Impaired Reorganization of Centrosome Structure Underlies Human Infantile Dilated Cardiomyopathy.

BACKGROUND: During cardiomyocyte maturation, the centrosome, which functions as a microtubule organizing center in cardiomyocytes, undergoes dramatic structural reorganization where its components reorganize from being localized at the centriole to the nuclear envelope. This developmentally programmed process, referred to as centrosome reduction, has been previously associated with cell cycle exit. However, understanding of how this process influences cardiomyocyte cell biology, and whether its disruption results in human cardiac disease, remains unknown. We studied this phenomenon in an infant with a rare case of infantile dilated cardiomyopathy (iDCM) who presented with left ventricular ejection fraction of 18% and disrupted sarcomere and mitochondria structure. METHODS: We performed an analysis beginning with an infant who presented with a rare case of iDCM. We derived induced pluripotent stem cells from the patient to model iDCM in vitro. We performed whole exome sequencing on the patient and his parents for causal gene analysis. CRISPR/Cas9-mediated gene knockout and correction in vitro were used to confirm whole exome sequencing results. Zebrafish and Drosophila models were used for in vivo validation of the causal gene. Matrigel mattress technology and single-cell RNA sequencing were used to characterize iDCM cardiomyocytes further. RESULTS: Whole exome sequencing and CRISPR/Cas9 gene knockout/correction identified RTTN, the gene encoding the centrosomal protein RTTN (rotatin), as the causal gene underlying the patient's condition, representing the first time a centrosome defect has been implicated in a nonsyndromic dilated cardiomyopathy. Genetic knockdowns in zebrafish and Drosophila confirmed an evolutionarily conserved requirement of RTTN for cardiac structure and function. Single-cell RNA sequencing of iDCM cardiomyocytes showed impaired maturation of iDCM cardiomyocytes, which underlie the observed cardiomyocyte structural and functional deficits. We also observed persistent localization of the centrosome at the centriole, contrasting with expected programmed perinuclear reorganization, which led to subsequent global microtubule network defects. In addition, we identified a small molecule that restored centrosome reorganization and improved the structure and contractility of iDCM cardiomyocytes. CONCLUSIONS: This study is the first to demonstrate a case of human disease caused by a defect in centrosome reduction. We also uncovered a novel role for RTTN in perinatal cardiac development and identified a potential therapeutic strategy for centrosome-related iDCM. Future study aimed at identifying variants in centrosome components may uncover additional contributors to human cardiac disease.

Pathological high intraocular pressure induces glial cell reactive proliferation contributing to neuroinflammation of the blood-retinal barrier via the NOX2/ET-1 axis-controlled ERK1/2 pathway.

BACKGROUND: NADPH oxidase (NOX), a primary source of endothelial reactive oxygen species (ROS), is considered a key event in disrupting the integrity of the blood-retinal barrier. Abnormalities in neurovascular-coupled immune signaling herald the loss of ganglion cells in glaucoma. Persistent microglia-driven inflammation and cellular innate immune system dysregulation often lead to deteriorating retinal degeneration. However, the crosstalk between NOX and the retinal immune environment remains unresolved. Here, we investigate the interaction between oxidative stress and neuroinflammation in glaucoma by genetic defects of NOX2 or its regulation via gp91ds-tat. METHODS: Ex vivo cultures of retinal explants from wildtype C57BL/6J and Nox2 -/- mice were subjected to normal and high hydrostatic pressure (Pressure 60 mmHg) for 24 h. In vivo, high intraocular pressure (H-IOP) was induced in C57BL/6J mice for two weeks. Both Pressure 60 mmHg retinas and H-IOP mice were treated with either gp91ds-tat (a NOX2-specific inhibitor). Proteomic analysis was performed on control, H-IOP, and treatment with gp91ds-tat retinas to identify differentially expressed proteins (DEPs). The study also evaluated various glaucoma phenotypes, including IOP, retinal ganglion cell (RGC) functionality, and optic nerve (ON) degeneration. The superoxide (O2-) levels assay, blood-retinal barrier degradation, gliosis, neuroinflammation, enzyme-linked immunosorbent assay (ELISA), western blotting, and quantitative PCR were performed in this study. RESULTS: We found that NOX2-specific deletion or activity inhibition effectively attenuated retinal oxidative stress, immune dysregulation, the internal blood-retinal barrier (iBRB) injury, neurovascular unit (NVU) dysfunction, RGC loss, and ON axonal degeneration following H-IOP. Mechanistically, we unveiled for the first time that NOX2-dependent ROS-driven pro-inflammatory signaling, where NOX2/ROS induces endothelium-derived endothelin-1 (ET-1) overexpression, which activates the ERK1/2 signaling pathway and mediates the shift of microglia activation to a pro-inflammatory M1 phenotype, thereby triggering a neuroinflammatory outburst. CONCLUSIONS: Collectively, we demonstrate for the first time that NOX2 deletion or gp91ds-tat inhibition attenuates iBRB injury and NVU dysfunction to rescue glaucomatous RGC loss and ON axon degeneration, which is associated with inhibition of the ET-1/ERK1/2-transduced shift of microglial cell activation toward a pro-inflammatory M1 phenotype, highlighting NOX2 as a potential target for novel neuroprotective therapies in glaucoma management.

