Hyperfine-resolved optical spectroscopy of the A2Π â† X2Σ+ transition in MgF.

We report on hyperfine-resolved laser spectroscopy of the A2Π â† X2Σ+ transition of magnesium monofluoride (MgF), relevant for laser cooling. We recorded 25 rotational transitions with an absolute accuracy of better than 20 MHz, assigned 56 hyperfine lines, and determined precise rotational, fine, and hyperfine structure parameters for the A2Π state. The radiative lifetime of the A2Π state was determined to be 7.2(3) ns, in good agreement with ab initio calculations. The transition isotope shift between bosonic isotopologues of the molecule is recorded and compared to predicted values within the Born-Oppenheimer approximation. We measured the Stark effect of selected rotational lines of the A2Π â† X2Σ+ transition by applying electric fields of up to 10.6 kV cm-1 and determined the permanent electric dipole moments of 24MgF in its ground X2Σ+ and first excited A2Π states to be µX = 2.88(20) D and µA = 3.20(22) D, respectively. Based on these measurements, we caution for potential losses from the optical cycling transition due to electric field induced parity mixing in the excited state. In order to scatter 104 photons, the electric field must be controlled to below 1 V cm-1.

The chemistry of AlF and CaF production in buffer gas sources.

In this work, we explore the role of chemical reactions on the properties of buffer gas cooled molecular beams. In particular, we focus on scenarios relevant to the formation of AlF and CaF via chemical reactions between the Ca and Al atoms ablated from a solid target in an atmosphere of a fluorine-containing gas, in this case, SF6 and NF3. Reactions are studied following an ab initio molecular dynamics approach, and the results are rationalized following a tree-shaped reaction model based on Bayesian inference. We find that NF3 reacts more efficiently with hot metal atoms to form monofluoride molecules than SF6. In addition, when using NF3, the reaction products have lower kinetic energy, requiring fewer collisions to thermalize with the cryogenic helium. Furthermore, we find that the reaction probability for AlF formation is much higher than for CaF across a broad range of kinetic temperatures.

'It depends on how the relationship was before you became ill': black South African women's experiences of life partner support through the trajectory of cervical cancer.

Spouses are the primary source of support for married patients and patients suffering from gynaecological cancers and play a major role in the positive, or negative, management of the disease and treatment. The purpose of the study was to explore the experiences of life partner support among hospitalised women receiving treatment for cervical cancer at an academic hospital in Tshwane, South Africa. An exploratory, qualitative study was conducted using a convenience sampling method. Seventeen (n = 17) women were interviewed. The data were analysed using open coding and a template analysis style. The support women treated for cervical cancer received from their life partner varied. Some were fully supported while others received limited support and some were even abandoned. Both the women and their life partners were challenged in terms of giving and receiving support. How the support they received from their life partners influenced their quality of life is not known and should be the next exploratory step before designing and testing a support intervention to maximise the outcomes for these patients.

Combining breast and cervical screening in an attempt to increase cervical screening uptake. An intervention study in a South African context.

During 2008-2009, only 4% of women targeted for cervical screening were screened in Tshwane, South Africa. The purpose of the study was to determine whether cervical screening uptake could be improved when breast and cervical screening are combined. An intervention research design was used. The intervention was assessed in terms of two outcomes, namely cervical screening uptake and the findings of the screening. The study was conducted in a resource poor environment in Tshwane. Convenience sampling was used to recruit the sample (n = 299) and a baseline survey was conducted before delivering the intervention. Only 14% of the sample (n = 299) reported having been screened for cervical cancer previously. The total sample (n = 299) were willing to have a clinical breast examination; however, only 65.4% of those eligible for cervical screening (n = 283) used the opportunity to be screened. The majority of the sample screened (n = 185) using acetic acid for visual inspection (VIA) were VIA negative; 12.4% were VIA positive and 4.4% were VIA positive, invasive cancer; the screening of 8.7% failed. Despite women's lack of knowledge of cervical cancer and the screening thereof, combining cervical screening and breast screening lead to an increase in cervical screening uptake.

