Topoisomerase IIA in adult NSCs regulates SVZ neurogenesis by transcriptional activation of Usp37.

Topoisomerase IIA (TOP2a) has traditionally been known as an important nuclear enzyme that resolves entanglements and relieves torsional stress of DNA double strands. However, its function in genomic transcriptional regulation remains largely unknown, especially during adult neurogenesis. Here, we show that TOP2a is preferentially expressed in neurogenic niches in the brain of adult mice, such as the subventricular zone (SVZ). Conditional knockout of Top2a in adult neural stem cells (NSCs) of the SVZ significantly inhibits their self-renewal and proliferation, and ultimately reduces neurogenesis. To gain insight into the molecular mechanisms by which TOP2a regulates adult NSCs, we perform RNA-sequencing (RNA-Seq) plus chromatin immunoprecipitation sequencing (ChIP-Seq) and identify ubiquitin-specific protease 37 (Usp37) as a direct TOP2a target gene. Importantly, overexpression of Usp37 is sufficient to rescue the impaired self-renewal ability of adult NSCs caused by Top2a knockdown. Taken together, this proof-of-principle study illustrates a TOP2a/Usp37-mediated novel molecular mechanism in adult neurogenesis, which will significantly expand our understanding of the function of topoisomerase in the adult brain.

Clinical features and treatment options for pediatric adrenal incidentalomas: a retrospective single center study.

BACKGROUND: The aim of this study was to investigate the clinical features and treatment options for pediatric adrenal incidentalomas(AIs) to guide the diagnosis and treatment of these tumors. METHODS: The clinical data of AI patients admitted to our hospital between December 2016 and December 2022 were collected and retrospectively analyzed. All patients were divided into neonatal and nonneonatal groups according to their age at the time of the initial consultation. RESULTS: In the neonatal group, 13 patients were observed and followed up, and the masses completely disappeared in 8 patients and were significantly reduced in size in 5 patients compared with the previous findings. Four patients ultimately underwent surgery, and the postoperative pathological diagnosis was neuroblastoma in three patients and teratoma in one patient. In the nonneonatal group, there were 18 cases of benign tumors, including 9 cases of ganglioneuroma, 2 cases of adrenocortical adenoma, 2 cases of adrenal cyst, 2 cases of teratoma, 1 case of pheochromocytoma, 1 case of nerve sheath tumor, and 1 case of adrenal hemorrhage; and 20 cases of malignant tumors, including 10 cases of neuroblastoma, 9 cases of ganglioneuroblastoma, and 1 case of adrenocortical carcinoma. CONCLUSIONS: Neuroblastoma is the most common type of nonneonatal AI, and detailed laboratory investigations and imaging studies are recommended for aggressive evaluation and treatment in this population. The rate of spontaneous regression of AI is high in neonates, and close observation is feasible if the tumor is small, confined to the adrenal gland and has no distant metastasis.

Eye growth pattern of myopic children wearing spectacle lenses with aspherical lenslets compared with non-myopic children.

INTRODUCTION: To evaluate eye growth of children wearing spectacle lenses with highly aspherical lenslets (HAL), slightly aspherical lenslets (SAL) and single-vision lenses (SVL) compared to eye growth patterns in non-myopes in Wenzhou, China. METHODS: The randomised trial had 170 myopic children (aged 8-13 years) randomly assigned to the HAL, SAL or SVL group. Normal eye growth was examined using 700 non-myopic schoolchildren (aged 7-9 years) in the Wenzhou Medical University-Essilor Progression and Onset of Myopia (WEPrOM) cohort study using logistic function models. Slow, normal and fast eye growth was defined as range of values <25th, 25th-75th and >75th percentiles, respectively. RESULTS: The predicted upper limits of slow eye growth (25th percentile) among non-myopes aged 7-10 years and 11-13 years were 0.20-0.13 and 0.08-0.01 mm (after 2-year period; 0.37-0.33 and 0.29-0.14 mm), respectively, while the upper limits of normal eye growth (75th percentile) were 0.32-0.31 and 0.28-0.10 mm (after 2-year period; 0.58-0.55 and 0.50-0.24 mm), respectively. The 2-year trial had 157 children, 96 of whom wore their lenses full time (everyday ≥12 h/day). The mean 2-year axial length change for HAL, SAL and SVL was 0.34, 0.51 and 0.69 mm (0.28, 0.46 and 0.69 mm in full-time wear), respectively. Slow eye growth was found in 35%, 17% and 2% (44%, 29% and 3% in full-time wear); normal eye growth in 35%, 26% and 12% (44%, 32% and 9% in full-time wear) and fast eye growth in 30%, 57% and 86% (12%, 39% and 88% in full-time wear), respectively (p < 0.001). CONCLUSIONS: The eye growth pattern in approximately 90% wearing HAL full time (compared with about 10% wearing SVL full time) was similar or slower than that of non-myopic children both after 1- and 2-year periods.

