Isolation of Babesia spp. from asymptomatic human beings     

B.Miguel Osorno  Carlos Vega  Miodrag Ristic  Carlos Robles  Samuel Ibarra 《Veterinary parasitology》1976,2(1):111-120

Babesiosis is a worldwide tick-borne protozoan disease of a variety of wild and domestic animals. For decades, various babesia strains were considered host-specific. However, babesiosis has been diagnosed as the cause of acute illness in 13 human beings in recent years, three of whom died. Studies of babesiosis in domestic animals indicate that for every clinically demonstrable case, there are hundreds of cases of latent infection. In an effort to determine if human babesia infections might be present in Mexico, we selected as our testing ground an endemic rural area along the Gulf Coast where continuous epizootics of equine, bovine, ovine and canine babesiosis were known to occur. Of the 101 individuals examined serologically by the indirect hemagglutination (IHA) test using Babesia canis as antigen, 38 reacted at titers from 1 : 10 to 1 : 80. Blood from these reactors was injected into splenectomized hamsters. Hamsters inoculated with blood from three of the individuals showed babesia in their peripheral blood. The growth of the organism was established by subpassages into additional hamsters. The persons from whom the organisms were isolated were asymptomatic for babesiosis. None of the 29 individuals residing in Mexico City, which represented the urban population in the survey, reacted in the IHA test. This is the first documented finding of the latent form of human babesiosis.  相似文献   

Bacillary haemoglobinuria diagnosis by the peroxidase-antiperoxidase (PAP) technique.     

F A Uzal  K Belak  E Rivera  C A Robles  R E Feinstein 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1992,39(8):595-598

A peroxidase-antiperoxidase (PAP) technique was used to diagnose bacillary haemoglobinuria in formalin-fixed, paraffin-embedded liver tissues of cattle. The PAP method revealed Clostridium haemolyticum in the zone of liver necrosis characteristic of the disease and also in culture smears of this microorganism, but C. novyi type B, C. chauvoei, C. septicum and C. perfringens types B and C remained unstained by the PAP reaction. The PAP technique performed provides a specific, simple and rapid method to diagnose bacillary haemoglobinuria.  相似文献   

Feedback regulation of transcriptional termination by the mammalian circadian clock PERIOD complex   总被引：1，自引：0，他引：1  

K Padmanabhan  MS Robles  T Westerling  CJ Weitz 《Science (New York, N.Y.)》2012,337(6094):599-602

  相似文献   

Repeated cross‐sectional study of Trypanosoma cruzi in shelter dogs in Texas,in the context of Dirofilaria immitis and tick‐borne pathogen prevalence     

Carolyn L. Hodo  Jessica Y. Rodriguez  Rachel Curtis‐Robles  Italo B. Zecca  Karen F. Snowden  Kevin J. Cummings  Sarah A. Hamer 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(1):158-166

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Bottled-Water Quality in Metropolitan Mexico City     

Robles  Esperanza  Ramírez  Pedro  Elena González  Ma.  de Guadalupe Sáinz  Ma.  Martínez  Blanca  Durán  Angel  Elena Martínez  Ma. 《Water, air, and soil pollution》1999,113(1-4):217-226

Bacteriological and physico-chemical parameters of 265 samples from 39 brands sold in 5-gallon plastic and glass bottles and 2-5 L plastic containers were analyzed to determine the quality of bottled water distributed in Mexico City. Tests included fecal and total coliform counts, alkalinity, total hardness, chloride, calcium and magnesium concentrations, pH and conductivity. Correlation and cluster analyses and ANOVA were carried out, and a comparison made of the averages with the maximum permissible levels established in the Official Mexican Norms. Concerning the investigated parameters no differences (p > 0.05) between the brands were found. Physico-chemical parameters were studied and all the samples were within the permissible limits. Most samples taken from the 5-gallon containers exceeded the maximum bacteriological limits. It was concluded that the bacteriological quality of the brands studied was extremely variable. Appropriate sanitary measures, should be established to control this aspect.  相似文献   