Men's lack of knowledge adds to the cervical cancer burden in South Africa.

The purpose of the study was to determine the level of knowledge regarding cervical cancer among Black men living in Ga-Rankuwa, South Africa. A quantitative survey was conducted. The population consisted of 980 (n = 980) convenience sampled men. Self-reported data were gathered using a structured interview and a pre-tested questionnaire served as data gathering instrument. The study provided evidence that men living in Ga-Rankuwa did not have knowledge of cervical cancer. None of the sample mentioned the HPV as risk factor while some knew that having multiple sexual partners add to a woman's risk. It is, however, doubtful whether the respondents experienced themselves as those with the multiple partners. More than 90% of the sample (n = 963) reported to have had more than one sexual partner in the previous 5 years while less than a quarter indicated that they would have to change their sexual behaviour to prevent cervical cancer. Men add to the cervical cancer burden in South Africa as their knowledge would not enable them to protect their partners from HPV infections, motivate them to be screened or allow them to protect themselves against this dreadful disease.

Biochemical pathways of apoptosis: nicotinamide adenine dinucleotide-deficient cells are resistant to tumor necrosis factor or ultraviolet light activation of the 24-kD apoptotic protease and DNA fragmentation.

The function of nicotinamide adenine dinucleotide (NAD) and adenosine diphosphate (ADP) ribosylation reactions in the mechanism of apoptotic cell death is controversial, although one theory postulates an essential role for NAD depletion by poly-ADP-ribose polymerase. The present study examined the role of intracellular NAD in tumor necrosis factor (TNF) and ultraviolet (UV) light-induced activation of the 24-kD apoptotic protease (AP24) leading to internucleosomal DNA fragmentation and death. Our results demonstrate that nutritional depletion of NAD to undetectable levels in two leukemia lines (U937 and HL-60) renders them completely resistant to apoptosis. This was attributed to a block in the activation of AP24 and subsequent DNA cleavage. Normal cells show an elevation of ADP-ribosyl transferase (ADPRT) in both the cytosol and nucleus after exposure to TNF, but before DNA fragmentation. ADPRT activity as well as cell death was suppressed by an inhibitor specific for mono-ADPRT. Nuclei from NAD-depleted cells were still sensitive to DNA fragmentation induced by exogenous AP24, indicating a selective function for NAD upstream of AP24 activation in the apoptotic pathway. We confirmed a requirement for intracellular NAD, activation of ADPRT, and subsequent NAD depletion during apoptosis in KG1a, YAC-1, and BW1547 leukemia cell lines. However, this mechanism is not universal, since BJAB and Jurkat leukemia cells underwent apoptosis normally, even in the absence of detectable intracellular NAD. We conclude that TNF or UV light-induced apoptotic cell death is not due to NAD depletion in some leukemia cell lines. Rather, NAD-dependent reactions which may involve mono-ADPRT, function in signal transduction leading to activation of AP24, with subsequent DNA fragmentation and cell death.

Activation of CPP32-like proteases is not sufficient to trigger apoptosis: inhibition of apoptosis by agents that suppress activation of AP24, but not CPP32-like activity.

