188 research outputs found

    Challenges for the professions in promoting the goals of the RDP

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    The dawning of the new South Africa means different things to different people. To some it means the libera­tion of the individual from restrictions, to others it means the full development of each human being. Many see it as enhancing their standard of living, while others see it as the dawn of full democracy. However, to those involved in archi­tecture, planning, engineering and surveying, such as those in your professions, it presents a great chal­lenge. This challenge is translated into the way in which the professions will contribute towards the delivery of tangible services to a large section of the population through, amongst oth­ers, promoting the goals of the Gov­ernment of National Unity’s Recon­struction and Development Programme (RDP)

    The influence of HIV-1 genomic target region selection and sequence length on the accuracy of inferred phylogenies and clustering outcomes.

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    Masters Degree. University of KwaZulu-Natal, Durban.To improve the methodology of HIV-1 cluster analysis, we addressed how analysis of HIV-1 clustering is associated with parameters that can affect the outcome of viral clustering. The extent of HIV clustering, tree certainty, subtype diversity ratio (SDR), subtype diversity variance (SDV) and Shimodaira-Hasegawa (SH)-like support values were compared between 2881 HIV-1 full genome sequences and sub-genomic regions of which 2567 were retrieved from the LANL HIV Database and 314 were sequenced from blood samples from a cohort in KwaZulu-Natal. Sliding window analysis was based on 99 windows of 1000 bp, 45 windows of 2000 bp and 27 windows of 3000 bp. Clusters were enumerated for each window sequence length, and the optimal sequence length for cluster identification was probed. Potential associations between the extent of HIV clustering and sequence length were also evaluated. The phylogeny based on the full-genome sequences showed the best tree accuracy; it ranked highest with regards to both tree certainty and SH-like support. Product 4, a region associated with env, had the best tree accuracy among the sub-genomic regions. Among the HIV-1 structural genes, env had the best tree certainty, SH-like support, SDR score and the best SDV score overall. The hierarchy of cluster phylotype enumeration mirrored the tree accuracy analysis, with the full genome phylogeny showing the highest extent of clustering, and the product 4 region being second best. Among the structural genes, the highest number of phylotypes was enumerated from the pol phylogeny, followed by env. The extent of HIV-1 clustering was slightly higher for sliding windows of 3 000 bp than 2000 bp and 1000 bp, thus 3000 bp was found to be the optimal length for phylogenetic cluster analysis. We found a moderate association between the length of sequences used and proportion of HIV sequences in clusters; the influence of viral sequence length may have been diminished by the substantial number of taxa. Full-genome sequences could provide the most informative HIV cluster analysis. Selected sub-genomic regions with the best combination of high extent of HIV clustering and high tree accuracy, such as env, could also be considered as a second choice

    Lecturers’ experiences in the implementation of the National Certificate (Vocational) Engineering curriculum in a selected Technical Vocational Education and Training college

