Incidence of Postsurgical Intraocular Inflammation 6 Months After Implantation with a Multifocal Intraocular Lens.

Purpose: This study assessed the incidence of postsurgical intraocular inflammation after cataract extraction by phacoemulsification and implantation with AcrySof IQ ReSTOR intraocular lenses (IOLs) produced using an updated manufacturing process. Incidence rates were compared with historical rates of postsurgical intraocular inflammation. Methods: This was a prospective, multicenter, post-approval study at 34 sites. Patients aged ≥22 years received a study lens in at least 1 eye. Postsurgical intraocular inflammation (aqueous cell grade ≥3+ within 14 days after surgery, aqueous cell ≥2+ at 14 to ≤60 days after surgery, or aqueous cell ≥1+ at >60 days) was assessed within a 180-day period after implantation. Rates of toxic anterior segment syndrome (TASS), acute postoperative endophthalmitis, chronic postoperative endophthalmitis, and uncategorized cases of postsurgical intraocular inflammation were assessed. Ocular adverse events (AEs) and ocular adverse device effects (ADEs) were evaluated. Historical rates of postsurgical intraocular inflammation were determined from the 2011-2013 Medicare Limited Data Set files (a 5% sample of the Medicare data set representative of patients aged ≥65 years). Results: Final safety analysis set included 3357 eyes (1792 patients; mean age, 68.6 ± 7.9 years). Postsurgical intraocular inflammation (any type) rate was 5.1 per 1000 attempted IOL implants (95% CI, 2.95, 8.10). TASS, acute postoperative endophthalmitis, and uncategorized inflammation rates were 0.6 (95% CI, 0.07, 2.15), 0.3 (95% CI, 0.01, 1.66), and 4.2 (95% CI, 2.28, 6.99) per 1000 attempted IOL implants, respectively. There were no events of chronic postoperative endophthalmitis. Ocular AEs and ADEs were reported in 17% and 1.5% of eyes, respectively. Most common ADEs were halo (0.63%) and glare (0.51%). The historical postsurgical inflammation rate from 221,519 cataract procedures was 10.3/1000 cataract surgeries, and the endophthalmitis rate was 1.2/1000 surgeries. Conclusion: The updated IOL manufacturing process resulted in postoperative intraocular inflammation rates that were substantially lower than the historic rate.

Minimally Invasive Treatment Options for Hepatic Uveal Melanoma Metastases.

Uveal melanoma is one of the most common primary intraocular malignancies that accounts for about 85% of all ocular melanomas. The pathophysiology of uveal melanoma is distinct from cutaneous melanoma and has separate tumor profiles. The management of uveal melanoma is largely dependent on the presence of metastases, which confers a poor prognosis with a one-year survival reaching only 15%. Although a better understanding of tumor biology has led to the development of novel pharmacologic agents, there is increasing demand for minimally invasive management of hepatic uveal melanoma metastases. Multiple studies have already summarized the systemic therapeutic options available for metastatic uveal melanoma. This review covers the current research for the most prevalent locoregional treatment options for metastatic uveal melanoma including percutaneous hepatic perfusion, immunoembolization, chemoembolization, thermal ablation, and radioembolization.

The C-terminal tail of polycystin-1 suppresses cystic disease in a mitochondrial enzyme-dependent fashion.

Autosomal dominant polycystic kidney disease (ADPKD) is the most prevalent potentially lethal monogenic disorder. Mutations in the PKD1 gene, which encodes polycystin-1 (PC1), account for approximately 78% of cases. PC1 is a large 462-kDa protein that undergoes cleavage in its N and C-terminal domains. C-terminal cleavage produces fragments that translocate to mitochondria. We show that transgenic expression of a protein corresponding to the final 200 amino acid (aa) residues of PC1 in two Pkd1-KO orthologous murine models of ADPKD suppresses cystic phenotype and preserves renal function. This suppression depends upon an interaction between the C-terminal tail of PC1 and the mitochondrial enzyme Nicotinamide Nucleotide Transhydrogenase (NNT). This interaction modulates tubular/cyst cell proliferation, the metabolic profile, mitochondrial function, and the redox state. Together, these results suggest that a short fragment of PC1 is sufficient to suppress cystic phenotype and open the door to the exploration of gene therapy strategies for ADPKD.

Membrane potential drives the exit from pluripotency and cell fate commitment via calcium and mTOR.

