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1.
Nature ; 2024 May 29.
Article in English | MEDLINE | ID: mdl-38811737

ABSTRACT

A large qubit capacity and an individual readout capability are two crucial requirements for large-scale quantum computing and simulation1. As one of the leading physical platforms for quantum information processing, the ion trap has achieved a quantum simulation of tens of ions with site-resolved readout in a one-dimensional Paul trap2-4 and of hundreds of ions with global observables in a two-dimensional (2D) Penning trap5,6. However, integrating these two features into a single system is still very challenging. Here we report the stable trapping of 512 ions in a 2D Wigner crystal and the sideband cooling of their transverse motion. We demonstrate the quantum simulation of long-range quantum Ising models with tunable coupling strengths and patterns, with or without frustration, using 300 ions. Enabled by the site resolution in the single-shot measurement, we observe rich spatial correlation patterns in the quasi-adiabatically prepared ground states, which allows us to verify quantum simulation results by comparing the measured two-spin correlations with the calculated collective phonon modes and with classical simulated annealing. We further probe the quench dynamics of the Ising model in a transverse field to demonstrate quantum sampling tasks. Our work paves the way for simulating classically intractable quantum dynamics and for running noisy intermediate-scale quantum algorithms7,8 using 2D ion trap quantum simulators.

2.
Article in Chinese | MEDLINE | ID: mdl-37006146

ABSTRACT

Objective: To investigate the current situation of job involvement of nurses in military hospitals in Henan Province and analyze the influencing factors, so as to provide reference for improving the level of job involvement of military nurses. Methods: In February 2022, the employed nurses of 4 military hospitals in Henan Province were investigated by convenient sampling method. A total of 663 questionnaires were collected, including 632 valid questionnaires, with an effective recovery rate of 95.32%. The self-designed questionnaire was used to investigate the basic information of nurses, the Job Involvement Scale was used to investigate the job involvement of nurses, the Emotional Labor Scale for Nurses was used to investigate nurses' emotions, and the Work-Family Conflict Scale was used to investigate the work-family conflict of nurses. Independent sample t-test and univariate analysis of variance were used to compare the job involvement of military employed nurses with different demographic characteristics, Pearson correlation analysis was used to explore the correlation between emotional labor, work-family conflict and job involvement, and hierarchical regression analysis was used to explore the impact of relevant variables on the job involvement of military employed nurses. Results: The total average score of job involvement of military employed nurses was (3.68±1.13), and the scores of vitality, dedication and focus were (3.64±1.15), (3.74±1.25) and (3.67±1.21) respectively. The total score of emotional labor of nurses was 33-80 (62.95±8.12), with an average score of (3.93±0.51). The total score of work-family conflict was 18-94 (55.16±13.53), with an average score of (3.06±0.75). Professional emotional regulation, patient-centered emotional inhibition and standardized emotional play were positively related to the job involvement (r=0.46, 0.41, 0.22, P<0.01). Time-based conflict, stress-based conflict and behavior-based conflict had negative correlation with the job involvement (r=-0.12, -0.23, -0.20, P<0.01). In hierarchical regression analysis, after controlling demographic variables, emotional labor and work-family conflict accounted for 17.2% and 4.2% of the variation of job involvement. Conclusion: The job involvement of military employed nurses tends to be at a moderate level. Emotional labor and work-family conflict can significantly affect their job involvement.


Subject(s)
Hospitals, Military , Nurses , United States , Humans , Family Conflict , Surveys and Questionnaires , Regression Analysis , Job Satisfaction
3.
Int Nurs Rev ; 66(2): 242-249, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30474113

ABSTRACT

AIM: To investigate the impacts of leader-member exchange and team-member exchange on job satisfaction and turnover intention of nurses. BACKGROUND: Leader-member exchange refers to the quality of relationships between leaders and members of a team and studies on this have generally focused on the aspect of member-leader-member exchanges. In nursing, the latter can refer to a situation where nurses (members) evaluate their relationship with their head nurse (leader). Member-leader-member exchange affects job satisfaction and turnover intention of nurses. However, even though all of these types of exchanges are important, few studies have examined their effects on job satisfaction and the turnover intention of nurses. METHODS: Participants in this descriptive study were 40 head nurses and 284 clinical nurses working at three hospitals in Korea. Data were collected from a questionnaire and analysed using hierarchical multiple regression. RESULTS: Leader-leader-member exchange, member-leader-member exchange, and team-member exchange had a positive effect on job satisfaction. However, only leader-leader-member exchange and member-leader-member exchange affected turnover intention. CONCLUSIONS: The impacts of leader-leader-member exchange, team-member exchange, and member-leader-member exchange on job satisfaction were confirmed. To reduce turnover intention, our study found it is more important to improve leader-member exchange than team-member exchange. IMPLICATIONS FOR NURSING PRACTICE: In health organizations, there is an important need to focus on the communication and exchange relationships between leaders and their staff, well as among the members, to increase job satisfaction. This will assist leaders to play an important role in lowering nurses' turnover intention and create an organizational culture in which nurses can communicate well with them. IMPLICATIONS FOR NURSING POLICY: Policy changes are needed so that the components of job performance evaluation for nurse leaders also include attendance at regular programmes, such as training to improve their leadership and communication skills, and consultations with their staff members.