Identification and characterization of sex-dependent gene expression profile in glioblastoma.

Glioblastoma (GBM) is the most lethal primary tumor in the human brain and lacks favorable treatment options. Sex differences in the outcome of GBM are broadly acknowledged, but the underlying molecular mechanisms remain largely unknown. To identify the sex-dependent critical genes in the progression of GBM, raw data from several microarray datasets with the same array platform were downloaded from the Gene Expression Omnibus (GEO) database. These datasets included tumorous and normal tissue from patients with GBM and crucial sex features. Then, the differentially expressed genes (DEGs) in female and male tumors were identified via bioinformatics analysis, respectively. Functional signatures of the identified DEGs were further annotated by Gene Ontology (GO) and pathway enrichment analyses. Venn diagram and functional protein-protein interaction (PPI) network analyses were performed to screen out the sex-specific DEGs. Survival analysis of patients with differences in the expression level of selected genes was then carried out using the data from The Cancer Genome Atlas (TCGA). Here, we showed that ECT2, AURKA, TYMS, CDK1, NCAPH, CENPU, OIP5, KIF14, ASPM, FBXO5, SGOL2, CASC5, SHCBP1, FN1, LOX, IGFBP3, CSPG4, and CD44 were enriched in female tumor samples, whereas TNFSF13B, CXCL10, CXCL8, CXCR4, TLR2, CCL2, and FCGR2A were enriched in male tumor samples. Among these key genes, interestingly, ECT2 was associated with increased an survival rate for female patients, whileTNFSF13B could be regarded as a potential marker of poor prognosis in male patients. These results suggested that sex differences in patients may be attributed to the heterogeneous gene activity, which might influence the oncogenesis and the outcomes of GBM.

[Biological characteristics and functions of NG2-glia].

NG2-glia are a major type of glial cells that are widely distributed in the central nervous system (CNS). Under physiological conditions, they mainly differentiate into oligodendrocytes and contribute to the myelination of axons, so they are generally called oligodendrocyte progenitor cells. Emerging evidence suggests that NG2-glia not only act as the precursors of oligodendrocytes but also possess many other biological properties and functions. For example, NG2-glia can form synapse with neurons and participate in energy metabolism and immune regulation. Under pathological conditions, NG2-glia can also differentiate into astrocytes, Schwann cells and even neurons, which are involved in CNS injury and repair. Therefore, a deeper understanding of the biological characteristics and functions of NG2-glia under physiological and pathological conditions will be helpful for the treatment of CNS injury and disease. This article reviews the recent advances in the biological characteristics and functions of NG2-glia.

Conditional ablation of reactive astrocytes to dissect their roles in spinal cord injury and repair.

Astrocytes become reactive in response to spinal cord injury (SCI) and ultimately form a histologically apparent glial scar at the lesion site. It is controversial whether astrocytic scar is detrimental or beneficial to the axonal regeneration and SCI repair. Therefore, much effort has focused on understanding the functions of reactive astrocytes. Here, we used a lentivirus-mediated herpes simplex thymidine kinase/ganciclovir (HSVtk/GCV) system to selectively kill scar-forming reactive proliferating astrocytes. The suicide gene expression was regulated by human glial fibrillary acidic protein (hGFAP) promoter, which is active primarily in astrocytes. Conditional ablation of reactive astrocytes in a mouse SCI model with crush injury impeded glial scar formation and resulted in widespread infiltration of inflammatory cells, increased neuronal loss, and severe tissue degeneration, which ultimately led to the failure of spontaneous functional recovery. These results suggest that reactive proliferating astrocytes play key roles in the healing process after SCI, shedding light on the potential benefit for the repair after central nervous system (CNS) injury.

