Genetic parameters of birth weight trait in dromedary camels (Camelus dromedarius).

Birth weight data of dromedary calves from the database of one of the world's largest dairy herds (Dubai, UAE) were analyzed for the period from 2007 to 2018. The assessment included the data of 4124 camel calves that were classified into six ecotypes (Emirate, Emirate crossed, Black, Pakistanian, Saudi-Sudanian, and Saudi crossed). The aim of the study was to describe the heritability of birth weight of calves and the breeding value of sires. Genetic parameters of birth weight were estimated by ANOVA model and two BLUP animal models as well. The mean value of the camel calves' birth weight was 34.75 ± 5.67 kg. The direct heritability of birth weight (h2d = 0.09 ± 0.04-0.11 ± 0.03) was rather low, so was the maternal heritability (h2m = 0.23 ± 0.10-0.50 ± 0.06). The maternal effect from environmental origin (c2 = 0.23 ± 0.08) far exceeded the results previously calculated in cattle. There was no difference in reliability between BLUP1 and BLUP2 models, and both of them were more accurate than the ANOVA model. Based on the results of this study, we conclude that the birth weight of dromedary calves was more influenced by the dam's intrauterine rearing capacity and by the environment, management, and feeding of the pregnant female camels than the hereditary growth potential. Considerable differences were found among male dromedaries in their breeding values for the birth weight trait.

Driving safety improves after individualized training: An RCT involving older drivers in an urban area.

Objective: This study aimed to reproduce the results of a previous investigation on the safety benefits of individualized training for older drivers. We modified our method to address validity and generalizability issues. Methods: Older drivers were randomly assigned to one of the 3 arms: (1) education alone, (2) education + on road training, and (3) education + on road + simulator training. Older drivers were recruited from a larger urban community. At the pre- and posttests (separated by 4 to 8 weeks) participants followed driving directions using a Global Positioning System (GPS) navigation system. Results: Our findings support the positive influence of individualized on-road training for urban-dwelling older drivers. Overall, driving safety improved among drivers who received on-road training over those who were only exposed to an education session, F(1, 40) = 11.66, P = .001 (26% reduction in total unsafe driving actions [UDAs]). Statistically significant improvements were observed on observation UDAs (e.g., scanning at intersections, etc.), compliance UDAs (e.g., incomplete stop), and procedural UDAs (e.g., position in lane). Conclusion: This study adds to the growing evidence base in support of individualized older driver training to optimize older drivers' safety and promote continued safe driving.

Effect of DGAT1 and TG gene polymorphisms on intramuscular fat and on milk production traits in different cattle breeds in Hungary.

The objective of this study was to estimate the effect of the thyroglobulin (TG) locus on beef quality traits in some beef cattle breeds and to investigate the effect of the DGAT1 locus on milk production traits in the Hungarian Holstein Friesian population. TG and DGAT1 genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. At the TG locus TT bulls showed the highest fat percentage values in the longissimus dorsi muscle (m. longissimus dorsi); the difference between CC and TT genotypes was significant. DGAT1 GC/GC cows had the highest milk, fat and protein yield values. Due to the relatively small number of GC/GC cows the difference proved to be significant only between AA/AA and AA/GC genotypes.

Platelet vinculin: a substrate of activated factor XIII.

In addition to plasma, Factor XIII of blood coagulation (FXIII) is also present in the cytosol of platelets, monocytes and macrophages. However, its intracellular function has not yet been revealed. Activated Factor XIII (FXIIIa) is a transglutaminase (protein-glutamine: amine gamma-glutamyltransferase, EC 2.3.2.13) of highly restricted substrate specificity with only a few known protein substrates. In this report, we showed that FXIIIa can link dansylcadaverine, radiolabelled histamine and putrescine to vinculin. Quantitative determinations revealed that in the vinculin molecule a single glutamine residue can serve as acyl donor for the incorporation of small-molecular-weight amines. Vinculin could not be crosslinked to another vinculin molecule. It could be covalently bound, however, to fibrinogen, which indicates that the acyl donor glutamine residue can be engaged in an epsilon-(gamma-glutamyl)lysyl crosslink formation. Since it has been shown that platelet actin and myosin, two main components of cytoskeleton, are also substrates for FXIIIa, and that vinculin is associated to the cytoskeleton during platelet activation, the involvement of FXIII in the stabilization of cytoskeleton at certain phases of cellular function is a likely possibility.

