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1.
BMC Public Health ; 20(1): 530, 2020 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-32306941

RESUMEN

BACKGROUND: Acute arboviral infections are distributed worldwide including Sudan, and dengue fever (DENV) is not an exception. The virus activity has recently been frequently reported in Kassala State, eastern Sudan. However, an appropriate epidemiological study would be necessary to provide accurate and precise estimates of the magnitude of recent DENV transmission in this area of endemicity. METHODS: In the present investigation, a cross sectional study was conducted to advance beyond the current knowledge of the epidemiology of the disease in Kassala State. The prevalence of the disease was estimated and associated risk factors were determined. Sampled sera were collected and screened for recent dengue transmissionas as determined by DENV-IgM enzyme-linked immunosorbent assay (ELISA). The collection of data for risk assessment was supported by a well designed structured questionnaire. RESULTS: The prevalence of recent DENV infection was estimated to be (11.42%). Potential risk factors to DENV seropsitivity include, age (OR = 3.24, CI = 1.81-5.77,p-value = 0.001); low income (OR = 3.75, CI = 1.57-8.93, p-value = 0.027); mosquito control (OR = 4.18, CI = 2.33-7.51, p-value = 0.004); and localities. CONCLUSION: The present study showed a high rate of circulating DENV IgM antibodies among the participants of the study (11.42%), suggesting recent transmission of DENV in Kassala State, eastern Sudan. The frequent occurrence of DENV infections necessitates the need for improved surveillance programs and prevention measures to combat this important arboviral disease in Sudan.


Asunto(s)
Anticuerpos Antivirales/sangre , Virus del Dengue/inmunología , Dengue/epidemiología , Enfermedades Endémicas/estadística & datos numéricos , Inmunoglobulina M/sangre , Adolescente , Adulto , Estudios Transversales , Dengue/inmunología , Dengue/transmisión , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulina M/inmunología , Masculino , Persona de Mediana Edad , Control de Mosquitos/estadística & datos numéricos , Pobreza/estadística & datos numéricos , Prevalencia , Medición de Riesgo , Factores de Riesgo , Estudios Seroepidemiológicos , Sudán/epidemiología , Adulto Joven
2.
BMC Vet Res ; 14(1): 230, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-30068335

RESUMEN

BACKGROUND: African horse sickness virus (AHSV) is an infectious non contagious insect-transmitted double-stranded (ds) RNA orbivirus of the family Reoviridae. AHSV causes an often fatal hemorrhagic infection with high mortality among selected breeds of Arabian horses. This study was conducted to avail some information with regard to the prevalence and associated risk factors of AHSV among ecotype breeds of horses in central Sudan. METHODS: Sera were collected from 320 horses, which were selected randomly from four localities and employed in the study. A competitive enzyme-linked immunosorbent assay (cELISA) was used to screen sampled sera for AHSV-specific immunoglobulin G (Ig G) antibodies. RESULTS: Seropositivity to AHSV Ig G was detected in 275 out of the 320 horse sera, thus accounting for a prevalence rate of 85.9%. Potential risk factors to AHSV infection were reported to be associated with horse breed (OR = 5.0, CI = 0.07-2.104, p-value = 0.039) and activity of the horse (OR = 3.21, CI = 0.72-1.48, p- value = 0.008). CONCLUSIONS: The high prevalence of AHSV in Khartoum State of Central Sudan necessitates the need for continuous surveillance for AHSV infection to prevent a possible disease outbreak in this region of the African continent.


Asunto(s)
Virus de la Enfermedad Equina Africana , Enfermedad Equina Africana/epidemiología , Enfermedad Equina Africana/etiología , Enfermedad Equina Africana/virología , Animales , Anticuerpos Antibacterianos/inmunología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Caballos/virología , Inmunoglobulina G/inmunología , Masculino , Prevalencia , Factores de Riesgo , Estudios Seroepidemiológicos , Sudán/epidemiología , Encuestas y Cuestionarios
3.
BMC Public Health ; 18(1): 921, 2018 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-30053811

