共查询到20条相似文献,搜索用时 15 毫秒
1.
NJ Unakar WF Bobrowski JY Tsui M Bagchi CV Harding 《Canadian Metallurgical Quarterly》1993,12(7):675-683
Alterations in elemental composition of the normal lens have been reported to accompany galactose cataract development in rats. In this report we present the changes in regional distribution of Na, K, Cl, P, S and Ca during the reversal of galactose-induced cataracts. Elemental X-ray maps of lenses from young female Sprague Dawley rats fed 50% galactose for 20 days were examined at 0, 20, 40 and 90 days following the transfer of galactose fed rats to Purina Rat Chow diet. Reinstatement of normal elemental distribution accompanied the progression of lens transparency. By 90 days on the rat chow diet, K had increased and Na, Cl and Ca had decreased so that a near normal lenticular distribution of these elements was established. The reinstatement of elemental distribution during cataract reversal followed a pattern similar to that observed for alterations during cataract development, initiating near the equatorial surface and expanding centrally. The correlation between the alterations in the distribution of the elements studied and our previously reported morphological investigation of lenses during galactose cataract reversal is discussed in this report. 相似文献
2.
3.
N Ibaraki LR Lin L Dang VN Reddy DP Singh T Sueno LT Chylack T Shinohara 《Canadian Metallurgical Quarterly》1997,64(2):229-238
Although the motivation to quit using substances is an important prognostic and treatment-matching factor in substance abuse treatment, there is limited information on motivation to quit among individuals with schizophrenia. This study used the five-stages-of-change model to evaluate the motivational levels of 497 individuals with schizophrenia or schizoaffective disorder in an outpatient mental health clinic. Rates of substance abuse, motivation levels to quit each specific substance, and correlates to motivational levels were evaluated. At least one substance use disorder was diagnosed in 224 of the subjects (45%); however, there was significant variability among the caseloads of the outpatient division teams. The patients in the triage/acute services and community outreach teams had substance abuse rates of about 70 percent. Most subjects had low motivation to quit substances, and the rates varied according to substance (range of 41% for opiates to 60% for cocaine). Treatment-matching strategies are suggested in the motivation-based treatment model. 相似文献
4.
DE Holt TA Ryder A Fairbairn R Hurley D Harvey 《Canadian Metallurgical Quarterly》1997,16(10):570-576
1 Chloramphenicol is used extensively in non-industrialized countries for the treatment of life-threatening infections because it is cheap and effective, despite its known hemotoxicity and linkage to fatal aplastic anaemia. It is important to define the mechanism of toxicity so that means can be devised to ameliorate the toxic effects in order to produce safer usage. 2 Chloramphenicol, at concentrations from 5 mM to 2 mM initiated apoptosis in dividing cells from a monkey kidney-derived cell line and in haematopoietic progenitor cells from human neonatal cord blood. 3 Growth of progenitor cells was suppressed at concentrations of chloramphenicol which would be considered less than therapeutic during patient treatment. 4 These effects could be ameliorated in progenitor cells by co-culture with the antioxidant mercaptoethylamine and in monkey kidney cells by co-culture with vitamin C. 5 This is the first report of apoptosis in chloramphenicol toxicity and suggests a possible link between a metabolic event i.e. the production of free radicals; a morphological effect, apoptosis; and a clinical effect, bone marrow suppression and aplastic anaemia. 相似文献
5.
PURPOSE: To evaluate the importance of lens epithelial cell death in age-related cataract. To determine whether the large percentage of terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL)-positive lens epithelial cells previously reported in human capsulotomy specimens results from apoptosis or necrosis. METHODS: Capsulotomy specimens from patients who had undergone cataract surgery and epithelia from cataractous lenses of eye bank eyes were compared with epithelia from noncataractous lenses of eye bank eyes. DNA fragmentation was assayed using the TUNEL method. Cell membrane integrity was tested using a fluorescent stain for DNA, BOBO-3, that is excluded from living cells. Cell proliferation was assayed by labeling with 5-bromo-2'-deoxyuridine (BrdU). The number of cells in different regions of the lens epithelium was measured by digital imaging and computerized counting of nuclei after staining with methyl green. RESULTS: TUNEL-positive cells were sometimes detected adjacent to denuded regions of capsulotomy specimens, especially when epithelia were not fixed immediately after surgery. TUNEL-stained cells usually stained with BOBO-3, indicating loss of plasma membrane integrity. No BrdU-labeled cells were detected in capsulotomy specimens. Cell density in cataractous lens epithelia was similar to that in normal lens epithelia. In cataractous lenses from eye bank eyes, cell density in the region of the epithelium overlying the cataract was higher than cell density in the region of the epithelium overlying the transparent part of the lens. No correlation was found between cell density and cataract severity or between cell density and age. CONCLUSIONS: TUNEL staining of lens epithelial cells in capsulotomy specimens most likely results from necrotic cell death caused by damage during or soon after cataract surgery. Loss of cells from the lens epithelium, by apoptosis or other mechanisms of cell death, does not seem to play a major role in age-related cataract formation. 相似文献
6.
