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1.
Lasers Med Sci ; 36(6): 1177-1189, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33011859

RESUMEN

The current research focuses on the effect of variable doses of red laser on the chick embryonic development. He-Ne laser of 632-nm wavelength was used as an irradiation source in the first 48 h post-laying of chicken eggs. We have used five different doses: 2, 1, 0.3, 0.2, and 0.1 mJ/cm2 that needed a time range for about 400-20 s. Those irradiated embryos were left for additional 11 days for incubation in normal conditions, where they are blindly studied after the 11th day. Light microscopy was used in this study to investigate the histological and pathological features of the different experimental groups compared to the control one. However, electron microcopy was utilized to trace the apoptotic distribution in the developmental embryos. Minor abnormalities that are dependent on the laser dose have been shown in the irradiated embryos when compared to the sham group, where the highest laser dose showed about 12% embryonic development anomalies when related to the other irradiated groups. Irradiated embryos were found to express more INF-γ and IL-2 as circulating cytokines relative to the unexposed group, where the levels of IL-2 were highly significantly increased by all laser doses (0.3 mJ/cm2 light dose recipient group showed significant increase only when compared to the control group). IFN-γ levels were significantly increased as well by light doses above 0.2 mJ/cm2. This IFN-γ increase trend seemed to be laser dose-dependent. Simultaneously, these combined results propose the ability of high laser doses in inducing incurable changes in the embryonic development and consequently such alterations can have potential therapeutic applications through what is known as photobiomodulation.


Asunto(s)
Terapia por Luz de Baja Intensidad/métodos , Animales , Embrión de Pollo , Relación Dosis-Respuesta en la Radiación , Factores de Tiempo
2.
Trop Anim Health Prod ; 49(3): 575-581, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28160162

RESUMEN

The aim of this study was to identify and characterize thermophilic Campylobacter species in faecal samples from goats in Khartoum State, Sudan, by application of multiplex polymerase chain reaction. Campylobacteriosis is a zoonotic disease of global concern, and the organisms can be transmitted to human via food, water and through contact with farm animals and pets. There are five clinically related Campylobacter species: Campylobacter jejuni (C. jejuni). Campylobacter coli, Campylobacter lari, Campylobacter upsaliensis and Campylobacter fetus. Conventional cultural methods to diagnose campylobacteriosis are tedious and time consuming. Wide ranges of genes have been reported to be used for PCR-based identification of Campylobacter spp. We used a multiplex PCR assay to simultaneously detect genes from the major five clinically significant Campylobacter spp. The genes selected were hipO (hippuricase) and 23S rRNA from glyA (serine hydroxymethyl transferase) from each of C. jejuni. C. coli, C. lari, and C. upsaliensis; and sapB2 (surface layer protein) from C. fetus subsp. fetus. The assay was used to identify Campylobacter isolates recovered from 336 cultured faecal samples from goats in three localities in Khartoum State. C. coli was the most predominant isolate (234; 69.6%), followed by C. jejuni (19; 5.7%), C. upsaliensis (13; 3.9%), C. fetus subsp. fetus (7; 2.1%) and C. lari (6; 1.8%). Twenty-nine goats showed mixed infection with Campylobacter spp., 21 of which harbored two Campylobacter spp., while eight animals were infected with three species. Ten out of twelve goats that displayed diarrhea harbored C. coli only. C. coli, C. jejuni and C. upsaliensis showed significant variation with localities. The prevalence of C. coli was significantly higher (87; 25.9%) in goats from Omdurman, whereas C. jejuni and C. upsaliensis were significantly higher (11; 3.3%, 9; 2.7%) in goats from Khartoum. The multiplex PCR assay was found to be rapid and easy to perform and had a high sensitivity and specificity for characterizing the isolates, even in mixed cultures. The study demonstrated the significance of goats as reservoirs in the dissemination of Campylobacter spp. which could be considered as potential agent of caprine enteritis and abortion as well as contamination of the wider environment posing serious public health concern in Khartoum State.


