Highly efficient capture approach for the identification of diverse inherited retinal disorders

Our study presents a 319-gene panel targeting inherited retinal dystrophy (IRD) genes. Through a multi-center retrospective cohort study, we validated the assay's effectiveness and clinical utility and characterized the mutation spectrum of Taiwanese IRD patients. Between January 2018 and May 2022, 493 patients in 425 unrelated families, all initially suspected of having IRD without prior genetic diagnoses, underwent detailed ophthalmic and physical examinations (with extra-ocular features recorded) and genetic testing with our customized panel. Disease-causing variants were identified by segregation analysis and clinical interpretation, with validation via Sanger sequencing. We achieved a read depth of >200× for 94.2% of the targeted 1.2 Mb region. 68.5% (291/425) of the probands received molecular diagnoses, with 53.9% (229/425) resolved cases. Retinitis pigmentosa (RP) is the most prevalent initial clinical impression (64.2%), and 90.8% of the cohort have the five most prevalent phenotypes (RP, cone-rod syndrome, Usher's syndrome, Leber's congenital amaurosis, Bietti crystalline dystrophy). The most commonly mutated genes of probands that received molecular diagnosis are USH2A (13.7% of the cohort), EYS (11.3%), CYP4V2 (4.8%), ABCA4 (4.5%), RPGR (3.4%), and RP1 (3.1%), collectively accounted for 40.8% of diagnoses. We identify 87 unique unreported variants previously not associated with IRD and refine clinical diagnoses for 21 patients (7.22% of positive cases). We developed a customized gene panel and tested it on the largest Taiwanese cohort, showing that it provides excellent coverage for diverse IRD phenotypes.

Protective effects of compound M01 on retinal ganglion cells in experimental anterior ischemic optic neuropathy by inhibiting TXNIP/NLRP3 inflammasome pathway

Apoptotic death of retinal ganglion cells (RGCs) is a common pathologic feature in different types of optic neuropathy, including ischemic optic neuropathy and glaucoma, ultimately leading to irreversible visual function loss. Potent and effective protection against RGC death is determinative in developing a successful treatment for these optic neuropathies. This study evaluated the neuroprotective effect of a HECT domain-E3 ubiquitin ligase inhibitor, M01, on retinal ganglion cells after ischemic injury. Experimental anterior ischemic optic neuropathy (AION) was induced by photothrombotic occlusion of microvessels supplying optic nerve in rats. M01 was administered (100 mg/Kg and 200 mg/Kg) subcutaneously for three consecutive days after AION induction. Administration of M01 (100 mg/Kg) significantly increased RGC survival and preserved visual function after AION induction. The number of TUNEL-positive cells and ED1-positive cells was significantly decreased, and optic disc edema was reduced considerably after ischemic infarction with M01 treatment. Moreover, M01 effectively ameliorated optic nerve demyelination and enhanced M2 microglial polarization after AION induction. M01 enhanced the expression of nuclear factor erythroid 2-related factor (Nrf2); subsequently, downregulated Thioredoxin interacting protein (TXNIP) expression, inhibited NLR family pyrin domain containing 3 (NLRP3) activation, and further decreased inflammatory factors, interleukin (IL)-1β and IL-6 in the retina after ischemic injury. These findings suggested that M01 has therapeutic potential by modulating Nrf2 and TXNIP/NLRP3 inflammasome pathways in the retina and optic nerve ischemic damage-related diseases.

Gene therapy in hereditary retinal dystrophy

Hereditary retinal dystrophies (HRDs), such as retinitis pigmentosa, Leber's congenital amaurosis (LCA), Usher syndrome, and retinoschisis, are a group of genetic retinal disorders exhibiting both genetic and phenotypic heterogeneity. Symptoms include progressive retinal degeneration and constricted visual field. Some patients will be legal or completely blind. Advanced sequencing technologies improve the genetic diagnosis of HRD and lead to a new era of research into gene-targeted therapies. Following the first Food and Drug Administration approval of gene augmentation therapy for LCA caused by RPE65 mutations, multiple clinical trials are currently underway applying different techniques. In this review, we provide an overview of gene therapy for HRD and emphasize four distinct approaches to gene-targeted therapy that have the potential to slow or even reverse retinal degeneration: (1) viral vector-based and nonviral gene delivery, (2) RNA-based antisense oligonucleotide, (3) genome editing by the Clustered Regularly Interspaced Short Palindromic Repeat/cas9 system, and (4) optogenetics gene therapy.

Prevalence and associated relating factors in patients with hereditary retinal dystrophy: a nationwide population-based study in Taiwan

OBJECTIVE

To investigate the prevalence, incidence and relating factors that are associated with hereditary retinal dystrophy (HRD) in Taiwan from 2000 to 2013.

DESIGN, SETTING AND PARTICIPANTS

This is a nationwide, population-based, retrospective case-control study using National Health Insurance Database. Study groups are patients with HRD as case group; age-matched patients without any diagnosis of HRD as control group. We enrolled 2418 study subjects, of which 403 were HRD patients. Important relating factors such as hypertension, diabetes, coronary artery disease, autoimmune disease, cancer, liver cirrhosis, chronic kidney disease, stroke, hyperlipidaemia, asthma, depression and dementia are also included.

EXPOSURE

Patients diagnosed with HRD were retrieved from National Health Insurance Database.

MAIN OUTCOMES AND MEASURES

OR calculated between the relating factors and HRD for objects and stratified by age and sex group between 2000 and 2013.

RESULTS

Four hundred and three patients were included in the study group and 2015 in the control group. The incidence of HRD was 3.29/100 000, and the prevalence of HRD was 40.5/100 000 persons. The tendency of study group to have more cataract, cystoid macula oedema (CME) as compared with the control group. Among the subgroup with comorbidities, the relating factors such as hypertension, diabetes and chronic kidney disease was significantly higher among HRD patients with age 55 and above.

CONCLUSIONS

74% of the diagnosed HRD are retinitis pigmentosa. Population-based data suggested an increased incidence of cataract in younger patients, whereas older HRD patients are more susceptible to develop CME. Further work is needed to elucidate the mechanism between these ophthalmological disorders and HRD.

The Protective Effects of n-Butylidenephthalide on Retinal Ganglion Cells during Ischemic Injury

Clinically, acute ischemic symptoms in the eyes are one of the main causes of vision loss, with the associated inflammatory response and oxidative stress being the key factors that cause injury. Nonarteritic anterior ischemic optic neuropathy (NAION) is the most common type of ischemic optic neuropathy (ION); however, there are still no effective or safe treatment options to date. In this study, we investigated the neuroprotective effects of n-butylidenephthalide (BP) treatment in an experimental NAION rodent model (rAION). BP (10 mg/kg) or PBS (control group) were administered on seven consecutive days in the rAION model. Rats were evaluated for visual function by flash visual evoked potentials (FVEPs) at 4 weeks after NAION induction. The retina and optic nerve were removed for histological examination after the rats were euthanized. The molecular machinery of BP treatment in the rAION model was analyzed using Western blotting. We discovered that BP effectively improves retinal ganglion cell survival rates by preventing apoptotic processes after AION induction and reducing the inflammatory response through which blood-borne macrophages infiltrate the optic nerve. In addition, BP significantly preserved the integrity of the myelin sheath in the rAION model, demonstrating that BP can prevent the development of demyelination. Our immunoblotting results revealed the molecular mechanism through which BP mitigates the neuroinflammatory response through inhibition of the NF-κB signaling pathway. Taken together, these results demonstrate that BP can be used as an exceptional neuroprotective agent for ischemic injury.

