[Challenges and prospects in the application of artificial intelligence for ocular disease screening and diagnosis]

In recent years, artificial intelligence (AI) technologies have experienced substantial growth across various sectors, with significant strides made particularly in medical AI through advancements such as large models. The application of AI within the field of ophthalmology can enhance the accuracy of eye disease screening and diagnosis. However, the deployment of AI and its large models in ophthalmology still encounters numerous limitations and challenges. This article builds upon the transformative achievements in the medical AI sector and discusses the ongoing challenges faced by AI applications in ophthalmology. It provides forward-looking insights from an ophthalmic perspective regarding the era of large models and anticipates research trends in AI applications in ophthalmology, so as to foster the continuous advancement of AI technologies, thereby significantly promoting eye health.

Investigation of retinal microvasculature and choriocapillaris in adolescent myopic patients with astigmatism undergoing orthokeratology

Background

To observe alterations of fundus microcirculation and retinal thickness in adolescent myopic patients with astigmatism after toric and spherical orthokeratology using optical coherence tomography angiography (OCTA), to explore the effects of orthokeratology on the retinal thickness and choroidal blood flow.

Methods

A total of 48 patients were enrolled and divided into two group (toric orthokeratology (T) group and spherical orthokeratology (S) group) according to the type of lens design. OCTA was used to measure the superficial and deep retinal vessel densities at the macular region, radial peripapillary capillary (RPC) density, foveal avascular zone (FAZ) area, and choriocapillaris (ChC) perfusion area before and after orthokeratology for 3 months. The data were statistically analyzed by SPSS 19.0 software.

Results

Compared with before orthokeratology, the superficial vessel density in the fovea and parafovea in the T group significantly increased, and the deep vessel density in the whole area and fovea were significantly elevated after 3 months (P < 0.05). The superficial vessel density was significantly higher only in the parafovea in the S group after 3 months than that before orthokeratology (P < 0.05), deep vessel density in the whole area and parafovea after 3 months was significantly higher than that before orthokeratology (P < 0.05). RPC density in the two groups increased after 3 months of orthokeratology in the whole area and inside the disc area (P < 0.05).

Three months after toric orthokeratology, FAZ area in the T group was significantly reduced by 0.05 (− 0.41 to + 0.08) mm², while ChC perfusion area was enlarged by 0.06 ± 0.12 mm². FAZ area in the S group significantly decreased by 0.01 (− 0.19 to + 0.01) mm², whereas ChC perfusion area increased by 0.06 (− 0.07 to + 0.50) mm². Retinal thickness in the two groups increased after 3 months of orthokeratology in the whole area and parafoveal area (P < 0.05).

Conclusion

Orthokeratology improved retinal blood flow in macular area and RPC while controlling myopia. The changes in FAZ and ChC perfusion areas did not significantly differ between toric and spherical orthokeratology.

[Research advances on the characteristics of fibroblast in keloid]

In re-cent 20 years, the development of cell biology technology has promoted the research of keloid. Keloid fibroblasts (KFbs) are the main effector cells in keloid, which are closely related to the occurrence and development of keloid. It is significantly different in terms of biological characteristics and gene expression between KFbs and normal fibroblasts. This articles reviews the characteristics of KFbs from multiple perspectives, describing its biological character- istics in details including microstructures, metabolic character- istics, and proliferation properties, and introducing the main characteristics of heterogeneity and genomics of KFbs. The further research on KFbs will help to elucidate the pathogenesis of keloids and provide valuable strategies for the prevention and treatment of keloids.

[Progress in research on redistribution methods for garbage codes in causes of death data]

The existence of garbage codes in death cause surveillance data sets could influence the accuracy of the death cause statistics, and subsequently affect the precision and effectiveness of public health policy making. International and domestic researchers have studied the characteristics of garbage codes in various death cause data sets from different countries or regions in the world. They proposed several approaches for redistributing garbage codes, such as expert consultancy, fixed proportional reassignment, using the information about death cause chain, building statistical models, and so on. This paper summarizes and compares the principles, applications and limitation of application scenarios of currently common methods for garbage code redistribution in order to provide some references for improving the accuracy and usefulness of the death cause data in China.

