Unsuspected and extensive transmission of a drug-susceptible Mycobacterium tuberculosis strain

<p>Abstract</p> <p>Background</p> <p>A large and unsuspected tuberculosis outbreak involving 18.7% of the total of the tuberculosis cases studied, was detected in a population-based molecular epidemiological study performed in Zaragoza (Spain) from 2001 to 2004.</p> <p>Methods</p> <p>The <it>Mycobacterium tuberculosis </it>drug-susceptible strain, named <it>MTZ </it>strain, was genetically characterized by IS<it>6110</it>-RFLP, Spoligotyping and by MIRU-VNTR typing and the genetic patterns obtained were compared with those included in international databases. The characteristics of the affected patients, in an attempt to understand why the <it>MTZ </it>strain was so highly transmitted among the population were also analyzed.</p> <p>Results</p> <p>The genetic profile of the <it>MTZ </it>strain was rare and not widely distributed in our area or elsewhere. The patients affected did not show any notable risk factor for TB.</p> <p>Conclusion</p> <p>The <it>M. tuberculosis </it>strain <it>MTZ</it>, might have particular transmissibility or virulence properties, and we believe that greater focus should be placed on stopping its widespread dissemination.</p

Structure, location, function and pathological features of the human carotid body

Study of the structure, function and location of the carotid body is essential in the field of interventionist radiology since the exploration of these aspects with stents elicits a baroreceptor response, triggering in some cases unrecoverable vagotonic crises. This matter is of dual interest because massage in this zone (the bifurcation of the carotids) is one of the manoeuvres most frequently used in primary care in cases of sinusal paroxistic tachycardia. This organ changes with age, cellularity decreasing over time in a fashion inversely proportional to the amount of connective tissue, the cell clusters among them becoming increasingly distant from one another. In the present work, upon studying the structure of this body we observed different cell types and these could be classified as type I, or the main type, in turn divided into type A (pale) and type B (dark), surrounded by type II cells which acted as a support. As well as these, we observed paraneurons very similar to those of the autonomic nervous system. Inside these, Nissl granules were observed, in agreement with the extensive innervation to which this structure is subjected, like its vascularisation of capillaries and venules, where many contacts of glomic cells with nerves and with the vessels are observed. The large amount of neurotransmitters inside the body, encephalin, leucine and above all dopamine, makes the carotid body a good candidate for collecting the peptide necessary for the treatment of Parkinson's diseases or similar dyskinesias

Peculiarities of the thyroid gland structure (With special reference to the presence of ganglion zells)

We have perforined a study on the coirrparati\,e structure of the thyroid gland in several species OS mainmals (i-at, cat, dog, lamb, pig, cow, and rnan). We hnve described the structural differences among thein, paying special attention to the distribution of conncctive tissue. the intrafollicular and parafollicular cells. In the thyroid gland, we can confirm the existente of n e n e cclls. either isolated or forining vegetative cai-iglions in the iiitei-follicular spaces. in soine of the specie stiidied. especially in the rat and the dog

Elastin variations implicating in vascular smooth muscle cells phenotype in human tortuous arteries

The aim of the present work was to study the morphological implications between the elastin and the phenotypic expression of the vascular smooth muscle cells. For this purpose, sixty human tortuous arteries from different territories have been studied. We have measured the morphometric indexes Intimal Thickening Index and Elastolyse Index and they have been quantified with computer system analysis, image-colour corresponding to the orcein and Verhoeff reactions for detecting elastin and the a-actin in the smooth muscle cells. We compared both territorial arteries from the cranial and from abdominal origin. The elastin concentration was similar in both territories, but not its morphology according to its spatial distribution. We have observed a relationship between the elastin structural organisation from the media of arteries and of the internal elastic lamina in these territories and the variation of reactivity to the smooth muscle a-actin as a marker of the phenotypic state.Our results confirm the hypothesis that elastin, besides intervening in the architecture of the arterial wall, is a factor implicated in the phenotypic variability of the smooth muscle cells and in the development and evolution of the intimal thickenings in human atherosclerosis

Facial artery and atherosclerosis

We have performed a study about the incidence of the atherosclerotic phenomenon in the human facial artery, having observed an increase with aging. We also have researched the role of the smooth muscle cells in its genesis, with morphological, ultrastructural and immunohistochemical techniques

Experimental vasectomy and testicular structure

We have performed an experimental study on rats and dogs to evaluate the long term effects (from 1 to 12 months) of vasectomy on the structure of the testis. From four months after vasectomy onwards, the specimens showed very important changes in the seminiferous epithelium and Sertoli cells, with an obvious thickening of the basement membrane that supports the epithelium. The deterioration depended on the time passed and, over six months after vasectomy, the alterations were very clear and the seminiferous tubules became atrophic and shnink, sometimes without any remains of seminiferous epithelium and with an important hypertrophy of the interlobular interstitial tissue, although we did not see an increase in the number of Leydig cells. Alterations due to vasectomy depend on the animal species, the peculiarities of techniques and, of course, the time passed after surgery

