Using Electronic Health Record Data to Determine the Safety of Aqueous Humor Liquid Biopsies for Molecular Analyses.

Purpose: Knowing the surgical safety of anterior chamber liquid biopsies will support the increased use of proteomics and other molecular analyses to better understand disease mechanisms and therapeutic responses in patients and clinical trials. Manual review of operative notes from different surgeons and procedures in electronic health records (EHRs) is cumbersome, but free-text software tools could facilitate efficient searches. Design: Retrospective case series. Participants: A total of 1418 aqueous humor liquid biopsies from patients undergoing intraocular surgery. Methods: Free-text EHR searches were performed using the Stanford Research Repository cohort discovery tool to identify complications associated with anterior chamber paracentesis and subsequent endophthalmitis. Complications of the surgery unrelated to the biopsy were not reviewed. Main Outcome Measures: Biopsy-associated intraoperative complications and endophthalmitis. Results: A total of 1418 aqueous humor liquid biopsies were performed by 17 experienced surgeons. EHR free-text searches were 100% error-free for surgical complications, >99% for endophthalmitis (<1% false positive), and >93.6% for anesthesia type, requiring manual review for only a limited number of cases. More than 85% of cases were performed under local anesthesia without ocular muscle akinesia. Although the most common indication was cataract (50.1%), other diagnoses included glaucoma, diabetic retinopathy, uveitis, age-related macular degeneration, endophthalmitis, retinitis pigmentosa, and uveal melanoma. A 50- to 100-µL sample was collected in all cases using either a 30-gauge needle or a blunt cannula via a paracentesis. The median follow-up was >7 months. There was only one minor complication (0.07%) identified: a case of a small tear in Descemet membrane without long-term sequelae. No other complications occurred, including other corneal injuries, lens or iris trauma, hyphema, or suprachoroidal hemorrhage. There was no case of postoperative endophthalmitis. Conclusions: Anterior chamber liquid biopsy during intraocular surgery is a safe procedure and may be considered for large-scale collection of aqueous humor samples for molecular analyses. Free-text EHR searches are an efficient approach to reviewing intraoperative procedures. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Intraoperative optical coherence tomography-guided deep anterior lamellar keratoplasty.

Gauging stromal dissection depth is crucial to successfully perform deep anterior lamellar keratoplasty (DALK) surgery. Intraoperative optical coherence tomography (iOCT) offers a promising tool to aid DALK surgery but visualization of surgical maneuvers is impaired due to artifacts from metallic instruments. We describe a novel surgical technique utilizing suture-assisted iOCT guidance that facilitates clear visualization of corneal dissection planes during DALK. A stromal dissection tunnel is performed with a Fogla probe and its depth is subsequently identified by threading a 1 cm segment of 8-0 nylon into the tunnel. In contrast to the Fogla probe, the 8-0 nylon is conspicuously highlighted on iOCT. If the tunnel is too superficial, a separate, deeper stromal tunnel can be created and visualized again with the 8-0 nylon suture and iOCT. This iterative process facilitates a deep stromal dissection, increasing the probability of successful big-bubble formation and Descemet baring DALK surgery. This technique was utilized for a successful big-bubble DALK in a patient with severe keratoconus.

Preparing the Ocular Surface for a Boston Keratoprosthesis Type 1 Through En Bloc Minor Salivary Gland Transplantation and Mucous Membrane Grafting in End-Stage Stevens-Johnson Syndrome.

