/diagnóstico , Biopsia , Colangiopancreatografia Retrógrada Endoscópica , Citomegalovirus , Diarrea , Fiebre/etiología , Infecciones por VIH/diagnóstico , Hepatitis C/complicaciones , Humanos , Masculino , Sarcoma de Kaposi , Pérdida de Peso
7.
Rev. MVZ Córdoba ; 25(2): 96-100, mayo-ago. 2020. tab
Artículo en Español | LILACS | ID: biblio-1340778

RESUMEN

RESUMEN Objetivo. Se pretende determinar la prevalencia, la diversidad y la resistencia antimicrobiana de las cuatro especies zoonóticas de Arcobacter en cerdos sanos, a nivel de matadero. Materiales y métodos. Fueron recolectadas, mediante muestreo no probabilístico por conveniencia, 50 muestras fecales obtenidas por hisopado rectal de cerdos sanos a nivel de matadero, antes de su faenamiento. El aislamiento de las cepas de Arcobacter fue realizado por métodos microbiológicos, utilizando enriquecimiento selectivo en caldo y filtración pasiva, mientras que para la identificación de especie fueron utilizadas pruebas bioquímicas y moleculares (multiplex PCR). El comportamiento frente a los antimicrobianos fue determinado por el método de disco difusión. Resultados. Fueron aisladas las cuatro especies zoonóticas, las cuales presentaron las siguientes frecuencias de aislamiento: A. thereius (18.0%), A. skirrowii (18.0%), A. cryaerophilus (6.0%) y A. butzleri (2.0%). Se encontró alta frecuencia de resistencia a ciprofloxacina y en las cuatro especies fueron aisladas cepas multirresistentes (resistentes a más de tres antibióticos).


ABSTRACT Objective. To establish the prevalence, diversity and antimicrobial resistance of the zoonotic species of Arcobacter in healthy pigs at slaughterhouse level. Material and methods. Fifty fecal samples were taken by rectal swabs from healthy pigs, before the beginning of the slaughter at the slaughterhouse of Loja city, Southern Ecuador. Sampling was done by means of a non-probabilistic method for convenience. Isolation of Arcobacter strains was done by microbiological methods and species identification using biochemical and molecular (multiplex PCR) tests. Antimicrobial behavior was performed using the disk diffusion method. Results. The four zoonotic species of Arcobacter were found. The isolation rates were A. thereius (18.0%), A. skirrowii (18.0%), A. cryaerophilus (6.0%) and A. butzleri (2.0%). High resistance to ciprofloxacin was found and multi-resistant strains were isolated from these four species. Conclusions. The fecal carriage of the zoonotic species of Arcobacter was demonstrated in pigs at slaughterhouse level. These species showed high resistance to ciprofloxacin being isolated muti-resistant strains among these four species.


Asunto(s)
Porcinos , Zoonosis , Reservorios de Agua , Epidemiología , Antibacterianos
8.
Arch Cardiol Mex ; 90(Supl): 33-35, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32523135

RESUMEN

The communications accumulated in the last weeks make it clear that there is no agreement to define the best treatment strategy in patients with acute coronary syndrome (SICA). In patients presenting with an acute myocardial infarction with ST-segment elevation (IAMCESST), it has been suggested to favor fibrinolysis (FL) over primary percutaneous coronary intervention (PCI), reserving ICP for cases of failed FL1,2; however, some societies have maintained the indication of the ICPp as the repercussion method of choice3. In SICAs without ST segment elevation (SICASESST) the recommendations are very similar, favoring medical treatment over percutaneous coronary intervention in this subgroup of patients1. Several companies consider the contagion status, particularly in the SICASESST, to decide which repercussion follow3. Anticipating that the epidemiological curve in Mexico will be similar to that observed in most countries, we recommend continuing the care of patients with SICA, the catheterization rooms must maintain their operation.


