[Transscleral ciliary surgery in glaucoma:from destructive surgery to minimally invasive surgery].

Over the years, there has been significant advancement in the safety and effectiveness of external cyclosurgery for glaucoma. This progress ranges from the initial "cyclodestructive surgery" to modern cycloplasty techniques, expanding beyond end-stage glaucoma treatment. Notably, innovative approaches like micropulse transscleral cycloplasty and ultrasonic cycloplasty are now being employed in earlier stages of glaucoma with better visual acuity, qualifying as minimally invasive procedures. Through a comprehensive review of the historical evolution of external cyclosurgery, elucidation of the mechanisms, clinical outcomes, and potential complications associated with novel cycloplasty techniques, and integration of practical clinical insights, this article aims to furnish clinicians with a profound comprehension of external cyclosurgery for glaucoma.

[Research progression of visual evoked potential in glaucomatous visual function evaluation].

Visual evoked potential (VEP) is often used for the objective evaluation for impairment of visual function. Although these VEP-related tests have good results in the assessment of glaucoma, their application as routine tests in the clinical diagnosis of glaucoma is limited due to the time consumption and easy interference by the environment and the reliance on the experience of the doctors. However, several new VEP detection modes have emerged in the past decade, such as short-duration transient VEP and isolated check VEP. Preliminary studies have shown that both of them have good diagnostic ability in glaucoma, and more studies on the clinical application of these latest technologies are conducive to further understanding of their value in the visual function evaluation and follow-up of glaucoma. (Chin J Ophthalmol, 2020, 56: 61-65).

[The association between corneal biomechanical parameters and visual field progression in patients with normal tension glaucoma].

Objective: To evaluate the association between corneal biomechanical parameters and visual field (VF) progression in normal tension glaucoma (NTG) using the Corvis-ST device, and to evaluate the ability of corneal biomechanical parameters to predict the VF progression. Methods: Corneal biomechanical parameters of newly diagnosed NTG patients were obtained using Corvis-ST in the baseline follow-up visit. The VF progression was defined as a 4-point increase in the Advanced Glaucoma Intervention Study (AGIS) score compared to the baseline in three consecutive follow-up visits (per 3-6 months). Corneal biomechanical parameters were compared between progressive and nonprogressive VF loss eyes using the independent-sample t test and Mann-Whitney U test. Spearman correlation analysis was used to explore the relationship between the corneal biomechanical parameters and the VF progression. Receiver operating characteristic curves were studied for the parameters and the sensitivity and specificity for distinguishing between progressive and nonprogressive glaucomatous eyes. The areas under the receiver operating characteristic curves (AUC) were also evaluated. Results: Sixty patients with NTG were enrolled in this study. Among them, 12 were lost to follow-up. A total of 48 patients completed all follow-up visits on schedule. Eleven of them were excluded due to one or more uncontrolled intraocular pressure (IOP) during the follow-up (less than 30% IOP reduction from the baseline). Thirty-seven eyes of 37 diagnosed NTG patients were enrolled. Ten eyes reached a progression endpoint. There was no significant difference in age, central corneal thickness, axial length, baseline IOP or baseline VF between the two groups. There was significant difference in Time A1 [(7.10±0.17) ms vs. (7.37±0.28) ms, t=-3.357, P=0.002], Length A1 [1.74(1.61, 1.77) mm vs. 1.78(1.77, 1.79) mm, Z=-3.036, P=0.002], Velocity A1 [0.16(0.14, 0.16) m/s vs. 0.15(0.14, 0.15) m/s, Z=-2.627, P=0.009] and DefAmpl HC [(1.22±0.13) mm vs. (1.12±0.11) mm, t=2.601, P=0.013] between progressive and nonprogressive glaucomatous eyes. Correlation analysis showed that Time A1, Length A1, Velocity A1 and DefAmpl HC were correlated with VF progression (r=-0.521, -0.463, 0.401, 0.349, P<0.05) . Time A1 demonstrated the highest AUC (0.817, P=0.001), followed by Length A1 (0.780, P=0.003), Velocity A1 (0.734, P=0.012) and DefAmpl HC (0.713, P=0.022). The cut-off set of Time A1 was 7.2 ms, the sensitivity was 80.0%, and the specificity was 82.8%. Conclusions: There were differences in corneal biomechanical parameters between eyes with progressive and nonprogressive VF loss in patients with NTG. There were lower Time A1 and Length A1 values and higher Velocity A1 and DefAmpl HC values in progressive glaucomatous eyes. This indicates a quicker response to reach first degree applanation and a larger degree of corneal deformability in progressive eyes. It is predicted that the easier deforming of the cornea, the smaller tolerance of the sclera and lamina cribros on IOP, making the optic disc more vulnerably. This may be one of the causes of glaucomatous optic nerve damage. Time A1 was the best parameter to predict the progression of VF among the corneal biomechanical parameters obtained by Corvis-ST. (Chin J Ophthalmol, 2018, 54: 171-176).