RESUMEN

BACKGROUND: Dengue fever, caused by dengue virus (DENV), has become one of the most important mosquito-borne viral diseases with a steady rise in global incidence, including the Sudan. Sporadic cases and frequent acute febrile illness outbreaks, compatible with Dengue fever, have been reported in El-Gadarif State, Sudan. However, diagnosis was based almost exclusively on clinical signs without confirmatory laboratory investigations. Despite the magnitude of the problem in El-Gadarif State, no information is currently available with regard to the epidemiology of the disease in this State. El-Gadarif State is one of the largest commercial centers in the Sudan. The objective of the present investigation is to estimate the prevalence of DENV antibodies, and determine the potential risk factors associated with seropositivity among residents of El-Gadarif State. METHODS: A cross sectional study was conducted in a total of 701residents randomly selected from all 10 localities in El-Gadarif State. The sera from the 701 residents were tested for the presence of DENV-specific immunoglobulin G (IgG) antibodies using a commercially available Anti-dengue IgG enzyme-linked immunosorbent assay (ELISA). RESULTS: Among the 701 residents, 334 residents (47.6%) were seropositive for DENV. Mosquito control (OR = 2.73, CI = 1.37-5.87, p-value = 0.001); low income (OR = 2.31, CI: 1.71-6.36, p value = 0.032); sleeping out-doors (OR = 3.73, CI = 2.63-6.23, p-value = 0.013), and localities were determined as potential risk factors for contracting DENV infection. CONCLUSIONS: The prevalence rate of DENV antibodies among residents of El-Gadarif State is significantly high (47.6%). Further epidemiologic studies including, distribution of mosquito vectors and implementation of improved surveillance are urgently warranted for better prediction and prevention of a possible DENV outbreak in El-Gadarif State, Sudan.


Asunto(s)
Anticuerpos Antivirales/sangre , Virus del Dengue/inmunología , Dengue/epidemiología , Control de Mosquitos/estadística & datos numéricos , Anciano , Animales , Preescolar , Estudios Transversales , Dengue/sangre , Brotes de Enfermedades/prevención & control , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pobreza/estadística & datos numéricos , Prevalencia , Factores de Riesgo , Pruebas Serológicas , Sudán/epidemiología
5.
Virol J ; 14(1): 147, 2017 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-28774342

RESUMEN

BACKGROUND: Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne viral zoonotic disease caused by Crimean-Congo hemorrhagic fever virus (CCHFV), a member of the genus Nairovirus in the family Bunyaviridae. CCHF is typically asymptomatic in animals but can be highly fatal in humans approaching case fatality rate of approximately 30%. In the present investigation, a cross sectional study was conducted to determine the prevalence of CCHF and to identify the potential risk factors associated with CCHFV seropositivity among the one-humped camel (Camelus dromedaries) in Central Sudan. METHODS: A total of 361 camels selected randomly from six localities were employed in the study. Sera sampled were tested for the presence of CCHFV-specific immunoglobulin G (IgG) antibodies using enzyme-linked immunosorbent assay (ELISA). RESULTS: CCHFV seropositivity was recorded in 77 out of 361 animals accounting for a prevalence rate of 21.3%. Age (OR = 3.6, CI = 1.72-7.79, p-value = 0.026); locality (OR = 5.85, CI = 1.81-18.83, p- value = 0.003), tick number (OR = 4.6, CI = 1.37-9.81, P-value 0.04); tick control (OR = 2.2, CI, 1.11-4.35, P-value = 0.023) and breed (OR = 6.60, CI = 2.38-18.36, P-value = 0.001) were recorded as potential risk factors for contracting CCHF. CONCLUSIONS: The prevalence of CCHF is significantly high among camels in Khartoum State, Sudan. Age, breed, locality and tick control are considered as potential risk factors for contracting CCHF. This study would be expected to reduce the impact on the livelihood of pastoral communities and ultimately avoid disease spread in human.


