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1.
Retina ; 43(9): e55-e56, 2023 09 01.
Article in English | MEDLINE | ID: mdl-37263183
2.
Article in English | MEDLINE | ID: mdl-37104718

ABSTRACT

PURPOSE: To report the incidence of opacification in a consecutive series of 10 eyes that underwent scleral fixated Akreos AO60 placement with concurrent or subsequent contact with gas or silicone oil. METHODS: Consecutive case series. RESULTS: Three cases of IOL opacification were noted. Two cases of opacification occurred in patients that underwent subsequent retinal detachment repair with C3F8 and one with silicone oil. One patient underwent explanation of the lens due to visually significant opacification. CONCLUSION: Scleral fixation of the Akreos AO60 IOL is associated with risk of IOL opacification when exposed to intraocular tamponade. While surgeons should consider the risk of opacification in patients at high risk of requiring intraocular tamponade, only 1 in 10 patients developed IOL opacification significant enough to require explantation.

3.
Ophthalmic Surg Lasers Imaging Retina ; 53(11): 612-618, 2022 11.
Article in English | MEDLINE | ID: mdl-36378615

ABSTRACT

BACKGROUND AND OBJECTIVES: To explore the incidence of adverse events after bilateral same-day intravitreal 0.7-mg dexamethasone implant (SDIDI) injections. MATERIALS AND METHODS: We performed an IRB approved, single-center, retrospective review of patients receiving bilateral SDIDI injections from January 1, 2016 to October 31, 2021 and reviewed adverse events that occurred within 3 months of injection. RESULTS: A total of 206 bilateral (412 eyes) SDIDI injections were performed in 59 patients. Ocular hypertension or the addition of intraocular pressure (IOP) lowering drops occurred in 121 (29.4%) eyes after IDI. Two (0.5%) eyes required glaucoma drainage surgeries. Of the 117 phakic eyes, 32 (27.4%) had progression of cataract or cataract extraction. There were two (0.5%) episodes of vitreous hemorrhage and one (0.2%) retinal tear with retinal detachment. There were no cases of endophthalmitis. CONCLUSION: Serious complication rates after bilateral same-day IDI injections appears low. Increased IOP that requires intervention can occur. [Ophthalmic Surg Lasers Imaging Retina 2022;53:612-618.].


Subject(s)
Glaucoma , Macular Edema , Humans , Macular Edema/diagnosis , Macular Edema/drug therapy , Macular Edema/etiology , Dexamethasone/adverse effects , Intravitreal Injections , Glucocorticoids/adverse effects , Drug Implants/adverse effects , Visual Acuity , Intraocular Pressure , Glaucoma/etiology , Retrospective Studies
4.
Ophthalmic Surg Lasers Imaging Retina ; 53(9): 502-505, 2022 09.
Article in English | MEDLINE | ID: mdl-36107622

ABSTRACT

BACKGROUND AND OBJECTIVE: The purpose of this article is to determine if outcomes in patients presenting with retinal tears with bridging vessels (BVs) differ from those without BVs. PATIENTS AND METHODS: A case control study of all patients presenting with retinal tears during a 3-year period was completed. Comparisons were made between patients with and without BVs. Variables included vitreous hemorrhage (VH) at presentation, delayed VH, initial and final visual acuity, need for surgery, and retinal detachment. RESULTS: There was a significant increase in the number of patients with a VH at presentation (75% vs 28%; P < .0001), delayed VH (31% vs 7.5%; P = .001), and incidence of pars plana vitrectomy (16% vs 1.3%; P = .002) in the BV cohort. There was no significant difference in time to VH (9.4 vs 38.8 days; P = .32) or final visual acuity (20/25 vs 20/25; P = .45) between the two groups. CONCLUSIONS: The presence of a BV is an important prognostic indicator for risk of delayed VH. Documenting the presence of a BV allows for appropriate patient counseling. [Ophthalmic Surg Lasers Imaging Retina 2022;53:502-505.].


