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Henry M. "EXPRESSION OF ESTROGEN RECEPTORS ALPHA and beta in boar testis." 15th international congress on animal reproduction (ICAR), Prto Seguro, Brazil; 2004.
Henry M. "One-Health approach for animal disaster management." KVA national conference, Kisumu; 2017.
Henry M. "estrogenic regulation of testicular function." Faculty symposium, giessen, germany; 2004.
HENRY DRM'IKIUGUMUTEMBEI. "MP Kowalewski, HM Mutembei, B Hoffmann 2006: Expression of Prostaglandin sythetase in the corpus luteum of the dog. Reprod Dom Animal 41 (Suppli.1): 21.". In: Animal Reproduction Science 109 (2008) 319. Elsevier; 2006. Abstract
PGFR plays a critical role in determining luteal sensitivity to the luteolytic actions of PGF2a. In the dog the luteal life span can be terminated by exogenous application of PGF2a or its analogues. However, relatively high dosages or repeated treatments are necessary and strong side effects may be observed. In the dog, in contrast to ruminants and other species, luteolysis is not affected by hysterectomy. These observations led to the conclusion that rather paracrine/ autocrine mechanisms than endocrine mechanisms of PGF2a are responsible for luteal regression in the dog. The present experiments were designed to test for the capacity of canine CL to produce and respond to PGF2a. PGFS and PGFR from canine CL from days 5,15, 25, 35, 45, 65 after ovulation were isolated and cloned. A full length PGFS cDNA isolate contains an open reading frame (ORF) of 975 bases coding for a protein of 325 amino acids. The ORF of PGFR consists of 1101 nucleotides encoding a 367 amino acid protein. Both genes show a high homology (82-94%) compared to other species. Relatively weak PGFR mRNA expression was detected on day 5. It had increased by day 25 and remained constant thereafter. In situ hybridization analysis localized the PGFR to the cytoplasm of the luteal cells only, suggesting that those cells are the only targets of PGF2a in this species. Only negative results were obtained when testing for the expression of PGFS by RT-PCR. These data demonstrate that canine CL does not have the capacity to produce PGF2a by PGFS and suggest that luteal regression in non-pregnant bitches is not modulated by PGF2a. However, the PGFR seems to be constitutionally expressed, explaining the receptivity of canine Cl to exogenous PGF2a.
Henry M. "Environmental Governance and its role in Kenya." International Scientific Conference for Asia and Pacific, Yokohama, Japan.; 2018.
Henry M. "Migration, Mobility, Conflict and Climate Change Nexus." VII Conference of Climate Change Action, Safari Park, Nairobi; 2018.
HENRY DRM'IKIUGUMUTEMBEI. "HM Mutembei, ER Mutiga, VT Tsuma 2000: A Retrospective study on Reproductive Parameters of dogs. J South African Vet Ass 71(2): 115-117.". In: Animal Reproduction Science 109 (2008) 319. Elsevier; 2000.
Henry M. "Endocrine regulation of testis." 5th International Congress on Farm animal endocrinology (ICAE), Budapest, Hungary; 2004.
Henry M. "Strategic water towers management." Kenya Institute of Enviroment, Nairobi; 2016.
Henry M. "Connection between Environment and Peace." National Symposium of Peace and Environment, Nairobi.; 2018.
HENRY DRM'IKIUGUMUTEMBEI. "HM Mutembei, S Pesch, G Schuler, B Hoffmann B (2004). Expression of estrogen receptor beta in the boar testis. Vet. Med. Austria/ Wien. Tier.". In: Animal Reproduction Science 109 (2008) 319. Elsevier; 2004.
Henry M. "Endocrine regulation of implantation and placentation in domestic animals." Faculty symposium, giessen, germany; 2004.