[The vessel and primary glaucoma].

Glaucoma, as the first leading cause of irreversible blindness in the world, is a chronic progressive optic neuropathy. The pathogenesis of glaucoma is still not fully understood till now. A lot of studies about vascular diameter, tortuosity, location, disc perfusion, vascular regulation and systemic vascular factors had been conducted to investigate the relationship between the vascular states and glaucoma since vascular hypothesis proposed. However, direct and convincing evidence for primary mechanisms of glaucoma is still lacking. The development of OCT, especially the Angio-OCT makes the real time visualization and measurement of ocular perfusion in vivo possible, gives some new evidences of vascular dysfunction of optic nerve head associated with glaucoma, which enhancing thinking of the pathogenesis of glaucoma. This review summarizes the literatures on vascular factors associated with glaucoma to provide the references for clinical researches. (Chin J Ophthalmol, 2017, 53:791-796).

Culture conditions of human embryonic stem cells for differentiation into retinal vascular structure.

OBJECTIVE: This study sought to identify the suitable cell culture conditions for the in vitro-induced differentiation of human embryonic stem cells (hESCs) into retinal vascular tissue cell types. MATERIALS AND METHODS: To do this, we established four treatment groups. Group A was designed to culture hESCs in a three-dimensional system. The feeder cells and leukemia inhibitory factor (LIF) were removed in Group B. In group C, hESCs were cultured with a variety of pro-angiogenic growth factors. In group D, hESCs were cultured with intact retinal support cells and extracellular matrix. On days 15 and 30, the expression of platelet endothelial cell adhesion molecule 1 (PECAM1), α-smooth muscle actin (αSMA), and macrophage marker F4/80 were detected by immunofluorescence staining. ELISA was used to detect the expression of stromal cell-derived factor-1 (SDF-1). RESULTS: At both 15 and 30 day timepoints, the highest PECAM1, αSMA, and F4/80 positive rates and SDF-1 expression levels were observed in group D, followed by group C, group B, with group A presenting the lowest expression of these proteins (p<0.05). Also, group D showed obvious angiogenesis structures. CONCLUSIONS: Our study indicates that hESCs can differentiate into retinal vascular-like structures. The presence of intact retinal support cells, a variety of cytokines, and extracellular matrix components were essential to facilitate this differentiation.

[Research advances of optic nerve lamina cribrosa structure and its measurement analysis].

The lamina cribrosa (LC) is believed to be site of injury to retina ganglion cell axons in glaucoma. The ability to visualize this structure helps us increase the understanding of pathophysiological process of glaucoma. At the same time, it is helpful in the early detection and treatment of glaucoma. While for many years the researches on the LC were essentially dependent on histology. With the development of optical coherence tomography (OCT) in recent years, it is possible to image the LC in vivo in both animals and human. This review focused on the biomechanics of optic nerve and LC, recent advances in OCT imaging of LC, imaging processing and analysis. All of these will supply the ability to diagnose and monitor glaucoma, as well as to expand our recognition of its pathophysiology. (Chin J Ophthalmol, 2016, 52: 952-956).

The treatment outcomes of crescent-shaped conjunctiva resection combined with conjunctiva sclera fixation for severe conjunctivochalasis.

OBJECTIVE: To observe the treatment outcomes of a crescent-shaped conjunctiva resection combined with conjunctiva sclera fixation for severe conjunctivochalasis. PATIENTS AND METHODS: Eleven (22 eyes) patients with severe conjunctivochalasis were enrolled in this study. They consented to undergo crescent-shaped conjunctiva resection and conjunctiva sclera fixation, to evaluate their symptoms and inspect the lacrimal fluid system. This included the breakup time of the tear film, height and integrity of the lacrimal river, bulbus oculi fluorescein staining pre-operation and 6 m-post-operation. RESULTS: Within the 22 eyes, the symptoms disappeared or improved in 20 eyes (90.9%). Compared with before the surgery, the tear inspections improved after the surgery. The difference was statistically significant. CONCLUSIONS: Crescent-shaped conjunctiva resection combined with conjunctiva sclera fixation is safe and effective for severe conjunctivochalasis.