Subject(s)
Cooperative Behavior , Interprofessional Relations , Job Satisfaction , Leadership , Organizational Culture , Personnel Turnover/statistics & numerical data , Adult , Attitude of Health Personnel , Female , Humans , Male , Middle Aged , Republic of Korea
4.
Int Nurs Rev ; 64(4): 602-609, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29034970

ABSTRACT

BACKGROUND: Poor oral health is associated with a reduced quality of life and serious illnesses. Consequently, nurses need to be more aware of oral health to improve the general health of residents in care. AIM: To evaluate and compare oral health behaviours and levels of salivary haemoglobin and dental biofilm acidogenicity, which can be used to evaluate oral disease activity, between residents and community dwellers in South Korea. METHODS: This cross-sectional study included 133 participants: 64 residents and 69 community dwellers. All participants completed a questionnaire and tests to measure their salivary haemoglobin and dental biofilm acidogenicity. RESULTS: A higher percentage of community dwellers than of residents brushed their teeth three times a day, cleaned their tongue, used interdental cleaning devices and had visited a dental clinic within 1 year. The levels of salivary haemoglobin and dental biofilm acidogenicity tended to be higher in residents than in community dwellers. CONCLUSION: Residents showed poorer oral health behaviours and higher levels of gingival bleeding and acid production by oral bacteria than did community dwellers. IMPLICATIONS FOR NURSING PRACTICE: Nursing staff should enhance their monitoring of oral hygiene status and provide quality oral care to residents through cooperation with dental professionals. IMPLICATIONS FOR NURSING AND HEALTH POLICY: Policymakers should be aware that oral health is an essential component of improving general health and well-being and therefore strive to develop policies to promote oral care services provided to residents. Nursing policies, such as mandating oral care and hands-on training in oral care for nursing staff, are important. We also suggest that factors related to oral care be added to the establishment or accreditation standards of care facilities.


Subject(s)
Hemoglobins/analysis , Oral Hygiene/nursing , Oral Hygiene/standards , Saliva/chemistry , Stomatognathic Diseases/diagnosis , Stomatognathic Diseases/prevention & control , Tooth/microbiology , Aged , Aged, 80 and over , Biofilms , Cross-Sectional Studies , Female , Humans , Independent Living , Male , Middle Aged , Nursing Homes , Oral Health , Practice Guidelines as Topic , Republic of Korea
5.
Br Poult Sci ; 58(3): 272-277, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28100065

ABSTRACT

1. A dose-response experiment was conducted with male Korean native ducklings (KND) to evaluate the total sulphur amino acid (TSAA) requirement from hatch to 21 d of age. 2. A completely randomised design with 7 dietary TSAA concentrations (0.62%, 0.65%, 0.68%, 0.71%, 0.74%, 0.77% and 0.80%) were used with 6 replications per treatment. 3. Body weight (BW) and feed intake were measured weekly to calculate average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR). One duckling per pen (n = 6) was killed by cervical dislocation to weigh empty body and drumsticks at the conclusion of experiment. 4. BW was improved significantly with increasing TSAA content, in a non-linear manner. A significant decrease of FCR was shown with increasing TSAA contents. TSAA requirement was determined by taking a mean value after fitting the data to both a linear-plateau and a quadratic-plateau model. Estimated TSAA requirements were 0.70%, 0.70%, 0.66% and 0.70% for the maximum BW, ADG and ADFI and for the minimum FCR, respectively. Increasing TSAA content improved quantity of full body weight (FBW), empty body weight (EBW) and drumstick weight (DSW), but there was no effect on proportion of DSW in relation to EBW and proportion of EBW to FBW. 5. In conclusion, the growth of male KND during 1 to 21 d of age was improved with increasing TSAA content, suggesting optimal TSAA requirements estimated by two analysis models.


Subject(s)
Amino Acids, Sulfur/metabolism , Ducks/physiology , Energy Metabolism , Nutritional Requirements , Weight Gain , Animal Feed/analysis , Animals , Diet/veterinary , Dose-Response Relationship, Drug , Ducks/genetics , Ducks/growth & development , Male , Random Allocation
6.
Int Nurs Rev ; 63(1): 33-40, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26549315

