921 research outputs found
Focus on plasma medicine
‘Plasma Healthcare’ is an emerging interdisciplinary research topic
of rapidly growing importance, exploring considerable opportunities at the
interface of plasma physics, chemistry and engineering with life sciences. Some
of the scientific discoveries reported so far have already demonstrated clear
benefits for healthcare in areas of medicine, food safety, environmental hygiene,
and cosmetics. Examples include ongoing studies of prion inactivation, chronic
wound treatment and plasma-mediated cancer therapy. Current research ranges
from basic physical processes, plasma chemical design, to the interaction of
plasmas with (i) eukaryotic (mammalian) cells; (ii) prokaryotic (bacteria) cells,
viruses, spores and fungi; (iii) DNA, lipids, proteins and cell membranes; and
(iv) living human, animal and plant tissues in the presence of biofluids. Of
diverse interests in this new field is the need for hospital disinfection, in particular
with respect to the alarming increase in bacterial resistance to antibiotics, the
concomitant needs in private practices, nursing homes etc, the applications in
personal hygiene—and the enticing possibility to ‘design’ plasmas as possible
pharmaceutical products, employing ionic as well as molecular agents for
medical treatment. The ‘delivery’ of the reactive plasma agents occurs at the
gaseous level, which means that there is no need for a carrier medium and access
to the treatment surface is optimal. This focus issue provides a close look at the
current state of the art in Plasma Medicine with a number of forefront research
articles as well as an introductory review
Counting the cost of preventable diabetes-related lower limb amputations at a single district hospital in KwaZulu-Natal: what does this mean, what can be done?
Background: Healthcare policy decisions are driven by many factors, including cost, hence the need to show costs of diabetes mellitus-related lower limb amputations (DMLLA) to inform amendments to health care. Substantial decreases in amputation rates are associated with specialised podiatry foot clinics and ongoing foot education, as per national guidelines on the multidisciplinary team approach (MDTA) to diabetes health care. There are only two podiatry posts in KwaZulu-Natal (KZN) state health department (DoH).Objectives: Aims were to draft the medical costs for 660 DMLLA at Greys Hospital for the period 2013–2017; to extrapolate costs on annual DMLLA in KZN; to outline socio-economic costs for future investigation; to present evidence that podiatry in the MDTA can decrease numbers of DMLLA.Methods: A retrospective review on clinical data captured in real time and maintained by the Pietermaritzburg Metropolitan Trauma Service (PMTS) and Surgical Service (PMSS) was performed. Costs were analysed on data for 660 patients’ DMLLA at Greys Hospital between 2013 and 2017, and psychological and socio-economic costs via literature review.Results: Medical care at Greys Hospital for 660 DMLLA in the five years cost in excess of ZAR 213 million. Extrapolated to the 1 231 diabetic amputations (2014) equals an annual cost to KZN DoH in excess of ZAR 398 million. Personal, family loss and socio-economic costs are estimated in excess of ZAR five million per amputee, resulting in further cost of ZAR 6.155 billion per annum to KZN. Extrapolation across 11 provinces signifies a national cost of at least ZAR 68 billion.Conclusions: We present a gauge of the cost of DMLLA to KZN and national health. Substantial possible socio-economic losses compound these. The role of podiatrists within MDTA teams has an evidence base to prevent DMLLA
Open-closed field algebras
We introduce the notions of open-closed field algebra and open-closed field
algebra over a vertex operator algebra V. In the case that V satisfies certain
finiteness and reductivity conditions, we show that an open-closed field
algebra over V canonically gives an algebra over a \C-extension of the
Swiss-cheese partial operad. We also give a tensor categorical formulation and
categorical constructions of open-closed field algebras over V.Comment: 55 pages, largely revised, an old subsection is deleted, a few
references are adde
The spectrum and outcome of paediatric traumatic brain injury in KwaZulu-Natal Province, South Africa has not changed over the last two decades
