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2015
The authors describe a 20-year-old man who sustained multiple facial fractures in a high-speed motor vehicle crash, including a bone fragment from a skull base fracture that penetrated the orbital soft tissues superomedially. Serial CT scans documented spontaneous resorption over a 6-month period. While it is known that autologous bone grafts used in craniofacial reconstruction exhibit variable amounts of bone resorption, the complete resorption of an intraorbital fracture fragment has not been documented in the literature. His clinical care and the report of his case were undertaken in a fashion in accordance with the principles of the Health Insurance Portability and Accountability Act regulations.
Mucormycosis is a rare often fatal opportunistic fungal infection. It is typically described in patients with diabetes in ketoacidotic status and is rare in renal transplant recipients. Calciphylaxis is a rare and highly morbid disease of vascular calcification affecting patients with end-stage renal disease (ESRD). The first case of a renal transplant recipient who was inflicted with both rhinoorbitocerebral mucormycosis and calciphylaxis is reported. A 45-year-old man presented with 2-day history of left upper blepharoptosis, periorbital pain, left-sided headache, binocular diplopia, and left V2 numbness. He had undergone renal transplant for ESRD 7 months earlier with resultant immunosuppressive therapy. MRI and nasal biopsy confirmed rhinoorbitocerebral mucormycosis. Immunosuppressive therapy was stopped and antifungal therapy begun. He had orbital exenteration for progressive rhinoorbitocerebral mucormycosis. Two months later, the patient reported new-onset intermittent bitemporal headache and bilateral swollen, tender temporal arteries. Temporal artery biopsy revealed features consistent with calciphylaxis. Clinical presentation, treatment course, and follow up are discussed.
Neuroendocrine malignancies-tumors characterized by the production of dense-core secretory granules-are most often encountered in the lungs and can also be found in extrapulmonary sites. Our patient had a primary neuroendocrine tumor of the antrum with an elusive cell of origin that secondarily invaded the inferior orbit. In the sinuses, neuroendocrine tumors may be confused with infectious sinusitis or squamous cell carcinoma. There are no known pathognomonic clinical or radiographic signs to distinguish these tumors from other conditions. Diagnosis depends on a biopsy with histopathologic and immunohistochemical analysis to identify biomarkers such as synaptophysin, chromogranin, CD56 and neuron specific enolase. Our patient's tumor defied precise immunohistochemical characterization because of its primitive character and erratic biomarker expression. The diagnosis oscillated between a neuroendocrine carcinoma and an ectopic esthesioneuroblastoma grade IV-hence the use of the more generic nosologic category of neuroendocrine neoplasm without specifying a neuronal or epithelial origin. Data to guide management are limited, particularly in the ophthalmic literature, and derive from experience with tumors of the sinonasal compartments. In the present case of a sino-orbital high grade neuroendocrine neoplasm, regional lymph node metastases developed shortly after presentation. The tumor has responded well to chemotherapy and radiation, but recurrence is often encountered within 2 years in this class of neoplasms.
IMPORTANCE: Asymmetric horizontal strabismus surgery is often performed to correct primary gaze alignment without considering the symptoms that may result from misalignment in the patient's side gaze. Surgical choices influence alignment in side gaze and may contribute to functional and social deficits. OBJECTIVE: To identify the surgical procedures associated with changes of alignment in side gaze to help inform surgical planning for patients with horizontal strabismus. DESIGN, SETTING, AND PARTICIPANTS: The medical records of 1081 horizontal strabismus surgical procedures that were performed at Boston Children's Hospital during a 2-year period were retrospectively reviewed. Only records with strabismus measurements recorded in the right and left gaze before and after surgery were included. Data analysis was conducted from September 1, 2012, through June 7, 2015. MAIN OUTCOMES AND MEASURES: Change in comitance (CIC), determined by measuring the horizontal comitance (the difference between right- and left-gaze strabismus measurements) before and after surgery. RESULTS: The review identified 569 patients who met the inclusion criteria. Of the 491 patients with comitant preoperative alignment, 59 developed postoperative incomitance, of whom 53 (89.9%) had asymmetric surgery. Of the 78 patients with incomitant preoperative alignment, 36 patients' (46.2%) deviation had improved to comitance after surgery; 32 (88.9%) of these patients had asymmetric surgery. Asymmetric 2-muscle surgery had a median CIC of 4.0 while symmetric 2-muscle surgery had a median CIC of 1.5 (difference in CIC, 2.5; 95% CI, 2.0-3.0; P < .001). A CIC of 25 prism diopters or more was observed in 6 patients who underwent asymmetric surgery (0 with symmetric surgery). New postoperative incomitance was symptomatic in at least 17 patients (28.8%). CONCLUSIONS AND RELEVANCE: Asymmetric strabismus surgery can treat incomitant deviations, but it can also create symptomatic incomitant deviations in patients who were previously comitant. Surgical planning should include consideration of the potential for CIC, including the potential for unsatisfactory appearance in side gaze. Patients with binocular vision will be sensitive to diplopia in any gaze direction; in such cases, the consequences of asymmetric surgery should be considered with particular care.