Asunto(s)
Infecciones por Campylobacter/veterinaria , Campylobacter/aislamiento & purificación , Enfermedades de las Cabras/diagnóstico , Carne , Animales , Campylobacter/clasificación , Infecciones por Campylobacter/diagnóstico , Infecciones por Campylobacter/epidemiología , ADN Bacteriano/análisis , Heces/microbiología , Femenino , Contaminación de Alimentos , Enfermedades de las Cabras/epidemiología , Cabras , Masculino , Reacción en Cadena de la Polimerasa Multiplex/veterinaria , Sensibilidad y Especificidad , Sudán/epidemiología
3.
Artículo en Inglés | MEDLINE | ID: mdl-31077705

RESUMEN

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). These articles are retracted at the request of the authors. The joint Editors-in-Chief agree with this decision.

4.
Prev Vet Med ; 169: 104697, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31311638

RESUMEN

Malignant theileriosis of sheep and goats caused by Theileria lestoquardi is considered to be among the most important tick borne diseases in the Sudan. Information on the prevalence of the disease in different parts of the Sudan is limited. The purpose of this study was to estimate the prevalence of the disease in five states of the Sudan using molecular and serological assays. A total of 393 blood and serum samples from clinically asymptomatic sheep were analysed using nested reverse line blot (nRLB) and loop mediated isothermal amplification (LAMP), as well as an enzyme-linked immunosorbent assay (ELISA). The results indicated a sero-prevalence of 33.8% while RLB and LAMP assays revealed molecular prevalences of 29.5 and 22.6% respectively. The prevalence of Theileria lestoquardi varied significantly according to the geographical origin of the infected animals, whereas age and gender did not have a significant effect. RLB data indicated that T. lestoquardi usually occurred as a co-infection with the non-pathogenic Theileria ovis. Using RLB as a gold standard, a sensitivity of 68.1% and a specificity of 96.4% were recorded for LAMP and a sensitivity of 75.9% and a specificity of 83.8% for ELISA. The Kappa coefficient between nRLB and LAMP indicated a significant level of agreement (0.692), but only moderate concordance (0.572) between nRLB and ELISA. The results of the present study confirm and extend earlier findings regarding the widespread of T. lestoquardi infections in sheep in the Sudan. The data provide evidence that should enable the veterinary authorities to deploy appropriate control measures.


Asunto(s)
Enfermedades de las Ovejas/epidemiología , Enfermedades de las Ovejas/parasitología , Theileria/aislamiento & purificación , Theileriosis/epidemiología , Animales , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Geografía , Masculino , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , Ovinos , Enfermedades de las Ovejas/sangre , Sudán/epidemiología , Theileriosis/sangre
5.
Onderstepoort J Vet Res ; 75(1): 47-53, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18575063

RESUMEN

In a preliminary survey conducted in 2005, the species composition and seasonality of ticks infesting cattle in Central Equatoria State, Southern Sudan was determined. Three locations were selected (Gumbo, Khor Rumla and Nyaing) and surveyed every 3 months. Two cattle herds in each of the three locations were visited four times during the study period. Total body collections of ticks were made from each of five cattle (Nilotic Zebu breed) kept in six different herds. Four tick genera and ten species were identified. The tick species identified were Amblyomma lepidum, Amblyomma variegatum, Boophilus annulatus, Boophilus decoloratus, Hyalomma marginatum rufipes, Hyalomma truncatum, Rhipicephalus appendiculatus, Rhipicephalus evertsi evertsi, Rhipicephalus praetextatus and Rhipicephalus sanguineus group. The highest number of ticks was collected in October during the rainy season. A finding of great significance was that R. appendiculatus, vector of East Coast fever, has now firmly established itself throughout the year with possible implications for cattle production in Central Equatoria State.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Filogenia , Infestaciones por Garrapatas/veterinaria , Garrapatas , Animales , Bovinos , Enfermedades de los Bovinos/transmisión , Femenino , Masculino , Estaciones del Año , Vigilancia de Guardia/veterinaria , Especificidad de la Especie , Sudán/epidemiología , Theileriosis/epidemiología , Theileriosis/transmisión , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/transmisión , Garrapatas/clasificación , Garrapatas/crecimiento & desarrollo , Garrapatas/parasitología
6.
Vet Parasitol Reg Stud Reports ; 13: 24-29, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-31014883

