Finally, the isolation and cloning of black sea bream SL receptor using PCR cloning and protein pull down assay were also attempted. Based on the PCR cloning results, the phylogenetic analysis of nonsalmonids fish GHR1 and SLR protein sequence, the GHR1 data of tissue distribution and effects of environmental salinity and fasting in tilapia, along with the results of far western blot, black sea bream GHR1 is probably a receptor for SL, however there is also a SL specific receptor in black sea bream. / In hormone treated primary cell culture of nonspawning black sea bream pituitary, 10-8 M E2 significantly increases SL mRNA level but 10-10 M, 10-9 M, 10-8 M of E2 inhibit GH mRNA level in female black seabream; 10-8 M E2 also inhibits SL and GH mRNA expression in bisexual black sea bream; 10-8 M MT inhibits SL mRNA expression in male black sea bream but any concentration of MT detected shows no significant effect on GH mRNA level. / Key words. somatolactin (SL), monthly changes, SL promoter, pit-1 and SL receptor / Somatolactin, SL, is a novel member of GH family of pituitary hormone only found in fish. It is considered to be a member of the GH gene family after gene duplication. Two types of SL, SL alpha and SL beta were identified, and SL 13 seems only in fresh water fish, such as goldfish, catfish, rainbow trout, eel and zebrafish. Black sea bream is a marine fish, and there is only SL alpha found from sequencing of over 100 SL cDNA clones. / The cDNAs encoding for transcription factor pit-1 variants were cloned and the transactivation of these Pit-1 isoforms on SL gene promoter were studied. Three variants of Pit-1 are first identified in fish. Pit-1b and Pit-1c can enhance SL promoter activity in Hepa-T1 cells respectively to about 2 fold and 12 fold, but pit-1a failed to activate the SL gene it in the same cells. All the three pit-1s of black sea bream couldn't reverse the inhibition of SL promoter in GH3 cells. The data suggest that N terminal 60 amino acid residues are critical in transactiation on SL promoter and SL promoter activity is possibly limited to fish SL secreting cells. / The SL gene promoter was obtained for gene regulation studies aiming to search for possible regulatory elements controlling the transcription of SL gene in black seabream. SL gene promoter is active in HepaT1 cells, but is inhibited in GH3 cells. Seven putative pit-1 response elements were confirmed with EMSA and super shift assay. / To study the physiological function of SL in black seabream, we initiated a study of monthly expressions of SL mRNA and gonadal somatic index (GSI) to determine whether SL is related to reproduction in black seabream, with GH mRNA levels were also detected for comparison. The results imply that function of SL is possibly related to early development of testis, while GH probably plays some roles in testis and ovary maturation. / by Tian, Jing. / "October 2007." / Source: Dissertation Abstracts International, Volume: 69-08, Section: B, page: 4574. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 156-170). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Wang Yajun. / "April 2003." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (p. 212-248). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

No description available.

No description available.

No description available.

Includes bibliographical references

Passive and active heat loading causes cardiovascular strain, which can have diverse and substantial effects. Thus, cardiovascular function is integral to work and heat stress tolerance, but recent hyperthermia and exercise literature has not emphasised this relationship, instead focusing on the roles of upper �critical� core temperature or rate of heat storage as primary mechanisms of fatigue. Therefore, the aim of this thesis was to examine some potential causes and effects of cardiovascular strain under heat stress, including potential strategies for attenuating that strain. Body precooling before exercise increases heat storage capacity; the primary mechanism by which attenuations in thermal and cardiovascular strain, and improved work capacity is thought to occur. However, no precooling study has utilised realistic airflow in the laboratory, possibly inflating its purported benefits. Therefore, Study One examined the cardiovascular, thermal, psychophysical and ergogenic effects of precooling with and without airflow in the heat (30�C, 50% rh). Ten males completed four trials in balanced order, comprising 60- min immersion in thermoneutral (35�C) or cool (24�C) water before cycling at 95% ventilatory threshold with airflow (~4.8 m�s⁻�) or no airflow, until exhaustion. Heart rate and mean core, body, and skin temperatures were attenuated for 15 min into cycling after precooling. Endurance time was extended by 30 � 23 min with airflow, and 16 � 15 min with precooling relative to control (28 � 12 min) but not further extended with strategies combined (29 � 21 min). Precooling removed 784 � 223 kJ�m⁻� (calorimetrically); less than the effect of airflow alone (1323 � 1128 kJ�m⁻�). Competition for blood between tissues is pronounced during exercise in the heat: skin and gut have marked increases and decreases, respectively. Gut ischemia affects epithelial tight junction integrity, allowing lippopolysaccharide ingress and immune responses. Bovine colostrum may attenuate gut permeability. Study Two (double-blind, placebo controlled) investigated the effects of aerobic fitness (7 highly fit, 8 moderately fit) and bovine colostrum on physiological and perceived strain, and performance during mixed-mode exercise; cycle 15 min at 50% maximal heart rate range (HRR), run 30 min at 80% HRR then 30 min self-selected paced before another 15 min cycle at the same work-rate. Airflow was graded to running speed. During the last cycle, blood pressure, stroke volume and total peripheral resistance were lower, heart rate and skin blood flow increased, and skin temperature was unchanged compared to the first cycle. Indices of fever response (IL-1β, TNF-α) were not evident during exercise, nor were those of blood-brain barrier permeability (S100β) or cognitive impairment (Stroop test). Neither bovine colostrum, nor higher fitness modified these measures. Moving to upright posture is orthostatically stressful and can initially decrease cerebral perfusion. Compression garments are used to assist venous return; while their effectiveness is unknown, they could reduce heat or orthostatic-induced hypoperfusion. Study Three investigated the cardiovascular and cerebrovascular responses to orthostatic stress with and without passive heating (+0.5�C). Fifteen participants completed two trials (compression v placebo garments) in balanced order. Cerebral autoregulation was assessed via 3-min stand, and via thigh cuff inflation. All participants experienced initial orthostatic hypotension upon standing in one or more trials, with 4/15 individuals experiencing presyncopal symptoms, aborting the standing protocol. In those who "fainted", reductions in blood pressure and partial pressure of end-tidal CO₂ reduced middle cerebral artery velocity. Neither training status nor compression trousers modified the responses. Collectively, cardiovascular strain to heat stress is attenuated when realistic airflow is provided. Increased cardiovascular strain does not inevitably result in clinical outcomes to heat stress. Higher fitness does not necessarily attenuate cardiovascular responses or higher tolerance to heat stress.

1v. (various paging) : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (D.Sc.)--University of Adelaide, Dept. of Botany, 1978

Bibliography: leaves 151-187. / xvii, 187 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Agriculture and Natural Resource Sciences, 1993

Copies of author's previously published articles inserted. / Bibliography: leaves 184-197. / xxvi, 197 leaves, [5] leaves of plates : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Soil Science, 1995