The lens epithelium of the human eye plays a crucial role in the pathogenesis of primary and secondary cataract. Sixty hematoxylin-eosinstained lens epithelia were examined using a light microscope. Cell parameters were compared to one another in the various age groups of patients, between patients with secondary cataract (radiation cataract, steroid cataract and traumatic cataract) and patients with senile cataract, and between male and female patients. The t-test was used for statistical comparison. The median cell density was 3116.5 cells/mm2. The median nucleus-plasma ratio was 1:2.74. Patients with secondary cataract had a larger medium cell and nucleus area as well as a higher nucleus-plasma ratio and a lower cell density than patients with senile cataract. A part from degenerative and proliferative cell changes we found various cell types. The age of patients and the cause of cataract correlate with morphometric changes of lens epithelium cells. However, there was no correlation between specific cytologic changes and causes of cataract. 相似文献
7.
8.
PURPOSE: To report results of secondary intraocular lens implantation after cataract surgery in children. METHODS: We reviewed clinical records for a 5-year period of patients who had cataract surgery in childhood and received a secondary intraocular lens implant. We studied indications for secondary intraocular lens placement; surgical procedures for intraocular lens implantation; preoperative and postoperative visual acuity, refractive error, and binocular status; and complications of the procedure. RESULTS: A secondary intraocular lens was placed in 28 eyes of 25 patients who had cataract surgery in childhood. In 20 eyes, the lenses were placed in the ciliary sulcus. The other eight eyes had insufficient capsular support for an intraocular lens; in two, the intraocular lens was placed in the anterior chamber and, in six, in the posterior chamber with suture fixation to the sclera. Twenty of 28 eyes (71%) had measurable improvement in visual acuity; only one eye had a decrease in visual acuity of 2 lines. Fifteen patients (54%) had a final refraction within 1.50 diopters of the fellow eye; 21 (75%) were within 3.00 diopters. During follow-up, two eyes developed glaucoma. One had transient pressure elevation; one required two filtration procedures. Three patients required Nd:YAG capsulotomy. Six patients demonstrated Worth fusion at distance and near; three demonstrated 200 seconds of arc or better stereo visual acuity. CONCLUSION: Secondary placement of an intraocular lens in the posterior chamber appears to be a safe, effective alternative for correction of aphakia in the contact lens- or spectacles-intolerant child or young adult. 相似文献
9.
In vitro studies of chemical mutagens and carcinogens. I. Stability studies in cell culture medium 总被引:2,自引:0,他引:2
A quantitative microbial assay was used to study the stability of known mutagenic and carcinogenic compounds in cell culture medium. Ten direct-acting carcinogens, when incubated in culture medium with 15% fetal bovine serum at pH 7.2-7.4 and 37 degrees C, became inactive at varying rates. Biologic half-lives of the test compounds ranged from 8 minutes to 67 hours. In contrast, six procarcinogens showed no significant inactivation after 3 weeks' incubation. The biologic half-lives of each compound were presented, and the significance of these findings as they relate to cell culture carcinogenesis and mutagenesis assays was discussed. 相似文献
10.
In this paper we estimate the size of several categories of "Israeli" immigrants in the United States. According to the 1990 U.S. census, there were about 95,000 Israeli-born immigrants in the United States in that year. Using the language and ancestry information available in the Public Use Microdata Sample (PUMS) of the 1990 census, we estimate that of this total, about 80,000 are Jews and 15,000 are Palestinian Arabs born in Israel. In addition to the Israeli-born, we present a range for the number of Jewish immigrants from Israel who are not Israeli-born (about 30,000-56,000). Thus our estimate for the total number of Jewish immigrants from Israel in the United States in 1990 is between 110,000 and 135,000. Fertility information available in the PUMS, also enable us to provide estimates for the number of second-generation Israelis in the United States in the 1990 (about 42,000). Finally, using both the 1980 and 1990 PUMS, we provide estimates for the rate of return migration among Israeli-born Jewish immigrants in the United States. 相似文献
11.
