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Septum
Kinds of Septum Terms modified by Septum Selected AbstractsThe influence of interfering septa on the incidence of Schneiderian membrane perforations during maxillary sinus elevation surgery: a retrospective study of 52 consecutive lateral window proceduresORAL SURGERY, Issue 1 2009S. Malkinson Abstract Aim:, Sinus lifts are a predictable method of augmenting the height of bone in maxillary posterior sextants. These procedures can be complicated by anatomical factors, such as the presence of interfering bony septa in the sinus. The objectives of this study were to investigate the incidence of interfering septa in patients undergoing sinus lifts and to see if the presence of interfering septa increased the chance of intra-operative membrane perforation. Materials and methods:, This retrospective cohort study assessed presence of interfering antral septa and their effect on Schneiderian membrane elevation in 45 patients with pneumatised sinuses undergoing sinus lifts. Chart audits and radiographic assessments were performed for 52 surgeries. The sinus lift procedure followed established guidelines. Presence of septa and occurrence of perforations were noted, and when perforations occurred, they were repaired with resorbable membranes. Results:, Septa were present in 40% of cases, and were found to be ,interfering' septa in 28.8% of cases. Membrane perforation occurred in 11.5% of cases. There was no statistically significant association between the presence of interfering septa and membrane perforation. Conclusion:, With enough experience and appropriate armamentarium and technique, an operator can overcome the presence of an interfering antral septum during a sinus lift procedure such that it does not increase the chance of perforating the Schneiderian membrane during elevation. [source] Late Presenters with Dextro-transposition of Great Arteries and Intact Ventricular Septum: To Train or Not to Train the Left Ventricle for Arterial Switch Operation?CONGENITAL HEART DISEASE, Issue 6 2009Noor Mohamed Parker MBChB ABSTRACT Objective., We report our experience in managing late presenters (older than 4 weeks) with dextro-transposition of great arteries and intact ventricular septum (d-TGA/IVS) in an effort to achieve successful arterial switch operation (ASO) in a third world setting. Design., We retrospectively reviewed the charts of all late presenters with d-TGA/IVS. Patients were divided into two groups: left ventricular training (LVT) group and non-left ventricular training (non-LVT) group. LVT group underwent pulmonary artery banding and Blalock-Taussig Shunt prior to ASO. Results., Twenty-one late presenters were included in the study. In LVT group, 11 patients with median age of 6 months (range, 1,72 months) underwent LVT. Later, 8 patients with median age of 9.25 months (range, 1.33,84 months) underwent ASO. Prior to ASO, left ventricle (LV) collapse resolved in all and left ventricle to systemic pressure (LV/SP) ratio was 0.81 (range, 0.76,0.95) in 4 patients. Two patients who had LVT for ,14 days required postoperative extracorporeal membrane oxygenation (ECMO) support due to LV dysfunction. Seven patients survived to discharge. In non-LVT group, 10 patients with median age of 2.5 months (range, 1,98 months) underwent ASO. Five patients had LV collapse, and median LV/SP ratio was 0.67 (range, 0.56,1.19) in 5 patients. Seven patients needed ECMO support. Seven patients survived to discharge. Conclusion., Late presenters with d-TGA/IVS, who have LV collapse on echocardiography and/or a LV/SP ratio <0.67 on cardiac catheterization, should be subjected to LVT preferably for duration of longer than 14 days in order to avoid potential ECMO use. [source] Sinus of Valsalva Aneurysm with Dissection into the Interventricular SeptumECHOCARDIOGRAPHY, Issue 1 2008Maria do Carmo P. Nunes M.D., Ph.D. No abstract is available for this article. [source] Morphologic Characteristics of the Left Atrial Appendage, Roof, and Septum: Implications for the Ablation of Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2006WANWARANG WONGCHAROEN M.D. Introduction: The left atrium (LA) ablation in different regions, including LA appendage (LAA), LA roof, and LA septum, has recently been proposed to improve the success rate of treating patients with atrial fibrillation (AF). The purpose of this study was to investigate the anatomy of LAA, LA roof, and LA septum, using computed tomography (CT). Methods and Results: Multidetector CT scan was used to depict the LA in 47 patients with drug-refractory paroxysmal AF (39 males, age = 50 ± 12 years) and 49 control subjects (34 males, age = 54 ± 11 years). The area of LAA orifice, neck, and the length of roof line were greater in AF group than in control subjects. Three types of LAA locations and two types of LAA ridges were observed. Higher incidence of inferior LAA was noted in AF patients. The different morphologies of LA roof were described. Roof pouches were revealed in 15% of AF and 14% of controls. Moreover, we found septal ridge in 32% of AF and 23% of controls. Conclusions: Considerable variations of LAA and LA roof morphologies were demonstrated. Peculiar structures, including roof pouches and septal ridges, were delineated by CT imaging. These findings were important for determining the strategy of AF ablation and avoiding the procedure-related complications. [source] Atrial Tachycardia Originating from the Upper Left Atrial Septum: Demonstration of Transseptal Interatrial Conduction Using the Infolded Atrial WallsJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2006KOJI