[Research progress on the treatment of presbyopia]

Presbyopia is a physiological aging situation that the plasticity and elasticity of the lens and the function of the ciliary muscle become weaker, resulting in a decreased accommodation and inability to focus on near objects. Nowadays, there are many clinical strategies to correct presbyopia, each of which has its own advantages and disadvantages, however, there is no true sense of way to restore accommodation function. This article reviews both worldwide and domestic research on presbyopia, and analyzes and summaries the status quo as well as research progress of presbyopia correction modalities, surgical approaches, and drug therapies, hoping to provide a reference for clinical works.

[Value of the simplified JSTH score criteria in the early diagnosis of sepsis-associated disseminated intravascular coagulation]

Objective: To evaluate the early diagnostic value of various indicators in the simplified JSTH score criteria for sepsis-associated disseminated intravascular coagulation (DIC). Methods: A retrospective study was conducted. Patients admitted to Intensive Care Unit (ICU) of the Second Affiliated Hospital of Kunming Medical University from January in 2017 to December in 2018 were enrolled. Totally of 365 patients were recruited, with 224 males and 132 females. The simplified JSTH score criteria was used to diagnose DIC. The patients were divided into sepsis with DIC group and sepsis without DIC group according to the diagnostic criteria of sepsis. Platelet (PLT), fibrin degradation products (FDPs), prothrombin time (PT), antithrombin (AT), acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) scores, sequential organ failure assessment (SOFA) scores and the simplified JSTH scores were recorded on the first ICU day. Correlation analyses were conducted.Receiver operating characteristic (ROC) curves for diagnosis of DIC with each indicator were drawn to evaluate the diagnostic efficiency and predictive ability of 28-day mortality. Results: According to the simplified JSTH score, 143 cases of sepsis complicated with DIC were diagnosed. There were significant differences in PLT, FDP, AT, PT, APACHE Ⅱ score, SOFA score, 28-day mortality rate between the two groups (all P<0.01). It was shown by Pearson correlation analysis that the criteria has the best correlation with APACHEⅡ score and SOFA score (r=0.496 and 0.612, both P<0.01). The correlation between PLT and APACHE Ⅱ score or SOFA score was the best (r=-0.440 or-0.568, both P<0.01). It was shown by ROC curve that area under ROC curve (AUC) of PLT was 0.933, and the sensitivity and specificity was 93.0% and 85.0%, respectively. The 28-day mortality was predicted by using the indicators in the criteria. The AUG of AT was 0.813, and both the sensitivity (81.6%) and specificity (73.6%) were the highest. Conclusions: The simplified JSTH score criteria can be used for early diagnosis of sepsis-associated DIC and it is positively correlated with the severity of the disease. The correlation between PLT and the severity of disease is the best, and early diagnosis efficiency of PLT is the strongest. AT has a good predictive value for 28-day mortality.

Analysis of ITS1 sequences and genetic relationships between populations of ridgetail white prawn, Exopalaemon carinicauda, in the East China Sea

Internal transcribed spacer 1 (ITS1) sequences from wild-type Exopalaemon carinicauda (N = 124) from the East China Sea were amplified and sequenced. Sequences were polymorphic and ranged from 388 to 583 bp in length. The average content of GC in sequences was significantly higher than that of AT. Altogether, 604 mutant sites with 123 haplotypes were detected; 46.7% were polymorphic sites. The genetic diversity index of population Y was highest, and the lowest was population X. Eight microsatellite sequences were detected; the most-repeated sequences were (GA)n, (AG)n, (GT)n, (TG)n, (TC)n, and (CT)n. Analysis of molecular variance revealed that genetic differentiation among the four populations were very weak, or modest. A molecular evolutionary tree was constructed using the neighbor-joining method and MEGA 6.0, and the phyletic evolutionary relationships among several Palaemonidae species examined. The phylogenetic tree showed that individuals of the same species, as well as the species of the same genus, clustered together, consistent with morphological classifications.

