Molecular Genetic Technology in Beef Cattle Breeding

Chung, E. R. 한림대학교 한림과학원 부설 환경ㆍ생명과학연구소 1999 국제학술회의 Vol.1999 No.-

Biology of Aβ Amyloid in Alzheimer's Disease

Grangione, Blas,Ghiso, Jorge,Wisniewski, Thomas 한림대학교 한림과학원 부설 환경ㆍ생명과학연구소 1998 국제학술회의 Vol.1998 No.-

The genetic associations with the pathological features of AD are diverse: A rapidly growing number of mutations in presenilin 1 and 2 on chromosomes 14 and 1, respectively, are found in many early-onset FAD patients (Lendon et at., 1997). In addition, βPP mutations are found in a small percentage of early-onset FAD kindreds. The apoE4 allele on chromosome 19 is associated with the presence of the most common form of AD, sporadic AD (Winsiewski & Frangione, 1992; Namba et al., 1991). However, it is clear that other proteins are also involved in the pathogenesis of AD, since some early-onset FAD kindreds do not have linkage to PS1, PS2, apoE, or βPP, while at least 50% of late-onset AD is unrelated to apoE. Other proteins which have been implicated in the formation of senile plaques, but so far are not known to have any genetic linkage to AD, include proteoglycans (Snow et al., 1987), apoA1(Wisniewski et al., 1995a), α₁-antichymotrypsin(Abraham et al., 1988), HB-GAM(Wisniewski et al., 1996a), complement components (McGeer & Rogers, 1992), acetylcholinesterase (Friede, 1965), and NAC (Ueda et al., 1993). Which of these proteins will be the most important for the etilogy of the most common form of AD, late-onset sporadic AD, remains an open question. Three of the genes which are now known to be linked to AD, including PS1, βPP, and apoE, have been established immunohistochemically and biochemically to be components of senile plaques (see Fig.1). This raises at least two possibilities; either each of these proteins is part of one pathway with Aβ-related amyloid formation as a final causative pathogenic event or amyloid deposition in AD is a reactive process related to dysfunction of a number of different CNS proteins. Whether or not amyloid formation is directly causative in the pathogenesis of AD, current data suggest that new therapeutic approaches which may inhibit the aggregation and/or the conformational change of sAβ to Aβ fibrils (Soto et al., 1996) have the greatest likelihood to make a significant impact on controlling amyloid accumulation in AD.

Introduction to Beef Cattle Breeding in China

Wang, C. D.,Lee, C. 한림대학교 한림과학원 부설 환경ㆍ생명과학연구소 1999 국제학술회의 Vol.1999 No.-

This paper presents a brief introduction about the Chinese beef cattle industry and the breeding of Chinese Simmental cattle. Although significant progress has been made, the Chinese beef cattle industry has a long way to go. Chinese Simmental cattle breeding aims to develop a crossbred between Simmental and Chinese local yellow cattle to thrive in various climates all over the country, and to meet demands of beef industry. The crossbreds are updated by Simmental bulls for 2 to 5 generations to form a foundation population. With various production conditions in different areas of China there are three types of Chinese Simmental cattle, plain-type, pasture-type and upland-type. The opened nucleus breeding system with intensive breeding unit is adopted. The multiple ovulation and embryo transfer (MOET) technology as well as mixed model methodology are initially put into practice. China needs to continously import superior genetic material and to establish a complete MOET breeding scheme. Chines Simmental cattle will possibly be divided into specialized dairy cattle and beef cattle.