Autophagy in drug resistance of the multiple myeloma cell line RPMI8226 to doxorubicin.

We investigated the effect of autophagy on drug resistance of multiple myeloma (MM) to doxorubicin (DOX). A DOX-resistant MM cell line (RPMI8226/DOX) was developed by progressively increasing the DOX concentration gradient. The drug resistance index was determined using the MTT method. Transmission electron microscopy, anti-light chain 3-fluorescein isothiocyanate immunofluorescence, and Western blotting were used to detect autophagy of MM cells. Flow cytometry was applied to detect changes in apoptosis of RPMI8226/DOX cells (stained with annexin-V/propidium iodide) caused by inhibition by hydroxychloroquine and 3-methyladenine on autophagy. The drug resistance index of RPMI8226/DOX to DOX was 10.8, and autophagy/lysosomal was clearly observed in RPMI8226/DOX cells under transmission electron microscopy, while immunofluorescence showed granular immunofluorescence in cells. Western blot analysis showed that light chain 3-II protein expression level was higher in RPMI8226/DOX cells than in RPMI8226/S cells. The apoptosis test showed that hydroxychloroquine or 3-methyladenine partially reversed the drug resistance of RPMI8226/DOX cells by inhibiting autophagy. Activation of autophagy in MM cells may explain the drug resistance of myeloma.

Exogenous NO depletes Cd-induced toxicity by eliminating oxidative damage, re-establishing ATPase activity, and maintaining stress-related hormone equilibrium in white clover plants.

Various nitric oxide (NO) regulators [including the NO donor sodium nitroprusside (SNP), the NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO), the NO-synthase inhibitor N (G)-nitro-L-Arg-methyl ester (L-NAME), and the SNP analogues sodium nitrite/nitrate and sodium ferrocyanide] were investigated to elucidate the role of NO in white clover (Trifolium repens L.) plants after long-term (5 days) exposure to cadmium (Cd). A dose of 100 µM Cd stress significantly restrained plant growth and decreased the concentrations of chlorophyll and NO in vivo, whereas it disrupted the balance of stress-related hormones and enhanced the accumulation of Cd, thereby inducing reactive oxygen species (ROS) burst. However, the inhibition of plant growth was relieved by 50 µM SNP through its stimulation of ROS-scavenging compounds (ascorbic acid, ascorbate peroxidase, catalase, glutathione reductase, non-protein thiol, superoxide dismutase, and total glutathione), regulation of H(+)-ATPase activity of proton pumps, and increasing jasmonic acid and proline but decreasing ethylene in plant tissues. Even so, the alleviating effect of SNP on plant growth was counteracted by cPTIO and L-NAME and was not observed with SNP analogues, suggesting that the protective roles of SNP are related to the induction of NO. These results suggest that NO may improve the Cd tolerance of white clover plants by eliminating oxidative damage, re-establishing ATPase activity, and maintaining hormone equilibrium. Improving our understanding of the role of NO in white clover plants is key to expanding the plantations to various regions and the recovery of pasture species in the future.

Salmonella L-forms: formation in human bile in vitro and isolation culture from patients' gallbladder samples by a non-high osmotic isolation technique.

Bacterial L-forms have always been considered as osmotic-pressure-sensitive cell-wall-deficient bacteria and isolation culture of L-forms must use media with high osmotic pressure. However, isolation culture of stable L-forms formed in humans and animals is very difficult because they have adapted to the physiological osmotic pressure condition of the host. We use a non-high osmotic isolation technique to isolate stable L-forms of Salmonella Typhi and Salmonella Paratyphi A from bile-inducer cultures in vitro and from patients' gallbladder specimens. Multiplex PCR assay for Salmonella-specific genes and nucleotide sequencing are used to identify the Salmonella L-forms in stable L-form isolates. Using this method, we confirmed that Salmonella Paratyphi A and Salmonella Typhi cannot be isolated from bile-inducer cultures cultured for 6 h or 48 h, but the L-forms can be isolated from 1 h to 45 days. In the 524 gallbladder samples, the positive rate for bacterial forms was 19.7% and the positive rate for Salmonella spp. was 0.6% by routine bacteriological methods. The positive rate for bacterial L-forms was 75.4% using non-high osmotic isolation culture. In the L-form isolates, the positive rate of Salmonella invA gene was 3.1%. In these invA-positive L-form isolates, four were positive for the invA and flic-d genes of Salmonella Typhi, and ten were positive for the invA and flic-a genes of Salmonella Paratyphi A.

Enhanced excitatory synaptic network activity following transient group I metabotropic glutamate activation.