HENRY DRM'IKIUGUMUTEMBEI. "HM Mutembei, MP Kowalewski, B Hoffmann 2005: Sus scrofa steroid sulfatase mRNA partial CDs. A Gene Bank Submission, Accession number DQ139314.". In: Animal Reproduction Science 109 (2008) 319. Elsevier; 2005.
Henry M. "Disaster management activities within Livestock sector." KVA national conference, Safari Park; 2015.
Henry M. "Role of estrogen in boar testis." 37th yearly congress on physiology and pathology of reproduction, Munich, Germany; 2004.
Henry M. "Advances in Embryo Transfer Techniques." KVA Kisumu Branch Conference, Kisumu; 2017.
HENRY DRM'IKIUGUMUTEMBEI. "HM Mutembei, S Pesch, M Kowalewski, G Schuler, B Ugele,W Song and B Hoffmann 2006: Expression of Estrogen sulfotransferase in the testis of Immature and Mature boars.Reprod Dom Animal 41 (Suppl.1): 24.". In: Animal Reproduction Science 109 (2008) 319. Elsevier; 2006. Abstract
estrone sulfate (E1S) by far exceeding those of free estrone (E1). Expression of estrogen receptors has been observed in Leydig-, Sertoli- and germ cells. This suggests a paracrine and/or autocrine activity of the Leydig cell derived estrogens. In vitro studies with boar testicular tissue have demonstrated activity of both StS and EST. The bioavailability of free estrone might result from the interplay of both enzymes. We investigated for the localisation of EST enzyme in the testes of immature and mature boars by immunohistochemistry using samples from animals aged 50, 100, 150, 200 and 250 days. Rabbit polyclonal antibodies against human EST alongside negative controls with the rabbit serum were used. In all age groups both the EST was localised, with their signals restricted to the cytoplasm of the Leydig cells. The intensity of EST decreased as the boars matured. RT-PCR confirmed testicular expression of EST, in situ hybridisation confirmed localisation of EST in the Leydig cells. For a functional interpretation further studies are necessary. However, in respect to the lower activity of EST determined in the testis compared to the epididymis and the local circulatory system, rather the epididymis than the testis seems to be the origin of the high E1Sconcentrations determined in the testicular vein plasma.
Henry M. "Follicular dynamics of Boran cow." KVA National Conference, Mombasa; 2014.
Henry M. "REproductive Parameters of German Shepherd Bitches in Kenya." 1st Biennial conference, Nairobi; 1998.
Henry M, Victor T, David K. "Factors Affecting Adoption Of Embryo Transfer Technology In Dairy Cattle In Kenya." Advances in Social Sciences Research Journal. 2019;5(8):456-463.mutembei-kios_2018.pdf
HM M, Kipyegon AN TVT. "Effects of Exposure to Effluent Contaminated River Water on Boar Reproduction." International Journal of Veterinary Science. 2017;6(1):49-52.mutembei_and_kipyegon_2017.pdf
HM M. "staging of Spermatogenesis in the boar." Faculty symposium, giessen, germany; 2005.
HM M. WSPA Global REview.; 2011.
HM M. "Expression of estrogen sulfatransferase in boar testis." 39th yealy congress on physiology and pathology of reprouction, Hannover, Germany; 2006.
HM M. "One-health approach to control incidence of of rabies in Nairobi ." Journal of Medical and Biological Science Research. 2015;1(6):84-87.
HM M. "Rabies control strategies within slum areas." One-health coneference, Adfis Ababa; 2013.
HM M. "Academic Processes of postgraduate studies; from admission to graduation." Kenya Climate Smart Agriculture postgraduate induction workshop, Nakuru; 2019.
HM M, OL O, LC A. Guide to Clinical and Practical Laboratory Procedures in Theriogenology. Ibadan: Scholarship Books; 2019.
HM M. EXPRESSION OF ESTROGEN RECEPTORS ALPHA. Giessen: Annual Research Dissemination for VFFV; 2004.
HM M. "Role of estrogen in autocline and endocrine regulation of spermatogenesis." Faculty symposium, giessen, germany; 2005.
