[The role of peripheral retinal defocus in myopia progression].

The increasing incidence of myopia has become a global public health concern. Exploring the mechanisms underlying the onset and progression of myopia is crucial for prevention and control. This paper reviews the role of peripheral retinal defocus mechanisms in the development of myopia, with particular emphasis on the interaction between accommodation lag and peripheral retinal defocus, as well as the impact of optical intervention on myopia control effectiveness. In recent years, researchers have developed various optical tools for myopia prevention and control based on the peripheral retinal defocus theory, such as peripheral defocus spectacle lenses, orthokeratology lenses, and peripheral defocus soft contact lenses. This paper aims to provide clinicians with the latest research findings to deepen their understanding of the mechanisms involved in myopia development and to guide the future development and clinical application of myopia prevention and control products.

[Clinical and genetic analysis of tyrosine hydroxylase deficiency of six cases].

The clinical and molecular genetic data of 6 patients with genetically confirmed tyrosine hydroxylase deficiency(THD) diagnosed in Department of Neurology, Qilu Hospital of Shandong University from March 2017 to February 2022 were retrospectively collected and analyzed. The 6 patients were from 5 families. Among them, 5 patients had persistent or paroxysmal abnormal walking posture, 4 patients had dystonia of head and face, including spasm of perioral and oculopharyngeal muscles, hyperactivity, and binocular upvision, 4 patients showed obvious morning light and evening heavy phenomenon, 2 patients had postural tremor of limbs, 2 patients had psychomotor retardation from childhood, 1 patient only had limb and cervical muscle weakness, 1 patient had epileptic seizures. Of the 6 patients, only 1 was adult-onset, and the rest were child-onset. Four patients had good response to low-dose dopa preparation, 2 patients from the same family had poor response to dopamine treatment, requiring extremely low dose initiation and multi-frequency titration treatment. However, the long-term treatment effect was poor with obvious abnormalities. Gene testing of 5 families revealed 8 mutations in the TH gene, with c.698G>A (p.R233H) being the hot spot mutation site. The clinical manifestations of THD are complex. Besides paroxysmal or persistent dystonia, it can also be accompanied by eye movement crisis, muscle weakness, epilepsy, and delayed mental and motor development. Most patients respond well to low-dose dopamine preparations, but a small number of patients require titration treatment with extremely low-dose dopamine preparations, and the long-term effect is not satisfactory.

[The mid-term effect of corneal collagen cross-linking for progressive keratoconus and the changes in rigid gas permeable contact lens fitting parameters].