Anterior Segment Biometry of the Accommodating Intraocular Lens and its Relationship With the Amplitude of Accommodation.

OBJECTIVES: To evaluate the anterior segment biometry of the Tetraflex accommodating intraocular lens (AIOL) and the contribution of forward movement to the amplitude of accommodation (AMP). METHODS: Patients who underwent phacoemulsification with implantation of Tetraflex AIOLs and control nonaccommodating intraocular lenses were imaged by custom-built, long scan depth spectral-domain optical coherence tomography at relaxed and maximal accommodative states. Anterior segment biometry was performed and correlated with the clinical manifestation including AMP. RESULTS: Patients in the Tetraflex group showed better distance-corrected near visual acuity (logMAR 0.43±0.10 vs. logMAR 0.51±0.10, P<0.05) and greater AMP (1.99±0.58 diopters [D] vs. 1.59±0.45 D, P<0.05) compared with the control group. The measurement of the postoperative anterior chamber depth (ACD) during accommodation showed a forward movement of the AIOLs in 16 eyes (69.6%). Compared with the control group, a greater proportion of cases in the Tetraflex group experienced forward movement (χ test, P<0.001). The AMP in the AIOL group negatively correlated with changes in postoperative ACD during accommodation (r=-0.47, P<0.05), whereas AMP in the control group negatively correlated with postoperative pupil diameter (r=-0.57, P<0.05). CONCLUSIONS: The Tetraflex AIOLs seemed to have a tendency for forward movement; however, the slight forward axial shifts of the Tetraflex AIOL during natural accommodation may not produce a clinically relevant change in optical power.

High-efficiency secretory expression of human neutrophil gelatinase-associated lipocalin from mammalian cell lines with human serum albumin signal peptide.

Human neutrophil gelatinase associated lipocalin (NGAL) is a secretory glycoprotein initially isolated from neutrophils. It is thought to be involved in the incidence and development of immunological diseases and cancers. Urinary and serum levels of NGAL have been investigated as a new biomarker of acute kidney injury (AKI), for an earlier and more accurate detection method than with creatinine level. However, expressing high-quality recombinant NGAL is difficult both in Escherichia coli and mammalian cells for the low yield. Here, we cloned and fused NGAL to the C-terminus of signal peptides of human NGAL, human interleukin-2 (IL2), gaussia luciferase (Gluc), human serum albumin preproprotein (HSA) or an hidden Markov model-generated signal sequence (HMM38) respectively for transient expression in Expi293F suspension cells to screen for their ability to improve the secretory expression of recombinant NGAL. The best results were obtained with signal peptide derived from HSA. The secretory recombinant protein could react specifically with NGAL antibody. For scaled production, we used HSA signal peptide to establish stable Chinese hamster ovary cell lines. Then we developed a convenient colony-selection system to select high-expression, stable cell lines. Moreover, we purified the NGAL with Ni-Sepharose column. The recombinant human NGAL displayed full biological activity. We provide a method to enhance the secretory expression of recombinant human NGAL by using the HSA signal peptide and produce the glycoprotein in mammalian cells.

[Structural, mechanistic and functional insights into topoisomerase II].

Topoisomerases are nuclear enzymes that regulate the overwinding or underwinding of DNA helix during replication, transcription, recombination, repair, and chromatin remodeling. These enzymes perform topological transformations by providing a transient DNA break, through which the unique problems of DNA entanglement that occur owing to unwinding and rewinding of the DNA helix can be resolved. In mammals, topoisomerases are classified into two types, type I topoisomerase (Top1) and type II topoisomerase (Top2), depending on the number of strands cut in one round of action. Top1 induces single-strand breaks in DNA, and Top2 induces double-strand breaks. In cells from vertebrate species, there are two forms of Top2, designated alpha and beta. Top2α is involved in the cellular proliferation and pluripotency, while Top2ß plays key roles in neurodevelopment. In this review, we cover recent advances in structural, mechanistic and functional insights into Top2.