RESUMEN

This survey was conducted to detect Theileria annulata infection in indigenous (Zebu) and cross (indigenous × Friesian) cattle (n 604) of different sex & age groups, and to investigate prevalence of ticks infesting cattle in North Kordofan State, Sudan. Ticks, blood smears, serum samples and blood spots on filter paper were collected from four municipalities at four monthly intervals during the period from August 2008 to July 2009. Out of 604 blood smears, 69 (11.4%, 95% CI: 16.9-5.9) were positive for Theileria piroplasms; whereas, out of 240 serum samples, 164 (68.3%, 95% CI: 89.3-47.3) were positive for antibodies against T. annulata using IFA test. Using PCR, out of 100 blood spots on filter paper, 8 (8%, 95% CI: 9.6-6.4) revealed T. annulata DNA. The highest prevalence of Theileria spp. piroplasms and T. annulata antibodies was recorded in August (15.9 ±â€¯4.6) followed by February (13.3 ±â€¯3.8) and the lowest was in May (3.9 ±â€¯1.0). Among cattle breeds, the highest prevalence of piroplasms (11.9 ±â€¯5.0) and T. annulata antibodies (68.9 ±â€¯10) was among zebu cattle. PCR assays revealed the highest prevalence rate of T. annulata DNA in February (12.5 ±â€¯1.4) followed by August (6.1 ±â€¯0.7) and the lowest was in May (5.7 ±â€¯0.7). According to cattle breeds, T. annulata DNA was detected in cross-bred cattle (3.3 ±â€¯0.4) more than zebu cattle (10 ±â€¯1.6). Seven tick species belonging to four genera and were identified, Amblyomma lepidum, Hyalomma dromedarii, H. impeltatum, H. rufipes, Rhipicephalus evertsi evertsi, Rhipicephalus decoloratus, R. annulatus. The most abundant tick species was H. rufipes followed by H. impeltatum, R. e. evertsi, H. dromedarii, R. decoloratus, A. lepidum and R. annulatus. Theileria annulata has been detected for the first time in North Kordofan State, though at a low prevalence rate. This finding is an alarming situation since tropical theileriosis is an emerging disease and it is widely believed that this economically important tick-borne parasite does not exist in this state. The possible alternative vector(s) of T. annulata in the absence of the known vector H. anatolicum is discussed.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Enfermedades de los Bovinos/epidemiología , Theileria annulata/genética , Theileriosis/epidemiología , Infestaciones por Garrapatas/veterinaria , Garrapatas/parasitología , Animales , Bovinos/parasitología , Enfermedades de los Bovinos/parasitología , ADN Protozoario , Femenino , Ixodidae/parasitología , Masculino , Reacción en Cadena de la Polimerasa , Prevalencia , Sudán/epidemiología , Encuestas y Cuestionarios , Infestaciones por Garrapatas/epidemiología , Garrapatas/genética
7.
Prev Vet Med ; 81(4): 323-6, 2007 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-17590458

RESUMEN

We tested the agreement between microscopic examination (ME), a surface protein-detecting enzyme-linked immunosorbent assay (TaSP ELISA) and an indirect fluorescent assay (IFA) for detection of Theileria annulata in 2,661 naturally infected cattle from northern Sudan (samples collected between June 2001 and July 2002). In the ME, we detected piroplasms in 364/2,661 cattle (14%), and the kappas between the ME and the serological tests were poor (TaSP ELISA 10%; IFA 8%). The TaSP ELISA detected 885/2,661 cattle as positive, and the Rogan-and-Gladen corrected true prevalence of this sample was estimated to be 30%. The relative sensitivity and specificity of the IFA (compared to the previously validated TaSP ELISA) were 70.7% and 81.8%, respectively.


