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1.
MethodsX ; 11: 102348, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37693658

RESUMO

The hydraulic and integrated modeling approaches appear to stand out in the sequence of flood risk models that have been presented because of their predictive accuracy. The former has a high probability of under predicting and the latter has a high tendency to over-predict. This study proposed a methodological approach that combines the hydraulic and integrated models using analytical hierarchical raster fusion techniques to strengthen the weaknesses of the individual models. This study seeks to undertake a flood inundation model, a runoff model, and raster fusion models using GIS and HEC-RAS rain-on-grid methods to map flood risk in the Ona river basin of Ibadan city. •A hydraulic model was used to identify flood depth and inundation areas along a major stream channel, which was then extracted, rasterized, resampled, and reclassified to a spatial resolution of 5 m.•Several raster datasets (indicators) were created from land use, elevation, soil, and geological data layers using advanced GIS techniques.•AHP assisted raster data fusion model was used to combine all of the raster indicators into a single consolidated hybrid flood raster layer that revealed flood risk areas by magnitude.

2.
J Reprod Med ; 62(3-4): 204-6, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30230796

RESUMO

Background: Sarcoidosis is a multisystem inflammatory disease of unknown etiology. It is uncommon, with an incidence of approximately 16.5 per 100,000 men.1 It is characterized by noncaseating epithelioid granulomata that typically affect the chest, skin, eyes, and, much less commonly, the genital system (<0.2% of cases). Sarcoidosis can affect any of the scrotal structures, although due to its rarity, investigation of solid masses of the testes are largely targeted towards excluding either a malignant or infective etiology.² Case: We report a rare case of a 27-year-old male who presented with bilateral testicular and neck swellings. He underwent orchidectomy, and histopathology demonstrated sarcoidosis. He subsequently developed both pituitary and testicular sarcoidosis resulting in azoospermia. Through the administration of gonadotropins and surgical sperm retrieval we were able to retrieve sperm suitable for assisted reproductive technologies. Conclusion: This case illustrates the difficulties faced in managing the fertility of men who develop systemic sarcoidosis. It also highlights the diagnostic and therapeutic challenges faced by physicians when presented with a case of systemic sarcoidosis.


Assuntos
Sarcoidose/diagnóstico , Sarcoidose/terapia , Recuperação Espermática , Doenças Testiculares/diagnóstico , Doenças Testiculares/terapia , Adulto , Azoospermia/etiologia , Gonadotropinas/uso terapêutico , Humanos , Masculino , Sarcoidose/complicações , Doenças Testiculares/complicações , Testículo/patologia
3.
Reprod Biomed Online ; 22(2): 215-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21227754

RESUMO

The long-held view that diabetes has little effect on male reproductive function has been challenged by findings that the condition influences fertility in numerous previously undetected ways. This retrospective chart review of 3000 couples determined the incidence of couples with a male diabetic seeking assisted reproduction treatment and assessed any relationship between male diabetes and IVF/intracytoplasmic sperm injection (ICSI) outcome. Eight (2.7%) couples were found with a diabetic male partner, of which 18 couples underwent assisted reproduction treatment (five IVF, 12 ICSI, one both), with fertilization rates (IVF 68%, ICSI 62%) similar to non-diabetic patients (IVF 70%, ICSI 71%) and no difference in embryo quality. Two men had retrograde ejaculation and two were azoospermic. Other than reduced sperm motility, the remaining 14 had normal World Health Organization semen parameters. Embryo transfers produced one pregnancy (5% combined IVF/ICSI pregnancy rate/cycle) giving a lower-than-expected rate (28.8%). The pregnancy rate from seven FETs (29%) was comparable to the expected (21.3%). Compared with non-diabetics, approximately three times more couples with diabetic men sought treatment, with a larger percentage having 'unexplained' infertility. Fertilization rates and embryo quality did not differ but pregnancy rates were lower in couples with a diabetic male.


Assuntos
Complicações do Diabetes/terapia , Fertilização in vitro , Infertilidade Masculina/terapia , Complicações do Diabetes/epidemiologia , Feminino , Humanos , Infertilidade Masculina/complicações , Masculino , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Resultado do Tratamento
4.
Fertil Steril ; 92(6): 2085-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19589518

RESUMO

Routine semen analysis found no differences in diabetic men; however, mRNA profiles showed changes in the expression of genes involved in oxidative stress.


Assuntos
Diabetes Mellitus Tipo 1/genética , Perfilação da Expressão Gênica , Infertilidade Masculina/genética , Estresse Oxidativo/genética , Espermatogênese/genética , Fertilidade/genética , Humanos , Masculino , RNA Mensageiro/metabolismo , Espermatozoides/fisiologia
5.
Syst Biol Reprod Med ; 54(3): 111-25, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18570047

RESUMO

Male infertility has traditionally been diagnosed by microscopic assessment of concentration, motility and morphology of sperm in the ejaculate. Most laboratories use sperm isolated by various methods such as density gradient centrifugation to enrich for subpopulations of sperm believed to have greater fertilization potential. These tests are essential to provide the fundamental information on which clinicians base their initial diagnosis. However, in the clinical setting, tests with superior prognostic value are needed. Tests showing much promise are those determining sperm DNA integrity, particularly the Comet, TUNEL, and Sperm Chromatin Structure assays. Sperm nuclear DNA fragmentation has been positively correlated with lower fertilization rates in IVF, impaired implantation rates, an increased incidence of abortion and disease in offspring, including childhood cancer. The mitochondrial genome of sperm has also been shown to be a sensitive marker of sperm health. Although the usefulness of these tests is recognized, insufficient resources have been available to develop standardized tests and protocols that could lead to universally accepted clinical thresholds. Associated with the lack of useful prognostic tests is the lack of improvement in assisted conception success rates despite thirty years of worldwide use. International collaborations should be initiated to develop agreed protocols and establish clinical thresholds.