The Impact of Aging on the Function of Retinal Ganglion Cells.

Aging is a major risk factor for retinal neurodegenerative diseases. Aged mammalian retinal ganglion cells (RGCs) lack the ability to regenerate axons after injury. Rodent models suggest that older age increases the vulnerability of RGCs to injury and impairs RGC function as well as their functional recovery. Molecular changes - including decreased circulating levels of brain-derived neurotrophic factor (BDNF) - might contribute to impaired RGC dendritic extension during aging. Moreover, age-related mitochondrial dysfunction plays a major role in aging processes, as it leads to reduced adenosine triphosphate and increased generation of reactive oxygen species. Autophagy activity is necessary for the maintenance of cellular homeostasis and decreases with aging in the central nervous system. During aging, vascular insufficiency may lead to impaired oxygen and nutrient supply to RGCs. Microglial cells undergo morphological changes and functional impairment with aging, which might compromise retinal homeostasis and promote an inflammatory environment. Addressing these age-related changes by means of a low-energy diet, exercise, and neurotrophic factors might prevent age-related functional impairment of RGCs. This review focuses on the current understanding of aging RGCs and key players modulating those underlying mechanisms.

Insight into the lncRNA-mRNA Co-Expression Profile and ceRNA Network in Lipopolysaccharide-Induced Acute Lung Injury.

Long non-coding RNAs (lncRNAs) participate in acute lung injury (ALI). However, their latent biological function and molecular mechanism have not been fully understood. In the present study, the global expression profiles of lncRNAs and mRNAs between the control and lipopolysaccharide (LPS)-stimulated groups of human normal lung epithelial cells (BEAS-2B) were determined using high-throughput sequencing. Overall, a total of 433 lncRNAs and 183 mRNAs were differentially expressed. A lncRNA-mRNA co-expression network was established, and then the top 10 lncRNAs were screened using topological methods. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis results showed that the key lncRNAs targeting mRNAs were mostly enriched in the inflammatory-related biological processes. Gene set variation analysis and Pearson's correlation coefficients confirmed the close correlation for the top 10 lncRNAs with inflammatory responses. A protein-protein interaction network analysis was conducted based on the key lncRNAs targeting mRNAs, where IL-1ß, IL-6, and CXCL8 were regarded as the hub genes. A competing endogenous RNA (ceRNA) modulatory network was created with five lncRNAs, thirteen microRNAs, and twelve mRNAs. Finally, real-time quantitative reverse transcription-polymerase chain reaction was employed to verify the expression levels of several key lncRNAs in BEAS-2B cells and human serum samples.

SIRT6 ameliorates LPS-induced apoptosis and tight junction injury in ARDS through the ERK1/2 pathway and autophagy.