The P-selectin, tissue factor, coagulation triad.

The primary importance of tissue factor (TF) in blood coagulation and thrombus propagation has been recognized for many years. Nevertheless, our view about the origin of TF activity, necessary for normal hemostasis and found in pathologic conditions, needs to be revised in the light of recent observations. Pioneering work by Yale Nemerson's group showed that circulating TF on microparticles (MPs), could promote thrombus growth. The origin and characteristics of this 'blood-borne' TF are targets of intense research as well as intense debate. Surprising observations now implicate the adhesion receptor P-selectin (P-sel), known for its role in inflammation, in these MPs' generation. P-sel, translocated from granules to the cell surfaces of activated platelets and endothelial cells, was recently found to play multiple roles in hemostasis. Expressed on endothelium, it can mediate platelet rolling. Signaling by P-sel through its receptor on leukocytes, P-selectin glycoprotein ligand 1 (PSGL-1), induces the generation of TF-positive, highly procoagulant MPs. In addition, P-sel on activated platelets helps to recruit these MPs specifically to thrombi. In this review, we discuss the roles of P-sel and TF-positive MPs and highlight strategies to modulate hemostasis by modulating the P-sel, TF, coagulation triad.

Additional GPI-anchored glycoproteins on human platelets that are absent or deficient in paroxysmal nocturnal haemoglobinuria.

In order to detect novel glycophosphatidylinositol (GPI)-anchored platelet proteins, human platelets were incubated with PI-specific phospholipase C (PI-PLC) and the supernatant was analysed by PAGE and silver-staining for additional protein bands. PI-PLC treatment resulted in the appearance of at least two additional novel GPI-linked glycoproteins (GP), GP500 and GP175, in the supernatant. Their presence on the platelet plasma membrane surface was demonstrated by periodate/[3H]borohydride surface-labelling. Activation of platelets did not enhance the amount of GP500 and GP175 that could be cleaved by PI-PLC. In Triton X-114 phase partitioning of platelet membranes the membrane form of GP175, mfGP175, was in the Triton phase while mfGP500 was found in the water phase. Neither GP500 nor GP175 were present in the supernatant of surface-labelled platelets treated with PI-PLC from 4 patients, diagnosed as having paroxysmal nocturnal haemoglobinuria (PNH), but the supernatant from platelets from healthy volunteers treated the same way contained both.

Platelet factor XIII becomes active without the release of activation peptide during platelet activation.

The potentially active A subunit of factor XIII of blood coagulation has also been detected in platelets and monocytes/macrophages through the exact function of this cellular protransglutaminase has not yet been elucidated. In physiological conditions the first step in the activation of plasma factor XIII is the removal of an activation peptide from the N-terminal end of subunit A by thrombin. The A subunit then, in the presence of Ca2+, dissociates from the inhibitory B subunit and assumes an active conformation. Cellular factor XIII, which lacks B subunit, can be proteolytically activated in vitro by thrombin and the intracellular Ca2+ sensitive protease, calpain, in the same way as plasma factor XIII subunit A, and calpain has been suggested as the intracellular protease involved in the activation of cellular factor XIII in platelets. In the present experiments it was shown by SDS PAGE that during long-term stimulation of platelets with thrombin nondisulfide-crosslinked high M(r) protein polymers not penetrating the concentrating gel were formed. The lack of these polymers in thrombin-stimulated factor XIII deficient platelets clearly indicated that their formation in normal platelets was due to factor XIII that became active during platelet activation. However, no release of the activation peptide could be detected by Western blotting during this process. Similarly, no proteolytic cleavage of factor XIII was detectable when platelets were stimulated by Ca2+ ionophore through this stimulus activated calpain as it was clearly demonstrated by the breakdown of major intracellular calpain substrates.(ABSTRACT TRUNCATED AT 250 WORDS)

Transformation of cellular factor XIII into an active zymogen transglutaminase in thrombin-stimulated platelets.