The Effects of Two Nrf2 Activators, Bardoxolone Methyl and Omaveloxolone, on Retinal Ganglion Cell Survival during Ischemic Optic Neuropathy

Nonarteritic anterior ischemic optic neuropathy (NAION) is one of the most common acute optic neuropathies that affect the over 55-year-old population. NAION causes the loss of visual function, and it has no safe and effective therapy. Bardoxolone methyl (methyl 2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oate; CDDO-Me; RTA 402) is a semisynthetic triterpenoid with effects against antioxidative stress and inflammation in neurodegeneration and kidney disease that activates the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway. Moreover, RTA 402 is an FDA-approved compound for the treatment of solid tumors, lymphoid malignancies, melanoma, and chronic kidney disease. Omaveloxolone (RTA 408) is an activator of Nrf2 and an inhibitor of NFκB, possessing antioxidative and anti-inflammatory activities in mitochondrial bioenergetics. RTA 408 is also under clinical investigation for Friedreich ataxia (FA). In this study, a rodent anterior ischemic optic neuropathy (rAION) model induced by photothrombosis was used to examine the therapeutic effects of RTA 402 and RTA 408. Treatment with RTA402 results in antiapoptotic, antioxidative stress, anti-inflammatory, and myelin-preserving effects on retinal ganglion cell (RGC) survival and visual function via regulation of NQO1 and HO-1, reduced IL-6 and Iba1 expression in macrophages, and promoted microglial expression of TGF-β and Ym1 + 2 in the retina and optic nerve. However, these effects were not observed after RTA 408 treatment. Our results provide explicit evidence that RTA 402 modulates the Nrf2 and NFκB signaling pathways to protect RGCs from apoptosis and maintain the visual function in an rAION model. These findings indicate that RTA 402 may a potential therapeutic agent for ischemic optic neuropathy.

Protective Effects of Oroxylin A on Retinal Ganglion Cells in Experimental Model of Anterior Ischemic Optic Neuropathy

Nonarteritic anterior ischemic optic neuropathy (NAION) is the most common cause of acute vision loss in older people, and there is no effective therapy. The effect of the systemic or local application of steroids for NAION patients remains controversial. Oroxylin A (OA) (5,7-dihydroxy-6-methoxyflavone) is a bioactive flavonoid extracted from Scutellariae baicalensis Georgi. with various beneficial effects, including anti-inflammatory and neuroprotective effects. A previous study showed that OA promotes retinal ganglion cell (RGC) survival after optic nerve (ON) crush injury. The purpose of this research was to further explore the potential actions of OA in ischemic injury in an experimental anterior ischemic optic neuropathy (rAION) rat model induced by photothrombosis. Our results show that OA efficiently attenuated ischemic injury in rats by reducing optic disc edema, the apoptotic death of retinal ganglion cells, and the infiltration of inflammatory cells. Moreover, OA significantly ameliorated the pathologic changes of demyelination, modulated microglial polarization, and preserved visual function after rAION induction. OA activated nuclear factor E2 related factor (Nrf2) signaling and its downstream antioxidant enzymes NAD(P)H:quinone oxidoreductase (NQO-1) and heme oxygenase 1 (HO-1) in the retina. We demonstrated that OA activates Nrf2 signaling, protecting retinal ganglion cells from ischemic injury, in the rAION model and could potentially be used as a therapeutic approach in ischemic optic neuropathy.

Age and gender differences for the behavioral phenotypes of 3xTg alzheimer's disease mice

The triple transgenic Alzheimer's disease (3xTg-AD) strain is a common mouse model used for studying the pathology and mechanism of Alzheimer's disease (AD). The 3xTg-AD strain exhibits two hallmarks of AD, amyloid beta (Aβ) and neurofibrillary tangles. Several studies using different gender and age of 3xTg-AD mice to investigate their behavior phenotypes under the influence of various treatments have reported mixed results. Therefore, a comprehensive investigation on the optimal gender, age, and training paradigms used for behavioral studies of 3xTg-AD is necessary. In the present study, we investigated the behavioral phenotypes for the two genders of 3xTg-AD mice at 3, 6, 9, and 12 months old and compared the results with age-, gender-matched C57BL/6N control strain. All mice were subjected to tail flick, pinprick, open field, elevated plus maze, passive avoidance, and trace fear conditioning (TFC) tests to evaluate their sensory, locomotor, anxiety, and learning/memory functions. The results showed that TFC on male 3xTg-AD mice is optimal for studying the memory performance in AD. The sensory and locomotor functions of 3xTg-AD mice for two genders appear to be normal before 6 months, decline in fear memory afterwards. The differences between control and 3xTg-AD male mice in contextual and cued memory are robust, thus they are ideal for evaluating the effect of a treatment. Since it is costly and time consuming to obtain wildtype littermates as controls, C57BL/6N strain is suggested to be used as control mice because their baseline performance of sensorimotor functions are similar to that of 3xTg-AD mice.

Enhanced contextual fear memory in peroxiredoxin 6 knockout mice is associated with hyperactivation of MAPK signaling pathway

Fear dysregulation is one of the symptoms found in post-traumatic stress disorder (PTSD) patients. The functional abnormality of the hippocampus is known to be implicated in the development of such pathology. Peroxiredoxin 6 (PRDX6) belongs to the peroxiredoxin family. This antioxidant enzyme is expressed throughout the brain, including the hippocampus. Recent evidence reveals that PRDX6 plays an important role in redox regulation and the modulation of several signaling molecules involved in fear regulation. Thus, we hypothesized that PRDX6 plays a role in the regulation of fear memory. We subjected a systemic Prdx6 knockout (Prdx6-/-) mice to trace fear conditioning and observed enhanced fear response after training. Intraventricular injection of lentivirus-carried mouse Prdx6 into the 3rd ventricle reduced the enhanced fear response in these knockout mice. Proteomic analysis followed by validation of western blot analysis revealed that several proteins in the MAPK pathway, such as NTRK2, AKT, and phospho-ERK1/2, cPLA2 were significantly upregulated in the hippocampus of Prdx6-/- mice during the retrieval stage of contextual fear memory. The distribution of PRDX6 found in the astrocytes was also observed throughout the hippocampus. This study identifies PRDX6 as a participant in the regulation of fear response. It suggests that PRDX6 and related molecules may have important implications for understanding fear-dysregulation associated disorders like PTSD.

The 4-(Phenylsulfanyl) butan-2-one Improves Impaired Fear Memory Retrieval and Reduces Excessive Inflammatory Response in Triple Transgenic Alzheimer's Disease Mice

Alzheimer's disease (AD) is a neurodegenerative disease characterized by an excessive inflammatory response and impaired memory retrieval, including spatial memory, recognition memory, and emotional memory. Acquisition and retrieval of fear memory help one avoid dangers and natural threats. Thus, it is crucial for survival. AD patients with impaired retrieval of fear memory are vulnerable to dangerous conditions. Excessive expression of inflammatory markers is known to impede synaptic transmission and reduce the efficiency of memory retrieval. In wild-type mice, reducing inflammation response can improve fear memory retrieval; however, this effect of this approach is not yet investigated in 3xTg-AD model mice. To date, no satisfactory drug or treatment can attenuate the symptoms of AD despite numerous efforts. In the past few years, the direction of therapeutic drug development for AD has been shifted to natural compounds with anti-inflammatory effect. In the present study, we demonstrate that the compound 4-(phenylsulfanyl) butan-2-one (4-PSB-2) is effective in enhancing fear memory retrieval of wild-type and 3xTg-AD mice by reducing the expression of TNF-α, COX-2, and iNOS. We also found that 4-PSB-2 helps increase dendritic spine density, postsynaptic density protein-95 (PSD-95) expression, and long-term potentiation (LTP) in the hippocampus of 3xTg-AD mice. Our study indicates that 4-PSB-2 may be developed as a promising therapeutic compound for treating fear memory impairment of AD patients.

4-(Phenylsulfanyl) Butan-2-One Attenuates the Inflammatory Response Induced by Amyloid-β Oligomers in Retinal Pigment Epithelium Cells

Age-related macular degeneration (AMD) is a progressive eye disease that causes irreversible impairment of central vision, and effective treatment is not yet available. Extracellular accumulation of amyloid-beta (Aβ) in drusen that lie under the retinal pigment epithelium (RPE) has been reported as one of the early signs of AMD and was found in more than 60% of Alzheimer’s disease (AD) patients. Extracellular deposition of Aβ can induce the expression of inflammatory cytokines such as IL-1β, TNF-α, COX-2, and iNOS in RPE cells. Thus, finding a compound that can effectively reduce the inflammatory response may help the treatment of AMD. In this research, we investigated the anti-inflammatory effect of the coral-derived compound 4-(phenylsulfanyl) butan-2-one (4-PSB-2) on Aβ_1-42 oligomer (oAβ_1-42) added to the human adult retinal pigment epithelial cell line (ARPE-19). Our results demonstrated that 4-PSB-2 can decrease the elevated expressions of TNF-α, COX-2, and iNOS via NF-κB signaling in ARPE-19 cells treated with oAβ_1-42 without causing any cytotoxicity or notable side effects. This study suggests that 4-PSB-2 is a promising drug candidate for attenuation of AMD.

