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11.
BACKGROUND CONTEXT: Intramedullary fat-containing benign childhood tumors of the cord include lipomas, dermoid cysts, and teratomas. These are embryonal tumors. Most intramedullary fat-containing tumors are solitary. Multiple intramedullary lipomas are rare and may represent a spinal lipomatous malformation. The presence of another intramedullary dermoid tumor in the same case is rare. PURPOSE: The intent of this case report is to look at magnetic resonance features and possible mechanisms of association of these fat-containing intramedullary tumors. STUDY DESIGN/SETTING: A 3-year-old male child presented with spastic quadriplegia. METHODS: Magnetic resonance imaging (MRI) of spine was done on a 1.5-T scanner in different planes. RESULTS: MRI showed multiple intramedullary spinal lipomas with an intramedullary dermoid involving the conus, cord atrophy, and subarachnoid fat droplets. CONCLUSION: Multiple intramedullary lipomas with an intramedullary dermoid represent a form of spinal lipomatous malformation. Both may represent embryogenic mesenchymal inclusions and hamartomatous growth, which can be accurately diagnosed with MRI. 相似文献
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Deepak Gupta S. K. Vishwakarma 《Indian journal of otolaryngology and head and neck surgery》1989,41(1):6-8
Brain stem audiory evoked response (BAER) audiometry is a non-invasive and objective measure of a subject’s auditory function. The present paper attempts to establish normative data in Indian subjects. It was found that the BAER can detect asymptomatic high frequency hearing losses. Wave V’s threshold, latency and amplitude, along with comparisons between the auditory (subjective) and BAER threshold, are useful parameters in testing for organic and non-organic hearing disorders. 相似文献
14.
Mohan D Rao GR Swalsky PA Bakker A Martinez AJ Finkelstein SD 《Archives of pathology & laboratory medicine》2004,128(10):1161-1164
A 22-year-old man with previous radiation treatment for childhood astrocytoma underwent resection of a right parietooccipital lesion. Histopathology revealed a malignant neoplasm with areas of astrocytic and primitive neuroectodermal components. To resolve the relationship and cellular origin, representative tissue was microdissected from several targets, obtaining a balanced mixture of each element. Nonneoplastic brain parenchyma was separately microdissected to determine polymorphic marker informativeness and to serve as an internal negative control. Despite the relatively small quantity of tissue removed for each microdissection target, sufficient material was available for reliable, balanced, polymerase chain reaction-format genotyping encompassing a panel of tumor suppressor genes and genetic loci associated with these forms of neoplasia. The findings revealed distinct discordant genotypic profiles for each of the neoplastic components. The efficacy of the approach used for molecular analysis of this complex neoplasm and the implication of the genotypic findings are discussed. 相似文献
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Yeni YN Hou FJ Ciarelli T Vashishth D Fyhrie DP 《Annals of biomedical engineering》2003,31(6):726-732
Linear microcracks and diffuse damage (staining over a broad region) are two types of microscopic damage known to occur in vivo in human vertebral trabecular bone. These damage types might be associated with vertebral failure. Using microcomputed tomography and finite element analysis for specimens of cancellous bone, we estimated the stresses in the trabeculae of human vertebral tissue for inferosuperior loading. Microdamage was quantified histologically. The density of in vivo linear microcracks was, but the diffuse damage area was not, related to the estimates of von Mises stress distribution in the tissue. In vivo linear microcrack density increased with increasing coefficient of variation of the trabecular von Mises stress and with increasing average trabecular von Mises stress generated per superoinferior apparent axial stress. Nonlinear increase in linear crack density, similar to the increase of the coefficient of variation of trabecular shear stresses, with decreasing bone stiffness and bone volume fraction suggests that damage may accumulate rather rapidly in diseases associated with low bone density due to the dramatic increase of shear stresses in the tissue. © 2003 Biomedical Engineering Society.
PAC2003: 8719Rr, 8719Xx, 8759Ls, 8759Fm, 8710+e 相似文献
17.
Mohan D Rolston R Pal R Swalsky PA Sasatomi E Lee RE Finkelstein SD 《Human pathology》2004,35(4):482-487
The genetic diagnosis of Gaucher disease by molecular methods is complicated by the existence of a highly homologous transcribed pseudogene (96% identity) that is found in close proximity to the true gene on chromosome 1q21. In addition, the pseudogene sequence can mimic disease-causing mutations in the true gene. Selective polymerase chain reaction (PCR) amplification of the true gene can be accomplished in extracted DNA from fresh-frozen samples by designing oligonucleotide primers to hybridize to defined regions that are not present in the pseudogene. This standard molecular approach, which entails amplification of relatively long segments of intact DNA, is not feasible in archival, paraffin-embedded, solid-tissue specimens in which the negative effects of chemical fixation result in DNA strand scission and breakdown of nucleic acid. A novel approach, specifically created for use with archival, fixative-treated tissue specimens, was developed for detection and characterization of common mutations of Gaucher disease. Three separate robust PCR reactions were formulated, 2 for selective amplification of portions of only the true gene exons 2 and 9, with a third reaction targeting exon 10, wherein both the true and pseudogene were coamplified. In the latter, DNA sequencing was used to determine the presence of true and pseudogene allele content in addition to identification of base sequence alterations. This method, requiring a single, 4-microm-thick histologic section, was successfully applied to archival paraffin block tissue specimens that had been in storage for up to 75 years. It was capable of accurately genotyping common Gaucher disease mutations as well as discovering a novel mutation and genetic polymorphism. We recommend our approach when only fixative-treated tis sue is available for molecular genotyping. 相似文献
18.