Asunto(s)
Anticuerpos Antivirales/sangre , Camelus/virología , Virus de la Fiebre Hemorrágica de Crimea-Congo/inmunología , Fiebre Hemorrágica de Crimea/veterinaria , Animales , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Femenino , Fiebre Hemorrágica de Crimea/epidemiología , Fiebre Hemorrágica de Crimea/virología , Inmunoglobulina G/sangre , Masculino , Factores de Riesgo , Estudios Seroepidemiológicos , Sudán/epidemiología
6.
N Engl J Med ; 368(21): 1992-2003, 2013 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-23656588

RESUMEN

BACKGROUND: The combination of ataxia and hypogonadism was first described more than a century ago, but its genetic basis has remained elusive. METHODS: We performed whole-exome sequencing in a patient with ataxia and hypogonadotropic hypogonadism, followed by targeted sequencing of candidate genes in similarly affected patients. Neurologic and reproductive endocrine phenotypes were characterized in detail. The effects of sequence variants and the presence of an epistatic interaction were tested in a zebrafish model. RESULTS: Digenic homozygous mutations in RNF216 and OTUD4, which encode a ubiquitin E3 ligase and a deubiquitinase, respectively, were found in three affected siblings in a consanguineous family. Additional screening identified compound heterozygous truncating mutations in RNF216 in an unrelated patient and single heterozygous deleterious mutations in four other patients. Knockdown of rnf216 or otud4 in zebrafish embryos induced defects in the eye, optic tectum, and cerebellum; combinatorial suppression of both genes exacerbated these phenotypes, which were rescued by nonmutant, but not mutant, human RNF216 or OTUD4 messenger RNA. All patients had progressive ataxia and dementia. Neuronal loss was observed in cerebellar pathways and the hippocampus; surviving hippocampal neurons contained ubiquitin-immunoreactive intranuclear inclusions. Defects were detected at the hypothalamic and pituitary levels of the reproductive endocrine axis. CONCLUSIONS: The syndrome of hypogonadotropic hypogonadism, ataxia, and dementia can be caused by inactivating mutations in RNF216 or by the combination of mutations in RNF216 and OTUD4. These findings link disordered ubiquitination to neurodegeneration and reproductive dysfunction and highlight the power of whole-exome sequencing in combination with functional studies to unveil genetic interactions that cause disease. (Funded by the National Institutes of Health and others.).


Asunto(s)
Ataxia/genética , Demencia/genética , Hipogonadismo/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación , Animales , Consanguinidad , Exoma , Femenino , Humanos , Masculino , Linaje , Ubiquitina-Proteína Ligasas/metabolismo , Pez Cebra
7.
Ir Vet J ; 69: 6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-27293548

RESUMEN

BACKGROUND: Rift valley fever (RVF) is a mosquito-borne viral disease of domestic livestock and wild ruminants. In camels RVF may cause abortion among pregnant camels, but is most often asymptomatic among other camels. In this study, a seroepidemiological survey was conducted to determine the prevalence of RVFV antibodies and to identify the potential risk factors associated with RVFV seropositivity among the Sudanese one-humped camel (Camelus dromedaries) in Khartoum State, Sudan. A cross sectional study was conducted in Khartoum State, Sudan, in a total of 240 camels selected randomly from four localities. Sera sampled were tested for the presence of RVFV-specific immunoglobulin G (IgG) antibodies using a competitive enzyme-linked immunosorbent assay (c-ELISA). RESULTS: RVFV seropositivity was recorded in 23 out of 240 animals, prevalence rate of 9.6 % among camels in Khartoum State. Age (OR = 8.29, p-value = 0.04) and heavy rainfall (OR = 5.36, p value = 0.01) were recorded as potential risk factors for contracting RVF. CONCLUSIONS: Older age and heavy rainfall were considered as potential risk factors for seropositivity to RVF. Surveillance for RVF among camels and distribution of mosquito vectors should continue to better understand the clinical signs associated with RVFV infection in camels and provide public health authorities an opportunity to anticipate and prepare for a possible RVF outbreak in Khartoum State, Sudan.