The cellular form of blood coagulation factor XIII (FXIII) is present in platelets, monocytes and macrophages. During long-term stimulation of platelets by thrombin cellular FXIII becomes activated and cross-links proteins, however, the mechanism of its activation has not been elucidated. It was shown that, contrary to plasma FXIII, the intracellular activation of platelet FXIII does not involve proteolysis. FXIII remained intact in thrombin-activated platelets, i.e., the activation peptide was not removed from the molecule. Part of the zymogen FXIII molecules, however, assumed an active configuration as was demonstrated both by the measurement of transglutaminase activity and by active-site-SH titration. These findings clearly indicate that during platelet activation, when intracellular Ca2+ concentration is raised, a slow non-proteolytic transformation of FXIII zymogen into an active transglutaminase occurs.

Platelet glycoprotein Ia* is the processed form of multimerin--isolation and determination of N-terminal sequences of stored and released forms.

Glycoprotein Ia* (GPIa*), a very high molecular mass, platelet alpha-granule protein consisting of 167 kDa subunits disulphide-linked in a multimeric structure, was first described by Bienz and Clemetson in 1989 (J. Biol. Chem. 264, 507-514). In 1991 Hayward et al. (J. Biol. Chem. 266, 7114-7120) independently identified a platelet protein with multimeric structure. Despite strong similarities to GPIa* they concluded that it was a novel multimeric protein and named it first p-155 and later, multimerin. Multimerin has also been found in endothelial cells and has been cloned recently from an endothelial cell cDNA library. This has made it possible for us to clarify the relationship between GPIa* and multimerin. GPIa* was isolated from platelet releasate and the N-terminal sequence of 167 kDa and 155 kDa subunit species were determined. The N-terminal 15 amino acids of GPIa* were identical to the deduced amino acids 184-198 of endothelial multimerin. The N-terminal sequence of the 155 kDa protein was identical to the deduced amino acids 318-326 of multimerin. Thus, platelet GPIa* (167 kDa) is the main processed form of multimerin stored in platelet alpha-granules. The GPIa*/processed multimerin (167 kDa) still contains an RGDS sequence near its N-terminus as well as an EGF domain which may be involved in binding to the platelet surface after release. This sequence and domain are cleaved off in the p-155 form, described earlier as platelet multimerin, which is probably formed after release from alpha-granules.

Factor XIII of blood coagulation in human monocytes.

The presence of Factor XIII subunit a was demonstrated in human monocytes by immunoperoxidase staining using specific antisera against Factor XIII and its subunits. This finding was verified by immunobiochemical techniques, as well. In an immunoblotting system after SDS polyacrylamide gel electrophoresis of denatured monocyte homogenate a protein band comigrating with Factor XIII subunit a showed positive reaction with antibodies against this subunit or whole Factor XIII. In contrast, no subunit b of Factor XIII could be detected by either of these methods in monocytes. Activity measurements were carried out by the dansylcadaverine incorporation assay in the absence and presence of anti-Factor XIII antibody with and without thrombin activation. The expression of transglutaminase activity required thrombin and was completely abolished in presence of anti- Factor XIII antibody, which clearly indicate that practically all the transglutaminase activity measured in monocytes comes from Factor XIII. Factor XIII of monocytes and macrophages might have a role in formation of focal fibrin thrombi as well as in organization of stable, fibrinolysis resistant fibrin clot at the site of inflammation or around tumor cells.

Success in life for older adolescents with cerebral palsy.