Objective: To investigate the effect of corneal collagen cross-linking (CXL) for progressive keratoconus and to evaluate changes in the parameters of rigid gas permeable contact lens (RGPCL) fitting after surgery. Methods: It was a prospective cohort study. Fifty-three eyes of 41 keratoconus patients received accelerated CXL in Qingdao Eye Hospital of Shandong First Medical University from May to December 2018. There were 31 males and 10 females, aged (20.46±4.15) years. According to the corneal thickness, de-epithelial CXL (33 eyes) or trans-epithelial CXL (20 eyes) was performed. The best spectacle-corrected visual acuity, refractive power and the thinnest corneal thickness at baseline and at 6 weeks were compared. Corneal topography was performed at baseline and at 6 weeks, 3, 6 and 12 months postoperatively. Rose K RGPCLs were used before and 6 weeks after surgery, and the fitting status was monitored until 12 months after surgery. The t test was performed to analyze the difference before and after the operation. Results: The best spectacle-corrected visual acuity, refractive power, and the thinnest corneal thickness were not significantly changed over 6 weeks of follow-up, but the Kf, Ks and Kmax values were significantly increased in all patients (all P<0.05). In the de-epithelial group, the Kmax values before the operation, at 3, 6 and 12 months after the operation were (55.00±5.51) diopters (D), (54.73±5.34) D, (54.58±6.15) D and (54.20±5.49) D, respectively, and the decrease at 12 months was significant [(0.80±2.05) D; t=2.25, P=0.001]. In the trans-epithelial group, the Kmax values were (59.43±8.98) D, (57.97±8.79) D, (58.19±8.37) D and (56.94±7.19) D at the four time points, respectively, and the decreases at 3, 6 and 12 months were all significant [(1.46±2.09) D, (1.25±1.82) D, (2.49±3.64) D; t=3.12, 3.06, 3.50; P=0.006, 0.006, 0.007]. The best RGPCL-corrected visual acuity, the diameter and the average diopters of RGPCLs showed no significant change in both groups. The RGPCL base curve decreased by 0.07 mm in the de-epithelial group and by 0.13 mm in the trans-epithelial group (both P<0.05). The design of edge lifting was used in 10 eyes postoperatively in the de-epithelial group compared with 8 eyes preoperatively, and in 4 eyes postopratively in the trans-epithelial group compared with 7 eyes preoperatively. The number of eyes using the toric peripheral design of the lens was increased to 3 compared with 2 preoperatively in the de-epithelial group and from 1 to 4 in the trans-epithelial group. The acceptance rate of RGPCL fitting in both groups increased at 6 and 12 months after surgery compared to 6 weeks after surgery. Conclusions: The corneal curvature became steep slightly at 6 weeks after CXL and gradually recovered and flattened. The Kmax in the trans-epithelial group decreased earlier and more than that in the de-epithelial group. The base curve of the RGPCLs was slightly reduced after 6 weeks, and the toric peripheral design was increasingly needed, but the requirement for the design of the lifted edge was different between the two groups. A good RGPCL fitting can be achieved within 1 year after CXL.

Follow-up management strategy for patients undergoing peritoneal dialysis during novel coronavirus pneumonia epidemic.

OBJECTIVE: The study aimed to explore the best follow-up management strategy for patients undergoing peritoneal dialysis (PD) during the novel coronavirus pneumonia (NCP) epidemic. PATIENTS AND METHODS: Patients undergoing PD who were followed up during the NCP epidemic by our hospital were enrolled in this study. Because of the need to control the epidemic, a follow-up system was established during the epidemic period, with WeChat, QQ, and the telephone as the main methods of communication. Outpatient and emergency follow-ups were carried out to ensure the safety of dialysis and the prevention and control of the epidemic. The follow-up strategy included response measures related to the epidemic situation, prevention of peritonitis related to PD, water and salt control, exercise guidance, and psychological care. According to the patient's condition, the appointment system was implemented, with one consulting room and one process for each patient. The emergency patients were isolated in accordance with the epidemic situation. RESULTS: Since January 2020, among the 580 patients undergoing PD who were followed up in our department and their families, none had NCP infection. During the epidemic period, the standard hemoglobin level and the inpatient rate decreased. Complications related to PD, such as peritonitis, cardiovascular complications caused by volume overload, and pulmonary infection, did not significantly increase, and the withdrawal rate and mortality rate decreased compared with those in the same period last year. CONCLUSIONS: The patient follow-up strategy during the epidemic period had a significant positive effect on preventing and controlling the epidemic. Furthermore, during the epidemic period, encouraging patients and caregivers to pay attention to protection at home, avoid going out, strengthen self-management, and other measures were beneficial to the control of kidney disease itself, which is worth promoting. The close relationship between doctors and patients during the epidemic had a positive effect on the occurrence of complications related to patients undergoing PD.

MicroRNA-206 inhibits tumor metastasis of nasopharyngeal carcinoma through targeting G6PD.