PURPOSE: This case describes the successful visual restoration of a patient with end-stage Stevens-Johnson syndrome (SJS) with a severely keratinized ocular surface. METHODS: This study is a case report. RESULTS: A 67-year-old man with SJS secondary to allopurinol sought visual rehabilitation options. His ocular surface was severely compromised from sequelae of chronic SJS, leaving him with light perception vision bilaterally. The left eye was completely keratinized with severe ankyloblepharon. The right eye had failed penetrating keratoplasty, limbal stem cell deficiency, and a keratinized ocular surface. The patient declined both a Boston type 2 keratoprosthesis and a modified osteo-odonto keratoprosthesis. Therefore, a staged approach was pursued with (1) systemic methotrexate to control ocular surface inflammation, (2) minor salivary gland transplant to increase ocular surface lubrication, (3) lid margin mucous membrane graft to reduce keratinization, and finally, (4) Boston type 1 keratoprosthesis for visual restoration. After minor salivary gland transplant and mucous membrane graft, the Schirmer score improved from 0 mm to 3 mm with improvement in ocular surface keratinization. This approach successfully restored the vision to 20/60, and the patient has retained the keratoprosthesis for over 2 years. CONCLUSIONS: Sight restoration options are limited in patients with end-stage SJS with a keratinized ocular surface, aqueous and mucin deficiency, corneal opacification, and limbal stem cell deficiency. This case demonstrates successful ocular surface rehabilitation and vision restoration in such a patient through a multifaceted approach that resulted in successful implantation and retention of a Boston type 1 keratoprosthesis.

Structural and Metabolic Imaging After Short-term Use of the Balance Goggles System in Glaucoma Patients: A Pilot Study.

PRCIS: Short-term use of the Balance Goggles System (BGS) in glaucoma patients was not associated with the observable changes in conventional ocular coherence tomography (OCT) imaging, but metabolic imaging using peripapillary flavoprotein fluorescence (FPF) may represent a useful adjuctive investigation. OBJECTIVE: To determine whether the intraocular pressure (IOP)-lowering effects of the BGS are accompanied by changes in retinal thickness measured by OCT, retinal vascular density measured by ocular coherence tomography-angiography (OCTA), or novel peripapillary metabolic profiling using FPF measured by a fundus camera. DESIGN: Prospective comparative case-series. SUBJECTS: Eight eyes from 8 patients with open angle glaucoma ranging from mild to severe. METHODS: In this prospective, single-center, open-label, nonrandomized, and single-arm study patients received a baseline evaluation including retinal imaging, then 1 hour of negative pressure application through the BGS, followed by repeat retinal imaging. Participants then used the BGS at home for 1 month and underwent a repeat evaluation at the conclusion of the trial. MAIN OUTCOME MEASURES: Changes in nerve fiber layer thickness, OCTA vascular parameters, and FPF scores. RESULTS: Mean baseline IOP was 18.0±3.1 mmHg and there was no significant change in IOP at follow-up. At 1 month compared with baseline, there was a statistically significant improvement in FPF optic nerve head rim scores (12.7±11.6 to 10.5±7.5; P =0.04). In addition, there was a trend toward an increase in retinal nerve fiber layer thickness after 1 month (69.5±14.2 to 72.0±13.7; P =0.1), but there were no statistically significant differences observable with any of the OCTA vascular parameters either at 1 hour or after 1 month. CONCLUSIONS: There were no significant changes observable using conventional OCT imaging after short-term use of the BGS, although metabolic imaging using FPF may be a useful potential biomarker to complement existing investigations. Additional studies are warranted to further investigate these changes.

Extraocular muscle contraction as a tool for benign paroxysmal positional vertigo diagnosis.

When diagnosing benign paroxysmal positional vertigo, extraocular muscle contraction and the nystagmus it causes, though recognized as an important indicator, is less commonly seen as a principal method of diagnosis. However, through determining the direction of resulting nystagmus during diagnostic tests such as the supine roll test and the Dix-Hallpike test, which semicircular canals are involved in individual cases of benign paroxysmal positional vertigo can be ascertained, in both cases involving only one semicircular canal or cases of multi-canal benign paroxysmal positional vertigo.

Effectiveness of Netarsudil as an Additional Therapy for Glaucoma in Patients Already on Maximally Tolerated Medical Therapy.