The cornea is the shield to the foreign world and thus, a primary site for peripheral infections. However, transparency and vision are incompatible with inflammation and scarring that may result from infections. Thus, the cornea is required to perform a delicate balance between fighting infections and preserving vision. To date, little is known about the specific role of antigen-presenting cells in viral keratitis. In this study, utilizing an established murine model of primary acute herpes simplex virus (HSV)-1 keratitis, we demonstrate that primary HSV keratitis results in increased conventional dendritic cells (cDCs) and macrophages within 24 hours after infection. Local depletion of cDCs in CD11c-DTR mice by subconjuntival diphtheria toxin injections, led to increased viral proliferation, and influx of inflammatory cells, resulting in increased scarring and clinical keratitis. In addition, while HSV infection resulted in significant corneal nerve destruction, local depletion of cDCs resulted in a much more severe loss of corneal nerves. Further, local cDC depletion resulted in decreased corneal nerve infection, and subsequently decreased and delayed systemic viral transmission in the trigeminal ganglion and draining lymph node, resulting in decreased mortality of mice. In contrast, sham depletion or depletion of macrophages through local injection of clodronate liposomes had neither a significant impact on the cornea, nor an effect on systemic viral transmission. In conclusion, we demonstrate that corneal cDCs may play a primary role in local corneal defense during viral keratitis and preserve vision, at the cost of inducing systemic viral dissemination, leading to increased mortality.
The medial ganglionic eminence (MGE) gives rise to the majority of mouse forebrain interneurons. Here, we examine the lineage relationship among MGE-derived interneurons using a replication-defective retroviral library containing a highly diverse set of DNA barcodes. Recovering the barcodes from the mature progeny of infected progenitor cells enabled us to unambiguously determine their respective lineal relationship. We found that clonal dispersion occurs across large areas of the brain and is not restricted by anatomical divisions. As such, sibling interneurons can populate the cortex, hippocampus striatum, and globus pallidus. The majority of interneurons appeared to be generated from asymmetric divisions of MGE progenitor cells, followed by symmetric divisions within the subventricular zone. Altogether, our findings uncover that lineage relationships do not appear to determine interneuron allocation to particular regions. As such, it is likely that clonally related interneurons have considerable flexibility as to the particular forebrain circuits to which they can contribute.
The mammalian neocortex is composed of two major neuronal cell types with distinct origins: excitatory pyramidal neurons and inhibitory interneurons, generated in dorsal and ventral progenitor zones of the embryonic telencephalon, respectively. Thus, inhibitory neurons migrate relatively long distances to reach their destination in the developing forebrain. The role of lineage in the organization and circuitry of interneurons is still not well understood. Utilizing a combination of genetics, retroviral fate mapping, and lineage-specific retroviral barcode labeling, we find that clonally related interneurons can be widely dispersed while unrelated interneurons can be closely clustered. These data suggest that migratory mechanisms related to the clustering of interneurons occur largely independent of their clonal origin.
Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in the elderly of industrialized nations, and there is increasing evidence to support a role for chronic inflammation in its pathogenesis. Mitochondrial DNA (mtDNA) has been recently reported to be pro-inflammatory in various diseases such as Alzheimer's and heart failure. Here, we report that intracellular mtDNA induces ARPE-19 cells to secrete inflammatory cytokines IL-6 and IL-8, which have been consistently associated with AMD onset and progression. The induction was dependent on the size of mtDNA, but not on specific sequence. Oxidative stress plays a major role in the development of AMD, and our findings indicate that mtDNA induces IL-6 and IL-8 more potently when oxidized. Cytokine induction was mediated by STING (Stimulator of Interferon Genes) and NF-κB as evidenced by abrogation of the cytokine response with the use of specific inhibitors (siRNA and BAY 11-7082, respectively). Finally, mtDNA primed the NLRP3 inflammasome. This study contributes to our understanding of the potential pro-inflammatory role of mtDNA in the pathogenesis of AMD.
PURPOSE: To evaluate whether the densities of corneal subbasal nerves and epithelial immune dendritiform cells (DCs) are comparable between a set of three representative standard images of in vivo confocal microscopy (IVCM) and the wide-field mapped composite IVCM images. METHODS: This prospective, cross-sectional, and masked study included 110 eyes of 58 patients seen in a neurology clinic who underwent laser-scanning IVCM (Heidelberg Retina Tomograph 3) of the central cornea. Densities of subbasal corneal nerves and DCs were compared between the average of three representative standard images and the wide-field mapped composite images, which were reconstructed by automated mapping. RESULTS: There were no statistically significant differences between the average of three representative standard images (0.16 mm2 each) and the wide-field composite images (1.29 ± 0.64 mm2) in terms of mean subbasal nerve density (17.10 ± 6.10 vs. 17.17 ± 5.60 mm/mm2, respectively, P = 0.87) and mean subbasal DC density (53.2 ± 67.8 vs. 49.0 ± 54.3 cells/mm2, respectively, P = 0.43). However, there were notable differences in subbasal nerve and DC densities between these two methods in eyes with very low nerve density or very high DC density. CONCLUSIONS: There are no significant differences in the mean subbasal nerve and DC densities between the average values of three representative standard IVCM images and wide-field mapped composite images. Therefore, these standard images can be used in clinical studies to accurately measure cellular structures in the subbasal layer.
Corneal epithelial basement membrane dystrophies and superficial injuries caused by scratches can lead to recurrent corneal erosion syndrome (RCES). Patients and animals with reduced corneal sensory nerve innervation can also develop recurrent erosions. Multiple wild-type mouse strains will spontaneously develop recurrent corneal erosions after single 1.5 mm debridement wounds. Here we show that this wound is accompanied by an increase in corneal epithelial cell proliferation after wound closure but without a commensurate increase in corneal epithelial thickness. We investigated whether excess corneal epithelial cell proliferation contributes to erosion formation. We found that topical application of Mitomycin C (MMC), a drug used clinically to improve healing after glaucoma and refractive surgery, reduces erosion frequency, enhances subbasal axon density to levels seen in unwounded corneas, and prevents excess epithelial cell proliferation after debridement wounding. These results suggest that topically applied MMC, which successfully reduces corneal haze and scarring after PRK, may also function to enhance subbasal nerve regeneration and epithelial adhesion when used to treat RCES.
Vesicular stomatitis virus has been shown to bud basolaterally, and the matrix protein, but not glycoprotein, was proposed to mediate this asymmetry. Using polarized T84 monolayers, we demonstrate that no single viral protein is sufficient for polarized budding. Particles are released from the apical and basolateral surfaces and are indistinguishable, indicating that there is no apical assembly defect. We propose that aspects of host cell polarity create a more efficient budding process at the basolateral surface.