8.
BMC Vet Res ; 10: 94, 2014 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-24762138

RESUMEN

BACKGROUND: Bluetongue virus causes febrile disease in sheep and a fatal hemorrhagic infection in North American White-tailed deer. However, in cattle the disease is typically asymptomatic and no clinical overt disease is associated with bluetongue infection. Bluetongue virus activity has been detected in Khartoum, Sennar and South Darfur states of the Sudan. Currently, no information is available in regard to previous exposure of livestock to Bluetongue virus in North Kordufan State, the largest livestock producing region in the country. The present study was conducted to determine the prevalence of bluetongue antibodies and to identify the potential risk factors associated with the presence of bluetongue antibodies among cattle in North Kordufan State, Sudan. A total of 299 bovine blood samples were collected randomly from six localities in North Kordufan State and were tested by enzyme-linked immunosorbent assay (ELISA) for detection of BTV-specific immunoglobulin G (IgG) antibodies. RESULTS: The serological evidence of Bluetongue virus infection was observed in 58 out of 299 cows, accounting for a 19.4% prevalence rate among cattle in North Kordufan State. Older cattle (>2 years of age) had four times the odds to be infected with BTV compared to young cattle (OR = 4.309, CI = 1.941-9.567, p-value = 0.01). Application of preventive measures, such as spraying or dipping with insecticide protects cattle against Bluetongue infection. Application of vector control measures decreased the odds for bluetongue seropositivity by 7 times (OR = 7.408, CI = 3.111-17.637, p-value = 0.01). CONCLUSIONS: The results of this study indicated that age and application of routine insecticides are influential risk factors for seroprevalence of Bluetongue in cattle. Surveillance of Bluetongue virus should be extended to include other susceptible animals and to study the distribution of the insect vectors in the region to better predict and respond to BTV outbreak in the State of North Kordufan, Sudan.


Asunto(s)
Virus de la Lengua Azul , Lengua Azul/epidemiología , Enfermedades de los Bovinos/virología , Animales , Lengua Azul/prevención & control , Bovinos , Enfermedades de los Bovinos/epidemiología , Estudios Transversales , Control de Insectos/métodos , Insectos Vectores/efectos de los fármacos , Insecticidas/farmacología , Oportunidad Relativa , Factores de Riesgo , Pruebas Serológicas , Sudán/epidemiología
9.
Ir Vet J ; 67(1): 4, 2014 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-24507448

RESUMEN

BACKGROUND: Bluetongue virus (BTV) is an insect-transmitted virus, which causes bluetongue disease (BT) in sheep and a fatal hemorrhagic infection in North American white-tailed deer. However, in cattle the disease is typically asymptomatic and no overt clinical signs of disease appear to be associated with BTV infection. Serological evidence and isolation of different BTV serotypes have been reported in Sudan, however, no information is currently available in regard to previous exposure of Sudanese livestock to BTV infection in East Darfur State, Sudan. AIMS: To determine the prevalence of BTV antibodies and to identify the potential risk factors associated with BTV infection among cattle in East Darfur State, Sudan. METHODS: A total of 224 blood samples were collected randomly from five localities in East Darfur State, Sudan. The serum samples were screened for detection of BTV-specific immunoglobulin G (IgG) antibodies using a competitive enzyme-linked immunosorbent assay (c-ELISA). RESULTS: Serological evidence of BTV infection was observed in 150 out of 224 animals accounting for a 67% prevalence rate among cattle in East Darfur State. Older cattle (>2 years of age) were six times more likely to be infected with BTV (OR = 6.62, CI = 2.87-15.26, p-value = 0.01). Regarding animal source (contact with other herds) as a risk factor, it was shown that cattle purchased from market or introduced from other herds were 3 times at higher risk of being infected with BTV (OR = 3.87, CI = 1.07-13.87, p value = 0.03). Exposure of cattle to the insect vector increased the risk of contracting BTV infection by six times compared to non-exposed cattle (OR = 6.44, CI = 1.53-27.08, p value = 0.01). CONCLUSION: The present study indicated that age, animal source and the intensity of the insect vector are influential risk factors for BTV infection in cattle in the Darfur region. Surveillance for BTV infection should be extended to include other susceptible ruminants and to study the distribution of the insect vectors to better predict and respond to a possible BTV outbreak in the State of East Darfur, Sudan.

