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101.
A patient homozygous for the SCA6 gene with retinitis pigmentosa 总被引:1,自引:0,他引:1
The present authors studied a 55-year-old-patient homozygous for the SCA6 gene who experienced frequent attacks of positional vertigo at 37 years of age with subsequent staggering gait and night blindness. Retinitis pigmentosa (RP), as well as cerebellar ataxia and vertical antidirectional nystagmus, were detected. The subject's parents were first cousins, and two of his three male cousins, whose parents were also first cousins, had RP without ataxia or nystagmus. The numbers of CAG repeats in the expanded alleles of the SCA6 gene found by molecular analysis were 21 and 21. The genetic results were negative for SCA1, SCA2, SCA3, SCA7 and dentatorubral pallidoluysian atrophy. The retinal degeneration in this patient is most likely to be secondary to a genetic disorder of autosomal or X-linked recessive inheritance rather than SCA6. Other reported cases of patients homozygous for the SCA6 gene are also reviewed. 相似文献
102.
Takaaki Hayashi Katsuhiro Hosono Akiko Kubo Kentaro Kurata Satoshi Katagiri Kei Mizobuchi Minehiro Kurai Norihito Mamiya Mineo Kondo Toshiaki Tachibana Hirotomo Saitsu Tsutomu Ogata Tadashi Nakano Yoshihiro Hotta 《American journal of medical genetics. Part A》2020,182(6):1500-1505
Mucolipidosis type IV (MLIV) is an autosomal recessively inherited lysosomal storage disorder characterized by progressive psychomotor delay and retinal degeneration that is associated with biallelic variants in the MCOLN1 gene. The gene, which is expressed in late endosomes and lysosomes of various tissue cells, encodes the transient receptor potential channel mucolipin 1 consisting of six transmembrane domains. Here, we described 14‐year follow‐up observation of a 4‐year‐old Japanese male MLIV patient with a novel homozygous in‐frame deletion variant p.(F313del), which was identified by whole‐exome sequencing analysis. Neurological examination revealed progressive psychomotor delay, and atrophy of the corpus callosum and cerebellum was observed on brain magnetic resonance images. Ophthalmologically, corneal clouding has remained unchanged during the follow‐up period, whereas optic nerve pallor and retinal degenerative changes exhibited progressive disease courses. Light‐adapted electroretinography was non‐recordable. Transmission electron microscopy of granulocytes revealed characteristic concentric multiple lamellar structures and an electron‐dense inclusion in lysosomes. The in‐frame deletion variant was located within the second transmembrane domain, which is of putative functional importance for channel properties. 相似文献
103.
The studies described here examine the involvement of the fibrinolytic cascade and its endogenous inhibitors in the regulation of activity of matrix metalloproteinases and cartilage degradation related to non-inflammatory joint disease, like osteoarthritis. An interleukin-1-induced model of degradation using [35S]-labeled bovine and human articular cartilage explants was utilized. One goal of these studies was to compare the responses of bovine and human articular cartilage. Degradation was not inhibited by
1-PI, PAI-1,
2-macroglobulin,
2-antiplasmin or TIMP-2, when IL-1 alone was added. Addition of human plasminogen to bovine explants, at concentrations found in human synovial fluid, increased degradation by three to fourfold. Under these conditions, the degradation was inhibited effectively by all of the endogenous inhibitors tested, indicating the presence of a cascade where activated chondrocytes are a source of u-PA. Plasminogen activated by u-PA gives plasmin, which is known to further activate pro-stromelysin. Stromelysin is essential for activation of collegenase. Not only TIMP, but also inhibitors at earlier steps of activation like PAI-1,
2-antiplasmin,
1-PI and
2-macroglobulin inhibited degradation, and could provide cartilage protection in vivo. An experiment with human articular cartilage explants showed that very little or no degradation occurred when human articular cartilage explants were stimulated with interleukin-1 alone. Addition of human plasminogen (at physiologically relevant concentrations) resulted in significant degradation, which was inhibited in the same manner as in bovine explants, by inhibitors of the fibrinolytic cascade and TIMP. TIMP is much more efficient in human explants, indicating the limited participation of human plasmin in the degradation of human cartilage. Although speculative, it is possible that in vivo, cartilage degradation could be promoted not only by TIMP/MMP imbalance, but also accelerated by decreased levels of certain serpins in synovial fluid (e.g. PAIs,
2-antiplasmin and
1-PI).accepted by W. B. van den BergWork supported by OsteoArthritis Science Inc., One Kendall Square, Bldg. 200, Cambridge, MA 01139, USA. 相似文献
104.