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    Abstract is in English, Zulu and AfrikaansSouth Africa is facing a challenge regarding the shortage of South African (SA) engineers. The National Certificate (Vocational) (NC(V)) was introduced by Department of Education (DoE) in 2007 to address this challenge. However, there has been a cry and dissatisfaction from the government, industry, community and other stakeholders that NC(V) engineering curriculum is not addressing the shortage of engineers. SA has one engineer per 2 600 people compared to international norms, where one engineer serves 40 people. It has been ten years since the introduction of NC(V) curriculum, SA should not be in this state of importing engineers if the NC(V) engineering is achieving the goals of National Development Plan 2030. Since lecturers are the implementers of the NC(V) engineering curriculum, it was necessary to investigate their experiences in search for improvement of the curriculum and to find out the challenges facing lecturers which are hindering the success of this curriculum. Lecturers, Senior Lecturers and a Head of Department (HoD) as the primary implementers of the engineering curriculum were involved in the study as participants. There were 15 participants for this study who are lecturing in one selected college but at two different campuses which is why the qualitative research approach was employed, making use of a multiple case study. They took part in semi-structured individual interviews and shared their experiences with the researcher. Their experiences revealed that lecturers are experiencing challenges with the implementation of NC(V) engineering curriculum. Their main challenge was the minimum requirement, which is a Grade 9 pass. Their concern was that no matter what they try, a learner who has not mastered Mathematics up to Grade 12 will struggle with engineering subjects. Emanating from this challenge, low attendance rate, low pass rate, low throughput rate and high drop-out rate is experienced by participants every year. One of the aims of the Transformative Learning Theory (used as one of the theories in the theoretical framework) is to allow lecturers to identify challenges and design improvement plans on their own. This study has indicated that Technical Vocational Education and Training (TVET) colleges have challenges that are hindering teaching and learning. It was evident that some lecturers believe that government officials should resolve such challenges. However, on engaging with different lecturers they realised that they have the capacity to address classroom-based challenges. If this can be the case in every college, teaching and learning will improve because that will mean lecturers are focusing on teaching and learning and taking ownership of their subjects and students. The governance challenges, such as reviewing the NC(V) curriculum yearly, provide subject specific training to upskill lecturers and implementing Work Integrated Learning (WIL) in the professional development of lecturers were recommended to be addressed by the Department of Higher Education and Training (DHET).INingizimu Afrika ibhekene nenselelo mayelana nokusweleka konjiniyela. Uhlelo lwemfundo iNational Certificate (Vocational) (NC(V)) lwethulwa wuMnyango wezeMfundo ngonyaka ka 2007 ukuze uxazulule le nkinga. Yize-kunjalo kuye kwaba khona ukungagculiseki ngasohlangothini lukahulumeni, lwezimboni, lomphakathi kanye nakwezinye izinhlaka ezidlala indima yenkinga yokuntuleka konjiniyela. INingizimu Afrika (SA) inonjiniyela oyedwa kubantu abayi 2 600 uma iqhathaniswa nezinga lomhlaba lokuthi unjiniyela oyedwa kufanele ibhekane nabantu abayi 40. Sekudlule iminyaka eyishumi selokhu kwethulwa lezi zinhlelo, ngakho-ke, iSA akufanele izithole isesimeni sokudinga onjiniyela abavela ngaphandle uma ngabe izinhlelo ezikhona ziyanceda ekufinyeleleni izimpokophelo zoHlelo lwezokuThuthukisa iZwe National Development Plan 2030. Njengoba abafundisi bangabaqhubi bezinhlelo zobunjiniyela, phecelezi NC(V), nokho sasikhona isidingo sokuphenya lokho abahlangabezana nakho ukuze kuthuthukiswe izinhlelo futhi kuvunjululwe izinselele ezibhekene nabafundisi, okuyizinselele ezikhinyabeza impumelelo yalezi zinhlelo. Abafundisi, abafundisi abaphezulu kanye neziNhloko zoMnyango Head of Department (HoD) njengabaqhubi bokuqala bezinhlelo bebebambe iqhaza kulolu cwaningo. Abadlalindima abayi 15 bebefundisa kwikholeji ekhethiwe, kodwa emagatsheni amabili ehlukene, lokho okwenza isizathu kusetshenziswe uhlelo locwaningo oluzinze kwizingxoxo, ngokusebenzisa