Subject(s)
Retinal Perforations , Case-Control Studies , Humans , Incidence , Retinal Perforations/diagnosis , Retinal Perforations/epidemiology , Retinal Perforations/etiology , Retrospective Studies , Vitreous Hemorrhage/diagnosis , Vitreous Hemorrhage/epidemiology , Vitreous Hemorrhage/etiology
5.
Retina ; 42(11): 2046-2050, 2022 11 01.
Article in English | MEDLINE | ID: mdl-35982506

ABSTRACT

PURPOSE: To determine the efficacy of the 360-degree endolaser (360EL) versus focal laser during primary vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD) repair. METHODS: A single-site retrospective chart review was performed on 241 patients who underwent PPV for primary RRD. Patients were assigned to two groups, PPV with 360EL (n = 183) and PPV without 360EL (n = 59). Only cases where surgeons performed 360EL on all RRDs or surgeons who never perform 360EL on RRDs were included. RESULTS: The single surgery anatomical success rate in the 360EL group was 90.2% compared with 86.5% with focal laser ( P = 0.619). Epiretinal membrane formation in 360EL group at 1 year was 44.4% versus 37% with focal laser ( P = 0.429). Cystoid macular edema formation within 1 year of surgery was 25.8% in 360EL group versus 11.9% with focal laser ( P = 0.04). CONCLUSION: The use of 360EL in PPV for RRD repair does not improve single-surgery anatomical success in routine RRDs when compared with PPV with focal laser.


Subject(s)
Retinal Detachment , Humans , Retinal Detachment/surgery , Retrospective Studies , Visual Acuity , Vitrectomy , Retina/surgery , Treatment Outcome
6.
J Vitreoretin Dis ; 6(2): 104-110, 2022.
Article in English | MEDLINE | ID: mdl-37008666

ABSTRACT

Purpose: This work describes characteristics of pentosan polysulfate sodium (PPS)-associated maculopathy and its similarities with common maculopathies in a retina practice cohort. Methods: Thirty-two patients were identified through electronic medical record query who were exposed to PPS. One patient was excluded for lack of retinal imaging. Thirty-one patients (62 eyes) were included. A retrospective review was used to obtain patient characteristics, examination findings, and retinal imaging of the study patients. Classification into "likely," "unlikely," or "possible" to have PPS-associated maculopathy groups was based on the fundus photography and retinal imaging. Main outcome measures were best-corrected visual acuity, age, sex, diagnosis of reason for referral, allocation into designated maculopathy group, and presence of choroidal neovascularization. Results: Of 31 patients (62 eyes), the median age was 70 years (range, 24-104 years) and the majority were women (87%). Mean best-corrected visual acuity was 0.3 ± 0.4 logMAR at presentation. The most common reason for referral was age-related macular degeneration (29%). Maculopathy grades were "likely" (29%, 9 total patients), "possible" (26%, 8 total patients), or "unlikely" (45%, 14 total patients). Choroidal neovascularization was noted in 9.7% of all eyes and 11% of eyes in the "likely" group. The "possible" and "likely" groups had older ages of presentation (P < .05) compared with the "unlikely" group. Conclusions: A high percentage (55%) of patients with a history of chronic PPS exposure showed features of "likely" or "possible" maculopathy. Similarities with common maculopathies such as age-related macular degeneration and the importance of screening and recognizing at-risk patients are highlighted.