Sirtuin6 (SIRT6) has been demonstrated to be involved in a range of physiological processes and diseases, while its role in acute respiratory distress syndrome (ARDS) remains unclear. Therefore, this study focused on the role and underlying mechanism of SIRT6 in ARDS with the aim of identifying potential therapeutic targets. In this study, we found that SIRT6 was significantly decreased in lipopolysaccharide (LPS)-induced A549 cells and a murine model. In vitro overexpression of SIRT6 restored the expression of tight junction proteins (ZO-1 and occludin) and alleviated cell apoptosis and inflammation, while knockdown of SIRT6 aggravated the loss of tight junction proteins (ZO-1 and occludin) and promoted cell apoptosis and inflammation in LPS-induced A549 cells. Furthermore, the overexpression of SIRT6 enhanced autophagy and inhibited the ERK1/2 pathway, while the knockdown of SIRT6 inhibited autophagy and activated the ERK1/2 pathway. The autophagy activator rapamycin and the ERK1/2 inhibitor PD98059 rescued the effects of SIRT6 knockdown on tight junction proteins, apoptosis, and inflammation. Mechanistically, SIRT6 deacetylated histone 3 at Lys9 to negatively regulate the ERK1/2 pathway. In vivo, the SIRT6-specific inhibitor OSS_128167 also significantly accelerated LPS-induced loss of tight junction proteins, lung inflammation, and apoptosis. Meanwhile, the SIRT6-specific inhibitor OSS_128167 also activated the ERK1/2 pathway and inhibited lung autophagy. These results suggested that SIRT6 could ameliorate the loss of tight junction proteins, inflammation, and apoptosis in LPS-induced ARDS by inhibiting the ERK1/ 2 pathway and enhancing autophagy, indicating that SIRT6 plays a beneficial role in ARDS and might be a potential therapeutic target for ARDS.

The AMPK-PP2A axis in insect fat body is activated by 20-hydroxyecdysone to antagonize insulin/IGF signaling and restrict growth rate.

In insects, 20-hydroxyecdysone (20E) limits the growth period by triggering developmental transitions; 20E also modulates the growth rate by antagonizing insulin/insulin-like growth factor signaling (IIS). Previous work has shown that 20E cross-talks with IIS, but the underlying molecular mechanisms are not fully understood. Here we found that, in both the silkworm Bombyx mori and the fruit fly Drosophila melanogaster, 20E antagonized IIS through the AMP-activated protein kinase (AMPK)-protein phosphatase 2A (PP2A) axis in the fat body and suppressed the growth rate. During Bombyx larval molt or Drosophila pupariation, high levels of 20E activate AMPK, a molecular sensor that maintains energy homeostasis in the insect fat body. In turn, AMPK activates PP2A, which further dephosphorylates insulin receptor and protein kinase B (AKT), thus inhibiting IIS. Activation of the AMPK-PP2A axis and inhibition of IIS in the Drosophila fat body reduced food consumption, resulting in the restriction of growth rate and body weight. Overall, our study revealed an important mechanism by which 20E antagonizes IIS in the insect fat body to restrict the larval growth rate, thereby expanding our understanding of the comprehensive regulatory mechanisms of final body size in animals.

The Association between Vascular Abnormalities and Glaucoma-What Comes First?

Glaucoma is a leading cause of irreversible blindness worldwide. While intraocular pressure (IOP) presents a major risk factor, the underlying pathophysiology still remains largely unclear. The correlation between vascular abnormalities and glaucoma has been deliberated for decades. Evidence for a role played by vascular factors in the pathogenesis of glaucomatous neurodegeneration has already been postulated. In addition, the fact that glaucoma causes both structural and functional changes to retinal blood vessels has been described. This review aims to investigate the published evidence concerning the relationship between vascular abnormalities and glaucoma, and to provide an overview of the "chicken or egg" dilemma in glaucoma. In this study, several biomarkers of glaucoma progression from a vascular perspective, including endothelin-1 (ET-1), nitric oxide, vascular endothelial growth factor (VEGF), and matrix metalloproteinases (MMPs), were identified and subsequently assessed for their potential as pharmacological intervention targets.

Preparation of multifunctional mesoporous SiO2nanoparticles and anti-tumor action.

A targeted drug delivery system was developed to accumulate specific drugs around tumor cells based on the redox, temperature, and enzyme synergistic responses of mesoporous silica nanoparticles. Mesoporous silica nanoparticles (MSN-NH2) and Doxorubicin (DOX) for tumor therapy were prepared and loaded into the pores of MSN- NH2 to obtain DOX@MSN(DM NPs). Hyaluronic acid (HA) was used as the backbone and disulfide bond was used as the linker arm to graft carboxylated poly (N-isopropylacrylamide)(PNIPAAm-COOH) to synthesize the macromolecular copolymer (HA-SS-PNIPAAm), which was modified to DM NPs with capped ends to obtain the nano-delivery system DOX@MSN@HA-SS-PNIPAAm(DMHSP NPs), and a control formulation was prepared in a similar way. DMHSP NPs specifically entered tumor cells via CD44 receptor-mediated endocytosis; the high GSH concentration (10 mM) of cells severed the disulfide bonds, the hyaluronidase sheared the capped HA to open the pores, and increased tumor microenvironment temperature due to immune response can trigger the release of encapsulated drugs in thermosensitive materials.In vitroandin vivoantitumor and hemolysis assays showed that DMHSP NPs can accurately target hepatocellular carcinoma cells with a good safety profile and have synergistic effects, which meant DMHSP NPs had great potential for tumor therapy.