ABSTRACT

AIM: The aim of this study was to assess the effects of team-building on communication and teamwork (i.e. teamwork skills and team effectiveness) among nursing students. BACKGROUND: Team-building is effective for improving communication and teamwork among the nursing organization. However, the effects of team-building are not well known especially in Korea. METHODS: This study used a quasi-experimental design. The sample was composed of 195 junior-year nursing students in Korea. The experimental group (100 subjects) participated in team-building activities over a 100-day period, whereas no intervention was applied to the control group (95 subjects). Pretest was conducted in both groups, and post-test was conducted after the 100-day intervention. FINDINGS: The pre-post change in mean communication competence score did not differ between the two groups. However, the mean scores for teamwork skills and team effectiveness differed significantly between the two groups after team-building activity. LIMITATIONS: This study was not a double-blind test, and randomized sampling was not implemented. Caution should thus be used when interpreting the findings. CONCLUSION: Team-building activities were effective for improving the teamwork skills and team effectiveness among Korean nursing students. IMPLICATIONS FOR NURSING EDUCATION: It is recommended that team-building activities should be included regularly as an integral educational approach in nursing education. The findings suggest that suggests that team-building for improving communication and teamwork should be designated as one of the required criteria for nursing college programme accreditation in many countries, including Korea. However team-building requires further testing to verify this across cultures. IMPLICATIONS FOR NURSING POLICY: Nurses need to receive formal team-building training for improving communication and teamwork, and formal education should be included in their job training schedule. It is recommended that communication competence and teamwork be used as one of job performance evaluations in their workplace.


Subject(s)
Communication , Cooperative Behavior , Curriculum , Education, Nursing, Baccalaureate/organization & administration , Students, Nursing/psychology , Adult , Double-Blind Method , Female , Humans , Male , Republic of Korea , Young Adult
7.
Vet Pathol ; 52(6): 1258-62, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25689989

ABSTRACT

Siniperca chuatsi rhabdovirus (SCRV) is one of myriad rhabdoviruses recorded in fish. Preliminary data show that inhibition of the SCRV nucleoprotein (N) could significantly reduce the progeny virus titers in infected Epithelioma papulosum cyprinid (EPC) cells. Here, the authors propose that cleavage of the viral 47-kDa N protein is caspase-mediated based on caspase inhibition experiments, transient expression in EPC transfection, and analysis of cleavage sites. Cleavage of the SCRV N protein in culture was prevented by a pan-caspase inhibitor, z-VAD-FMK (z-Val-Ala-DL-Asp-fluoromethyl ketone). Subsequently, N was transiently expressed in EPC cells, the results of which indicated that the specific cleavage of N also occurred in the cells transfected with N-GFP plasmid. Several truncated fragments of the N gene were constructed and transiently transfected into EPC cells. Immunoblotting results indicated that D324 and D374 are the cleavage sites of N by caspases. The authors also found that z-VAD-FMK could inhibit the cytopathic effect in SCRV-infected EPC cells but not affect the production of infectious progeny, suggesting that the caspase-mediated cleavage of N protein is not required for in vitro SCRV replication. To the authors' knowledge, this is the first report on the cleavage of rhabdovirus proteins.


Subject(s)
Amino Acid Chloromethyl Ketones/pharmacology , Caspase Inhibitors/pharmacology , Caspases/metabolism , Fish Diseases/virology , Nucleoproteins/metabolism , Rhabdoviridae/metabolism , Animals , Apoptosis , Caspases/genetics , Fishes , Genes, Reporter , Proteolysis/drug effects , Viral Proteins/metabolism , Virus Replication/drug effects
8.
Int Nurs Rev ; 62(1): 47-53, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25545743

ABSTRACT

AIM: The purpose of this study was to examine the effects of an individual's motivational needs on team performance, centering on the needs for affiliation, power and achievement, following the McClelland's Achievement Motivation Theory. BACKGROUND: Most previous studies related to McClelland's Achievement Motivation Theory have focused on achievement motivation as a predictor of team performance. In contrast, affiliation and power motivations were relatively little known in connection with team performance. METHODS: This was a descriptive, cross-sectional study using data from 181 junior nursing students in Korea. Data were collected from a questionnaire when the subjects' teamwork task was completed in November 2013. Multiple regression analysis was used to examine the influence of motivational needs on team performance. FINDING: Each group having high levels of the need for affiliation, or the need for power and/or the need for achievement showed a significantly high level of teamwork skills and team effectiveness. The factors influencing teamwork skills were the need for affiliation and the need for achievement. Additionally, the factors influencing team effectiveness were also the need for affiliation and the need for achievement. CONCLUSION: The study reconfirmed the positive influence of the need for achievement, which was the focus of most previous research, in regard to personal and organizational growth. Furthermore, it identified that the need for affiliation, another type of internal motive, positively affected team performance as well. IMPLICATIONS FOR NURSING AND HEALTH POLICY: Nursing schools and nursing organizations should pay attention to their members' affiliation and achievement needs to enhance organizational efficiencies. Through efforts such as developing diverse continuing education programmes for need training, they could enhance their members' needs for affiliation or achievement and consequently increase nursing team performance.


