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The diagnostic value of pericardial aspiration at Groote Schuur hospitalJennison, S H January 1990 (has links)
In this MMed thesis I have reviewed retrospectively the pericardial aspirations performed between 1 July 1987 and 12th October 1989 at Groote Schuur Hospital, Cape Town. Documenting the reasons for aspiration, the complications of pericardiocentesis, and how cytologic, bacteriologic and biochemical examination of the aspirate influenced the clinicians' management of the 52 patients reviewed. The relatively low mortality of less than 2% is noted, in a procedure carried out for the relief of cardiac tamponade in 57% of the patients. A significant relationship between an ADA level higher than 51 international units per litre and a positive culture of mycobacterium tuberculosis from pericardial aspiration is demonstrated. The relatively low successful culture of mycobacterium tuberculosis (32% of the 29 patients clinically assessed as having tuberculous pericarditis) is noted, and recommendations to improve the yield from culture are made.
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Neurovascular lesions and mechanisms in suicidal hanging: an anatomical, physiological and pathological studyMoar, Jacob Joseph 25 April 2013 (has links)
Thesis (Ph.D.)--University of the Witwatersrand, Faculty of Health Sciences, 2012 / Background and Purposes
Suicide by hanging is a relatively common occurrence. The actual cause of death in
suicidal hanging is, however, controversial, having been attributed variously to
asphyxia, carotid artery compression and vagal nerve stimulation.
The aim of this Ph.D thesis was to determine the possible neurovascular
cause of death in suicides by hanging by careful study of the anatomy and
physiology of the neck region in relation to the ensuing pathology. The study was,
therefore, approached from an anatomical, physiological, histological and
pathological pespective. It therefore comprised a detailed exploration of the anatomy
and physiology of the neck structures to match these with the underlying traumatised
neurovascular structures, the latter trauma being brought about by the suicidal
hanging process.
Methods
The methods used in the study included an investigation of the ligature and position
of the ligature in relation to the level of the neck and the physical effects of the
ligature on the skin and underlying anatomical structures. A careful and detailed
dissection of the neck was undertaken and samples of the vessels and nerves were
processed for histological study. Fifty consecutive cases of suicidal hanging and five
“non-hanging” cases which served as controls were used in the study. In addition, ten
cases of suicidal hanging not included in the study were subjected to occlusion
studies by means of probe exploration. This technique and procedure was not carried
out or applied to the cases included in the study for fear that the probe itself might
produce artefactual damage to the delicate endothelium lining the inner layer of the
vessel wall.
The study was classified into various components such as:
1. Examination of the type and structure of the ligature material;
2. The position of the ligature on the neck, i.e. whether involving upper, middle,
or lower third of neck and to correlate this position with the underlying
anatomical structures subjected to the accompanying tensile, compressive and
haemodynamic forces;
3. The physical effects of the ligature upon the skin and the underlying deeper
neurovascular structures of the neck;
4. Meticulous “bloodless” dissection of the neck structures to corroborate any
pathology noted with the above three criteria. Currently, all putative causes of
death remain speculative;
5. Particular attention was paid to those structures most vulnerable to the
compressive forces, tensile forces and haemodynamic forces operative in
hanging. These comprise the neurovascular structures contained within the
fibrous carotid sheath and the phrenic nerves in the neck, in particular with
regard to the anatomical relationship of these structures to the positioning of
the ligature. As far as analysing the forces involved, the engineering
principles pertaining to these were interpreted in consultation with the
Faculty of Engineering at the University of the Witwatersrand. Results
The main findings of the study showed damage to vascular, neural (including
phrenic nerve), carotid bodies and accessory glomal bodies. The vascular
findings emerged following an examination of the total number of arteries in the
study, namely, 300, the figure derived as follows: six arteries in each of the fifty
hanging subjects, viz., the left common carotid artery, the right common
carotid artery, the left internal carotid artery, the right internal carotid
artery, the left external carotid artery and the right external carotid artery (6
x 50 = 300). The damage shown was particularly the case with regard to the
finding of tears in the various layers of the vessel wall. These extended from the
intima through to the adventitia or outermost layer of the vessel wall and these
were further subdivided into being either single or multiple.
The tears found ranged from those involving the intima alone (single tears
being found in 17 (5.6%) of the 300 arteries examined and multiple tears in 37
(12.3%) of the 300 arteries examined., the intima extending to the internal
elastic lamina (single tears being found in 20 (6.6%) of the 300 arteries
examined and multiple tears in 8 (2.6%) of the 300 arteries examined), tears
involving the intima and extending through to involve the media, i.e. intimomedial
tears and whether these latter tears involved the inner-, middle-, or
outer-thirds of the media (single or multiple). Single intimo-medial tears
extending through the intima to involve the inner-third of the media comprised
6 (2.0%) of the arteries examined, those extending from the intima to involve the
middle-third of the media comprised 3 (1.0%) of the 300 arteries examined and
single intimo-medial tears extending through the intima to involve the outeriv
third of the media similarly comprised 3 (1%) of the arteries examined. Multiple
intimo-medial tears extending through from intima to inner-, middle-, and outerthirds
of the media respectively, comprised 3 (1.0%), 5 (1.6%) and 1 (0.3%) of
the arteries examined.