Protective effects of astaxanthin against ischemia/reperfusion induced renal injury in mice.

Astaxanthin (ATX) is a powerful antioxidant that occurs naturally in a wide variety of living organisms. Previous studies have shown that ATX has effects of eliminating oxygen free radicals and can protect organs from ischemia/reperfusion (IR) induced injury. The present study was designed to further investigate the protective effects of ATX on oxidative stress induced toxicity in tubular epithelial cells and on IR induced renal injury in mice. ATX, at a concentration of 250 nM, attenuated 100 µM H2O2-inudced viability decrease of tubular epithelial cells. In vivo, ATX preserved renal function 12 h or 24 h post IR. Pretreatment of ATX via oral gavage for 14 consecutive days prior to IR dramatically prevented IR induced histological damage 24 h post IR. Histological results showed that the pathohistological score, number of apoptotic cells, and the expression of α-smooth muscle actin were significantly decreased by pretreatment of ATX. In addition, oxidative stress and inflammation in kidney samples were significantly reduced by ATX 24 h post IR. Taken together, the current study suggests that pretreatment of ATX is effective in preserving renal function and histology via antioxidant activity.

Neuroprotective effects of nitidine against traumatic CNS injury via inhibiting microglia activation.

Glial cell response to injury has been well documented in the pathogenesis after traumatic brain injury (TBI) and spinal cord injury (SCI). Although microglia, the resident macrophages in the central nervous system (CNS), are responsible for clearing debris and toxic substances, excessive activation of these cells will lead to exacerbated secondary damage by releasing a variety of inflammatory and cytotoxic mediators and ultimately influence the subsequent repair after CNS injury. In fact, inhibition of microgliosis represents a therapeutic strategy for CNS trauma. We here showed that nitidine, a benzophenanthridine alkaloid, restricted reactive microgliosis and promoted CNS repair after traumatic injury. Nitidine was shown to prevent cultured microglia from LPS-induced reactive activation by regulation of ERK and NF-κB signaling pathway. Furthermore, the nitidine-mediated inhibition of microgliosis was also shown in injured brain and spinal cord, which significantly increased neuronal survival and decreased neural tissue damage after injury. Importantly, behavioral analysis revealed that nitidine-treated mice with SCI had improved functional recovery as assessed by Basso Mouse Scale and swimming test. Together, these findings indicated that nitidine increased CNS tissue sparing and improved functional recovery by attenuating reactive microgliosis, suggestive of the potential therapeutic benefit for CNS injury.

Corneal reshaping and wavefront aberrations during overnight orthokeratology.

PURPOSE: To investigate changes of corneal thickness at the vertical and horizontal meridians and of wavefront aberrations (WA) over a 30-day period of overnight myopia orthokeratology (OK) lens wear. METHODS: Sixteen subjects (11 women, 5 men, 26.3±3.2 years) were enrolled and fitted for OK lenses. Long scan depth optical coherence tomography was used to measure corneal thickness profiles at both horizontal and vertical meridians at baseline and on days 1, 7, and 30 days. Corneal and ocular WA of a 6-mm pupil were measured and the root-mean-square (RMS) of the astigmatism, coma, spherical aberration (SA), and total higher-order aberrations (HOAs) were determined. RESULTS: During the 30-day period, the central cornea thinned in the horizontal and vertical meridians, whereas corneal thickening occurred in the temporal, nasal, and inferior mid-peripheries. In contrast, the cornea thinned in the mid-peripheral superior. There were significant increases in RMS for astigmatism, SA, coma, and positive horizontal coma during the study period. After OK, there were significant positive correlations between the midperipheral-central thickness change difference and the changes in corneal and ocular RMS of total HOAs and SA (r range: 0.281 to 0.492, P<0.05). Only the change of corneal coma RMS was correlated with midperipheral-central thickness change difference (r=0.270, P<0.05). The change in corneal horizontal coma was correlated with the temporal-nasal thickness change difference (r=-0.289, P<0.05). CONCLUSIONS: Overnight OK caused unique changes in corneal thickness profiles at the vertical and horizontal meridians and increased corneal and ocular HOAs related to corneal reshaping.

