Risk Factors for Progressive Visual Field Loss in Primary Angle-Closure Glaucoma: A Retrospective Cohort Study

Purpose

To investigate risk factors associated with progressive visual field (VF) loss in primary angle closure glaucoma (PACG).

Methods

We retrospectively reviewed medical record of PACG patients who had ≥5 reliable VF examinations (central 24-2 threshold test, Humphrey Field Analyzer) and ≥2 years of follow-up. Each VF was scored using Collaborative Initial Glaucoma Treatment Study system. Progression was defined if 3 consecutive follow-up VF tests had an increased score of ≥3 above the mean of the first 2 VF scores. Factors associated with VF progression were evaluated by Cox proportional hazards models.

Results

A total of 89 eyes from 89 patients (mean age, 69.8 ± 7.9 years), who received a mean of 6.9 ± 2.3 VF tests (mean deviation at initial, -8.1 ± 4.4 dB) with a mean follow-up of 63.9 ± 23.9 months were included. VF progression was detected in 9 eyes (10%). The axial length (AL), anterior chamber depth, and intraocular pressure (IOP) in patients with and without progression were 22.5 ± 0.6 and 23.1 ± 0.9 mm, 2.5 ± 0.3 and 2.5 ± 0.3 mm, 14.8 ± 2.4 and 14.3 ± 2.3 mm Hg, respectively. AL was the only factor associated with progression in both Cox proportional hazards univariate (p = 0.031) and multivariate models (p = 0.023).

Conclusion

When taking into account age, IOP, follow-up period, and number of VF tests, a shorter AL is the only factor associated with VF progression in this cohort of Chinese patients with PACG. Further studies are warranted to verify the role of AL in progressive VF loss in PACG.     

Jatropha curcas L. (Euphorbiaceae) exhibits a mixed mating system, high correlated mating and apomixis

The hierarchical mating system among and within fruits of Jatropha curcas was investigated in a base population using five microsatellite loci, employing mixed mating and correlated mating models. Open-pollinated fruits were collected from 15 randomly selected seed trees, sampling seven fruits per tree for a total of 21 seeds from each tree. We detected multilocus genotypes identical to the mother tree in 13 % of offspring, implying the occurrence of apomixis in J. curcas. The presumed apomictic individuals were excluded from the analysis of the remaining results. Evidence of substantial selfing was provided by the average multilocus outcrossing rate (t _m?=?0.683), showing that the species exhibits a mixed mating system. The outcrossing rate showed a large variation among seed trees, ranging from 0.21 to 1.0, indicating that the species is not self-incompatible. Significant differences were detected between the multilocus and the single locus outcrossing rates (t _m???t _s?=?0.347) that suggested mating among related individuals, possibly because of the presence of individuals from the same progeny (sibs) in the base population. The multilocus paternity correlation was extremely high for the population (r _p(m)?=?0.999), indicating that the progenies were manly composed of full-sibs. As a consequence of selfing and a high paternity correlation, the co-ancestry coefficient within the progeny was higher (Θ?=?0.369) than expected for panmictic populations. Our results indicated that J. curcas produces seeds asexually by apomixis and sexually by a mixed mating system, combining selfing and outcrossing.     

Isolation and characterization of yeast nicotinamide adenine dinucleotide kinase.

NAD+ kinase (ATP:NAD+ 2'-phosphotransferase, EC 2.7.1.23) from yeast has been purified utilizing ion-exchange and NAD+-agarose affinity chromatography to give a 2100-fold purification. The apparent homogeneity of the enzyme preparation was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis and analytical ultracentrifugation. The enzyme has a subunit molecular weight of 31,000, and a native molecular weight of 124,000, and is, thus, probably a tetramer. The single form of the enzyme has an apparent isoelectric point of 5.85. Initial velocity studies in the forward direction with both substrates gave intersecting Lineweaver-Burk plots, and this suggests a sequential mechanism in which both substrates are bound before products are released. Replots of these data were linear and gave Km values for NAD+ and ATP of 0.68 mM and 2.3 mM, respectively.     