Single tears involving the inner-third of the media alone comrised 6
(2.0%) of the 300 arteries examined, single tears involving the middle-third of
the media comprised 9 (3.0%) of the arteries examined and single tears
involving the outer-third of the media alone comprised 8 (2.6%) of the arteries
examined. Multiple tears involving the inner-, middle and outer-thirds of the
media respectively comprised 6 (2.0%), 13 (4.3%) and 16 (5.3%) of the arteries
examined.
Single tears involving both adventitia and media, i.e. adventitio-medial
tears extending through the inner-, middle-, or outer-thirds of the media to
involve the adventitia comprised 1 (0.3%), 2 (0.6%) and 6 (2.0%) respectively
of the 300 arteries examined. Multiple adventitio-medial tears of the inner-,
middle-, and outer-thirds of the media, respectively, comprised 0 (0.0%), 3
(1.0%) and 2 (0.6%) of the 300 arteries examined.
Single tears of the adventitia alone comprised 21 (7.0%) of the arteries
examined while multiple tears comprised 7 (2.3%). Complete circumferential
transverse rupture of the vessel wall was found in 3 (1.0%) of the arteries
examined while adventitial haemorrhage was found in 103 (34.3%) of the 300
arteries examined.
The vascular findings were represented numerically in tabular form in the 50
hanging subjects in Table III and were further analysed and compared with
regard to either unilateral or bilateral vessel involvement in the fifty (50) suicidal
hanging subjects and the findings represented in Tables IIIa (unilateral
involvement) and IIIb (bilateral involvement).
Additional vascular findings comprised endothelial elevation/avulsion,
internal elastic lamina dehiscence, subendothelial clefts, multiple medial
fenestrations, adventitio-medial separation, vascular congestion and a
vascular plane of cleavage. These were similarly represented in Table IV and
analysed with regard to unilateral or bilateral involvement in Tables IVa and IVb.
Endothelial elevation/avulsion was found in 295 (98.3%) of the 300 arteries
examined, internal elastic lamina dehiscence in 290 (96.6%) of the arteries
examined, subendothelial clefts in 289 (96.3%) of the arteries examined,
multiple medial fenestrations in 17 (5.6%) of the arteries examined, adventitiomedial
separation in 273 (91.0%) of the arteries examined, vascular congestion
in 224 (74.6%) of the arteries examined and a vascular plane of cleavage in 98
(32.6%) of the arteries examined. These findings, unexpected, showed the
extreme fragility and vulnerability of the intima and adventitia to the
compressive and tensile forces acting on the vessel wall during hanging, being
explicable not only on the basis of the various complex forces interacting
simultaneously during hanging but on the magnitude of forces applied. A
mathematical analysis, found at the end of the Discussion chapter, conducted in
order to estimate the minimum peak pressure applied and exerted on the vessel
wall during hanging, in collaboration with the School of Mechanical, Industrial
and Aeronautical Engineering at the University of the Witwatersrand, confirmed
the magnitude of these forces.
The neural findings (Table V) were divided into neural congestion, neural
haemorrhage, neural internal dehiscence, neural tearing and perineural
separation and these were similarly analysed with regard to either unilateral or
bilateral involvement in the fifty hanging subjects (Tables Va and Vb). Neural
congestion was found in association with 20 (6.6%) of the 300 arteries
examined, neural haemorrhage in14 (4.6%), neural internal dehiscence in 54
(18.0%), neural tearing in 35 (11.6%) and perineural separation in 112
(37.3%). Neural ganglionic findings were similarly divided into ganglionic
congestion, ganglionic haemorrhage, ganglionic internal dehiscence and
ganglionic tearing. Ganglionic congestion, in association with the 300 arteries
examined, was found in 20 (6.6%), ganglionic haemorrhage in 8 (2.6%),
ganglionic internal dehiscence in 15 (5.0%) and ganglionic tearing in 6
(2.0%).
The findings in the carotid bodies were divided into carotid body
congestion, carotid body haemorrhage, carotid body internal dehiscence and
carotid body tearing. Carotid body congestion, in association with the 300
arteries examined, was found in 8 (2.6%), carotid body haemorrhage in 2
(0.6%), carotid body internal dehiscence in 4 (1.3%) and carotid body tearing
in 2 (0.6%).
Accessory glomal body findings were, once again, divided into accessory
glomal congestion, accessory glomal haemorrhage, accessory glomal internal
dehiscence and accessory glomal tearing. However, in view of the close
anatomical association between the accessory glomal bodies and the adventitia
of the arterial walls, an additional pathological finding of accessory glomal
adventitial separation emerged. Accessory glomal congestion, in association
with the 300 arteries examined, was found in 20 (6.6%), accessory glomal
haemorrhage in 7 (2.3%), accessory glomal internal dehiscence in 50 (16.6%),
accessory glomal tearing in 18 (6.0%) and accessory glomal adventitial
separation in 124 (41.3%). This latter finding once again demonstrated the
vulnerability of the adventitial layer of the vessel wall to tensile forces,
separating it from its associated structures.
Damage to the phrenic nerves and surrounding muscles, underlying the site
of ligature application, was similarly found, suggesting a role for phrenic nerve
stimulation with consequent diaphragmatic paralysis in contributing to death in
the hanging process.
