Milk production and fatty acid profile of dairy cows grazing four grass species pastures during the rainy season in small-scale dairy systems in the highlands of Mexico.

The study evaluated small-scale dairy systems with continuous grazing of pastures based on three temperate grasses festulolium (FL), tall fescue (TF), and perennial ryegrass (RG), compared with subtropical kikuyu grass (KG). All pastures were associated with white clover (Trifolium repens L.). Twelve multiparous Holstein cows were assigned to a 4 × 4 Latin square replicated three times with 14-day experimental periods. Sampling and analyses of pastures, concentrates, and animal variables followed standard procedures. FL showed a significantly (p < 0.05) higher mean sward height, but there were no differences (p > 0.05) in net herbage accumulation. There were significant differences (p < 0.05) among pastures for CP, NDF, ADF, in vitro digestibility of OM (IVOMD), and estimated metabolizable energy (eME). There were no differences (p > 0.05) between treatments for milk yield and composition, live weight, or body condition score. There were significant differences (p < 0.05) in fatty acid values for pastures in C14:0, C16:1, and C18:3n3. There were significant differences between treatments (p < 0.05) in milk contents for C18:0, C18:1t11, and C18:2c9t11. Grazing FL, TF, RG, or KY pastures showed no differences in milk yields. Higher values for C18:0, C18:1t11, and C18:2c9t11 were detected in KY, RG, and TF. RG had significantly higher MUFA than FL and higher PUFA than TF. A value under 65% of SFA, a ratio of n-6/n-3 lower than 4, and an atherogenic index of 1.7 are indicators of milk with beneficial effects for human health.

Preparation of Modified Films with Protein from Grouper Fish.

A protein concentrate (PC) was obtained from Grouper fish skin and it was used to prepare films with different amounts of sorbitol and glycerol as plasticizers. The best performing films regarding resistance were then modified with various concentrations of CaCl2, CaSO4 (calcium salts), and glucono-δ-lactone (GDL) with the purpose of improving their mechanical and barrier properties. These films were characterized by determining their mechanical properties and permeability to water vapor and oxygen. Formulations with 5% (w/v) protein and 75% sorbitol and 4% (w/v) protein with a mixture of 15% glycerol and 15% sorbitol produced adequate films. Calcium salts and GDL increased the tensile fracture stress but reduced the fracture strain and decreased water vapor permeability compared with control films. The films prepared represent an attractive alternative for being used as food packaging materials.

Activated sludge mass reduction and biodegradability of the endogenous residues by digestion under different aerobic to anaerobic conditions: Comparison and modeling.

This study was performed to identify suitable conditions for the in-situ reduction of excess sludge production by intercalated digesters in recycle-activated sludge (RAS) flow. The objective was to compare and model biological sludge mass reduction and the biodegradation of endogenous residues (XP) by digestion under hypoxic, aerobic, anaerobic, and five intermittent-aeration conditions. A mathematical model based on the heterotrophic endogenous decay constant (bH) and including the biodegradation of XP was used to fit the long-term data from the digesters to identify and estimate the parameters. Both the bH constant (0.02-0.05 d(-1)) and the endogenous residue biodegradation constant (bP, 0.001-0.004 d(-1)) were determined across the different mediums. The digesters with intermittent aeration cycles of 12 h-12 h and 5 min-3 h (ON/OFF) were the fastest, compared to the aerobic reactor. The study provides a basis for rating RAS-digester volumes to avoid the accumulation of XP in aeration tanks.

Aerobic stabilization of biological sludge characterized by an extremely low decay rate: modeling, identifiability analysis and parameter estimation.

Aerobic digestion batch tests were run on a sludge model that contained only two fractions, the heterotrophic biomass (XH) and its endogenous residue (XP). The objective was to describe the stabilization of the sludge and estimate the endogenous decay parameters. Modeling was performed with Aquasim, based on long-term data of volatile suspended solids and chemical oxygen demand (VSS, COD). Sensitivity analyses were carried out to determine the conditions for unique identifiability of the parameters. Importantly, it was found that the COD/VSS ratio of the endogenous residues (1.06) was significantly lower than for the active biomass fraction (1.48). The decay rate constant of the studied sludge (low bH, 0.025 d(-1)) was one-tenth that usually observed (0.2d(-1)), which has two main practical significances. Digestion time required is much more long; also the oxygen uptake rate might be <1.5 mg O2/gTSSh (biosolids standards), without there being significant decline in the biomass.