TR Shearer H Ma M Shih I Hata C Fukiage Y Nakamura M Azuma 《Canadian Metallurgical Quarterly》1998,17(11):1037-1043
PURPOSE: To measure changes in levels of Lp82 during maturation and selenite cataract formation in rat lens. Lp82 is a lens-specific, calcium-activated isozyme from the calpain family of cysteine proteases (EC 34.22.17). METHODS: Competitive RT-PCR was used to assess Lp82 and m-calpain mRNA concentrations. Immunoblotting and ELISA after DEAE chromatography measured Lp82 and m-calpain protein levels. Casein zymography assessed proteolytic activities in regions and whole lenses from maturing rats. RESULTS: Levels of Lp82 mRNA, protein, and caseinolytic activity decreased more rapidly during maturation of rat lens than for m-calpain. Unexpectedly, the water-insoluble fraction of rat lens contained enzymatically active Lp82. Selenite injection also caused major loss of Lp82 protein during cataract formation. CONCLUSIONS: Lp82 is a proteolytic enzyme likely functioning in early lens development and maturation. The rapid loss of Lp82 activity during lens maturation is probably caused by three factors: autodegradation associated with the proteolysis of soluble and insoluble proteins occurring in the rat lens nucleus, association of Lp82 with the lens insoluble fraction, and loss of Lp82 mRNA. Lp82 may function early in lens maturation along with m-calpain, which then is predominant in the latter stages of maturation. Proteolysis in selenite cataract is partially caused by over-activation of Lp82. 相似文献
12.
O Leoni R Iori S Palmieri E Esposito E Menegatti R Cortesi C Nastruzzi 《Canadian Metallurgical Quarterly》1997,5(9):1799-1806
Epidemiological and pharmacological studies have shown that colorectal cancer development could be reduced by consuming vegetables that contain glucosinolates. In view of this the effect of some glucosinolates and their isothiocyanate (ITC)-derived products on in vitro cell growth was studied. We report the isolation and characterization of ITCs derived from glucosinolates by using HPLC, GC-MS, and NMR techniques. The in vitro activity of ITCs on human erythroleukemic K562 cells has been investigated by using two alternative approaches: the in situ and pre-mix methods. No differences in antiproliferative activity were found comparing the effect of ITCs produced either of these methods. In the experimental conditions used, the production of ITCs from glucosinolates is almost quantitative as confirmed by HPLC or GC-MS analysis. The ITCs' inhibitory activity on K562 cells growth is particularly evident in the cases of ITCs derived from sinigrin, progoitrin, epi-progoitrin, glucotropaeolin and glucocheirolin. Finally, the antiproliferative activity of the ITCs obtained from glucoraphenin, taken as an example, was determined on other tumor cell lines with a different origin and hystotype. Considering the antiproliferative activity found for ITCs these compounds could be considered potentially responsible for the reduction of colorectal cancer associated with diets rich in cruciferous vegetables. Further studies will be aimed at the possible application of glucosinolate-derived products as chemopreventive cancer agents. 相似文献
13.
HV Gimbel 《Canadian Metallurgical Quarterly》1996,103(11):1871-1875
To study brain regions involved in familiarity discrimination, rats were shown sets of novel and familiar objects. On each trial two objects were shown simultaneously to a rat so that one eye saw a novel object while the other saw a familiar object. Thus novel and familiar objects were seen with the same conditions of alertness and eye movements. Activated neurones were revealed by staining for products of the immediate early gene c-fos. Familiar stimuli activated significantly fewer neurones than novel stimuli in perirhinal cortex and area TE of temporal cortex, and the ventral lateral geniculate nucleus of the thalamus, but not in the hippocampus or other areas sampled. These findings are discussed in relation to recognition memory. 相似文献
14.
MM Krasnov AA Kasparov IA Mustaev AS Vvedenski? Iu Naim 《Canadian Metallurgical Quarterly》1998,114(4):8-10
Sixty-seven patients with cataracts of different degree of maturity were operated on using phacoemulsification with implantation of soft IOLs through a dot self-hermetized incision. The advantages of this method over interventions with a large incision are a shorter postoperative rehabilitation (2-3 weeks), no postoperative astigmatism, low traumatism, and a lower risk of pre- and postoperative complications. Insertion of soft IOLs with injectors permits intraocular correction of vision through a dot incision used in phacoemulsification; no sutures are needed, and hospital stay is decreased to just 1-2 days. 相似文献
15.
ME Limoncu IC Balcio?lu K Yereli Y Ozbel A Ozbilgin 《Canadian Metallurgical Quarterly》1997,35(9):2430-2431
A new liquid culture medium prepared with chemicals that can be obtained economically and commercially was tested in in vitro cultivation of Leishmania promastigotes to obtain a large number of organisms to use in serological studies. The number of Leishmania infantum and Leishmania tropica promastigotes taken from Novy-MacNeal-Nicolle (NNN) medium reached 1 x 10(7)/ml at the end of the 8th day in our new medium, though in NNN medium the number of organisms reached only 5 x 10(6)/ml. After 10 subsequent passages, the culture medium prepared was evaluated as being quite inexpensive, simple, and successful compared with other commercially available liquid culture media. 相似文献
16.