[Application of the China-PAR stroke risk equations in a rural northern Chinese population]

OBJECTIVE

To validate five-year risk prediction models for stroke in a contemporary rural Northern Chinese population.

METHODS

Totally 6 483 rural adults aged 40 to 79 years without cardiovascular diseases were enrolled at baseline between June and August 2010, and followed up through January 2017. Expected prediction risk using the China-PAR (prediction for atherosclerotic cardiovascular disease risk in China) stroke risk equations were compared with the new Framingham stroke risk profile (FSRP). The recalibrated models were applied by adjusting the five-year baseline survival rate and the mean score to our rural northern Chinese population, while keeping other coefficient parameters the same as the original models. Kaplan-Meier analysis was used to obtain the observed event (nonfatal or fatal stroke) rate for the five years, and the expected-observed ratios were calculated to evaluate overestimation or underestimation in the cohort. The models were assessed by discrimination C statistic, calibration χ², and calibration charts and plots for illustration as well.

RESULTS

Over an average of (5.83 ± 1.14) years of the follow-up in this validation cohort with 6 483 rural Chinese participants, 438 subjects deve-loped a first stroke event. Recalibrated China-PAR stroke risk equations and FSRP well-performed for predicting five-year stroke risk in men, and had C statistics of 0.709 (95%CI, 0.675 - 0.743) and 0.721 (95%CI, 0.688 - 0.754), with calibration χ² values being 5.7 (P = 0.770) and 13.6 (P = 0.137), respectively. However, both China-PAR and FSRP overestimated stroke events by 11.6% and 30.0% in women, and had C statistics of 0.713 (95%CI, 0.684-0.743) and 0.710 (95%CI, 0.679-0.740), respectively. Calibration χ² values in women were 12.5 (P = 0.188) for China-PAR and 24.0 (P = 0.004) for FSRP. In addition, the calibration charts and plots illustrated good agreement between the observations and the predictions only in the China-PAR stroke risk equations, especially for men.

CONCLUSION

In this validation cohort of rural northern Chinese adults, the China-PAR models had better performance of five-year stroke risk prediction than the FSRP, indicating that recalibrated China-PAR stroke risk equations might be appropriate tools for risk assessment and primary prevention of stroke in China.

Optic nerve head width and retinal nerve fiber layer changes are proper indexes for validating the successful induction of experimental anterior ischemic optic neuropathy

Reproducible skills are essential for successful induction of a rat model of anterior ischemic optic neuropathy (rAION). We established an in vivo validation index by measuring the natural course of optic nerve head (ONH) width and retinal nerve fiber layer (RNFL) thickness in the rAION model using optical coherence tomography (OCT). The rAION model was induced by photodynamic operations. We measured the ONH width, RNFL, Inner Plexiform layer (IPL) and Ganglion cell complex (GCC) thickness in the acute stage (<3 days), subacute stage (day-7 to day-14) and later stage (day-14 to day-28) post-infarct by OCT. Retinal layers were measured by hematoxylin and eosin stain (HE) to confirm the OCT findings. The RGCs survival rate was determined by retrograde Fluoro-gold labeling, and the visual function was assessed with flash visual-evoked potentials (FVEPs) 4 weeks post-infarct. We observed significant thinning in GCC, IPL, and RNFL at day-14 and day-28 but only RNFL showed significant thinning between day-14 and day-28. The ONH showed significant swelling in the acute stage which correlated at a greater extent with RNFL than GCC and IPL. Further RNFL correlated at a greater extent at with GCC than IPL. HE-stained retina cross sections also showed IPL and RNFL thinning, which further confirmed our OCT findings. The RGC density and P1-N2 amplitude were significantly reduced in rAION. Our data suggest that Swelling, reduction of swelling, and atrophy of RNFL in acute, sub-acute, and later stage, respectively and ONH swelling in the acute stage are essential events for confirming the successful induction of rAION.

[Experimental observation on the effect of bone marrow mesenchymal stem cells transplanting CXCR4 over gentamicin ototoxicity]

Objective:To observe the survival and migration ability of CXCR4-BMSCs in guinea pig cochlea with gentamycin induced sensorineural hearing loss, and to explore whether SDF-1/CXCR4 axis can mediate bone marrow mesenchymal stem cells (BMSCs) to cochlear homing.Method:BMSCs were isolated and extracted from guinea pigs. A bone marrow mesenchymal stem cell line with overexpression of CXCR4 was established. The animal model of sensorineural deafness was established by intraperitoneal injection of gentamicin［100 mg/(kg·d)］in 50 healthy guinea pigs. The successful deafness animals were randomly divided into three groups(14 rats in each group): sterilizing water group, BMSCs transplantation group and CXCR4-BMSCs transplantation group.Auditory brainstem response(ABR) were performed at 2 weeks and 4 weeks respectively after the tansplantation through cochlear tympanic pathway. The directional homing of the implanted cells in the cochlea was traced by the frozen section fluorescence of the cochlear tissue.Result:The hearing thresholds of the three groups were (91.3±5.2),(90.7±4.8)and (90.9±5.6)dB (SPL) respectively. There was no significant difference among them(P>0.05). In sterile Water group, the hearing thresholds were(89.7±6.4)dB and (89.2±6.7)dB respectively when detected on 2 and 4 weeks after transplantation. There were no significant difference(P>0.05);In BMSCs group, the hearing thresholds were (88.6±5.3)dB(SPL) on 2 weeks and (78.4±7.3)dB(SPL) on 4 weeks after transplantation. In CXCR4-BMSCs group, the hearing thresholds were(75.3±7.8)dB(SPL) on 2 weeks and (62.1±8.4)dB(SPL) on 4 weeks after transplantation. The differences were statistically significant (PThe hearing threshold was (75.3±7.8)dB (SPL) at 2 weeks after operation. The hearing enhancement was about 15 dB, the hearing threshold was (62.1±8.4)dB(SPL) at 4 weeks, the difference was statistically significant(P<0.05).Fluorescence tracing showed that the number of CXCR4-BMSCs homing cells was significantly increased, and showed a cohort like arrangement.Conclusion:The SDF-1/CXCR4 axis plays an important role in the directional homing and differentiation of the cells into the cochlea, which can improve the hearing repair ability of guinea pigs induced by gentamicin induced sensorineural deafness.

[Progress in research of family-based cohort study on common chronic non-communicable diseases in rural population in northern China]

Family-based cohort study is a special type of study design, in which biological samples and environmental exposure information of the member in a family are collected and related follow up is conducted. Family-based cohort study can be applied to explore the effect of genetic factors, environmental factors, gene-gene interaction, and gene-environment interaction in the etiology of complex diseases. This paper summarizes the objectives, methods and results, as well as the opportunities and challenges of the family-based cohort study on common chronic non-communicable diseases in rural population in northern China.

Soluble P-selectin promotes retinal ganglion cell survival through activation of Nrf2 signaling after ischemia injury

Retinal ischemic injuries play an important role in the pathogenesis of several eye disorders. Inflammation and oxidative stress are key players in ischemic injuries. Following retinal ischemia, vascular endothelial cells and leukocytes express several inflammatory adhesion receptors, such as selectins and cell adhesion molecules. P-selectin stimulates leukocyte recruitment to platelet aggregates and has an important role in vascular homeostasis and inflammatory leukocyte extravasation. Soluble P-selectin can be neuroprotective through competitive binding to the receptors of endogenous P-selectin molecules. Here, we demonstrate the neuroprotective effect of a recombinant P-selectin immunoglobin G (P-sel-IgG) chimeric fusion protein in a rat anterior ischemic optic neuropathy (rAION) model. rAION was induced by photodynamic therapy. P-sel-IgG treatment reduced optic nerve edema and stabilized the blood-optic nerve barrier (BONB) in the acute phase of rAION. Further, P-sel-IgG increased the retinal ganglion cell (RGC) survival rate, reduced RGC apoptosis, preserved visual function, maintained retinal nerve fiber layer thickness, and reduced macrophage infiltration in optic nerve tissue in the chronic phase (day 28). Increased NAD(P)H quinone dehydrogenase 1 (NQO1) and heme oxygenase 1(HO-1) expression levels, along with increased transcription factor Nrf2, suggesting an antioxidant role of P-sel-IgG via the Nrf2 signaling pathway. In conclusion, this study is the first to demonstrate that P-sel-IgG treatment promotes RGC survival by stabilizing the BONB and activating the Nrf2 signaling pathway in a rAION model.