The 24-kD apoptotic protease (AP24) is a serine protease that is activated during apoptosis and has the capacity to activate internucleosomal DNA fragmentation in isolated nuclei. This study examined the following: (a) the functional relationship between AP24 and the CPP32-like proteases of the caspase family; and (b) whether activation of CPP32-like proteases is sufficient to commit irreversibly a cell to apoptotic death. In three different leukemia cell lines, we showed that agents that directly (carbobenzoxy-Ala-Ala-borophe (DK120) or indirectly inhibit activation of AP24 (protein kinase inhibitors, basic fibroblast growth factor, tosylphenylalaninechloromethylketone, and caspase inhibitors) protected cells from apoptosis induced by TNF or UV light. Only the caspase inhibitors, however, prevented activation of CPP32-like activity as revealed by cleavage of the synthetic substrate, DEVD-pNa, by cell cytosols, and also by in vivo cleavage of poly (ADP-ribosyl) polymerase, a known substrate of CPP32. Activation of DEVD-pNa cleaving activity without apoptosis was also demonstrated in two variants derived from the U937 monocytic leukemia in the absence of exogenous inhibitors. Cell-permeable peptide inhibitors selective for CPP32-like proteases suppressed AP24 activation and apoptotic death. These findings indicate that CPP32-like activity is one of several upstream signals required for AP24 activation. Furthermore, activation of CPP32-like proteases alone is not sufficient to commit irreversibly a cell to apoptotic death under conditions where activation of AP24 is inhibited.

Purification of a 24-kD protease from apoptotic tumor cells that activates DNA fragmentation.

We report the purification of a protease from tumor cells undergoing apoptosis that is involved in activating DNA fragmentation. Initial studies revealed that two inhibitors of serine proteases, N-1-tosylamide-2-phenylethylchloromethyl ketone and carbobenzoxy-Ala-Ala-borophe (DK120), suppressed tumor necrosis factor or ultraviolet (UV) light-induced DNA fragmentation in the U937 histiocytic lymphoma as well as UV light-induced DNA fragmentation in the BT-20 breast carcinoma, HL-60 myelocytic leukemia, and 3T3 fibroblasts. The protease was purified by affinity chromatography with DK120 as ligand and showed high activity on a synthetic substrate preferred by elastase-like enzymes (Ala-Ala-Pro-Val p-nitroanilide), but was inactive on the trypsin substrate, N-alpha-benzyloxycarbonyl-L-lysine thiobenzyl ester, or the chymotrypsin substrate, Ala-Ala-Pro-Phe p-nitroanilide. The activity of the DK120-binding protease purified from U937 cells undergoing apoptosis was increased approximately 10-fold over that recovered from normal cells. Further purification to homogeneity by heparin-Sepharose affinity chromatography followed by reverse phase high-performance liquid chromatography revealed a single band of 24 kD on a silver-stained sodium dodecyl sulfate gel. In addition to protease activity, the purified enzyme induced DNA fragmentation into multiples of 180 basepairs in isolated U937 nuclei. These findings suggest the 24-kD protease is a novel enzyme that activates DNA fragmentation in U937 cells undergoing apoptosis.

Knowledge related to nutrition and hypertension management practices of adults in Ga-Rankuwa day clinics.

Hypertension is a global, non-communicable chronic disease being asymptomatic and known as the silent killer with signs and symptoms only occurring when a target organ is damaged. Being a condition common in South Africa, hypertension is also a risk factor for cerebro-vascular incidents, myocardial infarction, left ventricular hypertrophy, renal disease and retinopathy. Black adults in an urban environment appear to be especially vulnerable to excessive increases in blood pressure. The research question explored was what was the knowledge of hypertensive adults attending day clinics in Ga-Rankuwa regarding nutrition and hypertension management practices. An exploratory strategy was used as no similar research had previously been conducted in Ga-Rankuwa. A cross sectional survey design was used to investigate hypertensive adults attending the three primary health clinics in Ga-Rankuwa. The sampling method was convenient and the sample size 101 participants. Two data gathering methods were used, these being physical measurements and self-report. For the self-report, a structured interview was conducted. The data were analysed using descriptive statistics. The results indicated a lack of knowledge regarding nutrition and management of hypertension. The proportion of participants with uncontrolled hypertension was high (58.6%) and non-compliance with medication occurred frequently (58.1%). A third (28.7%) of the sample lacked knowledge of the complications of hypertension (28.7%). A community-based intervention, based on the results of the study, is recommended.

Autoinducer of virulence as a target for vaccine and therapy against Staphylococcus aureus.