Identification of a large dataset of SNPs in hair-fin anchovy (Setipinna tenuifilis) based on RAD-seq

Hair-fin anchovy (Setipinna tenuifilis) is an economically important fish distributed in the West Indian Ocean and the Northwest Pacific Ocean. In this study, 154 individuals in eight populations of S. tenuifilis were sequenced and 850 million raw reads were obtained using restriction site-associated DNA sequencing (RAD-seq). First, we identified 14 012 044 hypothetical SNP markers. A dataset of 199 903 high-quality SNPs was collected after further screening. These SNPs have a strong ability to test the genetic diversity between the eight populations. The differentiation and genetic law between samples were explored based on SNPs in populations of S. tenuifilis. The results of this study will provide data for protecting the genetic resources of the species.

Exploring factors having an impact on attitudes and motivations towards volunteering in the undergraduate nursing student population - A comparative study of the UK and Ghana

This study explores attitudes and motivations towards volunteering in nursing students in Ghana compared with nursing students in the United Kingdom (UK). Ghana traditionally follows a western model of nurse education, with students studying programmes commensurate in theory and practice, making Ghana a suitable location for a comparative study. We explored similarities and differences in attitudes and motivation towards volunteering to challenge and inform our common place practice towards nursing pedagogy. Ghanaian students displayed positive attitudes towards volunteering, although these did not translate into increased motivation to volunteer while at university. Students reported financial constraints as reasons for not volunteering as did UK students, although Ghanaian students used available resources for daily living expenses, whereas UK students prioritised available resources to pay down student debt. Structured volunteering was absent from both Ghanaian and UK nursing programmes, despite its potential to increase the variety of social groups or situations to which students are exposed, to increase self-confidence and to encourage greater reflection on practice through doing. Structural challenges within countries may provide a better explanation of variation in student motivation towards volunteering, than cross-cultural variation in attitudes towards volunteering between countries.

[Significant Increase in Astigmatism after Cycloplegia in Two Children]

Two cases with high corneal astigmatism and mixed astigmatism were reported. Both cases showed significantly increased astigmatism after cycloplegia. Combined with the patients' refractive error, corneal topography and wavefront aberration changes, the possible causes were analyzed. Aberration changes caused by pupil dilation, corneal astigmatism differences in different diameter ranges, and changes in lens astigmatism before and after cycloplegia may lead to increased astigmatism after cycloplegia. It was found that cycloplegic refraction may not accurately reflect the refractive status in daily life for children with high corneal astigmatism, especially mixed astigmatism. Because children need refractive correction in the state of natural pupil, it is recommended that the cycloplegic refraction result could not be directly used as prescription for such children. The final prescription should be based on the topography and the refraction result under natural pupil.

[The Influence of Short-term Orthokeratology on Tear Film in Adult Myope]

Objective

To study the changes of tear film after short-term overnight orthokeratology wearing in adult myope.

Methods

Fifty adult myope aged 18 to 38 years old were enrolled in this study. The patients wore orthokeratology 6-10 h every night during this study. Data such as non-invasive tear break-up time (NITBUT), fluorescent tear break-up time (FTBUT), lower tear meniscus height (LTMH), corneal fluorescent staining as well as ocular surface disease index (OSDI) questionnaire score were measured at baseline, 1 d, 7 d, 14 d, 30 d and 90 d.

Results

Forty-four subjects completed the follow-up study. Tear break-up time (TBUT) decreased and became stable at 14 d after overnight orthokeratology wearing. LTMH sustained decreased and there was a difference after 90 d overnight wearing （ P<0.05）. Compared with baseline, the grade of corneal staining increased at all time points （ P<0.05）. As for the OSDI score, there was no difference at all time points.