Discussion and Conclusion
In this Ph.D thesis the principles of dimensional analysis i.e., the breaking down
of a complex phenomenon into its component parts, have been applied. However,
in view of the complexity and proximity of structures to one another in the neck,
consisting not only of the rigid hyoid-larynx complex and vertebral column but
also the integrated vascular and neural structures, it appears that not one single
biological mechanism can be ascribed and attributed to the cause of death in
suicidal hanging. Rather, it appears that unconsciousness and death causation
appears to be multifactorial. Both the sympathetic and parasympathetic arms of
the autonomic nervous system are involved, often with antagonistic and therefore
paradoxical effects. In a ddition, pressure to the phrenic nerve, not previously
considered in playing a role in death causation in hanging, may, it is suggested,
be a major contributory factor in death causation. This nerve, the innervation to
the major muscle of respiration, i.e. the diaphragm, in a neural response to the
compressive and tensile forces in hanging, fixes the diaphragm in a state of
inspiratory paralysis. This latter effect would be further augmented by neural
stimulation of the accessory muscles of respiration, i.e. the sternocleidomastoid
and scaleni muscles, similarly lying deep to the site of ligature application,
contributing to the thoracic cage becoming fixed in a state of inspiratory
paralysis. This latter effect, as described in that section of the Discussion chapter
dealing with an analysis of the physiological functions at play, is brought about
by initiation of the dynamic and static stretch reflexes occurring in these
muscles on application of a compressive or tensile stimulus.
Compression of the carotid arteries, on the other hand, results, as shown, not
only in major damage to these vessels and their accompanying veins, but, in
addition, must produce a dramatic element of cerebral ischaemia with ensuing
loss of consciousness. It thus appears that loss of consciousness is the critical
factor for it is the state when the victim is no longer able to save himself or
herself. Without loss of consciousness survival may occur, but with it, death
becomes inevitable.
The question then arises :- what is the cause of unconsciousness? In
physiological terms, carotid artery occlusion induces rapid unconsciousness, i.e.
within 11 to 12 seconds, resulting ultimately in death. In other words, the sudden
application and unremitting pressure of the ligature must inevitably result in
death. On the other hand, the sudden application of a ligature with consequent
vagal nerve compression may produce instantaneous cardiac arrest with cessation
of blood flow to the brain and resultant loss of consciousness. This event would
produce unconsciousness in less than the time period of 11 seconds of carotid
artery occlusion (although the brain continues to survive for several minutes
thereafter despite cessation of heart beat). If, however, unconsciousness is
contributed to by phrenic nerve compression, it would not be instantaneous as
shown by the fact that one can normally hold one’s breath for several minutes (as
underwater swimmers do) and unconsciousness does not supervene either
instantaneously or within 11 seconds. In short, unconsciousness would not occur
within 11 seconds in the case of compression of the phrenic nerve unless a more
critical factor supervenes.Thus, the rapidity of onset of unconsciousness appears
to be the critical factor in determining the progression to ultimate (and inevitable)
death. Moreover, as pointed out in the Materials and Methods chapter, the
carotid arteries in several tested cases would not allow the passage of a probe
through the obstructed arteries beneath a tightly applied ligature. This obstruction
would, therefore, appear to be the initiator of the deadly unconsciousness factor,
although respiratory arrest would be compounded by neural and muscular
factors.
While in this thesis the principles of dimensional analysis i.e., the breaking
down of a complex phenomenon into its component parts have been applied, the
principles of integrated analysis i.e., the combining and synthesis of separate
parts into a whole have also been attempted. In essence, while it is suggested that
the neural elements play a pivotal role in the hanging process due to the neural
effect on both brain and heart as a result of autonomic nervous system
stimulation and the function of the phrenic nerve in respiration, it appears that
multiple factors, acting in concert, simultaneously or in rapid sequence to one
another, all play a role in contributing to death causation in the hanging process.
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Normal mandibular morphology of inbred mouse strainsEdwards, Michelle Halum January 2004 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Even though the molecular events and pathways that underlie craniofacial
development and morphogenesis are not fully understood, it is accepted that their
orchestration is influenced by the interaction of genetic and environmental factors.
Inbred mouse strains represent genetically homogenous groups of individuals. It is
established that mice in one strain often differ quite remarkably from mice in other inbred
strains. Those phenotypic differences make mice exceptional tools for the dissection of
genetic factors that influence normal and abnormal craniofacial morphogenesis. While
numerous investigations have focused on abnormal morphogenesis, a comprehensive
study of normal craniometric morphology across multiple inbred strains of mice has not
been previously performed. The Mouse Phenome Project, an international collaboration
of investigators, was formed to systematically phenotype a collection of normal inbred
mouse strains. The objectives of our studies were to determine and measure differences in quantitative mandibular traits/variables within and between different inbred mouse
strains, and to assess sexual di1norphism through bilateral measuren1ents of the
hemimandibles. These studies were a component of the Mouse Phenome Project to
collect normal craniometric data from 12 genetically heterogeneous inbred strains
utilizing digital images from equal numbers of female and male mice at 7 to 8 weeks of age.
Our central hypothesis was that morphometric analysis of mandibular structures
from genetically disparate inbred mouse strains would reveal quantifiable differences.
The null hypothesis of no difference among the strains for 1nandibular measurements was
rejected. Overall, CAST/Ei and MOLF/Ei were consistently small in size measured by
body weight with small skeletal structures. There was no strong pattern of body weight
and site of skeletal size in the mid and heavy weighted strains. Evidence of sexual
dimorphism was supported. Overall, it appears males and females that have the least
significance between them are in the DBA/2J strain, followed by A/J. The strain with the
most significant difference between males and females is in the C3H/HeJ strain.