Subject(s)
Achievement , Cooperative Behavior , Education, Nursing, Baccalaureate/organization & administration , Health Knowledge, Attitudes, Practice , Motivation , Students, Nursing/psychology , Adult , Cross-Sectional Studies , Female , Humans , Male , Republic of Korea , Surveys and Questionnaires , Young Adult
9.
Domest Anim Endocrinol ; 42(1): 50-62, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22032857

ABSTRACT

Porcine oocyte-cumulus complexes (OCCs) form an expanded cumulus extracellular matrix (ECM) in response to gonadotropins during meiotic maturation. Essential components of ECM are hyaluronan (HA), tumor necrosis factor α-induced protein 6 (TNFAIP6) and heavy chains (HC) of interalpha-trypsin inhibitor. To form expanded cumulus ECM, intermediate complexes (TNFAIP6-HC) must bind to HA to allow HC transfer onto HA. Protein turnover by the ubiquitin-proteasome pathway is poorly characterized in this process. It is known that the specific proteasomal inhibitor MG132 prevents cumulus expansion and formation of ECM. To determine whether inhibition of proteasomal proteolysis with MG132 affects cumulus cell steroidogenesis and expression of the cumulus expansion-related components (hyaluronan synthase type 2, HAS2, TNFAIP6) we cultured porcine OCCs and granulosa cells (GCs) in a medium supplemented with FSH/LH. Methods performed included real-time reverse transcription PCR, immunofluorescence and RIAs. The expression of TNFAIP6 and HAS2 transcripts increased significantly after the stimulation of OCCs and GCs with FSH/LH. In contrast, treatment with MG132 reduced the expression of TNFAIP6 and HAS2. Hyaluronan was detected with biotinylated HA-binding proteins within FSH/LH-stimulated expanded OCCs but not in those treated with MG132. Progesterone production, although increased almost three times after OCCs stimulation with FSH/LH, was significantly suppressed by MG132. The FSH/LH-stimulated a 40-fold increase in progesterone secretion by GCs was inhibited in the presence of MG132. In conclusion, MG132 affects progesterone secretion and expression of cumulus expansion-related components by cumulus and GCs, suggesting the requirement of ubiquitin-proteasome pathway-regulated protein turnover for formation of ECM during cumulus expansion in the preovulatory period in the pig.


Subject(s)
Cumulus Cells/metabolism , Extracellular Matrix/metabolism , Oocytes/metabolism , Progesterone/biosynthesis , Proteasome Inhibitors , Animals , Cell Adhesion Molecules/biosynthesis , Cumulus Cells/drug effects , Cysteine Proteinase Inhibitors/pharmacology , Extracellular Matrix/drug effects , Female , Leupeptins/pharmacology , Oocytes/drug effects , Proteasome Endopeptidase Complex/metabolism , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction/veterinary , Swine
10.
Int J Androl ; 35(2): 196-210, 2012 Apr.
Article in English | MEDLINE | ID: mdl-21950462

ABSTRACT

Protein ubiquitination is a stable, covalent post-translational modification that alters protein activity and/or targets proteins for proteolysis by the 26S proteasome. The E1-type ubiquitin-activating enzyme (UBA1) is responsible for ubiquitin activation, the initial step of ubiquitin-protein ligation. Proteasomal proteolysis of ubiquitinated spermatozoa and oocyte proteins occurs during mammalian fertilization, particularly at the site of sperm acrosome contact with oocyte zona pellucida. However, it is not clear whether the substrates are solely proteins ubiquitinated during gametogenesis or if de novo ubiquitination also occurs during fertilization supported by ubiquitin-activating and -conjugating enzymes present in the sperm acrosome. Along this line of inquiry, UBA1 was detected in boar sperm-acrosomal extracts by Western blotting (WB). Immunofluorescence revealed accumulation of UBA1 in the nuclei of spermatogonia, spermatocytes and spermatids, and in the acrosomal caps of round and elongating spermatids. Thiol ester assays utilizing biotinylated ubiquitin and isolated sperm acrosomes confirmed the enzymatic activity of the resident UBA1. A specific UBA1 inhibitor, PYR-41, altered the remodelling of the outer acrosomal membrane (OAM) during sperm capacitation, monitored using flow cytometry of fluorescein isothiocyanate-conjugated peanut agglutinin (FITC-PNA). Although viable and motile, the spermatozoa capacitated in the presence of PYR-41, showed significantly reduced fertilization rates during in vitro fertilization (IVF; p < 0.05). Similarly, the fertilization rate was lowered by the addition of PYR-41 directly into fertilization medium during IVF. In WB, high Mr bands, suggestive of protein ubiquitination, were detected in non-capacitated spermatozoa by antibodies against ubiquitin; WB with anti-phosphotyrosine antibodies and antibodies against acrosomal proteins SPINK2 (acrosin inhibitor) and AQN1 (spermadhesin) revealed that the capacitation-induced modification of those proteins was altered by PYR-41. In summary, it appears that de novo protein ubiquitination involving UBA1 contributes to sperm capacitation and acrosomal function during fertilization.