Nasopharyngeal carcinoma (NPC) is a main type of otolaryngological malignancy. In many cancers, miR-206 functions as a tumor suppressor, suppressing cell proliferation, migration and invasion. The purpose of this study was to explore how miR-206 worked on cell metastasis in NPC. The mRNA levels of miR-206 and G6PD were determined in NPC tissues and cell lines by RT-qPCR and Western blot. Transwell assay was applied to evaluate the migratory and invasive capacities. Dual luciferase reporter assay was employed to confirm that miR-206 mediated the expression of G6PD in C666-1 cells. In this study, miR- 206 was downregulated, whereas G6PD was upregulated in NPC tissues and cell lines. In addition, G6PD was identified as a direct target gene of miR-206 in C666-1 cells. The expression of G6PD was mediated by miR-206, which could partially reverse the inhibitory effects of miR-206 on the migration, invasion and EMT in C666-1 cells. In conclusion, miR-206 regulated the migratory, invasive and EMT abilities through directly targeting the 3'-UTR of G6PD mRNA in C666-1 cells. The newly identified miR-206/G6PD axis provides novel insight into the pathogenesis of nasopharyngeal carcinoma.

[Clinical research on robot-assisted percutaneous pelvic and acetabular screws surgery].

OBJECTIVE: To evaluate the security and efficiency of a surgical robotic assisted percutaneous screw fixation for the treatment of pelvic and acetabular fractures. METHODS: In the study, 12 patients with pelvic and acetabular fractures who were treated in Beijing Jishuitan Hospital from January to April in 2016 were involved in this research. The research subjects were randomly divided into two groups: the experimental group and the control group. Robotic-assisted percutaneous sacroiliac screw internal fixations were performed under the guidance of fluoroscopy navigation in the experimental group; in the control group, doctors operated manually guided by fluoroscopy. Statistical analysis was performed on the total operation time, the intraoperative fluoroscopy time, the adjustment numbers of intraoperative guide wires, the excellent rate of screw placement and the incidence of adverse events in order to evaluate the security and efficiency of a surgical robotic assisted percutaneous screw fixation for the treatment of pelvic and acetabular fractures. RESULTS: Eleven screws were placed in 7 patients from the experimental group, while 7 screws were placed in 5 patients from the control group in total. All the screw placement positions were satisfactory according to postoperative CT images. The excellent rates of screw placement position were 100% in both groups. However, the P value was 0.016 based on the comparison between the screws' distribution in the two groups which meant that the screw distribution of the experimental group was better than that of the control group. The average fluoroscopy time needed for screw insertion was (7.36±2.63) s in the experimental group while (41.80±13.99) s in the control group (P<0.001). This suggested that the difference between the two groups had statistical significances. Intra-operative fluoroscopy time of the experimental group was significantly smaller than that of the control group. The number of the average screw adjustment was (0.36±0.48) times in the experimental group while (9.00±3.06) times in the control group (P=0.003). This suggested that the difference of the number of the guide needle adjustment between the two groups had statistical significances, and the number of the experimental group was smaller than that of the control group. The average operation time was (43.86±49.06) min in the experimental group while only (29.00±12.14) min were needed in the control group (P=0.528). This suggested that the difference between the two groups had no statistical significance. That is, the total operation time of the two groups was equal. All the screws were in satisfactory positions according to validation results of CT scans. No complications such as screw breaking out the bone cortex and entering into the knee joint cavity, wound infection occurred. CONCLUSION: Surgical robots are suitable for robot-assisted percutaneous screw fixation in pelvic and acetabular fractures. Robot-assisted treatment of pelvic and acetabular fractures has significant advantages over manual operations including high accuracy, small perspective radiation, safety and efficiency.

Characteristic element of matrix attachment region mediates vector attachment and enhances nerve growth factor expression in Chinese hamster ovary cells.