Conclusion

After overnight orthokeratology wearing, tear film stability and tear secretion decreased. Adult myope seems easily to suffer corneal injury after overnight orthokeratology wearing.

[Comparative study on visual fatigue caused by watching liquid crystal display and projection display]

Objective: To explore the effect of different types of visual display terminals (VDT) on visual fatigue. Methods: A total of 68 subjects were enrolled and divided into flat screen group, metal screen group and glass bead screen group. The subjects watched a video in the same environment for 60 minutes. Before and after watching, they were asked to fill in a visual fatigue rating scale and underwent visual function examinations. The blink rate of subjects was recorded during the experiment. Results: After watching the video, for the metal screen, glass bead screen, and flat screen group respectively: (1)The median (interquartile range, IQR) of visual fatigue rating increased significantly (before: 1.0 (1.2), 1.3 (1.6), 0.5 (0.9); after: 2.1 (1.9), 2.1 (1.7), 1.2 (1.0); Z=-4.72, -4.83, -3.75; all P<0.05). (2) The median (IQR) of blink frequency increased significantly (before: 11.5 (10.6), 15.3 (11.9), 7.0 (13.0) times/minute; after: 15.0 (13.0), 17.0 (16.0), 15.0 (12.0) times/minute; Z=-2.64, -2.74, -4.12; all P<0.05). (3) The mean (±standard deviation) of critical flicker fusion frequency (CFF) decreased significantly [before: (35.76±2.98), (35.84±2.79), (35.44±2.21) Hz; after: (35.09±2.78), (34.94±2.67), (34.57±2.33) Hz; t=-2.64, -2.38, -4.12; all P<0.05). (4)The median (IQR) of near point of convergence (NPC) became significantly larger [before: 3.9 (2.6), 4.0 (2.5), 4.3 (2.7) cm; after 5.4 (3.8), 4.8 (2.7), 6.1 (3.9) cm; Z=-3.39, -2.27, -3.36; all P<0.05]. (5)The median of negative relative accommodation (NRA) reduced significantly [before: 2.00 (0.50), 2.00 (0.56), 2.00 (0.25) cm; after 1.75 (0.50), 1.75 (0.25), 1.75 (0.50) cm; Z=-1.98, -2.09, -2.53; all P<0.05]. Meanwhile, no significant changes were found for the positive relative accommodation (PRA), accommodative amplitude, accommodative response, negative relative vergence in all groups after watching the video. The comparisons between the three groups showed that, after watching the video, the participants in the two kinds of projection screen group (the metal and glass bead screen group) had more subjective visual fatigue than those in the flat screen group respectively (Z=-2.09, -2.21; all P<0.05), while there was no significant difference in subjective visual fatigue between the two projection screen groups (P>0.05). In addition, positive fusional vergence recovery point and break point decreased after watching the video in the metal screen and glass bead screen group, respectively (t=4.15, 2.07; all P<0.05). However, no such change was found in the flat screen group. Conclusions: Short-term and long-distance VDT operations have significant effects on visual fatigue, which may be due to the decreased positive convergence ability. VDT operations over projection screens may result in more visual fatigue than LED flat panel display, while the effect of different projection screen types have insignificant influences on visual fatigue. (Chin J Ophthalmol, 2019, 55:595-600).

Decreased expression of gap junction delta-2 (GJD2) messenger RNA and connexin 36 protein in form-deprivation myopia of guinea pigs

BACKGROUND

More than ten genome-wide association studies have identified the significant association between the gap junction delta-2 (GJD2) gene and myopia. However, no functional studies have been performed to confirm that this gene is correlated with myopia. This study aimed to observe how this gene changed in mRNA and protein level in the form-deprivation myopia (FDM) animal model.