7.
Ophthalmol Retina ; 2(7): 654-658, 2018 07.
Article in English | MEDLINE | ID: mdl-31047373

ABSTRACT

PURPOSE: To analyze comparatively the effect of different intravitreal injection (IVI) protocols on the incidence of endophthalmitis occurring after injection. DESIGN: Retrospective case-control series. PARTICIPANTS: Twenty-seven retina specialists in a large vitreoretinal practice performed 37 646 IVIs. METHODS: Multivariate analysis was used to identify risk factors for development of endophthalmitis occurring after injection. Before all injections, a technician applied 5% povidone-iodine (PI) to the eyelids and conjunctiva. There were 4 distinct aseptic protocols with regard to reapplication of PI by physicians: physicians who did not reapply PI, reapplication of PI without the use of a lid speculum, reapplication of PI before speculum placement, and reapplication of PI after speculum placement. Other analyzed variables included the use of gloves, a caliper to mark the injection site, and the class of medication (steroid vs. anti-vascular endothelial growth factor). MAIN OUTCOME MEASURES: Cases of presumed infectious endophthalmitis. RESULTS: Thirty-three cases of presumed infectious endophthalmitis occurred after 37 646 injections (0.088%). The method of PI application was found to be a statistically significant predictor of the incidence of endophthalmitis (P = 0.031). When compared with the incidence of endophthalmitis for physicians who did not reapply PI (0.124% [20/16 155]), there was no statistical difference for reapplication of PI without the use of a speculum (0.110% [6/5472]; P = 0.584) or reapplication before speculum insertion (0.122% [5/4067]; P = 0.863). However, reapplication of PI after insertion of the lid speculum was associated with a significantly decreased incidence of endophthalmitis (0.017% [2/11 952]; P = 0.004; odds ratio, 0.113). Use of gloves (P = 0.119) or a caliper to mark the injection site (P = 0.496) and the class of medication (P = 0.740) were not found to be statistically significant risk factors for endophthalmitis development. CONCLUSIONS: The application of PI after placement of the lid speculum reduced the incidence of endophthalmitis occurring after injection approximately 7-fold compared with other aseptic protocols. Preventing the eyelid from contacting the injection site after the final application of PI is an important step in improving the safety of intravitreal injections.

8.
Ophthalmic Surg Lasers Imaging Retina ; 48(6): 488-492, 2017 06 01.
Article in English | MEDLINE | ID: mdl-28613355

ABSTRACT

BACKGROUND AND OBJECTIVES: Postoperative retinal folds are a rare complication of retinal detachment repair. Folds involving the macula may result in decreased vision, metamorphopsia, and diplopia. There is no consensus on whether symptomatic folds require additional surgery, as both spontaneous regression and permanent vision loss have been described. The authors present three cases of symptomatic macular folds that demonstrated spontaneous resolution and identify key OCT prognostic signs. PATIENTS AND METHODS: The study presented is a retrospective case series. RESULTS: Three patients developed symptomatic postoperative macular folds. Despite funduscopic appearances indistinguishable from full-thickness folds, optical coherence tomography (OCT) imaging revealed that none of the folds involved the full thickness of the retina. All cases demonstrated spontaneous resolution with evidence of visual improvement within 2 months. CONCLUSION: OCT is essential in distinguishing between partial and full-thickness macular folds. The authors propose that partial-thickness folds should be termed "pseudo-folds," which represent a unique entity that has a favorable natural history. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:488-492.].


Subject(s)
Macula Lutea/pathology , Ophthalmoscopy/methods , Postoperative Complications/diagnosis , Retinal Detachment/surgery , Tomography, Optical Coherence/methods , Vitrectomy/adverse effects , Diagnosis, Differential , Follow-Up Studies , Humans , Male , Middle Aged , Retinal Diseases/diagnosis , Retinal Diseases/etiology , Retrospective Studies
9.
J Ophthalmol ; 2017: 6950642, 2017.
Article in English | MEDLINE | ID: mdl-28596918

ABSTRACT

PURPOSE: Aerobic exercise has been found to be neuroprotective in animal models of retinal degeneration. This study aims to report physical activity levels in patients with RP and investigate the relationship between physical activity and vision-related quality-of-life (QOL). MATERIALS AND METHODS: A retrospective study of adult patients with RP examined in 2005-2014. Physical activity levels were assessed using the Godin Exercise Questionnaire. The NEI-Visual Function Questionaire-25 (VFQ-25), SF-36 General Health survey, and Pepper Assessment Tool for Disability (PAT-D) were administered. RESULTS: 143 patients participated. 81 (56.6%) patients were classified as "active" and 62 (43.4%) as "insufficiently active" by Godin score. VFQ-25 revealed statistically significant differences between the active and insufficiently active patients, including overall visual function (53.3 versus 45.1, p = 0.010), color vision (73.8 versus 52.9, p < 0.001), and peripheral vision (34.3 versus 23.8, p = 0.021). The physical component of the SF-36 and the PAT-D survey also demonstrated statistically significant differences (47.2 versus 52.9, p = 0.002; 24.3 versus 30.0, p = 0.010). Active patients had a higher initial Goldmann visual field (GVF) score (74.8 versus 60.1 degrees, p = 0.255) and final GVF score (78.7 versus 47.1 degrees, p = 0.069) but did not reach statistical significance. CONCLUSIONS: In RP, increased physical activity is associated with greater self-reported visual function and QOL.