Fluctuating salinity effect on Sphoeroides annulatus (Jenyns 1842) physiological responses     

Javier Prez‐Robles  Ana Denisse Re‐Araujo  Maricela Cortez‐García  Fernando Díaz  Leonardo Ibarra‐Castro  Ivone Giffard‐Mena 《Aquaculture Research》2019,50(1):198-208

Euryhaline fish, such as the Bullseye puffer Sphoeroides annulatus (Jenyns 1842), experience sudden salinity changes in their natural environment, which is more common than the exception, so they must adapt to survive and cope with extreme salt conditions. Therefore, Bullseye puffer juveniles were exposed to short‐term stress (39 hr) by fluctuating salinity conditions (41, 35, 29, 23, 17, 11, 5, 11, 17, 23, 29, 35, 41 psu) with a 3‐hr interval between each point at 26 ± 1ºC in a respirometer chamber and acclimation reservoirs. Responses to oxygen consumption rate (OCR: 23–35 mg O₂ h^–1 kg^–1), ammonium excretion rate (AER: 1–1.85 mg NH4⁺ h^?1 kg^?1), oxygen‐nitrogen atomic ratio (O:N 17–30), osmoregulatory pattern (blood osmotic pressure from 342.4 to 332.8 mmol/kg) and changes in expression levels of Na⁺/K⁺‐ATPase in the gills (higher values at higher salinities) were measured. Although some signs of stress were detected below the iso‐osmotic point (11.4 psu), the puffer fish is a strong euryhaline fish that survives under these conditions. Nonetheless, it could recover when salinity returned to the initial acclimation point because Sphoeroides annulatus is able to live in a wide range of environments with wide natural salinity fluctuations; thus, a common practice in aquaculture has been to expose fish to low salinity for several reasons discussed in this study. This capacity reveals its high plasticity to saline adaptation from 41 to 5 psu an up from 5 to 41 psu, all in less than 2 days.  相似文献   

Productive behavior in growing kid goats and methane production with the inclusion of chokecherry leaf (Prunus salicifolia)     

Robles Jimenez  Lizbeth E.  Ruiz Perez  Jose A.  Nicolas  Di Lorenzo  Chay Canul  Alfonso J.  Ramirez-Rivera  Julio Cesar  Villegas-Estrada  Daniela  Vargas-Bello-Pérez  Einar  Gonzalez-Ronquillo  Manuel 《Tropical animal health and production》2020,52(3):1257-1267

Tropical Animal Health and Production - Currently for the reduction of methane (CH4) emissions are using fodder rich in condensed tannins, however, not yet known exactly how they act in the rumen...  相似文献   

Low UV-C illumination for keeping overall quality of fresh-cut watermelon     

Francisco Artés-Hernández  Pedro A. Robles  Perla A. Gómez  Alejandro Tomás-Callejas  Francisco Artés 《Postharvest Biology and Technology》2010,55(2):114-120

The effects of four pre-packaging UV-C illumination doses (1.6, 2.8, 4.8 and 7.2 kJ m^?2) on quality changes of watermelon cubes stored up to 11 days at 5 °C were studied. Non-treated cubes were used as a control. Higher UV-C doses induced slightly higher CO₂ production throughout the storage period, while no changes in C₂H₄ production were monitored. However, UV-C did not significantly affect the final gas partial pressures within modified atmosphere packages where levels of 3–6 kPa O₂ and 13–17 kPa CO₂ were reached for all treatments. UV-C decreased microbial counts just after illumination. After 11 days at 5 °C, mesophilic, psycrophilic and enterobacteria populations were significantly lower in UV-C treated watermelon. Slight changes in CIE colour parameters were observed. According to sensory quality attributes, control and low UV-C treated cubes (1.6 and 2.8 kJ m^?2) can be stored for up to 11 days at 5 °C while the maximum shelf-life of moderate to high UV-C treated fruit was 8 days at 5 °C. Control cubes showed a 16% decrease in lycopene content after 11 days at 5 °C similar to that found for the high UV-C treatment. However low UV-C treated watermelon cubes preserved their initial lycopene content (2.8 kJ m^?2) or it was slightly decreased (1.6 kJ m^?2). UV-C radiation did not significantly affect the vitamin C content while catalase activity and total polyphenols content considerably declined throughout the storage period. However, total antioxidant capacity markedly increased, independently of UV-C doses. As a main conclusion, UV-C radiation can be considered a promising tool for keeping overall quality of fresh-cut watermelon.  相似文献   