METHODS

Four-week-old guinea pigs were randomly divided into two groups: control and FDM groups (n = 12 for each group). The right eyes of the FDM group were covered with opaque hemispherical plastic lenses for 3 weeks. For all the animals, refractive status, axial length (AL), and corneal radius of curvature were measured at baseline and 3 weeks later by streak retinoscope, A-scan ultrasonography, and keratometer, respectively. Retinal GJD2 mRNA expression and connexin 36 (Cx36) levels in FDM and control groups were measured by quantitative real-time PCR and Western blot analyses, respectively. Those results were compared using independent t test, Mann-Whitney U test, or paired t test. A significance level of P < 0.05 was used.

RESULTS

Three weeks later, the FDM group (form-deprived eyes) showed about a myopic shift of approximately -6.75 (-7.94 to -6.31) D, while the control group remained hyperopic with only a shift of -0.50 (-0.75 to 0.25) D (Z = -3.38, P < 0.01). The AL increased by 0.74 (0.61-0.76) and 0.10 (0.05-0.21) mm in FDM and control groups, respectively (Z = -3.37, P < 0.01). The relative mRNA expression of GJD2 in the FDM group decreased 31.58% more than the control group (t = 11.44, P < 0.01). The relative protein expression of CX36 on the retina was lowered by 37.72% in form-deprivation eyes as compared to the controls (t = 17.74, P < 0.01).

CONCLUSION

Both the mRNA expression of GJD2 and Cx36 protein amount were significantly decreased in the retina of FDM guinea pigs. This indicates that Cx36 is involved in FDM development, providing compensating evidence for the results obtained from genome-wide association studies.

Functional significance of stereopsis in professional table-tennis players

BACKGROUND

Stereopsis is the most important part of depth perception, especially in athletic population. At present, there are few studies on how to comprehensively evaluate athletes' stereoscopic function and how the impairment of stereoscopic function affects sports performance.

METHODS

Twenty-two professional table-tennis players from Sichuan Province Team were recruited as player group and 23 age-matched students were recruited as the controls. All subjects were measured the habitual visual acuity, best corrected visual acuity, dominant eye, retinoscopy and three stereo acuity tests. Both groups completed two motor skills tasks: Purdue Pegboard and beads threading with habitual binocular viewing and monocular viewing by covering dominant eye. In addition, the player group was asked to complete a brief questionnaire and catch balls served by the auto table-tennis machine under two viewing conditions.

RESULTS

The player group had better stereo acuity with median values of 60, 25 and 40 arc sec in TNO, Butterfly, and Frisby tests, respectively. There had statistically correlations between stereo acuity and two motor skills tasks. Both the two tasks were statistically significant different between binocular and monocular viewings in both groups. The player group had better performance on Purdue Pegboard task with binocular viewing (16±1.1, P=0.006) compared to the control group, while no statistical difference was found under monocular condition in beads threading task. In player group, the brief questionnaire demonstrated very negative feeling of players under monocular viewing and the number of catching balls had statistically significant difference between binocular (9.9±0.3) and monocular (6.9±1.6) viewings (P<0.001).

CONCLUSIONS

Stereopsis plays an important role in sports performance, the stereo tests combined with Purdue pegboard can be used to evaluate athletes' stereoscopic function comprehensively.

[Effect of concurrent chemoradiotherapy and radiotherapy alone on peripheral myeloid-derived suppressor and T regulatory cells in patients with nasopharyngeal cancer]