Subject(s)
Acrosome/physiology , Fertilization , Sperm Capacitation , Sperm-Ovum Interactions , Swine/physiology , Ubiquitin-Activating Enzymes/metabolism , Acrosome/immunology , Acrosome Reaction , Animals , Antibodies/immunology , Benzoates/pharmacology , Exocytosis , Fertilization/drug effects , Furans/pharmacology , Glycoproteins/analysis , Glycoproteins/immunology , Male , Phosphotyrosine/immunology , Pyrazoles/pharmacology , Seminal Plasma Proteins/analysis , Seminal Plasma Proteins/immunology , Serine Peptidase Inhibitors, Kazal Type , Spermatocytes/metabolism , Spermatogonia/metabolism , Spermatozoa/metabolism , Swine/metabolism , Ubiquitin/immunology , Ubiquitination , Zona Pellucida/metabolism
11.
J Cell Physiol ; 217(2): 529-43, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18636550

ABSTRACT

Mitochondrial transcription factor A (TFAM) is responsible for stability, maintenance, and transcriptional control of mitochondrial DNA (mtDNA). We have studied the expression and distribution of TFAM in the gametes and preimplantation embryos of the domestic pig (Sus scrofa). We hypothesized that TFAM is not present in the boar sperm mitochondria to reduce the possibility of paternal mtDNA propagation in the progeny. In contrast, we anticipated that Tfam gene is expressed in a developmental stage-dependent manner in porcine oocytes and embryos. The appropriate TFAM band of 25 kDa was detected by Western blotting in ejaculated boar spermatozoa, as well as in porcine oocytes and zygotes. Boar sperm extracts also displayed several bands >25 kDa suggestive of post-translational modification by ubiquitination, confirmed by affinity purification of ubiquitinated proteins. TFAM immunoreactivity was relegated to the sperm tail principal piece and sperm head in fully differentiated spermatozoa. The content of Tfam mRNA increased considerably from the germinal vesicle to blastocyst stage and also between in vitro fertilized and cultured blastocysts compared to in vivo-derived blastocysts. TFAM protein accumulated in the oocytes during maturation and was reduced by proteolysis after fertilization. This pattern was not mirrored in parthenogenetically activated oocytes and zygotes reconstructed by SCNT, suggesting deviant processing of TFAM protein and transcript after oocyte/embryo manipulation. Thus, TFAM may exert a critical role in porcine gametogenesis and preimplantation embryo development. Altogether, our data on the role of TFAM in mitochondrial function and inheritance have broad implications for cell physiology and evolutionary biology.


Subject(s)
Blastocyst/metabolism , Mitochondria/metabolism , Mitochondrial Proteins/metabolism , Oocytes/metabolism , Oogenesis , Spermatogenesis , Spermatozoa/metabolism , Transcription Factors/metabolism , Animals , Blotting, Western , Chromatography, Affinity , DNA, Mitochondrial/metabolism , Embryonic Development , Female , Gene Expression Regulation, Developmental , Male , Meiosis , Mitochondrial Proteins/genetics , Nuclear Transfer Techniques , Parthenogenesis , Protein Processing, Post-Translational , RNA, Messenger/metabolism , Sperm Head/metabolism , Sperm Tail/metabolism , Sus scrofa , Transcription Factors/genetics , Ubiquitin/metabolism , Zygote/metabolism
12.
Anim Reprod Sci ; 103(3-4): 304-11, 2008 Jan 30.
Article in English | MEDLINE | ID: mdl-17215095

ABSTRACT

The present studies were carried out to investigate the effects of intensity of dc pulse, number of dc pulse and equilibration before fusion/activation on developmental ability of porcine embryos derived from nuclear transfer. In experiment 1, different fusion/activation intensity (two dc pulses of 0.4, 0.8, 1.2, 1.6 and 2.0 kV/cm for 30 micros, respectively) was carried out to investigate development of embryos. In experiment 2, the reconstructed oocytes were fused and activated with one, two or three dc pulses of 1.2 kV/cm for 30 micros. In experiment 3, reconstructed oocytes were equilibrated in TCM-199 medium for 0-6 h, respectively, and fused/activated with one dc pulse of 1.2 kV/cm for 30 micros. The reconstructed embryos were cultured in PZM-3 medium containing 0.3% BSA. When oocytes were fused with donor cell by two dc pulses of 0.4 kV/cm for 30 micros, the rates of cleavage and blastocyst formation were significantly lower (32.9% and 2.5%) than those of fused by 0.8 kV/cm (59.0% and 17.4%) or 1.2 kV/cm (63.3% and 18.4%), respectively. One dc pulse of 1.2 kV/cm for 30 micros was enough to fuse and activate embryos to develop to blastocyst (24.8%). Equilibration for 2-3 h in TCM-199 before fusion/activation was beneficial for improving the developmental ability of embryos produced by nuclear transfer (25.6-23.3% at blastocysts).