In this article, the psychosocial themes emerging from an exploratory qualitative study are reported. Using a constant comparative method, the authors describe how older adolescents with cerebral palsy defined success in life and the factors they viewed as helping or hindering their success. Participants were 10 adolescents with cerebral palsy between 18 and 20 years of age who took part in a semistructured interview exploring their perceptions of success. For these adolescents, success meant being happy in life. Three key psychosocial factors were related to success in life: being believed in, believing in yourself, and being accepted by others (belonging). The findings are useful in guiding the design of services to meet the life needs of individuals with disabilities.

Enabling occupational performance: optimal experiences in therapy.

Occupational therapists believe that engagement in occupation contributes to health through an individually balanced use of time, a positive focus for one's physical and mental energy, and the provision of a sense of purpose. Flow is a construct which describes optimal experiences or enjoyment in everyday activities. A review of the literature suggests that the theory of optimal experience is complementary to occupational therapy beliefs and that an understanding of the flow experience may contribute to our understanding of human occupation. Specifically, flow may be useful in understanding those aspects of the occupation, environment and person that contribute to a "just right" challenge, and to enabling occupational performance through enjoyable, structured and purposeful activity. Occupational therapists are encouraged to explore whether optimal experiences facilitate occupational performance for individuals with a disability. Future research could explore whether the occupational opportunities available to persons with a disability provide the degree of challenge required to elicit the optimal experience. Finally, research could explore whether the client-driven selection of meaningful occupation, and therapist enablement of the "just right" challenge, influences optimal experience, occupational performance, and life satisfaction for those with a disability.

Meaning of occupational engagement in life-threatening illness: a qualitative pilot project.

INTRODUCTION: The onset of a personal crisis combined with the resultant disruption in occupational routines may challenge a person's identity as a capable and healthy individual. However, it remains unclear how individuals regain a sense of health and well-being in the period following a personal crisis. RESEARCH OBJECTIVE: To explore occupational engagement and its meaning to individuals following a life-threatening diagnosis. METHOD: Semi-structured interviews were conducted with three women diagnosed with breast cancer. The data were analyzed using a constant-comparative approach to identify common themes. RESULTS: The primary theme that emerged was "Doing = Living." This theme and the underlying themes illustrated the connection between meaningful occupational engagement and one's self-perception as capable and healthy. These findings suggest that occupational engagement may provide the medium through which 'deconstructive' or 'reconstructive' messages concerning the self are relayed between persons and their environment. IMPLICATIONS: In a period of personal crisis, such as a life-threatening diagnosis, individuals may turn to those occupations that are meaningful to regain a sense of control and normalcy in their lives.

A critical role for N-ethylmaleimide-sensitive fusion protein (NSF) in platelet granule secretion.

The molecular mechanisms that regulate membrane targeting/fusion during platelet granule secretion are not yet understood. N-ethylmaleimide-sensitive fusion protein (NSF), soluble NSF attachment proteins (SNAPs), and SNAREs (SNAP receptors) are elements of a conserved molecular machinery for membrane targeting/fusion that have been detected in platelets. We examined whether NSF, an ATPase that has been shown to play a critical role in membrane targeting/fusion in many cell types, is necessary for platelet granule secretion. Peptides that mimic NSF sequence motifs inhibited both alpha-granule and dense-granule secretion in permeabilized human platelets. This inhibitory effect was sequence-specific, because neither proteinase K-digested peptides nor peptides containing similar amino acids in a scrambled sequence inhibited platelet secretion. The peptides that inhibited platelet granule secretion also inhibited the human recombinant alpha-SNAP-stimulated ATPase activity of recombinant NSF. It was also found that anti-NSF antibodies, which inhibited recombinant alpha-SNAP-stimulated ATPase activity of NSF, inhibited platelet granule secretion in permeabilized cells. The inhibition by anti-NSF antibodies was abolished by the addition of recombinant NSF. These data provide the first functional evidence that NSF plays an important role in platelet granule secretion.