Asunto(s)
Proteínas Protozoarias/inmunología , Pruebas Serológicas/veterinaria , Theileria annulata/inmunología , Theileria annulata/ultraestructura , Theileriosis/diagnóstico , Animales , Anticuerpos Antiprotozoarios/sangre , Bovinos , Ensayo de Inmunoadsorción Enzimática/métodos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Técnica del Anticuerpo Fluorescente Indirecta/veterinaria , Sensibilidad y Especificidad , Pruebas Serológicas/métodos , Sudán/epidemiología , Theileriosis/epidemiología , Theileriosis/parasitología
8.
Transbound Emerg Dis ; 64(4): 1229-1235, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27005905

RESUMEN

A cross-sectional survey was carried out in four counties of Jonglei State, South Sudan, between May and June 2012 to determine the distribution and northern limit of Theileria parva, the causative agent of East Coast fever in cattle, and its tick vector Rhipicephalus appendiculatus, as a prerequisite to the deployment of relevant control strategies. A total of 1636 ticks, 386 serum samples and 399 blood samples were collected from indigenous, apparently healthy, cattle of different age groups. Tick species were identified morphologically, and the identity of R. appendiculatus was confirmed by DNA barcoding. Overall, the T. parva infection rate in R. appendiculatus was 25% as shown by nested PCR. ELISA was used to assess antibodies to T. parva, and the overall seroprevalence was 22.8%. PCR of the blood samples showed 55 (13.8%) were positive for T. parva. This is the first molecular confirmation of T. parva DNA in areas north of Juba, where it was previously known and established. The northern limit of T. parva was determined as N°06.17.792, about 242 Km north from Juba. Implication of this limit on the epidemiology and control of ECF is discussed.


Asunto(s)
Ixodidae/parasitología , Theileria parva/aislamiento & purificación , Theileriosis/epidemiología , Animales , Bovinos , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática/veterinaria , Ixodidae/clasificación , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , Rhipicephalus/clasificación , Rhipicephalus/parasitología , Estudios Seroepidemiológicos , Sudán del Sur/epidemiología , Theileriosis/parasitología
9.
Vet Parasitol ; 239: 7-14, 2017 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-28495200

RESUMEN

Theileriosis, caused by parasitic protozoa of the genus Theileria parasites, are among the major tick-borne diseases of ruminant livestock. The largest economic losses are attributed in particular to those caused by the leukoproliferative species of Theileria: T. parva, T. annulata and T. lestoquardi. Theileria lestoquardi is transmitted by Hyalomma ticks and causes malignant ovine theileriosis (MOT), a disease that is particularly prevalent in Sudan. The disease is considered of a high economic importance in Sudan, where export of sheep is a major component of the national economy. A live vaccine based on a Sudanese isolate of T. lestoquardi (Atbara strain) was previously developed for the control of MOT in Sudan, but not yet deployed in the field. The present study aims to genetically characterize and compare samples of T. lestoquardi circulating in Sudan as well as the live vaccine isolate in order to understand vaccine breakthroughs and failure that may occur. Sheep and goats blood samples were collected from six regions in Sudan that are known to be endemic for T. lestoquardi infection or have experienced outbreaks of MOT. Blood samples infected with T. lestoquardi were identified by PCR or RLB. Genotyping was carried out by (1) sequencing the homologues of two T. parva CD8+ T cell antigen genes, Tp1 and Tp2, and (2) using a panel of seven micro- and mini-satellite markers. A total of 100 T. lestoquardi positive field samples and the T. lestoquardi (Atbara) vaccine were genotyped. The results showed that all samples had mixed genotypes, with several alleles identified at one or more loci. The gene diversity ranged from 0.7840 (TS8) to 0.2133 (TS12) with mean values of 0.5470. PCA revealed three clusters of the parasite in Sudan; interestingly one independent cluster was clearly seen, corresponding to the vaccine isolate. The T. lestoquardi Tp1 homologue showed higher homology with T. annulata than with T. parva sequences included the defined single CD8+ T cell target epitope region. The result indicates that multiple genotypes are a common feature of T. lestoquardi infection in Sudan. Both genotyping and the sequencing results clearly showed that the vaccine isolate is highly distinct from the field samples. This finding raised the question whether vaccination with the prepared lived vaccine will effectively protect animals against challenges by the field isolates of T. lestoquardi. The results of this work will inform on the best approach for controlling MOT in Sudan.