10.
Heliyon ; 10(4): e26459, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38434077

RESUMEN

The Belt and Road Initiative (BRI) is one such comprehensive plan that aims to boost economic growth and connectivity across Africa, Asia, and Europe. While the effort may be good for boosting exports and foreign direct investment (FDI), some are worried about the toll it may take on the environment. Therefore, we aim to examine the effect of international trade and FDI on the ecological footprint in BRI countries, considering the mediating role of the environmental performance index. The CCEMG estimator was used to examine the impacts of imports, exports, FDI, population growth, urbanization, and the Environmental Performance Index (EPI) on the global ecological footprint. Our findings show that export has a positive relationship with ecological footprint. Similarly, imports and FDI revealed a positive association with the ecological footprint. Finally, environmental performance revealed a negative association with ecological footprint in BRI countries. Our findings support the pollution haven theory by demonstrating the critical importance of environmental regulations in enticing responsible investors. By using the ecological footprint as an all-encompassing measure of environmental effect, this study sheds light on the need to incorporate sustainability within the goals of the BRI. This research emphasizes the importance of adopting well-informed methods to promote sustainable development and mitigate the BRI's adverse environmental impacts.

11.
Heliyon ; 10(5): e26672, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38444460

RESUMEN

This study examines the impact of financing decisions and ownership structure on green accounting disclosure (GAD) in developing economies, where sustainability practices have not been extensively integrated into business models. We conducted empirical analysis considering 172 manufacturing companies from 2001 to 2022, utilizing both fixed effect and random effect estimation techniques. The findings revealed that firms that rely primarily on debt financing tend to have an inverse relationship with the levels of green accounting disclosure. However, firms that depend mainly on equity financing tend to have higher levels of green accounting disclosure. In addition, the results of the estimation analysis showed a favorable association between ownership concentration and disclosure of green accounting practices. The findings suggest that policymakers should consider incentivizing firms to prioritize equity financing over debt financing to promote higher levels of green accounting disclosure. Additionally, policies should aim at encouraging ownership concentration within firms to enhance the transparency and accountability of environmental reporting practices, ultimately advancing the achievement of Sustainable Development Goals 12 and 13.

12.
Virol J ; 10: 178, 2013 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-23738961

RESUMEN

BACKGROUND: Crimean Congo hemorrhagic fever (CCHF), caused by CCHF virus (CCFV), may cause a fatal hemorrhagic illness in humans with mortality rate of approximately 30%. However, in animals the disease is typically asymptomatic and no clinical hemorrhagic infections appears to be associated with CCHFV. Recently, CCHF activity has been detected in western and southern Kordufan region, Sudan. Currently, no information is available in regard to previous exposure of livestock to CCHFV infection in the region. AIMS: In the present study, a seroepidemiological survey was conducted to determine the prevalence of CCHF and to identify the potential risk factors associated with the disease among cattle in North Kordufan State, Sudan. METHODS: In this survey, 299 blood samples were collected randomly from six localities in North Kordufan State and were tested by enzyme-linked immunosorbent assay (ELISA) for detection of CCHFV-specific immunoglobulin G (IgG) antibodies. RESULTS: The result of the study indicated that the prevalence rate of CCHF was relatively high among cattle, where serological evidence of the infection was observed in 21 (7.0%) of 299 animals. Older cattle were eight times more likely to be infected with the virus (OR=8.0824, CI=1.174-66.317, p-value=0.034). Cross breeds were at 37 time higher at risk compared to endogenous breed (OR=37.06, CI=1.455-944, p-value=0.029). Highly tick-infested cattle are 6 times higher at risk for CCHF when compared to tick-free animals (OR=6.532, CI=1.042-10.852, p-value=0.030). CONCLUSION: It is recommended that surveillance of CCHF should be extended to include other ruminant animals and to study the distribution of ticks in the region to better predict and respond to CCHF outbreak in the State of North Kordufan, Sudan.


Asunto(s)
Anticuerpos Antivirales/sangre , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/virología , Virus de la Fiebre Hemorrágica de Crimea-Congo/inmunología , Fiebre Hemorrágica de Crimea/veterinaria , Animales , Bovinos , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Fiebre Hemorrágica de Crimea/epidemiología , Fiebre Hemorrágica de Crimea/virología , Inmunoglobulina G/sangre , Estudios Seroepidemiológicos , Sudán/epidemiología
13.
Nat Prod Res ; 37(15): 2473-2479, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35275503