Las comunicaciones acumuladas en las últimas semanas dejan claro que no existe un acuerdo para definir la mejor estrategia de tratamiento en los pacientes con un síndrome coronario agudo (SICA). En los pacientes que se presentan con un infarto agudo del miocardio con elevación del segmento ST (IAMCESST) se ha sugerido privilegiar la fibrinólisis (FL) sobre la intervención coronaria percutánea primaria (ICPp), reservando el ICP para los casos de FL fallidar1,2; sin embargo algunas sociedades han mantenido la indicación de la ICPp como el método de repercusión de elecciónr3. En los SICA sin elevación del segmento ST (SICASESST) las recomendaciones son muy similares, favoreciendo el tratamiento medico sobre el intervencionismo coronario percutáneo, en este subgrupo de pacientes1. Varias sociedades consideran el estado de contagio, en particular en los SICASESST, para decidir que estrategia de repercusión seguir3. Anticipando que la curva epidemiológica en México será similar a la observada en la mayoría de los países, recomendamos continuar la atención de los pacientes con SICA, las salas de cateterismo deben mantener su funcionamiento.


Asunto(s)
Síndrome Coronario Agudo/terapia , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , Síndrome Coronario Agudo/fisiopatología , COVID-19 , Cateterismo Cardíaco , Infecciones por Coronavirus/prevención & control , Brotes de Enfermedades , Humanos , México/epidemiología , Infarto del Miocardio sin Elevación del ST/fisiopatología , Infarto del Miocardio sin Elevación del ST/terapia , Pandemias/prevención & control , Intervención Coronaria Percutánea/métodos , Neumonía Viral/prevención & control , Infarto del Miocardio con Elevación del ST/fisiopatología , Infarto del Miocardio con Elevación del ST/terapia
9.
Curr HIV Res ; 18(4): 277-282, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32493198

RESUMEN

BACKGROUND: Disseminated Kaposi sarcoma (DKS) is present in patients with advanced HIV infection in whom co-infection with other opportunistic pathogens can occur. Bone marrow (BM) aspirate and biopsy comprise a robust diagnostic tool in patients with fever, cytopenias, and abnormal liver tests. However, the yield in patients with DKS has not been determined. OBJECTIVE: The aim of this study was to evaluate the utility of BM aspirate and biopsy in patients with DKS. METHODS: We included 40 male patients with a recent diagnosis of DKS. BM aspirate and biopsy was performed as part of the workup to rule out co-infections. RESULTS: In four patients, Mycobacterium avium complex (MAC) was recovered from culture. In other four patients, intracellular yeasts were observed in the Grocott stain, diagnosed as Histoplasma. The yield of BM was calculated in 20%. Only 12 patients (30%) had fever and 11 (27.5%) had pancytopenia. Alkaline phosphatase (ALP) above normal values and C-reactive protein (CRP) were higher in patients with positive results for BM than in those with negative results (63% vs. 21.9%, and 3.0 vs. 1.2 mg/L; p = 0.03 in both comparisons). No differences were found when complete blood-count abnormalities were compared. CONCLUSION: We recommend performing a BM aspirate for stains, culture, and biopsy in all HIV patients with DKS, as this will permit the early diagnosis of co-infections and prevent further complications in those who receive chemotherapy.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Médula Ósea/microbiología , Infecciones por VIH/diagnóstico , Histoplasma/crecimiento & desarrollo , Histoplasmosis/diagnóstico , Sarcoma de Kaposi/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Infecciones Oportunistas Relacionadas con el SIDA/patología , Infecciones Oportunistas Relacionadas con el SIDA/virología , Adulto , Fosfatasa Alcalina/metabolismo , Biomarcadores/metabolismo , Biopsia , Cultivo de Sangre , Médula Ósea/metabolismo , Médula Ósea/cirugía , Médula Ósea/virología , Proteína C-Reactiva/metabolismo , VIH/crecimiento & desarrollo , VIH/patogenicidad , Infecciones por VIH/microbiología , Infecciones por VIH/patología , Infecciones por VIH/virología , Histoplasma/aislamiento & purificación , Histoplasma/patogenicidad , Histoplasmosis/microbiología , Histoplasmosis/patología , Histoplasmosis/virología , Humanos , Masculino , Persona de Mediana Edad , Sarcoma de Kaposi/microbiología , Sarcoma de Kaposi/patología , Sarcoma de Kaposi/virología
11.
Artículo en Inglés, Español | MEDLINE | ID: mdl-31987781