Preliminary studies have suggested that a characteristic element of the matrix attachment region (MAR) in human interferon-ß mediates the adhesion of vectors to Chinese hamster ovary (CHO) cells. In this study, we investigated if vector adhesion increased nerve growth factor (NGF) expression in CHO cells. The MAR characteristic element sequence of human interferon-ß was inserted into the multiple-cloning site of the pEGFP-C1 vector. The target NGF gene was inserted upstream of the MAR characteristic element sequence to construct the MAR/NGF expression vector. The recombinant plasmid was transfected into CHO cells and stable monoclonal cells were selected using G418. NGF mRNA and protein expression was detected by reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. Plasmid reduction experiments were used to determine the state of transfected plasmid in mammalian cells. The insertion of MAR into the vector increased NGF expression levels in CHO cells (1.93- fold) compared to the control. The recombinant plasmid expressing the MAR sequence was digested into a linear space vector. The inserted MAR and NGF sequences were consistent with those inserted into the plasmid before recombination. Therefore, we concluded that the MAR characteristic element mediates vector adhesion to CHO cells and enhances the stability and efficiency of the target gene expression.

Regulating effects of insertion direction of matrix attachment regions on transgenic expression in stably transformed Chinese hamster ovary cells.

We investigated the effects of different directions of insertion of matrix attachment region (MAR) sequences on transgenic expression in stably transformed Chinese hamster ovary (CHO) cells. The MAR sequences were inserted in forward or reverse directions into the expression vectors, and transfected into CHO cells. The expression of the chloramphenicol acetyltransferase (CAT) reporter gene and the relative copy numbers of the CAT gene were analyzed. The CAT gene expression levels in the vector with the MAR sequence inserted in the forward or reverse directions increased compared with expression without the MAR sequence. The relative copy numbers of the CAT gene with MAR sequenced vectors inserted in the reverse and forward directions were lower, than in the control group. The direction of insertion of MAR sequences had no significant effect on expression levels. The expression levels were not proportional to the copy numbers of the gene.

Association of SIRT2 gene polymorphisms with body measurement and growth traits of Qinchuan cattle.

Silent information regulator 2 (SIRT2), a member of the Sirtuin family of class III nicotinamide adenine dinucleotide-dependent protein deacetylases, plays an important role in senescence, metabolism, and apoptosis. This study was conducted to detect potential polymorphisms of the bovine SIRT2 gene and explore their relationships with meat quality and body measurement traits (BMTs) in Qinchuan cattle. Four single nucleotide polymorphisms (A7445G, C7711T, G17937A, and G20937A) in the fourth intron, fourth exon, ninth exon, and twelfth exon of the SIRT2 gene, respectively, were identified according to the sequencing results of 520 individuals of a Qinchuan cattle population. The genotypic distributions of both A7445G and G20937A were in agreement with the Hardy-Weinberg equilibrium (P < 0.05), whereas the other two mutations were not (0.05 < P < 0.01), based on the X(2) test. Association analysis indicated that the four loci were significantly correlated with several BMTs and meat quality traits. When in combination, the H1H1 (AA-CC-GG-CC) diplotypes showed better BMT and meat quality traits than those by other combinations. Collectively, the results show that SIRT2 is involved in the regulation of the growth and meat quality of cattle, suggesting that the SIRT2 gene may be a candidate gene for marker-assisted selection in the development of future breeding programs for Qinchuan cattle.

Granulocyte colony-stimulating factor attenuates chronic neuroinflammation in the brain of amyloid precursor protein transgenic mice: an Alzheimer's disease mouse model.

Recent evidence suggests that inflammatory mechanisms contribute significantly to the progression of Alzheimer's disease. Granulocyte colony-stimulating factor (G-CSF) is an anti-inflammatory immunomodulator, but the mechanism of its anti-inflammatory effect is unclear. This study was designed to investigate whether G-CSF could inhibit inflammation in a mouse model of Alzheimer's disease through an α7 nicotinic acetylcholine receptor (α7 nAChR) pathway. Mice transgenic for the V171I mutant amyloid precursor protein (APP) were injected subcutaneously with G-CSF 50 µg/kg per day or phosphate-buffered saline (PBS; control group) for 7 days, and wild-type C57/BL6 mice were injected with PBS daily for 7 days. Mice were killed on days 7, 14 and 28 after treatment began. Levels of α7 nAChR protein were significantly increased and levels of interleukin-1ß, tumour necrosis factor-α and nuclear factor-κB (NF-κB) protein were significantly decreased in the brain of APP transgenic mice in response to G-CSF. Levels of α7 nAChR protein correlated negatively with NF-κB levels. It is concluded that G-CSF might attenuate inflammation by down-regulating NF-κB and up-regulating α7 nAChR in the brain of APP transgenic mice, indicating a potential new therapeutic approach to Alzheimer's disease.