Objective: To investigate the percentage of myeloid-derived suppressor cells (MDSC) and T regulatory cells (Treg) in peripheral blood of nasopharyngeal cancer (NPC) patients undergoing concurrent chemoradiotherapy or radiotherapy alone. Methods: Sixty NPC patients who received radiotherapy or concurrent chemoradiotherapy from September 2012 to November 2015 and 20 healthy individuals were included in this study. For the patients, the blood samples were collected at four time points: pre-radiation (Pre-RT), reaching a dose of 40 Gy (RT-40 Gy), finishing radiation (RT-finish) and three months after finishing radiation (3m-post-RT). Flow cytometry was used to evaluate the percentage of Treg (CD4(+) CD25(+) CD127(low/-)) and MDSC (HLA-DR(-)CD11b(+) CD33(+) ) cells in peripheral blood. Results: Treg and MDSC cells were present in peripheral blood lymphocytes of healthy individuals as a percentage of (7.50±1.62)% and (1.08±0.48)%, respectively. The proportions of peripheral Treg cells in patients at Pre-RT, RT-40 Gy, RT-finish and 3m-post-RT time points were (8.42± 1.52)%, (9.10±1.57)%, (8.87±1.56)% and (7.31±1.43)%, respectively, showing a statistically significant difference between Pre-RT and the other groups (P<0.05). At Pre-RT point, the percentage of Treg cells in Stage Ⅲ-Ⅳ patients [(8.63±1.39)%] was higher than that in Stage Ⅰ-Ⅱ [(7.65±1.94)%, P=0.042]. Moreover, the proportions of peripheral MDSC cells in patients at Pre-RT, RT-40 Gy, RT-finish and 3m-post-RT time points were (2.14±1.21)%, (4.08±1.90)%, (3.76±1.31)% and (1.52±0.88)%, respectively. The percentages of MDSC cells at RT-40 Gy and RT-finish points were significantly higher than those at Pre-RT, while the percentage of MDSC cells at 3m-post-RT was significantly lower than those at Pre-RT (P<0.05). At Pre-RT point, the percentage of MDSC cells in Stage Ⅲ-Ⅳ patients [(2.25±1.26)%] was higher than that in Stage Ⅰ-Ⅱ [(1.35±0.66)%, P=0.007]. At RT-finish point, the proportions of MDSC and Treg cells in patients with Ⅲ-Ⅳ grade of radiation induced oral mucositis [(4.41±1.27)% and (9.91±1.23)%] were significantly higher than those in Ⅰ-Ⅱ grade patients [(3.15±1.04)% and (8.41±1.52)%, both of P<0.05]. Conclusions: The proportions of MDSC and Treg cells in initial treated NPC patients are higher than healthy individuals, and they are also associated with the tumor stages. During the concurrent chemoradiotherapy and radiation, the percentage of MDSC and Treg cells is elevated, suggesting a decreased immune activity. The increase of MDSC and Treg cells is related to radiation induced oral mucositis.

[Association between the expression of MMP1 gene and prognosis in head and neck squamous cell carcinoma]

Objective:The aim of this study is to investigate the expression of MMP1 and prognosis in patients with head and neck squamous cell carcinoma (HNSCC), and to identify the potential mechanism of MMP1 in HNSCC. Method:The RNA sequencing data and related clinical data of HNSCC were downloaded from the TCGA public database. The MMP1 gene expression data and corresponding clinical information in the samples were retrospectively analyzed; The data of gene microarray were used to verify the correlation between MMP1 gene and HNSCC. The disease free survival and overall survival of HNSCC were also analyzed; Gene set enrichment analysis was conducted to identify the potential mechanism of MMP1 in HNSCC. Result:Among the 332 HNSCC patients, the expression of MMP1 was significantly associated with lymphatic invasion and tumor grade (P<0.01). The higher the expression level of MMP1 was, the more susceptible the patient was to lymph node metastasis. The data confirmed that the expression of MMP1 in HNSCC was significantly higher than that in normal mucosa (P<0.05); HNSCC of patient in MMP1 high expression group proved to have worse disease free survival and overall survival than in MMP1 low expression group (P<0.05); Gene enrichment analysis indicates that the high expression of MMP1 gene might influence the biological process of tumor though epithelial mesenchymal transition, TGF-β signaling pathway, hypoxia, angiogenesis, Noth signaling pathway, and up-regulation of KRAS gene signaling pathway. Conclusion:The high expression of MMP1 was related with occurrence and development of HNSCC, which can be used as an independent risk factor and has a great clinical significance.