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Normal Mandibular Morphology of Inbred Mouse StrainsEdwards, Michelle Halum January 2004 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Even though the molecular events and pathways that underlie craniofacial development and morphogenesis are not fully understood, it is accepted that their orchestration is influenced by the interaction of genetic and environmental factors. Inbred mouse strains represent genetically homogenous groups of individuals. It is established that mice in one strain often differ quite remarkably from mice in other inbred strains. Those phenotypic differences make mice exceptional tools for the dissection of genetic factors that influence normal and abnormal craniofacial morphogenesis. While numerous investigations have focused on abnormal morphogenesis, a comprehensive study of normal craniometric morphology across multiple inbred strains of mice has not been previously performed. The Mouse Phenome Project, an international collaboration of investigators, was formed to systematically phenotype a collection of normal inbred mouse strains. The objectives of our studies were to determine and measure differences in quantitative mandibular traits/variables within and between different inbred mouse strains, and to assess sexual dimorphism through bilateral measurements of the hemimandibles. These studies were a component of the Mouse Phenome Project to collect normal craniometric data from 12 genetically heterogeneous inbred strains utilizing digital images from equal numbers of female and male mice at 7 to 8 weeks of age.
Our central hypothesis was that morphometric analysis of mandibular structures from genetically disparate inbred mouse strains would reveal quantifiable differences. The null hypothesis of no difference among the strains for mandibular measurements was rejected. Overall, CAST/Ei and MOLF/Ei were consistently small in size measured by body weight with small skeletal structures. There was no strong pattern of body weight and site of skeletal size in the mid and heavy weighted strains. Evidence of sexual dimorphism was supported. Overall, it appears males and females that have the least significance between them are in the DBA/2J strain, followed by A/J. The strain with the most significant difference between males and females is in the C3H/HeJ strain.
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Ancillary methods to improve diagnostic accuracy of thyroid nodules on fine-needle aspiration cytology smearsVan Wyk, Christine 12 1900 (has links)
Thesis (MScMed (Dept. of Biomedical Sciences. Anatomy and Histology) --University of Stellenbosch, 2007. / Thyroid nodules are a common clinical problem encountered by physicians, surgeons and radiologists who deal with the head and neck region. However, most follicular lesions of the thyroid are benign, so that the indications for surgery should be as accurate as possible. The morphological difficulty on fine-needle aspiration biopsy (FNAB) of reliably distinguishing preoperatively between benign and malignant lesions has led to a search for ancillary methods that can assist with the diagnosis.
The aim of the first study was to develop a cytological scoring system to improve diagnostic accuracy of fine-needle aspiration biopsy of papillary carcinomas with special reference to the follicular variant of papillary carcinoma. The objective of the second study was the application of immunodiagnostic markers Galectin-3 and HBME-1 to histology tissue sections and their corresponding fine-needle aspiration cytology smears to assess their value in distinguishing benign from malignant thyroid lesions.
In the first study 16 different cytological features such as background, architecture and cellular morphology were quantatively assessed and scored. Only 14 of the 16 variables were statistically significant. The statistical analysis demonstrated that a score ≥ 4 was indicative of a papillary carcinoma with a sensitivity of 96%. A score < 4 suggested a benign multinodular goiter with a specificity of 97%.
In the second study Galectin-3 and HBME-1 were applied to histology tissue sections and their corresponding fine-needle aspiration cytology smears. Statistical analyses showed that the sensitivity of immunohistochemistry for diagnosing malignancy was better than the immunocytochemistry, but the specificity of immunocytochemistry was superior. Furthermore the diagnostic accuracy of immunohistochemistry (86%) and immunocytochemistry (88%) using co-expression of these two antibodies was excellent. In this study on immunocytochemistry, papillary carcinomas were clearly identified with a 100% co-expression in the classic and 71% in the follicular variant of papillary carcinoma. For the surgeon the identification of papillary carcinoma is critical, as this determines the extent of surgery. Similary, the confirmation of a non-neoplastic lesion may prevent surgery. In most cases follicular neoplasms, benign or malignant, will usually be excised for histopathology, prior to definite therapy.
These studies show that the implementation of ancillary methods such as a scoring system and immunodiagnostic markers can improve the diagnostic accuracy of thyroid fine-needle aspiration biopsies in our laboratory. This may lead to better management of thyroid nodules. However, it is advisable that cytopathologists always take all the clinical features and image analyses into consideration before making a diagnosis.