RESUMEN

OBJECTIVE: To determine the risk factors associated with prosthetic knee infection in elderly patients in a referral hospital in Peru. PATIENTS AND METHODS: A case and control study was performed. The calculated sample was 44 cases and 132 controls. The data were collected retrospectively from clinical records. U-Mann Whitney and Chi-square tests were performed in the comparison of cases and controls. Odds ratios (OR) were calculated in a binary logistic regression analysis to identify the risk factors, a P<.05 and a 95% confidence interval (CI) were considered significant. RESULTS: Significant (P<.05) risk factors evidenced in the bivariate analysis were obesity (OR=9.72; 95%CI: 4.47-21.14), smoking (OR=4.06; 95%CI: 1.59-10.39), rheumatoid arthritis (OR=4.66; 95%CI: 1.52-14.32), diabetes mellitus type2 (OR=5.63; 95%CI: 2.69-11.78), persistent drainage (OR=9.27; 95%CI: 3.85-22.31), superficial infection (OR=6.87; 95%CI: 3.25-14.49) and prolonged hospital stay (OR=4.67; 95%CI: 2.26-9.64). In the multivariate analysis where it was adjusted for confounding variables, it was determined that risk factors were obesity (ORa=9.14; 95%CI: 3.28-25.48), diabetes mellitus (ORa=3.77; 95%CI: 1.38-10.32), persistent drainage (ORa=4.64; 95%CI: 1.03-20.80) and superficial wound infection (ORa=27.35; 95%CI: 2.57-290.64). CONCLUSIONS: Risk factors for prosthetic knee infection identified in this study are preventable. The main risk factors were obesity, diabetes mellitus type2, superficial wound infection and persistent drainage, which were considered together or separately to be risk factors in the population studied.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/efectos adversos , Infecciones Relacionadas con Prótesis/etiología , Anciano , Anciano de 80 o más Años , Artritis Reumatoide/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Métodos Epidemiológicos , Femenino , Humanos , Tiempo de Internación , Masculino , Obesidad/complicaciones , Perú , Fumar/efectos adversos , Infección de la Herida Quirúrgica/complicaciones
12.
Mar Pollut Bull ; 150: 110701, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31796235

RESUMEN

Mangroves in the Northwest Coast of South America are contaminated with heavy metals due to wastewater discharges from industries, affecting the biota from this environment. However, bacteria proliferate in these harsh environmental conditions becoming possible sentinel of these contaminations. In this study, bacterial community composition was analyzed by throughput sequencing of the 16S rRNA gene from polluted and pristine mangrove sediments affected by marked differences in heavy metal concentrations. Core bacteria were dominated by Proteobacteria, Firmicutes, and Bacteroidetes phyla, with strong differences between sites at class and genus levels, correlated with metal levels. Increment of abundance on specific OTUs were associated with either elevated or decreased concentrations of metals and with the sulfur cycle. The abundance of Sulfurovum lithotrophicum, Leptolinea tardivitalis, Desulfococcus multivorans and Aminobacterium colombiense increases when metals rise. On contrary, Bacillus stamsii, Nioella nitrareducens and Clostridiisalibacter paucivorans abundance increases when metal levels are reduced. We propose these OTUs as bacterial sentinels, whose abundance can help monitor the restoration programs of contaminated mangrove sediments in the future.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos/microbiología , Metales Pesados , Contaminantes Químicos del Agua/análisis , Humedales , Bacterias , ARN Ribosómico 16S , América del Sur
13.
Bull Entomol Res ; 110(4): 438-448, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31813400