Asunto(s)
Enfermedades de las Cabras/parasitología , Vacunas Antiprotozoos , Enfermedades de las Ovejas/parasitología , Theileria/genética , Theileriosis/parasitología , Secuencia de Aminoácidos , Animales , Regulación de la Expresión Génica/fisiología , Técnicas de Genotipaje/métodos , Técnicas de Genotipaje/veterinaria , Enfermedades de las Cabras/epidemiología , Enfermedades de las Cabras/prevención & control , Cabras , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Ovinos , Enfermedades de las Ovejas/epidemiología , Enfermedades de las Ovejas/prevención & control , Sudán/epidemiología , Theileria/clasificación , Theileria/inmunología , Theileriosis/epidemiología , Theileriosis/prevención & control
10.
Onderstepoort J Vet Res ; 72(3): 239-43, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16300192

RESUMEN

Five species of ixodid ticks were found in a cross-sectional survey in which 200 sheep were examined for ticks in River Nile Province, Sudan. Hyalomma anatolicum anatolicum was the predominant species (73.6%), whereas ticks belonging to the Rhipicephalus sanguineus group (14.7%), Rhipicephalus evertsi evertsi (9.1%), Rhipicephalus simus (2%) and Hyalomma dromedarii (0.5%) were also found. The mean tick load was 11.2 per animal. In a subsequent longitudinal survey ticks were collected on a monthly basis from eight sentinel sheep that were introduced into the area. It was found that H. a. anatolicum almost disappeared during the hot period between April and August, whereas it's highest numbers were present in winter between November and February. It is concluded that there is only one generation of H. a. anatolicum per year, which may explain the year-round appearance of clinical cases of malignant ovine theileriosis indicating endemic instability of this disease in River Nile Province.


Asunto(s)
Ixodidae , Enfermedades de las Ovejas/epidemiología , Infestaciones por Garrapatas/veterinaria , Animales , Estudios Transversales , Femenino , Interacciones Huésped-Parásitos , Ixodidae/clasificación , Ixodidae/crecimiento & desarrollo , Larva/clasificación , Larva/crecimiento & desarrollo , Estudios Longitudinales , Masculino , Dinámica Poblacional , Estaciones del Año , Ovinos , Enfermedades de las Ovejas/parasitología , Especificidad de la Especie , Sudán/epidemiología , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitología
11.
Onderstepoort J Vet Res ; 72(4): 303-7, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16562733

RESUMEN

Hyalomma anatolicum anatolicum nymphs were collected from two localities in the Sudan: Eddamer in Northern Sudan and Wad-Medani in Central Sudan. They were allowed to moult to adult ticks, which were assessed for Theileria infection in their salivary glands using Feulgen stain. At Eddamer, 49.6% of 123 ticks examined were infected with Theileria and the mean intensity of infection was 1.3 (i.e. the number of infected acini/number of infected ticks). At Wad-Medani, 8.6% of 162 ticks were infected and the mean intensity of infection was 7.9. The prevalence of infection was higher in female than in male ticks at both localities. When adult H. a. anatolicum were applied onto two susceptible calves, both animals developed the severe form of theileriosis.


Asunto(s)
Theileria annulata/aislamiento & purificación , Theileriosis/epidemiología , Theileriosis/transmisión , Garrapatas/parasitología , Animales , Bovinos , Femenino , Masculino , Glándulas Salivales/parasitología , Factores Sexuales , Sudán/epidemiología
12.
J Environ Radioact ; 79(3): 355-67, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15607521