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The influence of mother care on the relationship between self-esteem and neural subtrates in young men and women : a neuroimaging studyWadiwalla, Mehereen. January 2007 (has links)
Introduction. Numerous studies have suggested that maternal care can influence the development and expansion of an individual's self-esteem. Yet the neural mechanisms of this relationship remain unexplored. Incidentally, it has already been demonstrated that a brain region, namely the Hippocampus (HC) is associated with both self-esteem and maternal care. Thus suggesting that there may be a three-way relationship. This also provided the impetus to speculate that a similar interaction could be observed in other brain regions like for example, the Dorsolateral Prefrontal cortex (DLPFC) and the Medial Prefrontal Cortex (MPFC). Therefore, the aim of this study is to scrutinize the possible relationship between mother care, self-esteem and neural correlates including the DLPFC, MPFC and HC, with emphasis on how normal variations in mother care could have consequences for the relationship between self-esteem and particularly the prefrontal cortices. Methods . Fifty-one subjects were recruited on the basis of their maternal scores, as assessed by the Parental Bonding Index and were consequently assigned to either a high mother care (MOCA) or low MOCA group. Their self-esteem was measured through various self-esteem scales including the Rosenberg self-esteem scale. The structural integrity of the regions was ascertained through the use of both manual and semi automated segmenting procedures. Results . Initial Bivariate correlations reported a negative association between DLPFC volumes and self-esteem in the high MOCA group while HC was positively associated with self-esteem in both high and low MOCA groups. There were no associations to report for the MPFC. Additional analysis revealed that the Biregional association was sex specific. Discussion. For the first time, we were successful in associating DLPFC volume with self-esteem. In addition, we successfully replicated the association between self-esteem and HC volume. This study could provide an indication how of maternal care could have a sex specific affect not only on the evolution of self-esteem, but also on the regions they may be targeting.
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The influence of mother care on the relationship between self-esteem and neural subtrates in young men and women : a neuroimaging studyWadiwalla, Mehereen. January 2007 (has links)
No description available.
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"Comparação anatômica entre o retalho perfurante ântero-lateral da coxa e os retalhos cutâneos paraescapular e lateral do braço" / Anatomical comparison of the anterolateral thigh perforator flap and the parascapular and lateral arm skin flapsBusnardo, Fabio de Freitas 01 September 2006 (has links)
A descrição de retalhos cutâneos pediculados em ramos perfurantes musculares é recente. O retalho ântero-lateral da coxa é vascularizado por vasos perfurantes musculares do ramo descendente da artéria circunflexa femoral lateral. Trata-se de retalho de pouca espessura, pedículo vascular longo e calibroso e baixa morbidade de área doadora. Entretanto, a dissecção do trajeto intramuscular de seu pedículo é tecnicamente difícil. Sua indicação é por vezes questionada por tratar-se de retalho de características semelhantes a outros vascularizados por artérias cutâneas diretas ou septocutâneas. Estes têm menor variação anatômica e dissecção mais simples. O presente estudo avaliou as características anatômicas do retalho ântero-lateral da coxa, através de dissecção em cadáveres frescos, comparando-as com as do retalho paraescapular e lateral do braço. Foram dissecados 60 retalhos (20 retalhos ântero-laterais da coxa, 20 paraescapulares e 20 retalhos laterais do braço) em 20 cadáveres frescos, não formolizados, com menos de 24 horas após o óbito. Todos os retalhos tiveram os seguintes parâmetros avaliados: comprimento do pedículo vascular, espessura do retalho, diâmetro do pedículo vascular arterial e venoso. Além disso, foi avaliada a presença de trajeto intramuscular do pedículo vascular (apenas nas dissecções do retalho ântero-lateral da coxa). A análise comparativa evidenciou que o pedículo vascular do retalho ântero-lateral da coxa é mais longo quando comparado aos dos retalhos paraescapular e lateral do braço (p<0,001). O retalho cutâneo lateral do braço apresenta a menor espessura (p<0,001) e o menor diâmetro arterial e venoso do pedículo vascular (p<0,001). Constatou-se a presença de trajeto intramuscular do pedículo do retalho ântero-lateral da coxa em 17 (85%) casos. O comprimento médio do segmento intramuscular do principal ramo perfurante foi de 4,13+2,02 cm. Os dados foram comparados e avaliados através de técnica de análise de variância com medidas repetidas. O nível de significância utilizado para os testes foi de 5%. As informações obtidas permitem concluir que o retalho ântero-lateral da coxa apresenta como vantagem o pedículo vascular de maior comprimento. Entretanto, apresentou em 85% dos casos a necessidade de dissecção intramuscular de um segmento deste pedículo. O retalho lateral do braço apresenta como principais características a pouca espessura e o menor diâmetro de seus pedículos vasculares. O retalho paraescapular tem características anatômicas semelhantes às do retalho ântero-lateral da coxa, não sendo evidenciada diferença significativa entre suas espessuras e diâmetros de seus pedículos vasculares. Apresenta pedículo vascular mais curto quando comparado ao do retalho ântero-lateral da coxa. Entretanto, trata-se de vaso septocutâneo, sem a necessidade de dissecção de trajeto intramuscular. / The description of the skin flaps based on perforator vessels is recent. The vascularization of the anterolateral thigh flap is based on perforator vessels coming from the lateral circumflex femoral artery. It has a thin skin paddle, a long and large vascular pedicle and low donor site morbidity. However, the dissection of the intramuscular path of its pedicle is technically difficult. Its indication is sometimes questionable since it is a flap with characteristics similar to others based on direct cutaneous or septocutaneous vessels, which have less anatomical variations and are easier to dissect. This study evaluated the anatomical characteristics of the anterolateral thigh perforator flap through the dissection of fresh cadavers, comparing them with those of the parascapular and lateral arm skin flap. Sixty flaps were dissected (20 anterolateral thigh, 20 parascapular and 20 lateral arm flaps) in 20 fresh cadavers, not perfused with formaldehyde, less than 24 hours after death. The following aspects were evaluated in all the flaps: length of the vascular pedicle, thickness of the flap and diameter of the arterial and venous vascular pedicle. Additionally, the presence of the intramuscular path of the vascular pedicle was evaluated (only in the dissections of the anterolateral thigh flap). The comparative analysis showed that the vascular pedicle of the anterolateral thigh perforator flap is longer when compared to those of the parascapular and lateral arm flaps (p<0,001). The lateral arm flap presented a pedicle with smaller arterial and venous diameter (p<0,001), in addition to being the thinner flap (p<0,001). It was verified that the vascular pedicle of the anterolateral thigh flap presented an intramuscular path in 17 (85%) cases. The average length of the intramuscular segment of the main perforator vessel was 4,13+2,02 cm. The data was compared and evaluated with variance analysis. The information obtained allows one to conclude that the advantage the anterolateral thigh perforator flap has over the other skin flaps is a longer vascular pedicle. However, the need for intramuscular dissection of a segment of this pedicle presented itself in 85% of the cases. The lateral arm flap is the thinnest flap, and the one with the smaller arterial and venous diameter of its vascular pedicle. The parascapular flap has anatomical characteristics similar to those of the anterolateral thigh flap, with no evidence of a significant difference between their thicknesses and diameters of vascular pedicles. Its vascular pedicle is shorter when compared to that of the anterolateral thigh flap. On the other hand, it is a fasciocutaneous vessel, without the need for intramuscular dissection.
