[Study on alkaline hydrolysis of polyglutamate for de-esterification]

This paper reports the alkaline hydrolysis of poly(methyl glutamate), poly (benzyl glutamate) and copoly(methyl glutamate-benzyl glutamate-glutamic acid) for de-esterification. The results showed that in this process of alkaline hydrolysis the demethylation of poly(methyl glutamate) was faster, but debenzylation of poly(benzyl glutamate) was hardly processed. An increase in the methyl glutamate content of starting copolymers, in the alkaline concentration and the time of alkaline hydrolysis, and a decrease in the film thickness, would lead to a raise in the degree of alkaline hydrolysis, that is, an increase of the glutamic acid segment content in product of alkaline hydrolysis.

Ticlopidine-induced severe cholestatic hepatitis

We report a case study of an 86-year-old female patient with severe cholestatic hepatitis who was undergoing treatment with oral ticlopidine 250 mg daily for coronary artery disease. The patient had nausea and vomiting and was jaundiced after taking ticlopidine for 6 weeks. She was admitted to the hospital for further evaluation. Ultrasound and endoscopic retrograde cholangiopancreatography eliminated the presence of biliary obstruction. Results from a liver biopsy showed a histopathologic picture consistent with cholestatic hepatitis. Ticlopidine-induced cholestatic hepatitis has been reported 32 times in the foreign literature. This is the first reported severe cholestatic hepatitis (total bilirubin up to 43 mg/dl) case in Taiwan. Ticlopidine-related blood dyscrasia is a renowned adverse drug effect; liver function should be monitored in patients receiving ticlopidine therapy.

Increased nondisjunction of chromosome 21 with age in human peripheral lymphocytes

Fluorescence in situ hybridization (FISH) on binucleated cells with chromosome-specific DNA probes provides a convenient way to visualize reciprocal segregation patterns in daughter nuclei, and overcomes most problems related to the artefactual loss or gain of chromosomes that flaw chromosome preparations. In this study, FISH was employed to evaluate age- and sex-effects on spontaneous malsegregation, nondisjunction and loss of chromosome 21 in human lymphocytes after the first division in culture. A total of 68 healthy nonsmokers and nondrinkers of alcohol (37 males and 31 females) were grouped by age as Group I (0-10 years), Group II (20-30 years), Group III (40-50 years) and Group IV (60-70 years), with at least seven subjects per group and sex. FISH with a pericentric chromosome 21 specific DNA probe was carried out on binucleated lymphocytes, cytokinesis-blocked by cytochalasin B (6 microg/ml for 26 h) at 44 h after initiation of cultures. Linear regression analyses demonstrated a significant age-related increase in the frequency of micronuclei without chromosome 21 (MN-21)(r=0.73, p<0.001 in females; r=0.69, p<0.001 in males) in all binucleated cells, with a steeper slope in females (0.1758) than in males (0. 1241). Analysis using the 2x2 chi-square (chi(2)) test on the frequencies of MN-21 showed significant age-related differences in both males and females, except males in Group III and Group IV (p>0. 05). A significant sex-related difference was found only in subjects over 60 years (p<0.05), with females having more MN-21 (12.57 per thousand vs. 8.43 per thousand) than males. Loss of chromosome 21, occurring at mean levels of 0.38 per thousand in all binucleated cells and 0.24 per thousand in binucleated cells containing four FISH signals, was shown not to be age- or sex-related. A positive age-related increase in nondisjunction of chromosome 21 was shown in males (r=0.50, p<0.01), females (r=0.61, p<0.001) and all subjects (r=0.55, p<0.001) by linear regression analysis. An age effect was found only between children and adults (p<0.01 for females, p<0.05

NFATz: a novel rel similarity domain containing protein

Nuclear Factor of Activated T cell (NFAT) is a family of transcription factors that are important for the coordinate expression of various cytokines and immunoregulatory cell surface molecules in T cells and other types of cells in the immune system. In addition, analysis of gene disrupted mice revealed that some members of NFAT family are important for the development of myocardium, myocardial hypertrophy, and mesenchymal stem cells. NFAT family proteins have two conserved domains, the NFAT Homology Domain (NHD) and the Rel Similarity Domain (RSD). The RSD is DNA binding and AP-1 interacting domain which has structural similarity to the Rel Homology Region, the DNA binding domain of Rel family proteins. The NHD is a regulatory domain required for the Ca regulated translocation of NFAT. We report here the isolation and initial characterization of a novel RSD containing protein designated NFATz. NFATz has a RSD but no NHD. NFATz protein is localized in the nucleus without Ca signal. There is no detectable binding to a typical NFAT site even in the presence of AP-1, and it is not capable of activating transcription through the NFAT site. The chromosomal location determined by FISH revealed that NFATz and NFATx genes are in the same region.