[Motion-in-depth Perception and Static Stereopsis of Patients with Strabismics]

OBJECTIVE

To determine the role of motion-in-depth perception and static stereopsis in strabismics, and factors associated with the perception of motion-in-depth.

METHODS

A total of 84 strabismic patients (including 57 intermittent exotropes, 12 constant exotropes and 15 esotropes) and 16 normal controls were recruited. Binocular fusion ability, static stereopsis and motion-in-depth perception were tested using the computer-generated stereoscopic stimuli. The correlations between these tests were analyzed.

RESULTS

There was a significant correlation between motion-in-depth perception and static stereopsis in strabismics. Only patients with static stereopsis demonstrated the perception of motion-in-depth. A positive correlation was found between motion-in-depth perception thresholds and static stereopsis in intermittent exotropes. All participants in the control group had motion-in-depth perception and static stereopsis. The participants with stereopsis had significantly lower thresholds than those with strabismus (P<0.01). The perception of motion-in-depth varied with the type of strabismus: 87.7% of the intermittent exotropes exhibited motion-in-depth perception, whereas none of the constant strabismics were able to pass the motion-in-depth perception tests. The perception of motion-in-depth was correlated with the presence of binocular fusion.

CONCLUSIONS

Motion-in-depth perception is correlated with static stereopsis in strabismics. The perception of motion-in-depth varies with the type of strabismus: only intermittent exotropes have the perception of motion-in-depth.

Isotope-coded protein label based quantitative proteomic analysis reveals significant up-regulation of apolipoprotein A1 and ovotransferrin in the myopic chick vitreous

This study used isotope-coded protein label (ICPL) quantitative proteomics and bioinformatics analysis to examine changes in vitreous protein content and associated pathways during lens-induced eye growth. First, the vitreous protein profile of normal 7-day old chicks was characterized by nano-liquid chromatography electrospray ionization tandem mass spectrometry. A total of 341 unique proteins were identified. Next, myopia and hyperopia were induced in the same chick by attaching -10D lenses to the right eye and +10D lenses to the left eye, for 3 and 7 days. Protein expression in lens-induced ametropic eyes was analyzed using the ICPL approach coupled to LCMS. Four proteins (cystatin, apolipoprotein A1, ovotransferrin, and purpurin) were significantly up-regulated in the vitreous after 3 days of wearing -10D lenses relative to +10D lens contralateral eyes. The differences in protein expression were less pronounced after 7 days when the eyes approached full compensation. In a different group of chicks, western blot confirmed the up-regulation of apolipoprotein A1 and ovotransferrin in the myopic vitreous relative to both contralateral lens-free eyes and hyperopic eyes in separate animals wearing +10D lenses. Bioinformatics analysis suggested oxidative stress and lipid metabolism as pathways involved in compensated ocular elongation.

[Efficacy of Superior Rectus and Lateral Rectus Muscle Belly Union Surgery for Myopic Strabismus Fixus]

OBJECTIVE

To evaluate the effectiveness of superior rectus (SR) and lateral rectus (LR) union suture without scleral fixation for the treatment of myopic strabismus fixus.

METHODS

A retrospective review was performed on 27 eyes of 16 patients who underwent lateral part of SR and superior part of LR muscle belly union between January 2010 and October 2015. We collected the ocular data including: best corrected visual acuity,axial length,CT or MRI images,orthoptic measurements (by prism test),and eye movements pre- and postoperatively.