Staphylococcus aureus causes pathologies ranging from minor skin infections to life-threatening diseases. Pathogenic effects are largely due to production of bacterial toxin, which is regulated by an RNA molecule, RNAIII. The S. aureus protein called RAP (RNAIII activating protein) activates RNAIII, and a peptide called RIP (RNAIII inhibiting peptide), produced by a nonpathogenic bacteria, inhibits RNAIII. Mice vaccinated with RAP or treated with purified or synthetic RIP were protected from S. aureus pathology. Thus, these two molecules may provide useful approaches for the prevention and treatment of diseases caused by S. aureus.

Palliative care: a positive outcome for cancer patients?

The development of palliative care in terms of recognizing the needs of the dying, palliative care becoming a nursing and medical speciality, the involvement of the World Health Organization in palliative care and the continuous development of treatment modalities available to cancer patients creates the expectation that the outcomes for the patient should also be positively influenced. The purpose of the study was to determine the most common symptoms of advanced cancer patients treated in a public and private hospital in Tshwane, and whether advances in palliative care improved the outcomes for these patients by decreasing the prevalence of symptoms experienced. The design of the study was a quantitative survey. The population consisted of patients with advanced cancer receiving palliative treatment as out patients in radiation and medical oncology clinics in a public and private hospital the Tshwane Metropolitan area. The sampling method was convenient and the sample size was 148 participants (n = 148). Data was gathered by means of an interview and self report. Data analysis was done by means of descriptive statistics. The results of the study indicated that a high number of patients still experience problems that could have been prevented. Pain was found to be the biggest problem for patients (76.4%) followed by weakness and fatigue (65.5%), nausea and vomiting (65.5%) and a dry mouth (46.6%). Thirst was reported by 41.2% of the sample. The study provides evidence that the development of palliative care did not have a positive outcome for patients by reducing the prevalence of symptoms experienced.

Health care practices influencing health promotion in urban black women in Tshwane.

Health promotion is a multifaceted activity. Women and children are particularly vulnerable regarding access to quality health care, with young African women reportedly the poorest and most economically marginalised and least educated sector in South Africa. Understanding the context within which a person lives is an essential component in the health educator's teaching strategy. Understanding urban black women's health care practices will enable health promoters to develop interventions that are successful. The problem investigated was to gain an understanding of the health care practices of urban black women that could influence health promotion activities. The design was qualitative exploratory. The respondents were women living in an urban township in Tshwane, South Africa. The sampling method was convenient and purposive and the sample size was determined by saturation of the data. Data was gathered through semi-structured interviews using six specific themes and the analysed using open coding. The results indicated that the social environment created by the registered nurses in the primary health influenced the health care practices of the women negatively. Practices regarding the seriousness of a health problem suggest a possible reason for late admission of a person with a serious health problem.

Lifestyle risk factors in an urban South African community.

The research question addressed in the study was to determine the prevalence of the following lifestyle risk factors: obesity, waist-hip ratio, physical inactivity, high blood glucose, and hypertension in an urban community. The research objective for the study was to determine the prevalence of specific risk factors in an urban community. Based on the results, a health intervention could be planned and implemented to reduce the prevalence of the risk factors and the possibility of chronic non-communicable diseases in later life. The design was a quantitative survey using physical measurement and a structured questionnaire. The target population of the study was black urban adults (n=218). The sampling method was convenient and purposive. The results of the study indicated that the prevalence of hypertension and obesity were higher than the national prevalence for South Africa. The waist-hip ratio revealed that 20% of the men and 49.7% of the women were at risk for cardiovascular disease. High blood glucose levels were demonstrated for 21.6% of the group. Physical activity was also shown to be inadequate. In conclusion, the potential for cardiovascular and metabolic health problems in future is high. It is recommended that an intervention, based on the results of the study, should and must be developed and implemented. The more challenging question is to know what to do and how to do it. A framework is suggested to guide the development of an intervention.

Integration of research and nursing experiential learning: a case study.