izinhlobonhlobo zocwaningo lotho. Kwenziwe izinhlolovo ezimbaxambili zocwaningo kanti abadlalindima bavezele umcwaningi ulwazi lwabo. Baye baveza ukuthi behlangabezene nezingqinamba uma besebenzisa izinhlelo zobunjiniyela NC(V). Inselele enkulu abahlangabezene nayo kuye kwaba yisidingo sokuphumelela uGreyidi 9. Inkinga enkulu yabo ukuthi bethi bezama ngamandla kulokho abakwenzayo, umfundi owehluleke esifundweni seMethamethiki ukufikela kuGreyidi 12 uzohlangabezana nobunzima ukuze aphumelele ezifundweni zobunjiniyela. Okubhebhethekiswa yile nselele, yizinga eliphansi labafundi abahambela lesi sifundo, izinga eliphansi labafundi abaphumelelayo kanye nezinga eliphezulu labafundi abayeka ukufunda njalo nje ngonyaka. Enye yezinhloso zethiyori yemfundo eguqulayo (used as one of the theories in the theoretical framework) ukuvumela abafundisi ukuba bakwazi ukubona izinselele futhi badizayine izinhlelo zokuzithuthukisa ngokwabo. Lolu cwaningo luye lwaveza ukuthi amakholeji. Phecelezi Vocational Education and Training (TVET) colleges ahlangabezene nezinselele eziphazamisa uhlelo lokufunda nokufundisa. Kuye kwacaca ukuthi abanye abafundisi babekholelwa ekutheni abasebenzi bakahulumeni kufanele baxazulule izinselele ezinjengazo lezi. Yize-kunjalo, ngemuva kokuxoxisana nabafundisi abahlukahlukene, baye bazwisisa ukuthi banamandla okuqeda izinselele ezisemagunjini okufunda. Uma ngabe lokhu kuyenzeka ngempela kuwo wonke amakholeji, ngakho-ke uhlelo lokufunda nokufundisa luzothuthuka ngoba lokho kuzochaza ukuthi abafundisi bagxile ohlelweni lokufunda nokufundisa kanti ngokunjalo baba yibo abalawula izifundo kanye nabafundi babo. Izinselele zokuphatha, ezinjengokubuyekezwa kohlelo lwemfundo, phecelezi NC(V) njalo nje ngonyaka, lunikeza ukuqeqeshwa okuthile okuthuthukisa abafundisi. Ukulandela uhlelo lwemfundo oluhlangene nomsebenzi olumayelana nokuthuthukiswa ngokomsebenzi wabafundisi kuyinto enconywe ukuba ilungiswe uMnyango weMfundo ePhakeme kanye nokuQeqeshwa (Department of Higher Education and Training).ʼn Tekort aan ambagslui staar Suid-Afrika in die gesig. Om hierdie rede het die Departement van Onderwys in 2007 die Nasionale Sertifikaat (Beroepsgerig) (NS(B)) ingestel. Tot die ontevredenheid van die regering, die bedryf, die gemeenskap en ander belanghebbendes vul hierdie kurrikulum nie die tekort aan nie. In Suid-Afrika is daar een ambagspersoon vir elke 2 600 mense teenoor die internasionale norm van een ambagspersoon per 40 mense. Hierdie kurrikulum is meer as tien jaar gelede ingestel en SA moet tans ambagslui invoer. Die oogmerke van die Nasionale Ontwikkelingsplan 2030 word dus nie verwesenlik nie. Aangesien dosente die NS(B) kurrikulum vir werktuigkundiges implementeer, moes hulle belewenisse ondersoek en hulle probleme bepaal word om die kurrikulum te verbeter. Dosente, senior dosente en departementshoofde, as die implementeerders van hierdie kurrikulum, het aan die studie deelgeneem. Die 15 deelnemers is verbonde aan een kollege wat twee kampusse het. Daarom is ʼn kwalitatiewe navorsingsbenadering gevolg en ʼn veelvuldige gevallestudie gebruik. ʼn Halfgestruktureerde onderhoud is met elke deelnemer gevoer. Uit die onderhoude blyk dat dosente moeite met die implementering van die NS(B) kurrikulum ondervind. Die grootste struikelblok is die minimumvereiste van Graad 9. Al doen hulle ook wat, ʼn leerder wat nie Graad 12-wiskunde geslaag het nie, sal tegniese vakke nie kan bemeester nie. Afgesien hiervan is die bywonings- en slaagsyfer sowel as die omset jaar na jaar laag en die uitsaksyfer hoog. Die transformatiewe leerteorie is deel van die teoretiese raamwerk. Die oogmerk hiervan is dat dosente self probleme aantoon en met verbeteringsplanne kom. In hierdie studie is bevind dat kolleges vir tegniese beroepsgerigte onderwys en opleiding (TBOO) met probleme te kampe het wat onderrig en leer belemmer. Sommige dosente is van mening dat staatsamptenare hierdie probleme moet oplos. Ná gesprekke het talle dosente egter besef dat hulle oor die vermoë beskik om self hulle klaskamerprobleme op te los. As dit van alle kolleges waar is, sal onderrig en leer verbeter omdat dosente hulle op onderrig en leer sal toespits en vir hulle vakke en studente verantwoordelik sal wees. Vakopleiding word gegee om aan bestuursprobleme, soos die jaarlikse hersiening van die NS(B)-leerplan, die hoof te bied. Daar word aanbeveel dat die Departement van Hoër Onderwys en Opleiding toesien dat werkgeïntegreerde leer deel uitmaak van dosente se professionele ontwikkeling.Curriculum and Instructional StudiesM. Ed. (Curriculum Studies