RESULTS

The follow up time varied from 3-12 months. All of the patients got satisfactory results except two severe cases. A statistical change of prism test value and eye movement was noticed ( P<0.01). Orthoptic measurements showed that the mean esotropia was improved from (92.50±18.17)Δ preoperatively to (9.19±4.39)Δ postoperatively ( P<0.01). In regards for the vertical deviation,the mean residual hypotropia was (2.38±3.10)Δ postoperatively compared to (21.88±5.74)Δ preoperatively ( P<0.01). At the last follow-up,mean abduction limitation was improved from -3.19±0.62 to -1.15±0.52 ( P<0.01),mean elevation limitation was improved from -2.85±0.82 to -0.78±0.51 ( P<0.01). No special complications were noted.

CONCLUSION

Muscle belly suture of SR and LR was an effective surgery to correct ocluar misalignment and motility in myopic strabismus fixus.

[Research advances on cortical functional and structural deficits of amblyopia]

Previous studies have observed functional deficits in primary visual cortex. With the development of functional magnetic resonance imaging and electrophysiological technique, the research of the striate, extra-striate cortex and higher-order cortical deficit underlying amblyopia reaches a new stage. The neural mechanisms of amblyopia show that anomalous responses exist throughout the visual processing hierarchy, including the functional and structural abnormalities. This review aims to summarize the current knowledge about structural and functional deficits of brain regions associated with amblyopia. (Chin J Ophthalmol, 2017, 53: 392-395).

Post-translational modifications and their applications in eye research (Review)

Gene expression is the process by which genetic information is used for the synthesis of a functional gene product, and ultimately regulates cell function. The increase of biological complexity from genome to proteome is vast, and the post-translational modification (PTM) of proteins contribute to this complexity. The study of protein expression and PTMs has attracted attention in the post‑genomic era. Due to the limited capability of conventional biochemical techniques in the past, large‑scale PTM studies were technically challenging. The introduction of effective protein separation methods, specific PTM purification strategies and advanced mass spectrometers has enabled the global profiling of PTMs and the identification of a targeted PTM within the proteome. The present review provides an overview of current proteomic technologies being applied in eye research, with a particular focus on studies of PTMs in ocular tissues and ocular diseases.

Apoptosis, proliferation, and morphology during vein graft remodeling in rabbits

Neo-intima development and atherosclerosis limit the long-term use of vein grafts for revascularization of ischemic tissues. Recently, studies have confirmed that proliferating cell nuclear antigen (PCNA) plays an important role in cell proliferation. Our research confirmed that 28 days after vein transplantation, PCNA expression increases significantly. Using rabbits, rather than rodents, for a more representative model of human vein grafts, we aimed to establish a time course of changes in cell proliferation and apoptosis using morphometric and immunohistochemical analyses, western blot, terminal deoxynucleotidyl transferase dUTP nick end labeling, and transmission electron microscopy (TEM). The external jugular veins of 42 healthy purebred male New Zealand white rabbits were grafted onto their common carotid arteries. The rabbits were divided into seven groups, with vein grafts being harvested before surgery, and at 1, 3, 7, 14, 28, and 90 days afterwards. The extent of stenosis and apoptosis, PCNA protein levels, and TEM morphology were subsequently examined. Intimal thickness was slightly decreased 1 day following surgery, but then increased continuously until the 90th day. Western blot and immunohistochemistry both indicated lowered PCNA expression on day 1, although levels subsequently increased, peaking at 7 days post-surgery. After surgery, apoptosis was lowest on day 7, and remained low thereafter. TEM revealed signs of apoptosis as vein graft restenosis progressed. Proliferation and apoptosis co-occurred following grafting, indicating that both processes were involved in vein graft remodeling. Apoptosis levels were highest between days 1 and 3 after surgery, whereas proliferation culminated on the 7th day.