[Effect of raw radish on pharmacological action of ginseng]

Ginseng decoction can increase the memory-improvement, weary-resistance, antihypoxia, sedation in mice, and increase the weight of spleen and accessory sexual gland, but reduce the weight of thymus. Raw radish can decrease these pharmacological effects in varying degrees, except the sedation.

Pulmonary artery perfusion with protective solution reduces lung injury after cardiopulmonary bypass

BACKGROUND

The inflammatory response and higher temperature of lung tissue during cardiopulmonary bypass can result in lung injury. This study was to evaluate the protective effect of pulmonary perfusion with hypothermic antiinflammatory solution on lung function after cardiopulmonary bypass.

METHODS

Twelve adult mongrel dogs were randomly divided into two groups. The procedure was carried out through a midline sternotomy, cardiopulmonary bypass was established using cannulas placed in the ascending aorta, superior vena cava, and right atrium near the entrance of the inferior vena cava. After the ascending aorta was clamped and cardioplegic solution infused, the right lung was perfused through a cannula placed in the right pulmonary artery with 4 degrees C lactated Ringer's solution in the control group (n = 6) and with 4 degrees C protective solution in the antiinflammation group (n = 6). Antiinflammatory solution consisted of anisodamine, L-arginine, aprotinin, glucose-insulin-potassium, and phosphate buffer. Plasma malondialdehyde, white blood cell counts, and lung function were measured at different time point before and after cardiopulmonary bypass; lung biopsies were also taken.

RESULTS

Peak airway pressure increased dramatically in the control group after cardiopulmonary bypass when compared with the antiinflammation group at four different time points (24 +/- 1, 25 +/- 2, 26 +/- 2, 27 +/- 2 cm H2O versus 17 +/- 2, 18 +/- 1, 17 +/- 1, 18 +/- 1 cm H2O; all p < 0.01). Pulmonary vascular resistance increased significantly in the control group than in the antiinflammation group at 5 and 60 minutes after cardiopulmonary bypass (1,282 +/- 62 dynes x s x cm(-5) versus 845 +/- 86 dynes x s x cm(-5) and 1,269 +/- 124 dynes x s x cm(-5) versus 852 +/- 149 dynes x s x cm(-5), p < 0.05). Right pulmonary venous oxygen tension (PvO2) in the antiinflammation group was higher than in the control group at 60 minutes after cardiopulmonary bypass (628 +/- 33.3 mm Hg versus 393 +/- 85.9 mm Hg, p < 0.05). The ratio of white blood cells in the right atrial and the right pulmonary venous blood was lower in the antiinflammation group than in the control group at 5 minutes after the clamp was removed (p < 0.05). Malondialdehyde were lower in the antiinflammation group at 5 and 90 minutes after the clamp was removed (p < 0.01 and p < 0.05, respectively). Histologic examination revealed that the left lung from both groups had marked intraalveolar edema and abundant intraalveolar neutrophils, whereas the right lung in the control group showed moderate injury and the antiinflammation group had normal pulmonary parenchyma.

CONCLUSIONS

Pulmonary artery perfusion using hypothermic protective solution can reduce lung injury after cardiopulmonary bypass.

The genome sequence of Drosophila melanogaster

The fly Drosophila melanogaster is one of the most intensively studied organisms in biology and serves as a model system for the investigation of many developmental and cellular processes common to higher eukaryotes, including humans. We have determined the nucleotide sequence of nearly all of the approximately 120-megabase euchromatic portion of the Drosophila genome using a whole-genome shotgun sequencing strategy supported by extensive clone-based sequence and a high-quality bacterial artificial chromosome physical map. Efforts are under way to close the remaining gaps; however, the sequence is of sufficient accuracy and contiguity to be declared substantially complete and to support an initial analysis of genome structure and preliminary gene annotation and interpretation. The genome encodes approximately 13,600 genes, somewhat fewer than the smaller Caenorhabditis elegans genome, but with comparable functional diversity.