Installing and thereafter removing an aberrant prosthesis elicited opposite remodelling responses in growing mouse temporomandibular joints

Temporomandibular joint (TMJ) displays a high remodelling capability. The current purpose was to investigate the differences between mandibular condylar remodelling responses of growing mice to installation and removal of unilateral anterior crossbite (UAC) prosthesis. Twenty-four mice were divided into one mock control group and two UAC groups. Unilateral anterior crossbite was created by installing a pair of prosthesis to left-side maxillary and mandibular incisors. Unilateral anterior crossbite was removed in removal group at 3 weeks but remained in UAC group. Temporomandibular joints were sampled at 7 weeks. Changes in condylar cartilage and subchondral bone were assessed by histology and in vivo micro-CT. Real-time PCR and immunohistochemistry were performed to evaluate expression changes in ADAMTS-5, MMP-3, MMP-9, MMP-13, IL-1, TNF-α, OPG and RANKL. Statistical analysis was performed at α = 0.05. Temporomandibular joint cartilage degradation was induced by UAC as previously reported but was reversed by removal of UAC. The dropped cartilage thickness, chondrocyte number and collagen II-positive area, the increased expression levels of Adamts-5, Mmp3, 9, 13, Tnf-α and Il-1β in cartilage, the decreased ratio of OPG/RANKL in both condylar cartilage and subchondral bone, the loss of TMJ subchondral bone and the increase in the TRAP-positive cells in subchondral bone were all reversed in the removal group (P < 0.05). The growing mouse TMJ condyle displays a high remodelling capability which can be degenerative and rehabilitative, respectively, in response to placement and thereafter removal of the aberrant prosthesis. Eliminating aberrant prosthesis is helpful to promote the degraded condyle to recover.

Clinical and genetic evaluation of DYT1 and DYT6 primary dystonia in China

BACKGROUND

Dystonia is defined as the presence of sustained involuntary muscle contractions, often leading to abnormal posture and movement. DYT1 is caused by a mutation in the TOR1A gene, whilst mutations in THAP1 gene have been identified as responsible for DYT6. The relative frequency and phenotype differences between DYT1 and DYT6 amongst Chinese primary dystonia patients have not been well-characterized.

PATIENTS AND METHODS

One hundred eleven unrelated Chinese patients with primary dystonia were screened for mutations in TOR1A and THAP1 genes, and correlate this with clinical presentation. Exon 5 of TOR1A and all three exons and exon-intron conjunctions in THAP1 were screened by direct sequencing.

RESULTS

Three subjects were found to have the GAG deletion in the TOR1A gene, and two patients were detected with THAP1 gene mutations/variations (c.224A>T, c.449A>C). The overall mutation frequency was 4.5% in this cohort with TOR1A mutations found in 2.7% and THAP1 mutations found in 1.8%. No mutations were detected in the controls composed of 100 normal Chinese subjects. The clinical presentations of the DYT1 cases included onset in the limbs that could progress to the generalized dystonia within several years but without cranial involvement. Whilst in the DYT6 cases, the onset was cranial or cervical and progresses very slowly.

CONCLUSION

The major clinical differences between DYT1 and DYT6 dystonia in China were the cranial involvement in DYT6 and progress to general dystonia within several years in DYT1.

Penetration of topically applied levofloxacin into eyes with thin-wall filtering bleb after trabeculectomy

PURPOSE

To investigate the comparative penetration of 0.3% levofloxacin eye drops into the aqueous humour between cataract patients with or without (control) thin-wall filtering blebs.

METHODS

One drop of 0.3% levofloxacin was administered to the eyes at 30-min intervals for 3.5 h before phacoemulcification for both groups. Aqueous humour samples (0.1-0.2 ml) were aspirated during surgery. The concentration of levofloxacin in the aqueous humour was determined by high-performance liquid chromatography. The Student's t-test, Pearson correlation, and chi(2) test were used to compare the data of the two groups. A P<0.05 was required for results to be considered statistically significant.