KUMAGAI M.D. We report a rare case of atrial tachycardia (AT) originating from the upper left atrial septum. Electroanatomic mapping of both atria demonstrated that the earliest atrial activation during AT occurred at the upper left atrial septum 26 msec before the onset of the P wave, followed by the mid-right atrial septum (10 msec before the onset of the P wave) and then the upper right atrial septum just adjacent to the left septal AT site (1 msec before the onset of the P wave), indicating detour pathway conduction from the upper left to the upper right atrium. Embryologically, it was suggested that the superior components of the secondary atrial septum are made by the infolded atrial walls and could develop a transseptal detour pathway involving the left-side atrial septal musculature, the superior rim of the oval fossa and the right-side atrial septal musculature. A single radiofrequency application targeting the upper left atrial septum successfully abolished the AT. [source] New Technique for Fenestration of the Interatrial SeptumJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 4 2006MUTHUKUMARAN SIVAPRAKASAM M.R.C.P.C.H. Achieving controlled flow between the systemic and pulmonary venous circulations is desirable in many complex congenital heart diseases. This includes the Fontan circulation, primary pulmonary hypertension, double inlet ventricles, or hypoplastic left heart with obstruction to the atrioventricular valve. As no specific device is available for this purpose, we developed a balloon-mounted stent technique to achieve a predetermined-sized fenestration of an atrial baffle in a patient with Fontan circulation. The details of the technique are described. [source] Collaborative Approach in the Management of Pulmonary Atresia with Intact Ventricular SeptumJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 3 2001F.R.C.P.Article first published online: 8 JUN 200, SHAKEEL A. QURESHI M.B.Ch.B. [source] Pacing from the Right Ventricular Septum: Is There a Danger to the Coronary Arteries?PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 7 2009ANDREW W. TEH M.B.B.S. Background: Pacing from right ventricular (RV) septal sites has been suggested as an alternative to RV apical pacing in an attempt to avoid long-term adverse consequences on left ventricular function. Concern has been raised as to the relationship of the left anterior descending coronary artery (LAD) to pacing leads in these positions. Methods and Results: We retrospectively analyzed three cases in which patients with RV active-fixation leads in situ also had coronary angiography. Multiple fluoroscopic views were used to determine the relationship of the lead tip at various pacing sites to the coronary arteries. A lead placed on the anterior wall was in close proximity to the LAD, whereas septal and free wall positioning was not. Conclusion: Placement of RV active-fixation leads on the septum avoids potential coronary artery compromise. [source] Cartilage Regeneration in the Rabbit Nasal Septum,THE LARYNGOSCOPE, Issue 10 2006Meghann L. Kaiser MD Abstract Objective: Rhinoplasty frequently includes harvesting of nasal septal cartilage. The objective of this prospective basic investigation is to determine whether cartilage can regenerate after submucosal resection (SMR) of the nasal septum in the rabbit. Neocartilage formation has not heretofore been described in this model. Methods: By lateral rhinotomy, SMR was performed on 17 rabbits followed by reapproximation of the perichondrium. After 7 months, septi were fixed, sectioned, and examined histologically. Findings were photographed and data tabulated according to location and extent. Results: Sites of matrix-secreting isogenous chondrocyte islands were identified between the perichondrial flaps of every animal, principally in the anterior inferior septum. The width of the islands averaged 190 ,m, and the mean neocartilage height was found to be 840 ,m. The newly formed cartilage consisted of chondrocytes within chondrons and was comparable in shape and structure to native septal cartilage. Conclusions: After SMR, rabbit cartilage tissue can regenerate and form matrix within the potential space created by surgery. The surrounding stem cell-rich perichondrium may be the site of origin for these chondrocytes. These findings suggest that after SMR of the human nasal septum, it may be possible for new cartilage tissue to develop provided the mucosa is well approximated. This biologic effect may be enhanced by insertion of cytokine-rich tissue scaffolds that exploit the native ability of septal perichondrium to regenerate and repair cartilage tissue. [source] Normal Development of the Muscular Region of the Interventricular Septum.ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2009Summary In a first paper, we concluded that the muscular region of the interventricular septum is developed by the trabecular branches and showed evidence that the developing interventricular septum elongates in a direction opposite to that of atria. Nevertheless, to date the literature is lacking precise information on the importance of myocardial proliferation not only in this process but also in the morphogenesis of the ventricular cavities. The aim of this study was to determine the spatial and temporal distribution of high-intensity foci of cycling myocytes in the ventricular region of the heart of chicken embryos during cardiac septation. Histological studies, detection of the proliferating cell nuclear antigen by light and confocal microscopy and flow cytometric analysis were carried out. The results