[p53 expression in the gastric mucosa of patients infected with Helicobacter pylori]. / p53 expresado en la mucosa gástrica de pacientes infectados por Helicobacter pylori.

BACKGROUND: Helicobacter pylori (Hp) is recognized as a type 1 carcinogen for gastric cancer associated with pre-neoplastic lesions (atrophy and intestinal metaplasia [IM]). Its relation with p53, which intervenes in the cell cycle, has had contradictory results. AIMS: To analyze p53 expression in gastric mucosa and its relation with Hp infection. METHODS: A 3-month prospective, observational, cross-sectional study was conducted. Patients that had no evidence of acute or clinically significant gastric pathology had biopsies taken according to the Sydney system at the Hospital Juárez de México and the histopathologic studies were done at the Hospital Español de México. RESULTS: Hp prevalence was 32.7% in 104 patients. There were no cases of atrophy or dysplasia. A total of 91% of the infected patients were positive for p53. Of the non-infected patients, 14% were positive for p53 and 60% of them had IM. Of the IM patients, 75% presented with positive p53. Of the patients without IM, 31 presented with positive p53, and Hp was positive in 85% of them. There was association between Hp and p53 and between p53 and IM (P<.0001 and P<.0006, respectively). CONCLUSIONS: Significant association was shown between Hp and p53 expression, even in patients with pre-neoplastic lesions that no longer presented with Hp. Given that the identification of pre-neoplastic lesions is important for the prevention of cancer, immunohistochemistry could benefit routine biopsy carried out during endoscopy for the detection of Hp, by identifying patients with expression of the important oncogene regulator, p53.

Population-based study of cutaneous malignant melanoma in the Granada province (Spain), 1985-1992.

Cutaneous melanoma has received substantial attention during the last years because of the increase in its incidence which has been registered in many countries. This paper aims at describing the incidence and characteristics of all new cutaneous malignant melanoma cases during 1985-1992 reported to the Granada Cancer Registry (Spain) in the context of Mediterranean populations. A population-based study with 247 cutaneous melanoma cases was carried out. The variables used were: sex, age, anatomic site, hystological type, level of invasion and tumour thickness. The Age-Standardised incidence Rate per World population (ASRW) was 2.9 for males and 3.7 for females in the whole period. An increasing incidence trend for both males and females was found. The ASRW in 1985-1987, 1988-1990 and 1991-1992 was respectively 2.2, 2.9 and 3.2 for males and 3, 3.4, 4.7 for females. The most frequent location was trunk for males (36%) and lower extremities for females (44%). The most frequent hystological type for both males and females was superficial spreading melanoma. Seventy-six percent of males and 60% of females were diagnosed Clark's level III or over. Average tumour thickness was 3.3 mm for males and 2.4 mm for females. The results of this study can be a guidance for the setting up of health policies which would contribute to the prevention of the disease and to an improvement in care. Because of the increase in incidence rates and the high percentage of cases which were diagnosed at advanced stages, it is advised that prevention campaigns are addressed to the Granada population.

Comparison of fatty acid profile in plasma phospholipids in women from Granada (southern Spain) and Malmö (southern Sweden).

We conducted a first pilot study on healthy women living in two countries with different dietary habits, Granada in the south of Spain and Malmö in the south of Sweden, in order to compare their levels of plasma phospholipid fatty acids, and to examine the relationship between the differences in food consumption. This study is part of a pilot study which is nested in the European Prospective Investigation into Cancer and Nutrition, a multi-centre prospective cohort study on diet, plasma concentrations of antioxidants and fatty acids, and markers of oxidative stress. Thirty-nine women in Granada and thirty-eight women in Malmö, aged 45-50 years (all pre-menopausal) were selected among the female participants in the cohorts from these two countries. Individual measurements of the women's habitual diet were obtained by a food frequency questionnaire. 24-hour diet recalls were used for the standardised measurement of diet at group level. Plasma phospholipid fatty acid composition was determined by capillary gas chromatography. We found a different fatty acid profile in plasma between the two populations, with higher mean levels of palmitic acid (16:0), palmitoleic acid (16:1) (n-7), oleic acid (18:1), alpha-linolenic acid (18:3) (n-3) and eicosapentaenoic acid (20:5) (n-3), and lower mean levels of stearic acid (18:0) in Malmö compared to Granada. Women in Malmö consumed more meat, alcoholic beverages and sugar, and less fish and shellfish than women in Granada. We conclude that the fatty acid composition in plasma phospholipids is different between women from the two European centres. For polyunsaturated fatty acids, differences were observed for (n-3) fatty acids. In relation to these differences, we observed that specific food intakes, particularly meat and fish, varied between the two centres.