RESULTS

The levofloxacin concentration in the aqueous humour was significantly increased (P<0.0001) in the bleb (mean+SD: 3.7+/-2.3 microg/ml) vscontrol group (0.4+/-0.2 microg/ml). Intraocular pressure and the bleb area were not correlated with levofloxacin concentration.

CONCLUSION

The presence of thin-wall filtering blebs increases intraocular penetration of topically administered levofloxacin.

Enhanced expression of transglutaminase 2 in anterior polar cataracts and its induction by TGF-beta in vitro

BACKGROUND/AIMS

Transglutaminase activity has long been implicated in the cataract formation. However, the precise mechanism of how it is produced and involved in this process remains unclear. Here the authors sought to examine whether transglutaminase 2 (TGase 2) is expressed in lens epithelial cells from patients with anterior polar cataracts, to determine whether TGase 2 expression is induced by transforming growth factor (TGF-beta) in cultured lens epithelial cells, and to determine whether TGase 2 participates in the crosslinking of fibronectin in lens epithelial cells in vitro.

METHODS

Lens epithelial cells from anterior polar cataracts, nuclear cataracts, and non-cataractous clear lenses were examined for the expression of TGase 2 using reverse transcription-polymerase chain reaction, western blot analysis, and immunohistochemical analysis. The modulation of extracellular TGase 2 activity by TGF-beta was measured by the formation of fibronectin polymers and the incorporation of fluorescein cadaverine into extracellular matrix proteins. The effect of TGase 2 overexpression was analysed by immunofluorescence staining and western blot analysis of human lens epithelial (HLE) B-3 cells transiently transfected with TGase 2 gene.

RESULTS

The expression of TGase 2 mRNA and its protein was markedly enhanced in lens epithelial cells from patients with anterior polar cataracts. Treatment of HLE B-3 cells with TGF-beta caused an increase in TGase 2 protein, its extracellular activity, and the crosslinking of fibronectin. Transient transfection of HLE B-3 cells with the TGase 2 gene led to the increased production of fibronectin monomers and polymers.

CONCLUSIONS

This study shows that TGase 2 is overexpressed in lens epithelial cells from anterior polar cataracts and that TGF-beta may be a causative factor in the induction of TGase 2. The enhanced expression of TGase 2 might cause the accumulation and crosslinking of the extracellular matrix proteins and might play a part in anterior polar cataract development.

Building 3D-structural model of kappa opioid receptor and studying its interaction mechanism with dynorphin A(1-8)

AIM

To construct the 3D-structural model of human kappa opioid receptor (HKOR) and study its interacting mechanism with dynorphin A(1-8) (Dyn8).

METHODS

Comparative molecular modeling was applied to build the 7 transmembrane (TM) helical domain of HKOR using the bovine rhodopsin (OPSD) model as a template. Molecular dynamics was performed to minimize the HKOR model and to simulate the 3D-structure of Dyn8 based on the NMR results of dynorphin A(1-14). The extracellular loops (EL) were built by self-constructed database searching. DOCK4.0 program was performed to construct Dyn8 complex with HKOR.

RESULTS

(1) The model of HKOR was obtained and validated by theoretical and experimental data. (2) The Dyn8-HKOR interacting mechanism is reasonably explained: Side chain of residue Asp138 interacts with protonated nitrogen atom at the N-terminal residues of Dyn8 through electrostatic and hydrogen bonding, which play an important role in ligand binding with receptor. (3) Negatively charged amino acids in the second extracellular loop (EL2) as Asp223 and Glu209 interact with the C-terminal positively charged residues in Dyn8, and Glu209 is a likely determinant of peptide ligand specificity.

CONCLUSION

Some amino acid residues positioned in EL2, TM3, TM4, and TM5 form the binding site and therefore determine the selectivity of kappa peptide agonist.