Effect of endurance running on cardiac and skeletal muscle in rats

We studied the effect of resistance running on left cardiac ventricle size and rectus femoris muscle fiber composition. Ten male Wistar rats were trained on a treadmill 6 days per week for 12 weeks. Ten rats remained sedentary and served as controls. A higher endurance time (40%) and cardiac hypertrophy in the trained animals were indicators of training efficiency. Morphometric analysis of the left ventricle crosssectional area, left ventricular wall, and left ventricular cavity were evaluated. The endurance-running group demonstrated a hypertrophy of the ventricular wall (22%) and an increase in the ventricular cavity (25%); (pc0.0001). Semi-quantitative analysis of rectus femoris fiber-type composition and of the oxidative and glycolytic capacity was histochemically performed. Endurance running demonstrated a significant (pc0.01) increase in the relative frequency of 5 p e 1 (24%), Qpe IIA (8%) and 5 p e IIX (16%) oxidative fibers, and a decrease in Qpe IIB (20%) glycolytic fibers. There was a hypertrophy of both oxidative and glycolytic fiber types. The relative cross-sectional area analysis demonstrated an increase in oxidative fibers and a decrease in glycolytic fibers (p&lt;0.0001). Changes were especially evident for 'Qpe IIX oxidative-glycolytic fibers. The results of this study indicate that the left ventricle adapts to endurance running by increasing wall thickness and enlargement of the ventricular cavity. Skeletal muscle adapts to training by increasing oxidative fiber 'Qpe. This increase may be related to fiber transformation from Qpe IIB glycolytic to Qpe IIX oxidative fibers. These results open the possibility for the use of this type of exercise to prevent muscular atrophy associated with age or post-immobilization

Elastin variations implicating in vascular smooth muscle cells phenotype in human tortuous arteries

The aim of the present work was to study the morphological implications between the elastin and the phenotypic expression of the vascular smooth muscle cells. For this purpose, sixty human tortuous arteries from different territories have been studied. We have measured the morphometric indexes Intimal Thickening Index and Elastolyse Index and they have been quantified with computer system analysis, image-colour corresponding to the orcein and Verhoeff reactions for detecting elastin and the a-actin in the smooth muscle cells. We compared both territorial arteries from the cranial and from abdominal origin. The elastin concentration was similar in both territories, but not its morphology according to its spatial distribution. We have observed a relationship between the elastin structural organisation from the media of arteries and of the internal elastic lamina in these territories and the variation of reactivity to the smooth muscle a-actin as a marker of the phenotypic state. Our results confirm the hypothesis that elastin, besides intervening in the architecture of the arterial wall, is a factor implicated in the phenotypic variability of the smooth muscle cells and in the development and evolution of the intimal thickenings in human atherosclerosis

Effect of endurance running on cardiac and skeletal muscle in rats

We studied the effect of resistance running on left cardiac ventricle size and rectus femoris muscle fiber composition. Ten male Wistar rats were trained on a treadmill 6 days per week for 12 weeks. Ten rats remained sedentary and served as controls. A higher endurance time (40%) and cardiac hypertrophy in the trained animals were indicators of training efficiency. Morphometric analysis of the left ventricle crosssectional area, left ventricular wall, and left ventricular cavity were evaluated. The endurance-running group demonstrated a hypertrophy of the ventricular wall (22%) and an increase in the ventricular cavity (25%); (pc0.0001). Semi-quantitative analysis of rectus femoris fiber-type composition and of the oxidative and glycolytic capacity was histochemically performed. Endurance running demonstrated a significant (pc0.01) increase in the relative frequency of 5 p e 1 (24%), Qpe IIA (8%) and 5 p e IIX (16%) oxidative fibers, and a decrease in Qpe IIB (20%) glycolytic fibers. There was a hypertrophy of both oxidative and glycolytic fiber types. The relative cross-sectional area analysis demonstrated an increase in oxidative fibers and a decrease in glycolytic fibers (p<0.0001). Changes were especially evident for 'Qpe IIX oxidative-glycolytic fibers. The results of this study indicate that the left ventricle adapts to endurance running by increasing wall thickness and enlargement of the ventricular cavity. Skeletal muscle adapts to training by increasing oxidative fiber 'Qpe. This increase may be related to fiber transformation from Qpe IIB glycolytic to Qpe IIX oxidative fibers. These results open the possibility for the use of this type of exercise to prevent muscular atrophy associated with age or post-immobilization