Cover crops under different managements vs. frequent tillage in almond orchards in semiarid conditions: Effects on soil quality   总被引：1，自引：0，他引：1  

María E. Ramos  Emilio Benítez  Pedro A. García  Ana B. Robles 《Applied soil ecology》2010,44(1):6-14

Frequent tillage has been widely used in rainfed orchards in SE Spain in order to impede weed establishment and to increase water reposition in the soil profile. However, this practice may lead to soil degradation by decreasing structural stability, organic carbon content and microbial activity. This work examines the effect of different cover crop managements and frequent tillage on soil physical, chemical and biological properties in almond orchards in SE Spain. Two cover crops (oat – Avena sativa L. and oat-vetch – Vicia sativa L.) with two fertilization managements (mineral and organic) and three harvesting regimes (grazing in mid May, hay in early June, and grain-straw in mid July) were compared to a frequently tilled orchard system (three or four tillages per year). Most parameters were sensitive to soil management. Wet aggregate stability, total organic carbon, total nitrogen, carbon:nitrogen ratio, phosphatase, and β-glucosidase activities increased with cover crops, whereas the soil–water content declined, especially for the grain-straw treatment. The kind of fertilizer affected the available P content, which was higher for mineral fertilizer, and influenced the β-glucosidase activity, which augmented for the organic fertilizer. Livestock dejections depressed phosphatase activity, and increased WSC and available P.This study suggests that cover crops in semiarid environments improve soil quality compared to frequently tilled management, by increasing the organic matter content, improving the chemical and physical fertility of the soil, and enhancing the soil biological activity. Only higher water extraction by the plants could affect the orchard development and/or productivity; however, early cover crop removal would minimize possible yield losses.  相似文献   

Applying biofloc technology in the culture of juvenile of Piaractus brachypomus (Cuvier, 1818): Effects on zootechnical performance and water quality     

Leydy Y. Sandoval‐Vargas  Martha N. Jimnez‐Amaya  Jos Rodríguez‐Pulido  Diana N. Guaje‐Ramírez  Juan A. Ramírez‐Merlano  Víctor M. Medina‐Robles 《Aquaculture Research》2020,51(9):3865-3878

The aim of this study was to assess the zootechnical performance and water quality of a cachama blanca (Piaractus brachypomus) culture using biofloc technology (BFT) versus a system with daily water exchange (DWE). To do this, 180 juveniles (mean initial weight: 5.40 ± 0.19 g) were distributed in 12 circular plastic tanks with stocking densities of 20 or 40 individuals m³; then, they were cultured for 91 days. BFT treatments kept a C:N ratio approximately of 15:1. Temperature, pH and oxygen were monitored daily, while the other variables were measured weekly. Most productive variables were significantly influenced by both culture system and stocking density with significantly higher values of daily weight gain, total weight gain and total length for fish kept in DWE 20. However, only minor differences were observed within the BFT system. With the exception of the toxic nitrogen compounds (NH₄⁺ and NO₂^?), all the other water quality parameters were within the acceptable ranges for the cultivation of tropical fish. Microorganisms started to settle from the first week. A total of 23 genera were present, the most outstanding of which being seven genera of ciliates and three rotifers, rhizopods and chlorophytes. In conclusion, both systems BFT and DWE are useful for increasing the production of P. brachypomus in captivity. Additionally, the BFT system can potentially be applied for growing juveniles of this specie in regions with scarce water resources.  相似文献