corroborate that the developing interventricular septum grows in a direction opposite to that of atria. A remoulding mechanism that results in fenestrated trabecular sheets and trabecular branching is discussed. Our findings allowed us to summarize the normal morphogenesis of the muscular region of the interventricular septum in a way that is different from that suggested by other researchers. [source] Restrictive Right Ventricular Physiology and Right Ventricular Fibrosis as Assessed by Cardiac Magnetic Resonance and Exercise Capacity After Biventricular Repair of Pulmonary Atresia and Intact Ventricular SeptumCLINICAL CARDIOLOGY, Issue 2 2010Xue-Cun Liang MD Background The hypertrophic myocardium, myocardial fiber disarray, and endocardial fibroelastosis in pulmonary atresia and intact ventricular septum (PAIVS) may provide anatomic substrates for restrictive filling of the right ventricle. Hypothesis Restrictive right ventricle (RV) physiology is related to RV fibrosis and exercise capacity in patients after biventricular repair of PAIVS. Methods A total of 27 patients, age 16.5 ± 5.6 years, were recruited after biventricular repair of PAIVS. Restrictive RV physiology was defined by the presence of antegrade diastolic pulmonary flow and RV fibrosis assessed by late gadolinium enhancement (LGE) cardiac magnetic resonance. Their RV function was compared with that of 27 healthy controls and related to RV LGE score and exercise capacity. Results Compared with controls, PAIVS patients had lower tricuspid annular systolic and early diastolic velocities, RV global longitudinal systolic strain, systolic strain rate, and early and late diastolic strain rates (all P < 0.05). A total of 22 (81%, 95% confidence interval: 62%,94%) PAIVS patients demonstrated restrictive RV physiology. Compared to those without restrictive RV physiology (n = 5), these 22 patients had lower RV global systolic strain, lower RV systolic and early diastolic strain rates, higher RV LGE score, and a greater percent of predicted maximum oxygen consumption (all P < 0.05). Conclusion Restrictive RV physiology reflects RV diastolic dysfunction and is associated with more severe RV fibrosis but better exercise capacity in patients after biventricular repair of PAIVS. Copyright © 2010 Wiley Periodicals, Inc. [source] Understanding heart development and congenital heart defects through developmental biology: A segmental approachCONGENITAL ANOMALIES, Issue 4 2005Masahide Sakabe ABSTRACT The heart is the first organ to form and function during development. In the pregastrula chick embryo, cells contributing to the heart are found in the postero-lateral epiblast. During the pregastrula stages, interaction between the posterior epiblast and hypoblast is required for the anterior lateral plate mesoderm (ALM) to form, from which the heart will later develop. This tissue interaction is replaced by an Activin-like signal in culture. During gastrulation, the ALM is committed to the heart lineage by endoderm-secreted BMP and subsequently differentiates into cardiomyocyte. The right and left precardiac mesoderms migrate toward the ventral midline to form the beating primitive heart tube. Then, the heart tube generates a right-side bend, and the d-loop and presumptive heart segments begin to appear segmentally: outflow tract (OT), right ventricle, left ventricle, atrioventricular (AV) canal, atrium and sinus venosus. T-box transcription factors are involved in the formation of the heart segments: Tbx5 identifies the left ventricle and Tbx20 the right ventricle. After the formation of the heart segments, endothelial cells in the OT and AV regions transform into mesenchyme and generate valvuloseptal endocardial cushion tissue. This phenomenon is called endocardial EMT (epithelial-mesenchymal transformation) and is regulated mainly by BMP and TGF,. Finally, heart septa that have developed in the OT, ventricle, AV canal and atrium come into alignment and fuse, resulting in the completion of the four-chambered heart. Altered development seen in the cardiogenetic process is involved in the pathogenesis of congenital heart defects. Therefore, understanding the molecular nature regulating the ,nodal point' during heart development is important in order to understand the etiology of congenital heart defects, as well as normal heart development. [source] Cell adhesion in zebrafish myogenesis: Distribution of intermediate filaments, microfilaments, intracellular adhesion structures and extracellular matrixCYTOSKELETON, Issue 10 2008Manoel L. Costa Abstract To overcome the limitations of in vitro studies, we have been studying myogenesis in situ in zebrafish embryos, at a sub-cellular level. While in previous works we focused on myofibrillogenesis and some aspects of adhesion structures, here we describe in more detail cell adhesion structures and interactions among cytoskeletal components, membrane and extracellular matrix during zebrafish muscle development. We studied the intermediate filaments, and we describe the full range of desmin distribution in zebrafish development, from perinuclear to striated, until its deposition around the intersomite septa of older somites. This adhesion structure, positive for desmin and actin, has not been previously observed in myogenesis in vitro. We also show that actin is initially located in the intersomite septum region whereas it is confined to the myofibrils later on. While actin localization changes during development, the adhesion complex proteins vinculin, paxillin, talin, dystrophin, laminin and fibronectin always appear exclusively at the intersomite septa, and appear