10.
J Glaucoma ; 26(4): 311-314, 2017 Apr.
Article in English | MEDLINE | ID: mdl-26859357

ABSTRACT

PURPOSE: To compare sequential glaucoma drainage device (GDD) implantation with transscleral diode cyclophotocoagulation (CPC) following failure of a primary GDD. MATERIALS AND METHODS: A retrospective review of all patients who underwent GDD implantation at a single institution over 10 years. Patients who required an additional GDD and/or CPC were analyzed. Success was defined as absence of loss of light perception, reoperation for glaucoma, and intraocular pressure (IOP) >21 or <6 at 2 consecutive visits after an initial 3-month period. RESULTS: Thirty-two patients received sequential GDD. Twenty-one underwent CPC. Cohorts were statistically similar in regards to age, sex, race, and number of previous surgeries. Preoperatively, the GDD cohort had a lower IOP and better visual acuity. The mean length of follow-up was 37.9 months for the GDD group and 46.3 months for CPC. Both procedures significantly reduced IOP; however, CPC led to a greater reduction (P=0.0172). Survival analysis found the 5-year probability of surgical success to be 65.3% for sequential GDD and 58.0% for CPC (P=0.8678). No cases of phthisis occurred in either group. There were 2 cases of endophthalmitis (6.3%) in the GDD group, and none in the CPC group. In eyes without preexisting corneal edema, estimated corneal decompensation probability at 3 years was 31.6% for GDD and 6.7% for CPC (P=0.0828). CONCLUSIONS: Sequential GDD and CPC are both effective at reducing IOP following the failure of a primary GDD. CPC after GDD failure warrants further investigation as it led to a greater reduction in IOP with fewer serious adverse events.


Subject(s)
Glaucoma Drainage Implants , Glaucoma/surgery , Light Coagulation , Prosthesis Implantation/methods , Aged , Ciliary Body/surgery , Corneal Edema , Endophthalmitis , Female , Glaucoma/physiopathology , Humans , Intraocular Pressure/physiology , Male , Middle Aged , Ocular Hypotension/surgery , Reoperation/methods , Retrospective Studies , Treatment Failure , Visual Acuity/physiology
11.
J AAPOS ; 20(2): 166-8, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26988775

ABSTRACT

We report a case of diffuse bilateral retinal and optic nerve sheath hemorrhages in an 8-week-old boy who was found unresponsive. The child underwent prolonged cardiopulmonary resuscitation and was noted on admission to have a coagulopathy. An autopsy determined the cause of death to be a myocardial infarct in the distribution of an anomalous coronary artery. This case demonstrates the difficulty that may occur in establishing whether child abuse caused death in the setting of another potential cause of mortality.


Subject(s)
Cardiopulmonary Resuscitation , Disseminated Intravascular Coagulation/diagnosis , Myocardial Infarction/diagnosis , Retinal Hemorrhage/diagnosis , Cause of Death , Fatal Outcome , Heart Arrest/diagnosis , Humans , Infant , Male , Tomography, X-Ray Computed
12.
Retin Cases Brief Rep ; 10(3): 267-72, 2016.
Article in English | MEDLINE | ID: mdl-26584329