Slit2 regulates the dispersal of oligodendrocyte precursor cells via Fyn/RhoA signaling.

Oligodendrocyte precursor cells (OPCs) are a unique type of glia that are responsible for the myelination of the central nervous system. OPC migration is important for myelin formation during central nervous system development and repair. However, the precise extracellular and intracellular mechanisms that regulate OPC migration remain elusive. Slits were reported to regulate neurodevelopmental processes such as migration, adhesion, axon guidance, and elongation through binding to roundabout receptors (Robos). However, the potential roles of Slits/Robos in oligodendrocytes remain unknown. In this study, Slit2 was found to be involved in regulating the dispersal of OPCs through the association between Robo1 and Fyn. Initially, we examined the expression of Robos in OPCs both in vitro and in vivo. Subsequently, the Boyden chamber assay showed that Slit2 could inhibit OPC migration. RoboN, a specific inhibitor of Robos, could significantly attenuate this effect. The effects were confirmed through the explant migration assay. Furthermore, treating OPCs with Slit2 protein deactivated Fyn and increased the level of activated RhoA-GTP. Finally, Fyn was found to form complexes with Robo1, but this association was decreased after Slit2 stimulation. Thus, we demonstrate for the first time that Slit2 regulates the dispersal of oligodendrocyte precursor cells through Fyn and RhoA signaling.

Olfactory ensheathing cells: the primary innate immunocytes in the olfactory pathway to engulf apoptotic olfactory nerve debris.

The olfactory system is an unusual tissue in which olfactory receptor neurons (ORNs) are continuously replaced throughout the life of mammals. Clearance of the apoptotic ORNs corpses is a fundamental process serving important functions in the regulation of olfactory nerve turnover and regeneration. However, little is known about the underlying mechanisms. Olfactory ensheathing cells (OECs) are a unique type of glial cells that wrap olfactory axons and support their continual regeneration from the olfactory epithelium to the bulb. In the present study, OECs were identified to exist in two different states, resting and reactive, in which resting OECs could be activated by LPS stimulation and functioned as phagocytes for cleaning apoptotic ORNs corpses. Confocal analysis revealed that dead ORNs debris were engulfed by OECs and co-localized with lysosome associated membrane protein 1. Moreover, phosphatidylserine (PS) receptor was identified to express on OECs, which allowed OECs to recognize apoptotic ORNs by binding to PS. Importantly, engulfment of olfactory nerve debris by OECs was found in olfactory mucosa under normal turnover and was significantly increased in the animal model of olfactory bulbectomy, while little phagocytosis by Iba-1-positive microglia/macrophages was observed. Together, these results implicate OEC as a primary innate immunocyte in the olfactory pathway, and suggest a cellular and molecular mechanism by which ORNs corpses are removed during olfactory nerve turnover and regeneration.

Bioinformatics identification of prognostic genes and potential interaction analysis in renal cell carcinoma.

Background: Renal cell carcinoma (RCC) is one of the ten most prevalent cancers in the world and its incidence has been rising over the past decade. However, effective biomarkers to predict the prognosis of patients remains absent, and the exact molecular mechanism of the disease remains unclear. Therefore, the identification of key genes and their biological pathways are of great significance to identify the differential expressed genes associated with the prognosis for patients with RCC, and to further explore their potential protein-protein interactions (PPIs) in tumorigenesis. Methods: The gene expression microarray data for GSE15641 and GSE40435 were extracted from the Gene Expression Omnibus (GEO) database, including 150 primary tumors and their matched adjacent non-tumor tissues. Afterwards, gene expression for fold changes (FCs) and P value for tumor and non-tumor tissues were analyzed using online tool GEO2R. Gene expression with logFCs of greater than two combined with P value of lower than 0.01 were considered as candidate targets for treatment of RCC. The survival analysis of candidate genes was performed by online software OncoLnc. The PPI network was implemented with Search Tool for the Retrieval of Interacting Genes (STRING). Results: In total, there were 625 differentially expressed genes (DEGs) in GSE15641, including 415 increased and 210 decreased genes. A total of 343 DEGs were identified in the GSE40435 with 101 upregulated and 242 downregulated genes, the 20 genes with highest FC in high or low expression in each database were summarized. Five candidate genes were overlapped genes in the two GEO datasets. However, aldolase, fructose-bisphosphate B (ALDOB) was found to be the only gene affecting the prognosis. A number of critical genes were identified behind the mechanism, of which they interacted with ALDOB. Among them, phosphofructokinase, platelet (PFKP), phosphofructokinase, muscle (PFKM), pyruvate kinase L/R (PKLR), and fructose-bisphosphatase 1 (FBP1) showed a better prognosis, whereas only glyceraldehyde-3-phosphate dehydrogenase (GAPDH) rendered a bleak outcome. Conclusions: Five genes were found to be overlappingly expressed in the top 20 greatest FC in two human GEO datasets. This is of great value in the treatment and prognosis of RCC.