Characterization of Recombinant Human Cardiac KCNQ1/KCNE1 Channels (I Ks) Stably Expressed in HEK 293 Cells

The present study was designed to characterize pharmacological, biophysical and electrophysiological properties of the recombinant human cardiac I _Ks (KCNQ1/KCNE1) channels at physiological temperature. Human cardiac KCNQ1 and KCNE1 genes were cotransfected into HEK 293 cells, and a cell clone stably expressing both genes was selected. Membrane currents were recorded using a perforated patch-clamp technique. The typical I _Ks was slowly activated upon depolarization voltages in HEK 293 cells stably expressing human cardiac KCNQ1 and KCNE1 genes, and the current was inhibited by I _Ks blockers HMR 1556 and chromanol 293B, with 50% inhibitory concentrations (IC₅₀s) of 83.8 nM and 9.2 μM, respectively. I _Ks showed a significant temperature-dependent increase in its magnitude upon elevating bath temperature to 36°C from room temperature (21°C). The current was upregulated by the β-adrenoceptor agonist isoproterenol, and the effect was reversed by H89. In addition, I _Ks was inhibited by Ba²⁺ in a concentration-dependent manner (IC₅₀ = 1.4 mM). Action potential clamp revealed a “bell-shaped” time course of I _Ks during the action potential, and maximal peak current was seen at the plateau of the action potential. A significant use- and frequency-dependent increase of I _Ks was observed during a train of action potential clamp. These results indicate that the recombinant human cardiac I _Ks stably expressed in HEK 293 cells is similar to native I _Ks in drug sensitivity and regulated by Ba²⁺ and β-adrenoceptor via the cyclic adenosine monophosphate/protein kinase A pathway. Importantly, the current exhibits significant temperature dependence, a bell-shaped time course during action potential and prominent use- or frequency-dependent accumulation during a train of action potentials.     

Seroepidemiology of <Emphasis Type="Italic">Klebsiella pneumoniae</Emphasis> colonizing the intestinal tract of healthy chinese and overseas chinese adults in Asian countries

Background  

Capsular serotypes K1 and K2 of Klebsiella pneumoniae are thought to the major virulence determinants responsible for liver abscess. The intestine is one of the major reservoirs of K. pneumoniae, and epidemiological studies have suggested that the majority of K. pneumoniae infections are preceded by colonization of the gastrointestinal tract. The possibility of fecal-oral transmission in liver abscess has been raised on the basis of molecular typing of isolates. Data on the serotype distribution of K. pneumoniae in stool samples from healthy individuals has not been previously reported. This study investigated the seroepidemiology of K. pneumoniae isolates from the intestinal tract of healthy Chinese in Asian countries. Stool specimens from healthy adult Chinese residents of Taiwan, Japan, Hong Kong, China, Thailand, Malaysia, Singapore, and Vietnam were collected from August 2004 to August 2010 for analysis.     

Influence of ethanol on the release of growth factors in human blood-derived platelet gels

Platelet gels (PG) are new topical single-donor blood products which are attracting great interest in regenerative medicine. They are obtained by mixing a platelet-rich plasma fraction with thrombin to generate a fibrin gel enriched in platelet growth factors (GF). The type of thrombin preparation may affect PG reproducibility. We have determined the impact of 14.6% (v/v) ethanol-stabilized thrombin (EHT) on the release of GF by platelets. Various ratios of EHT and platelet concentrates were mixed to obtain from 2.43 to 7.96% ethanol concentration. Platelet-derived growth factor-AB (PDGF-AB), transforming growth factor-ß1 (TGF-ß1), vascular endothelium growth factor (VEGF), epidermal growth factor (EGF), and insulin-like growth factor-1 (IGF-1) were assessed at 5, 120, and 300 min after PG formation. Protein profiles of thrombin and PG releasates were analyzed by SDS-PAGE. The amount of PDGF-AB, TGF-ß1, and VEGF released per platelet decreased significantly (p < 0.05) with increasing ethanol concentrations but, however, not that of EGF. IGF-1 content was stable, consistent with its presence mostly in plasma. SDS-PAGE indicated that ethanol did not affect fibrin formation. In conclusion, ethanol has a significant impact on the amount of GF released by platelets and should be strictly controlled to standardize PG and optimize clinical benefits.     

Temporal control of nuclear envelope assembly by phosphorylation of lamin B receptor

The nuclear envelope of metazoans disassembles during mitosis and reforms in late anaphase after sister chromatids have well separated. The coordination of these mitotic events is important for genome stability, yet the temporal control of nuclear envelope reassembly is unknown. Although the steps of nuclear formation have been extensively studied in vitro using the reconstitution system from egg extracts, the temporal control can only be studied in vivo. Here, we use time-lapse microscopy to investigate this process in living HeLa cells. We demonstrate that Cdk1 activity prevents premature nuclear envelope assembly and that phosphorylation of the inner nuclear membrane protein lamin B receptor (LBR) by Cdk1 contributes to the temporal control. We further identify a region in the nucleoplasmic domain of LBR that inhibits premature chromatin binding of the protein. We propose that this inhibitory effect is partly mediated by Cdk1 phosphorylation. Furthermore, we show that the reduced chromatin-binding ability of LBR together with Aurora B activity contributes to nuclear envelope breakdown. Our studies reveal for the first time a mechanism that controls the timing of nuclear envelope reassembly through modification of an integral nuclear membrane protein.