[The influence of different root length on stress distribution in the bone around abutment root of telescopic overdenture]

OBJECTIVE

To investigate the influence of bone height around the roots on stress distribution in a mandible with two canines remained and covered with an telescopic overdenture.

METHODS

Three-dimensional finite element method.

RESULTS

As the height of the bone around the roots decreased, the stress increased. But the maximum stress in the bone in this study is lower than that in the bone around the canine under normal condition.

CONCLUSION

In the mandible, when the alveolar bone resorption reaches the apical 1/3 of canine (root length 4, 5 mm), if part of the tooth crown was removed, to make an acceptable crown/root ratio, so the canine can be used as the abutment of an overdenture.

Role of the TATA binding protein-transcription factor IIB interaction in supporting basal and activated transcription in plant cells

The TATA binding protein (TBP) and transcription factor IIB (TFIIB) play crucial roles in transcription of class II genes. The requirement for TBP-TFIIB interactions was evaluated in maize cells by introducing mutations into the Arabidopsis TBP (AtTBP2) within the C-terminal stirrup. Protein binding experiments indicated that amino acid residues E-144 and E-146 of AtTBP2 are both essential for TFIIB binding in vitro. Activation domains derived from herpes simplex viral protein VP16, the Drosophila fushi tarazu glutamine-rich domain (ftzQ), and yeast Gal4 were tested in transient assays. TBP-TFIIB interactions were dispensable for basal transcription but were required for activated transcription. In general, activated transcription was more severely inhibited by TBP mutation E-146R than by mutation E-144R. However, these TBP mutations had little effect on activity of the full-length cauliflower mosaic virus 35S and maize ubiquitin promoters, thus demonstrating that strong TBP-TFIIB contacts are not always required for transcription driven by complex promoters.

The regulation of caveolin expression and localization by serum and heparin in vascular smooth muscle cells

Caveolae have been implicated in growth factor receptor and G-protein coupled receptor signaling in vascular cells. It has been postulated that caveolin, the structural protein of caveolae, may act as a general tyrosine kinase inhibitor by binding and inhibiting signaling molecules involved in the activation of the MAP kinase proliferation cascade. Using an in vitro model of VSMC proliferation, we found that serum stimulation caused a dose dependent decrease in both caveolin-1 and caveolin-2 protein levels in human coronary artery smooth muscle cells. Heparin, an inhibitor of VSMC proliferation, inhibited the serum-induced loss of caveolin-1 and caveolin-2. In addition, heparin caused an increase in both caveolin-1 and caveolin-2 localization to caveolae-enriched sucrose gradient membrane fractions when compared to serum alone. Taken together, caveolin may play an important role in the regulation of VSMC proliferation and heparin and serum have opposing effects on caveolin expression and localization in VSMC.

Complementation between HLA-DR4 (DRB1*0401) and specific H2-A molecule in transgenic mice leads to collagen-induced arthritis

We generated transgenic mice with DRB1*0401 gene with mutation in the beta2 domain (aa 110 and 139) for better interaction with mCD4. The DR4 transgene was introduced into H2-Aq (B10RQB3) and H2-Af (B10RFB3) to examine the role of DR4 in collagen arthritis. The HLA-DR molecules in these mice were found to be functional on the basis of their positive/negative selection of the Vbeta T cell repertoire. H2-Aq mice are resistant to porcine CII-induced arthritis. The RQB3/DR4 mice (H2Aq/DR4) developed severe collagen induced arthritis (CIA) when immunized with Porcine type II collagen while the negative littermates were resistant. RQB3.DR4 mice were also highly susceptible to CIA induced by Human CII while negative littermates got only mild disease. However, RFB3/DR4 mice (H2Af/ DR4) did not get CIA with any type II collagen. Therefore, the DR4 gene in the context of H2-Aq predisposes to severe arthritis but not in the context of H2-Af. Antibodies to renatured cyanogen bromide (CB) cleaved fragments of PII in RQB3/DR4 mice and negative littermates suggest that the presence of DR4 does not result in any differences in specificity of antibody response to CB fragments. These results indicate that a specific gene complementation occurring between DR4 and H2.Aq but not DR4 and H2Af promotes the induction of arthritis with PII and HII in these mice. A similar interaction may be involved between DR and DQ molecules in human RA.