The lipolysis pathway sustains normal and transformed stem cells in adult Drosophila.

Cancer stem cells (CSCs) may be responsible for tumour dormancy, relapse and the eventual death of most cancer patients. In addition, these cells are usually resistant to cytotoxic conditions. However, very little is known about the biology behind this resistance to therapeutics. Here we investigated stem-cell death in the digestive system of adult Drosophila melanogaster. We found that knockdown of the coat protein complex I (COPI)-Arf79F (also known as Arf1) complex selectively killed normal and transformed stem cells through necrosis, by attenuating the lipolysis pathway, but spared differentiated cells. The dying stem cells were engulfed by neighbouring differentiated cells through a draper-myoblast city-Rac1-basket (also known as JNK)-dependent autophagy pathway. Furthermore, Arf1 inhibitors reduced CSCs in human cancer cell lines. Thus, normal or cancer stem cells may rely primarily on lipid reserves for energy, in such a way that blocking lipolysis starves them to death. This finding may lead to new therapies that could help to eliminate CSCs in human cancers.

Scavenging Free Iron Reduces Arteriolar Microvasospasms After Experimental Subarachnoid Hemorrhage.

BACKGROUND AND PURPOSE: Subarachnoid hemorrhage (SAH) is associated with acute and delayed cerebral ischemia resulting in high acute mortality and severe chronic neurological deficits. Spasms of the pial and intraparenchymal microcirculation (microvasospasms) contribute to acute cerebral ischemia after SAH; however, the underlying mechanisms remain unknown. We hypothesize that free iron (Fe3+) released from hemolytic red blood cells into the subarachnoid space may be involved in microvasospasms formation. METHODS: Male C57BL/6 mice (n=8/group) received 200 mg/kg of the iron scavenger deferoxamine or vehicle intravenously and were then subjected to SAH by filament perforation. Microvasospasms of pial and intraparenchymal vessels were imaged three hours after SAH by in vivo 2-photon microscopy. RESULTS: Microvasospasms occurred in all investigated vessel categories down to the capillary level. Deferoxamine significantly reduced the number of microvasospasms after experimental SAH. The effect was almost exclusively observed in larger pial arterioles (>30 µm) covered with blood. CONCLUSIONS: These results provide proof-of-principle evidence that Fe3+ is involved in the formation of arteriolar microvasospasms after SAH and that arteriolar and capillary microvasospasms are triggered by different mechanisms. Deciphering the mechanisms of Fe3+-induced microvasospasms may result in novel therapeutic strategies for SAH patients.

Chronic social defeat stress causes retinal vascular dysfunction.

PURPOSE: The roles of vascular dysfunction and chronic stress have been extensively discussed in the pathophysiology of glaucoma. Our aim was to test whether chronic stress causes retinal vascular dysfunction and therewith induces retinal ganglion cells (RGCs) loss. METHODS: Twelve mice underwent chronic social defeat (CSD) stress, while 12 mice received control treatment only. Intraocular pressure (IOP) was measured with a rebound tonometer. Blood plasma corticosterone concentration and adrenal gland weight were used to assess stress levels. Brn-3a staining in retinas and PPD staining in optic nerve cross sections were conducted to assess the survival of RGCs and axons respectively. The ET-1 and α-SMA levels were determined in retina. Retinal vascular autoregulation, functional response to various vasoactive agents and vascular mechanics were measured using video microscopy. RESULTS: No significant difference in IOP levels was observed during and after CSD between CSD mice and controls. CSD stress caused hypercortisolemia 2 days post-CSD. However, increased corticosterone levels went back to normal 8 months after CSD. CSD-exposed mice developed adrenal hyperplasia 3 days post-CSD, which was normalized by 8 months. RGC and axon survival were similar between CSD mice and controls. However, CSD stress caused irreversible, impaired autoregulation and vascular dysfunction of retinal arterioles in CSD mice. In addition, impaired maximal dilator capacity of retinal arterioles was observed 8 months post-CSD rather than 3 days post-CSD. Remarkably, ET-1 levels were increased 3 days post-CSD while α-SMA levels were decreased 8 months post-CSD. CONCLUSIONS: We found that CSD stress does not cause IOP elevation, nor loss of RGCs and their axons. However, it strikingly causes irreversible impaired autoregulation and endothelial function in murine retinal arterioles. In addition, CSD changed vascular mechanics on a long-term basis. Increased ET-1 levels and loss of pericytes in retina vessels may involve in this process.