Aluminum chloride induced neurofibrillary degeneration may provide a useful model for the study of a human dementia process. This possibility was assessed in cats trained to perform on a delayed-response task, a conditioned avoidance task, visual and temporal discrimination tasks and a motivational task involving rewarding intracranial electrical stimulation. After an initial asymptomatic period short term retention and acquisition of a conditioned avoidance response were selectively impaired. The associated ultrastructural abnormalities plausibly implicate the cytoplasmic streaming mechanism in the cellular substrate for some retention and acquisition phenomena. 相似文献
105.
Markers of cartilage degradation hold a great, but so far underutilized potential in the research and clinical management of joint diseases such as osteoarthritis (OA) and rheumatoid arthritis (RA). With the rapid pace of development of such markers, they are likely to emerge as promising clinical tools for several uses. These roles may include: improving preclinical and clinical development in arthritis research; differentiation of patients with high and low turnover states at disease diagnosis; selection of optimal therapy and therapy dose for the individual patient; monitoring disease progression; and predicting disease outcome.This review focuses on the cartilage matrix components and the metabolites from this very special tissue that have been proposed as biochemical markers. Special attention is focused on the challenges facing the development of such markers to the standards required for widespread practical use. Examples are provided on the current use of cartilage derived biochemical markers and perspectives for the future use of markers and required clinical documentation are presented. 相似文献
106.
Masugi Y Kameyama K Aiba M Mukai M Hara S Ohigashi T Murai M 《Pathology international》2003,53(4):241-245
We report a case of non-functional adrenocortical adenoma of 5.5 x 5.5 x 3.2 cm in size that had an unusual histopathological appearance in two respects. First, the tumor contained small adipose foci with osteogenesis and was suspected of being a myelolipoma based on its appearance on computerized tomography (CT) and magnetic resonance imaging. However, pathologically, the fat element was seen focally and was not accompanied by hematopoietic cells, and the diagnosis of myelolipoma was abandoned. Second, the tumor was suspected of being an adrenal carcinoma based on its appearance on CT scans and showed extensive degeneration: fibrosis, hemorrhage, loss of parenchyma and moderate atypism of the tumor cells. However, as the architecture of the tumor cells was non-diffuse and there were no necrotic foci or mitoses, and vascular or capsular invasion were not present, the tumor was concluded to be an adrenocortical adenoma rather than a carcinoma. We diagnosed the tumor as a non-functional adrenocortical adenoma with extensive degeneration as the extensive areas of fibrosis were particularly remarkable. Furthermore, the extensive areas of degeneration might have been caused not only by an ischemic effect but also by low hormone levels. 相似文献
107.
The omega neurons (ON1s) are a mirror-symmetrical pair of identified prothoracic auditory interneurons of crickets which have been previously described as intraganglionic. Using intracellular techniques we stained ON1s of female Teleogryllus oceanicus and found that many ON1s have axons which project anteriorly out of the prothoracic ganglion. The ascending axon arises contralateral to the soma at the most anteriolateral bend of the bow-shaped process of an otherwise "archetypical" ON1 and travels up the neck connective in a ventral position just inside the connective tissue sheath. The occurrence of the ascending axon is age-dependent. Seventy-five percent of ON1s stained in late nymphal stages and in young adults had an ascending axon while only 30% of ON1s in older adults had an ascending axon. Evidence is presented to show that ON1s having ascending axons are developmental variants of the "archetypical" ON1 and do not represent a separate neuron type. The two morphological types of ON1s are not distinguishable on the basis of their responses to sound stimuli having carrier frequencies of 3.5-60 kHz. Although we know that the ascending axon conducts action potentials, its target and terminal morphology are not yet known. 相似文献
108.