Subject(s)
Embryonic Development/physiology , Fibroblasts/physiology , Nuclear Transfer Techniques/veterinary , Swine/embryology , Animals , Electric Stimulation , Female , Time Factors
13.
Reproduction ; 132(3): 423-34, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16940283

ABSTRACT

Centrin is an evolutionarily conserved 20 kDa, Ca+2-binding, calmodulin-related protein associated with centrioles and basal bodies of phylogenetically diverse eukaryotic cells. Earlier studies have shown that residual centrosomes of non-rodent mammalian spermatozoa retain centrin and, in theory, could contribute this protein for the reconstruction of the zygotic centrosome after fertilization. The present work shows that CEN2 and CEN3 mRNA were detected in germinal vesicle-stage (GV) oocytes, MII oocytes, and pre-implantation embryos from the two-cell through the blastocyst stage, but not in spermatozoa. Boar ejaculated spermatozoa possess centrin as revealed by immunofluorescence microscopy and western blotting. Immature, GV oocytes possess speckles of centrin particles in the perinuclear area, visualized by immunofluorescence microscopy and exhibit a 19 kDa band revealed by western blotting. Mature MII stage oocytes lacked centrin that could be detected by immunofluorescence or western blotting. The sperm centrin was lost in zygotes after in vitro fertilization. It was not detectable in embryos by immunofluorescence microscopy until the late blastocyst stage. Embryonic centrin first appeared as fine speckles in the perinuclear area of some interphase blastocyst cells and as putative centrosomes of the spindle poles of dividing cells. The cells of the hatched blastocysts developed centrin spots comparable with those of the cultured cells. Some blastomeres displayed undefined curved plate-like centrin-labeled structures. Anti-centrin antibody labeled interphase centrosomes of cultured pig embryonic fibroblast cells as distinct spots in the juxtanuclear area. Enucleated pig oocytes reconstructed by electrofusion with pig fibroblasts displayed centrin of the donor cell during the early stages of nuclear decondensation but became undetectable in the late pronuclear or cleavage stages. These observations suggest that porcine zygotes and pre-blastocyst embryonic cells lack centrin and do not retain exogenously incorporated centrin. The early embryonic centrosomes function without centrin. Centrin in the blastocyst stage embryos is likely a result of de novo synthesis at the onset of differentiation of the pluripotent blastomeres.


Subject(s)
Blastocyst/chemistry , Calcium-Binding Proteins/analysis , Chromosomal Proteins, Non-Histone/analysis , Embryonic Development/physiology , Swine/physiology , Zygote/chemistry , Animals , Blotting, Western/methods , Calcium-Binding Proteins/genetics , Cells, Cultured , Centrosome/metabolism , Chromosomal Proteins, Non-Histone/genetics , Cloning, Organism , Female , Fluorescent Antibody Technique , Male , Microscopy, Fluorescence , Oocytes/chemistry , Oocytes/metabolism , RNA, Messenger/analysis , Reverse Transcriptase Polymerase Chain Reaction , Sperm Injections, Intracytoplasmic , Spermatozoa/chemistry , Spermatozoa/metabolism
14.
Anim Reprod Sci ; 90(1-2): 111-6, 2005 Nov.
Article in English | MEDLINE | ID: mdl-15894439

ABSTRACT

This study was carried out to investigate the effects of teat number and interval at first estrus and mating on litter size in Duroc, Landrace and Yorkshire gilts. Gilt body weight at first estrus was from 101.5 kg to 115.3 kg and gilts normally attained puberty at 170.5-181.5 days of age. Breed differences among Duroc, Landrace and Yorkshire in body weight and age at first estrus and mating were found. Total teat number of Duroc, Landrace and Yorkshire were 12.5, 14.9 and 13.7, respectively. Teat interval from pectoral to inguinal region and from left to right at first estrus and mating did not show any differences among the breeds. In conclusion, 14 or more teat number compared to 11-13 teat number in gilts increased litter size at birth and at 21 day weaning.


Subject(s)
Litter Size , Mammary Glands, Animal/anatomy & histology , Swine , Aging , Animals , Body Weight , Copulation , Estrus , Female , Species Specificity , Time Factors , Weaning
15.
Anim Reprod Sci ; 86(3-4): 297-304, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15766807