RESUMEN

The willow sawfly, Nematus oligospilus (Förster), is a pest in Salix commercial forests and has been reported worldwide. Female adults must recognize a suitable host plant to oviposit, since her offspring lack the ability to move to another host. We evaluated the effect of conspecific herbivory on the oviposition choices of N. oligospilus females by providing damaged (DP) and undamaged (UP) plants of Salix humboldtiana, a native willow from South America, as oviposition substrates. Local and systemic effects were studied. For the local treatment, a twig from the DP with damaged leaves was contrasted to a twig from a UP in dual choice experiments. For systemic treatment, a twig from the DP with intact leaves was contrasted to a twig from a UP. We estimated the use of olfactory and contact cues by comparing volatile emission of DP and UP, and by analysing the behaviour of the females during host recognition after landing on the leaf surface. In the context of the preference-performance hypothesis (PPH), we also tested if oviposition site selection maximizes offspring fitness by evaluating neonate hatching, larval performance and survival of larvae that were born and bred on either DP or UP. Our results demonstrate that previous conspecific herbivory on S. humboldtiana has a dramatic impact on female oviposition choices and offspring performance of the sawfly N. oligospilus. Females showed a marked preference for laying eggs on UP of S. humboldtiana. This preference was found for both local and systemic treatments. Volatile emission was quantitatively changed after conspecific damage suggesting that it could be related to N. oligospilus avoidance. In the dual choice preference experiments, the analysis of the behaviour of the females once landing on the leaf surface suggested the use of contact cues triggering egg laying on leaves from UP and avoidance of leaves from DP. Furthermore, 48 h of previous conspecific feeding was sufficient to dramatically impair neonate hatching, as well as larval development and survival, suggesting a rapid and effective reaction of the induced resistance mechanisms of the tree. In agreement with the PPH, these results support the idea that decisions made by colonizing females may result in optimal outcomes for their offspring in a barely studied insect model, and also opens the opportunity for studying tree-induced defences in the unexplored South American willow S. humboldtiana.


Asunto(s)
Himenópteros/fisiología , Oviposición/fisiología , Salix , Animales , Conducta Animal/fisiología , Conducta de Elección , Femenino , Herbivoria , Himenópteros/crecimiento & desarrollo , Larva/crecimiento & desarrollo , Odorantes , Hojas de la Planta/química , Salix/química , Compuestos Orgánicos Volátiles/análisis
14.
Arch. cardiol. Méx ; Arch. cardiol. Méx;90(supl.1): 33-35, may. 2020.
Artículo en Español | LILACS | ID: biblio-1152840

RESUMEN

Resumen Las comunicaciones acumuladas en las últimas semanas dejan claro que no existe un acuerdo para definir la mejor estrategia de tratamiento en los pacientes con un síndrome coronario agudo (SICA). En los pacientes que se presentan con un infarto agudo del miocardio con elevación del segmento ST (IAMCESST) se ha sugerido privilegiar la fibrinólisis (FL) sobre la intervención coronaria percutánea primaria (ICPp), reservando el ICP para los casos de FL fallidar1,2; sin embargo algunas sociedades han mantenido la indicación de la ICPp como el método de repercusión de elecciónr3. En los SICA sin elevación del segmento ST (SICASESST) las recomendaciones son muy similares, favoreciendo el tratamiento medico sobre el intervencionismo coronario percutáneo, en este subgrupo de pacientes1. Varias sociedades consideran el estado de contagio, en particular en los SICASESST, para decidir que estrategia de repercusión seguir3. Anticipando que la curva epidemiológica en México será similar a la observada en la mayoría de los países, recomendamos continuar la atención de los pacientes con SICA, las salas de cateterismo deben mantener su funcionamiento.


Abstract The communications accumulated in the last weeks make it clear that there is no agreement to define the best treatment strategy in patients with acute coronary syndrome (SICA). In patients presenting with an acute myocardial infarction with ST-segment elevation (IAMCESST), it has been suggested to favor fibrinolysis (FL) over primary percutaneous coronary intervention (PCI), reserving ICP for cases of failed FL1,2; however, some societies have maintained the indication of the ICPp as the repercussion method of choice3. In SICAs without ST segment elevation (SICASESST) the recommendations are very similar, favoring medical treatment over percutaneous coronary intervention in this subgroup of patients1. Several companies consider the contagion status, particularly in the SICASESST, to decide which repercussion follow3. Anticipating that the epidemiological curve in Mexico will be similar to that observed in most countries, we recommend continuing the care of patients with SICA, the catheterization rooms must maintain their operation.