Objectives. This retrospective review of a prospectively entered and maintained hybrid electronic trauma registry was intended to develop a comprehensive overview of traumatic brain injury (TBI) in children and adolescents and to compare it with previous audits from our local environment and from other developing world centres. All TBI patients admitted to hospital were included in this study. We reviewed the age, gender, outcomes, radiological findings and treatment of the patients.Methods. All patients aged ≤18 years old who were admitted by the Pietermaritzburg Metropolitan Trauma Service (PMTS) with TBI between December 2012 and December 2016 were included in this audit.Results. During the 4-year period under review, a total of 563 children and adolescents were treated for TBI by the PMTS. The median age was 6.4 years and 29% (n=165) were females. The mechanism of TBI was blunt trauma in 96% (n=544) of cases, with 4% (n=19) suffering penetrating trauma. The penetrating mechanisms included impalement by a cow horn and miscellaneous injuries due to saws, axes, barbed wire, spades, stones and knives. The blunt mechanisms included falls (n=102), assaults (n=108), collapse of a building (n=28), bicyclerelated injury (n=14), falling off a moving vehicle (n=280), motor vehicle accident (MVA; n=59), pedestrian vehicle accident (PVA; n=183) and animal-related injuries (n=8). There were 454 (80%) mild, 67 (12%) moderate and 42 (7%) severe cases of TBI. A total of 48 patients were admitted to the intensive care unit and 23 were admitted to the high care unit. Nine patients died. All the deaths were in the MVA and PVA group. The spectrum of TBI as diagnosed on computed tomography scans was nonspecific cerebral contusion (n=92), depressed skull fracture (n=70), sub-arachnoid haemorrhage (n=60), extradural haemorrhage (n=41), intracerebral haemorrhage (n=19), free air (n=19),subdural haemorrhage (n=13), intraventricular haemorrhage (n=9). A total of 62 (11%) patients required surgery.Conclusion. There is a significant burden of paediatric TBI in Pietermaritzburg. The majority of TBI was related to blunt trauma and assaults were very common. Although the short-term outcomes are good, the long-term consequences are poorly understood. Injury prevention programmes are needed to help reduce this burden of disease and a nationwide trauma registry is long overdue
Efficacy of spinal cord stimulation as adjuvant therapy for intractable angina pectoris: A prospective, randomized clinical study
AbstractObjective. In a prospective, randomized study with an 8-week follow-up period, we evaluated the efficacy of spinal cord stimulation on exercise capacity and quality of life in patients with intractable angina.Background. Despite important achievements in therapy for ischemic heart disease, there remain patients with intractable symptoms of angina. In uncontrolled observations, several investigators have reported beneficial effects of spinal cord stimulation as an additional therapy for patients with angina pectoris.Methods. Seventeen patients were randomly assigned to the treatment (implantation within 2 weeks, eight patients) or control (implantation after 8 weeks, nine patients) group. Assessment of exercise capacity was performed by treadmill exercise testing. Quality of life was evaluated by daily and social activity scores and recording sublingual glyceryl trinitrate intake and angina pectoris attacks in a diary. After the 8-week study period, the control group also received the spinal cord stimulation device, and all patients were followed up for 12 months.Results. The treatment but not the control group demonstrated a significant increase in exercise duration (p < 0.02), rate-pressure product (p < 0.03) and time to angina (p < 0.04), with a decrease in ST segment depression (p < 0.05). This was associated with an increase in daily life (p < 0.008) and social activity (p < 0.005) scores and a reduction in glyceryl trinitrate intake (p < 0.004) and episodes of angina pectoris (p < 0.003). During the 1-year follow-up, improvement in an quality of life variables was linear for the entire group compared with baseline. The time to angina, exercise duration and ST segment depression showed a second-order trend.Conclusions. Spinal cord stimulation significantly improves exercise capacity and quality of life. On the basis of an increase in exercise capacity and rate-pressure product, the mechanism by which spinal cord stimulation acts may be related to improved oxygen supply to the heart combined with an analgesic effect
Validation of the Simplified Motor Score in patients with traumatic brain injury at a major trauma centre in South Africa