Oroxylin A promotes retinal ganglion cell survival in a rat optic nerve crush model

Purpose

To investigate the effect of oroxylin A on the survival of retinal ganglion cells (RGC) and the activation of microglial cells in a rat optic nerve (ON) crush model.

Methods

Oroxylin A (15mg/Kg in 0.2ml phosphate-buffered saline) or phosphate-buffered saline (PBS control) was immediately administered after ON crush once by subcutaneous injection. Rats were euthanized at 2 weeks after the crush injury. The density of RGC was counted by retrograde labeling with FluoroGold and immunostaining of retina flat mounts for Brn3a. Electrophysiological visual function was assessed by flash visual evoked potentials (FVEP). TUNEL assay, immunoblotting analysis of glial fibrillary acidic protein (GFAP), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in the retinas, and immunohistochemistry of GFAP in the retinas and ED1 in the ON were evaluated.

Results

Two weeks after the insult, the oroxylin A-treated group had significantly higher FG labeled cells and Brn3a+ cells suggesting preserved RGC density in the central and mid-peripheral retinas compared with those of the PBS-treated group. FVEP measurements showed a significantly better preserved latency of the P1 wave in the ON-crushed, oroxylin A-treated rats than the ON-crushed, PBS treated rats. TUNEL assays showed fewer TUNEL positive cells in the ON-crushed, oroxylin A-treated rats. The number of ED1 positive cells was reduced at the lesion site of the optic nerve in the ON-crushed, oroxylin A-treated group. Increased GFAP expression in the retina was reduced greatly in ON-crushed, oroxylin A-treated group. Furthermore, administration of oroxylin A significantly attenuated ON crush insult-induced iNOS and COX-2 expression in the retinas.

Conclusions

These results demonstrated that oroxylin A hasss neuroprotective effects on RGC survival with preserved visual function and a decrease in microglial infiltration in the ONs after ON crush injury.

Growth under elevated air temperature alters secondary metabolites in Robinia pseudoacacia L. seedlings in Cd- and Pb-contaminated soils

Plant secondary metabolites play a pivotal role in growth regulation, antioxidant activity, pigment development, and other processes. As the global climate changes, increasing atmospheric temperatures and contamination of soil by heavy metals co-occur in natural ecosystems, which alters the pH of rhizosphere soil and influences the bioavailability and mobility of metals. Elevated temperatures in combination with heavy metals are expected to affect plant secondary metabolites, but this issue has not been extensively examined. Here, we investigated secondary metabolites in Robiniapseudoacacia seedlings exposed to elevated temperatures using a passive warming device in combination with Cd- and Pb-contaminated soils. Heavy metals significantly stimulated the accumulation of saponins, phenolic compounds, and flavonoids in leaves and stems; alkaloid compounds increased in leaves and decreased in stems, and condensed tannins fluctuated. Elevated temperatures, alone and in combination with Cd and Pb, caused increases in secondary metabolites in the plant tissues. Phenolic compounds showed the greatest changes among the secondary metabolites and significant interactive effects of temperature and metals were observed. These results suggest that slightly elevated temperature could enhance protective and defense mechanisms of Robinia pseudoacacia seedlings exposed to heavy metals by stimulating the production of secondary metabolites.

Neuroprotective effect of 4-(Phenylsulfanyl)butan-2-one on optic nerve crush model in rats

This study is to investigate the effect of coral-related compound, 4-(phenylsulfanyl)butan-2-one (4-PSB-2) on optic nerves (ON) and retinal ganglion cells (RGC) in a rat model subjected to ON crush. The ONs of adult male Wistar rat (150-180 g) were crushed by a standardized method. The control eyes received a sham operation. 4-PSB-2 (5 mg/kg in 0.2 mL phosphate-buffered saline) or phosphate-buffered saline (PBS control) was immediately administered after ON crush once by subcutaneous injection. Rats were euthanized at 2 weeks after the crush injury. RGC density was counted by retrograde labeling with FluoroGold (FG) application to the superior colliculus, and visual function was assessed by flash visual evoked potentials (FVEP). TUNEL assay, immunoblotting analysis of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2) in the retinas, and immunohistochemistry of ED1 in the ON were evaluated. Two weeks after the insult, the RGC densities in the central and mid-peripheral retinas in ON-crushed, 4-PSB-2-treated rats were significantly higher than that of the corresponding ON-crushed, PBS-treated rats FVEP measurements showed a significantly better preserved latency of the P1 wave in the ON-crushed, 4-PSB-2-treated rats than the ON-crushed, PBS treated rats. TUNEL assays showed fewer TUNEL positive cells in the ON-crushed, 4-PSB-2-treated rats. The number of ED1 positive cells was reduced at the lesion site of the optic nerve in the ON-crushed, 4-PSB-2-treated group. Furthermore, administration of 4-PSB-2 significantly attenuated ON crush insult-stimulated iNOS and COX2 expression in the retinas. These results demonstrated that 4-PSB-2 protects RGCs and helps preserve the visual function in the rat model of optic nerve crush. 4-PSB-2 may work by being anti-apoptotic and by attenuation of the inflammatory responses involving less ED1 positive cells infiltration in ON as well as suppression of iNOS/COX-2 signaling pathway in the retinas to rescue RGCs after ON crush injury.

The interaction of serum testosterone levels and androgen receptor CAG repeat polymorphism on the risk of erectile dysfunction in aging Taiwanese men

Testosterone has been found to play important roles in men's sexual function. However, the effects of testosterone can be modulated by androgen receptor (AR) CAG repeat polymorphism. It could also contribute to the risk of erectile dysfunction (ED). The aim of this study is to evaluate the interaction of serum testosterone levels and AR CAG repeat polymorphism on the risk of ED in aging Taiwanese men. This cross-sectional data of Taiwanese men older than 40 years were collected from a free health screening held between August 2010 and August 2011 in Kaohsiung city, Taiwan. All participants completed a health questionnaires included five-item version of the International Index of Erectile Function (IIEF-5) and the International Prostate Symptoms Score, received a detailed physical examination and provided 20 cm3 whole blood samples for biochemical and genetic evaluation. The IIEF-5 was used to evaluate ED. Serum albumin, total testosterone (TT), and sex hormone-binding globulin levels were measured. Free testosterone level was calculated. AR gene CAG repeat polymorphism was determined by direct sequencing. Finally, 478 men with the mean age of 55.7 ± 4.8 years were included. When TT levels were above 330 ng/dL, the effect of testosterone level on erectile function seemed to reach a plateau and a significantly negative correlation between AR CAG repeat length and the score of IIEF-5 was found (r = -0.119, p = 0.034). After adjusting for other covariates, the longer AR CAG repeat length was still an independent risk factor for ED in subjects with TT above 330 ng/dL (p = 0.006), but not in TT of 330 ng/dL or below. In conclusion, both serum testosterone levels and AR CAG repeat polymorphism can influence erectile function concomitantly. In subjects with normal TT concentration, those with longer AR CAG repeat lengths have a higher risk of developing ED.