PURPOSE: This study seeks to evaluate the effectiveness of netarsudil (Rhopressa) in patients with inadequately controlled IOP on otherwise maximally tolerated medical therapy. METHODS: This is a retrospective study of patients started on netarsudil at Stanford University. Exclusion criteria included glaucoma surgery or laser within 6 months of starting netarsudil and other modifications to the baseline medication regimen within 4 weeks of starting netarsudil. The primary outcome was treatment success, defined as IOP reduction meeting a predetermined target, and no further medication, laser, or surgery recommended subsequent to starting netarsudil. RESULTS: Sixty-two eyes were included, and 36 (58%) achieved treatment success at first follow-up. Mean baseline IOP was 19.5 ± 5.6 mmHg on a mean of 3.5 ± 0.7 ocular hypotensive medications. The mean change in IOP from baseline to first follow-up was -3.53 mmHg (-17%). In patients who achieved treatment success, mean IOP change was -5.22 mmHg (-28.0%). Of the eyes with baseline IOP ≤ 20 mmHg, 69% achieved treatment success, compared to only 17% of eyes with baseline IOP ≥ 21 mmHg (P < 0.05). CONCLUSION: Netarsudil is effective in lowering IOP for patients on otherwise maximally tolerated medical therapy, for which glaucoma laser or surgery would have been the only remaining therapeutic options. Treatment success was more likely in eyes with baseline IOP under 20 mmHg.

Early clinical exposure improves medical students' recognition of the need for professionalism and interprofessional collaboration.

BACKGROUND: Medical students in Taiwan start their clerkship in their fifth year. A lack of early clinical exposure can mean they have a lack of medical professionalism and collaborative practice. This study investigates whether early engagement in hospital-based clinical practice could improve their understanding of these requirements. METHODS: From 2017 to 2019, a total of 59 medical students at the end of their third year joined a 2-week summer camp at the hospital. Every participant was assigned to work with one patient and they accompanied this patient throughout their hospital course. The students were also asked to interview other medical professionals within the hospital and to write up interview reports. In addition, they had to complete pre- and postcamp questionnaires which included 10 questions to evaluate their recognition of professionalism, doctor-patient relationships, and interprofessional collaboration. Answers to the questions were all rated using a 5-score Likert scale. RESULTS: The total postcamp Likert scores were significantly increased after the 2-week training camp compared with the precourse scores (pre- vs postcourse: 44.08 ± 0.45 vs 46.66 ± 0.33, p < 0.001). In addition, the students' recognition of medical professionalism, the importance of communication with patients, and their respect for other medical professionals were significantly improved after the 2-week training. CONCLUSION: Our data showed that early clinical exposure through a preclerkship summer camp can help medical students improve their recognition of medical professionalism and interprofessional collaboration.

Time-dependent deformation of artificial muscles based on Nylon 6.

Considering the potential applications of the Nylon 6 with thermal-induced deformation, we studied the creep deformation of non-twisted Nylon 6 wires and Nylon 6 artificial muscles as functions of annealing temperature. For comparison, we also studied the creep deformation of chicken muscle fibers in a temperature range of 20 to 35 °C. The experimental results showed that we could use the standard linear viscoelastic model to describe the creep deformation of the chicken muscle fibers, the non-twisted Nylon 6 wires, and the Nylon 6 artificial muscles. A simple method was developed to calculate the mechanical (elastic) constants and viscous resistance coefficient (viscosity) of the three different materials. The activation energy for the creep deformation of the chicken muscle fibers in the temperature of 20 to 35 °C was 18.79 kJ/mol. For the non-twisted Nylon 6 wires, the activation energy for the creep deformation was generally larger than that of the chicken muscle fibers, and was dependent on the annealing temperature. For the Nylon 6 artificial muscles, the activation energy for the creep deformation was smaller than that of the chicken muscle fibers.

Effect of ivabradine, a funny current inhibitor, on portal hypertensive rats.