Background. This study used data from a large prospectively entered database to assess the efficacy of the motor score (M score) component of the Glasgow Coma Scale (GCS) and the Simplified Motor Score (SMS) in predicting overall outcome in patients with traumatic brain injury (TBI).Objective. To safely and reliably simplify the scoring system used to assess level of consciousness of trauma patients in the acute setting.Methods. A retrospective observational review of the Pietermaritzburg Metropolitan Trauma Service hybrid electronic medical registry database was performed during the period January 2013 - December 2015. Patients were classified into three groups using their GCS as an injury severity score. These were mild TBI (GCS 13 - 15), moderate TBI (GCS 9 - 12) and severe TBI (GCS <9). The Glasgow M score was specifically evaluated to determine the relationship between the individual motor component and patient outcome.Results. GCS scores and M scores were analysed in a total of 830 patients. There was a decline in survival rate when the M score on admission was ≤4. The decline was more significant when the M score was ≤3. Survival rates were 26.8% (11/41) for patients with an M score of 1, 63.6% (14/22) for those with a score of 2, 56.5% (13/23) for those with a score of 3, 80.0% (20/25) for those with a score of 4, and 95.5% (121/128) for those with a score of 5. Of 591 patients with an M score of 6, 580 (98.1%) survived. Mortality rose dramatically with declining SMS. This was highly significant. When the M score was plotted against mortality in 830 patients, there was a correct prediction in 769 cases (accuracy 92.7%, sensitivity 67.6%, specificity 95%). The area under the receiver operating characteristic (ROC) curve was 0.9037, with a standard deviation (area) of 0.0227. When comparing the SMS against mortality, the accuracy was 77.1%, the sensitivity 84.5% and the specificity 76.4%. The fitted ROC area was 0.891 and the empirical ROC area 0.86.Conclusion. The M score component of the GCS and the SMS accurately predict outcome in patients with TBI. In cases where the full GCS is difficult to assess, the M score and SMS can be used safely as a triage tool
Trauma electives in South Africa provide valuable training for international surgeons
Background. Trauma electives in South Africa (SA) are common and many foreign-based surgeons have undertaken such electives over the past 3 decades. Despite this, little academic attention has been paid to these electives, which remain largely informal and unstructured. This project aims to redress this deficit.Objectives. To investigate and document the extent of trauma clinical electives and to assess their impact on the careers of foreign surgeons who have undertaken such electives.Methods. A mixed methods-style questionnaire was compiled, which sought to document the demographics of surgeons undertaking an SA trauma clinical elective, the trauma clinical experience they had prior to the elective, as well as the volume of experience they acquired during the elective.Results. Sixty questionnaires were sent out and 21 were completed. There were 16 male and 5 female respondents. Only 17 had undertaken a formal trauma rotation before their elective in SA. The mean number of major resuscitations managed prior to rotating through surgery departments in SA was 15, and the mean number managed during a 12-month rotation in SA was 204. It would take each respondent 14 years in their country of origin to acquire an equivalent level of exposure to major resuscitation. During the year before their elective, each surgeon had been exposed to a mean number of the following: 0.5 gunshot wounds (GSWs), 2 stab wounds (SWs), 0.1 blast injuries and 19 road traffic accidents (RTAs). The equivalent mean number for their year in SA was 106 GSWs, 153 SWs, 4 blast injuries and 123 RTAs. The time necessary to achieve a similar level of exposure to their SA experience if they had remained in their country of origin was 213 years for GSWs, 73 years for SWs, 41 years for blast injuries and 7 years for RTAs. Compared with their SA elective, it would take each respondent 3 years to insert as many central venous lines, 9 years to perform the same number of tube thoracostomies, 9 years to manage as many surgical airways, 18 years to explore as many SWs of the neck and 93 years to explore as many GSWs of the neck. Furthermore, it would take 33 years to see and perform as many laparotomies for SWs to the abdomen, 374 years to perform an equivalent number of GSWs to the abdomen and 34 years of experience to perform as many damage-control laparotomies in their countries of origin. In terms of vascular trauma, it would take 23 years to see as many vascular injuries secondary to SWs and 77 years to see an equivalent number of vascular injuries secondary to GSWs.Conclusions. A trauma clinical elective in SA provides an unparalleled exposure to almost all forms of trauma in conjunction with a welldeveloped academic support programme. Formalising these trauma electives might allow for the development of exchange programmes for SA trainees who wish to acquire international exposure to advanced general surgical training