Assuntos
Adutos de DNA/análise , Dano ao DNA , Infertilidade Masculina/diagnóstico , Técnicas de Diagnóstico Molecular , Espermatozoides/química , Aborto Espontâneo/genética , Blastocisto/metabolismo , Aberrações Cromossômicas , Ensaio Cometa , Anormalidades Congênitas/genética , Desenvolvimento Embrionário , Feminino , Fertilização in vitro , Humanos , Marcação In Situ das Extremidades Cortadas , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Infertilidade Masculina/terapia , Masculino , Técnicas de Diagnóstico Molecular/normas , Estresse Oxidativo , Valor Preditivo dos Testes , Gravidez , Taxa de Gravidez , Injeções de Esperma Intracitoplásmicas/efeitos adversos , Espermatozoides/patologia , Resultado do Tratamento
6.
Mutagenesis ; 23(3): 163-70, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18325925

RESUMO

Infertility affects one in six couples in Europe during their reproductive years with dysfunctional sperm being one of the most common causes. Conventional semen analysis has proven variable and lacking in prognostic value so, over the past decade, more useful molecular fertility biomarkers have been explored. Among the tests showing most promise are those measuring sperm DNA quality. Sperm DNA damage has been closely associated with numerous indicators of reproductive health, including, fertilization, embryo quality, implantation, spontaneous abortion and childhood diseases. It therefore has great potential as a prognostic test for assisted reproductive treatment (ART), when couples are presenting with male infertility. Unlike somatic cells, sperm have a unique tightly compacted chromatin structure. Our group has modified the alkaline comet assay for use with sperm. Sperm DNA also differs from somatic cells in its high susceptibility to oxidative damage; this is largely due to the presence of abundant polyunsaturated fatty acids acting as substrates for reactive oxygen species (ROS) and its lack of repair mechanisms. Consequently, the effects of ROS and antioxidant protection on sperm DNA fragmentation have been widely investigated. In this review, the relationship between actual sperm DNA damage as determined by the alkaline comet assay and potential DNA damage as measured by DNA adduct testing will also be examined and the potential of routine clinical practices such as cryopreservation and prolonged incubation to induce further DNA damage was investigated. Finally, the usefulness of sperm DNA tests as prognostic markers and in particular, the opportunities and challenges provided by DNA testing in male fertility determination will be discussed.


Assuntos
Dano ao DNA , DNA/análise , Infertilidade Masculina/diagnóstico , Espermatozoides/química , Ensaio Cometa/métodos , Ensaio Cometa/normas , Ensaio Cometa/estatística & dados numéricos , Humanos , Infertilidade Masculina/etiologia , Infertilidade Masculina/terapia , Masculino , Estresse Oxidativo , Prognóstico , Técnicas de Reprodução Assistida , Resultado do Tratamento
7.
Hum Reprod ; 22(8): 2169-77, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17588956

RESUMO

BACKGROUND: Diabetics have a significantly higher percentage of sperm with nuclear DNA (nDNA) fragmentation and increased levels of advanced glycation end products (AGEs), in their testis, epididymis and sperm. As the receptor for AGEs (RAGE) is important to oxidative stress and cell dysfunction, we hypothesise, that it may be involved in sperm nDNA damage. METHODS: Immunohistochemistry was performed to determine the presence of RAGE in the human testis and epididymis. A comparison of the receptor's incidence and localization on sperm from 10 diabetic and 11 non-diabetic men was conducted by blind semi-quantitative assessment of the immunostaining. Enzyme-linked immunosorbent assay analysis ascertained RAGE levels in seminal plasma and sperm from 21 diabetic and 31 non-diabetic subjects. Dual labelling immunolocalization was employed to evaluate RAGE's precise location on the sperm head. RESULTS: RAGE was found throughout the testis, caput epididymis, particularly the principle cells apical region, and on sperm acrosomes. The number of sperm displaying RAGE and the overall protein amount found in sperm and seminal plasma were significantly higher in samples from diabetic men (P < 0.01, P < 0.0001 and P < 0.0001, respectively). CONCLUSIONS: The presence of RAGE implies that it may play a central role in sperm nDNA damage particularly in diabetic men where the levels are elevated.


Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Epididimo/química , Receptores Imunológicos/análise , Sêmen/química , Testículo/química , Adolescente , Adulto , Ensaio de Imunoadsorção Enzimática , Produtos Finais de Glicação Avançada , Humanos , Masculino , Pessoa de Meia-Idade , Receptor para Produtos Finais de Glicação Avançada
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