Specific interactions with TBP and TFIIB in vitro suggest that 14-3-3 proteins may participate in the regulation of transcription when part of a DNA binding complex

The 14-3-3 family of multifunctional proteins is highly conserved among animals, plants, and yeast. Several studies have shown that these proteins are associated with a G-box DNA binding complex and are present in the nucleus in several plant and animal species. In this study, 14-3-3 proteins are shown to bind the TATA box binding protein (TBP), transcription factor IIB (TFIIB), and the human TBP-associated factor hTAF(II)32 in vitro but not hTAF(II)55. The interactions with TBP and TFIIB were highly specific, requiring amino acid residues in the box 1 domain of the 14-3-3 protein. These interactions do not require formation of the 14-3-3 dimer and are not dependent on known 14-3-3 recognition motifs containing phosphoserine. The 14-3-3-TFIIB interaction appears to occur within the same domain of TFIIB that binds the human herpes simplex virus transcriptional activator VP16, because VP16 and 14-3-3 were able to compete for interaction with TFIIB in vitro. In a plant transient expression system, 14-3-3 was able to activate GAL4-dependent beta-glucuronidase reporter gene expression at low levels when translationally fused with the GAL4 DNA binding domain. The in vitro binding with general transcription factors TBP and TFIIB together with its nuclear location provide evidence supporting a role for 14-3-3 proteins as transcriptional activators or coactivators when part of a DNA binding complex.

MRI evaluation of bone marrow of normal lumbar vertebra in the Chinese: normal patterns and preliminary quantitative study

OBJECTIVES

To establish the normal patterns of lumbar vertebral marrow in normal Chinese, to determine its normal value of relaxation times (T1 and T2), and to investigate the relationship between relaxation time and age or sex.

METHODS

320 of 1000 cases (sampled randomly) received MR imaging. According to the MRI findings of sagittal T1WI, marrow patterns were established. 268 cases were studied quantitatively (T1 and T2 measurements).

RESULTS

The normal bone marrow patterns of lumbar vertebra were divided into four main patterns (six subgroups). The normal values of relaxation times (T1 and T2) were measured. T1 or T2 value decreased with aging. No significant difference in T1 value between two sexes (< 40 years old: u = 0.4307, P > 0.50; > or = 40 years old: u = 0.554, P > 0.05). No significant difference was seen in T2 value between two sexes before 40 years old (u = 1.3628, P > 0.10), but significant difference after 40 years old (u = 2.1498, P < 0.05).

CONCLUSIONS

To establish the normal patterns of lumbar vertebral marrow and determine its normal values of relaxation times have important clinical value in the diagnosis of bone marrow diseases.

A logit analysis of the likelihood of leaving rural settings for registered nurses

This study examined the net effects of individual and community factors on the likelihood of registered nurses leaving current jobs using a logit analysis. Based on data from a survey of 2,509 rural nurses, four separate models were estimated and compared: one for nurses in rural settings as a whole and the other three for nurses in hospitals, skilled nursing facilities, and community/public health agencies. Results of the general model indicated that nurses' marital status, age, position, income, job satisfaction, and satisfaction with the community were significant determinants of the likelihood of leaving current jobs. Job satisfaction was the most significant factor, followed by satisfaction with the community. Findings from the models for three different employment settings were similar to those of the general model. However, the significance of factors and their strength of effect on nurses' decisions to leave or stay in their current jobs differed across the three types of facilities. Based on these findings rural nursing administrators and policy-makers should give priority to retention strategies that focus on improving the job environment. The development of different strategies for different groups of nurses (i.e., by age or marital status) and different types of facilities should increase the benefit/cost ratio. In addition, programs that involve rural health care agencies in community and economic development should be further explored as an avenue to increased nurse retention in rural areas.

Predicting the degree of rurality of physician assistant practice location

This study used a block multiple regression analysis to examine the impacts of different factors on the degree of rurality of physician assistants' (PAs') practice location and compared the power of each block of factors in predicting rurality. Differences in the models for PAs in primary care specialties and for PAs as a whole were also explored. The findings suggest that policies should provide support to PA students in primary care specialties and to rural-oriented PA education/training programs. Efforts to facilitate PA recruitment and retention should include, among other things, increasing practice responsibility/autonomy, broadening acceptance of PA prescriptive authority, and providing equitable reimbursement for nonphysician care of Medicare and Medicaid beneficiaries.