BACKGROUND: When trabeculectomy and cataract extraction with intraocular lens insertion are combined, do the success and complication rates add. MATERIAL AND METHODS: Follow-up of 47 eyes of 34 patients with combined trabeculectomy and cataract extraction with intraocular lens implantation after 12 to 42 months. RESULTS: With a low perioperative complication rate the intraocular pressure after one year was below 22 mm Hg in 90% without any medication and in 98% additional glaucoma therapy. After 2 and 3 years the intraocular pressure was normal without any additional therapy in 83% of the eyes. The visual acuity was better or equal to the preoperative value in 89% of the cases. CONCLUSIONS: The combination of trabeculectomy and of cataract extraction with intraocular lens implantation has a low complication rate and gives good results regarding intraocular pressure and visual rehabilitation. When a trabeculectomy is indicated, the indication for a simultaneous cataract extraction with intraocular lens implantation should not be to restricted. 相似文献
17.
18.
The present study tested the assertion that there exists exclusively in persons with senile cataracts a serum factor capable of precipitating with gamma crystallin extract from bovine lens. The results of this work do not support this assertion without the imposition of rigid specifications regarding test solution concentrations and observation time. Among the 84 subjects tested, 2 individuals had posterior subcapsular cataracts. The precipitates resulting from incubation with serum from these individuals were similar to those resulting from incubations with serum from senile cataract patients. The present study did not confirm the existence of exclusive serum factors capable of precipitating with gamma crystallin extract in patients with senile cataracts. 相似文献
19.
A Beyer-Mears FP Diecke K Mistry C Ellison E Cruz 《Canadian Metallurgical Quarterly》1997,55(2):78-86
Attitudes toward deviant behavior that might indicate psychiatric disorder were investigated among the Inuit of Northern Québec (Nunavik). In a convenience sample of 137 Inuit adults, respondents were randomly presented with one of six different vignettes that described a man with "strange" behavior who was either threatening or withdrawn and whose problem was labeled either "isumaluttuq" ("burdened or weighed down by thoughts"), "demon possession," or "mental illness." Respondents rated their willingness to live, work, or hunt with this person and allow him into their family on a social distance scale. Significant predictors of greater social distance were female gender, more education, less familiarity with the behavior, and perception of the person as less likely to recover. There were no significant effects of vignette behavior or label on social distance ratings. Rating of likelihood of recovery was influenced by the vignette label, with isumaluttuq associated with less chance of recovery. Ascribing strange behavior to morally wrong action and to spirits or demons were highly inter-correlated and each was associated with perception of greater likelihood of recovery. Results suggest that Inuit attitudes toward deviant behavior are influenced more by perceived familiarity and likelihood of recovery than by labels, causal attributions, or explanations. The indigenous psychological concept of isumaluttuq does not serve to reduce social stigma. Efforts to promote the community integration of psychiatric patients through education should aim to increase familiarity with the problematic behavior and emphasize potential for recovery. 相似文献
20.
R Shern-Brewer N Santanam C Wetzstein J White-Welkley S Parthasarathy 《Canadian Metallurgical Quarterly》1998,18(7):1181-1187
The oxidation of low density lipoprotein (LDL) has been suggested as a key event in atherogenesis. Paradoxically, exercise, which imposes an oxidative stress, is an important deterrent of cardiovascular disease. In study 1 the oxidizability of LDL was enhanced in exercisers compared with sedentary controls. The lag time of isolated LDL subjected to copper-induced in vitro oxidation was significantly shortened in the exercisers compared with sedentary subjects. This increased sensitivity was not due to a decreased presence of vitamin E. Instead, these findings suggested that the LDL of exercisers may contain increased amounts of preformed lipid peroxides, which account for the increased oxidizability. In study 2, a group x sex ANOVA revealed that male exercisers had a significantly longer mean lag time than male sedentary subjects and that females had similar mean lag times regardless of exercise group. This remained the case when statistical adjustment was made for age, body mass index, blood lipid levels, LDL, and plasma alpha-tocopherol levels. Study 1 exercisers had been in training for a shorter time (< 1 year) than study 2 exercisers (> 2 years). These findings suggest that truly "chronic" exercise (aerobic intensity over several months) decreases the susceptibility of a male exerciser's LDL to undergo oxidation. Conversely, regular aerobic stress during an overall shorter time span creates a more oxidative environment in the body, thus increasing the susceptibility of LDL to undergo oxidation. The oxidative stress of aerobic exercise does not appear to adversely affect the oxidizability of LDL in women. 相似文献