550 research outputs found
Approach to female urinary incontinence : Part 2 : Surgical management
Part one of this article deals with the assessment and medical
management of the disease. The following will delve into surgical
techniques in the armamentarium of treatment for both urge and
stress urinary incontinence.http://www.journals.co.za/content/journal/medogObstetrics and Gynaecolog
Approach to female urinary incontinence : Part 1 : Medical management
Urinary incontinence is defined as the involuntary loss of urine. It is a ubiquitous disorder, thought to occur more commonly than
more familiar health issues such as hypertension, diabetes, and
depression. It is a condition whose profile of affected patients
includes women of all age groups and which transcends socioeconomic
and cultural circumstance.2 Given the above, the social,
emotional, and economic impact of the disease on individuals and
communities is self-evident.
The true prevalence of urinary incontinence world-wide, and
in South Africa is essentially unknown. Community based studies
have reported the prevalence as ranging between 14% and 67%,
showing a large discrepancy from the estimates of physician-based
studies, which show an estimated prevalence of between 0.5-5%. This disparity is thought to arise from a combination of underreporting,
under-diagnosis, and under-treatment of the disease.http://www.journals.co.za/content/journal/medogam2019Obstetrics and Gynaecolog
Measles virus host invasion and pathogenesis
Measles virus is a highly contagious negative strand RNA virus that is transmitted via the respiratory route and causes systemic disease in previously unexposed humans and non-human primates. Measles is characterised by fever and skin rash and usually associated with cough, coryza and conjunctivitis. A hallmark of measles is the transient immune suppression, leading to increased susceptibility to opportunistic infections. At the same time, the disease is paradoxically associated with induction of a robust virus-specific immune response, resulting in lifelong immunity to measles. Identification of CD150 and nectin-4 as cellular receptors for measles virus has led to new perspectives on tropism and pathogenesis. In vivo studies in non-human primates have shown that the virus initially infects CD150+ lymphocytes and dendritic cells, both in circulation and in lymphoid tissues, followed by virus transmission to nectin-4 expressing epithelial cells. The abilities of the virus to cause systemic infection, to transmit to numerous new hosts via droplets or aerosols and to suppress the host immune response for several months or even years after infection make measles a remarkable disease. This review briefly highlights current topics in studies of measles virus host invasion and pathogenesis
Haematology and clinical chemistry values for harbour seals (Phoca vitulina) fed environmentally contaminated herring remain within normal ranges
Abstract: Twenty-two young harbour seals (Phoca vitulina) were fed herring from either the relatively unpolluted Atlantic Ocean or the heavily polluted Baltic Sea as part of a 2½-year immunotoxicological study. Blood samples taken at regular intervals were analyzed for routine haematology and clinical chemistry. Minimal differences between the two groups were observed in these parameters over the course of the experiment. Of the 20 clinical chemistry parameters analyzed, slight differences were found in serum levels of urea, creatinine, magnesium, and cholesterol. In haematology profiles, red blood cell counts and haematocrit values were higher in seals fed Baltic herring, but these differences diminished over time. Neutrophil counts were also higher in this group of seals, especially during the second half of the feeding study. Factors affecting haematological and clinical chemistry parameters within feeding groups included gender, age, and season. The data collected demonstrate a relative insensitivity of clinical chemistry parameters to the effects of chronic exposure to environmental contaminants accumulated through the food chain, but suggest the induction of clear alterations in differential white blood cel
The Informal Logic of Mathematical Proof
Informal logic is a method of argument analysis which is complementary to
that of formal logic, providing for the pragmatic treatment of features of
argumentation which cannot be reduced to logical form. The central claim of
this paper is that a more nuanced understanding of mathematical proof and
discovery may be achieved by paying attention to the aspects of mathematical
argumentation which can be captured by informal, rather than formal, logic. Two
accounts of argumentation are considered: the pioneering work of Stephen
Toulmin [The uses of argument, Cambridge University Press, 1958] and the more
recent studies of Douglas Walton, [e.g. The new dialectic: Conversational
contexts of argument, University of Toronto Press, 1998]. The focus of both of
these approaches has largely been restricted to natural language argumentation.