Viruses within human adenovirus species D (HAdV-D) infect epithelia at essentially every mucosal site. Hypervariable loops 1 and 2 of the hexon capsid protein contain epitopes that together form the epsilon determinant for serum neutralization. We report our analyses comparing HAdV-D15, 29, 56, and the recently identified type 69, each with highly similar hexons and the same serum neutralization profile, but otherwise disparate genomes. Of these, only HAdV-D type 56 is associated with epidemic keratoconjunctivitis (EKC), a severe infection of ocular surface epithelium and underlying corneal stroma. In the mouse adenovirus keratitis model, all four viruses induced inflammation. However, HAdV-D56 entry into human corneal epithelial cells and fibroblasts in vitro dramatically exceeded that of the other three viruses. We conclude that the hexon epsilon determinant is not a prime contributor to corneal tropism.
The X-linked RP3 gene codes for the ciliary protein RPGR and accounts for over 10% of inherited retinal degenerations. The critical RPGR-ORF15 splice variant contains a highly repetitive purine-rich linker region that renders it unstable and difficult to adapt for gene therapy. To test the hypothesis that the precise length of the linker region is not critical for function, we evaluated whether adeno-associated virus-mediated replacement gene therapy with a human ORF15 variant containing in-frame shortening of the linker region could reconstitute RPGR function in vivo. We delivered human RPGR-ORF15 replacement genes with deletion of most (314 codons, 'short form') or 1/3 (126 codons, 'long form') of the linker region to Rpgr null mice. Human RPGR-ORF15 expression was detected post treatment with both forms of ORF15 transgenes. However, only the long form correctly localized to the connecting cilia and led to significant functional and morphological rescue of rods and cones. Thus the highly repetitive region of RPGR is functionally important but that moderate shortening of its length, which confers the advantage of added stability, preserves its function. These findings provide a theoretical basis for optimizing replacement gene design in clinical trials for X-linked RP3.
PURPOSE: To assess whether the presence of peripheral nonperfusion on ultrawide field (UWF) fluorescein angiography (FA) is associated with diabetic retinopathy (DR) severity and the presence of predominantly peripheral lesions (PPLs). DESIGN: Single-site, cross-sectional, retrospective study. PARTICIPANTS: Sixty-eight eyes of 37 diabetic subjects with or without DR and no history of prior panretinal laser photocoagulation. METHODS: Both 200° UWF images and UWF FA images were acquired at the same visit. Early Treatment Diabetic Retinopathy Study (ETDRS) templates were overlaid digitally based on disc and macula location onto stereographically projected UWF images. Images were evaluated for the presence of PPLs, defined as more than 50% of the graded lesion located outside the ETDRS field in each of the 5 extended fields. The UWF-FA images were evaluated by 2 masked, independent graders for extent of retinal nonperfusion area (NPA) and nonperfusion index (NPI; nonperfused/total gradable area). MAIN OUTCOME MEASURES: Association of NPA and NPI with DR severity and presence of PPLs. RESULTS: Distribution of DR severity was as follows: no DR, 8.8% eyes; mild nonproliferative DR (NPDR), 17.6%; moderate NPDR, 32.4%; severe NPDR, 17.6%; proliferative DR (PDR), 19.1%; and high-risk PDR, 4.4%; with PPL present in 61.8%. There was strong intragrader (r = 0.95) and intergrader (r = 0.86) agreement for NPA. Presence of PPLs was associated with increased NPA (191.8 mm(2) vs. 306.1 mm(2); P = 0.0019) and NPI (0.25 vs. 0.43; P = 0.0003). These relationships remained significant after adjusting for DR severity and diabetes duration. In eyes without PDR (n = 52), increasing NPA and NPI was associated with worsening DR (NPA, P = 0.001; NPI, P = 0.0003). NPA and NPI were not associated with clinically significant macular edema (NPA, P = 0.99; NPI, P = 0.67), nor correlated with visual acuity (NPA, r = 0.14, P = 0.23; NPI, r = 0.24, P = 0.05). CONCLUSIONS: Following a standardized protocol, the evaluation of UWF FA for NPA and NPI is reproducible. Both parameters are correlated highly with the presence of PPLs and DR severity. Given that the presence and extent of PPLs have been associated with increased risks of DR progression, the clinical identification of PPLs may reflect closely the extent of nonperfusion and ischemia, thus accounting for the increased risk of progression.