Ethambutol induces impaired autophagic flux and apoptosis in the rat retina

Ethambutol (EMB), an effective first-line antituberculosis agent, can cause serious visual impairment or irreversible vision loss in a significant number of patients. However, the mechanism underlying this ocular cytotoxicity remains to be elucidated. In this study, we found that there were statistically significant dose- and time-dependent increases in the number of cytoplasmic vacuoles and the level of cell death in EMB-treated RGC-5 cells (retinal ganglion cells). The protein kinase C (PKC)δ inhibitor rottlerin markedly reduced the EMB-induced activation of caspase-3 and the subsequent apoptosis of RGC-5 cells. Western blot analysis revealed that the expression levels of class III PI3K, Beclin-1, p62 and LC3-II were upregulated, and LC3 immunostaining results showed activation of the early phase and inhibition of the late stage of autophagy in retinas of the EMB-intraperitoneal (IP)-injected rat model. We further demonstrated that exposure to EMB induces autophagosome accumulation, which results from the impaired autophagic flux that is mediated by a PKCδ-dependent pathway, inhibits the PI3K/Akt/mTOR signaling pathway and leads to apoptotic death in retina neuronal cells. These results indicate that autophagy dysregulation in retinal neuronal cells might play a substantial role in EMB-induced optic neuroretinopathy.

Summary: This study provides the first evidence that EMB induces autophagosome accumulation, which results from the impaired autophagic flux that is mediated by a PKCδ-dependent pathway, and leads to apoptotic death in retina neuronal cells.

First Report of Lasiodiplodia theobromae Associated with Stem Canker of Cassia fistula in Guangxi, South China

Cassia fistula, a member of the Fabaceae, known as the golden shower tree, is native to South Asia. It is now distributed worldwide and is popular as an ornamental plant as well as being used in herbal medicine. In October 2013, symptoms of stem canker were observed on C. fistula in a nursery (108°38' E, 22°87' N) in Nanning, Guangxi, China. The symptoms began as small brown lesions, which enlarged over several months to long, striped, slightly sunken lesions, 1 to 9 cm in width and 16 to 135 cm in length. The conspicuous cankers had vertical cracks outlining the canker and evenly spaced horizontal cracks, eventually resulting in whole plants dying back. The cankers were found on 90% of six-year-old plants in this nursery and were also observed in other plantings. On potato dextrose agar (PDA), isolates with similar morphological characteristics were consistently recovered from symptomatic plant tissues after surface sterilization in 75% ethanol for 30 sec and then in 0.1% mercuric chloride for 2 min. Over 100 conidia were examined from three isolates and were found to be elliptical and hyaline when immature, becoming dark brown, one-septate, and longitudinally striate when mature and ranging from 20 to 31 × 11 to 16 μm (average 25.5 × 13.6 μm). The rDNA internal transcribed spacer (ITS) region of isolate LC-1 was sequenced (GenBank Accession No. KM387285), and it showed 100% identity to Lasiodiplodia theobromae (Pat.) Griffon & Maubl. (GenBank KC964548), confirming the morphological identification (2) as L. theobromae (also known as Botryosphaeria rhodina (Cooke) Arx). A culture of this isolate has been preserved in the Guangxi Academy of Agricultural Sciences fungal collection. The pathogenicity of the isolate was tested on healthy twigs and branches of C. fistula trees in a field setting at Guangxi Agricultural Vocational-Technical College, Nanning, Guangxi, in June and August 2014. For each treatment, five green twigs and five 2-year-old branches were used. Five adjacent needle punctures were made on each branch with a sterilized needle. A mycelial plug was then placed on the wound of each branch and wrapped with Parafilm. Control twigs were treated with sterile PDA plugs. One week later, typical lesions were observed on the inoculated branches, with symptoms becoming more extensive after two weeks, but no symptoms were seen on the controls. Koch's postulates were fulfilled by re-isolation of L. theobromae from diseased branches. L. theobromae is recognized as an important wood pathogen and has been reported to cause cankers, dieback, and fruit and root rots in over 500 different hosts, including perennial fruit and nut trees, vegetable crops, and ornamental plants (2). The fungus has been reported on C. fistula in India since the 1970s (1); however, to our knowledge, this is the first report of L. theobromae infecting C. fistula in China. References: (1) R. S. Mathur. The Coelomycetes of India. Bishen Singh Mahendra Pal Singh, Delhi, India, 1979. (2) J. R. Úrbez-Torres et al. Plant Dis. 92:519, 2008.

Cytoprotective effects of fisetin against hypoxia-induced cell death in PC12 cells

Fisetin protects cells under hypoxia through ROS scavenging and the HIF1α-, MAPK/ERK-, p38 MAPK- and PI3 K/Akt-dependent pathways in PC12 cells.

Efficacy of granulocyte-colony stimulating factor treatment in a rat model of anterior ischemic optic neuropathy

Non-arteritic anterior ischemic optic neuropathy (NA-AION) is the most common cause of acute ischemic damage to the optic nerve (ON), and the leading cause of seriously impaired vision in people over 55 years of age. It demonstrated that subcutaneous administration of Granulocyte colony-stimulating factor (G-CSF) reduces RGC death in an ON crush model in rats, and that the neuroprotective effects may involve both anti-apoptotic and anti-inflammatory processes. Our recent work shows that the protective actions of G-CSF in rAION models may involve both anti-apoptotic and anti-inflammatory processes. However, the exact rescuing mechanisms involved in the administration of G-CSF in rAION models need further investigation. In addition, further studies on the administration of G-CSF at different time intervals after the induction of rAION may be able to illustrate whether treatment given at a later time is still neuroprotective. Further, it is unknown whether treatment using G-CSF combined with other drugs will result in a synergistic effect in a rAION model. Inflammation induced by ischemia plays an essential role on the ON head in NA-AION, which can result in disc edema and compartment changes. Therefore, it is reasonable that adding an anti-inflammatory drug may enhance the therapeutic effects of G-CSF. An ongoing goal is to evaluate the novel sites of action of both G-CSF and other anti-inflammatory drugs, and to identify the functionally protective pathways to enhance RGC survival. These investigations may open up new therapeutic avenues for the treatment of ischemic optic neuropathy.

Neuroprotective effects of recombinant human granulocyte colony-stimulating factor (G-CSF) in a rat model of anterior ischemic optic neuropathy (rAION)

The purpose of this study was to investigate the neuroprotective effects of recombinant human granulocyte colony stimulating factor (G-CSF), as administered in a rat model of anterior ischemic optic neuropathy (rAION). Using laser-induced photoactivation of intravenously administered Rose Bengal in the optic nerve head of 60 adult male Wistar rats, an anterior ischemic optic neuropathy (rAION) was inducted. Rats either immediately received G-CSF (subcutaneous injections) or phosphate buffered saline (PBS) for 5 consecutive days. Rats were euthanized at 4 weeks post infarct. Density of retinal ganglion cells (RGCs) was counted using retrograde labeling of Fluoro-gold. Visual function was assessed by flash visual-evoked potentials (FVEP) at 4 weeks. TUNEL assay in the retinal sections and immunohistochemical staining of ED1 (marker of macrophage/microglia) were investigated in the optic nerve (ON) specimens. The RGC densities in the central and mid-peripheral retinas in the G-CSF treated rats were significantly higher than those of the PBS-treated rats (survival rate was 71.4% vs. 33.2% in the central retina; 61.8% vs. 22.7% in the mid-peripheral retina, respectively; both p < 0.05). FVEP measurements showed a significantly better preserved latency and amplitude of the p1 wave in the G-CSF-treated rats than that of the PBS-treated rats (latency120 ± 11 ms vs. 142 ± 12 ms, p = 0.03; amplitude 50 ± 11 μv vs. 31 ± 13 μv, p = 0.04). TUNEL assays showed fewer apoptotic cells in the retinal ganglion cell layers of G-CSF treated rats [2.1 ± 1.0 cells/high power field (HPF) vs. 8.0 ± 1.5/HPF; p = 0.0001]. In addition, the number of ED1 positive cells was attenuated at the optic nerve sections of G-CSF-treated rats (16 ± 6/HPF vs. 35 ± 10/HPF; p = 0.016). In conclusion, administration of G-CSF is neuroprotective in the rat model of anterior ischemic optic neuropathy, as demonstrated both structurally by RGC density and functionally by FVEP. G-CSF may work via the dual actions of anti-apoptosis for RGC surviving as well as anti-inflammation in the optic nerves as evidenced by less infiltration of ED1-povitive cells.