BACKGROUND: Ivabradine is a funny current inhibitor which is administered to patients with congestive heart failure to reduce their heart rate (HR) and attenuate oxidative stress. Chronic liver diseases are characterized by portal hypertension and hyperdynamic circulation with tachycardia. The present study aimed to investigate the effect of ivabradine on portal hypertension. METHODS: Male Sprague-Dawley rats received partial portal vein ligation (PVL) to induce portal hypertension. The PVL rats were randomly allocated to receive either vehicle or ivabradine treatment for 10 days. Then the hemodynamic data were collected. The levels of oxidative stress markers and the mRNA expression of nitric oxide synthase (NOS) were measured in the collateral vessel, the superior mesentery artery and the liver. In addition, the collateral vascular responsiveness to arginine vasopressin (AVP) was examined in the ivabradine-treated and vehicle-treated PVL rats. RESULTS: Treatment with ivabradine significantly lowered the HR (174 ± 20 vs. 374 ± 9 beats/min; p < 0.001) and the superior mesentery arterial flow (SMAf) (6.6 ± 0.3 vs. 9.1 ± 0.7 mL/min/100 g BW; p = 0.005) of the PVL rats compared with the control group. The mean arterial pressure, cardiac index, systemic vascular resistance, portal pressure and serum levels of oxidative stress markers were not significantly affected by ivabradine treatment. In addition, the NOS expression and collateral vascular responsiveness to AVP were not significantly influenced by ivabradine treatment, either. CONCLUSION: Ivabradine reduced the HR and SMAf in PVL rats, which alleviated the hyperdynamic circulatory state and splanchnic hyperemia of portal hypertension. However, whether these effects would help alleviate portal hypertension-related complications requires further clinical investigations.

Cataract Surgery and Rate of Visual Field Progression in Primary Open-Angle Glaucoma.

PURPOSE: To test the hypothesis that cataract surgery slows the apparent rate of visual field (VF) decay in primary open-angle glaucoma patients compared with rates measured during cataract progression. DESIGN: Retrospective cohort study. METHODS: Consecutive open-angle glaucoma patients who underwent cataract surgery and who had ≥4 VFs and ≥3 years of follow-up before and after surgery were retrospectively reviewed. Mean deviation (MD) rate, visual field index (VFI) rate, pointwise linear regression (PLR), pointwise rate of change (PRC), and the Glaucoma Rate Index (GRI) were compared before and after cataract surgery. RESULTS: A total of 134 eyes of 99 patients were included. Median (interquartile range) follow-up was 6.5 (4.7-8.1) and 5.3 (4.0-7.3) years before and after cataract surgery, respectively. All intraocular pressure (IOP) parameters (mean IOP, standard deviation of IOP, and peak IOP) significantly improved (P < .001) after cataract surgery. All VF indices indicated an accelerated VF decay rate after cataract surgery: MD rate (-0.18 ± 0.40 dB/year vs -0.40 ± 0.62 dB/year, P < .001), VFI rate (-0.44% ± 1.09%/year vs -1.19% ± 1.85%/year, P < .001), GRI (-5.5 ± 10.8 vs -13.5 ± 21.5; P < .001), and PRC (-0.62% ± 2.47%/year before and -1.35% ± 3.71%/year after surgery; P < .001) and PLR (-0.20 ± 0.82 dB/year before and -0.42 ± 1.16 dB/year after surgery; P < .001) for all VF locations. Worse baseline MD and postoperative peak IOP were significantly associated with the postoperative VF decay rate and the change in the decay rate after cataract surgery. CONCLUSION: Although all IOP parameters improved after cataract surgery, VFs continued to progress. Cataract surgery does not slow the apparent rate of glaucomatous VF decay as compared to rates measured during the progression of the cataract.

Comparison of simulated keratometric changes following wavefront-guided and wavefront-optimized myopic laser-assisted in situ keratomileusis.

