Posterior Corneal Elevation after Small Incision Lenticule Extraction for Moderate and High Myopia

Purpose

To investigate the changes of posterior corneal elevation after small incision lenticule extraction (SMILE) for moderate and high myopia.

Methods

In this prospective study, fifty consecutive eyes of thirty patients (10 male, 20 female) who underwent SMILE for myopia and myopic astigmatism were included. Eyes were divided in two groups based on the preoperative spherical equivalent refraction: high myopia group (32 eyes, range -6.25D to -10.00D) and moderate myopia group (18 eyes, range -3.00D to -6.00D). Posterior corneal surfaces were measured by a Scheimpflug camera (Pentacam, Oculus Germany) preoperatively and 1 month, 3 months, 6 months and 12 months postoperatively. Posterior central elevation (PCE) and posterior mean elevation (PME) at 17 predetermined points in the central-4mm area above the best-fit sphere were analyzed.

Results

No significant difference in the amount of posterior corneal elevation changes in the high myopia group was noted over time (P = 0.23 and P = 0.94 for PCE and PME, respectively). Similarly, the changes in the moderate myopia group before and after SMILE were not significant either (P = 0.34 and P = 0.40 for PCE and PME). A statistically significant correlation was found between the residual bed thickness and the shift of the PCE in the high myopia group at 12 months postoperatively (r = 0.53, P = 0.01).

Conclusions

The results of this study suggest that the posterior corneal surface remain stable within one year after SMILE for both moderate and high myopia. The changes of PCE correlate to the residual bed thickness for high myopia. Long-term changes of posterior corneal surface need further investigation.     

A new method to determine optimum temperature and activation energies for enzymatic reactions

A new method for determination of the optimum temperature and activation energies based on an idea of the average rate of enzymatic reaction has been developed. A mathematical model describing the effect of temperature on a dimensionless activity for enzyme deactivation following the first-order kinetics has been derived. The necessary condition for existence of the function extreme of the optimal temperature has been applied in the model. The developed method has been verified using the experimental data for inulinase from Kluyveromyces marxianus.     

Evaluation of the anti-fatigue effects of a traditional herbal drug,Gongjin-dan,under insufficient sleep conditions: study protocol for a randomised controlled trial

BackgroundMany herbal medicines are traditionally used as anti-fatigue agents in east Asian countries; however, there is a dearth of clinical evidence supporting the anti-fatigue effects of such medicines and their mechanisms. This study is a feasibility trial to assess the clinical efficacy of Gongjin-dan (GJD) and verify its mechanisms by exploring fatigue outcomes, including endocrine and immunological biomarkers in humans.Methods/DesignTo investigate the anti-fatigue effects of GJD and the mechanism underlying these effects, a randomised, double-blind, placebo-controlled crossover clinical trial was designed. Participants (24 healthy male volunteers) will be hospitalised for 4 days (3 nights), during which acute fatigue and stress conditions will be induced by sleep deprivation, and GJD or a placebo will be administered (twice daily). The primary outcome will be changes in serum cortisol levels, measured in the morning, as an objective biomarker of sleep deprivation-induced fatigue and stress. The secondary outcomes will include: the Fatigue Severity Scale; the Brief Fatigue Inventory, and the Leeds Sleep Evaluation Questionnaire scores; levels of salivary cortisol, epinephrine, norepinephrine, oxidative stress-related biomarkers, homocysteine, and immunological factors; and heart rate variability. After a washout period of more than 4 weeks, a second treatment phase will commence in which participants who were previously administered the placebo will receive the drug and vice versa, following the same treatment regime as in the first phase.DiscussionThis study protocol provides a unique opportunity to enhance our understanding of fatigue and the effects of GJD on fatigue in terms of endocrine and immunological mechanisms by validating the study design and determining feasibility. Findings from this trial will help researchers to design a pilot or definitive clinical trial of traditional herbal medicine for chronic fatigue.

Trial registration

Korean National Clinical Trial Registry CRIS; KCT0001681, registered on 29 October 2015.     

Quality of Life Analysis and Smoking Correlation in Symptomatic Spine Osteoarthritis: A Nationwide Health Survey Analysis of an Elderly Population with EQ-5D

Objectives

To analyze quality of life in people with symptomatic spine osteoarthritis (OA) using the results of a cross-sectional, nationwide survey.

Materials and Methods

This study used data from the Fifth Korean National Health and Nutrition Examination Survey (KNHANES V-5; 2010–2012). After excluding ineligible subjects, the total number of subjects in the study was 8,963, including 4,091 males and 4,872 females. All participants reported disabilities related to spine OA. Plain radiographs of the spine were taken for all participants.

Results

Age, sex, smoking, drinking, education, and income level were significantly related to spine OA morbidity (P<0.05). OA morbidity was significantly higher in female ex-smokers (OR; 2.94, P<0.05). Quality of life (EQ-5D: L1~5) was significantly compromised in the group with spine OA compared to the group without spine OA (P<0.05). Overall, LQ 1, 2, 3, 4, and 5 domain scores were significantly higher in the group with spine OA (P<0.05). In the group with spine OA, quality of life was reduced on more than three questions for 34.3% of the group (EQ-5D: grade≥2); on two questions, for 18.5% of the group; and on one question, for 11.1% of the group. Mental stress, melancholy, and suicidal thinking were also more common in the group with spine OA (P<0.05). The group with radiographic spine OA but without symptoms did not have compromised EQ-5D scores, whereas the group with radiographic OA and symptoms showed a significantly reduced quality of life.

Conclusions

Quality of life was significantly reduced in the group with symptomatic spine OA in a large cross-sectional analysis. Physicians should consider quality of life in the treatment of patients with spine OA     

Dermatoglyphic traits in patients with cardiovascular disorders

Dermatoglyphic studies were carried out on 800 Japanese subjects. Digital dermal pattern types were classified into true whorls, double loops, ulnar loops, radial loops and arches. Both total and absolute ridge count were recorded. Subjects with hypertension, angina pectoris and myocardial infarction were compared with the remaining group of others who had not yet developed any of these disorders. Individuals with myocardial infarction had a significantly higher frequency of true whorls and a correspondingly lower frequency of ulnar loops than the control group. Total and absolute ridge counts were also significantly higher in myocardial infarction. Individuals with hypertension and angina pectoris were not significantly different in most dermatoglyphic traits from the controls. These observations suggest that antenatal factors may contribute to the etiology of myocardial infarction in man.