Keratomycosis Caused by a Rare Pathogen, Myrothecium verrucaria.

PURPOSE: To report a case of keratomycosis caused by a very rare pathogen, Myrothecium verrucaria. METHODS: This is a case report. A 53-year-old man complaint of left eye redness, irritation, intermittent pain after ashes entered his left eye. The patient was examined by slit lamp, anterior segment OCT and in vivo confocal microscopy. The HRT III-RCM image showed massive interlocking white thin lines in the cornea stroma. Corneal scrapings were collected for pathogen culture and PCR test. M. verrucaria was isolated and identified. RESULTS: Hourly topical natamycin (5%) and voriconazole (10 mg/ml) was given as well as intravenous fluconazole (200 mg per day). Treatment was continued with oral itraconazole, 200 mg/day, topical natamycin (5%), 4 times/day, and pranoprofen, 4 times/day. The therapy was tapered off over one and half a month. The cornea lesion healed with scar formation two months later. CONCLUSIONS: This is the first case report of M. verrucaria keratomycosis in China. We are the first to show the characteristic of M. verrucaria on cornea with In vivo confocal microscopy. A combination treatment of tropical natamycin, voriconazole and systemic fluconazole was effective in the treatment of M. verrucaria.

Energy Metabolism in the Inner Retina in Health and Glaucoma.

Glaucoma, the leading cause of irreversible blindness, is a heterogeneous group of diseases characterized by progressive loss of retinal ganglion cells (RGCs) and their axons and leads to visual loss and blindness. Risk factors for the onset and progression of glaucoma include systemic and ocular factors such as older age, lower ocular perfusion pressure, and intraocular pressure (IOP). Early signs of RGC damage comprise impairment of axonal transport, downregulation of specific genes and metabolic changes. The brain is often cited to be the highest energy-demanding tissue of the human body. The retina is estimated to have equally high demands. RGCs are particularly active in metabolism and vulnerable to energy insufficiency. Understanding the energy metabolism of the inner retina, especially of the RGCs, is pivotal for understanding glaucoma's pathophysiology. Here we review the key contributors to the high energy demands in the retina and the distinguishing features of energy metabolism of the inner retina. The major features of glaucoma include progressive cell death of retinal ganglions and optic nerve damage. Therefore, this review focuses on the energetic budget of the retinal ganglion cells, optic nerve and the relevant cells that surround them.

Role of Pial Microvasospasms and Leukocyte Plugging for Parenchymal Perfusion after Subarachnoid Hemorrhage Assessed by In Vivo Multi-Photon Microscopy.

Subarachnoid hemorrhage (SAH) is associated with acute and delayed cerebral ischemia. We suggested spasms of pial arterioles as a possible mechanism; however, it remained unclear whether and how pial microvasospasms (MVSs) induce cerebral ischemia. Therefore, we used in vivo deep tissue imaging by two-photon microscopy to investigate MVSs together with the intraparenchymal microcirculation in a clinically relevant murine SAH model. Male C57BL/6 mice received a cranial window. Cerebral vessels and leukocytes were labelled with fluorescent dyes and imaged by in vivo two-photon microscopy before and three hours after SAH induced by filament perforation. After SAH, a large clot formed around the perforation site at the skull base, and blood distributed along the perivascular space of the middle cerebral artery up to the cerebral cortex. Comparing the cerebral microvasculature before and after SAH, we identified three different patterns of constrictions: pearl string, global, and bottleneck. At the same time, the volume of perfused intraparenchymal vessels and blood flow velocity in individual arterioles were significantly reduced by more than 60%. Plugging of capillaries by leukocytes was observed but infrequent. The current study demonstrates that perivascular blood is associated with spasms of pial arterioles and that these spasms result in a significant reduction in cortical perfusion after SAH. Thus, the pial microvasospasm seems to be an important mechanism by which blood in the subarachnoid space triggers cerebral ischemia after SAH. Identifying the mechanisms of pial vasospasm may therefore result in novel therapeutic options for SAH patients.