RESUMEN

Six 5(14)-membered ring type of cyclopeptide alkaloids (CPAs), including two undescribed members, 1-hydro,2ß-methoxy-mauritine-A (1) and 1-hydro,2α-methoxy-mauritine-A (2), together with four known compounds, mauritine-A (3), mauritine C (4), amphibine-A (5), and amphibine-E (6), were isolated from the root bark of Ziziphus spina-christi (L.) Desf., Their structures were determined by multiple spectral analyses, including UV, IR, 1D NMR, 2D NMR, EI-MS, HR-EI-MS, FAB-MS and ESI-MS, and by comparison with literature. All six CPAs were tested in vitro for cytotoxicity by three human cancer cell lines (MCF7, H460 and Hela) and a human normal cell line (BJ). None of the compounds showed cytotoxicity towards all tested cell lines.


Asunto(s)
Alcaloides , Ziziphus , Humanos , Péptidos Cíclicos/farmacología , Péptidos Cíclicos/química , Ziziphus/química , Corteza de la Planta/química , Alcaloides/química , Células HeLa
14.
Transplantation ; 107(11): 2353-2363, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37871273

RESUMEN

BACKGROUND: "Natural" ABO antibodies (Abs) are produced without known exposure to A/B carbohydrate antigens, posing significant risks for hyperacute rejection during ABO-incompatible transplantation. We investigated anti-A "natural" ABO antibodies versus intentionally induced Abs with regard to the need for T-cell help, the impact of sex, and stimulation by the microbiome. METHODS: Anti-A was measured by hemagglutination assay of sera from untreated C57BL/6 wild-type (WT) or T cell-deficient mice of both sexes. Human ABO-A reagent blood cell membranes were injected intraperitoneally to induce anti-A Abs. The gut microbiome was eliminated by maintenance of mice in germ-free housing. RESULTS: Compared with WT mice, CD4 + T-cell knockout (KO), major histocompability complex-II KO, and αß/γδ T-cell receptor KO mice produced much higher levels of anti-A nAbs; females produced dramatically more anti-A nAbs than males, rising substantially with puberty. Sensitization with human ABO-A reagent blood cell membranes did not induce additional anti-A in KO mice, unlike WT. Sex-matched CD4 + T-cell transfer significantly suppressed anti-A nAbs in KO mice and rendered mice responsive to A-sensitization. Even under germ-free conditions, WT mice of several strains produced anti-A nAbs, with significantly higher anti-A nAbs levels in females than males. CONCLUSIONS: Anti-A nAbs were produced without T-cell help, without microbiome stimulation, in a sex- and age-dependent manner, suggestive of a role for sex hormones in regulating anti-A nAbs. Although CD4 + T cells were not required for anti-A nAbs, our findings indicate that T cells regulate anti-A nAb production. In contrast to anti-A nAbs, induced anti-A production was T-cell dependent without a sex bias.


Asunto(s)
Formación de Anticuerpos , Microbiota , Masculino , Femenino , Ratones , Animales , Humanos , Ratones Endogámicos C57BL , Anticuerpos , Linfocitos T CD4-Positivos , Ratones Noqueados
15.
Environ Sci Pollut Res Int ; 29(35): 52818-52832, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35274204

RESUMEN

This paper investigates the short-term dynamics as well as the long-term relationship between natural gas consumption and economic growth in Nigeria, taking breaks into account. The techniques employed include Shahbaz-Omay-Roubaud unit root test with sharp and smooth breaks and autoregressive distributed lag (ARDL) model with breaks. The results revealed that natural gas consumption is positively related to growth both in the short-term and long-term but only significant in the latter. However, there is evidence of bidirectional causality in the long-term and unidirectional causality in the short-term, from growth to natural gas consumption. The implication of the findings is that natural gas is a contributing factor to the growth of the Nigerian economy, and any energy policy aimed at increasing the consumption of natural gas could lead to the increase in economic growth and that Nigerian authorities could adopt energy conservation policies in the short-term so as to take the issue of global warming into consideration. Therefore, the paper recommends stepping up efforts to increase natural gas consumption by building more gas storage facilities, pipeline installations, exploring alternative energy sources, raising awareness/enlightenment about the uses of natural gas, suitability in its use, economic and environmental benefits of its use, ensuring its affordable availability, and beeping up security against pipelines vandalization. Moreover, in the short-term, the country could enact energy conservation policies to combat global warming.