Retrograde Tracing in the Vagal Efferents and Its Branches Projecting to the Esophagus and Stomach in the House Musk Shrew, Suncus Murinus

Won, Moo-Ho 한림대학교 한림과학원 부설 환경ㆍ생명과학연구소 1995 국제학술회의 Vol.1995 No.-

It is well noted that the vague nerve has heterogenous components, i.e., preganglionic parasympathetics; visceral afferents that follow its peripheral distribution; motoneurons to the pharynx, larynx and upper esophagus; gustatory fibers from near the epiglottis; and somatic afferents from the external ear. The vagus nerve is involved in many autonomic and various regulatory functions (Stephenson et al., 1988; Berthoud et al., 1991; Chambert et al., 1993). Brainstem neurons associated with autonomic and regulatory functions are difficult to describe because often they do not aggregate in histologically well defined nuclei. The central efferent organization of the vagus nerve and vagal efferent neurons projecting to some viscerae have been documented by techniques based on retrograde tract-tracing methods in many laboratory species. Vagal efferent axons originate in either the dorsal motor nucleus of the vagus nerve (DMX) or in the vincinity of the ambigual nuclus (AN) (Norgren and Smith, 1988; Pagani et al., 1988; Hudson, 1989; Okumura and Namiki, 1990; Altschuler et al., 1991; Jou et al., 1993; Ranson et al., 1993). However, studies of the neurons projecting to the esophagus and stomach with HRP or other neuronal tracers have provided conflicting results with regard to a viscerotopic organization within the DMX and AN (Okumaura and Namiki, 1990; Altschuler et al., 1991; Jou et al., 1993; Ranson et al., 1993). On the basis of their results, it is speculated that a viscerotopic organization might exist in the DMX and AN, and that different cell groups in the DMX and AN have different functions. Some authors, however, claim that vagal targets do not show discrete or topographic representation, at least in the DMX of the some species (Hudson, 1989). It, therefore, remains unknown whether or not the viscerotopic organization exists for the DMX and AN neurons projecting to the target visceral organs. The house musk shrew, belonging to the Insectivora, has been domesticated by Oda and Kondo (1977) for use in various types of experimental manipulation. The present study, therefore, was performed (1) to identify the central organization of the efferent neurons of the cervical vagus nerve, (2) to localize the distribution of the neurons projecting to the esophagus and stomach, and (3) to examine the possibility of a viscerotopic organization of the projecting neurons within the brainstem nuclei in the house musk shrew.

Current Status of Epidemiologica Research on Dementia in Korea

Suh, Guk-Hee 한림대학교 한림과학원 부설 환경ㆍ생명과학연구소 1998 국제학술회의 Vol.1998 No.-

Dementia is one of the most severe mental health problems commonly found in the aged population. With the increase of the proportion of the elderly, the number of dementia patients is rising in most population. During the past decades several studies of the prevalience of dementia have been performed in a variety of populations and using various methods. Reviews of the literature have generally stressed the methodological differences between studies. I present here the findings of prevalence studies of the dementia performed or published after 1985 in Korea and neighbor Asian countries. Jorm et al(1987) insisted that there were national differences in the relative prevalence of Alzheimer's disease and vascular dementia, with vascular dementia being more common in Japanese and Russian studies after analyzing data between 1945 and 1985. The reason why I select the studies after 1985 at reviews of the literature is to trace changes in the regional or racial differences of the prevalence of dementia in far Eastern countries. One of the objective of this paper was to select the existing prevalence studies that were methodologically similar and suitable for comparison, in order to describe geographical differences and to provide an overall estimate of the prevalence of dementia in far-Eastern countries. In Korea, a few epidemiological studies of demential in the elderly have been performed since 1991. But, there was only one Korean study to identify risk factors of dementia(Suc et al, unpublished). I would like to introduce an epidemiological study for demential in the elderly, with presentation of the results from other Korean researchers and show you some international comparison of these results. Here, I report the prevalence of Dementia of the Alzheimer's Type(DAT) and Vascular Dementia(VaD) in Yeonchun country and the effect of risk factors on the prevalence. this study is based on a recently completed probability sample survey of 1,037 community dwelling persons, 65 years and older.