Small molecules reprogram reactive astrocytes into neuronal cells in the injured adult spinal cord.

INTRODUCTION: Ectopic expression of transcription factor-mediated in vivo neuronal reprogramming provides promising strategy to compensate for neuronal loss, while its further clinical application may be hindered by delivery and safety concerns. As a novel and attractive alternative, small molecules may offer a non-viral and non-integrative chemical approach for reprogramming cell fates. Recent definitive evidences have shown that small molecules can convert non-neuronal cells into neurons in vitro. However, whether small molecules alone can induce neuronal reprogramming in vivo remains largely unknown. OBJECTIVES: To identify chemical compounds that can induce in vivo neuronal reprogramming in the adult spinal cord. METHODS: Immunocytochemistry, immunohistochemistry, qRT-PCR and fate-mapping are performed to analyze the role of small molecules in reprogramming astrocytes into neuronal cells in vitro and in vivo. RESULTS: By screening, we identify a chemical cocktail with only two chemical compounds that can directly and rapidly reprogram cultured astrocytes into neuronal cells. Importantly, this chemical cocktail can also successfully trigger neuronal reprogramming in the injured adult spinal cord without introducing exogenous genetic factors. These chemically induced cells showed typical neuronal morphologies and neuron-specific marker expression and could become mature and survive for more than 12 months. Lineage tracing indicated that the chemical compound-converted neuronal cells mainly originated from post-injury spinal reactive astrocytes. CONCLUSION: Our proof-of-principle study demonstrates that in vivo glia-to-neuron conversion can be manipulated in a chemical compound-based manner. Albeit our current chemical cocktail has a lowreprogramming efficiency, it will bring in vivo cell fate reprogramming closer to clinical application in brain and spinal cord repair. Future studies should focus on further refining our chemical cocktail and reprogramming approach to boost the reprogramming efficiency.

A novel OPA1 mutation in a Chinese family with autosomal dominant optic atrophy.

A large four-generation Chinese family with autosomal dominant optic atrophy (ADOA) was investigated in the present study. Eight of the family members were affected in this pedigree. The affected family members exhibited early-onset and progressive visual impairment, resulting in mild to profound loss of visual acuity. The average age-at-onset was 15.9years. A new heterozygous mutation c.C1198G was identified by sequence analysis of the 12th exon of the OPA1 gene. This mutation resulted in a proline to alanine substitution at codon 400, which was located in an evolutionarily conserved region. This missense mutation in the GTPase domain was supposed to result in a loss of function for the encoded protein and act through a dominant negative effect. No other mutations associated with optic atrophy were found in our present study. The c.C1198G heterozygous mutation in the OPA1 gene may be a novel key pathogenic mutation in this pedigree with ADOA. Furthermore, additional nuclear modifier genes, environmental factors, and psychological factors may also contribute to the phenotypic variability of ADOA in this pedigree.

Repeated measurements of the anterior segment during accommodation using long scan depth optical coherence tomography.