Teaching research to undergraduates has it own challenges and involving undergraduates in research practical experience is just one of those challenges. As nursing students are in the process of becoming professional nurses, knowledge and skills in research are specific outcomes of the curriculum. One of the outcomes of the B Tech Nursing Science programme offered by the Tshwane University of Technology states that for the baccalaureate nursing programme include analysis, interpretation and utilisation of a range of research findings in scientific nursing and midwifery care as well as the development of a research protocol in a given context. In an effort to ensure that students would experience research as an essential part of their daily activities, an integrated approach is suggested whereby the nursing experiential learning opportunities are also research experiential learning opportunities. Using the integration strategy, research theory come 'alive' for the students. The integration approach is uncomplicated and transferable to any other discipline. The case study presented is the second year nursing students using school nursing experiential learning as a research project. The second year nursing students have a community focus during their second year and one of the experiential learning opportunities is school health nursing in a primary school in Tshwane. The results of the school health survey are presented. The students developed a health education intervention based on the research results.

Risk factors for cardiovascular disease in the Ga-Rankuwa community.

Cardiovascular disease is the most common and yet one of the most preventable causes of death in the world. Rapid urbanization in South Africa is accompanied by rapid changes in lifestyle and environmental exposure that increase the burden of chronic cardiovascular diseases. Risk factors, modifiable or nonmodifiable, exist that increases a person's chances of developing cardiovascular disease. Though some knowledge is available about the prevalence of the risk factors in South Africa, no information is available regarding the community of Ga-Rankuwa. The purpose of the study was therefore to investigate the prevalence of risk factors for cardiovascular disease amongst the working-age people (18-40 years) in Ga-Rankuwa community. A quantitative survey was done and the sample was selected from zone 1, 2, 4, and 16 of Ga-Rankuwa from July 2005 to October 2005. The sampling method was census sampling (n=604). The data-gathering was self-report using a structured questionnaire as well as physical measurement. Data were analysed using descriptive statistics. The results indicated that risk factors, specifically obesity, physical inactivity and hypertension, were very prevalent in Ga-Rankuwa community. Different distributions of risk factors exist in the various sex and age groups. This finding again emphasises the importance of not developing health interventions with a single focus, for example hypertension or obesity. The risk factors are interwoven and affect each other. It is important to initiate a comprehensive health project to lower the risk factors of cardiovascular diease in the Ga-Rankuwa community.

Exploration of knowledge, attitudes and percepions regarding sexually transmitted infections among patients attending a primary health care clinic in Gauteng--part 1.

Sexually transmitted infections are a major public health problem in South Africa. The high incidence and prevalence of sexually transmitted infections in South Africa pose a serious threat to public health for two main reasons. Firstly, the long-term consequences of these infections are a major cause of loss of health or life, and secondly, sexually transmitted infections are important co-factors in driving the human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) epidemic. The control and prevention of sexually transmitted infections has become an urgent priority. At a primary health care clinic, the nursing personnel experienced an increasing number of persons daily seeking treatment for sexually transmitted infections. The purpose of the study was therefore to investigate the knowledge, attitudes and perceptions of people seeking treatment at Stanza Bopape Clinic regarding sexually transmitted infections. The study was a contextual, quantitative survey. The population was all patients (15 years and older) who visited the clinic for a health-related problem during November 2004 to January 2005. The sampling method was convenient. The data gathering method was self-report using a structured questionnaire basic on current knowledge. The data analysis was done with descriptive statistics.

Guidelines to reduce sexually transmitted infections at primary health care centres--part 2.