PURPOSE: The aim of the study was to determine and compare the relationship between change in simulated keratometry (K) and degree of refractive correction in wavefront-guided (WFG) and wavefront-optimized (WFO) myopic laser-assisted in situ keratomileusis (LASIK). METHODS: A total of 51 patients were prospectively randomized to WFG LASIK in one eye and WFO LASIK in the contralateral eye at the Byers Eye Institute, Stanford University. Changes in simulated K and refractive error were determined at 1 year post-operatively. Linear regression was employed to calculate the slope of change in simulated K (ΔK) for change in refractive error (ΔSE). The mean ratio (ΔK/ΔSE) was also calculated. RESULTS: The ratio of ΔK to ΔSE was larger for WFG LASIK compared to WFO LASIK when comparing the slope (ΔK/ΔSE) as determined by linear regression (0.85 vs 0.83, p = 0.04). Upon comparing the mean ratio (ΔK/ΔSE), subgroup analysis revealed that ΔK/ΔSE was larger for WFG LASIK for refractive corrections of >3.00 D and >4.00 D (0.89 vs 0.83; p = 0.0323 and 0.88 vs 0.83; p = 0.0466, respectively). Both linear regression and direct comparison of the mean ratio (ΔK/ΔSE) for refractive corrections <4.00 D and >4.00 D revealed no difference in ΔK/ΔSE between smaller and larger refractive corrections. CONCLUSION: WFO LASIK requires a smaller amount of corneal flattening compared to WFG LASIK for a given degree of refractive correction. For both, there was no significant difference in change in corneal curvature for a given degree of refractive error between smaller and larger corrections.

Effect of sirolimus on liver cirrhosis and hepatic encephalopathy of common bile duct-ligated rats.

Cirrhosis is often associated with portal hypertension and portal-systemic collateral vessels formation attributed to angiogenesis, which leads to severe complications as hepatic encephalopathy. Sirolimus has anti-fibrosis and anti-angiogenesis effects, but whether it influences the severity of portal-systemic collaterals and hepatic encephalopathy is unknown. This study was thus designed to address this issue in rats with common bile duct ligation-induced liver cirrhosis. Sham-operated rats were surgical controls. Rats were intraperitoneally administered with 0.5 and 2 mg/kg/day sirolimus or vehicle for 2 weeks. Four weeks post operations, motor activities, body weight, biochemistry and hemodynamic data were measured. The liver was dissected for histopathology, immunohistochemical stains and protein analysis. On the parallel cirrhotic groups, the portal-systemic shunting was determined. The results showed that the body weight gain was significantly lower in sirolimus-treated rats. Sirolimus reduced portal pressure and plasma levels of alanine aminotransferase, aspartate aminotransferase and ammonia, and attenuated hepatic inflammation and fibrosis in cirrhotic rats. In addition, the hepatic phosphorylated mammalian target of rapamycin (mTOR) and P70S6K protein expressions were significantly downregulated and endothelial nitric oxide synthase (eNOS) expression upregulated by sirolimus. Sirolimus did not influence portal-systemic shunting and motor activities of cirrhotic rats. In conclusion, sirolimus significantly improved hepatic inflammation and fibrosis accompanied by portal pressure reduction in cirrhotic rats, in which down-regulated mTOR/P70S6K and up-regulated eNOS expressions might play a role. However, sirolimus did not significantly change the severity of portal-systemic collaterals and motor activities, suggesting that the multifactorial pathogenesis of hepatic encephalopathy could not be fully overcome by sirolimus.

The effects of pioglitazone in cirrhotic rats with hepatopulmonary syndrome.

