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Multiple Foci (multiple + focus)
Selected AbstractsFolding of the tectal cortex by local remodeling of neural differentiationDEVELOPMENTAL DYNAMICS, Issue 3 2004Tatsuo Mima Abstract The folding pattern of the brain cortex is a precisely regulated process, but the mechanism involved during development remains unclear. A proposed theory predicts that the initiation of cortical folding depends, at least partly, on nonuniform distribution of neuronal differentiation and neurite growth. We tested this theory experimentally, by remodeling the normal pattern of neuronal cell differentiation within the embryonic optic tectum. Multiple foci of activated fibroblast growth factor signaling were created in the tectal cortex to locally change the neural differentiation and axonal growth patterns. At these foci, tectal cells remained undifferentiated and their radial and tangential migration was suppressed. These local changes in the neuronal cell differentiation resulted in a conversion of the tectal cortex from smoothly extended into precociously folded. The results provide in vivo experimental evidence that microscopic changes in the neuronal cell differentiation pattern can induce or remodel the folding pattern of the brain cortex. Developmental Dynamics 229:475,479, 2004. © 2004 Wiley-Liss, Inc. [source] The relative importance of landscape and community features in the invasion of an exotic shrub in a fragmented landscapeECOGRAPHY, Issue 2 2006Anne M. Bartuszevige Although invasive plants are recognized as a major ecological problem, little is known of the relative importance of plant community characteristics versus landscape context in determining invasibility of communities. We determined the relative importance of community and landscape features of 30 woodlots in influencing the invasion of Lonicera maackii. We sampled woodlots using the point-quarter method and calculated canopy openness and basal areas and densities of shrub, sapling and tree species, as well as woody species richness. We used aerial photos and ArcView GIS to calculate landscape parameters from the same woodlots using a buffer distance of 1500,m. We used logistic and linear regression analyses to determine the community and landscape factors that best explain L. maackii presence and density. We also tested whether woodlot invasion by L. maackii begins at woodlot edges. Presence of L. maackii was significantly explained only by distance from the nearest town (logistic regression, p=0.017); woodlots nearer town were more likely to be invaded. Among invaded woodlots, density of L. maackii was positively related to the amount of edge in the landscape (partial R2=0.592) and negatively related to total tree basal area (partial R2=0.134), number of native woody species (partial R2=0.054), and sapling shade tolerance index (partial R2=0.054). Lonicera maackii in woodlot interiors were not younger than those on the perimeters, leading us to reject the edge-first colonization model of invasion. Our findings reveal that landscape structure is of primary importance and community features of secondary importance in the invasion of L. maackii. This shrub is invading from multiple foci (towns) rather than an advancing front. Connectivity in the landscape (i.e. the number of corridors) did not promote invasion. However, edge habitat was important for invasion, probably due to increased propagule pressure. The community features associated with L. maackii invasion may be indicators of past disturbance. [source] Ethnicity and other factors that may affect the prevalence of echogenic intracardiac foci in the fetusJOURNAL OF CLINICAL ULTRASOUND, Issue 7 2006Louis Lim MD Abstract Purpose. To study ethnicity and other possible factors that may affect the incidence of echogenic intracardiac foci (EIF) when detected via sonographic examination. Materials and Methods. Patients were referred to our institution for sonographic evaluation from a wide range of practice formats, including both private obstetric practices as well as community outpatient clinics. The study protocol included presence or absence of EIF, maternal age, ethnicity, gestational age during the examination, optimal versus suboptimal scans, presence of other fetal malformations and sonographic markers, and presence of chromosomal anomalies. Fetal outcome was ascertained in 90% of the study group. For statistical analysis, the chi-square test and the Student t -test were used. Results. The study group included 1,543 patients who had a fetal anatomy survey between 16 and 24 weeks' gestation. The prevalence of EIF was similar in all 4 ethnic groups (Asian, Hispanic, black, and white). There were 76 cases of EIF,an overall prevalence of 4.9%. Seventy-one of these cases were isolated in the left ventricle, 2 were isolated in the right ventricle, and 3 showed multiple foci. The prevalence of EIF was similar between younger and older patients, early and late gestational age at the time of sonographic examination, and optimal and suboptimal sonograms. Fetuses with EIF had significantly more congenital anomalies and other sonographic markers compared with fetuses without EIF. Conclusions. We did not find any significant difference in the prevalence of EIF among the 4 different ethnic groups. The association between congenital anomalies and other sonographic markers should be studied further. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:327,329, 2006 [source] Non-pustular palmoplantar psoriasis: is histologic differentiation from eczematous dermatitis possible?JOURNAL OF CUTANEOUS PATHOLOGY, Issue 2 2008Ovgu Aydin Both palmoplantar psoriasis and eczematous dermatitis of this skin area share similar histologic features. The punch biopsies from 17 patients with psoriasis and 25 with eczematous dermatitis were evaluated, blind to the clinical diagnosis. Vertically situated multiple foci of parakeratosis, alternating with orthokeratosis, were the only statistically significant feature in the differential diagnosis of palmoplantar psoriasis [76.5% (13/17), p = 0.005]. In contrast, multiple foci of parakeratosis [70.6% (12/17)], loss of granular layer at least in focal areas [41.2% (7/17)], presence of neutrophils at the summits of parakeratosis [4% (1/17)], presence of neutrophils and/or plasma in the parakeratotoic foci [94.1% (16/17) and 11.8% (2/17)], psoriasiform epidermal hyperplasia [88.2% (15/17)], spongiosis restricted to the lower parts of the epidermis [47.1% (8/17)], dyskeratotic cells [82.4% (14/17)], thinning of suprapapillary plate [58.8% (10/17)], edema of the papillary dermis [29.4% (5/17)], presence of tortous and dilated capillaries in the papillary dermis [52.9% (9/17) and 76.5% (13/17)] and extravasated erythrocytes [29.4% (5/17)] were found to be more common in palmoplantar psoriasis compared with eczematous dermatitis; but none of them was statistically significant. Interestingly, spongiotic vesicles were seen in most of the patients with psoriasis [76.5% (13/17)]. In conclusion, according to our findings, many features of palmoplantar psoriasis overlapped with those of eczematous dermatitis. However, detection of multiple parakeratotic foci, placed vertically, alternating with orthohyperkeratosis, could be considered in favor of palmoplantar psoriasis. [source] Pulmonary capillary hemangiomatosis incidentally detected in a lobectomy specimen for a metastatic colon cancerPATHOLOGY INTERNATIONAL, Issue 6 2006Suzuko Moritani Pulmonary capillary hemangiomatosis is a rare vascular proliferative disease of unknown etiology. The common clinical features are slowly progressive and finally fatal pulmonary hypertension. The clinical diagnosis is usually difficult. Because most reported cases are of autopsy, little is known about its incipient lesion and natural history. Presented herein is a case of pulmonary capillary hemangiomatosis incidentally detected in a surgically resected lung for a metastatic colon cancer. The patient was a 60-year-old Japanese woman with a history of sigmoid colon cancer 3 years previously. The patient had undergone a right lower lobectomy for a metastatic tumor in the hilar region and a thoracoscopic tumorectomy of the peripheral area of the left upper lobe. Except for an episode of hemoptysis 2 weeks prior to the lung surgery, there were no other clinical symptoms characteristic of pulmonary capillary hemangiomatosis. The non-tumor area of right lower lobe showed multiple foci of capillary proliferation affecting alveolar walls, interlobular septa and pleura associated with patchy hemorrhage. There was a minor degree of vascular and bronchial involvement by capillary proliferation. It is suggested this particular case is an incidentally detected clinically incipient stage of pulmonary capillary hemangiomatosis. Passive congestion secondary to metastatic colon cancer in the hilar region may have contributed to the pathogenesis of this lesion. [source] Pigmented neurofibroma: Report of two cases and literature reviewPATHOLOGY INTERNATIONAL, Issue 7 2001Mayumi Inaba Two cases of pigmented neurofibroma of the skin are reported. In case 1, the tumor was removed from the back of a 55-year-old man with no associated neurofibromatosis. In case 2, the tumor was removed from the abdominal wall of a 21-year-old woman with neurofibromatosis. Both tumors consisted of benign, short spindle cells and multiple foci of scattered melanin-laden cells. In case 1, the spindle cells were arranged in a storiform pattern, resembling features of dermatofibrosarcoma protuberans. Immunohistochemically, the spindle cells of both cases were demonstrated to be positive for S-100 protein and CD34. The melanin-laden cells stained positively for HMB-45. This report describes an additional two cases of pigmented neurofibroma that conform to the new diagnostic criteria for this disease. [source] Brief communication: Histology and micro CT as methods for assessment of facial suture patencyAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2009Lauren E. Reinholt Abstract The extent of fusion in facial sutures has implications for topics ranging from biomechanics to phylogeny reconstruction. An unfortunate limitation of studying sutural fusion in skeletal specimens is that it is difficult to assess whether apparently patent sutures are in fact fused internally. Both histology and microcomputed tomography (CT) are potential tools for solving this, but relatively few studies have attempted to discern the limits of micro CT for visualization of microanatomical structures. We examined microanatomical aspects of facial sutures in adult cadaveric samples from captive bushbabies. Premaxillary and nasopremaxillary sutures were examined in serially sectioned snouts of four greater bushbabies (Otolemur garnettii) and four lesser bushbabies (Galago moholi). Sections containing sutures with osseous bridging were rated as "fused," and the presence or absence of grooves on the external side was recorded. One bushbaby was studied using micro CT prior to physical sectioning. O. garnettii and two of the G. moholi show multiple foci of fusion. Histological examination confirmed that sutural fusion is limited to the internal surface in numerous sections, resulting in an external notch. Such points of internal fusion could be clearly visualized in raw CT slices. The presence of such notches suggests that external examination can underestimate the degree of suture fusion. Thus, microanatomical evidence may be needed to fully assess biomechanical correlates and phylogenetic interpretations based on fusion of facial sutures. Our results also indicate micro CT may be a useful tool to obtain this evidence. Am J Phys Anthropol 2009. © 2009 Wiley-Liss, Inc. [source] Synchronous bilateral multifocal canalicular adenoma: a case report of an unusual findingCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 8 2009G. Mansueto Summary Canalicular adenoma is a benign neoplasm of the minor salivary glands. The most common site is the upper lip, and the adenoma usually appears as a single lesion. Few cases of multiple foci of canalicular adenoma (CA) have been reported in literature. We report a case of a 78-year-old woman with CA of the nasolabial wrinkle on both sides of the nose, which occurred at the same time. The lesions recurred after about 1 year. This report adds to the literature another case of multiple, bilateral CA with synchronous occurrence. [source] | |||||||||||||