First Report of Leaf Spot Disease Caused by Glomerella magna on Lobelia chinensis in China

Lobelia chinensis is a perennial herbaceous plant in the family Campanulaceae that is native to China, where it grows well in moist to wet soils. It is commonly used as a Chinese herbal medicine. In May 2012, symptoms of leaf spot were observed on leaves of L. chinensis in Nanning, Guangxi Zhuang Autonomous Region, China. The leaf lesions began as small, water-soaked, pale greenish to grayish spots, which enlarged to gray to pale yellowish spots, 4 to 6 mm in diameter. At later stages, numerous acervuli appeared on the lesions. Acervuli were mostly epiphyllous, and 40 to 196 μm in diameter. On potato dextrose agar (PDA), a fungus was consistently recovered from symptomatic leaf samples, with a 93% isolation rate from 60 leaf pieces that were surface sterilized in 75% ethanol for 30 s and then in 0.1% mercuric chloride for 45 s. Three single-spore isolates were used to evaluate cultural and morphological characteristics of the pathogen. Setae were two to three septate, dark brown at the base, acicular, and up to 90 μm long. Conidia were long oblong-elliptical, guttulate, hyaline, and 11 to 20 × 4.1 to 6.3 μm (mean 15.2 × 5.1 μm). These morphological characteristics of the fungus were consistent with the description of Colletotrichum magna (teleomorph Glomerella magna Jenkins & Winstead) (1). The rDNA internal transcribed spacer (ITS) region of one isolate, LC-1, was sequenced (GenBank Accession No. KC815123), and it showed 100% identity to G. magna, GenBank HM163187.1, an isolate from Brazil cultured from papaya (2). Although KC815123 was identified as G. magna, it shows 99% identity to GenBank sequences from isolates of C. magna, and more research is needed to elucidate the relationships between these taxa, especially with consideration to host specificity. Pathogenicity tests were performed with each of the three isolates by spraying conidial suspensions (1 × 10⁶ conidia/ml) containing 0.1% Tween 20 onto the surfaces of leaves of 30-day-old and 6- to 8-cm-high plants. For each isolate, 30 leaves from five replicate plants were treated. Control plants were treated with sterilized water containing 0.1% Tween 20. All plants were incubated for 36 h at 25°C and 90% relative humidity in an artificial climate chamber, and then moved into a greenhouse. Seven days after inoculation, gray spots typical of field symptoms were observed on all inoculated leaves, but no symptoms were seen on water-treated control plants. Koch's postulates were fulfilled by reisolation of G. magna from diseased leaves. To our knowledge, this is the first report of G. magna infecting L. chinensis worldwide. References: (1) M. Z. Du et al. Mycologia 97:641, 2005. (2) R. J. Nascimento et al. Plant Dis. 94:1506, 2010.

First-principles study: size-dependent optical properties for semiconducting silicon carbide nanotubes

Using first-principles calculations, we investigate the effect of tube size on optical properties of the zigzag, armchair, and chiral SiC nanotubes. The results indicate that the optical spectra of SiC nanotubes are dependent on the diameter and chirality, and that optical anisotropy is observed for different light polarizations. For a given chirality of SiCNTs, redshifts or blueshifts of the peaks in the dielectric function and energy loss function with increasing tube diameter are possible due to the competition between the size effect and pi orbitals overlapping, and the shifts become smaller as the tube diameter increases. The unusual optical properties of semiconducting SiC nanotubes present an opportunity for applications in electro-optical devices.

The application of stem cells in the treatment of ischemic diseases

Ischemia causes oxygen deprivation, cell injury and related organ dysfunction. Although ischemic injury may be local, it involves many biochemical changes in different cell types. The ability of stem cells to differentiate into different cell lineages provides the possibility of their use in treating a variety of diseases requiring tissue repair or reconstitution, such as stroke, ischemic retinopathy, myocardial infarction, ischemic disorders of the liver, ischemic renal failure, and ischemic limb dysfunction. Several cell types including embryonic stem cells, various progenitor and stem cells of hematopoietic or mesenchymal origin have been used in attempts to reconstitute injured tissue. Xenologous or autologous stem cells may be administered either through the peripheral vascular system or directly by regional injection. The stem cells are then guided to the infarct site by homing signals. Either by cell differentiation or paracrine effects, stem cells or progenitor cells participate in the reconstruction of a favorable microenvironment resulting in neovascularization and tissue regeneration that eventually improve the physiological function of organs with ischemic damage.

Correlations of androgen deficiency with clinical symptoms in Taiwanese males

The purpose of this study was to elucidate correlations between different biochemical measurements of androgen deficiency and clinical symptoms in male residents of Taiwan. An investigation of the serum biochemical markers for androgen deficiency in 650 males, including total testosterone, calculated free testosterone, and bioavailable testosterone, was conducted. Measurements of clinical symptoms were obtained using a questionnaire of the androgen deficiency in the aging male (ADAM) by St Louis University (SLQ). Correlations among the biochemical markers, correlations of the biochemical markers and age, and relationships between the biochemical markers and the SLQ were evaluated. The sensitivity and specificity of the SLQ were determined. Bioavailable and calculated free testosterone correlated better with age than did total testosterone. Eighty percent of the men had a positive SLQ, and 20% had a negative SLQ. The percentage of positive SLQ results increased with age. No statistically significant difference was noted between the biochemical markers of bioavailable and calculated free testosterone levels and the SLQ status except for men aged over 70 years. The SLQ in this study showed an acceptable sensitivity of about 80%, but the specificity was poor (about 20%). In conclusion, bioavailable testosterone and calculated free testosterone were more-closely correlated with age and may be better biochemical markers for androgen deficiency. SLQ might not be a suitable single measurement for androgen deficiency and should be used together with biochemical markers.

A seroepidemiology study of varicella among children aged 0-12 years in Taiwan

The epidemiology pattern of varicella appears to vary among regions with different climates, population densities, and degrees of development. This study investigated the age-specific varicella zoster virus (VZV) seroprevalence in children aged 0 to 12 years in Taiwan and compared these seroprevalences between free and private vaccination areas. Residual sera were collected from 13 hospitals with 1,401 valid samples. Immunoglobulin G antibodies to VZV were measured by enzyme-linked immunosorbent assay. Parents of 656 children answered questions about the varicella incidence and varicella vaccination history of their children. In the 8-12 year-olds, the seroprevance ranged between 88.0-93.8% in northern, central, and eastern, while it was only 76.1% in southern Taiwan. The seroprevalence of children 0-5 years old were significantly different between free and private vaccination areas. Seropositive children who reported no history of varicella or receiving varicella vaccine accounted for 26.1-59.3% of the total positive cases. Our findings suggest the possible effects of climate, geographical conditions, and lifestyle on the seroepidemiology of VZV in Taiwan. The efforts of implementing a varicella vaccination program in Taiwan should focus on reaching high levels of coverage.

Intraocular gene transfer of ciliary neurotrophic factor rescues photoreceptor degeneration in RCS rats

Ciliary neurotrophic factor (CNTF) is known as an important factor in the regulation of retinal cell growth. We used both recombinant CNTF and an adenovirus carrying the CNTF gene to regulate retinal photoreceptor expression in a retinal degenerative animal, Royal College of Surgeons (RCS) rats. Cells in the outer nuclear layer of the retinae from recombinant-CNTF-treated, adenoviral-CNTF-treated, saline-operated, and contralateral untreated preparations were examined for those exhibiting CNTF photoreceptor protective effects. Cell apoptosis in the outer nuclear layer of the retinae was also detected. It was found that CNTF had a potent effect on delaying the photoreceptor degeneration process in RCS rats. Furthermore, adenovirus CNTF gene transfer was proven to be better at rescuing photoreceptors than that when using recombinant CNTF, since adenoviral CNTF prolonged the photoreceptor protection effect. The function of the photoreceptors was also examined by taking electroretinograms of different animals. Adenoviral-CNTF-treated eyes showed better retinal function than did the contralateral control eyes. This study indicates that adenoviral CNTF effectively rescues degenerating photoreceptors in RCS rats.