to be co-distributed, even though the extracellular proteins accumulates before the intracellular ones. Contrary to the adhesion proteins, that are continuously distributed, desmin and sarcomeric actin form triangular aggregates among the septa and the cytoskeleton. We studied the cytoskeletal linker plectin as well, and we show that it has a distribution similar to desmin and not to actin. We conclude that the in situ adhesion structures differ from their in vitro counterparts, and that the actual zebrafish embryo myogenesis is quite different than that which occurs in in vitro systems. Cell Motil. Cytoskeleton 65: 801,815, 2008. © 2008 Wiley-Liss, Inc. [source] Botanical Extracts Used in the Treatment of CelluliteDERMATOLOGIC SURGERY, Issue 2005Doris Hexsel MD Background. Cellulite is defined as skin relief alterations that give the skin an orange peel or mattress appearance. The lesions tend to be asymptomatic and may be considered the anatomic expressions of the structures in the affected area, such as the fat and subcutaneous septa. Objective. The present article reviews the most important botanical extracts used as active ingredients in the treatment of cellulite, as well as the steps to obtain these botanicals as raw material and their standardization and quality control, which are important to guarantee their therapeutic action. Methods. The current literature was reviewed, and we also obtained information from the manufacturers of the prducts that contained botanicals because of the few publications about this subject. Conclusions. The reduction in fat deposits through the continuous use of anticellulite products depends on the availability of the active ingredient at the action site, the concentration of the ingredient in the formulation, and the physiochemical characteristics particular to each active ingredient. The botanicals used in topical products must have standardized extracts, which would permit each phytomedicine to have the same effect anywhere in the world. New scientific research is necessary to verify the efficacy and ideal concentrations of such substances. DORIS HEXSEL, MD, CECILIA ORLANDI, MD, AND DEBORA ZECHMEISTER DO PRADO, PHARM, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. [source] Absence of tissue inhibitor of metalloproteinases 3 disrupts alveologenesis in the mouseDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 1 2009Sean E. Gill Tissue inhibitors of metalloproteinases (TIMPs) regulate extracellular matrix (ECM) degradation by matrix metalloproteinases (MMPs) throughout lung development. We examined lungs from TIMP3 null mice and found significant air space enlargement compared with wild type (WT) animals during a time course spanning early alveologenesis (post-partum days 1, 5, 9 and 14). Trichrome staining revealed a similar pattern of collagen distribution in the walls of nascent alveoli; however, the alveolar walls of TIMP3 mutant mice appeared to be thinner than controls. Assessment of MMP2 and MMP9 activities by gelatin zymography demonstrated a significant elevation in the active form of MMP2 at post-partum days 1 and 5. Treatment of null pregnant dams with a broad spectrum synthetic metalloproteinase inhibitor, GM6001, on embryonic day 16.5 enhanced the formation of primitive alveoli during the saccular stage of lung development as evidenced by a partial, but significant, rescue of alveolar size in post-partum day 1 animals. We propose that increased MMP activity in the absence of TIMP3 enhances ECM proteolysis, upsetting proper formation of primitive alveolar septa during the saccular stage of alveologenesis. Therefore, TIMP3 indirectly regulates alveolar formation in the mouse. To our knowledge, ours is the first study to demonstrate that in utero manipulation of the TIMP/MMP proteolytic axis, to specifically inhibit proteolysis, significantly affects lung development. [source] Characterization of molecular markers to assess cardiac cushions formation in XenopusDEVELOPMENTAL DYNAMICS, Issue 12 2009Young-Hoon Lee Abstract The valves and septa of the mature heart are derived from the cardiac cushions, which develop from discrete swellings in two regions of developing heart tube: the atrioventricular (AV) canal and the ventricular outflow tract (OFT). In higher vertebrates, three distinct lineages contribute to the heart valves and septa, the endocardium, the myocardium, and the cardiac neural crest that will populate the cardiac jelly of the OFT. Very little is known about cardiac cushions development in amphibians. Here, we describe the expression of eight genes during key stages of cardiac cushion development in Xenopus. Among these genes, the Wnt antagonist Frzb1 and the transcription factors Xl-Fli, Sox8, Sox9, and Sox10 are differentially expressed in the mesenchyme of the OFT and AV cushions. These genes can be used in combination with lineage-tracing experiments to determine the embryonic origin of the cardiac cushions mesenchyme in Xenopus. Developmental Dynamics 238:3257,3265, 2009. © 2009 Wiley-Liss, Inc. [source] The histology of the Upper Silurian osteostracan Timanaspis kossovoii Obruchev (Agnatha) from North Timan, RussiaACTA ZOOLOGICA, Issue 2009Olga B. Afanassieva Abstract The fine structure of the exoskeleton of Timanaspis kossovoii Obruchev 1962 was investigated based on new well-preserved material. The remains come from the lower part of the Eptarma Formation (Upper Silurian). Timanaspis kossovoii was referred by Obruchev to the family Tremataspididae and most authors agree with the placement of Timanaspis among tremataspidid osteostracans. Histological study of the