Returns to nursing education: rural and nonrural practice

This study uses data from a national sample of registered nurses to compare earnings of nurses in rural and nonrural practice. The comparisons, conditioned by the nurses' education level, are analogous to the concept of "returns to human capital investment" used in labor economics. A general linear model is applied within a framework of labor economics analysis. Results show that nurses with more education receive less for their investment if they practice in rural areas. Work experience and employment setting are also related to lower annualized earnings for rural practice. One exception to the otherwise consistent findings is that returns to advanced practice nursing are higher in rural areas. Results and policy implications are discussed.

[Influence of aging and sex on chromosome 21 segregation in human lymphocytes]

OBJECTIVE

To determine the influence of aging and sex on the segregation of chromosome 21.

METHODS

Lymphocytes were obtained from healthy donors of different ages, both sexes, and were treated with cytochalasin B. Binucleated cells were hybridized with chromosome 21 specific probe, and simultaneously, chromosome 21 loss and non-disjunction were detected.

RESULTS

The coefficients of correlation between age and binucleated cells containing 4, 2 and 6 signals were -0.35(P<0.01), 0.18 and 0.38(P<0.01) respectively. The coefficients of correlation between age and nondisjunction of chromosome 21 and micronuclei were 0.56(P<0.01) and 0.70(P<0.01) respectively.

CONCLUSION

There is a significant increase with age in the number of micronuclei and missegregation. Nondisjunction of chromosome 21 is much more frequent than loss in vivo and in vitro. No significant difference in nondisjunctioin between male and female was noted. Age effect is more significant in female than in male.

Effect of liposome-encapsulated total alkaloid of harmaline on rabbit lens epithelial cells: experimental study on the prevention of posterior capsule opacification

PURPOSE

To investigate whether liposome encapsulated total alkaloid of Harmaline (TAH) as a therapeutic agent is beneficial to prevention of posterior capsular opacification (PCO).

METHODS

Liposome-encapsulated TAH was prepared by modified freeze-thawing method. 0.1 ml of liposome-encapsulated TAH (0.2 mg/ml) was injected into the capsular bag during extracapsular lens extraction (ECLE) of each eye in total 10 rabbit eyes. Blank liposome or balance salt solution (BSS) was used as control. Slit-lamp examination and histopathological examination was used to evaluated capsule opacification. Intraocular pressure (IOP), density and morphology of corneal endothelia cells, the amplitude and latency of b wave of ERG were measured.

RESULTS

The inflammatory response was mild both in TAH treated and the control group. PCO formation occurred in the control group 2 weeks postoperatively, but the posterior capsule was clear in TAH treated eyes. 4 weeks and 8 weeks after operation, PCO occurred both in TAH treated and control eyes. However, it was milder in the TAH treated eyes. IOP remained at the normal level in all eyes. There was no difference in the density of corneal endothelial cells, and the amplitude and latency of b wave of ERG between TAH treated and control eyes. Histopathological study revealed that lens epithelial proliferation occurred 4 weeks and the Soemmerings ring developed 8 weeks postoperatively in the control eyes. However, only mild vacuolization and pkynotic changes of lens epithelial cells were found in TAH treated eyes. Transmmission electronic microscopy demonstrated that there were mild cytoplasm vacuolization and mitochondria swelling of lens epithelial cells in TAH treated eyes.

CONCLUSION

The results suggest that liposome encapsulated TAH can inhibit metaplasia and proliferation of lens epithelial cells in the rabbit eye without obvious toxicity to the eye tissue. It may be used as a potential agent to prevent the development of PCO.

Distribution of human lens crystallins and their sulphydryl contents of different age in two-dimension electrophoresis

PURPOSE

To analyze water-soluble (WS) human lens proteins of fetus, adult and age-related cataract by two-dimensional IEF/SDS-PAGE electrophoresis.

METHODS

DACM [N-(7-Dimethylamino-4-methyl-3-coumarinyl) maleimide] was used to determine the lens proteins sulphydryl (SH) content.

RESULT

Protein SH contents in WS lens proteins have no significant difference among fetus, adult and age-related cataract lens. This is different from the relative published results obtained in lens proteins of animal cataract model using similar SH detecting methods.