Asunto(s)
Humanos , Neumonía Viral/epidemiología , Infecciones por Coronavirus/epidemiología , Síndrome Coronario Agudo/terapia , Neumonía Viral/prevención & control , Cateterismo Cardíaco , Brotes de Enfermedades , Infecciones por Coronavirus/prevención & control , Síndrome Coronario Agudo/fisiopatología , Pandemias/prevención & control , Intervención Coronaria Percutánea/métodos , Infarto del Miocardio sin Elevación del ST/fisiopatología , Infarto del Miocardio con Elevación del ST/fisiopatología , Infarto del Miocardio con Elevación del ST/terapia , COVID-19 , México/epidemiología
15.
Bull Entomol Res ; 109(5): 633-642, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30732661

RESUMEN

Volatile organic compounds (VOCs) released by plants are generally involved in host recognition and host selection for many phytophagous insects. However, for leafhoppers and planthoppers, host recognition is mainly thought to involve a phototactic response, but it is not clear if a host plant could be selected based on the volatile cues it emits. In this study we evaluated olfactory responses in dual choice tests of two Hemiptera species, Dalbulus maidis (De Long) (Cicadellidae) and Peregrinus maidis (Ashmead) (Delphacidae), vectors of maize-stunting diseases, to three maize (Zea mays L.) germplasms, a temperate and a tropical hybrid and a landrace. VOCs emitted by the germplasms were collected and identified using gas chromatography-mass spectrometry. The temperate hybrid released significantly more VOCs than the tropical hybrid and the landrace, and its volatile profile was dominated by (±)-linalool. D. maidis preferred odours emitted from the temperate hybrid, whereas P. maidis preferred odours from the tropical hybrid and the landrace over the temperate one. In order to test if linalool plays a role in the behavioural responses, we assayed this compound in combination with the tropical hybrid, to provide other contextual olfactory cues. D. maidis was attracted to the tropical hybrid plus a 0.0001% linalool solution, indicating that this compound could be part of a blend of attractants. Whereas addition of linalool resulted in a slight, though not significant, reduction in host VOC attractiveness for P. maidis. Both hopper species responded to olfactory cues in the absence of supplementary visual cues.


Asunto(s)
Hemípteros/fisiología , Olfato , Compuestos Orgánicos Volátiles/farmacología , Zea mays/química , Monoterpenos Acíclicos/farmacología , Animales , Conducta Apetitiva/fisiología , Conducta de Elección , Insectos Vectores/fisiología , Zea mays/clasificación
16.
Plant Biol (Stuttg) ; 21 Suppl 1: 84-94, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29444373

RESUMEN

Temperate grasses, such as wheat, become compact plants with small thick leaves after exposure to low temperature. These responses are associated with cold hardiness, but their underlying mechanisms remain largely unknown. Here we analyse the effects of low temperature on leaf morpho-anatomical structure, cell wall composition and activity of extracellular peroxidases, which play key roles in cell elongation and cell wall thickening, in two wheat cultivars with contrasting cold-hardening ability. A combined microscopy and biochemical approach was applied to study actively growing leaves of winter (ProINTA-Pincén) and spring (Buck-Patacón) wheat developed under constant warm (25 °C) or cool (5 °C) temperature. Cold-grown plants had shorter leaves but longer inter-stomatal epidermal cells than warm-grown plants. They had thicker walls in metaxylem vessels and mestome sheath cells, paralleled with accumulation of wall components, predominantly hemicellulose. These effects were more pronounced in the winter cultivar (Pincén). Cold also induced a sharp decrease in apoplastic peroxidase activity within the leaf elongating zone of Pincén, and a three-fold increase in the distal mature zone of the leaf. This was consistent with the enhanced cell length and thicker cell walls in this cultivar at 5 °C. The different response to low temperature of apoplastic peroxidase activity and hemicellulose between leaf zones and cultivar types suggests they might play a central role in the development of cold-induced compact morphology and cold hardening. New insights are presented on the potential temperature-driven role of peroxidases and hemicellulose in cell wall dynamics of grasses.


Asunto(s)
Pared Celular/metabolismo , Frío , Peroxidasa/metabolismo , Hojas de la Planta/anatomía & histología , Hojas de la Planta/fisiología , Triticum/anatomía & histología , Triticum/fisiología , Proteínas de Plantas/metabolismo , Polisacáridos/metabolismo , Estaciones del Año
18.
AIDS Res Ther ; 15(1): 16, 2018 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-30368240