shield of T. kossovoii has revealed the presence of unusual features in the exoskeletal structure. The smooth and shiny surface of the ventral side of the shield of T. kossovoii is similar to that of species of Tremataspis, but thin sections show differences in histological composition. The exoskeleton of T. kossovoii consists mainly of dense bony tissue in the middle layer and a laminated basal layer. No osteocyte cavities of typical form and size were found in the middle layer. The upper parts of the elongated tubercles of the dorsal side of the shield are formed by a well-developed dentine-like tissue; the arrangement of numerous tubules within this tissue is far more regular than in the mesodentine of Tremataspis. No traces of perforated septa, pore fields or a polygonal model were detected in the structure of the exoskeleton of Timanaspis. We conclude that Timanaspis can be differentiated from conventional tremataspidids by histological features and refer it to the new family Timanaspididae. Moreover, the Timanaspis exoskeleton provides evidence that an acellular condition of bony tissue does not appear to be characteristic of only Late Devonian osteostracans. [source] Effect of tributyltin on testicular development in Sebastiscus marmoratus and the mechanism involved,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2009Jiliang Zhang Abstract Organotin compounds, such as tributyltin (TBT), that have been used as antifouling biocides can induce masculinization in female mollusks. However, few studies addressing the effects of TBT on fishes have been reported. The present study was conducted to investigate the effects of TBT at environmentally relevant concentrations (1,10, and 100 ng/L) on testicular development in Sebastiscus marmoratus and to gain insight into its mechanism of action. After exposure for 48 d, the gonadosomatic index had decreased in a dose-dependent manner. Although the testosterone levels in the testes were elevated and the 17,-estradiol levels were decreased, spermatogenesis was suppressed. Moreover, ,-glutamyl transpeptidase activity (which is used as a Sertoli cell marker) was decreased in a dose-dependent manner after TBT exposure, and serious interstitial fibrosis was observed in the interlobular septa of the testes in the 100 ng/L TBT test group. Increases in the retinoid × receptors and peroxisome proliferator activated receptor , expression and the progressive enlargement of lipid droplets in the testes were observed after TBT exposure. Estrogen receptor , levels in the testes of the fish exposed to TBT decreased in a dose-dependent manner. The reduction of estrogen receptor , mRNA resulted from the decrease of 17,-estradiol levels, and the progressive enlargement of lipid droplets may have contributed to the dysfunction of the Sertoli cells, which then disrupted spermatogenesis. [source] Regional distribution of collagen and haemosiderin in the lungs of horses with exercise-induced pulmonary haemorrhageEQUINE VETERINARY JOURNAL, Issue 6 2009F. J. Derksen Summary Reasons for performing study: Regional veno-occlusive remodelling of pulmonary veins in EIPH-affected horses, suggests that pulmonary veins may be central to pathogenesis. The current study quantified site-specific changes in vein walls, collagen and haemosiderin accumulation, and pleural vascular profiles in the lungs of horses suffering EIPH. Hypothesis: In the caudodorsal lung regions of EIPH-affected horses, there is veno-occlusive remodelling with haemosiderosis, angiogenesis and fibrosis of the interstitium, interlobular septa and pleura. Methods: Morphometric methods were used to analyse the distribution and accumulation of pulmonary collagen and haemosiderin, and to count pleural vascular profiles in the lungs of 5 EIPH-affected and 2 control horses. Results: Vein wall thickness was greatest in the dorsocaudal lung and significantly correlated with haemosiderin accumulation. Increased venous, interstitial, pleural and septal collagen; lung haemosiderin; and pleural vascular profiles occurred together and changes were most pronounced in the dorsocaudal lung. Further, haemosiderin accumulation colocalised with decreased pulmonary vein lumen size. Vein wall thickening, haemosiderin accumulation and histological score were highly correlated and these changes occurred only in the caudodorsal part of the lung. Conclusion: The colocalisation of these changes suggests that regional (caudodorsal) venous remodelling plays an important role in the pathogenesis of EIPH. Potential relevance: The results support the hypothesis that repeated bouts of venous hypertension during strenuous exercise cause regional vein wall remodelling and collagen accumulation, venous occlusion and pulmonary capillary hypertension. Subjected to these high pressures, there is capillary stress failure, bleeding, haemosiderin accumulation and, subsequently, lung fibrosis. [source] Calcineurin is implicated in the regulation of the septation initiation network in fission yeastGENES TO CELLS, Issue 10 2002Yabin Lu Background: In fission yeast, calcineurin has been implicated in cytokinesis because calcineurin-deleted cells form multiple septa and cell separation is impeded. However, this mechanism remains unclear. Results: We screened for mutations that confer syn-thetic lethality with calcineurin deletion and isolated a mutant, its10-1/cdc7-i10, a novel allele of the cdc7+ gene involved in the septation initiation network (SIN). The mutation created a termination codon, resulting in the truncation of Cdc7 by 162 amino acids, which is not localized in the spindle pole body. Following