Autism spectrum disorders (ASDs) are a range of complex neurodevelopmental conditions principally characterized by dysfunctions linked to mental development. Previous studies have shown that there are more than 1000 genes likely involved in ASD, expressed mainly in brain and highly interconnected among them. We applied whole exome sequencing in Colombian-South American trios. Two missense novel SNVs were found in the same child: ALDH1A3 (RefSeq NM_000693: c.1514T>C (p.I505T)) and FOXN1 (RefSeq NM_003593: c.146C>T (p.S49L)). Gene expression studies reveal that Aldh1a3 and Foxn1 are expressed in ~E13.5 mouse embryonic brain, as well as in adult piriform cortex (PC; ~P30). Conserved Retinoic Acid Response Elements (RAREs) upstream of human ALDH1A3 and FOXN1 and in mouse Aldh1a3 and Foxn1 genes were revealed using bioinformatic approximation. Chromatin immunoprecipitation (ChIP) assay using Retinoid Acid Receptor B (Rarb) as the immunoprecipitation target suggests RA regulation of Aldh1a3 and Foxn1 in mice. Our results frame a possible link of RA regulation in brain to ASD etiology, and a feasible non-additive effect of two apparently unrelated variants in ALDH1A3 and FOXN1 recognizing that every result given by next generation sequencing should be cautiously analyzed, as it might be an incidental finding.
Pathologic ocular angiogenesis is a leading cause of blindness, influenced by both dysregulated lipid metabolism and inflammation. Retinoic-acid-receptor-related orphan receptor alpha (RORα) is a lipid-sensing nuclear receptor with diverse biologic function including regulation of lipid metabolism and inflammation; however, its role in pathologic retinal angiogenesis remains poorly understood. Using a mouse model of oxygen-induced proliferative retinopathy, we showed that RORα expression was significantly increased and genetic deficiency of RORα substantially suppressed pathologic retinal neovascularization. Loss of RORα led to decreased levels of proinflammatory cytokines and increased levels of antiinflammatory cytokines in retinopathy. RORα directly suppressed the gene transcription of suppressors of cytokine signaling 3 (SOCS3), a critical negative regulator of inflammation. Inhibition of SOCS3 abolished the antiinflammatory and vasoprotective effects of RORα deficiency in vitro and in vivo. Moreover, treatment with a RORα inverse agonist SR1001 effectively protected against pathologic neovascularization in both oxygen-induced retinopathy and another angiogenic model of very-low-density lipoprotein receptor (Vldlr)-deficient (Vldlr (-/-) ) mice with spontaneous subretinal neovascularization, whereas a RORα agonist worsened oxygen-induced retinopathy. Our data demonstrate that RORα is a novel regulator of pathologic retinal neovascularization, and RORα inhibition may represent a new way to treat ocular neovascularization.
Exfoliation syndrome (XFS) is an important risk factor for glaucoma (XFG) worldwide. LOXL1 variants are highly associated with XFS in most populations; however, the high frequency of risk alleles in normal individuals and the reversal of risk alleles in different ethnic populations suggest that other factors contribute to XFS pathogenesis. Clusterin (CLU) is an extracellular matrix chaperone that prevents protein aggregation and is highly expressed in ocular tissues affected by XFS. Studies examining common CLU variants for association with XFS have been inconsistent. The purpose of this study was to evaluate CLU variants for association with XFS in two independent datasets from the United States (222 cases and 344 controls) and Israel (92 cases and 102 controls). Seven tag SNPs that captured >95% of alleles at r(2) greater than 0.8 across the CLU genomic region were genotyped using TaqMan assays. Genotypes for an additional SNP, rs2279590, were imputed using phased haplotypes of HapMap reference CEU samples. Of the 8 CLU SNPs selected for the study, none were significantly associated with XFS in either case-control group (age and sex adjusted P > 0.14 and 0.36, respectively, in the US and Israeli datasets), or when they were meta-analyzed together (age and sex adjusted P > 0.13). Haplotype analysis using all 8 SNPs or only the promoter region SNPs also did not show significant associations of CLU with XFS in the combined US and Israeli dataset (P > 0.28). Meta-analysis of the data from this study and previous studies in Caucasian populations (1184 cases and 978 controls) resulted in statistically significant association