An accessible method to standardize polyethylene microsphere (<100 µm) concentrations for zooplankton ingestion experiments.

The ubiquity of microplastics has caused alarm as to the impact of these materials on aquatic life, leading to experimental studies to understand these effects. In zooplankton bioassays, microspheres (Ms) are often used as a proxy to represent aquatic microplastic contamination due to their homogeneity and small sizes (<100 µm). The present study proposes an accessible protocol that does not require highly specialized equipment for the creation of Ms stock solutions and environmentally realistic experimental concentrations and describes some common issues. Adult females of the calanoid copepod Centropages furcatus underwent treatments of two Ms sizes at experimental concentrations of 10 Ms/mL. They consumed on average 0.9 ± 2.6 Ms/mL of 45-53 µm Ms, and 2.4 ± 1.1 Ms/mL of 38-45 µm Ms. The results are not directly comparable with other studies due to the wide variety of methods used but successfully demonstrate the reproducibility of the proposed protocol.

Eutrophication assessment and environmental management perspectives of Tóbari: an arid subtropical coastal lagoon of the Gulf of California.

Coastal lagoons are vulnerable to eutrophication processes. In this study, we evaluate the eutrophication process in the restricted, arid subtropical Tóbari coastal lagoon, located in the eastern coast of the Gulf of California, where the main source of nutrient inputs and other pollutants is agricultural wastewater from the Yaqui Valley. The Assessment of Estuarine Trophic Status (ASSETS) model and the Trophic State Index (TRIX) were used to evaluate eutrophication. Overall, ASSETS showed that the Tóbari lagoon has a moderate eutrophication process, with seasonal symptoms of hypoxia, increased phytoplankton biomass, dominance of macroalgae (indicative of nutrient enrichment), and blooms development of potentially harmful algae species. The TRIX showed that the lagoon is mesotrophic most of the year. Challenges of environmental management detected correspond to reducing the input of nutrients and others contaminants from anthropic sources: agriculture, shrimp farming, livestock, and urban zones.

Isolation and characterization of infectious Vibrio sinaloensis strainsfrom the Pacific shrimp Litopenaeus vannamei (Decapoda: Penaeidae)

Infectious diseases especially those caused by bacterial and viral pathogens are serious loss factors in shrimp farming. In this study, bacteria were isolated from the gut and hepatopancreas of stressed shrimps obtained from a commercial farm. The isolates were screened on Thiosulfate citrate bile salt sucrose (TCBS) agar plates for the selection of Vibrio species. Presumptive vibrios were characterized through tests for hemolytic and enzymatic activity, hydrophobicity, growth and molecular identification. Three experimental infections were conducted in order to confirm the pathogenicity of selected bacterial strains VHPC18, VHPC23, VHPC24 and VIC30. In the third experimental challenge the LD50 was obtained, it lasted 10 days with 10 shrimp, weighing 6.9±1.1g, per tank. The treatments in triplicate were: (1) saline solution (control group); (2) 2×10(5)CFU/shrimp; (3) 4×10(5)CFU/shrimp; (4) 2×10(6)CFU/shrimp; (5) 4×10(6)CFU/shrimp, and (6) 8×10(6)CFU/shrimp. In all challenges, water parameters measured during the experimental period remained within optimum ranges. Pathogenicity tests confirmed that the mixture of four vibrio isolates, identified as Vibrio sinaloensis, was virulent for L. vannamei. The LD50 value was 1.178×10(5)CFU/g body weight. V. sinaloensis may act as opportunistic pathogens for cultured L. vannamei. Rev. Biol. Trop. 60 (2): 567-576. Epub 2012 June 01.

Las enfermedades de etiología infecciosa, especialmente las causadas por patógenos bacterianos y virales ocasionan graves pérdidas en el cultivo de camarón blanco Litopenaeus vannamei. En este estudio se caracterizo: la actividad enzimática y hemolítica; hidrofobicidad; crecimiento e identificación molecular de vibrios aislados del intestino y hepatopancreas de camarones estresados, obtenidos de una granja comercial, en medio Agar Tiosulfato Citrato Bilis Sacarosa. Además, se realizaron tres infecciones experimentales para confirmar la patogenicidad de las cepas bacterianas seleccionadas VHPC18, VHPC23, VHPC24 y VIC30. En la tercera infección experimental se obtuvo la LD50, el reto duro 10 días, con 10 camarones por tanque con un peso de 6.9±1.1g. Los tratamientos se realizaron por triplicado: (1) solución salina (grupo control); (2) 2×10(5)UFC/camarón; (3) 4×10(5)UFC/camarón; (4) 2×10(6)UFC/camarón; (5) 4×10(6)UFC/camarón y (6) 8×10(6)UFC/camarón. En todos los retos, los parámetros del agua permanecieron dentro de los intervalos óptimos. Las pruebas de patogenicidad confirmaron que la mezcla de cuatro aislados de Vibrio, identificados como Vibrio sinaloensis, fue virulenta para L. vannamei. El valor de la LD50 fue de 1.178×10(5)UFC/g de peso corporal. Los resultados permiten establecer que las cepas de V. sinaloensis pueden actuar como patógenos oportunistas en L. vannamei cultivado.

Isolation and characterization of infectious Vibrio sinaloensis strains from the Pacific shrimp Litopenaeus vannamei (Decapoda: Penaeidae).