However, Walton's method in particular provides a fruitful analysis of
mathematical proof. He offers a contextual account of argumentational
strategies, distinguishing a variety of different types of dialogue in which
arguments may occur. This analysis represents many different fallacious or
otherwise illicit arguments as the deployment of strategies which are sometimes
admissible in contexts in which they are inadmissible. I argue that
mathematical proofs are deployed in a greater variety of types of dialogue than
has commonly been assumed. I proceed to show that many of the important
philosophical and pedagogical problems of mathematical proof arise from a
failure to make explicit the type of dialogue in which the proof is introduced.Comment: 14 pages, 1 figure, 3 tables. Forthcoming in Perspectives on
Mathematical Practices: Proceedings of the Brussels PMP2002 Conference
(Logic, Epistemology and the Unity of the Sciences Series), J. P. Van
Bendegem & B. Van Kerkhove, edd. (Dordrecht: Kluwer, 2004
Optimization and Dose Estimation of Aerosol Delivery to Non-Human Primates
Background: In pre-clinical animal studies, the uniformity of dosing across subjects and routes of administration is a crucial requirement. In preparation for a study in which aerosolized live-attenuated measles virus vaccine was administered to cynomolgus monkeys (Macaca fascicularis) by inhalation, we assessed the percentage of a nebulized dose inhaled under varying conditions. Methods: Drug delivery varies with breathing parameters. Therefore we determined macaque breathing patterns (tidal volume, breathing frequency, and inspiratory to expiratory (I:E) ratio) across a range of 3.3-6.5 kg body weight, using a pediatric pneumotachometer interfaced either with an endotracheal tube or a facemask. Subsequently, these breathing patterns were reproduced using a breathing simulator attached to a filter to collect the inhaled dose. Albuterol was nebulized using a vibrating mesh nebulizer and the percentage inhaled dose was determined by extraction of drug from the filter and subsequent quantification. Results: Tidal volumes ranged from 24 to 46 mL, breathing frequencies from 19 to 31 breaths per minute and I:E ratios from 0.7 to 1.6. A small pediatric resuscitation mask was identified as the best fitting interface between animal and pneumotachometer. The average efficiency of inhaled dose delivery was 32.1% (standard deviation 7.5, range 24%-48%), with variation in tidal volumes as the most important determinant. Conclusions: Studies in non-human primates aimed at comparing aerosol delivery with other routes of administration should take both the inter-subject variation and relatively low efficiency of delivery to these low body weight mammals into account
Morbillivirus infections: An introduction
Research on morbillivirus infections has led to exciting developments in recent years. Global measles vaccination coverage has increased, resulting in a significant reduction in measles mortality. In 2011 rinderpest virus was declared globally eradicated – only the second virus to be eradicated by targeted vaccination. Identification of new cellular receptors and implementation of recombinant viruses expressing fluorescent proteins in a range of model systems have provided fundamental new insights into the pathogenesis of morbilliviruses, and their interactions with the host immune system. Nevertheless, both new and well-studied morbilliviruses are associated with significant disease in wildlife and domestic animals. This illustrates the need for robust surveillance and a strategic focus on barriers that restrict cross-species transmission. Recent and ongoing measles outbreaks also demonstrate that maintenance of high vaccination coverage for these highly infectious agents is critical. This introduction briefly summarizes the most important current research topics in this field
Optimization and Dose Estimation of Aerosol Delivery to Non-Human Primates
Background: In pre-clinical animal studies, the uniformity of dosing across subjects and routes of administration is a crucial requirement. In preparation for a study in which aerosolized live-attenuated measles virus vaccine was administered to cynomolgus monkeys (Macaca fascicularis) by inhalation, we assessed the percentage of a nebulized dose inhaled under varying conditions.
Methods: Drug delivery varies with breathing parameters. Therefore we determined macaque breathing patterns (tidal volume, breathing frequency, and inspiratory to expiratory (I:E) ratio) across a range of 3.3-6.5 kg body weight, using a pediatric pneumotachometer interfaced either with an endotracheal tube or a facemask. Subsequently, these breathing patterns were reproduced using a breathing simulator attached to a filter to collect the inhaled dose. Albuterol was nebulized using a vibrating mesh nebulizer and the percentage inhaled dose was determined by extraction of drug from the filter and subsequent quantification.
Results: Tidal volumes ranged from 24 to 46 mL, breathing frequencies from 19 to 31 breaths per minute and I: E ratios from 0.7 to 1.6. A small pediatric resuscitation mask was identified as the best fitting interface between animal and pneumotachometer. The average efficiency of inhaled dose delivery was 32.1% (standard deviation 7.5, range 24%-48%), with variation in tidal volumes as the most important determinant.
Conclusions: Studies in non-human primates aimed at comparing aerosol delivery with other routes of administration should take both the inter-subject variation and relatively low efficiency of delivery to these low body weight mammals into account
Estrogen causes ultrastructural changes of fibrin networks during the menstrual cycle : a qualitative investigation
INTRODUCTION : Hormonal fluctuations may influence fibrin structure. During the
menstrual cycle, plasma fibrinogen levels change, mainly due to the variations of estrogen.
Throughout the menstrual cycle estrogen levels peak twice, first during the mid-follicular phase
and then a lower second peak during the luteal phase. MATERIALS AND METHODS : In order to investigate
the possible changes in the fibrin network throughout the menstrual cycle, the fibrin network
ultrastructure of six healthy female participants were studied at different intervals in the
menstrual cycle where differences in estrogen levels are prevalent. Blood plasma smears were
prepared for scanning and transmission electron microscopy analysis. RESULTS : The external and
internal structure of the fibrin fibers showed different morphologies throughout the menstrual
cycle. The fibrin fibers were smooth during days 1–5. However, during days 12–14 of the menstrual
cycle the fibrin fiber morphology started to change, becoming less smooth. During the
luteal phase of the cycle (days 20–25), the network appears sticky, where the minor, thin fibers
are more prominent between the thick fibers when compared to the menstrual phase. CONCLUSION :
The two estrogen peaks of the menstrual cycle coincide with the changes seen in the current
qualitative research, where the fibrin morphology changes during the same time as the
estrogen peaks occur. Purified fibrinogen confirmed that it is indeed estrogen that causes the
altered fibrin network morphology. This research is the first to show ultrastructural changes in
fibrin fiber morphology resulting from estrogen changes during the menstrual cycle.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1097-00292015-08-31hb201
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