BACKGROUND: Hepatopulmonary syndrome (HPS) is characterized by oxygen desaturation and increased intrapulmonary shunting formation in cirrhosis. Due to an unclarified mechanism, there is still no effective therapy except liver transplantation. Recent studies revealed that pulmonary angiogenesis may participate in pathogenesis, in which nitric oxide (NO) and vascular endothelial growth factor (VEGF) play roles. Pioglitazone, a peroxisome proliferator-activated receptor gamma agonist, exerts anti-angiogenesis effect. However, whether pioglitazone influences pulmonary angiogenesis, shunting and HPS remains unexplored. METHODS: Cirrhosis with HPS was induced in Spraque-Dawley rats with common bile duct ligation (CBDL). Pioglitazone (10 mg/kg/day, oral gavage) or vehicle was administered from 8th to 28th day post CBDL. On the 28th day, the mortality rate, hemodynamic parameters, concentrations of plasma glucose and liver biochemistry parameters, and arterial blood gas data were evaluated. Lungs were dissected for protein expression analyses. In another series, intrapulmonary shunting degree was determined by color microsphere method in paralleled groups. RESULTS: The survival rates were similar in HPS rats with or without pioglitazone administration. Pioglitazone did not influence the hemodynamic parameters, glucose and liver biochemistry levels, oxygen saturation and alveolar arterial gradient, but significantly down-regulated pulmonary VEGF protein expression, endothelial NO synthase (eNOS) activation, and decreased intrapulmonary shunts. Pioglitazone significantly decreased intrapulmonary shunts as compared with the vehicle (18.1 ± 4.5 vs. 9.8 ± 3.6, p = 0.015). CONCLUSION: Pioglitazone down-regulated VEGF, eNOS and decreased intrapulmonary shunts without improving oxygenation. The current finding suggests a multifactorial mechanism of HPS that could not be successfully overcome merely by pioglitazone-induced anti-angiogenesis and shunting reduction.

Metformin reduces intrahepatic fibrosis and intrapulmonary shunts in biliary cirrhotic rats.

BACKGROUND: Liver fibrosis causes portal hypertension which dilates collateral vasculature and enhances extra-hepatic angiogenesis including intrapulmonary shunts, which subsequently complicates with hepatopulmonary syndrome. Metformin is an anti-diabetic agent which possesses anti-inflammation and anti-angiogenesis properties. This study evaluated the effect of metformin treatment on liver and lung in a non-diabetic rat model with biliary cirrhosis induced via common bile duct ligation (CBDL). METHODS: CBDL rats were fed with metformin 150 mg/kg/day during the 8th-28th day post operation. The hemodynamic and biochemistry parameters were tested, and blood gas analysis was performed. The liver and lung were dissected for protein analysis and immuno-histochemical stains. Intrapulmonary shunting degree was determined using color microsphere method. RESULTS: Metformin treatment neither induced obvious hypoglycemic event nor altered hemodynamics in cirrhotic rats. The plasma levels of alanine aminotransferase were significantly reduced by metformin (control vs. metformin: 269 ± 56 vs. 199 ± 21 IU/L, P = 0.02). Sirius Red stains and CD-68 stains showed that metformin reduced intrahepatic fibrosis and CD-68-positive macrophages. Metformin did not influence hypoxia and intrapulmonary angiogenesis; however, it significantly reduced intrapulmonary shunts (31.7 ± 10.1 vs. 15.0 ± 6.6%, P = 0.006.). Furthermore, metformin reduced the protein expressions of COX-2 and PI3K in liver and COX-1 in lung. CONCLUSION: Metformin reduced liver injury and improved hepatic fibrosis in cirrhotic rats. It also attenuated the intrapulmonary shunts. However, the effects of metformin on pulmonary angiogenesis and hypoxia were insignificant.

Ascorbate lacks significant influence in rats with bile duct ligation-induced liver injury.

