Olfactory marker protein regulates prolactin secretion and production by modulating Ca2+ and TRH signaling in lactotrophs

Olfactory marker protein (OMP) is a marker of olfactory receptor-mediated chemoreception, even outside the olfactory system. Here, we report that OMP expression in the pituitary gland plays a role in basal and thyrotropin-releasing hormone (TRH)-induced prolactin (PRL) production and secretion. We found that OMP was expressed in human and rodent pituitary glands, especially in PRL-secreting lactotrophs. OMP knockdown in GH4 rat pituitary cells increased PRL production and secretion via extracellular signal-regulated kinase (ERK)1/2 signaling. Real-time PCR analysis and the Ca2+ influx assay revealed that OMP was critical for TRH-induced PRL secretion. OMP-knockout mice showed lower fertility than control mice, which was associated with increased basal PRL production via activation of ERK1/2 signaling and reduced TRH-induced PRL secretion. However, both in vitro and in vivo results indicated that OMP was only required for hormone production and secretion because ERK1/2 activation failed to stimulate cell proliferation. Additionally, patients with prolactinoma lacked OMP expression in tumor tissues with hyperactivated ERK1/2 signaling. These findings indicate that OMP plays a role in PRL production and secretion in lactotrophs through the modulation of Ca2+ and TRH signaling. © 2018 The Author(s).1

Genetic polymorphism of merozoite surface protein-1 and merozoite surface protein-2 in Plasmodium falciparum field isolates from Myanmar

<p>Abstract</p> <p>Background</p> <p>Merozoite surface protein-1 (MSP-1) and MSP-2 of <it>Plasmodium falciparum </it>are potential vaccine candidate antigens for malaria vaccine development. However, extensive genetic polymorphism of the antigens in field isolates of <it>P. falciparum </it>represents a major obstacle for the development of an effective vaccine. In this study, genetic polymorphism of MSP-1 and MSP-2 among <it>P. falciparum </it>field isolates from Myanmar was analysed.</p> <p>Methods</p> <p>A total of 63 <it>P. falciparum </it>infected blood samples, which were collected from patients attending a regional hospital in Mandalay Division, Myanmar, were used in this study. The regions flanking the highly polymorphic characters, block 2 for MSP-1 and block 3 for MSP-2, were genotyped by allele-specific nested-PCR to analyse the population diversity of the parasite. Sequence analysis of the polymorphic regions of MSP-1 and MSP-2 was also conducted to identify allelic diversity in the parasite population.</p> <p>Results</p> <p>Diverse allelic polymorphism of MSP-1 and MSP-2 was identified in <it>P. falciparum </it>isolates from Myanmar and most of the infections were determined to be mixed infections. Sequence analysis of MSP-1 block 2 revealed that 14 different alleles for MSP-1 (5 for K1 type and 9 for MAD20 type) were identified. For MSP-2 block 3, a total of 22 alleles (7 for FC27 type and 15 for 3D7 type) were identified.</p> <p>Conclusion</p> <p>Extensive genetic polymorphism with diverse allele types was identified in MSP-1 and MSP-2 in <it>P. falciparum </it>field isolates from Myanmar. A high level of mixed infections was also observed, as was a high degree of multiplicity of infection.</p

Leadership Succession Planning: An Examination of Sole Proprietor Estate Surveying and Valuation Firms in Lagos Metropolis, Nigeria

This paper reports the results from a survey of 38 small sole- proprietor estate surveying and valuation firms in Lagos, Nigeria. A 45% questionnaire retrieval rate was achieved while CEOs/owners of estate surveying and valuation firms were interviewed. Descriptive statistics were used to analyze the respondents‟ general characteristics as well as their attitude toward business succession planning. The study found that sole-proprietor firm owners desired that their firms outlive them through transferring of the firms‟ businesses to their next generation. However, majority of these sole proprietors‟ next generation were not keen on pursuing real estate business related courses in their undergraduate days in view of their exposure to modern technology and the influence of peers. Also, the study found that the owners of these firms have not, as a matter of policy, planned for their succession because of the cultural and attitudinal beliefs and values, which forbid thoughts about death or incapacitation about a living soul. As a result, the study indicated that only 5% of sole proprietor estate surveying and valuation firms in this category have continued to the second generation in the study area. This outcome has serious implications for small professional service businesses‟ economic and job creation potential for Nigeria

In Vivo Biocompatibility Study of Electrospun Chitosan Microfiber for Tissue Engineering

In this work, we examined the biocompatibility of electrospun chitosan microfibers as a scaffold. The chitosan microfibers showed a three-dimensional pore structure by SEM. The chitosan microfibers supported attachment and viability of rat muscle-derived stem cells (rMDSCs). Subcutaneous implantation of the chitosan microfibers demonstrated that implantation of rMDSCs containing chitosan microfibers induced lower host tissue responses with decreased macrophage accumulation than did the chitosan microfibers alone, probably due to the immunosuppression of the transplanted rMDSCs. Our results collectively show that chitosan microfibers could serve as a biocompatible in vivo scaffold for rMDSCs in rats