Prolonged activation of group I metabotropic glutamate receptors (mGluRs) using the agonist (S)-3,5-dihydroxyphenylglycine (DHPG) produces long-lasting changes in the CA3 region of the hippocampal slice. Changes in CA3 pyramidal neuron excitability that follow DHPG exposure result in abnormal network activity manifest by epileptiform activity that consists of interictal and longer lasting ictal epileptiform discharges. In this study we evaluated changes in synaptic activity of CA3 neurons in rat hippocampal slices that occurred after exposure to DHPG. Whole-cell voltage-clamp recordings were made from visually identified CA3 neurons in control artificial cerebrospinal fluid at times greater than 1h after DHPG exposure. Compared to control slices, neurons from slices exposed to DHPG showed enhanced amplitude and frequency of spontaneously occurring excitatory postsynaptic currents (EPSCs) without a concurrent change in inhibitory postsynaptic current (IPSC) amplitude or frequency. Miniature EPSCs were not affected by DHPG exposure but mIPSCs occurred less frequently and were of reduced amplitude. IPSCs recorded in the presence of ionotropic glutamate receptor blockade occurred less frequently in neurons that had been exposed to DHPG. Monosynaptic-evoked IPSPs were also reduced in amplitude in neurons that had been exposed to DHPG. Taken together, these findings demonstrated an enhanced network excitability of the CA3 region and failure of compensatory synaptic inhibition. We propose that prolonged activation of group I mGluR that may occur under conditions of pathological glutamate release results in long-lasting changes in CA3 synaptic network activity and epileptiform activity driven by excessive synaptic excitation.

Solexa sequencing of microRNAs on chromium metabolism in broiler chicks.

AIM: The aim of this study was to determine the effect of chromium picolinate (CrPic) on the differential expression of the known microRNAs (miRNAs) in broiler skeletal muscle. METHODS AND RESULTS: A total of 288 1-day-old male Arbor Acres broilers were randomly assigned to one of four dietary treatments supplemented with 0, 0.4, 2.0, or 10.0 mg·kg(-1) CrPic, respectively. Dietary CrPic supplementation at 10.0 mg·kg(-1) increased the average daily feed intake in broilers (p < 0.05). On day 42, the serum total protein level was highest in animals treated with 2.0 mg·kg(-1) (p < 0.05) and 10.0 mg·kg(-1) CrPic (p < 0.05). Dietary supplementation with 10.0 mg·kg(-1) CrPic decreased the levels of serum glucose (p < 0.05) on day 42 and of serum triglyceride (p < 0.05) on days 21 and 42. To further identify miRNAs from broiler skeletal muscles, we sequenced two small RNA libraries using the Solexa sequencing approach, and 57 miRNAs were found to be significantly differentially expressed (p < 0.05). Among them, 6 upregulated and 2 downregulated miRNAs were validated by real-time qPCR (p < 0.05). CONCLUSIONS: The results of the present study provide a valuable clue regarding the role of miRNA target genes in the mechanism of the dietary CrPic effect on protein synthesis in skeletal muscles of broilers.

Iron homeostasis in osteoporosis and its clinical implications.

Osteoporosis has until now been considered to be a disease associated with abnormal calcium metabolism. However, an increasing number of clinical observations strongly suggest the association of iron overload with bone diseases, particularly in osteoporosis in menopausal women. The recent identification of hepcidin sheds new light into the crucial role of iron homeostasis in bone metabolism. Decreasing iron overload in cell studies as well as in animal experiments has been shown to improve bone cell metabolism and growth in vitro and in vivo. In view of the significant iron overload found in the aging population, especially in females, the therapeutic potential of lowering iron overload for the treatment of osteoporosis is suggested.

Resistive and capacitive response of nitrogen-doped TiO2 nanotubes film humidity sensor.

Dielectric oxides are traditionally used to fabricate resistive surface humidity-sensing devices, as well as capacitive sandwich-structured sensors. In the present work, relative humidity (RH) sensors were fabricated by employing vertically aligned TiO(2) nanotubes array (TNA) film produced using electro-chemical anodization of Ti foil followed by a nitrogen-doping process, simultaneously showing resistive and capacitive humidity-sensing properties in the range of 11.3-93.6%. For the sample formed at optimized experimental conditions, the capacitance (C(S)) and resistance (R(S)) of the as-fabricated RH sensors made from nitrogen-doped TiO(2) nanotubes film could be simultaneously obtained. Both the resistive and capacitive sensitivity (K(R) and K(C)) of the as-fabricated TiO(2) nanotube RH sensors show distinct dependence on the frequency of alternating current (AC) voltage signal and RH. At higher water coverage, water-water interaction will result in lowering of the water dissociation barrier, leading to an increase of conductance. With the increase of RH, the polarization of as-adsorbed water molecules will also occur, causing a sharp increase of capacitance. For an explanation of the frequency response of both C(S) and R(S), ionic transport, as well as the polarization effect, should be comprehensively considered. The changes of capacitance and resistance at different temperatures are plausibly caused by thermal expansion and surface state modification by adsorption and desorption of oxygen and water.