treatment with the immune suppressive drug FK506, cdc7-i10 and the original cdc7-24 mutant cells showed highly elongated multinuclear morphology with few visible septa, closely resembling the phenotype at the restrictive temperature. Other SIN mutants, cdc11, spg1, sid2 and mob1 showed similar phenotypes following FK506 treatment. Consistent with this, expression of the constitutively active calcineurin suppressed the growth defects and septum initiation deficiency of these SIN mutants at the restrictive temperature. Moreover, electron microscopy revealed that calcineurin-deleted cells had very thick multiple septa which were partially and ectopically formed. Conclusion: These results suggest that calcineurin is involved in the regulation of the SIN pathway, and is required for the proper formation and maturation of the septum in fission yeast. [source] Leptin-mediated neovascularization is a prerequisite for progression of nonalcoholic steatohepatitis in rats,HEPATOLOGY, Issue 4 2006Mitsuteru Kitade Nonalcoholic steatohepatitis (NASH) may cause fibrosis, cirrhosis, and hepatocellular carcinoma (HCC); however, the exact mechanism of disease progression is not fully understood. Angiogenesis has been shown to play an important role in the progression of chronic liver disease. The aim of this study was to elucidate the role of angiogenesis in the development of liver fibrosis and hepatocarcinogenesis in NASH. Zucker rats, which naturally develop leptin receptor mutations, and their lean littermate rats were fed a choline-deficient, amino acid,defined diet. Both Zucker and littermate rats showed marked steatohepatitis and elevation of oxidative stress markers (e.g., thiobarbital acid reactive substances and 8-hydroxydeoxyguanosine). In sharp contrast, liver fibrosis, glutathione- S -transferase placental form (GST-P)-positive preneoplastic lesions, and HCC developed in littermate rats but not in Zucker rats. Hepatic neovascularization and the expression of vascular endothelial growth factor (VEGF), a potent angiogenic factor, only increased in littermate rats, almost in parallel with fibrogenesis and carcinogenesis. The CD31-immunopositive neovessels were mainly localized either along the fibrotic septa or in the GST-P,positive lesions. Our in vitro study revealed that leptin exerted a proangiogenic activity in the presence of VEGF. In conclusion, these results suggest that leptin-mediated neovascularization coordinated with VEGF plays an important role in the development of liver fibrosis and hepatocarcinogenesis in NASH. (HEPATOLOGY 2006;44:983,991.) [source] S-100-negative atypical granular cell tumor: report of a caseINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 3 2002Mi-Woo Lee MD A 38-year-old man presented with a solitary, round, 1.2 × 1.2 cm, bluish-colored, dome-shaped, hard nodule on the left side of the neck, which had grown over 2 months (Fig. 1). The nodule was nontender and nonmovable. Light microscopy revealed that the neoplasm was situated in the reticular dermis with extension into the papillary dermis. The tumor showed expansile growth with smooth and round borders, and was made up of sheets of cells arranged in nests or lobules separated by thin delicate connective tissue septa. The tumor cells were round, oval, or polygonal in shape with distinct cellular borders. The cells had abundant eosinophilic granular cytoplasm, and considerable variation of cellular and nuclear size was noted (Fig. 2a). The tumor cell nuclei were vesicular and some had pleomorphism (Fig. 2b). Sometimes multiple nucleoli were seen. Mitoses and necrosis were virtually absent. Immunohistochemical staining revealed that some of the cytoplasmic granules stained positively with periodic acid,Schiff (PAS) after diastase treatment. Tumor cells showed strong reactivity for CD68 and neuron-specific enolase, and negative results for S-100, factor XIIIa, cytokeratin, desmin, CD34, and smooth muscle actin. Electron microscopy revealed that the tumor was composed of polygonal cells with round to irregular nuclei, and the cytoplasm contained numerous secondary lysosomes. The tumor was completely excised. Figure 1. A solitary, round, 1.2 × 1.2 cm, bluish-colored, dome-shaped, hard nodule on the left side of the neck Figure 2. (a) Tumor cells contain granular cytoplasm and show atypical cytologic features (b) Neoplastic cells show variation of cell size and nuclear pleomorphism [source] Correlation between gross anatomical topography, sectional sheet plastination, microscopic anatomy and endoanal sonography of the anal sphincter complex in human malesJOURNAL OF ANATOMY, Issue 2 2009S. Al-Ali Abstract This study elucidates the structure of the anal sphincter complex (ASC) and correlates the individual layers, namely the external anal sphincter (EAS), conjoint longitudinal muscle (CLM) and internal anal sphincter (IAS), with their ultrasonographic images. Eighteen male cadavers, with an average age of 72 years (range 62,82 years), were used in this study. Multiple methods were used including gross dissection, coronal and axial sheet plastination, different histological staining techniques and endoanal sonography. The EAS was a continuous layer but with different relations, an upper part (corresponding to the deep and superficial parts in the traditional description) and a lower (subcutaneous) part that was located distal to the IAS, and was the only muscle encircling the anal orifice below the IAS. The CLM was a fibro-fatty-muscular layer occupying the intersphincteric space and was continuous superiorly with the longitudinal muscle layer of the rectum. In its middle