Sexually transmitted diseases are the second highest cause of death among women aged 15-44 years. The incidence and prevalence of sexually transmitted diseases is on the increase at many health care centres despite their dreadfulness and many preventative measures. According to the Scope of Practice of registered professional nurses working in a community health clinic, the registered professional nurse has a responsibility to prevent disease and promote health as well as do research. This paper aims to describe guidelines to reduce sexually transmitted infections at primary health care centres based on research done to investigate the community specific knowledge, attitudes and perceptions regarding sexually transmitted infections. Structured interviews were used to collect data from 1694 participants (males and females) who were consulted at a primary health care clinic in Mamelodi, Gauteng province. Existing patients' records were also utilised to calculate the incidence rate of sexually transmitted infections. Data were computerised and analysed quantitatively to reflect the results in frequencies and percentages as reported in Part 1 of this research. Guidelines to direct the practice of registered professional nurse were developed based on the findings of the results. These guidelines must underpin community specific interventions to reduce the incidence of sexually.

Bcl-2-mediated resistance to apoptosis is associated with glutathione-induced inhibition of AP24 activation of nuclear DNA fragmentation.

Studies on the mechanism of apoptosis in this laboratory support a model in which signal transduction involving caspase 3 leads to activation of a serine protease called Mr 24,000 apoptotic protease (AP24), which then induces internucleosomal DNA fragmentation in the nucleus. This study examined the effect of Bcl-2 overexpression on activation of AP24 and the induction of DNA fragmentation by AP24 in isolated nuclei. It was demonstrated that overexpression of Bcl-2 in either HL-60 or PW leukemia cell lines suppressed activation of AP24 induced by either tumor necrosis factor or UV light and protected cells from apoptosis. Furthermore, nuclei isolated from Bcl-2-overexpressing cells were relatively resistant to internucleosomal DNA fragmentation induced by AP24 isolated from apoptotic cells. Bcl-2-overexpressing cells that were nutritionally depleted of glutathione (GSH) became sensitive to tumor necrosis factor- or UV light-induced activation of AP24 and underwent apoptotic cell death. Moreover, nuclei isolated from Bcl-2-overexpressing cells that were depleted of GSH became sensitive to AP24-induced DNA fragmentation. The addition of exogenous GSH blocked the proteolytic activity of AP24, as well as its ability to induce DNA fragmentation in normal isolated nuclei. These results indicate that Bcl-2 can attenuate at least two events in the AP24 apoptotic pathway: activation of AP24 and induction of DNA fragmentation by activated AP24. Furthermore, agents that deplete intracellular levels of GSH may have therapeutic use in the sensitization of Bcl-2-overexpressing cancer cells to apoptotic cell death.

An internal ribosome entry segment in the 5' untranslated region of the mnt gene.

Mnt is a transcriptional repressor related to the Myc/Mad family of transcription factors. It is expressed in proliferating, resting and differentiating cells and is believed to antagonize the function of Myc. Here we have characterized the major transcription initiation site of the mnt gene. In doing so we noted a remarkable level of sequence conservation between the murine and human 5' untranslated regions. Our experiments revealed that this sequence contains an internal ribosome entry segment (IRES). In addition, we show that sequences at both the 5' and 3' end of the IRES are essential for its function. These findings indicate that mnt can be translated by internal initiation. Such a mechanism may allow efficient Mnt synthesis when cap-dependent translation initiation is reduced.

A conceptual framework for teaching research in nursing.

Though research is often referred to the lifeblood, hallmark or cornerstone in the development of a profession (Brink, 1996:2), teaching research in nursing is a challenge. The challenge does not just lie in teaching the subject, but in resistance and unwillingness of students to engage in the subject. In the experience of the researcher, registered nurses identify themselves with being a nurse and a caregiver; the role of researcher has never been internalised. The challenge is to achieve the outcome envisaged, namely, nurses who are knowledgeable consumers of research as well as continuous productive scholars in their application of nursing. Research generates knowledge and knowledge is the basis of caring with excellence. Nursing is an art and a science and the science must produce the knowledge upon which the art is based. The purpose of this article is to propose a conceptual framework of how to teach research in order to achieve such a successful outcome. The conceptual framework proposed in this article is based on four pillars, theoretical knowledge of research, scientific writing, psychological support and experiential learning. The importance of the research facilitator, not just as a teacher but also as a positive role model, is also described.