Hydrogen Sulfide: Novel Endogenous and Exogenous Modulator of Oxidative Stress in Retinal Degeneration Diseases.

Oxidative stress (OS) damage can cause significant injury to cells, which is related to the occurrence and development of many diseases. This pathological process is considered to be the first step to trigger the death of outer retinal neurons, which is related to the pathology of retinal degenerative diseases. Hydrogen sulfide (H2S) has recently received widespread attention as a physiological signal molecule and gas neuromodulator and plays an important role in regulating OS in eyes. In this article, we reviewed the OS responses and regulatory mechanisms of H2S and its donors as endogenous and exogenous regulators in retinal degenerative diseases. Understanding the relevant mechanisms will help to identify the therapeutic potential of H2S in retinal degenerative diseases.

The effect of Wnt/ß-catenin pathway on the scleral remolding in the mouse during form deprivation.

BACKGROUND: Many reports have shown that Wnt/ß-Catenin pathway is associated with a variety of diseases, but its role in the pathogenesis of myopia is still unknown. In order to clarify the role of Wnt/ß-catenin pathway in the development of form deprivation myopia (FDM), this study investigated the expression of scleral Wls, ß-catenin and TCF4 in mice model of form deprivation (FD) myopia. METHODS: Three parallel experimental groups, including FD, monocular exposure (SC) and binocular exposure (NC) group, were designed to investigate the effects of Wnt/ß-Catenin pathway on scleral remodeling mouse during form deprivation in three-week-old C57BL/6 mice. Diopters and axial lengths (AL) in each sample were measured with an infrared eccentric refractometer or spectral-domain optical coherence tomography. The expression of scleral Wls, ß-catenin and TCF4 were detected with Western blot. Morphological changes of posterior sclera were observed with a transmission electron microscope (TEM). The above characterization and analysis were performed on the 0th, 7th, 14th, 21st and 28th days, respectively. RESULTS: The difference of diopter and AL between the three groups (SC, NC and FD group) gradually increased with the prolongation of FD time (except AL between SC and NC groups). The changes of diopter and AL gradually increased with the prolongation of FD time. Especially, the diopter and AL will increase sharply after FD lasts for a long time, such as the measurement on the 21st for diopter and 28th days for AL. Most notably, the AL of FD eyes significantly increased after 28 days of deprivation. Thinning and disordered arrangement of collagen fibers and a decrease of extracellular matrix were observed with TEM. The expression of scleral Wls, ß-catenin and TCF4 increased with age in the NC and SC group. In FD group, they increased significantly on the 7th, 14th and 21st days but decreased on the 28th day. CONCLUSIONS: The expression of Wls, ß-Catenin and TCF4 to FD were more sensitive indicators than that of diopter and AL. Within the first 7 days of FD, the expression of Wls, ß-Catenin and TCF4 in sclera increased sharply. With the extension of FD duration, it gradually decreased. It is suggested that the Wnt/ß-catenin pathway might be involved in the scleral remodeling induced in FDM mice.

A retrospective study comparing DALK and PKP in the treatment of necrotizing stromal keratitis.

PURPOSE: To compare the clinical outcomes of deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PKP) in the treatment of necrotizing stromal keratitis (NSK). METHODS: A retrospective study of NSK patients who underwent keratoplasty between January 2015 and December 2017 in the Third Xiangya Hospital was carried out. Data including preoperative and postoperative best corrected visual acuity (BCVA), intraocular pressure, graft survival rates, corneal endothelial cell density, corneal topography and thickness were reviewed and analyzed by SPSS 23.0 software. RESULTS: Fifty patients were involved. Twenty-five patients received DALK, and the other half received PKP. The average follow-up period was 10.28 ± 5.92 months. At the end of the follow-up period, there were no significant differences in postoperative BCVA, recurrence of virus, graft rejection or graft failure between the two groups. There were also no significant differences in average central corneal thickness postoperatively at 3 months. However, the average corneal endothelial cell density at 3 months was significantly higher in the DALK group (2121.12 ± 450.80 cell/mm2 in the DALK group versus 1812.16 ± 340.38 cell/mm2 in the PKP group, P = 0.009). CONCLUSION: Both DALK and PKP could increase visual acuity and prevent the progression of NSK. There were no significant differences between DALK and PKP in postoperative BCVA, rate of rejection, graft failure or recurrence rate. DALK significantly reduced the loss of corneal endothelial cells.