RESUMEN

BACKGROUND: Non-AIDS defining cancers (NADCs) have been an increasing cause of morbidity and mortality in patients with HIV. There is no data on the spectrum of NADCs in Mexico. We describe the type of neoplasms, clinical characteristics, and outcomes of HIV-infected patients with NADCs. METHODS: We conducted a retrospective study of all patients with confirmed diagnosis of NADC attending the HIV/AIDS clinic at the National Cancer Institute in Mexico City (a tertiary-care center for adult patients with cancer) from January 1990 to December 2016. RESULTS: From 1126 HIV-positive individuals seen at the institute since 1990, 127 (11.3%) were diagnosed with NADCs; seven patients developed two NADCs during their follow-up. At diagnosis of NADC median age was 43.7 ± 10.9 years; 101 (79.5%) were male; median CD4 was 273 cells/mm3, 70 patients had a CD4 count of > 200 cells/mm3, 73 had undetectable HIV viral load and 82 had taken combined antiretroviral therapy (cART) for more than 1 year. The most frequent NADCs were in men, Hodgkin lymphoma (34.3%) followed by anal cancer (15.7%), whereas in women, were vulvo-vaginal cancers associated to human papilloma virus (HPV) (51.8%), followed by breast cancer (25.9%). The main risk factor associated with death was cancer progression or relapse (OR, 28.2, 2.5-317.1; p = 0.007). CONCLUSIONS: HL- and HPV-related neoplasms are the commonest NADC in a cancer referral hospital from a middle-income country with universal access to cART since year 2005. Screening for early anogenital lesions should be emphasized in patients with HIV. It is essential to establish multidisciplinary groups involving Hemato-oncologists, Oncologists, Gynecologists, and HIV Specialists in the treatment of these patients.


Asunto(s)
Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Neoplasias/complicaciones , Neoplasias/epidemiología , Centros de Atención Terciaria , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/epidemiología , Síndrome de Inmunodeficiencia Adquirida/inmunología , Síndrome de Inmunodeficiencia Adquirida/virología , Adulto , Recuento de Linfocito CD4 , Coinfección , Femenino , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Neoplasias/inmunología , Medición de Riesgo , Factores de Riesgo , Carga Viral
19.
Phytother Res ; 32(9): 1750-1754, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29726034

RESUMEN

The flavonoids comprise a large class of plant metabolites distributed in food plants. These compounds have antioxidant, antitumor, antiallergic, and anti­inflammatory effects. The molecular mechanisms of their biological activities remain to be clearly understood. We investigated the in vitro anti­inflammatory potential of a flavonoid mixture and isolated compounds from the leaves of Boldoa purpurascens. Our results provide direct evidence of the anti­inflammatory effects of the mixture, which are mediated by the inhibition of the proinflammatory cytokines tumor necrosis factor α and interleukin 6 as well as the modulation of the expression of cyclooxygenase 2.


Asunto(s)
Inhibidores de la Ciclooxigenasa/farmacología , Flavonoides/farmacología , Interleucina-6/metabolismo , Macrófagos/efectos de los fármacos , Nyctaginaceae/química , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Antiinflamatorios/farmacología , Ciclooxigenasa 2/metabolismo , Lipopolisacáridos , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Extractos Vegetales/farmacología , Hojas de la Planta/química
20.
Phys Chem Chem Phys ; 20(8): 5674-5682, 2018 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-29424846

RESUMEN

In the course of (electro)catalytic reactions, reversible and irreversible changes, namely the formation of adsorbed poisons, catalyst degradation, surface roughening, etc., take place at distinct time-scales. Reading the transformations on the catalyst surface from the measurement of the reaction rates is greatly desirable but generally not feasible. Herein, we study the effect of random surface defects on Pt(100) electrodes toward the electro-oxidation of methanol in acidic media. The surface defects are gently generated in situ and their relative magnitudes are reproducibly controlled. The system was characterized under conventional conditions and investigated under an oscillatory regime. Oscillatory patterns were selected according to the presence of surface defects, and a continuous transition from large amplitude/low frequency oscillations (type L) on smooth surfaces to small amplitude/high frequency oscillations (type S) on disordered surfaces was observed. Importantly, self-organized potential oscillations were found to be much more sensitive to the surface structure than conventional electrochemical signatures or even other in situ characterization methods. As a consequence, we proved the possibility of following the surface fine structure in situ and in a non-invasive manner by monitoring the temporal evolution of oscillatory patterns. From a mechanistic point of view, we describe the role played by surface defects and of the adsorbed and partially oxidized, dissolved species on the oscillations of type S and L.

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