CONCLUSIONS

IEF/SDS-PAGE electrophoresis demonstrated that there were much more fragmentation of crystallins during lens development and cataractogenic process. It is suggested that this phenomenon is likely to be due to further conformational changes in the fragmented cyrstallins during aging and cataractogenic process.

Three-dimensional finite element analysis and comparison of stress distribution in overdentures supported with bar attachments and telescopic crowns

OBJECTIVE

To determine which one of the overdenture (OD) retainers was more beneficial to the abutments--the bar or the telescopic crown--and if a tooth could be used as an OD abutment when the supporting bone decreased to half of the root.

MATERIALS AND METHODS

The three-dimensional finite element method was used to investigate the stress distribution in a mandible with an overdenture supported by the roots of two canines. The two teeth were either connected with a bar attachment or restored with telescopic crowns, and were then restored with a complete overdenture. For each type of superstructure, the influence of bone height around the roots (no alveolar resorption and resorption to half of the root length) was analyzed under three loading conditions.

RESULTS

The most extreme stress values were located at the alveolar ridge crest of the bone around the root of the abutment. In the case of anterior loading, the largest compressive stress (LCS) in telescopic crown overdenture (TOD) was lower. When loaded posteriorly there was no obvious difference between bar attachment overdenture (BOD) and TOD. At the alveolar ridge crest around the root of the abutment, the stress value in the model with decreased bone level was higher than in the model with normal bone level, but the range was not significant.

CONCLUSION

1. In terms of stress in the alveolar bone, complete overdenture over telescopic crowns is more convenient than over bar attachments. 2. Stress increases as the height of the bone around the roots decreases, but the increment is less than 30%. It is important for an abutment with bone resorption to perform root amputation to obtain an acceptable crown/root ratio.

Ferrocene-conjugated m-phenylenediamine conducting polymer-incorporated peroxidase biosensors

The development and characteristics of a reagentless amperometric biosensor employing horseradish peroxidase incorporated in an electrochemically deposited ferrocene-modified phenylenediamine film on a glassy carbon electrode is reported. The horseradish peroxidase/poly(m-aminoanilinomethylferrocene)- modified glassy carbon electrode reagentless biosensor measured hydrogen peroxide and other organic peroxides in both aqueous and organic medium by reduction at a low applied potential of -0.05 V (vs Ag/AgCl) without interference from molecular oxygen. When modified with glucose oxidase, the new bienzyme electrode measured glucose sensitively and selectively, demonstrating the suitability of the above peroxide biosensor for other oxidoreductase enzyme-based biosensors.

Fiber-optic enzyme biosensor for direct determination of organophosphate nerve agents

A fiber-optic enzyme biosensor for the direct measurement of organophosphate nerve agents was developed. The basic element of this biosensor is organophosphorus hydrolase immobilized on a nylon membrane and attached to the common end of a bifurcated optical fiber bundle. The enzyme catalyzes the hydrolysis of organophosphate compounds to form stoichiometric amounts of chromophoric products that absorb light at specific wavelengths. The back-scattered radiation of the specific incident radiation was measured using a photomultiplier detector and correlated to the organophosphate concentration. The effects of buffer pH, temperature, and the units of enzyme immobilized on the steady-state and kinetic response of the biosensor were investigated to optimize the operating conditions for the fiber-optic enzyme biosensor. These conditions were then used to measure parathion, paraoxon, and coumaphos selectively without interference from carbamates and triazines. Concentrations as low as 2 microM can be measured in less than 2 min using the kinetic response. When stored in buffer at 4 degreesC the biosensor shows long-term stability.

[Preparation of liposome encapsulated daunorbicine and determination of daunorubicine of aqueous humor in rabbit eyes]

PURPOSE

To investigate the method of determination the concentration of daunorubicine(DNR) and liposome encapsulated daunorubicine(LDNR) of aqueous humor in rabbit eyes.

METHODS

After extracapsular lens extraction, 0.1 ml of 1 mg/ml DNA and LDNR were injected into the anterior chamber. At the 12, 24, 48 hours and 1 week after operation, the aqueous humor were aspirated to determine the concentration of DNR by high performance liquid chromatography(HPLC).

RESULTS

At the 12, 24, 48 hours after operation, DNR were determined in all eyes, but at one week after operation, the DNR could only be detected in LDNR group. The concentration of DNR in LDNR group were higher than DNR group.