HM M. "Climate Change as Driver of Migration, morbidity and Conflicts in Africa." Red Cross Headquarters, Nairobi; 2019.
HM M. "Expression of P450 aromatase in boar testis." 38th yearly congress on physiology and pathology of reproduction, Zurich, Switzerland; 2005.
HM M. "Veterinary Response." in standard operating procedures for staff working in disasters, London; 2013.
HM M. "WSPA Post Intervention Report." Word Animal Protection Online news. (2012).
HM M. "Use of assisted reproductive technologies in cattle." Biennial scientific conference, Nairobi; 2010.
HM M. "Effective monitoring and Evaluation of progress in postgraduate training." Kenya Climate Smart Agriculture postgraduate induction workshop, Nakuru; 2019.
HM M. "Role of estrogens in the testis as deduced by espression of receptors." Faculty symposium, giessen, germany; 2004.
HM M. "Role of estrogen in regulation of spermatogenesis." Faculty symposium, giessen, germany; 2005.
HM M. "Expression of estrogen receptors in boar testis." 40th yearly congress of physiology and pathology of reproduction, Berlin, Germany; 2007.
HM M. "Tips on timely completion of postgraduate studies." Kenya Climate Smart Agriculture postgraduate induction workshop, Nakuru; 2019.
HM M. REproductive Parameters of German Shepherd Bitches in Kenya. Nairobi: University of Nairobi Press; 1998.
Hoffmann B, Rostalski A, Mutembei HM, Goericke-Pesch S. "Testicular steroid hormone secretion in the boar and expression of testicular and epididymal steroid sulphatase and estrogen sulphotransferase activity.". 2010. Abstract

BACKGROUND: Spermatogenesis and epididymal function depend on testicular steroids with estrogens being important regulatory factors. However, testicular estrogen secretion shows distinct species specificities, with the boar being characterized by the production of high amounts of estrone [E1] and estronesulphate [E1S]. As the boar testis also expresses estrogen sulphatase [StS] and sulphotransferase [EST] the present paper is based on the hypothesis that local availability of biologically active estrogens results from an interplay between estrogen synthesis and local activities of StS and EST. METHODS: Blood was collected during castration of 37 boars, aged between 98 (peripubertal) to 2 793 (old sexually mature) days, from the testicular vein and artery and peripheral circulation; E1, E1S, testosterone [T] and progesterone [P] were determined by established RIA-procedures. Similarly seminal plasma from 21 sexually mature boars was assessed. StS- and EST-activity were determined in testicular- and epididymal homogenates of 3 sexually mature boars (200 d) using (3)H-E1S resp. (3)H-E1 as substrate. Immunohistochemistry [IHC] was applied to locate EST- expressing cells in testes in relation to age and in the epididymis of 3 mature boars. RESULTS: Hormone data showed a high variability. A significant age dependent increase was only observed for E1 and E1S in the peripheral circulation with absolute values being highest for E1S (5-60 nmol/l), followed by T (2.6-14 nmol/l), P (0.5-1.48 nmol/l) and E1 (0.24-0.84 nmol/l). Testicular vein concentrations always exceeded those in the testicular artery with the differences being significant for E1 and P, group 1. Concentrations in the testicular artery and peripheral vein plasma were not different but higher (p<0.0001) than those in seminal plasma with the exception of E1. StS activity was higher (p<0.001) in the testis than the epididymis. EST activity was high in epididymal homogenates and at the level of detection in testis homogenates. IHC located EST in virtually all epididymal epithelial cells. In the testis the number of positive staining Leydig cells decreased (p<0.05) from 72% in the premature to 57% in the mature boars. CONCLUSION: The provision of biologically active estrogens to the testicular and epididymal compartment is controlled by a complex regulatory system, with the sulphatase pathway being an important component. P is a secretory product of the testis, E1 and E1S are not actively enriched in seminal plasma.

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