ABSTRACT

This study was carried out to investigate the various concentrations and exposure times of ethanol, one of many intracellular calcium elevating agents, and a sequential combination of ethanol (8%), cycloheximide (CHX, 10 microg/ml), cytochalasin B (CCB, 7.5 microg/ml) and 6-dimethylaminopurine (6-DMAP, 2 mM) to improve parthenogenetic activation and development of in vitro matured porcine oocytes. Cumulus-oocyte complexes (COCs) were matured in tissue culture medium (TCM) 199 for 44 h at 38.5 degrees C, 5% CO2 in air. Cumulus-free oocytes showing first polar body were activated by concentrations of 0, 5, 6, 7, 8, 9 and 10% ethanol for 10 min and exposure times of 0, 5, 8, 10, 12 and 15 min with 8% ethanol in HEPES buffered (25 mM) NCSU-23 medium. Also, oocytes were activated with the NCSU-23 medium containing 8% ethanol for 10 min. After that, oocytes were incubated in the NCSU-23 medium supplemented with CHX, CCB, 6-DMAP, CHX + CCB, CHX + 6-DMAP, CCB + 6-DMAP and CHX + CCB + 6-DMAP for 3h, respectively. Following activation, oocytes were transferred into the NCSU-23 medium containing 0.4% BSA for further culture of 20 and 144 h at 38.5 degrees C, 5% CO2 in air. The activation rates of oocytes were higher in 6, 7 and 8% ethanol concentrations compared with 0, 5, 9 and 10% ethanol concentrations. Significantly, more oocytes (29.3-33.7%) were activated in the exposure for 8, 10, 12 and 15 min than those in the exposure for 0 and 5 min, but there was no difference due to exposure to 8% ethanol for 8-15 min. Oocytes treated by chemical agents (40.5-70.5%) after exposure to ethanol significantly improved the rate of oocyte activation compared with ethanol alone (31.2%). The percentage of cleaved oocytes was higher in the ethanol+CHX+CCB+6-DMAP treatment (66.4%) than in other treatments (24.9-57.6%). Also, the rate of blastocyst formation was higher in the ethanol+CHX+CCB+6-DMAP treatment (25.0%) than in other treatments (0.0-19.3%). In conclusion, the optimal activation treatment of ethanol exposure alone for the in vitro matured porcine oocytes was 8% ethanol for 8-15 min. Oocytes activated by 8% ethanol for 10 min and incubated in the NCSU-23 medium supplemented with CHX, CCB and 6-DMAP for 3 h were more efficient for parthenogenetic development of in vitro matured porcine oocytes.


Subject(s)
Adenine/analogs & derivatives , Adenine/pharmacology , Cycloheximide/pharmacology , Cytochalasin B/pharmacology , Ethanol/pharmacology , Oocytes/drug effects , Parthenogenesis/drug effects , Adenine/administration & dosage , Animals , Blastocyst/physiology , Cleavage Stage, Ovum/physiology , Cycloheximide/administration & dosage , Cytochalasin B/administration & dosage , Ethanol/administration & dosage , Female , Oocytes/physiology , Swine
16.
Anim Reprod Sci ; 74(3-4): 187-94, 2002 Dec 16.
Article in English | MEDLINE | ID: mdl-12417120

ABSTRACT

These experiments were carried out to investigate the effect of N-acetyl-D-glucosamine, and to obtain additional information about the effect of orvus es paste (OEP) and egg yolk concentration in the freezing of boar sperm in the maxi-straw. The highest post-thaw acrosomes of normal apical ridge (NAR) and motility were obtained with 0.025 or 0.05% N-acetyl-D-glucosamine concentration in the first diluent. However, there were no effects of N-acetyl-D-glucosamine among the diluents with or without N-acetyl-D-glucosamine at the second dilution. The N-acetyl-D-glucosamine in the first and second diluents was added at room temperatures (20-23 degrees C) and 5 degrees C, respectively. It is suggested that the temperature of N-acetyl-D-glucosamine addition is important for the effect of boar sperm protection during freezing and thawing. When the 0.05% N-acetyl-D-glucosamine was supplemented in the first diluent, the optimum final OEP content was 0.5%. The optimum content of egg yolk in the diluent with 0.05% N-acetyl-D-glucosamine concentration was 20% and egg yolk was one of the main cryoprotective agents. In conclusion, we found out that the diluent with 0.025 or 0.05% soluble N-acetyl-D-glucosamine in the first diluent, 0.5% final orvus es paste concentration and 20% egg yolk concentration significantly enhanced NAR acrosomes and motility of boar sperm after freezing and thawing.


Subject(s)
Acetylglucosamine/pharmacology , Cryopreservation/veterinary , Semen Preservation/veterinary , Spermatozoa , Swine/physiology , Acrosome/metabolism , Animals , Cryopreservation/methods , Egg Yolk/metabolism , Male , Semen Preservation/methods , Sperm Motility/drug effects , Sperm Motility/physiology , Surface-Active Agents/pharmacology
17.
J Oral Rehabil ; 29(9): 816-22, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12366534