Infectious diseases especially those caused by bacterial and viral pathogens are serious loss factors in shrimp farming. In this study, bacteria were isolated from the gut and hepatopancreas of stressed shrimps obtained from a commercial farm. The isolates were screened on Thiosulfate citrate bile salt sucrose (TCBS) agar plates for the selection of Vibrio species. Presumptive vibrios were characterized through tests for hemolytic and enzymatic activity, hydrophobicity, growth and molecular identification. Three experimental infections were conducted in order to confirm the pathogenicity of selected bacterial strains VHPC18, VHPC23, VHPC24 and VIC30. In the third experimental challenge the LD50 was obtained, it lasted 10 days with 10 shrimp, weighing 6.9+1. Ig, per tank. The treatments in triplicate were: (1) saline solution (control group); (2) 2xl0(5)CFU/shrimp; (3) 4xl05CFU/shrimp; (4) 2x10(6)CFU/shrimp; (5) 4x10(6)CFU/shrimp, and (6) 8x10(6)CFU/shrimp. In all challenges, water parameters measured during the experimental period remained within optimum ranges. Pathogenicity tests confirmed that the mixture of four vibrio isolates, identified as Vibrio sinaloensis, was virulent for L. vannamei. The LD50 value was 1.178x10(5)CFU/g body weight. V sinaloensis may act as opportunistic pathogens for cultured L. vannamei.

[Maternal and fetal morbidity in patients with premature rupture of the membrane after 27-week gestation. Causes and costs]. / Condiciones atribuibles y costos de la morbilidad materno-fetal en pacientes con ruptura prematura de membranas después de las 27 semanas de gestación.

Premature rupture of the membranes (PROM) occurs in a third of the childbirths preterm, this represents 8% of all pregnancies, with same morbidity and mortality in developing and developed countries, PROM is the more common cause of neonatal morbidity and mortality, making this obstetric complication a worldwide problem of health, since it contributes to the economic problem for the cost risen in medical attention for both, mothers and live birth. PROM is considered a mutifactorial entity. This study was carried out in the Hospital de Ginecología y Obstetricia of the Centro Médico "La Raza" in Mexico City, where women entered in serial form with pregnancies from 27 to 34 weeks of gestation and spontaneous PROM, without any other pathology. 120 patients were included, with 26.8 +/- 5.9 year-old age. The gestational age with more frequency of PROM were from 30 to 33 weeks, 22.5% of the patients had 4 days with PROM, 6 of this cases arrived up to 13 days with this complication at delivery. 2.5% of the patients presented deciduitis, with adequated response to the use of antibiotics. When analyzing the hospital stay, a stay was observed from 4 to 7 days (5.26 +/- 1.96 M +/- SD), with a total cost for maternal stay of 2 millions 445,650 pesos. Those babies born had an average of 23 days of hospital stay and the total cot of the days of stay was 4 millions 963,978 pesos. Other costs were the attention of maternal and pediatrics specialty, the obstetric resolution of the pregnancy, obstetric ultrasonography and crystallographies. Thus, the total costs of the attention of this complication in these patients with PROM was of 10 millions 296,988 pesos. The international reference is the American dollar that was in 10 pesos for dollar to the moment of this study. The maternal morbidity is low to that described in previous studies, but in spite of the exhaustive efforts on the prevention, prediction, diagnosis and treatment, the premature rate due to PROM has not diminished, however the rate of neonatal survival has been increased and the morbidity has diminished.

[Mortality attributable to tobacco use in Mexico]. / Mortalidad atribuible al consumo de tabaco en México.

OBJECTIVE: To study the mortality attributable to tobacco and alcohol consumption. MATERIAL AND METHODS: Deaths occurring in 1998, abstracted from the mortality statistics registry in the Coyoacan District of Mexico City, were classified by cause as: Cardiovascular Diseases, Respiratory Diseases, and Neoplasias. Relatives of the deceased were interviewed to answer a questionnaire on tobacco smoking and alcohol drinking. RESULTS: Smoking during the last ten years of life was significantly associated with cardiovascular disease in men aged 70 years or older (OR 2.06, 95% CI 1.18-3.58). Persistent smoking in the last year of life was significantly associated with deaths from neoplasias and respiratory diseases in women aged 70 years or older (OR: 7.24, 95% CI 1.71-30.53; OR: 4.82 95% CI 1.41-16.50, respectively). The regression model for cardiovascular disease showed that subjects with intense tobacco consumption were almost twice as likely to die from cardiovascular disease (OR 1.83, 95% CI 1.1-2.8, p < 0.01). The population attributable risk for cardiovascular disease was 45%. CONCLUSIONS: Tobacco smoking is an important predictor of dead among the elderly in Mexico. Tobacco control programs should also be targeted to the elderly.

Factores que influyen en el cumplimiento del control prenatal en mujeres que asisten a la atención del parto al maternológico German Urquidi de Mayo a Septiembre año 1993 / Factors that influence the fulfillment of the prenatal control in women who attend to delivery care to the matermnologico German Urquidi from May to September 1993

De todos los fenómenos a los que se enfrenta la especie humana, el nacimiento de un nuevo ser es posiblemente el más importante, singular y conmovedor, guarda relación directa con la familia y la salud del núcleo familiar, en cuanto a la reproducción constituye el pilar en que descansa una sociedad sana. No obstante la importancia durante la práctica de materno infantil se observó la inasistencia al control prenatal, siendo ésta la razón que motivó a la investigación, a determinar los factores socioeconómicos, culturales y ginecoobstétricos que influyeron en el cumplimiento del control prenatal en mujeres que asisten a la atención del parto al Maternológico Germán Urquidi de mayo a septiembre en Cochabamba