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"Comparação anatômica entre o retalho perfurante ântero-lateral da coxa e os retalhos cutâneos paraescapular e lateral do braço" / Anatomical comparison of the anterolateral thigh perforator flap and the parascapular and lateral arm skin flapsFabio de Freitas Busnardo 01 September 2006 (has links)
A descrição de retalhos cutâneos pediculados em ramos perfurantes musculares é recente. O retalho ântero-lateral da coxa é vascularizado por vasos perfurantes musculares do ramo descendente da artéria circunflexa femoral lateral. Trata-se de retalho de pouca espessura, pedículo vascular longo e calibroso e baixa morbidade de área doadora. Entretanto, a dissecção do trajeto intramuscular de seu pedículo é tecnicamente difícil. Sua indicação é por vezes questionada por tratar-se de retalho de características semelhantes a outros vascularizados por artérias cutâneas diretas ou septocutâneas. Estes têm menor variação anatômica e dissecção mais simples. O presente estudo avaliou as características anatômicas do retalho ântero-lateral da coxa, através de dissecção em cadáveres frescos, comparando-as com as do retalho paraescapular e lateral do braço. Foram dissecados 60 retalhos (20 retalhos ântero-laterais da coxa, 20 paraescapulares e 20 retalhos laterais do braço) em 20 cadáveres frescos, não formolizados, com menos de 24 horas após o óbito. Todos os retalhos tiveram os seguintes parâmetros avaliados: comprimento do pedículo vascular, espessura do retalho, diâmetro do pedículo vascular arterial e venoso. Além disso, foi avaliada a presença de trajeto intramuscular do pedículo vascular (apenas nas dissecções do retalho ântero-lateral da coxa). A análise comparativa evidenciou que o pedículo vascular do retalho ântero-lateral da coxa é mais longo quando comparado aos dos retalhos paraescapular e lateral do braço (p<0,001). O retalho cutâneo lateral do braço apresenta a menor espessura (p<0,001) e o menor diâmetro arterial e venoso do pedículo vascular (p<0,001). Constatou-se a presença de trajeto intramuscular do pedículo do retalho ântero-lateral da coxa em 17 (85%) casos. O comprimento médio do segmento intramuscular do principal ramo perfurante foi de 4,13+2,02 cm. Os dados foram comparados e avaliados através de técnica de análise de variância com medidas repetidas. O nível de significância utilizado para os testes foi de 5%. As informações obtidas permitem concluir que o retalho ântero-lateral da coxa apresenta como vantagem o pedículo vascular de maior comprimento. Entretanto, apresentou em 85% dos casos a necessidade de dissecção intramuscular de um segmento deste pedículo. O retalho lateral do braço apresenta como principais características a pouca espessura e o menor diâmetro de seus pedículos vasculares. O retalho paraescapular tem características anatômicas semelhantes às do retalho ântero-lateral da coxa, não sendo evidenciada diferença significativa entre suas espessuras e diâmetros de seus pedículos vasculares. Apresenta pedículo vascular mais curto quando comparado ao do retalho ântero-lateral da coxa. Entretanto, trata-se de vaso septocutâneo, sem a necessidade de dissecção de trajeto intramuscular. / The description of the skin flaps based on perforator vessels is recent. The vascularization of the anterolateral thigh flap is based on perforator vessels coming from the lateral circumflex femoral artery. It has a thin skin paddle, a long and large vascular pedicle and low donor site morbidity. However, the dissection of the intramuscular path of its pedicle is technically difficult. Its indication is sometimes questionable since it is a flap with characteristics similar to others based on direct cutaneous or septocutaneous vessels, which have less anatomical variations and are easier to dissect. This study evaluated the anatomical characteristics of the anterolateral thigh perforator flap through the dissection of fresh cadavers, comparing them with those of the parascapular and lateral arm skin flap. Sixty flaps were dissected (20 anterolateral thigh, 20 parascapular and 20 lateral arm flaps) in 20 fresh cadavers, not perfused with formaldehyde, less than 24 hours after death. The following aspects were evaluated in all the flaps: length of the vascular pedicle, thickness of the flap and diameter of the arterial and venous vascular pedicle. Additionally, the presence of the intramuscular path of the vascular pedicle was evaluated (only in the dissections of the anterolateral thigh flap). The comparative analysis showed that the vascular pedicle of the anterolateral thigh perforator flap is longer when compared to those of the parascapular and lateral arm flaps (p<0,001). The lateral arm flap presented a pedicle with smaller arterial and venous diameter (p<0,001), in addition to being the thinner flap (p<0,001). It was verified that the vascular pedicle of the anterolateral thigh flap presented an intramuscular path in 17 (85%) cases. The average length of the intramuscular segment of the main perforator vessel was 4,13+2,02 cm. The data was compared and evaluated with variance analysis. The information obtained allows one to conclude that the advantage the anterolateral thigh perforator flap has over the other skin flaps is a longer vascular pedicle. However, the need for intramuscular dissection of a segment of this pedicle presented itself in 85% of the cases. The lateral arm flap is the thinnest flap, and the one with the smaller arterial and venous diameter of its vascular pedicle. The parascapular flap has anatomical characteristics similar to those of the anterolateral thigh flap, with no evidence of a significant difference between their thicknesses and diameters of vascular pedicles. Its vascular pedicle is shorter when compared to that of the anterolateral thigh flap. On the other hand, it is a fasciocutaneous vessel, without the need for intramuscular dissection.