First case of acute respiratory distress syndrome and alimentary tract hemorrhage following mass ingestion of methylisothiazolinone.

The frequency of methylisothiazolinone (MIT)-related health concerns regarding allergic contact dermatitis with a spongiotic reaction pattern and restrictive lung function indicating peripheral airway dysfunction caused by the use of humidifier disinfectant is increasingly rising. There is a limited number of evidences supporting the environmentally acute and mass exposure to MIT resulting in acute respiratory distress syndrome (ARDS). Here, we report the first case of ARDS and alimentary tract hemorrhage following mass ingestion of methylisothiazolinone.

[Morphological and Quantitative Changes in Retinal and Optic Nerve Vessels in Experimental Glaucoma Model with Elevated IOP for 7 Weeks]. / Erhöhter Augeninnendruck für 7 Wochen induziert lokale Gefäßveränderungen im experimentellen Glaukommodell in vivo.

INTRODUCTION: Glaucoma is characterised by progressive loss of retinal ganglion cells and axons. Experimental research has concentrated on understanding the pathophysiological mechanisms involved in glaucomatous damage. It is still a matter of debate whether neurons or capillaries are primarily damaged by elevated intraocular pressure (IOP). The aim of this study was to detect IOP-induced vascular changes in the vessels of the optic nerve head and the main vessels of the retina in vivo. METHODS: Experimental glaucoma was induced in adult Sprague Dawley rats by cauterisation of three episcleral veins of the left eye (n = 3). In vivo, retinal vessel calibre was measured manually using a peripapillary scan with SD-OCT (Heidelberg Engineering) at baseline and after seven weeks of IOP elevation. The animals were then sacrificed and the optic nerve was fixed with 30% glutaraldehyde and cross-sections stained with paraphenylene diamine to mark the vessels. Contralateral eyes served as controls. Pictures were taken and number of vessels, vessel calibre and area were calculated and compared. RESULTS: IOP was significantly elevated (p < 0.001). In optic nerve cross sections, the number of capillaries did not differ significantly between animals with elevated IOP and controls. However, vessel calibre and area were significantly reduced (p < 0.001) in glaucomatous optic nerves. The calibre of the retinal vessels was significantly lowered - by 9.22% (p = 0.021). CONCLUSION: Retinal arterioles and optic nerve capillaries respond sensitively to abnormal pressure elevation in vivo, showing high and early vulnerability. The vascular responses may influence secondary neuronal responses, which culminate in the death of ganglion cells and blindness, as occurs in clinical glaucoma.

Relaxin 2 fails to lower intraocular pressure and to dilate retinal vessels in rats.

PURPOSE: Recently, the vasodilator relaxin 2 has been introduced as a treatment for acute heart failure. However, its role on vessels of the eye and intraocular pressure (IOP) remains unclear though it has been hypothesized to induce a decrease IOP after intramuscular injection in humans. We aimed to test whether the hormone relaxin 2 lowers IOP and dilates retinal vessels in animals. METHODS: The IOP of female Sprague-Dawley rats before and after application of relaxin 2 was measured using an Icare Tonolab device calibrated for rats. Recombinant human relaxin 2 in phosphate-buffered saline with 0.1% bovine serum albumin was either applied as eye drops (1000, 2000 or 3000 ng/ml), injected intravitreally (500 ng/ml) or intravenously (13.3 µg/kg body weight). Retinal vessel thickness was monitored using infrared fundus images compiled with optical coherence tomography (Heidelberg Engineering) before and several time points after application of relaxin 2. RESULTS: Neither topical nor intravitreous or intravenous application of relaxin 2 lowered the IOP or changed the arterial or venous vessel diameter after 1 or 3 h after application. DISCUSSION: Now that relaxin 2 is more easily available, the hormone came again into focus as a potential glaucoma therapeutic. However, our study in rats could not support the hypothesis that relaxin 2 lowers IOP or dilates retinal vessels.