Defining the need for surgical intervention following a snakebite still relies heavily on clinical assessment: The experience in Pietermaritzburg, South Africa
Background. This audit of snakebites was undertaken to document our experience with snakebite in the western part of KwaZulu-Natal (KZN) Province, South Africa (SA).Objective. To document our experience with snakebite in the western part of KZN, and to interrogate the data on patients who required some form of surgical intervention.Methods. A retrospective study was undertaken at the Pietermaritzburg Metropolitan Trauma Service, Pietermaritzburg, SA. The Hybrid Electronic Medical Registry was reviewed for the 5-year period January 2012 - December 2016. All patients admitted to the service for management of snakebite were included.Results. The offending snake is rarely identified, and the syndromic approach is now the mainstay of management. Most envenomations seen during the study period were cytotoxic, presenting with painful progressive swelling (PPS). We did not see any purely neurotoxic or haemotoxic envenomations. Antivenom is required for a subset of patients. The indications are essentially PPS that increases by >15 cm over an hour, PPS up to the elbow or knee after 4 hours, PPS of the whole limb after 8 hours, threatened airway, shortness of breath, associated clotting abnormalities and compartment syndrome. If no symptoms have manifested within 1 hour of a snakebite, clinically significant envenomation is unlikely to have occurred. Antivenom is associated with a high rate of anaphylaxis and should only be administered when absolutely indicated, preferably in a high-care setting under continuous monitoring. The need for surgery is less well defined. Urgent surgery is indicated for compartment syndrome of the limb, which is a potentially life- and limb-threatening condition. Its diagnosis is usually made clinically, but this is difficult in snakebites. Morbidity and cost increase dramatically once fasciotomy is required, as evidenced by much longer hospital stay. There is frequently a degree of cross-over between cytotoxicity and haemotoxicity in envenomations that require fasciotomy, which means that fasciotomy may result in catastrophic bleeding and should be preceded by the administration of antivenom, especially in patients with a low platelet count or a high international normalised ratio. Physiological and biochemical markers are unhelpful in assessing the need for fasciotomy. Objective methods include measurement of compartment pressures and ultrasound.Conclusion. The syndromic management of snakebite is effective and safe. There is a high incidence of anaphylactic reactions to antivenom, and its administration must be closely supervised. In our area we overwhelmingly see cytotoxic snakebites with PPS. Surgery is often needed, and we need to refine our algorithms in terms of deciding on surgery
Smoking-gun signatures of little Higgs models
Little Higgs models predict new gauge bosons, fermions and scalars at the TeV
scale that stabilize the Higgs mass against quadratically divergent one-loop
radiative corrections. We categorize the many little Higgs models into two
classes based on the structure of the extended electroweak gauge group and
examine the experimental signatures that identify the little Higgs mechanism in
addition to those that identify the particular little Higgs model. We find that
by examining the properties of the new heavy fermion(s) at the LHC, one can
distinguish the structure of the top quark mass generation mechanism and test
the little Higgs mechanism in the top sector. Similarly, by studying the
couplings of the new gauge bosons to the light Higgs boson and to the Standard
Model fermions, one can confirm the little Higgs mechanism and determine the
structure of the extended electroweak gauge group.Comment: 59 pages, 10 figures. v2: refs added, typos fixed, JHEP versio
A Little Higgs model of neutrino masses
Little Higgs models are formulated as effective theories with a cut-off of up
to 100 times the electroweak scale. Neutrino masses are then a puzzle, since
the usual see-saw mechanism involves a much higher scale that would introduce
quadratic corrections to the Higgs mass parameter. We propose a model that can
naturally accommodate the observed neutrino masses and mixings in Little Higgs
scenarios. Our framework does not involve any large scale or suppressed Yukawa
couplings, and it implies the presence of three extra (Dirac) neutrinos at the
TeV scale. The masses of the light neutrinos are induced radiatively, they are
proportional to small (\approx keV) mass parameters that break lepton number
and are suppressed by the Little Higgs cut-off.Comment: 10 pages, 3 figure
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