BACKGROUND: Liver inflammation may induce fibrogenesis, cirrhosis and portal hypertension. Liver cirrhosis is characterized by increased intrahepatic resistance and enhanced vasoconstrictive response. The splanchnic vasodilatation, angiogenesis and portosystemic collaterals formation further bring about lethal complications. Ascorbate is a potent antioxidant with anti-inflammation, anti-fibrosis, and anti-angiogenesis effects. However, the relevant influences in chronic liver injury have not been sufficiently explored. METHODS: Chronic liver injury was induced in Spraque-Dawley rats with common bile duct ligation (BDL). Ascorbate (250 mg/kg/day, oral gavage) or vehicle was administered starting on the 1st day after operation. On the 8th (hepatitis) and 29th (cirrhosis) day, serum biochemistry parameters, hepatic concentrations of lipid peroxidation-related substances, protein expressions of α-SMA, TGF-ß, iNOS, eNOS, p-eNOS-Ser1177, p-eNOS-Thr496, VEGF, VEGFR2, p-VEGFR2, and liver histology were evaluated. In three series of paralleled groups, rats treated with 28-day ascorbate or vehicle received hemodynamic measurements, hepatic and collateral vasoresponsiveness perfusion experiments, mesenteric CD31 immunofluorescence staining, and Western blot analyses of mesenteric VEGF, VEGFR2, pVEGFR2, PDGF, PDGFß, COX1, COX2, eNOS, p-eNOS-Thr495, p-eNOS-Ser1177 protein expressions. In another series, the severity of portosystemic shunting was evaluated. RESULTS: Ascorbate did not influence hepatitis, oxidative stress, fibrosis, and hemodynamic parameters in BDL rats. The intrahepatic and collateral vasoresponsiveness were not affected, either from direct incubation or acute treatment with ascorbate. Furthermore, the mesenteric angiogenesis and severity of shunting were not influenced. CONCLUSION: The oxidative stress, fibrosis, hemodynamic derangements, angiogenesis and vascular functional changes in BDL-induced chronic liver injury may be too overwhelming to be modulated by ascorbate.

Selective cyclooxygenase inhibition by SC-560 improves hepatopulmonary syndrome in cirrhotic rats.

OBJECTIVE: Hepatopulmonary syndrome (HPS) is characterized by hypoxia in patients with chronic liver disease. The mechanism of HPS includes pulmonary vasodilatation, inflammation, and angiogenesis. Prostaglandins synthesized by cyclooxygenases (COX) participate in vascular responsiveness, inflammation and angiogenesis, which can be modulated by COX inhibitors. We therefore evaluated the impact of COX inhibition in rats with common bile duct ligation (CBDL)-induced liver cirrhosis and HPS. METHODS: Cirrhotic rats were randomly allocated to receive non-selective COX inhibitor (indomethacin), selective COX-1 inhibitor (SC-560), or COX-2 inhibitor (celecoxib) for 14 days. After that, hemodynamic parameters, severity of hypoxia and intrapulmonary shunts, liver and renal biochemistry parameters, histological finding and protein expressions were evaluated. RESULTS: Non-selective COX inhibition by indomethacin improved hepatic fibrosis and pulmonary inflammation in cirrhotic rats with HPS. It also decreased mean arterial blood pressure, portal pressure, and alleviated hypoxia and intrapulmonary shunts. However, indomethacin increased mortality rate. In contrast, selective COX inhibitors neither affected hemodynamics nor increased mortality rate. Hypoxia was improved by SC-560 and celecoxib. In addition, SC-560 decreased intrapulmonary shunts, attenuated pulmonary inflammation and angiogenesis through down-regulating COX-, NFκB- and VEGF-mediated pathways. CONCLUSION: Selective COX-1 inhibitor ameliorated HPS by mitigating hypoxia and intrapulmonary shunts, which are related to anti-inflammation and anti-angiogenesis.

Effects of raloxifene on portal hypertension and hepatic encephalopathy in cirrhotic rats.