Comparison of hand-assisted laparoscopic nephroureterectomy with open surgery for upper urinary tract tumor

Herein we report on our initial experience in performing nephroureterectomy by hand-assisted laparoscopic surgery, and compare the results with those performed by traditional open methods. From December 2000 to September 2001, 10 patients with upper urinary tract tumors underwent hand-assisted laparoscopic nephroureterectomy. Except for one patient who required elective conversion to open surgery due to renal vein injury, this cohort of 9 patients was compared to a group of 35 patients who had received traditional open nephroureterectomy over the last 2 years. Demographic, intraoperative and postoperative data were compared retrospectively. These two groups were similar in age, body mass index, operation time and time to postoperative oral intake. However, the hand-assisted laparoscopy group was found to have significantly less blood loss, less need for parenteral narcotic and a shorter length of time needed for postoperative hospitalization than the open group. Thus, in this report we have demonstrated hand-assisted laparoscopic nephroureterectomy to be a safe and efficacious treatment of malignant urinary collecting tumors. We believe the benefits of this minimally invasive surgery make it a viable alternative technique for management of upper urinary tract tumor.

Estimating the total number of alleles using a sample coverage method

Previously reported methods for estimating the number of different alleles at a single locus in a population have not described a useful general result. Using the number of alleles observed in a sample gives an underestimate for the true number of alleles. The similar problem of estimating the number of species in a population was first investigated in 1943. In this article we use the sample coverage method proposed by Chao and Lee in 1992 to estimate the number of alleles in a population when there are unequal allele frequencies. Simulation studies under the recurrent mutation model show that, for reasonable sample sizes, a significantly better estimate of the true number can be obtained than that using only the observed alleles. Results under the stepwise mutation model and infinite-allele model are presented. Possible applications include improving the characterization of the prior distribution for the allele frequencies, adjusting the estimates of genetic diversity, and estimating the range of microsatellite alleles.

Color Doppler sonography for ventral hernias in patients with acute abdomen: preliminary findings

PURPOSE

We assessed the usefulness of color Doppler sonography (CDUS) in evaluating the vascular status of ventral hernias and distinguishing incarcerated from nonincarcerated ventral hernias.

METHODS

In this prospective study, 10 patients who presented with acute abdomen and had ventral hernias underwent CDUS from August 1999 to May 2000. Patient age and sex and the clinical severity, mode of therapy, and outcome in these 10 patients were evaluated in relationship to the CDUS findings.

RESULTS

Five patients had readily visible flow in the bowel within the hernial sac on CDUS. Two of these 5 had spontaneous reduction under conservative treatment, and 3 had asymptomatic ventral hernias with acute abdomen caused by spontaneous bacterial peritonitis. Barely visible flow was visualized in the bowel by CDUS in 4 other patients. Three of these underwent emergency surgery because of peritoneal signs; 2 of them were found to have ischemic changes in the bowel. The fourth patient underwent a successful manual reduction. The remaining patient had absent flow in the bowel on CDUS and underwent emergency surgery, which revealed gangrenous changes in the bowel.

CONCLUSIONS

The intensity of the Doppler signals on CDUS appears to be a promising predictor of bowel viability in cases of ventral hernia. Thus, CDUS should impact the determination of the treatment plan, including whether to provide conservative treatment or surgery.

Dickkopf1 is required for embryonic head induction and limb morphogenesis in the mouse

Dickkopf1 (Dkk1) is a secreted protein that acts as a Wnt inhibitor and, together with BMP inhibitors, is able to induce the formation of ectopic heads in Xenopus. Here, we show that Dkk1 null mutant embryos lack head structures anterior of the midbrain. Analysis of chimeric embryos implicates the requirement of Dkk1 in anterior axial mesendoderm but not in anterior visceral endoderm for head induction. In addition, mutant embryos show duplications and fusions of limb digits. Characterization of the limb phenotype strongly suggests a role for Dkk1 both in cell proliferation and in programmed cell death. Our data provide direct genetic evidence for the requirement of secreted Wnt antagonists during embryonic patterning and implicate Dkk1 as an essential inducer during anterior specification as well as a regulator during distal limb patterning.

Separation of stilbenes by capillary electrophoresis and high-performance liquid chromatography

Stilbenes, fluorescence whitening agents (FWAs), are usually added to cleaning agents in household and in industry. Capillary electrophoresis (CE) was often applied to separate various compounds simultaneously for its multinomial advantages. In this paper, we established analytical methods of six diaminostilbenes with CE and ion-pair chromatography (IPC). The optimum mobile phase for IPC was 11.78 mM tetrabutylammonium hydrogen sulfate (TBA) aqueous and acetonitrile. An IPC method has been developed for simple and direct separation for diaminostilbenes, anionic substances, with TBA as ion-pair reagent. Satisfactory linear ranges (7.0 x 10(-3) approximately 3.0 x 10 microg/mL), correlation coefficients (0.9992-0.9999), and detection limits (6-13 ng/mL) were obtained. Separations were also performed by capillary zone electrophoresis (CZE) using a buffer consisting of Tris (pH 10.1), n-tetradecyltrimethylammonium bromide (TTAB) and acetonitrile. A linear range of 5.0 x 10(-1) - 4.0 x 10 microg/mL, correlation coefficients between 0.9975 and 0.9998, and detection limits between 337 and 446 ng/mL were obtained. In particular, the separation of a pair of similar compounds (mass difference of 2) was achieved by addition of TTAB. The optimum analytical methods of CE and high-performance liquid chromatography (HPLC) were applied to commercial household with direct analysis and standard addition. No significant bias were shown between them by t-test at 95% confidence level.

Obstructive jaundice caused by hepatocellular carcinoma: detection by endoscopic sonography

Tumor thrombus in the extrahepatic biliary tree is a rare mechanism of obstructive jaundice. We present a patient with a minute hepatocellular carcinoma in the caudate lobe that invaded the common hepatic duct and caused biliary obstruction. Endoscopic sonography showed a tumor thrombus with central echogenicity and a "nodule-in-nodule" pattern and suggested the correct diagnosis.

Adrenal cyst--a case report

Adrenal cysts are rare and mostly silent clinically. Herein we report a case of adrenal cyst. A 55-year-old female was incidentally found to have a left suprarenal cystic lesion with a calcified wall by abdominal sonography during a work-up for her epigastralgia and left flank pain. Then, computed tomography (CT) revealed a left adrenal cystic mass with wall calcification, magnetic resonance imaging (MRI) showed left retroperitoneal cystic mass with fluid content, and angiography demonstrated an avascular lesion. Surgical exploration was performed via a flank incision and a calcified cystic adrenal mass was excised. The pathologic diagnosis was adrenal pseudocyst with calcified wall. We discuss the diagnosis and management of adrenal cyst and briefly review the literature.

Gray-scale and color Doppler sonographic diagnosis of epiploic appendagitis

Depending on its location, epiploic appendagitis may mimic nearly any acute abdominal condition. We present the case of a patient with left lower quadrant pain. Sonography demonstrated an ovoid, hyperechoic, noncompressible lesion at the point of tenderness but no inflammatory changes in the adjacent colonic wall. Color Doppler sonography showed no flow in the lesion. Based on the sonographic diagnosis of epiploic appendagitis, conservative treatment was given, with complete recovery in 5 days. Awareness of these sonographic findings may aid in the early diagnosis of epiploic appendagitis and avoid unnecessary treatment.

Targeted disruption of the Kcnq1 gene produces a mouse model of Jervell and Lange-Nielsen Syndrome

KCNQ1 encodes KCNQ1, which belongs to a family of voltage-dependent K(+) ion channel proteins. KCNQ1 associates with a regulatory subunit, KCNE1, to produce the cardiac repolarizing current, I(Ks). Loss-of-function mutations in the human KCNQ1 gene have been linked to Jervell and Lange-Nielsen Syndrome (JLNS), a disorder characterized by profound bilateral deafness and a cardiac phenotype. To generate a mouse model for JLNS, we created a line of transgenic mice that have a targeted disruption in the Kcnq1 gene. Behavioral analysis revealed that the Kcnq1(-/-) mice are deaf and exhibit a shaker/waltzer phenotype. Histological analysis of the inner ear structures of Kcnq1(-/-) mice revealed gross morphological anomalies because of the drastic reduction in the volume of endolymph. ECGs recorded from Kcnq1(-/-) mice demonstrated abnormal T- and P-wave morphologies and prolongation of the QT and JT intervals when measured in vivo, but not in isolated hearts. These changes are indicative of cardiac repolarization defects that appear to be induced by extracardiac signals. Together, these data suggest that Kcnq1(-/-) mice are a potentially valuable animal model of JLNS.