Remodeling of the chromatin network plays an important role regulating embryonic development as well as differentiation. The SWI/SNF complex is an ATP-dependent chromatin-remodeling complex. It consists of several proteins, including an ATPase subunit, either Brg1 or Brm. Two subunits of this complex, Baf53a and Baf45, have been previously identified as being neural progenitor-specific. In this study, we show that Baf60c, another important part of this large complex, acts in a similar neural progenitor-specific manner. We show that during development Baf60c is expressed in neural progenitors in human retinas as well as mouse retina, cortex and spinal cord. Baf60c expression is lost during neural differentiation and its overexpression keeps the progenitors in a proliferative state through its interaction with the Notch pathway. Finally, we show that Baf60c is re-expressed in the Müller glial cells that re-enter the cell cycle after neurotoxic damage. 相似文献
19.
Summary Cyto- and myeloarchitectonic investigation of the temporal operculum and the exposed superior temporal gyrus was combined with a connection study of the projection fibers of the pertinent areas in the rhesus monkey.A belt-like organization of the auditory region with a koniocortex core (corresponding to AI) surrounded by belt areas was revealed. This organization principally resembled that of the auditory region of the cat (Rose and Woolsey, 1949; Woolsey, 1961) and that of other sensory regions (Sanides, 1972; Sanides and Krishnamurti, 1967). The belt is composed of one prokoniocortex area (proA, corresponding to AII) in parinsular location and of a caudal (paAc), lateral (paAlt) and rostral (paAr) parakoniocortex area. The latter has a particular character. It was found to be the target of thalamic projections of the caudalmost portion of GMpc. In contrast to the other parakonio areas it does not receive associations of the koniocortex.The belt areas, including the prokoniocortex, are ipsilaterally and transcallosally interconnected as in the somatic sensory (Jones and Powell, 1969a, b; Pandya and Kuypers, 1969; Pandya and Vignolo, 1969) and visual regions (Myers, 1962; Kuypers et al., 1965; Karol and Pandya, 1971).The koniocortex core is formed by two areas, Kam and Kalt, corresponding to the architectonic organization hitherto only known in man. The medial area (Kam) has a large number of homotopical callosal projections except at its medial border (to proA). The lateral area receives less callosal fibers, particularly most of its lateral portion is devoid of terminations. Since the belt areas are rich in callosal projections the supratemporal plane shows a pattern of three stripes of callosal terminations with two intermittent stripes void of terminations.While the projections of the koniocortex into the belt areas terminate prevalently in layer IV, the parakoniocortex sends fibers only into layers I and II of the koniocortex. This corresponds to results in somatic sensory (Pandya and McKenna, unpublished observations) and visual regions (Kuypers et al., 1965; Sanides and Vitzthum, 1965b; Spatz, personal communication).In contrast to other sensory regions the auditory koniocortex receives its exceptionally dense, homotopic callosal connections in the whole outer stratum with emphasis on layer III, as opposed to layer IV in the somatic sensory region. 相似文献
20.
Sarvdeep Singh Dhatt Vishal Kumar Deepak Neradi Praveen Sodavarapu Tensubam Tomthin Meetei Vijay Goni 《Indian Journal of Orthopaedics》2021,55(4):1046
AimsTo evaluate vitamin D3 levels in patients who presented with increased musculo-skeletal pain after release of lockdown period when compared to pre-lockdown status.IntroductionDuring this COVID pandemic, many countries have implemented lockdown measures and people have to work from home and many students and workers have to restrict themselves to home. During this period, their outdoor activities were limited. After the partial release of this lockdown many of them started to have some kind of physical activity and started experiencing body pains. We evaluated such patients for vitamin D3 levels and symptoms of fibromyalgia.MethodsThis is a retrospective analysis of patients from age group 18–60 presented to outpatient department or on telephonic consultation after partial release of lockdown. All patients who had mild back ache before lockdown and had symptoms exaggerated during this lockdown release were included. All patients were investigated for vitamin D3, PTH, thyroid profile, liver functional and kidney functional tests.ResultsOut of 120 patients presented to us in a period of 3 months, 31 patients had increased symptoms when compared to pre-lockdown status. 20 out of 31 patients had low vitamin D3 levels. 14 patients also developed symptoms of fibromyalgia.ConclusionThere might be many reasons for increased pain during lockdown, but we focussed specially only on vitamin D3 because of its association with increased symptoms of COVID-19. This is a gentle reminder to test for vitamin D3 levels and supplement if found deficient.Supplementary InformationThe online version contains supplementary material available at 10.1007/s43465-021-00376-8. 相似文献