Asunto(s)
Desarrollo Económico , Gas Natural , Dióxido de Carbono/análisis , Fuentes Generadoras de Energía , Nigeria
16.
Artículo en Inglés | MEDLINE | ID: mdl-36714678

RESUMEN

In this paper, we explore local dynamics with topological classifications, bifurcation analysis, and chaos control in a discrete-time COVID-19 epidemic model in the interior of ℝ + 4 . It is explored that for all involved parametric values, discrete-time COVID-19 epidemic model has boundary equilibrium solution and also it has an interior equilibrium solution under definite parametric condition. We have explored the local dynamics with topological classifications about boundary and interior equilibrium solutions of the discrete-time COVID-19 epidemic model by linear stability theory. Further, for the discrete-time COVID-19 epidemic model, existence of periodic points and convergence rate are also investigated. It is also studied the existence of possible bifurcations about boundary and interior equilibrium solutions and proved that there exists no flip bifurcation about boundary equilibrium solution. Moreover, it is proved that about interior equilibrium solution, there exist Hopf and flip bifurcations, and we have studied these bifurcations by utilizing explicit criterion. Moreover, by feedback control strategy, chaos in the discrete COVID-19 epidemic model is also explored. Finally, theoretical results are verified numerically.

17.
Int J Surg Case Rep ; 97: 107433, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35878551

RESUMEN

BACKGROUND: The presence of ectopic thyroid tissue is a developmental disorder that affects about one per 100,000-300,000 people. It is extraordinarily rare for ectopic thyroid to be out of the lines of its descent. This case is the first to report a cancerous ectopic thyroid in the mandibular bone with a goitrous orthotopic thyroid gland. CASE PRESENTATION: 80-year-old female of free medical background presented to our clinic with painless left mandibular swelling that recent increase in size after tooth extraction. Surprisingly the diagnosis of ectopic thyroid tissue with cancerous follicular cells was reached upon histological analysis. The goitrous thyroid gland was found in its expected cervical location, and the patient was euthyroid. CONCLUSION: Because this diagnosis extremely rare, the possibility of ectopic thyroid carcinoma in cases of a pathological mass in the mandible must always be carefully thought out. A high degree of suspicion is essential as the unusual presentation could take.

18.
Int Health ; 13(4): 327-333, 2021 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-32949463

RESUMEN

BACKGROUND: Hydatid disease or cystic echinococcosis (CE) is caused by the larval stages of the cestode parasite Echinococcus granulosus. The objectives of this study were to estimate the prevalence of seropositivity and to identify the risk factors associated with the disease among humans in Khartoum State, Central Sudan. METHODS: A cross-sectional study was conducted between November 2017 and April 2018. A total of 305 randomly selected consenting participants from three localities were included in the current investigation using a multistage probability sampling method. An in-house enzyme-linked immunosorbent assay was used to detect immunoglobulin G antibodies to E. granulosus. The χ2 test and logistic regression analysis were used to determine the risk factors associated with CE seropositivity. RESULTS: A seroprevalence of 6.5% (20/305) was recorded among humans in Khartoum State, Central Sudan. Age (odds ratio [OR] 16.61 [confidence interval {CI} 2.21 to 117.92], p=0.006), locality (OR 3.08 [CI 1.42 to 22.54], p=0.011) and contact with dogs (OR 2.34 [CI 0.026 to 0.646], p=0.013) were recorded as potential risk factors for seropositivity to CE in the study area. CONCLUSIONS: The seroprevalence of CE (6.5%) is high among humans in Khartoum State, Central Sudan. Improved surveillance is necessary to optimize control and prevention strategies for CE as an important neglected zoonotic disease among the human population in the study area of Central Sudan.