Correlation of histologic subtypes and replication error phenotype with comparative genomic hybridization in gastric cancer

To characterize phenotypic and genotypic changes in gastric cancer (GC), DNA copy number aberrations (CNAs) were assessed in 53 tumors using comparative genomic hybridization (CGH) and correlated with clinicopathologic characteristics and status of TP53 and replication error (RER). The number of CNAs per tumor was 6.8 (gain 5.3, loss 1.5), and the number of changes was significantly higher in tumors with advanced stage, TP53 mutation, and without RER than in those with early stage (7.7 vs. 3.0), no TP53 mutations (12.4 vs. 4.8) or RER phenotype (8.2 vs. 2.6). Frequent abnormalities included gains on chromosomal arms 8q (43%), 6q (26%), 11q (26%), 13q (24%), 7p (23%), 17q (23%), and 20q (23%), and losses on chromosomal arms 16q (26%), 19p (23%), 5q (19%), 3p (15%), 4q(15%), and 1p (15%). Advanced GC demonstrated a higher prevalence of gains of 8q (51% vs. 10%, P < 0.05) and loss of 16q (33% vs. 0%, P < 0.05) than early GC. Gains on 8q (64% vs. 20%, P < 0.05), 17q (39% vs. 4%, P < 0.05) and losses on 3p (25% vs. 4%, P = 0.05) and 5q (32% vs. 4%, P < 0.05) were higher in intestinal GC than in diffuse GC. On the other hand, gains on 13q were more common in the diffuse type (40% vs. 11%, P < 0.05). As compared with noncardia cancer, cardia cancer showed more gains on 7p (58% vs. 12%, P < 0.05) and 20q (58% vs. 12%, P < 0.05) and more losses on 4q (50% vs. 5%, P < 0.05). The finding of histology-related aberrations and the combination of CGH and molecular data thus provide additional evidence suggesting genetic heterogeneity of GC.

Adult Wilms' tumor associated with polycythemia--a case report

Both Wilms' tumor (nephroblastoma) in adults and polycythemia in Wilms' tumor are rare. Herein we report an extremely rare case of adult Wilms' tumor associated with polycythemia. A 41-year-old female was incidentally found to have right renal mass by abdominal sonography in a routine health examination. Laboratory examination revealed polycythemia (hemoglobin 20.2 g/dL). Although physical examination was unremarkable, CT scan revealed an homogeneous mass at the middle pole of right kidney, and chest x-ray revealed no metastatic lesions. Right radical nephrectomy was performed smoothly. Grossly, the tumor of 5 x 4.5 x 4.5 cm in size was well circumscribed, and had no vascular structure or collecting system involvement. Microscopic features were consistent with adult nephroblastoma. The post-operative course was uneventful. At follow-up, the patient was well, showed no evidence of recurrence and her hemoglobin level had returned to normal (hemoglobin 14.5 g/dl). We suggest that the relationship between polycythemia and Wilms' tumor should be carefully evaluated before surgical treatment.

Correlation of histologic subtypes and replication error phenotype with comparative genomic hybridization in gastric cancer

To characterize phenotypic and genotypic changes in gastric cancer (GC), DNA copy number aberrations (CNAs) were assessed in 53 tumors using comparative genomic hybridization (CGH) and correlated with clinicopathologic characteristics and status of TP53 and replication error (RER). The number of CNAs per tumor was 6.8 (gain 5.3, loss 1.5), and the number of changes was significantly higher in tumors with advanced stage, TP53 mutation, and without RER than in those with early stage (7.7 vs. 3.0), no TP53 mutations (12.4 vs. 4.8) or RER phenotype (8.2 vs. 2.6). Frequent abnormalities included gains on chromosomal arms 8q (43%), 6q (26%), 11q (26%), 13q (24%), 7p (23%), 17q (23%), and 20q (23%), and losses on chromosomal arms 16q (26%), 19p (23%), 5q (19%), 3p (15%), 4q(15%), and 1p (15%). Advanced GC demonstrated a higher prevalence of gains of 8q (51% vs. 10%, P < 0.05) and loss of 16q (33% vs. 0%, P < 0.05) than early GC. Gains on 8q (64% vs. 20%, P < 0.05), 17q (39% vs. 4%, P < 0.05) and losses on 3p (25% vs. 4%, P = 0.05) and 5q (32% vs. 4%, P < 0.05) were higher in intestinal GC than in diffuse GC. On the other hand, gains on 13q were more common in the diffuse type (40% vs. 11%, P < 0.05). As compared with noncardia cancer, cardia cancer showed more gains on 7p (58% vs. 12%, P < 0.05) and 20q (58% vs. 12%, P < 0.05) and more losses on 4q (50% vs. 5%, P < 0.05). The finding of histology-related aberrations and the combination of CGH and molecular data thus provide additional evidence suggesting genetic heterogeneity of GC.

A large upstream region is not necessary for gene expression or hypersensitive site formation at the mouse beta -globin locus

Developmental expression at the beta-globin locus is regulated in part by the locus control region, a region upstream of the genes containing at least five major DNase I hypersensitive sites (HSs) in mammalian erythrocytes. Sequences farther 5' of these HSs are conserved in mouse and human, and both loci are embedded within a cluster of functional odorant receptor genes. In humans, distant upstream sequences have been implicated in regulation of the beta-globin genes. In this study, the role of the 5'-most HSs and their adjacent sequence was investigated by deletion of an 11-kb region from the mouse locus, including 5'HS 4.2, 5'HS 5, 5'HS 6, and the 5'beta1 odorant receptor gene. Mice that were homozygous for this deletion were fully viable, and no significant effect on adult beta-globin gene expression was seen. 5'HSs 1-4, which are located downstream of the deletion, were still present in the mutant mice. In addition, two new upstream HSs, HS -60.7 and HS -62.5, were found in erythroid tissue of both wild-type and mutant mice. Therefore, although the possibility of a minor role still exists, neither the HSs nor the other regions deleted in this study are essential for beta-globin gene expression, and it is unlikely that chromatin structure is affected either upstream or downstream of the deletion. This is the largest deletion at the mouse locus control region to show no apparent phenotype, and focuses attention on the possible contribution of sequences even farther upstream.

Urgent endoscopic nasobiliary drainage without fluoroscopic guidance: A useful treatment for critically ill patients with biliary obstruction

BACKGROUND

Endoscopic nasobiliary drainage (ENBD) is routinely performed under fluoroscopic control. This is a report of our experience with urgent ENBD without fluoroscopic guidance in critically ill patients.

METHODS

Twenty-six critically ill patients who underwent urgent ENBD for biliary obstruction were analyzed. ENBD was performed without fluoroscopic control because of high risk of transportation or inaccessibility of the x-ray facilities. A pig-tailed nasobiliary catheter was inserted into the bile duct with the help of a guidewire under endoscopic control to bypass the site of obstruction. Successful placement was confirmed by free flow of bile on aspiration via the nasobiliary catheter.

RESULTS

A nasobiliary catheter was successfully placed in 23 patients (88%). Adequate bile drainage was achieved in 20 patients with an overall success rate of 77%. There were no procedure-related complications. The mortality rate for patients with successful biliary drainage was 10% (2 of 20), in contrast to 83% (5 of 6) for the group in which drainage was unsuccessful.

CONCLUSIONS

Urgent ENBD is effective for patients with biliary obstruction. With experience, this procedure may be successfully performed in critically ill patients without fluoroscopic guidance at primary care hospitals or intensive care units where fluoroscopic facilities are not readily available.

Adrenal myelolipoma--report of two cases

Adrenal myelolipoma, which is composed of hematopoietic and adipose elements, is a rare benign tumor. Most adrenal myelolipomas are asymptomatic and are found incidentally. We report two cases of adrenal myelolipoma. One was a middle-aged woman with right flank pain. Tumor size increased 8 years later. The other patient was a 63-year-old man presenting with right flank soreness. The right adrenal tumor was found by abdominal sonography. Both of them received adrenalectomy to relieve symptoms and the pathologic results showed adrenal myelolipoma. The clinical, radiologic and pathologic characteristics of these two cases are discussed together with a review of the literature.