ABSTRACT

PURPOSE: To report the variability and progression of clinical presentation in three family members with spinocerebellar ataxia Type 7 including early recognizable features on retinal imaging and magnetic resonance imaging. METHODS: Retrospective case series. RESULTS: The proband, Patient 1 (mother) presented at age 26 with light perception vision. Initial examination was significant for optic disc pallor, vascular attenuation, and central macular atrophy. Two years later, her vision declined to no light perception, and fundus examination demonstrated marked progression of macular atrophy and peripheral bone spicule formation. Seven years after the onset of vision loss, neurologic examination demonstrated ataxia, dysarthria, and slowed saccades. Genetic testing of ATXN7 identified heterozygous 61-CAG trinucleotide repeat expansion confirming the diagnosis of spinocerebellar ataxia Type 7. Patient 2 (son) presented at age 11 with visual acuity of 20/300 bilaterally and decreased color vision. Funduscopic examination was notable for disc pallor, vascular attenuation, and peripheral pigmentary changes. Electroretinography demonstrated diminished rod and cone function, and Goldmann visual field testing revealed paracentral scotoma. Patient 3 (daughter) presented at age 14 with visual acuity of 20/50 bilaterally and minimal funduscopic changes. The only significant ophthalmic finding was retinal thinning with atrophy of the outer nuclear layer and subfoveal ellipsoid zone on optical coherence tomography. Early cerebellar volume loss was also noted on magnetic resonance imaging. CONCLUSION: The clinical presentation of spinocerebellar ataxia Type 7 can vary widely even within the same family. In individuals with vision loss and normal fundus examination, careful evaluation of optical coherence tomography and brain magnetic resonance imaging facilitates early diagnosis and genetic testing.


Subject(s)
Retinal Degeneration/pathology , Spinocerebellar Ataxias/physiopathology , Adolescent , Adult , Child , Disease Progression , Female , Humans , Male , Multimodal Imaging , Retinal Degeneration/diagnostic imaging , Retinal Degeneration/physiopathology , Retrospective Studies
13.
Retina ; 36(7): 1388-94, 2016 Jul.
Article in English | MEDLINE | ID: mdl-26579790

ABSTRACT

PURPOSE: To describe the outcomes of children with Coats disease treated with 577-nm yellow laser indirect ophthalmoscopy. METHODS: A retrospective consecutive case series of pediatric patients with Coats disease treated at a single institution between 2011 and 2014. Laser indirect ophthalmoscopy was performed under anesthesia. Full treatment was defined as complete ablation of all visible telangiectasias and resolution of subretinal fluid. No patients were treated with cryotherapy or bevacizumab. RESULTS: Seventeen eyes of 16 patients were consecutively treated. At the time of diagnosis, the eye was classified as Stage 1 (telangiectasias only) in 1 case, Stage 2A (extra-foveal exudation) in 2 cases, Stage 2B (fovea-involving exudation) in 6 cases, Stage 3A1 (extra-foveal exudative retinal detachment) in 2 cases, Stage 3A2 (subtotal foveal-involving detachment) in 1 case, and Stage 3B (total exudative retinal detachment) in 5 cases. The mean age at initial treatment was 71.2 months. Mean length of follow-up was 20.8 months (median 18.5 months, range 3.7-37.3 months). Patients underwent an average of 2.5 laser treatments. Sixteen of 17 eyes achieved full treatment (94.1%) with a mean time-to-full-treatment of 11.2 months. One eye developed glaucoma and end-stage disease. CONCLUSION: 577-nm yellow wavelength laser indirect ophthalmoscopy is an effective treatment for Coats disease including cases of exudative retinal detachment.


Subject(s)
Laser Coagulation , Retinal Telangiectasis/surgery , Adolescent , Child , Child, Preschool , Fluorescein Angiography , Follow-Up Studies , Humans , Infant , Male , Ophthalmoscopy , Retinal Detachment/diagnosis , Retinal Telangiectasis/classification , Retinal Telangiectasis/physiopathology , Retrospective Studies , Visual Acuity/physiology
14.
Am J Ophthalmol ; 160(3): 516-521.e2, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26032191