    The use of English as the language of learning and teaching to grade one isiZulu-speaking learners

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    The decision by some public primary schools situated in the King Cetshwayo District, in KwaZulu Natal, South Africa, to use English as language of learning and teaching (LoLT) in teaching isiZulu-speaking learners in Grade 1 classrooms, is a matter of concern. English is not the learners’ home language and the practice is also against the policy of the Department of Basic Education. In considering the recommendation by the South African Constitution, Acts and language policies of the country, it is expected to see all Foundation Phase (Grade R-3) learners being taught in their home language. The aim of this study was to explore the use of English as LoLT in teaching Grade 1 isiZulu-speaking learners. The interpretivist/constructivist paradigm underpinned the study as did the Language Acquisition Theory proposed by Skinner and Teacher Efficacy Theory by Bandura. This study adopted a qualitative multiple-case study as it aimed to explore the use of English as the LoLT in teaching Grade 1 isiZulu-speaking learners. One-on-one, semi-structured interviews, observations and document analysis were used as data collection instruments. A purposive sampling of six Grade 1 teachers from three public primary schools was employed. Thematic data analysis method was used to analyse collected data. Data collected were analysed, categorised into codes and themes were identified. Overall, it was found that the communities regard the schools, offering English as the LoLT in teaching Grade 1 IsiZulu-speaking learners, as the best performing schools, though the language policy was not taken into consideration and the teachers are challenged in using the target language in their teaching. It was found that five Grade 1 teachers used English in conjunction with isiZulu and only one teacher used a minimal amount of isiZulu to clarify concepts for learners to understand. It was concluded that some teachers found themselves frustrated in using English as the LoLT due to lack of proper mentoring and support from the School Management Teams (SMTs). It is recommended that the provincial Department of Education, under the leadership of the Member of the Executive Council (MEC), should review the language policy and give some clarity to ensure that schools receive guidance on how to choose the most appropriate LoLT. It is also recommended that the SMTs should provide the proper mentorship programmes, especially for teachers who are new in the school where English is used as the LoLT.Qeto ea likolo tse ling tsa mathomo tsa sechaba tse seterekeng sa King Cetshwayo, KwaZulu-Natal, Afrika Boroa, ho sebelisa Senyesemane e le puo ea ho ithuta le ho ruta (LoLT) ho ruta bana ba buang Senyesemane lihlopheng tsa 1 tsa phapusi, ke taba ea ho ameha. Senyesemane hase puo ea lehae ea liithuti ebile mokhoa ona o khahlanong le leano la Lefapha la thuto ea motheo. Ha re hlahloba khothatso ea Molao-motheo oa Afrika Boroa, Liketso le lipuo tsa puo tsa naha, ho lebeletsoe ho bona liithuti tsohle tsa thuto ea Sehlopha sa Motheo (R-3) li rutoa ka puo ea habo bona. Sepheo sa thuto ena e ne e le ho hlahloba tšebeliso ea Senyesemane joaloka LoLT ho ruta barutoana ba 1 ba buang Senyesemane. Paradigm ea li-interpretivist / constructivist e ile ea tšehetsa thuto joaloka Sephiri sa Thekiso ea Lipuo e hlalositsoeng ke Skinner le Teacher Efficacy Theory ea Bandura. Phuputso ena e ile ea amohela thuto e nang le mekhoa e metle e le hore e hlahlobe tšebeliso ea Senyesemane jwale ka leleme la ho ruta barutoana ba 1 ba buang IsiZulu. E mong le e mong ho ea ho e mong, lipuisano tse sa tšoaneng, litlhaloso le tlhahlobo ea litokomane li ile tsa sebelisoa e le lisebelisoa tsa ho bokella data. Sampula e hloekileng ea basoue ba tšeletseng ba likhaolo ho tloha likolong tse tharo tsa sechaba tsa pele e ne e sebelisoa. Tsela ea ts'ebetso e sebeliselitsoe ho hlahloba lintlha tse bokelitsoeng. Lintlha tse bokelitsoeng li ile tsa hlahlojoa, tsa aroloa ka mekhoa