and lower parts it consisted of collagen and elastic fibres with fatty tissue filling the spaces between the fibrous septa. The IAS was a markedly thickened extension of the terminal circular smooth muscle layer of the rectum and it terminated proximal to the lower part of the EAS. On endoanal sonography, the EAS appeared as an irregular hyperechoic band; CLM was poorly represented by a thin irregular hyperechoic line and IAS was represented by a hypoechoic band. Data on the measurements of the thickness of the ASC layers are presented and vary between dissection and sonographic imaging. The layers of the ASC were precisely identified in situ, in sections, in isolated dissected specimens and the same structures were correlated with their sonographic appearance. The results of the measurements of ASC components in this study on male cadavers were variable, suggesting that these should be used with caution in diagnostic and management settings. [source] Tissue reaction and biodegradation of implanted cross-linked high amylose starch in ratsJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 6 2002Cyril Désévaux Abstract The biocompatibility and degradation characteristics of cross-linked high amylose starch (Contramid®) were investigated in rats over 4 months. Contramid® pellets (3-mm diameter and thickness) obtained by direct compression, were implanted subcutaneously and intramuscularly. On sequential time points, macroscopic observations of implantation sites were performed and tissue samples were removed, fixed, and histologically evaluated. No macroscopic inflammatory reaction was observed with Contramid®. Upon histologic examination, inflammatory reaction produced by Contramid® was moderate and restricted to implantation sites. The sequence of inflammatory events with Contramid® was similar regardless of implantation site. Degradation of Contramid® pellets was characterized by fragmentation with formation of fibrovascular septa and phagocytosis by macrophages. Finally Contramid® was mostly absorbed by the end of the 4-month period and substituted by adipocytes. It has been demonstrated that Contramid® is a biocompatible and absorbable material. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res (Appl Biomater) 63: 772,779, 2002 [source] Role of Structural Complexities of Septal Tissue in Maintaining Ventricular Fibrillation in Isolated, Perfused Canine VentricleJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 1 2001TAKANORI IKEDA M.D. Tissue Structure and VF.Introduction: It is unclear how the patterns of wavelet propagation during ventricular fibrillation (VF) vary between structurally different tissues. We hypothesized that the structural complexities of septal tissue influence the maintenance of reentrant wavelets in the ventricle. Methods and Results: Endocardial activation patterns during VF were analyzed in the isolated, perfused canine right ventricular (RV) free wall (n = 9), interventricular septum (n = 5), and left ventricular (LV) free wall (n = 6) using a computerized mapping system (2-mm resolution) with 120-msec consecutive windows. Each tissue sample was cut progressively to reduce the tissue mass until the VF was terminated. More wavelets were seen in the septa than in the RV and LV free walls at baseline (P = 0.004), and VF in the septa displayed a shorter cycle length than in the RV and LV free walls (P = 0.017). As the tissue mass decreased, VF became successively more organized in all regions: the number of wavelets decreased and the cycle length of VF lengthened. Single and "figure-of-eight" stationary, reentrant wavelets often were mapped after tissue mass reduction in the RV free walls and rarely in the LV free walls, but they were not observed in the septa. Less critical mass was required to maintain VF in the septa than in the RV and LV free walls (P = 0.0006). Gross anatomic and histologic examinations indicated that the tissue structure of the septa is more complex than that of the RV and LV free walls. Conclusion: VF activation patterns with progressive reduction of tissue mass differ for the septum and the ventricular free walls. The structural complexities of the septal tissue influence the maintenance of fibrillation in the ventricle. [source] Borderline cystic tumors of the ovary: Gray-scale and color Doppler sonographic findingsJOURNAL OF CLINICAL ULTRASOUND, Issue 2 2002M. Angela Pascual MD Abstract Purpose The aim of the study was to determine the value of gray-scale and color Doppler sonography in distinguishing borderline cystic tumors (BCTs) from benign cysts and malignant tumors of the ovary. Methods The gray-scale and color Doppler sonographic features of 383 ovarian lesions in 374 nonpregnant women were retrospectively studied. Sonography was performed transvaginally for all but 7 lesions, which were imaged suprapubically. All of the lesions were surgically resected via laparoscopy or laparotomy. Results The histopathologic diagnoses were 27 BCTs, 35 ovarian carcinomas, and 321 benign cysts. Sonography diagnosed 24 (89%) of 27 BCTs as malignant lesions. Patients with BCTs, were younger than those with ovarian cancer (p < 0.001). BCTs showed intracystic papillae in 17 cases (63%), diffuse internal echoes in 11 (41%), intracystic septa in 8 (30%), a heterogeneous echo pattern in 7 (26%), and a solid pattern in 4 (15%). BCTs showed blood flow in 24 cases (89%) and lower pulsatility and resistance indices (RI) compared with benign lesions (p < 0.001 for both). Multivariate analysis revealed intracystic papillae as the only independent predictor of BCTs (p < 0.001). Conclusions When a cystic