ABSTRACT

PURPOSE: To identify risk factors for device exposure and intraocular infection following implantation of a glaucoma drainage device. DESIGN: Retrospective case series. METHODS: The medical records of adult patients undergoing glaucoma drainage device implantation at an academic medical center between 2000 and 2010 were reviewed. Main outcome measures included device exposure and intraocular infection. RESULTS: Seven hundred and sixty-three cases were identified. These included 702 primary implants (ie, the first drainage device implanted into an eye) and 61 sequential implants. Among 702 primary implants, there were 41 cases of exposure (5.8%). None of the potential risk factors were statistically significant. Implant location was found to be a marginally significant risk factor. The exposure rates for inferior and superior implants were 12.8% (5 of 39) and 5.4% (36 of 663), respectively (P = .056). The highest rate of exposure for primary implants occurred in the inferior-nasal quadrant (17.2%, 5 of 29). The rate of exposure for sequential devices was 13.1% (8 of 61), with the highest rate also found in the inferior-nasal quadrant (20%, 5 of 25). Of 49 total exposures, 8 were associated with intraocular infection (16.3%). Exposures over inferior implants were more likely to be associated with infection than exposures over superior implants (41.7% vs 8.1%; P = .0151). CONCLUSION: Implant location approached, but did not reach, statistical significance as a risk factor for exposure. Exposures over inferior implants place patients at a higher risk of infection than superior exposures. More studies are needed to identify modifiable risk factors for device exposure.


Subject(s)
Endophthalmitis/epidemiology , Eye Infections, Bacterial/epidemiology , Glaucoma Drainage Implants , Pneumococcal Infections/epidemiology , Prosthesis Failure/adverse effects , Staphylococcal Infections/epidemiology , Surgical Wound Dehiscence/epidemiology , Aqueous Humor/microbiology , Endophthalmitis/microbiology , Eye Infections, Bacterial/microbiology , Female , Glaucoma/surgery , Humans , Intraocular Pressure , Male , Middle Aged , Pneumococcal Infections/microbiology , Retrospective Studies , Risk Factors , Staphylococcal Infections/microbiology , Staphylococcus/isolation & purification , Streptococcus pneumoniae/isolation & purification , Surgical Wound Dehiscence/microbiology
15.
J Biol Chem ; 286(1): 851-8, 2011 Jan 07.
Article in English | MEDLINE | ID: mdl-21056983

ABSTRACT

Cadherins and neuroligins (NLs) represent two families of cell adhesion proteins that are essential for the establishment of synaptic connections in vitro; however, it remains unclear whether these proteins act in concert to regulate synapse density. Using a combination of overexpression and knockdown analyses in primary hippocampal neurons, we demonstrate that NL1 and N-cadherin promote the formation of glutamatergic synapses through a common functional pathway. Analysis of the spatial relationship between N-cadherin and NL1 indicates that in 14-day in vitro cultures, almost half of glutamatergic synapses are associated with both proteins, whereas only a subset of these synapses are associated with N-cadherin or NL1 alone. This suggests that NL1 and N-cadherin are spatially distributed in a manner that enables cooperation at synapses. In young cultures, N-cadherin clustering and its association with synaptic markers precede the clustering of NL1. Overexpression of N-cadherin at this time point enhances NL1 clustering and increases synapse density. Although N-cadherin is not sufficient to enhance NL1 clustering and synapse density in more mature cultures, knockdown of N-cadherin at later time points significantly attenuates the density of NL1 clusters and synapses. N-cadherin overexpression can partially rescue synapse loss in NL1 knockdown cells, possibly due to the ability of N-cadherin to recruit NL2 to glutamatergic synapses in these cells. We demonstrate that cadherins and NLs can act in concert to regulate synapse formation.


Subject(s)
Cadherins/metabolism , Cell Adhesion Molecules, Neuronal/metabolism , Hippocampus/cytology , Synapses/metabolism , Animals , Cadherins/deficiency , Cadherins/genetics , Cell Adhesion Molecules, Neuronal/deficiency , Cell Adhesion Molecules, Neuronal/genetics , Cells, Cultured , Gene Knockdown Techniques , Glutamic Acid/metabolism , RNA, Small Interfering/genetics , Rats
16.
J Neurosci Res ; 88(4): 837-49, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19859968