OBJECTIVES: The aim was to determine the repeatability of ultralong scan depth spectral-domain optical coherence tomography (SD-OCT) measurements of the ocular anterior segment during accommodation. METHODS: The center wavelength of the SD-OCT light source was 840 nm with a bandwidth of 50 nm. The ocular axial resolution of the system was approximately 6.0 µm, and the scan depth was 7.2 mm in air. Twenty eyes of 20 healthy subjects were imaged with a custom-built, ultralong scan depth SD-OCT during 2 visits. The anterior segment images were acquired during nonaccommodative and maximal accommodative states. After image processing and correction, the true values of the morphometric dimensions of the anterior eye were obtained. The variables of the two states from two visits were compared. RESULTS: For the corrected anterior segment images, the variables did not significantly differ from one visit to the next. The values of anterior chamber depth, pupil diameter, and the radius of the lens anterior surface curvature during accommodation were significantly smaller than those during the nonaccommodative state. The lens thickness significantly increased with accommodation. There was no significant difference in the posterior surface curvature of the lens between the two states. CONCLUSIONS: Ultralong scan depth SD-OCT holds promise for quantifying dimensional changes in the eye during accommodation. The instrument demonstrated good repeatability of ocular anterior segment dimensional measurements during accommodation.

Visualization of the precorneal tear film using ultrahigh resolution optical coherence tomography in dry eye.

PURPOSE: To visualize the precorneal tear film (PCTF) in dry eye patients using ultrahigh resolution optical coherence tomography (UHR-OCT). METHODS: A custom-built UHR-OCT with ultrahigh resolution (~3 µm) was used to image the PCTF at the vertical meridian. Eighteen right eyes of 18 previously diagnosed dry eye patients (9 men and 9 women, age, 47.8±20.7 years) with aqueous tear deficiency were studied. Images were taken during normal and delayed blinking. The visualized PCTF was measured directly. An indirect calculation was used to obtain the thickness in cases where the PCTF could not be visualized. RESULTS: During normal blinking, the PCTF was visualized in 5 of 18 eyes (27.8%) with an average PCTF thickness of 5.8 µm (SD, 1.3 µm). During delayed blinking, the PCTF was visualized in 11 eyes (61.1%) with a significantly increased average thickness of 7.3 µm (SD, 0.9 µm; P<0.05). The percent increase of the visualized PCTF thickness was higher during delayed blinking compared with normal blinking (χ test, P<0.05). The averaged PCTF was 4.4 µm during normal blinking, and the PCTF thickness was significantly increased to 6.6 µm (SD, 2.9 µm; P<0.05) during delayed blinking. CONCLUSIONS: We report the first visualization of PCTF in vivo in dry eye patients with UHR-OCT. Precorneal tear film can be directly visualized in some eyes during both normal and delayed blinking, and it seemed thicker during delayed blinking compared with normal blinking.

Early embryonic transcriptomes of Zeugodacus tau provide insight into sex determination and differentiation genes.

Zeugodacus tau (Walker) is an invasive pest. The sterile insect technique is an environment-friendly method for pest control. Understanding the mechanism of sex determination will contribute to improving efficiency of this technique. In this study, we identified the transformer (tra) gene in Z. tau. One female-specific and two male-specific isoforms of tra were found in Z. tau, and the male-specific splicing pattern of tra was found to occur 5 h after egg laying. We performed transcriptome sequencing at 1 h (E1), 5 h (E5), and 9 h (E9) after egg laying and obtained high-quality transcriptome libraries of early embryo development. We identified 13 297 and 11 713 differentially expressed genes (DEGs) from E5 versus E1 and E9 versus E1 comparisons, respectively. To explore the potential functions of the DEGs during embryonic development, Gene Ontology, Clusters of Orthologous Groups of proteins, and Kyoto Encyclopedia of Genes and Genomes analyses were performed. Twenty-six genes potentially involved in sex determination or differentiation, including Maleness-on-the-Y (MoY), were identified in Z. tau. To verify the transcriptome results, 15 genes were selected for quantitative real-time PCR validation. The results were consistent with the transcriptome sequencing results. Moreover, U2 small nuclear riboprotein auxiliary factor (U2AF-50), female lethal d (fl(2)d), and virilizer (vir) were highly expressed at E5, indicating that they may be related to the sex-specific splicing of tra. Further functional analysis is needed to confirm this speculation. Our data provide an insight into the mechanism underlying sex determination and differentiation in tephritid species.