Activated beta-catenin induces myogenesis and inhibits adipogenesis in BM-derived mesenchymal stromal cells.

BACKGROUND: Mesenchymal stromal cells (MSC) have been thought to be attractive candidates for the treatment of degenerative muscle diseases. However, little is known about the molecular mechanisms governing the myogenic differentiation in MSC. As the Wnt signaling pathway has been associated with myogenesis in embryogenesis and post-natal muscle regeneration, we hypothesized that the Wnt signaling pathway may be involved in governing the myogenic differentiation in MSC. METHODS: Primary MSC were isolated from Sprague-Dawley rats and expanded in proliferation medium. The rMSC were transfected with a constitutively active hbeta-catenin (S37A) plasmid or control vector by Lipofectamine followed by G418 selection. The transfected rMSC were grown to 80% confluence and then cultured in myogenic or adipogenic differentiation medium. Cells were characterized by light microscopy, immunofluorescence and RT-PCR at different time points after myogenic or adipogenic introduction. RESULTS: Ectopic expression of activated beta-catenin located primarily in the nucleus and activated transcription in rMSC. Overexpression of stabilized beta-catenin induced 27.1 +/- 3.91% rMSC forming long multinucleated cells expressing MyoD, myogenin, desmin and myosin heavy chain (MHC) via evoking the expression of skeletal muscle-specific transcription factors. In addition, overexpression of activated beta-catenin inhibited the adipogenic differentiation in rMSC through down-regulated expressions of C/EBPalpha and PPARgamma. DISCUSSION: To our knowledge, this is the first evidence that activated beta-catenin can induce myogenic differentiation in rMSC. The ability of stabilized beta-catenin to induce myogenic differentiation in rMSC may allow for its therapeutic application.

Human mesenchymal stromal cells ameliorate the phenotype of SOD1-G93A ALS mice.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a progressive, lethal, neurodegenerative disease, currently without any effective therapy. Multiple advantages make mesenchymal stromal cells (MSC) a good candidate for cellular therapy in many intractable diseases such as stroke and brain injury. Until now, no irrefutable evidence exists regarding the outcome of MSC transplantation in the mouse model of ALS. The present study was designed to investigate the therapeutic potential of human MSC (hMSC) in the mouse model of ALS (SOD1-G93A mice). METHODS: hMSC were isolated from iliac crest aspirates from healthy donors and kept in cell cultures. hMSC of the fifth passage were delivered intravenously into irradiated pre-symptomatic SOD1-G93A mice. Therapeutic effects were analyzed by survival analysis, rotarod test, motor neuron count in spinal cord and electrophysiology. The engraftment and in vivo differentiation of hMSC were examined in the brain and spinal cord of hMSC-transplanted mice. RESULTS: After intravenous injection into irradiated pre-symptomatic SOD1-G93A mice, hMSC survived more than 20 weeks in recipient mice, migrated into the parenchyma of brain and spinal cord and showed neuroglia differentiation. Moreover, hMSC-transplanted mice showed significantly delayed disease onset (14 days), increased lifespan (18 days) and delayed disease progression compared with untreated mice. DISCUSSION: Our data document the positive effects of hMSC transplantation in the mouse model of ALS. It may signify the potential use of hMSC in treatment of ALS.