ABSTRACT

This in vitro study evaluated the effect of tooth brushing and thermal cycling on the surface lustre and surface roughness of three ceromer systems treated with different surface finishing methods. The ceromers studied were: (1). Artglass, (2). Targis, (3). Sculpture and (4). the control group, Z 100. Half of the Targis and Sculpture groups were polished and the rest were coated with staining and glazing solution, respectively. All specimens were subjected to thermocycling 10000 times. Tooth brushing abrasion tests were performed in a customized tooth-brushing machine with 500 g weight applied on a back-and-forth cycle for 20000 repetitions. The lustre determined by measuring the light reflection area and the average roughness was compared between groups and between pre- and post-test values. All materials showed a lower lustre and rougher surface after thermocycling and tooth brushing (P < 0.05). All ceromer specimens, except glazed Sculpture, showed a higher lustre and similar roughness to the control group. The post-brushing results revealed that glazed Sculpture presented discretely fallen out glaze coatings and had maximum change. However, stained Targis showed minimum change (P < 0.05) and polished Targis presented more changes than that of the staining treatment. It is therefore concluded that the glaze coatings for Sculpture don't exhibit long-term durability, while stain coatings for Targis acted like a protective layer.


Subject(s)
Ceramics , Composite Resins , Dental Polishing , Toothbrushing , Analysis of Variance , Glass Ionomer Cements , Hot Temperature , Materials Testing , Microscopy, Electron, Scanning , Silicate Cement , Silicon Dioxide , Surface Properties , Zirconium
18.
Anim Reprod Sci ; 73(1-2): 53-61, 2002 Sep 16.
Article in English | MEDLINE | ID: mdl-12220818

ABSTRACT

This study was carried out to investigate the effects of Duroc and Yorkshire boars and seasons influencing semen characteristics, frozen-thawed sperm viability and serum testosterone concentration. Yorkshire boars produced higher semen volume compared to Duroc boars among seasons. However, sperm concentration did not differ significantly between Duroc and Yorkshire boars among seasons. Sperm motility of frozen-thawed sperm in Yorkshire boars was higher than in Duroc boars in spring and summer. Normal acrosome of frozen-thawed sperm in Yorkshire boars was higher than in Duroc boars in winter. Serum testosterone concentrations in Duroc and Yorkshire boars were higher in spring than in summer, autumn and winter. Serum testosterone concentrations in spring and summer were higher in Yorkshire boars than in Duroc boars. In conclusion, when serum testosterone concentrations were higher in Duroc and Yorkshire boars among seasons, semen volume, sperm concentration and frozen-thawed sperm viability were higher.


Subject(s)
Semen Preservation/veterinary , Semen/physiology , Swine/genetics , Swine/physiology , Testosterone/blood , Animals , Male , Seasons , Semen/cytology , Semen Preservation/standards , Specimen Handling/veterinary , Sperm Count/veterinary , Sperm Motility
19.
Anim Reprod Sci ; 69(1-2): 91-7, 2002 Jan 23.
Article in English | MEDLINE | ID: mdl-11755720

ABSTRACT

A series of experiments were conducted to determine the effect of N-acetyl-D-glucosamine, glycerol concentration and equilibration time for the freezing of boar spermatozoa in 5 ml maxi-straws. The optimum final glycerol concentration in the diluent with 0.05% N-acetyl-D-glucosamine in the first diluent was 2-3% and the optimum glycerol equilibration time was 2-3h. In conclusion, we recommend the first diluent containing 11% lactose hydrate, 20% egg yolk and 0.05% N-acetyl-D-glucosamine in 100ml distilled water, and the second diluent containing 11% lactose hydrate, 20% egg yolk, 4% glycerol and 1% orvus es paste for the diluents of boar sperm freezing. Also, we found out that 0.05% soluble N-acetyl-D-glucosamine was the optimum concentration in the first diluent and a concentration of 0.05% soluble N-acetyl-D-glucosamine significantly enhanced the cryopreservation of boar spermatozoa.


Subject(s)
Acetylglucosamine/pharmacology , Cryoprotective Agents/pharmacology , Glycerol/pharmacology , Semen Preservation/veterinary , Spermatozoa/cytology , Acetylglucosamine/administration & dosage , Acrosome/drug effects , Acrosome/ultrastructure , Animals , Cryoprotective Agents/administration & dosage , Glycerol/administration & dosage , Male , Sperm Motility/drug effects , Spermatozoa/drug effects , Swine , Time Factors
20.
Bioorg Med Chem Lett ; 10(14): 1589-91, 2000 Jul 17.
Article in English | MEDLINE | ID: mdl-10915058

ABSTRACT

5/6-Arylamino-4,7-dioxobenzothiazoles were synthesized and tested for in vitro antifungal activities against pathogenic fungi. Most of the tested 4,7-dioxobenzothiazoles exhibited potent antifungal activities against Candida species and Aspergillus niger.


Subject(s)
Antifungal Agents/chemical synthesis , Aspergillus niger/drug effects , Candida/drug effects , Thiazoles/chemical synthesis , Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Candida albicans/drug effects , Cell Survival/drug effects , Drug Design , Humans , Microbial Sensitivity Tests , Molecular Structure , Structure-Activity Relationship , Thiazoles/chemistry , Thiazoles/pharmacology , Tumor Cells, Cultured
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