Acetylcholine attenuates synaptic GABA release to supraoptic neurons through presynaptic nicotinic receptors.

Both inhibitory GABAergic and excitatory glutamatergic inputs to supraoptic nucleus (SON) neurons can influence the release of vasopressin and oxytocin. Acetylcholine is known to excite SON neurons and to increase vasopressin release. The functional significance of cholinergic receptors, located at the presynaptic nerve terminals, in the regulation of the excitability of SON neurons is not fully known. In this study, we determined the role of presynaptic cholinergic receptors in regulation of the inhibitory GABAergic inputs to the SON neurons. The magnocellular neurons in the rat hypothalamic slice were identified microscopically, and the spontaneous miniature inhibitory postsynaptic currents (mIPSCs) were recorded using the whole-cell voltage-clamp technique. The mIPSCs were abolished by the GABA(A) receptor antagonist, bicuculline (10 microM). Acetylcholine (100 microM) significantly reduced the frequency of mIPSCs of SON neurons from 3.59+/-0.36 to 1.62+/-0.20 Hz (n=37), but did not alter the amplitude and the decay time constant of mIPSCs. Furthermore, the nicotinic receptor antagonist, mecamylamine (10 microM, n=13), eliminated the inhibitory effect of acetylcholine on mIPSCs of SON neurons. The muscarinic receptor antagonist, atropine (100 microM), did not alter significantly the effect of acetylcholine on mIPSCs in most of the 17 SON neurons studied. These results suggest that the excitatory effect of acetylcholine on the SON neurons is mediated, at least in part, by inhibition of presynaptic GABA release. Activation of presynaptic nicotinic receptors located in the GABAergic terminals plays a major role in the cholinergic regulation of the inhibitory GABAergic input to SON neurons.

[Preliminary study of analgesic mechanism of Buthus martensii Karsch (BmK) venom on central nervous system].

AIM: To investigate whether or not the lateral septal nucleus (LS) was one of important analgesic areas of BmK venom in the central nervous system (CNS), and, targeting on which receptor, analgesic effect was produced by it. METHODS: Pain threshold of skin was observed by the latent period of tail flick evoked by radiant heat. Glass micropipette placed in Pf was used to record unit discharges of neurons in it, before and after 0.01% BmK venom were injected into LS. Stainless steel cannula placed in the lateral cerebral ventricle (icy) and LS was used for microinjection. RESULTS: After injection of 2 microl 0.01% BmK venom into icy of rat, the pain threshold was apparently raised, which was completely returned by injection of 0.5 microl 0.25% naloxone into icy. After 0.5 microl 0.01% BmK venom was injected into LS, 71% (15/21) nociceptive-on neurons and 83.3% (5/6) nociceptive-off neurons decreased the nociceptive response to tail pinch, but no evident effect was observed in the non-nociceptive neurons. CONCLUSION: The analgesic effect of BmK venom was probably realized mainly by the opiate receptor, and LS was one of important analgesic areas of BmK venom on CNS.

Genetic polymorphism of 4'-hydroxylation of S-mephenytoin in 148 Chinese of Han nationality.

AIM: To study genetic polymorphism of S-mephenytoin (S-Mep) 4'-hydroxylation in the Chinese population of Han nationality. METHODS: The lg metabolic ratio (MR) and lg hydroxylation index (HI) in the urine (0-12 h) after oral administration with 100 mg of racemic Mep tablet were determined by HPLC method in 148 consangeously unrelated native Chinese subjects and 21 individuals of 5 families. RESULTS: The lg MR and lg HI showed a bimodal distribution with an antimode of -1.00 and 1.50, respectively. The occurrence of poor metabolizers (PM) was 13.5% in the population. The pedigree analysis in 5 families indicated that deficient S-Mep hydroxylation was an autosomal recessive trait. CONCLUSIONS: The occurrence of PM for S-Mep 4-hydroxylation in Chinese was higher than that of the Caucasians, and both genetic modes were of autosomal recessive trait.