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排序方式: 共有257条查询结果,搜索用时 15 毫秒
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E I Traboulsi J C Silva M T Geraghty I H Maumenee D Valle W R Green 《American journal of ophthalmology》1992,113(3):269-280
The eyes of a 22-month-old girl with the cobalamin C complementation type of combined methylmalonic aciduria and homocystinuria were studied with light and electron microscopy. We observed vacuolization of the iris pigment epithelium, loss of photoreceptors in the central 3.3 mm of the macula, partial loss of the nerve fiber and ganglion cell layers between the fovea and optic disk, and partial optic atrophy. The sclera in the posterior pole was thickened with deposition of mucopolysaccharide. Electron microscopy showed inclusions containing fine granular material in conjunctival fibrocytes; corneal epithelium, keratocytes, and endothelial cells; iris pigment epithelium; ganglion cells; retinal pigment epithelium; and choroid and scleral fibrocytes. Enlarged mitochondria and clear vacuoles distended the corneal endothelial cells. We found evidence of possible lysosomal dysfunction and mucopolysaccharide storage, as well as a clinicopathologic correlation of the macular degeneration in this disease. 相似文献
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W E Smiddy W J Stark E Young P E Klein W D Bias A E Maumenee 《Ophthalmic surgery》1986,17(10):644-649
Of 111 episodes of graft rejection in 66 patients, 62 responded to therapy with graft clearing (responders); 49 did not (non-responders). Both groups were of similar age, sex, and etiology; both had a similar rate of glaucoma and a similar rate of previous grafting. In responders the graft reaction was shorter in duration (2.2 vs. 5.6 wks. p less than 0.005), and it was necessary to increase the number of glaucoma medications more often in non-responders compared to responders (41% vs. 19%, p less than 0.02). The interval from surgery to reaction was similar in responders and non-responders (18.2 vs. 13.3 mos., p greater than 0.1). An epithelial rejection line was present in 11% of responders, but was not present in non-responders (p less than 0.05). Lymphocytotoxic antibody development correlated with rejection in 16 of 64 episodes. Patients who responded to treatment were more frequently asymptomatic (p less than 0.05) or were treated earlier following the onset of symptoms compared to non-responders (p less than 0.0001). 相似文献
5.
D P Zhu E P Economou S E Antonarakis I H Maumenee 《American journal of medical genetics》1992,42(2):173-179
Leber hereditary optic neuropathy (LHON) is a maternally inherited disorder characterized by bilateral acute or subacute loss of central vision, primarily in young males. A G----A single base mutation at 11778nt of the mitochondrial genome which eliminates a SfaNI restriction site [Wallace et al., 1988; Holt et al., 1989; Hotta et al., 1989; Singh et al., 1989; Vilkki et al., 1989; Yoneda et al., 1989; Stone et al., 1990; Lott et al., 1990.] has been found in more than 60% of the families with LHON studied. We studied 25 persons from 4 families with LHON using SfaNI and Mae III digestion of a 201 base pair polymerase chain reaction (PCR) product encompassing the 11778nt mutation. The loss of the SfaNI site and the acquisition of a Mae III site at 11778nt were identified in all maternal relatives of the LHON families studied. The mutation was heteroplasmic in all affected individuals, female carriers, and males at-risk. The heteroplasmy of mitochondrial DNA (mtDNA) was also identified by direct DNA sequencing of PCR amplified by direct DNA sequencing of PCR amplified mtDNA digested by SfaNI or Mae III. It appears that the proportion of the mutant mtDNA correlates with the severity of the disease. 相似文献
6.
Time course of hypo-osmotic swellings of human spermatozoa: evidence of ordered transition between swelling subtypes 总被引:2,自引:1,他引:2
Hossain AM; Rizk B; Barik S; Huff C; Thorneycroft IH 《Human reproduction (Oxford, England)》1998,13(6):1578-1583
The hypo-osmotic swelling test (HOST or HOS test) usually takes into
consideration the total HOS response value with no emphasis either on the
value of the response subtypes or the response evaluation time. This study
investigated the time course of HOS responses and analysed their
physiological relevance. Raw semen spermatozoa and Percoll washed
spermatozoa were used in the experiment. The morphological changes in the
sperm tail were monitored by incubating the spermatozoa in the hypo-
osmotic solution for 16 different time periods. The HOS reactive
spermatozoa and the type of HOS reaction (swelling subtypes) of the samples
subjected to different duration of treatment were identified under a phase
contrast microscope. Also the fate of individual spermatozoa in a
hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed
to a hypo-osmotic solution, the motility lasted usually less than 2 min and
motility characteristics were uniquely different from that of the
spermatozoa under iso-osmotic conditions. The HOS response development was
permanent but the motility loss due to hypo-osmotic shock was reversible up
to 1 min of incubation. There was an indication of ordered transition among
the HOS swelling subtypes apparently initiating with subtype b destined to
c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and
increase, respectively, while subtype b showed abrupt initial increase and
then gradual decrease. Transition from b to g could be direct or via one or
more than one subtypes. Ultrastructure based analysis indicated that HOS
response subtypes are the apparent reflection of the differences in the
cytoskeletal assembly of the sperm tail and thus may be identifying
different physiological variants in the sperm population. These results
indicate that shorter incubation is essential to document the kinetics of
various HOS responses but the conventional HOS test misses these important
HOS features because of lengthy incubation. Since the time course of
ordered transition of HOS responses will vary more than the total HOS
response in semen of different aetiologies, the importance of HOS response
subtypes and response evaluation time should be taken into consideration
when applying HOS test.
相似文献
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Baris O Delettre C Amati-Bonneau P Surget MO Charlin JF Catier A Derieux L Guyomard JL Dollfus H Jonveaux P Ayuso C Maumenee I Lorenz B Mohammed S Tourmen Y Bonneau D Malthièry Y Hamel C Reynier P 《Human mutation》2003,21(6):656-656
The OPA1 gene, encoding a dynamin-related GTPase that plays a role in mitochondrial biogenesis, is implicated in most cases of autosomal dominant optic atrophy (ADOA). Sixty-nine pathogenic OPA1 mutations have been reported so far. Most of these are truncating mutations located in the GTPase domain coding region (exons 8-16) and at the 3'-end (exons 27-28). We screened 44 patients with typical ADOA using PCR-sequencing. We also tested 20 sporadic cases of bilateral optic atrophy compatible with ADOA. Of the 18 OPA1 mutations found, 14 have never been previously reported. The novel mutations include one nonsense mutation, 3 missense mutations, 6 deletions, one insertion and 3 exon-skipping mutations. Two of these are de novo mutations, which were found in 2 patients with sporadic optic atrophy. The recurrent c.2708_2711delTTAG mutation was found in 2 patients with a severe congenital presentation of the disease. These results suggest that screening for OPA1 gene mutations may be useful for patients with optic atrophy who have no affected relatives, or when the presentation of the disease is atypical as in the case of early onset optic atrophy. 相似文献
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