Asunto(s)
Equinococosis , Animales , Estudios Transversales , Perros , Equinococosis/epidemiología , Humanos , Prevalencia , Factores de Riesgo , Estudios Seroepidemiológicos , Sudán/epidemiología
19.
Environ Sci Pollut Res Int ; 25(28): 28500-28516, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30088249

RESUMEN

The present work analyzes the effect of antioxidants on engine combustion performance of a multi-cylinder diesel engine fueled with PB30 and PB50 (30 and 50 vol.% palm biodiesel (PB)). Four antioxidants namely N,N'-diphenyl-1,4-phenylenediamine (DPPD), N-phenyl-1,4-phenylenediamine (NPPD), 2(3)-tert-Butyl-4-methoxyphenol (BHA), and 2-tert-butylbenzene-1,4-diol (TBHQ) were added at concentrations of 1000 and 2000 ppm to PB30 and PB50. TBHQ showed the highest activity in increasing oxidation stability in both PB30 and PB50 followed by BHA, DPPD, and NPPD respectively, without any negative effect on physical properties. Compared to diesel fuel, PB blends showed 4.61-6.45% lower brake power (BP), 5.90-8.69% higher brake specific fuel consumption (BSFC), 9.64-11.43% higher maximum in cylinder pressure, and 7.76-12.51% higher NO emissions. Carbon monoxide (CO), hydrocarbon (HC), and smoke opacity were reduced by 36.78-43.56%, 44.12-58.21%, and 42.59-63.94%, respectively, than diesel fuel. The start of combustion angles (SOC) of PB blends was - 13.2 to - 15.6 °CA BTDC, but the combustion delays were 5.4-7.8 °CA short compared to diesel fuel which were - 10 °CA BTDC and 11°CA respectively. Antioxidant fuels of PB showed higher BP (1.81-5.32%), CO (8.41-24.60%), and HC (13.51-37.35%) with lower BSFC (1.67-7.68%), NO (4.32-11.53%), maximum in cylinder pressure (2.33-4.91%) and peak heat release rates (HRR) (3.25-11.41%) than baseline fuel of PB. Similar SOC of - 13 to - 14 °CA BTDC was observed for PB blended fuels and antioxidants. It can be concluded that antioxidants' addition is effective in increasing the oxidation stability and in controlling the NOx emissions of palm biodiesel fuelled diesel engine.


Asunto(s)
Antioxidantes/química , Biocombustibles/análisis , Gasolina/análisis , Vehículos a Motor/normas , Óxidos de Nitrógeno/análisis , Emisiones de Vehículos/análisis , Monóxido de Carbono/análisis , Hidrocarburos/análisis , Oxidación-Reducción , Humo/análisis
20.
J Photochem Photobiol B ; 182: 62-70, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29621690

RESUMEN

The eco-friendly biosynthesis of silver nanoparticles (AgNps) from bark extract of Albizia chevalier are reported here for their anti-proliferative, antibacterial and pollutant degradation potentials. The synthesized AgNps were characterized by FTIR spectroscopy, transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), energy dispersive X-rays spectrometry (EDS) and X-ray diffraction studies. The TEM and FESEM images show a monodispersed spherical shaped particles of approximately 30 nm. Crystalline peaks were obtained for the synthesized AgNps in XRD spectrum. The AgNps were investigated for in vitro anticancer and antibacterial activities and its potential to degrade 4-nitrophenol (4-NP) and congo red dye (CR). The MTT results shows a significant dose-dependent antiproliferation effect of the AgNps on the cell lines HepG2, MDA-MB-231 and MFC7. The effect was found more pronounced in MDA-MB-231 as compared to MFC-7 cell lines. The antibacterial results indicated 99 and 95% killing of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) respectively, after 24 h of incubation with the AgNps. The AgNps were found to speed up the reductive degradation of 4-NP and CR dye, which give an alternative route for the removal of toxic organic pollutants from the wastewater. The synthesized AgNps were not only used as a bactericidal and anticancer agent, but also effectively used for the reductive degradation of carcinogenic compounds which are listed as the priority pollutants. Therefore, AgNps have the potential for the treatment of various cancers, bacterial infections and for industrial detoxification of wastewater.


Asunto(s)
Albizzia/química , Rojo Congo/química , Nanopartículas del Metal/química , Nitrofenoles/química , Extractos Vegetales/farmacología , Plata/química , Plata/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Humanos , Microscopía Electrónica de Transmisión , Oxidación-Reducción , Corteza de la Planta/química , Extractos Vegetales/química , Contaminantes Químicos del Agua/química
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