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A histological and morphometric assessment of endocrine and ductular proliferation in the adult rat pancreas using an occlusive pancreatic duct ligation modelPage, Benedict J. (Benedict John) 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: Diabetes Mellitus (DM) is synonymous with "B-cell failure". Ligation of the pancreatic
duct distally to its confluence into the bile duct has been shown to induce endocrine
tissue regeneration from a number of probable sources. The cells responsible for
regeneration are supposed to possess either dormant pluripotent stem cell ability and/or
the plasticity to undergo metaplasia to form new and surplus endocrine tissue able to
replace pathologically and/or experimentally compromised pancreas. The sequence of
events (cell lineage) during this process of neogenesis, has been the source of
controversy for quite some time as various studies suggest that the cell lineage differs
from in vivo and in vitro studies, according to experimental model and species of
laboratory animal.
The object of this study was to utilise an established experimental laboratory animal
model to study islet morphological changes, neogenesis and or both in vivo. Further
aims of the study were to determine the extent, sequence and magnitude of pancreatic
duct ligation (PDL) induced endocrine neogenesis/morphogenesis in a laboratory rat
model using occlusive pancreatic duct ligation.
PDL's were performed on six groups of 25 normal adult Sprague-Dawley (SD) rats
(300g+) according to the method of Hultquist and Jonsson (1965). Experimental
animals were sacrificed at 12 hr intervals from day one post-PDL to day 10 and every
24 hrs thereafter to day 14 as described by Wang, Klëppel, Bouwens (1995). Animals
received BrdU (a thymidine marker and cell proliferation indicator) 50mglkg
intraperitoneally as described by Wang et al. (1995), one hour prior to removal of the
pancreas after which it was fixed in Bouin's solution and histologically processed.
Seven consecutive 3-6 urn thick serial sections were sequentially stained with H & E,
insulin (I), glucagon (G), somatostatin (ST), pancreatic polypeptide (PP), neuropeptide
tyrosine (NPY) and peptide tyrosine tyrosine (PYY). Immunolabeling was done
according to the method of Guesdon, Temynck , Avrameas (1979). Double
immunolabeling for BrdU and each pancreatic peptide was performed on the sections
on days 3,5, 7, 9 and 11 as described by Wang et al (1994). Cellular transformation between one and 3Yz days was characterised by simultaneous
total deletion and/or transdifferentiation of the acinar compartment and the appearance
of immunoreactive cells for I (11.53 ±1.5%), G (1.85 ±0.8%), pp (1.50 ±0.09%), and
ST (1.96 ±0.24%). Changes in the endocrine composition in existing islets, occurred
along a pathway that saw PP- and ST-cells invading the islet core, islet mantle glucagon
deletion and random appearance of all endocrine cell types within the inter-islet
interstitium on day 3Yz. Days 4 to 6Yz saw further endocrine expansion while days 7 to
14 were distinguished by islet reconstitution and consolidation. NPY immunoreactivity
appeared on day 4Y2 and persisted intermittently throughout while PVV first appeared
on day 4 and disappeared after day 7Yz.
The results suggest that PDL firstly induced the development of endocrine tissue
distributed haphazardly throughout the space previously occupied by acinar parenchyma.
Secondly, the appearance of insulin is preceded by the appearance of PP, glucagon and
somatostatin by 24-hours. A still to be determined proportion of the ligation induced
endocrine formation appeared to be associated with existing islets, resulting in a number
of very large islets, some of which might have secretory access through the glomerularlike
capillary network known to occupy the islet core. The remainder appeared to form
separate "new" islets, which have a dubious access to the blood stream.