ABSTRACT

Several recent studies have shown that neuroligin 2 (NL2), a component of the cell adhesion neurexins-neuroligins complex, is localized postsynaptically at hippocampal and other inhibitory synapses throughout the brain. Other studies have shown that components of the dystroglycan complex are also localized at a subset of inhibitory synapses and are coexpressed with NL2 in brain. These data prompted us to undertake a comparative study between the localization of NL2 and the dystroglycan complex in the rodent retina. First, we determined that NL2 mRNA is expressed both in the inner and in the outer nuclear layers. Second, we found that NL2 is localized both in the inner and in the outer synaptic plexiform layers. In the latter, the horseshoe-shaped pattern of NL2 and its extensive colocalization with RIM2, a component of the presynaptic active zone at ribbon synapses, argue that NL2 is localized presynaptically at photoreceptor terminals. Third, comparison of NL2 and the dystroglycan complex distribution patterns reveals that, despite their coexpression in the outer plexiform layer, they are spatially segregated within distinct domains of the photoreceptor terminals, where NL2 is selectively associated with the active zone and the dystroglycan complex is distally distributed in the lateral regions. Finally, we report that the dystroglycan deficiency in the mdx(3cv) mouse does not alter NL2 localization in the outer plexiform layer. These data show that the NL2- and dystroglycan-containing complexes are differentially localized in the presynaptic photoreceptor terminals and suggest that they may serve distinct functions in retina.


Subject(s)
Dystroglycans/metabolism , Membrane Proteins/metabolism , Nerve Tissue Proteins/metabolism , Retina/cytology , Synapses/metabolism , Animals , Cell Adhesion Molecules, Neuronal , Cells, Cultured , Cerebral Cortex/cytology , Disks Large Homolog 4 Protein , Dystroglycans/genetics , Embryo, Mammalian , Guanylate Kinases , Hippocampus/cytology , Intracellular Signaling Peptides and Proteins/metabolism , Membrane Proteins/genetics , Mice , Mice, Inbred mdx , Nerve Tissue Proteins/genetics , Neurons/metabolism , Rats , Rats, Sprague-Dawley , Synaptophysin/metabolism , Vesicular Glutamate Transport Protein 1/metabolism , Vesicular Inhibitory Amino Acid Transport Proteins/metabolism , rab3 GTP-Binding Proteins/metabolism
17.
J Vet Emerg Crit Care (San Antonio) ; 19(5): 496-500, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19821893

ABSTRACT

OBJECTIVE: To compare the histopathologic diagnosis in dogs with spontaneous hemoperitoneum when abdominal ultrasonographic examination detects a solitary versus multiple lesions. DESIGN: Retrospective cross-sectional study. SETTING: Private veterinary hospital. ANIMALS: Client-owned dogs presented with spontaneous hemoperitoneum between March 1, 2003 and June 1, 2008. INTERVENTIONS: Dogs were divided into 2 groups based on presence of a solitary or multiple abdominal ultrasonographic lesions. Prevalences were compared between groups for malignancy and specifically hemangiosarcoma. MEASUREMENTS AND MAIN RESULTS: Ten of 31 (32%) dogs had a solitary abdominal ultrasonographic lesion and 21 of 31 (68%) had more than 1 lesion. The bleeding tissue was characterized as malignant in 8 of 10 (80%) dogs with solitary lesions and 17 of 21 (81%) dogs with multiple lesions; there was no significant difference (P=1.0) between groups. In this study no association (P=0.26) was found between the number of abdominal ultrasonographic lesions observed and subsequent diagnosis of hemangiosarcoma. CONCLUSIONS: Solitary abdominal ultrasonographic lesions in dogs with spontaneous hemoperitoneum do not necessarily indicate a lower prevalence of malignancy.