Raloxifene, a selective estrogen receptor modulator, has been used extensively for osteoporosis. In addition to the effect of osteoporosis treatment, emerging evidences show that raloxifene affects the vascular function in different tissues. Cirrhosis is characterized with portal hypertension and complicated with hepatic encephalopathy. Portal hypertension affects portal-systemic shunt which leads to hepatic encephalopathy that the vascular modulation might influence severity of hepatic encephalopathy. Herein, we evaluated the impact of raloxifene on bile duct ligation (BDL)-induced cirrhotic rats. The female Sprague-Dawley rats received BDL plus ovariectomy or sham-operation. Four weeks later, rats were divided into 2 subgroups respectively to receive of raloxifene (10mg/kg/day) or saline (vehicle) for 14 days. On the 43th day, motor activities and hemodynamic parameters were measured. Hepatic and vascular mRNA and protein expressions were determined. The histopathological change of liver was examined. We found that the liver biochemistry, ammonia level and motor activity were similar between cirrhotic rats with or without raloxifene administration. The hemodynamic parameters were not significantly different except that raloxifene reduced portal venous inflow. Raloxifene exacerbated hepatic fibrosis and up-regulated hepatic endothelin-1 and cyclooxygenase 2 protein expressions. In addition, raloxifene modulated the mRNA expressions of endothelial nitric oxide synthase, cyclooxygenase and endothelin-1 in the superior mesenteric artery and collateral vessel. In conclusion, raloxifene aggravates hepatic fibrosis and decreases portal venous inflow in cirrhotic rats without adversely affecting portal hypertension and hepatic encephalopathy. The modulation of hepatic and vascular endothelin-1, endothelial nitric oxide synthase and cyclooxygenase expressions may play a role in the mechanism.

Phototherapeutic keratectomy for epithelial basement membrane dystrophy.

PURPOSE: The purpose of this study was to evaluate the long-term efficacy of phototherapeutic keratectomy (PTK) in treating epithelial basement membrane dystrophy (EBMD). METHODS: Preoperative and postoperative records were reviewed for 58 eyes of 51 patients with >3 months follow-up (range 3-170 months) treated for EBMD with PTK after failure of conservative medical treatment at Byers Eye Institute of Stanford University. Symptoms, clinical findings, and corrected distance visual acuity (CDVA) were assessed. The primary outcome measure was symptomatic recurrence as measured by erosions or visual complaints >3 months after successful PTK. RESULTS: For eyes with visual disturbances (n=30), preoperative CDVA was20/32 (0.24 Log-MAR, SD 0.21) and postoperative CDVA was ~20/25 (0.07 LogMAR, SD 0.12; P<0.0001). Twenty-six eyes (86.7%) responded to treatment, with symptomatic recurrence in 6 eyes (23.1%) at an average of 37.7 months (SD 42.8). For eyes with painful erosions (n=29), preoperative CDVA was ~20/25 (0.12, SD 0.19) and postoperative CDVA was ~20/20 (0.05. SD 0.16; P=0.0785). Twenty-three eyes (79.3%) responded to treatment, with symptomatic recurrence in 3 eyes (13.0%) at an average of 9.7 months (SD 1.5). The probability of being recurrence free after a successful treatment for visual disturbances and erosions at 5 years postoperatively was estimated at 83.0% (95% confidence interval 68.7%-97.0%) and 88.0% (95% confidence interval 65.3%-96.6%), respectively. CONCLUSION: The majority of visual disturbances and painful erosions associated with EBMD respond to PTK. For those with a treatment response, symptomatic relief is maintained over long-term follow-up.

Towards unsupervised fluorescence lifetime imaging using low dimensional variable projection.

Analyzing large fluorescence lifetime imaging (FLIM) data is becoming overwhelming; the latest FLIM systems easily produce massive amounts of data, making an efficient analysis more challenging than ever. In this paper we propose the combination of a custom-fit variable projection method, with a Laguerre expansion based deconvolution, to analyze bi-exponential data obtained from time-domain FLIM systems. Unlike nonlinear least squares methods, which require a suitable initial guess from an experienced researcher, the new method is free from manual interventions and hence can support automated analysis. Monte Carlo simulations are carried out on synthesized FLIM data to demonstrate the performance compared to other approaches. The performance is also illustrated on real-life FLIM data obtained from the study of autofluorescence of daisy pollen and the endocytosis of gold nanorods (GNRs) in living cells. In the latter, the fluorescence lifetimes of the GNRs are much shorter than the full width at half maximum of the instrument response function. Overall, our proposed method contains simple steps and shows great promise in realising automated FLIM analysis of large data sets.