of rs2279590 with XFS (summary OR = 1.18, 95% CI: 1.03-1.33, P = 0.01). Significant association between rs2279590 and XFS was also found in Indian populations (summary OR = 0.76, 95% CI: 0.61-0.96; P = 0.02); however, significant heterogeneity between the Caucasian and Indian populations possibly due to reversal of the risk allele precluded an overall meta-analysis for rs2279590 (Q = 0.001, I(2) = 91%). No significant association was identified for rs3087554 in either Caucasian populations (summary OR = 0.90, 95% CI: 0.77-1.05, P = 0.17) or Indian populations (summary OR = 0.89, 95% CI: 0.72-1.10, P = 0.28), or in both populations combined (1705 cases and 3713 controls; summary OR = 0.90, 95% CI: 0.79-1.01, P = 0.08). Significant heterogeneity precluded the addition of the Japanese data to the meta-analysis for rs3087554 (Q = 0.006, I(2) = 87%). Our results suggest that common CLU variants may contribute to modest XFS risk but even larger datasets are required to confirm these findings.
There are many transgenic GFP reporter lines that allow the visualization of specific populations of cells. Using such lines for functional studies requires a method that transforms GFP into a molecule that enables genetic manipulation. We developed a method that exploits GFP for gene manipulation, Cre recombinase dependent on GFP (CRE-DOG), a split component system that uses GFP and its derivatives to directly induce Cre/loxP recombination. Using plasmid electroporation and AAV viral vectors, we delivered CRE-DOG to multiple GFP mouse lines, which led to effective recombination selectively in GFP-labeled cells. Furthermore, CRE-DOG enabled optogenetic control of these neurons. Beyond providing a new set of tools for manipulation of gene expression selectively in GFP(+) cells, we found that GFP can be used to reconstitute the activity of a protein not known to have a modular structure, suggesting that this strategy might be applicable to a wide range of proteins.
PURPOSE: To investigate the longitudinal alterations of subbasal corneal nerves in patients with infectious keratitis (IK) during the acute phase, cessation of treatment, and the recovery phase by in vivo confocal microscopy (IVCM). DESIGN: Prospective, longitudinal, case-control, single-center study. PARTICIPANTS: Fifty-six eyes of 56 patients with the diagnosis of bacterial (n = 28), fungal (n = 15), or Acanthamoeba (n = 13) keratitis were included in the study. Thirty eyes of 30 normal volunteers constituted the control group. METHODS: Corneal sensation and serial IVCM of the central cornea were performed prospectively using the Heidelberg Retina Tomograph 3/Rostock Cornea Module (Heidelberg Engineering, Heidelberg, Germany). The IVCM images were assessed at 3 time points: at the acute phase (first visit to the cornea service), at cessation of antimicrobial treatment, and up to 6 months after the resolution of infection. MAIN OUTCOME MEASURES: Total nerve number and length, main nerve trunks, branching, and corneal sensation were assessed during the follow-up period. RESULTS: Corneal nerves were reduced significantly during the acute phase in eyes with IK compared with controls across all subgroups, with total nerve length of 5.47±0.69 mm/mm(2) versus 20.59±1.06 mm/mm(2) (P <0.0001). At the cessation of treatment, corneal nerves in patients with IK had regenerated, including total nerve length (8.49±0.94 mm/mm(2); P = 0.02) and nerve branch length (4.80±0.37 mm/mm(2); P = 0.005). During the recovery phase, after resolution of infection, corneal nerves regenerated further, including total nerve length (12.13±1.97 mm/mm(2); P = 0.005), main nerve trunk length (5.80±1.00 mm/mm(2); P = 0.01), and nerve branch length (6.33±0.76 mm/mm(2); P = 0.003) as compared with the acute phase, but were still significantly lower when compared with controls (P < 0.05 for all parameters). Corneal degeneration and regeneration correlated with corneal sensation (r = 0.47; P = 0.0009). CONCLUSIONS: Patients with IK who sustain profound loss of corneal nerves during the acute phase of infection demonstrate increased corneal nerve density during the first 6 months after the resolution of infection. However, despite significant nerve regeneration, corneal nerve density does not recover fully and remains low compared to controls. By providing an objective methodology to monitor corneal re-innervation, IVCM adds potentially important findings that may have implications for clinical management and surgical planning.