RESUMEN

In the first part of the paper, the factors affecting 222Rn properties in 25 different realistic living rooms (with low ventilation rates) of different houses in El-Minia City (Upper Egypt) have been studied; they included the activity concentration of 222Rn gas (C(o)), the unattached fraction (f(p)) of 218Po and 214Pb, the unattached potential alpha energy concentration (PAEC) and the equilibrium factor (F). The activity distributions of unattached 218Po and 214Pb as well as for the PAEC were determined. With a dosimetric model calculation [ICRP, 1994b. Human Respiratory Tract Model For Radiological Protection. Pergamon Press, Oxford. ICRP Publication 66] the total deposition fraction of unattached 218Po and 214Pb in human respiratory tract was evaluated to determine the total equivalent dose. An electrostatic precipitation method and a wire screen diffusion battery technique were both employed for the determination of 222Rn gas concentration and its unattached decay products, respectively. The mean activity concentration of 222Rn gas (C(o)) was found to be 110+/-20 Bq m(-3). The mean unattached activity concentrations of 218Po and 214Pb were found to be 0.6 and 0.35 Bq m(-3), respectively. A mean unattached fraction (f(p)) of 0.09+/-0.01 was obtained at a mean aerosol particle concentration (Z) of (2.9+/-0.23) x 10(3)cm(-3). The mean equilibrium factor (F) was determined to be 0.31+/-0.02. The mean PAEC of unattached 218Po and 214Pb was found to be 8.74+/-2.1 Bq m(-3). The activity distributions of 218Po and 214Pb show mean activity median diameters (AMD) of 1.5 and 1.85 nm with mean geometric standard deviations (SD) of 1.33 and 1.45, respectively. The mean activity distribution of the PAEC shows an AMD of 1.65 nm with a geometric standard deviation of 1.25. At a total deposition fraction of about 97% the total equivalent dose to the lung was determined to be about 133 microSv. The second part of this paper deals with a study of natural radionuclide contents of samples collected from the building materials of the rooms under investigations in part one. Analyses were performed in Marinelli beakers with a gamma multichannel analyzer equipped with a NaI(Tl) detector. The samples revealed the presence of the uranium-radium and thorium radioisotopes as well as 40K. Nine gamma-lines of the natural radioisotopes corresponding to 212Pb, 214Pb, 214Bi, 228Ac, 40K and 208Tl were detected and measured. The activity concentrations of 226Ra, 232Th and 40K were determined with mean activity concentrations of 58+/-19, 31+/-11 and 143+/-62 Bq kg(-1), respectively. These activities amount to a radium equivalent (Ra(eq)) of 113 Bq kg(-1) and to a mean value of external hazard index of 0.31.


Asunto(s)
Exposición a Riesgos Ambientales , Vivienda , Modelos Teóricos , Radioisótopos/análisis , Radón/análisis , Materiales de Construcción , Egipto , Monitoreo del Ambiente , Humanos , Radiometría , Medición de Riesgo , Ventilación
13.
Appl Radiat Isot ; 62(6): 955-9, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15799876

RESUMEN

Inhalation of 222Rn and 220Rn progeny from the domestic environment contributes the greatest fraction of the natural radiation exposure to the public. Dosimetric models are most often used in the assessment of human lung doses due to inhaled radioactivity because of the difficulty in making direct measurements. These models require information about the parameters of activity size distributions of thoron and radon progeny. The present study presents measured data on the attached and unattached activity size distributions of thoron and radon progeny in outdoor air in El-Minia, Egypt. The attached fraction was collected using a low-pressure Berner cascade impactor technique. A screen diffusion battery was used for collecting the unattached fraction. Most of the attached activities for 222Rn and 220Rn progeny were associated with aerosol particles of the accumulation mode. The activity size distribution of thoron progeny was found to be shifted to slightly smaller particle size compared to radon progeny.