mass has papillae, this is the only abnormal finding detected by gray-scale transvaginal sonography, and color Doppler imaging shows low RI values within the mass, a BCT should be suspected. © 2002 John Wiley & Sons, Inc. J Clin Ultrasound 30:76,82, 2002; DOI 10.1002/jcu.10028 [source] Gadolinium-Induced Nephrogenic Systemic Fibrosis Is Associated with Insoluble Gd Deposits in Tissues: In Vivo Transmetallation Confirmed by MicroanalysisJOURNAL OF CUTANEOUS PATHOLOGY, Issue 12 2009Charu Thakral Background: Nephrogenic systemic fibrosis (NSF) is an extremely debilitating systemic fibrosing disorder affecting renal failure patients. The association of NSF with gadolinium (Gd) containing magnetic resonance contrast agents was noted in 2006. Gd deposition in skin biopsies was demonstrated shortly thereafter. Methods: We used automated scanning electron microscopy (SEM)/energy dispersive x-ray spectroscopy for in situ quantitative analysis of insoluble Gd-containing deposits, recording multi-elemental composition and spatial distribution of detected features. Results: Gd was detected in all 29 patients (53 of 57 skin biopsies) with NSF, biopsied from 2 weeks to 3 years after Gd exposure. Gd concentration ranged from 1 to 2270 cps/mm2 and was detected predominantly in the deep dermis and subcutaneous fibrous septa. Gd was found associated with Ca, P and sometimes Fe or Zn. Patients with sequential biopsies showed persistence or increase of Gd in tissues (6 of 11). Transmission electron microscopy (TEM) identified the intracellular deposits in fibrocytes and macrophages. Conclusions: The demonstration of insoluble tissue deposits of Gd with co-associated elements clearly confirms in vivo transmetallation and dissociation of soluble Gd-chelates. Toxic Gd3+ may trigger fibrosis under permissive conditions, e.g., in renal insufficiency. Pathologists and clinicians need to be aware of this serious but preventable disease. [source] Phylogeny of Medusozoa and the evolution of cnidarian life cyclesJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 3 2002A. G. Collins To investigate the evolution of cnidarian life cycles, data from the small subunit of the ribosome are used to derive a phylogenetic hypothesis for Medusozoa. These data indicate that Cnidaria is monophyletic and composed of Anthozoa and Medusozoa. While Cubozoa and Hydrozoa are well supported clades, Scyphozoa appears to be paraphyletic. Stauromedusae is possibly the sister group of either Cubozoa or all other medusozoans. The phylogenetic results suggest that: the polyp probably preceded the medusa in the evolution of Cnidaria; within Hydrozoa, medusa development involving the entocodon is ancestral; within Trachylina, the polyp was lost and subsequently regained in the parasitic narcomedusans; within Siphonophorae, the float originated prior to swimming bells; stauromedusans are not likely to be descended from ancestors that produced medusae by strobilation; and cubozoan polyps are simplified from those of their ancestors, which possessed polyps with gastric septa and four mesogleal muscle bands and peristomial pits. [source] Transverse sinus septum: A new aetiology of idiopathic intracranial hypertension?JOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 2 2004Rathan M Subramaniam Summary A venographic cryptic stenosis at the junction of middle and lateral third of the transverse sinus has been observed in patients suffering from idiopathic intracranial hypertension. After reviewing the anatomical and embryological literature of the transverse sinus, 20 transverse sinuses were explored (in a pilot study of 10 human cadavers) in order to determine the anatomical basis of this stenosis. The presence of septa of varying sizes was observed. We conclude that the presence of a large septum is one of the causes of venographic cryptic stenosis observed in these patients and might be one of the aetiological factors involved in idiopathic intracranial hypertension. [source] The heart of the South American rattlesnake, Crotalus durissusJOURNAL OF MORPHOLOGY, Issue 9 2010Bjarke Jensen Abstract Most anatomical and physiological studies of the sauropsid heart have focused on species with extraordinary physiologies, and detailed anatomical descriptions of hearts from sauropsids with more common physiologies are therefore warranted. Here, we present a comprehensive study of the cardiac anatomy of the South American rattlesnake (Crotalus durissus). The cardiovascular physiology of this species has been investigated in a number of studies, whereas only a few cursory studies exist on the cardiac anatomy of viperid snakes. The heart of C. durissus is typically squamate in many regards. Both atria are thin-walled sacs, and the right atrium is the most voluminous. The single ventricle contains three major septa; the vertical septum, the muscular ridge (MR), and the bulbuslamelle. These partially divide the ventricle into three chambers; the systemic and left-sided cavum arteriosum (CA), the pulmonary and right-sided cavum pulmonale, and the medial cavum venosum (CV). The MR is the most developed septum, and several additional and minor septa are found within the CA and CV. An extraordinary thin cortical layer encloses the ventricle, and it is irrigated by a remarkably rich arborization of coronary arteries. Previous studies show high degrees of blood flow separation in the Crotalus heart, and this can only be explained by the coordinated actions of the septa and the prominent atrioventricular valves. J. Morphol. 271:1066-1077, 2010. © 2010 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||||||||||||||