Subject(s)
Abdominal Neoplasms/veterinary , Dog Diseases/diagnosis , Hemoperitoneum/veterinary , Abdominal Neoplasms/diagnosis , Abdominal Neoplasms/diagnostic imaging , Animals , Cross-Sectional Studies , Dog Diseases/diagnostic imaging , Dogs , Female , Male , Retrospective Studies , Risk Factors , Ultrasonography
18.
J Biol Chem ; 283(47): 32944-56, 2008 Nov 21.
Article in English | MEDLINE | ID: mdl-18819924

ABSTRACT

Perturbations in neuregulin-1 (NRG1)/ErbB4 function have been associated with schizophrenia. Affected patients exhibit altered levels of these proteins and display hypofunction of glutamatergic synapses as well as altered neuronal circuitry. However, the role of NRG1/ErbB4 in regulating synapse maturation and neuronal process formation has not been extensively examined. Here we demonstrate that ErbB4 is expressed in inhibitory interneurons at both excitatory and inhibitory postsynaptic sites. Overexpression of ErbB4 postsynaptically enhances size but not number of presynaptic inputs. Conversely, knockdown of ErbB4 using shRNA decreases the size of presynaptic inputs, demonstrating a specific role for endogenous ErbB4 in synapse maturation. Using ErbB4 mutant constructs, we demonstrate that ErbB4-mediated synapse maturation requires its extracellular domain, whereas its tyrosine kinase activity is dispensable for this process. We also demonstrate that depletion of ErbB4 decreases the number of primary neurites and that stimulation of ErbB4 using a soluble form of NRG1 results in exuberant dendritic arborization through activation of the tyrosine kinase domain of ErbB4 and the phosphoinositide 3-kinase pathway. These findings demonstrate that NRG1/ErbB4 signaling differentially regulates synapse maturation and dendritic morphology via two distinct mechanisms involving trans-synaptic signaling and tyrosine kinase activity, respectively.


Subject(s)
ErbB Receptors/metabolism , Neuregulins/metabolism , Signal Transduction , Animals , COS Cells , Chlorocebus aethiops , Dendrites/metabolism , Hippocampus/metabolism , Humans , Mice , Models, Biological , Neurons/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Rats , Receptor, ErbB-4 , Synapses/metabolism
19.
Mol Biol Cell ; 19(5): 2026-38, 2008 May.
Article in English | MEDLINE | ID: mdl-18287537

ABSTRACT

Dendritic filopodia are thought to participate in neuronal contact formation and development of dendritic spines; however, molecules that regulate filopodia extension and their maturation to spines remain largely unknown. Here we identify paralemmin-1 as a regulator of filopodia induction and spine maturation. Paralemmin-1 localizes to dendritic membranes, and its ability to induce filopodia and recruit synaptic elements to contact sites requires protein acylation. Effects of paralemmin-1 on synapse maturation are modulated by alternative splicing that regulates spine formation and recruitment of AMPA-type glutamate receptors. Paralemmin-1 enrichment at the plasma membrane is subject to rapid changes in neuronal excitability, and this process controls neuronal activity-driven effects on protrusion expansion. Knockdown of paralemmin-1 in developing neurons reduces the number of filopodia and spines formed and diminishes the effects of Shank1b on the transformation of existing filopodia into spines. Our study identifies a key role for paralemmin-1 in spine maturation through modulation of filopodia induction.


Subject(s)
Dendritic Spines/metabolism , Membrane Proteins/metabolism , Phosphoproteins/metabolism , Pseudopodia/metabolism , Alternative Splicing/genetics , Animals , COS Cells , Cell Membrane/metabolism , Chlorocebus aethiops , Lipoylation , Mice , Protein Transport , Rats , Receptors, AMPA/metabolism , Time Factors
20.
Neuron ; 56(6): 937-9, 2007 Dec 20.
Article in English | MEDLINE | ID: mdl-18093514

ABSTRACT

Neuronal circuits are maintained by homeostatic mechanisms controlling synapse maturation and signaling. Neuroligins (NLs) and neurexins (Nrxs) may regulate the fine balance between excitation and inhibition. In this issue of Neuron, Araç et al. and Fabrichny et al. define crystal structures of NLs bound to beta-Nrx, providing insights into their synaptic actions and clarifying structural defects associated with autism-linked mutations.


Subject(s)
Membrane Proteins/physiology , Neural Cell Adhesion Molecules/physiology , Synapses/metabolism , Animals , Humans , Membrane Proteins/chemistry , Mutation/physiology , Neural Cell Adhesion Molecules/chemistry , Protein Binding
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