14.
Onderstepoort J Vet Res ; 71(4): 319-26, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15732459

RESUMEN

In a cross sectional survey conducted during the period June 2001 to July 2002, the geographical distribution of ticks on cattle in the Sudan was determined. Seventeen locations were surveyed from Northern, Central, Eastern, Western, Blue Nile and White Nile Provinces. Total body collections of ticks were made from 20 cattle at each location. Four tick genera and 11 species were identified. The tick species collected included Amblyomma lepidum, Amblyomma variegatum, Boophilus decoloratus, Hyalomma anatolicum anatolicum, Hyalomma dromedarii, Hyalomma impeltatum, Hyalomma marginatum rufipes, Hyalomma truncatum, Rhipicephalus evertsi evertsi, Rhipicephalus sanguineus group and Rhipicephalus simus simus. Major ecological changes have occurred due to extensive animal movement, deforestation, desertification and establishment of large mechanized agricultural schemes. These factors have certainly affected the distribution of ticks and tick-borne diseases in the Sudan. The absence of A. variegatum and A. lepidum in northern Sudan was not surprising, since these tick species are known to survive in humid areas and not in the desert and semi-desert areas of northern Sudan. The absence of B. annulatus in northern and central Sudan is in accordance with the finding that this tick species is restricted to the southern parts of the central Sudan. The presence of H. anatolicum anatolicum in Um Benin in relatively high abundance is an interesting finding. The present finding may indicate that the southern limit of this species has changed and moved southwards to latitude 13 degrees N. It is concluded that major changes in tick distribution have taken place in the Sudan.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Ixodidae , Infestaciones por Garrapatas/veterinaria , Crianza de Animales Domésticos/métodos , Animales , Bovinos , Enfermedades de los Bovinos/parasitología , Clima , Estudios Transversales , Femenino , Interacciones Huésped-Parásitos , Ixodidae/clasificación , Masculino , Dinámica Poblacional , Estaciones del Año , Especificidad de la Especie , Sudán/epidemiología , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitología
15.
Appl Radiat Isot ; 49(7): 783-90, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9570097

RESUMEN

In this article the regional dose equivalent for exposure to 1 working level month (WLM), the annual effective dose equivalent and the dose equivalent conversion factor due to the inhalation of short-lived radon progeny (218Po, 214Pb and 214Bi/214Po) are calculated with a dosimetric model. Experimental results of aerosol size characteristics, unattached activity fractions, equilibrium factors, and activity size distributions of the short-lived radon progeny in indoor and outdoor atmosphere are summarized. Dose calculations based on these results show that the changes in dose rate values are influenced by the different model assumptions concerning deposition probabilities of aerosol particles in the respiratory system during inhalation, the sensitivity of different cells (epithelial, basal) to radiation and assuming nose or mouth breathing. The inverse relationship between the unattached fraction of potential alpha-particle energy in room air and the radioactive equilibrium between radon gas and its progeny indicates that dose equivalent is closely related to the concentration of radon gas averaged over a period of exposure.


Asunto(s)
Hijas del Radón , Radón/administración & dosificación , Sistema Respiratorio/efectos de la radiación , Administración por Inhalación , Adulto , Aerosoles , Calibración , Relación Dosis-Respuesta en la Radiación , Humanos , Pulmón/metabolismo , Pulmón/efectos de la radiación , Masculino , Tamaño de la Partícula , Dosis de Radiación , Radiometría , Radón/metabolismo , Sistema Respiratorio/metabolismo
16.
J Environ Radioact ; 77(3): 275-83, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15381321

RESUMEN

During a one year period, from Jan. 2002 up to Dec. 2002, approximately 130 air samples were analyzed to determine the atmospheric air activity concentrations of short- and long-lived (222Rn) decay products 214Pb and 210Pb. The samples were taken by using a single-filter technique and gamma-spectrometry was applied to determine the activity concentrations. A seasonal fluctuation in the concentration of 214Pb and 210Pb in surface air was observed. The activity concentrations of both radionuclides were observed to be relatively higher during the winter/autumn season than in spring/summer season. The mean activity concentration of 214Pb and 210Pb within the whole year was found to be 1.4+/-0.27 Bq m(-3) and 1.2+/-0.15 mBq m(-3), respectively. Different 210Pb:214Pb activity ratios during the year varied between 1.78 x 10(-4) and 1.6 x 10(-3) with a mean value of 8.9 x 10(-4) +/- 7.6 x 10(-5). From the ratio between the activity concentrations of the radon decay products 214Pb and 210Pb a mean residence time (MRT) of aerosol particles in the atmosphere of about 10.5+/-0.91 d could be estimated. The seasonal variation pattern shows relatively higher values of MRT in spring/summer season than in winter/autumn season. The MRT data together with relative humidity (RH), air temperature (T) and wind speed (WS), were used for a comprehensive regression analysis of its seasonal variation in the atmospheric air.