le lihlooho tse fumanoeng. Ka kakaretso, ho fumanoe hore sechaba se nka likolo, se fana ka Senyesemane e le leleme la ho ruta le ho ithuta lithuto tsa mphato wa pele wa barutoana ba Sezulu, e le likolo tse ntle ka ho fetisisa, le hoja polelo ea puo e sa hlokomeloe 'me basoue ba phephetsoa ho sebelisa sepheo puo ha ba ruta. Ho fumanoe hore mesuoe e mehlano ea Bakala 1 e sebelisitse Senyesemane hammoho le Senyesemane mme mosuoe a le mong feela o sebelisitse Senyesemane se fokolang ho hlakisa maikutlo a hore baithuti ba utloisise. Ho ile ha fihleloa qeto ea hore basuoe ba bang ba ile ba iphumana ba tsielehile ha ba sebelisa Senyesemane e le LoLT ka lebaka la ho hloka tataiso e viii nepahetseng le ts'ehetso ea Lihlopha tsa Tsamaiso ea Sekolo. Ho kgothaletswa hore Lefapha la Thuto la profinse, tlas'a boeta-pele ba Lekhotla la Tsamaiso (MEC), le lokela ho hlahloba leano la puo le ho fana ka ho hlaka ho netefatsa hore likolo li fumana tataiso mabapi le mokhoa oa ho khetha LoLT e nepahetseng ka ho fetisisa. Ho boetse ho kgothaletswa hore basebeletsi ba SMTs ba fane ka ts'ebetso e nepahetseng ea ho fana ka ts'ebetso, haholo-holo ho mesuoe e mecha sekolong moo Senyesemane se sebelisoang e le LoLT.Isinqumo sezinye izikole zamabanga aphansi emphakathini wesiyingi iKing Cetshwayo, KwaZulu-Natali, eNingizimu Afrika, sokusebenzisa isiNgisi njengolimi lokufunda nokufundisa (LoLT) ekufundiseni abafundi beBanga 1 abakhuluma isiZulu, kuyindaba yokukhathazeka. IsiNgisi akulona ulimi lwasekhaya lwalaba bafundi kanti futhi lesi senzo siphambene nenqubomgomo yoMnyango Wezemfundo Eyisisekelo. Uma ubhekisisa izincomo zomthethosisekelo waseNingizimu Afrika, imithetho nezinqubomgomo zolimi lwezwe, kulindeleke ukuthi bonke abafundi bamabanga aphansi (Grade R-3) bafundiswe ngolimi lwabo lwasekhaya. Inhloso yalolu cwaningo kwakuwukuhlola ukusetshenziselwa isiNgisi njengolimi lokufunda nokufundisa (LoLT) ekufundiseni abafundi beBanga 1 abakhuluma isiZulu. I-interpretivist / constructivist paradigm yalekelela lolu cwaningo njengoba kwenza i-Language Acquisition Theory ehlongozwa u-Skinner Kanye ne-Teacher Efficacy Theory ka-Bandura. Lesi sifundo sithatha uhlelo lwe qualitative multiple-case study njengoba sihlose ukucwaninga ukusetshenziswa kwesiNgisi njengolimi lokufunda nokufundisa lapho kufundiswa abafundi beBanga 1 abakhuluma isiZulu. Izingxoxo zomuntu nomuntu kusetshenzisw imibuzo ehlelwe kahle, ukubuka lapho kufundiswa kanye nokuhlaziywa kwamabhuku kwasetshenziswa njengamathuluzi okuqoqa ulwazi. Isampula elicacile labafundisi abayisithupha beBanga 1, abavela ezikoleni ezintathu zamabanga aphansi lasetshenziswa. Indlela yokuhlaziya ulwazi ye-Thematic yasetshenziselwa ukuhlaziya ulwazi olwaqoqwa. Ulwazi olwaqoqwa lwahlaziywa, lwahlukaniswa ngamakhodi nezindikimba. Ngokujwayelekile, kwatholakala ukuthi imiphakathi ibheka izikole, ezihlinzeka isiNgisi njengolimi lokufunda nokufundisa (LoLT) ekufundiseni abafundi beBanga 1 abakhuluma IsiZulu, njengezikole ezenza kahle kakhulu, nakuba inqubomgomo yolimi ingabhekiwe futhi othisha behlangabezana nobunzima lapho besebenzisa lolu limi olukhethiwe ekufundiseni kwabo. Kwatholakala ukuthi othisha abahlanu beBanga 1 basebenzisa isiNgisi ngokuhlanganyela nesiZulu kanti uthisha oyedwa kuphela wasebenzisa isiZulu esincane kakhulu lapho ecacisa imibono ukuze abafundi baqonde. Kwatholakala ukuthi abanye othisha bazithola bexakekile lapho besebenzisa isiNgisi njengolimi lokufunda nokufundisa (LoLT) ngenxa yokungatholi ukulekelelwa okufanele kanye nokusekwa amathimba okuphatha izikole (SMTs). Kunconywa ukuthi uMnyango Wezemfundo wesifundazwe, ngaphansi kobuholi beLungu loMkhandlu oPhethe (MEC), ubuyekeze inqubomgomo yolimi, ubuye unikeze izikole inqubo ecacile ukuqinisekisa ukuthi izikole zikhetha ulimi lokufunda nokufundisa ngendlela okuyi yona yona. Kuyanconywa futhi ukuthi amathimba aphethe izikole ahlinzeke ngezinhlelo ezinhle zokulekelela othisa, ikakhulukazi othisha abasha esikoleni lapho isiNgisi sisetshenziswa khona njengolimi lokufunda nokufundisa.Curriculum and Instructional StudiesM. Ed. (Curriculum and Instructional Studies