Intrinsic Biological Aging As Underlying Pathogenetic Mechanisms In Dementias Of The Alzheimer's Type

Martin, George M. 한림대학교 한림과학원 부설 환경ㆍ생명과학연구소 1998 국제학술회의 Vol.1998 No.-

Beef cattle breeding in Canada

Song, H. 한림대학교 한림과학원 부설 환경ㆍ생명과학연구소 1999 국제학술회의 Vol.1999 No.-

To produce better beef more efficiently, genetics of beef cattle must be improved, which requires a nationwide, long-term genetic improvement program for beef cattle. Agriculture Canada started performance test programs (ROP program for beef) in 1956; (a) Station test and (b) the On-farm test. Station test program were effective in playing an important role for the genetic improvement of Canadian beef cattle up to the middle of 1980's. As the national EBVs became available in Canada since 1976 the importance of using station-tested bulls began to erode significantly since late 1980's for reason of its incapability of identifying the best animals on a national base. Routine evaluation of EBVs on 7-traits seemed to provide most of the tools needed for Canadian beef producers to maximize both genetic gain and production efficiency of their own herds. Toward the development of new trends in today's consumers demand for leaner beef with higher eating quality which are uniform and predictable in consistency with a minimum level of variations for given qualities, Canadian beef breeders will have to improve not only those traits of importance of the past but also for carcass traits of importance int he future. The sue of advanced technologies and devices will become necessary, but the on-farm test program will continue to be the bases of Canadian beef improvement program.

Historical look at the genetic improvement in Korean cattle

Kim, J. B.,Lee, C. 한림대학교 한림과학원 부설 환경ㆍ생명과학연구소 1999 국제학술회의 Vol.1999 No.-

Korean cattle industry is important to farming households, national economy, and security of foodstuffs in Korea. Since Korean cattle have had inferior ability to produce meat, Korean cattle industry aimed to improve the meat production ability and to increase number of heads to meet the demand from growing beef cattle market in Korea. This paper reviewed a historical look at the Korean cattle industry and surveyed the efforts devoted to improve genetic abilities of the Korean cattle. Discussed were current situations of the Korean cattle industry, projects related to improvement of Korean cattle, Korean cattle's genetic characteristics of economic traits, and some issues to deal with.

The Characteristics of SAM and Its Related Researches in Korea

Han, Sang-Seop 한림대학교 한림과학원 부설 환경ㆍ생명과학연구소 1995 국제학술회의 Vol.1995 No.-

Molecular Pathogenesis of Spongiform Encephalopathies

Aguzzi, Adriano 한림대학교 한림과학원 부설 환경ㆍ생명과학연구소 1995 국제학술회의 Vol.1995 No.-

Experiments based on the modification of the mammalian germ line genome are changing our understanding of the pathogenesis of various diseases, notably including neurodegenerative conditions. We are using mice bearing specific germ line mutations to study the pathogenesis of transmissible spongiform encephalopathies(TSEs). the latter comprise a group of slow degenerative diseases of the CNS such as Creutzfeldt-Jakob disease(CJD), Gerstamann-Sträussler-Scheinker disease(GSS) and kuru in man, and scrapie or BSE(mad cow disease) in cattle. The unsusal properties of the pathogenic agent, designated as "prion"(Prusiner, 1982) include the extremely long incubation periods, exceeding one year, and resistance to high temperatures, formaldehyde treatment and UV irradiation(Gordon, 1946; Pattison, 1965: Alper et al., 1966; Latarjet et al., 1970). Speculations arose early on that the scrapie agent might be devoid of nucleic acid(Alper et al., 1967; Gibbons and Hunter, 1967; Pattison and Jones, 1967). Considerable evidence has now supports the "protein only" hypothesis(Prusiner and Hsiao, 1994; Weissmann, 1994) which proposes that the prion is devoid of nucleic acid and identical with PrP^Se, a modified form of PrP^c. PrP^c is a normal host protein(Oesch et al., 1985; Chessebro et al., 1985) found predominantly on the outer surface of neurons, but also in many other tissues(Manson et al., 1992; Bendheim et al., 1992). PrP^Se is defined as a protease resistant form of PrP^c which readily forms aggregates after detergent treatment(McKinley et al., 1991). No chemical differences have so far been detected between PrP^Se and PrP^c(Stahl et al., 1993).