Asunto(s)
Aerosoles/química , Contaminantes Radiactivos del Aire/análisis , Atmósfera/química , Radioisótopos de Plomo/química , Radón/química , Egipto , Humedad , Radioisótopos de Plomo/análisis , Radón/análisis , Estaciones del Año , Temperatura , Viento
17.
Radiat Prot Dosimetry ; 95(1): 63-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11468809

RESUMEN

In addition to the workers in uranium mines, the staff of other underground mines, such as workers in underground phosphate mines, can be exposed to 222Rn and its progeny. In this study the individual radon progeny concentrations were measured in three Egyptian underground phosphate mines to estimate the occupational exposure of the workers at those sites. A filter method was used to measure individual radon progeny concentrations (218Po, 214Pb and 214Po). The reported mean values of radon progeny concentrations exceed the action levels which are recommended by ICRP 65 (1993). Based on the measured individual radon progeny concentrations (218Po, 214Pb and 214Po) in these mines, the annual effective dose for the workers has been calculated using the lung dose model of ICRP 66 (1994). According to the obtained results, some countermeasures were recommended in this study to minimise these exposure levels.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Minería/estadística & datos numéricos , Exposición Profesional/análisis , Monitoreo de Radiación/estadística & datos numéricos , Radón/análisis , Egipto , Humanos , Masculino , Fosfatos , Dosis de Radiación , Medición de Riesgo
19.
Arch Inst Pasteur Tunis ; 81(1-4): 31-4, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-16929763

RESUMEN

Ticks and tick-borne diseases are widespread in the Sudan, cause substantial economic losses and constitute major obstacles to the development of animal wealth. Most important among these diseases are tropical theileriosis, malignant ovine theileriosis, cowdriosis, babesiosis, anaplasmosis and avian spirochaetosis. However, knowledge about ticks and tick-borne diseases is still fragmentary and far from complete. The large number of tick species, the multplicity of transmitted agents and the diverse ecoclimatic zones of the Sudan provide a unique opportunity to host diverse research activities that could benefit other regions in Africa.


Asunto(s)
Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/veterinaria , Anaplasmosis/epidemiología , Animales , Babesiosis/epidemiología , Babesiosis/veterinaria , Enfermedades de las Aves/epidemiología , Aves , Bovinos , Enfermedades de los Bovinos/epidemiología , Clima , Costo de Enfermedad , Enfermedades de las Cabras/epidemiología , Cabras , Hidropericardio/epidemiología , Enfermedades de los Caballos/epidemiología , Caballos , Vigilancia de la Población , Prevalencia , Ovinos , Enfermedades de las Ovejas/epidemiología , Infecciones por Spirochaetales/epidemiología , Infecciones por Spirochaetales/veterinaria , Sudán/epidemiología , Theileriosis/epidemiología , Enfermedades por Picaduras de Garrapatas/transmisión
20.
ISRN Vet Sci ; 2014: 123904, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24977042

RESUMEN

A cross-sectional survey was carried out in ten states in Sudan to determine seroprevalence and to assess risk factors associated with Akabane virus (AKAV) infection in dairy herds. Serum samples were collected from a total of 361 dairy cattle and tested for antibodies against AKAV using ELISA. The prevalence rates of AKAV antibodies in cattle varied between 69.6% in Khartoum state and 3.3% in Sennar State with an overall prevalence rate of 29.4%. The prevalence rates of AKAV antibodies were significantly associated with breed being high in crossbred (39.9%; P < 0.001); female sex (33%; P < 0.001), and animals in the age group of 2-3 years old (45.3%; P < 0.001). Akabane virus antibodies prevalence was also highly associated with locality (P < 0.001); season being high in winter season (58.1%; P < 0.001); and animals raised under intensive management system (37%; P < 0.001). Among 68 cases suffering from reproductive (abortion and infertility) problems the prevalence rate of AKAV antibodies in animals with infertility problem (76.2%; P < 0.03) was significantly higher than in animals with abortion (48.9%). The study revealed that AKAV infection is highly prevalent in dairy cattle in Sudan and this calls for control strategy to be implemented.

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