    An assessment of the implementation of the performance management strategy used by South African breweries in east coast region.

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    Masters Degree. University of KwaZulu-Natal, Durban.Performance management is aimed at constant development of employees, wherein their input to the organization is acknowledged, and their future potential and developmental needs are identified. In other words, performance management aims at expediting an understanding that is shared through giving and receiving feedback with mutual accountability as it were. While so much is known about the performance management itself, little is known with regards to the implementation of the performance management strategy. This study seeks to assess the implementation of the performance management strategy, with special reference to the East Coast region of the South African Breweries. To do this, the study seeks to understand the performance management goals set by the organization, performance measurement and the performance feedback techniques. Similarly, the study seeks to understand the basis of reward for performance and to understand how performance objectives and activities in the organization are implemented. The qualitative research methodology type was employed. In essence, the exploratory research design was utilized, while 12 respondents comprising of managers and employees were purposively selected for the study. The in-depth interview type was used to elicit responses from the respondents. The date cleansing was done with Trcohim and Donnelly (2007) four indicators of reliability and validity of qualitative data, while the thematic qualitative data analysis was employed to analyse the qualitative data. The findings of the study indicate that performance management goals are set from the top and cascaded down throughout the company. These goals are set against company’s performance targets. Similarly, other findings showed that performance measurement are done on a routine basis such weekly, monthly and on annual basis. It was also found that there is one standard feedback system which is tracked every week on a one on one basis which leads to two performance reviews a year. Again, findings showed that reward system for performance is based on achieving performance targets set against KPIs. Lastly, findings exude that performance management decisions are imposed by top management and the goals for individuals are implemented with the aim of achieving their targets. Thus, the study recommend that for a the standardised target strategy due to the fact that there is standard tool of operating performance measurements in different geographical location that have different standards of living and products preferences. The need for a standardized format of providing feedback to employees and Human Resource Management should also in be involved in the process and the consideration of environmental influence in the administration of reward system. Lastly, it is recommended that there must be room for employee’s consultation on issues of performance implementation and employees must be full participants of any implementation strategy