In conclusion, if it is true that the pancreas can regenerate some of its endocrine tissue
then it has potential clinical implication for the stabilising of diabetes mellitus. Ligated
exocrine pancreatic tissue, devoid of its acinar component, has been shown to contain
notable quantities of insulin positive cells. This presents intriguing possibilities as an
alternative for donor tissue, usually obtained from rat foetuses, during foetal rat pancreas
transplantation studies. Pancreas tissue harvested from duct ligated rats could replace
the foetal tissue currently used in the treatment of experimental diabetes mellitus in
laboratory animals in this laboratory. / AFRIKAANSE OPSOMMING: Diabetes Mellitus is sinoniem met B-sel disfunksie. Endokriene regenerasie kan
segmenteel bewerkstellig word deur eksperimentele afbinding van die pankreasbuis
distaal tot sy samesmelting met die gemene galbuis. 'n Verskeidenheid van selle word
vermoedelik by hierdie proses betrek. Dormante stamselle besit die vermoë en/of
plastisiteit om 'n aantal vorms van metaplasie te ondergaan om nuwe en/of oortollige
endokriene weefsel te vorm wat patologiese en/of eksperimenteel gekompromiseerde
weefsel vervang. Die selontwikkelings volgorde wat tydens hierdie proses plaasvind
is al vir 'n geruime tyd die middelpunt van 'n meningsverskil. Sommige studies dui
daarop dat die in vivo selontwikkelingsvolgorde verskil van in vitro, volgens
eksperimentele model en tipe proefdier gebruik.
Die doel van die studie was die gebruik van 'n bestaande eksperimentele laboratorium
proefdier model om pankreas eiland morfologiese verandering en/ofneogenese of beide
in vivo te evalueer. Die oogmerk van die studie was om die omvang en volgorde van
veranderings in die endokriene kompartement (neogenese/morfogenese) te bepaal deur
gebruik te maak van 'n pankreas buis afbindings (PBA) model wat totale afsnyding van
die buis tot gevolg het.
PBA's is uitgevoer op ses groepe van 25 volwasse normale Sprague-Dawley (SD)
laboratorium rotte (±300g) soos beskryf deur Hultquist en Jonsson (1965). Proefdiere
is elke 12 uur geoffer vanaf dag een post-PBA tot dag tien en elke 24 uur daarna tot dag
14 soos beskryf deur Wang, Bouwens, Kloppel (1995) na die toediening van 50 mg/kg
5-Bromo-2-deoksi-uridien intraperitoneaal ('n selprolifererings aanduider) soos beskryf
deur Wang et al. (1995). Die pankreas is werwyder, in Bouin se oplossing gefikseer en
histologies geprosesseer. Sewe openvolgende seriesnitte (3-6 urn) is alternatiewelik
gekleur met H & E, en immunositochemies, soos beskryf deur Guesdon, Terugnek,
Avrameas (1979), vir insulien (I), glukagon (G), somatostatien (ST), pankreatiesepolipeptied
(PP), neuropeptied tirosien (NPY) en peptied tirosien-tirosien (PYY). BrdU
dubbel-immuunkleuring is ingesluit op dae 3,5, 7, 9 en 11 soos beskryf deur Wang et
al. (1994). Sellulêre transformasie tussen dae een en 3~ dae is gekenmerk deur gelyktydige en
totale uitwissing en/ofmetaplasie van die asinêre kompartement en die verskyning van
selle immunorektiefvir I(11.53 ±1.5%), G (1.85 ±0.8%), PP (1.50 ±0.09%), ST (1.96
±0.24%). Metaplasie was verantwoordelik vir merkbare veranderings in bestaande
endokriene weefsel langs In transformasie weg waar eiland insulien kemselle vervang
is deur PP- en ST-selle, glukagon buitelaag uitwissing en die toevallige verskyning van
alle endokriene seltipes in the inter-eiland interstitium teen dag 3Y2. Dae 4Y2deur 6~
is gekenmerk deur verdere endokrinetoename terwyl dag 7 deur 14 gekenmerk is deur
eiland hersamestelling en konsolidering. NPY immunoreaktiwiteit was vanaf dag 4~,
met afwisseling, te bespeur terwyl PVV slegs tussen dae 4 en 7 In verskyning gemaak
het.
. Die resultate suggereer eerstens, PBA induseer die ontwikkeling van oortollige
endokriene weefsel op In lukrake wyse versprei deur die ruimte voorheen deur asinêre
parenchiem beset. Tweedens, dat die verskyning van insulien deur dié van PP,
glukagon en somatostatien met minstens 24-uur voorafgegaan is. Die verhouding, van
nuutgevormde endokriene weefsel wat met bestaande eilande assosieer om In aantal baie
groot eilande te vorm, moet nog vasgestel word. Sulke strukture mag moontlik
afskeidings toegang hê tot die bloedstroom, deur die glomerulusagtige kapillêre netwerk,
in die eilandkern teenwoordig terwyl die oorblywende nuutgevormde endokrine weefsel
"nuwe" apparte eilande vorm wat wel of gladnie toegang tot die bloedstroom mag hê nie.
As gevolgtrekking, indien dit waar is dat volwasse pankreas eilandweefsel wel
regenerasie kan ondergaan, dan het dit kliniese implikasie vir die stabilisering van
diabetes mellitus. Weefsel verkry uit PBA bevat geen asinêre weefsel nie maar wel
merkbare hoeveelhede endokriene weefsel, veral insulin positief. Dit bied dan
interessante alternatiewe as skenker weefsel by fetal rot pankreas oorplantings. PBA
en/of die oorplanting van pankreasbuis afgebinde weefsel, na in vitro weefsel kultuur,
bied moontlikhede vir die behandeling van diabetes mellitus.
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