Bio-syncretic tweezers actuated by microorganisms: modeling and analysis

Advancements in micro-/nano-technology have led to the development of micro-manipulators. However, some challenges remain; for instance, the efficiency, precision and flexibility of micro-manipulators restrain their applications. This paper proposes a bio-tweezer system to flexibly manipulate micro-objects with bio-actuation via local light-induced high-concentration microorganisms in two different manipulation modes: light-spot induced mode and geometric shape-induced mode. Depending on the shape of micro-objects, either 2-dimensional translation or 1-dimensional rotation can be achieved. Based on the Langevin equation, a mathematical model considering both hydrodynamics and mimicked Brownian motion is proposed to analyze the bio-manipulation performance of the microorganisms; the model was validated by experiments to translate micro-particles in a two-dimensional plane and to rotate a micro-gear structure around its axis. This paper will aid in the development of micro-manipulators and the quantitative understanding of micro-/nano-manipulation actuated by microorganisms.

Short Communication: Molecular cloning and expression pattern of the porcine 5-aminolevulinate synthase 1 (ALAS1) gene and its association with reproductive traits

5-Aminolevulinate synthase 1 (ALAS1) is the first enzyme in the heme biosynthetic pathway and is upregulated in follicular tissue during the early stages of ovulation. In this study, we isolated the complete coding sequence of the porcine ALAS1 gene and its 2-9 intron sequence, identified a single nucleotide polymorphism (SNP; T/C) in intron 9, and developed a PCR-MspI-restriction fragment length polymorphism genotyping assay. Association of the SNP with litter size was assessed in two populations [purebred Large White and the experimental synthetic (DIV) line]. Statistical analysis demonstrated that for total number of piglets born (TNB) in all parities, pigs with the CC genotype had an additional 0.68 and 0.74 piglets compared to the TC and TT animals (P < 0.05) in the DIV line, respectively. Purebred Large White sows inheriting the CC and TC genotypes gave birth to an additional 0.96 and 0.70 piglets compared to the TT animals (P < 0.05) in all parities, respectively. In addition, for TNB in all parities, a significant additive effect of 0.48 ± 0.23 and 0.37 ± 0.17 piglets/ litter was detected in sows of both populations (P < 0.05), respectively. The highest levels of ALAS1 gene expression were observed in isolated ovarian granulosa cells 2 and 12 h after stimulation with pregnant mare serum gonadotropin human chorionic gonadotropin, which represents the time of follicular development and ovulation, respectively. Therefore, the ALAS1 gene was significantly associated with litter size in two populations and could be a useful molecular marker for the selection of increasing litter size in pigs.

Amblyopic-related frontal changes in an orientation discrimination task: a research of P3a event-related potentials in anisometropic amblyopia

BACKGROUND

Amblyopic deficits in the primary and secondary visual cortex have been demonstrated broadly. However, the cognitive process at late stage originating in higher brain area in amblyopes hasn't been studied yet. The aim of this study was to investigate the late cognitive process at the frontal lobe in anisometropic amblyopes of a distinct degree, using visual event-related potential (ERP) techniques.

METHODS

Thirteen severe anisometropic amblyopes, 14 mild-to-moderate anisometropic amblyopes, and 13 control subjects participated in this study. Oddball paradigm (three stimuli: target, novel, and non-target stimuli) of low spatial frequency (1 cycle per degree, CPD) was used to elicit brain ERP waves. Reaction time, accuracy, latency, and amplitude of P3a waves evoked by novel stimuli at Fz electrode (the central electrode at frontal lobe), were analyzed statistically.

RESULTS

Neither accuracy nor reaction time showed significant difference among the three groups. The latency of N200 wave showed no significant difference. The latency of P3a wave was delayed in the amblyopes compared with healthy controls, but there was no significant difference between severe and mild-to-moderate amblyopes. P3a amplitude in mild-to-moderate amblyopes was significantly higher than in controls and severe amblyopes.

CONCLUSIONS

Our findings indicated that the cognitive process in anisometropic amblyopes was impaired, and the compensative effect of P3a amplitude was shown in mild-to-moderate amblyopes. P3a visual ERP could become a useful tool to investigate cognitive processing in amblyopes. Hippokratia 2016, 20(1): 60-66.