Plasma carotenoids in relation to food consumption in Granada (southern Spain) and Malmö (southern Sweden).

We conducted a cross-sectional pilot study on healthy pre-menopausal women (aged 45-50 years) living in Granada, in the south of Spain (n = 39) and Malmö, in the south of Sweden (n = 38) in order to compare their plasma carotenoid levels and to investigate the relationship between the differences in food consumption. Plasma concentrations of six carotenoids were measured using high performance liquid chromatography, habitual diet (at individual level) was estimated by food frequency questionnaires and 24-hour diet recalls were used for standardised measurement of diet at group-level. We found that women in Granada consumed more fruit and vegetables than women in Malmö. Plasma concentrations of beta-cryptoxanthin, lycopene, zeaxanthin, total carotenoids and alpha-tocopherol were higher in Granada than in Malmö, although plasma concentrations of alpha-carotene and retinol were higher in Malmö. Both within and between study centres, consumption of fruit and vegetables correlated positively with plasma concentrations of different carotenoids. The study showed that differences in consumption of fruit and vegetables between the two European centres were reflected in plasma carotenoid concentrations.

[The prediction of the cancer incidence and mortality rates in Spain for the year 2000]. / Predicción de las tasas de incidencia y mortalidad por cáncer en España para el año 2000.

OBJECTIVE: To forecast the cancer incidence and mortality rates in Spain for the year 2000, and to estimate the number of new cases and the number of dead patients due to the cancer for this year. DESIGN: Ecological study with time series analysis. PATIENTS: Cancer mortality rates in Spain was obtained from 1905 to 1995. MEASUREMENTS AND RESULTS: Brow method was applied in order to forecast cancer mortality rates for the year 2000. An estimation of the incidence rates in Spain was obtained from the incidence/mortality rate (1.49 for males and 2.07 for females), given by the International Agency for Research on Cancer (IARC). INE's publications were used in order to estimate the number of new cases and the number of dead patients due to the cancer for the year 2000. The forecasting about cancer mortality rates in Spain for the year 2000 were 312.93 in men and 180.56 in women. An increasing in mortality will be produced in the following years. 90,000 men and 75,000 women will be diagnosed with cancer; 61,000 men and 36,000 women will be died due of this disease. CONCLUSION: The trends in cancer incidence and mortality are increasing. These results could be interesting in health policy in order to plan different actions in the future.

Seroepidemiology of the hepatitis B and delta in the southeast of Chiapas, Mexico.

An area of high endemicity for hepatitis B and delta antigen was identified in the southern border of Mexico (Chiapas). The study included individuals from mexican communities and guatemalan refugee camps. 91.1% of the subjects were positive to anti-HBcAg antibodies. The frequency of asymptomatic carriers of HBsAg went from 4.2% in mexican communities to 17.3% in guatemalan refugee camps, the percentage was higher in households with six or more persons per room (14.0 per 100 individuals). The prevalence of e antigen in subjects positive to HBsAg was higher among guatemalan refugees (35.3%) than among mexicans (7.7%). A refugee camp, Benemerito de las Americas, showed 65.6% positives to anti-HBcAg antibodies and 39.0% asymptomatic HBsAg carriers, 41.7% of these were positive to HBeAg. Antidelta antibodies were present in 50 of 119 subjects positive to HBsAg. The mechanism of transmission was mainly horizontal since most of the infected children in each household corresponded to the oldest offspring. Our data were similar to those observed in the amazonian region of Brazil, Southeast Asia and tropical Africa.