    Stable Densities, Fractional Integrals and the Mittag-Leffler Function

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    This paper combines probability theory and fractional calculus to derive a novel integral representation of the three-parameter Mittag-Leffler function or Prabhakar function, where the three parameters are combinations of four base parameters. The fundamental concept is the Riemann-Liouville fractional integral of the one-sided stable density, conditioned on a scale factor. Integrating with respect to a gamma-distributed scale factor induces a mixture of Riemann-Liouville integrals. A particular combination of four base parameters leads to a representation of the Prabhakar function as a weighted mixture of Riemann-Liouville integrals at different scales. The Prabhakar function constructed in this manner is the Laplace transform of a four-parameter distribution. This general approach gives various known results as special cases (notably, the two-parameter generalised Mittag-Leffler distribution).Comment: 15 page

    Evaluating the effect of nitric oxide on myoblast proliferation, migration and differentiation.

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    Masters Degree. University of KwaZulu-Natal, Pietermaritzburg.Wound healing is the process of restoring tissue integrity in response to injury. This process involves four major phases namely; haemostasis, inflammation, regeneration and remodelling. These phases are regulated by various growth factors and cytokines that are released at the site of injury to facilitate wound repair. Cells involved in wound healing include neutrophils, macrophages, lymphocytes, fibroblasts and stem cells. Satellite cells are mesenchymal stem cells which facilitate skeletal muscle regeneration through a process known as myogenesis. These cells are quiescently located underneath the sarcolemma of the muscle fiber and are activated upon injury to enter the growth phase of cell cycle. They then proliferate and migrate to the injury site to differentiate and fuse with existing fibers to form multinucleated muscle cells.Growth factors and signalling molecules, such as hepatocyte growth factor (HGF) and nitric oxide (NO), induce satellite cell activation by altering the expression of transcription factors such as paired box transcription factor 7 (Pax7), myogenic regulatory factor 5 (Myf5), myogenic differentiation antigen (MyoD) and Myogenin. The role of NO in the subsequent process of myoblast proliferation, migration and differentiation is however unclear. The present study therefore evaluated the effect of nitric oxide on myoblast proliferation, migration and terminal differentiation. C2C12 myoblasts were cultured in standard growth media and subsequently plated for analysis in serum free media. Proliferation or differentiation was induced via the addition of either 2 ng/ml HGF or 2% horse serum respectively, while migration was stimulated using the standard in vitro wound healing assay. L-NAME (a NOS inhibitor; 100 µM and 200 µM) and SIN-1 (a NO donor; 10 µM or 25 µM) were utilized to modify NO levels in vitro, while NO levels were assessed using a nitric oxide colorimetric assay kit. Proliferation was assessed via cell counts, migration by assessing the percentage wound closure and differentiation determined by calculating myoblast alignment and subsequent fusion into multinucleated myotubes. There was no significant change in nitric oxide generated by myoblasts during proliferation and migration studies. However, NO levels increased significantly in response to differentiation, L-NAME significantly prevented this NO increase at day of differentiation. L-NAME also significantly decreased myoblast terminal differentiation by inhibiting myoblast alignment and fusion at day 5 of differentiation. L-NAME also significantly reduced the proliferative effect of HGF on myoblasts at 24 hours, and significantly reduced percentage wound closure at 16 hours post-injury. NO release by C2C12 myoblast was observed to increase in response to SIN-1 in a dose dependent manner. NO levels significantly increased from 0.58 nmol in a control up to 1.35 nmol and 1.9 nmol at 1 hour in response to 10 µM and 25 µM SIN-1 respectively. These levels increased until they reached 2.5 nmol in response to 25 µM SIN-1 at 16 hours. SIN-1 showed no significant effect on myoblast proliferation, however, it significantly promoted myoblast migration in a dose dependent manner by increasing the percentage wound closure to 42% and 45% at 7 hours for 10 µM and 25 µM respectively compared to 38% of the control. SIN-1 also significantly stimulated myoblast fusion with myofiber area of 26% as compared to 18.6% of the control at day 5 of differentiation. In conclusion, nitric oxide levels increase significantly during myoblast differentiation, but not during proliferation and migration. Despite this, inhibition of nitric oxide synthase significantly affects all these processes. In contrast NOS-independent elevation of NO (through incubation with SIN-1) significantly increased myoblast migration and fusion, but not proliferation. This suggests a central role for NO in regulating myogenesis; however, this role requires further investigation
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