IMPORTANCE: The sensitivity of acetylcholine receptor (AChR) antibody testing is thought to be lower in ocular myasthenia gravis (OMG) compared with generalized disease, although estimates in small-scale studies vary. There is little information in the literature about the implications of AChR antibody levels and progression from OMG to generalized myasthenia gravis. OBJECTIVES: To test the hypothesis that serum AChR antibody testing is more sensitive in OMG than previously reported and to examine the association between AChR antibody levels and progression from OMG to generalized myasthenia gravis. DESIGN, SETTING, AND PARTICIPANTS: A retrospective, observational cohort study was conducted of 223 patients (mean [SD] age, 59.2 [16.4] years; 139 [62.3%] male) diagnosed with OMG between July 1, 1986, and May 31, 2013, at 2 large, academic medical centers. MAIN OUTCOMES AND MEASURES: Baseline characteristics, OMG symptoms, results of AChR antibody testing, and progression time to generalized myasthenia gravis (if this occurred) were recorded for each patient. Multiple logistic regression was used to measure the association between all clinical variables and antibody result. Kaplan-Meier survival analysis was performed to examine time to generalization. RESULTS: Among the 223 participants, AChR antibody testing results were positive in 158 participants (70.9%). In an adjusted model, increased age at diagnosis (odds ratio [OR], 1.03; 95% CI, 1.01-1.04; P = .007) and progression to generalized myasthenia gravis (OR, 2.92; 95% CI, 1.18-7.26; P = .02) were significantly associated with positive antibody test results. Women were less likely to have a positive antibody test result (OR, 0.36; 95% CI, 0.19-0.68; P = .002). Patients who developed symptoms of generalized myasthenia gravis had a significantly higher mean (SD) antibody level than those who did not develop symptoms of generalized myasthenia gravis (12.7 [16.5] nmol/L vs 4.2 [7.9] nmol/L; P = .002). CONCLUSIONS AND RELEVANCE: We demonstrate a higher sensitivity of AChR antibody testing than previously reported in the largest cohort of patients with OMG available to date. Older age, male sex, and progression to generalized myasthenia gravis were significantly associated with a positive antibody test result. In addition, to our knowledge, this is the first report of an association between high AChR antibody levels and progression from OMG to generalized disease.
UNLABELLED: Oral delivery of poorly soluble and permeable drugs represents a significant challenge in drug development. The oral delivery of drugs remains to be the ultimate route of any drugs. However, in many cases, drugs are not absorbed well in the gastrointestinal tract, or they lose their activity. Polymer micelles were recognized as an effective carrier system for drug encapsulation, and are now studied as a vehicle for oral delivery of insoluble compounds. We characterized the properties of monomethoxy polyethylene glycol-poly lactic acid (mPEG-PLA) micelles, and visualized their internalization in mouse small intestine. Using Caco-2 cells as a cellular model, we studied the kinetics of particle uptake, their transport, and the molecular mechanism of their intestinal absorption. Moreover, by inhibiting specific endocytosis pathways, pharmacologically and genetically, we found that mPEG-PLA nanoparticle endocytosis is mediated by clathrin in an energy-dependent manner, and that the low-density lipoprotein receptor is involved. FROM THE CLINICAL EDITOR: Many current drugs used are non-water soluble and indeed, the ability to deliver these drugs via the gastrointestinal tract remains the holy grail for many researchers. The authors in this paper developed monomethoxy polyethylene glycol-poly lactic acid (mPEG-PLA) micelles as a drug nanocarrier, and studied the mechanism of uptake across intestinal cells. The findings should improve our current understanding and point to the development of more nanocarriers.