B E Reese 《The Journal of comparative neurology》1986,250(1):8-32
The topographic organization of the uncrossed retinal projections to the dorsal lateral geniculate nucleus (dLGN) and superior colliculus (SC) was studied in normal adult hooded rats and in rats subjected to unilateral ocular enucleation on the day of birth. Sections were stained for anterograde degeneration products following discrete retinal lesions at various locations. The projection from the temporal crescent to the dLGN in neonatally enucleated rats had an expanded but topographically normal organization, with the nasotemporal and dorsoventral retinal axes displaying polarities identical to those in normal adults. Neonatal enucleation permits the remaining uncrossed retinogeniculate projection to extend primarily along the "lines of projection" into neuropil normally recipient of binocularly conjugate crossed projections. In the SC, the dorsoventral axis of the temporal crescent showed a normal polarity, but the nasotemporal axis failed to display any topographic organization. Retinal loci in the temporal crescent projected throughout the rostrocaudal extent of the ipsilateral SC. Retinal lesions placed outside the temporal crescent failed to produce any substantial degeneration in ipsilateral dLGN or SC. These topographically distinct effects in dLGN and SC following unilateral eye removal on the day of birth are discussed in the context of differing constraints upon axonal ingrowth and connectivity during early development, which may normally bring about the characteristically distinct features of retinogeniculate and retinocollicular organization. 相似文献
109.
L. Carenini G. Finocchiaro S. Di Donato A. Visciani S. Negri 《Journal of neurology》1984,231(1):34-37
Summary Electromyographic examination and studies of motor and sensory conduction velocities were performed in 11 patients with a presumptive diagnosis of olivopontocerebellar atrophy with autosomal dominant transmission. Peripheral nervous system involvement was shown in eight. In two patients with early onset of disease, electrophysiological alterations clearly pointed to severe axonal degeneration, whereas in six they were compatible with slight demyelination.
Zusammenfassung Bei elf Patienten, bei welchen eine olivopontocerebelläre Atrophie mit autosomal dominanter Übertragung angenommen wurde, führten wir eine elektromyographische Untersuchung und eine Bestimmung der motorischen und sensiblen Erregungsleitungsgeschwindigkeit durch. Bei acht dieser Patienten wurde eine Mitbeteiligung des peripheren Nervensystems nachgewiesen. In zwei Fällen mit frühem Krankheitsbeginn wiesen die elektrophysiologischen Veränderungen eindeutig auf eine schwere axonale Degeneration hin, während bei sechs die Befunde mit einer leichten Demyelinisation vereinbar waren.相似文献
110.
Alfredo García-Layana Sergio Recalde Maria Hernandez Maximino J. Abraldes Joo Nascimento Emiliano Hernndez-Galilea Begoa Olmedilla-Alonso Jose Juan Escobar-Barranco Miguel Angel Zapata Rufino Silva Mariana Caballero Arredondo María Carmen Lopez-Sabater Silvia Mendez-Martínez Nieves Pardias-Barn Pilar Calvo Patricia Fernndez-Robredo 《Nutrients》2021,13(4)
The purpose of this study is evaluate the efficacy and safety of medicinal products containing the original Age-Related Eye Disease group (AREDS) formulation at doses approved in Europe (EU, control group; n = 59) with a product that adds DHA, lutein, zeaxanthin, resveratrol and hydroxytyrosol to the formula (intervention group; n = 50). This was a multicenter, randomized, observer-blinded trial conducted in patients aged 50 years or older diagnosed with unilateral exudative Age related Macular Degeneration AMD. At month 12, the intervention did not have a significant differential effect on visual acuity compared with the control group, with an estimated treatment difference in Early Treatment Diabetic Retinopathy Study (ETDRS) of −1.63 (95% CI −0.83 to 4.09; p = 0.192). The intervention exhibited a significant and, in most cases, relevant effect in terms of a reduction in some inflammatory cytokines and a greater improvement in the fatty acid profile and serum lutein and zeaxantin concentration. In patients with unilateral wet AMD, the addition of lutein, zeaxanthin, resveratrol, hydroxytyrosol and DHA to the AREDS EU recommended doses in the short-term did not have a differential effect on visual acuity compared to a standard AREDS EU formula but, in addition to improving the fatty acid profile and increasing carotenoid serum levels, may provide a beneficial effect in improving the proinflammatory and proangiogenic profile of patients with AMD. 相似文献