Transitioning from pluripotency to differentiated cell fates is fundamental to both embryonic development and adult tissue homeostasis. Improving our understanding of this transition would facilitate our ability to manipulate pluripotent cells into tissues for therapeutic use. Here, we show that membrane voltage (Vm) regulates the exit from pluripotency and the onset of germ layer differentiation in the embryo, a process that affects both gastrulation and left-right patterning. By examining candidate genes of congenital heart disease and heterotaxy, we identify KCNH6, a member of the ether-a-go-go class of potassium channels that hyperpolarizes the Vm and thus limits the activation of voltage gated calcium channels, lowering intracellular calcium. In pluripotent embryonic cells, depletion of kcnh6 leads to membrane depolarization, elevation of intracellular calcium levels, and the maintenance of a pluripotent state at the expense of differentiation into ectodermal and myogenic lineages. Using high-resolution temporal transcriptome analysis, we identify the gene regulatory networks downstream of membrane depolarization and calcium signaling and discover that inhibition of the mTOR pathway transitions the pluripotent cell to a differentiated fate. By manipulating Vm using a suite of tools, we establish a bioelectric pathway that regulates pluripotency in vertebrates, including human embryonic stem cells.

Characterizing metastatic uveal melanoma patients who develop symptomatic brain metastases.

Metastatic uveal melanoma (mUM) is an advanced ocular malignancy characterized by a hepatotropic pattern of spread. As the incidence of brain metastases (BM) in mUM patients has been thought to be low, routine CNS surveillance has not been recommended. Notably, no formal assessment of BM incidence in mUM has to date been published to support this clinical practice. We aimed to determine the true rate of BM in mUM and to clarify the clinical and genomic risk factors associated with BM patients through a collaborative multicenter, retrospective research effort. Data collected from 1,845 mUM patients in databases across four NCI-designated comprehensive cancer centers from 2006-2021 were retrospectively analyzed to identify patients with BM. Brain imaging in most cases were performed due to onset of neurological symptoms and not for routine surveillance. An analysis of demographics, therapies, gene expression profile, tumor next generation sequencing (NGS) data, time to metastasis (brain or other), and survival in the BM cohort was completed. 116/1,845 (6.3%) mUM patients were identified with BM. The median age at time of UM diagnosis was 54 years old (range: 18-77). The median time to any metastasis was 4.2 years (range: 0-30.8). The most common initial metastatic site was the liver (75.9%). 15/116 (12.9%) BM patients presented with BM at the time of initial metastatic diagnosis. Median survival after a diagnosis of BM was 7.6 months (range: 0.4-73.9). The median number of organs involved at time of BM diagnosis was 3 (range: 1-9). DecisionDX-UM profiling was completed on 13 patients: 10-Class 2, 2-Class 1B, and 1-Class 1A. NGS and cytogenetic data were available for 34 and 21 patients, respectively. BM was identified in 6.3% of mUM cases and was associated with high disease burden and a median survival of under 8 months once diagnosed. Since most patients in this cohort were symptomatic, the incidence of asymptomatic BM remains unknown. These data suggest the use of routine brain imaging in all mUM patients at risk for developing BM for early detection.

AMPK and Polycystic Kidney Disease Drug Development: An Interesting Off-Target Target.

Autosomal Dominant Polycystic Kidney Disease is a genetic disease that causes dramatic perturbations of both renal tissue architecture and of a multitude of cellular signaling pathways. The relationship between the products of the genes whose mutations cause polycystic kidney disease and these signaling pathways remains difficult to determine. It is clear, however, that cellular metabolism is dramatically altered in cells that are affected by polycystic kidney disease mutations. Adenosine monophosphate-stimulated protein kinase is a master regulator of cellular energy use and generation pathways whose activity appears to be perturbed in cells affected by polycystic kidney disease. Furthermore, modulation of this enzyme's activity may constitute a promising approach for the development of new therapeutics for polycystic kidney disease.

Punch and rescue technique for scleral fixation of dislocated single-piece intraocular lenses.

In-the-bag intraocular lens (IOL) dislocation is a well-known complication after cataract surgery. As the number of cataract surgeries performed annually continues to increase, so will the incidence of IOL dislocations requiring surgical correction. Described is a new technique for rescue and refixation of a single-piece acrylic IOL. In this method, a new instrument called the IOL punch is used to create a hole at the optic-haptic junction or along the border of the optic, which acts as an anchor point for centration and subsequent scleral fixation of a dislocated IOL. The IOL punch allows for precise intraocular manipulation of the IOL and is less invasive compared with popular scleral fixation methods. This innovative technique may decrease the risk for postoperative complications and allows patients to maintain or recover previous uncorrected visual acuity by circumventing the need for IOL explantation or exchange.

ß3 adrenergic receptor as potential therapeutic target in ADPKD.

Autosomal dominant polycystic kidney disease (ADPKD) disrupts renal parenchyma through progressive expansion of fluid-filled cysts. The only approved pharmacotherapy for ADKPD involves the blockade of the vasopressin type 2 receptor (V2R). V2R is a GPCR expressed by a subset of renal tubular cells and whose activation stimulates cyclic AMP (cAMP) accumulation, which is a major driver of cyst growth. The ß3-adrenergic receptor (ß3-AR) is a GPCR expressed in most segments of the murine nephron, where it modulates cAMP production. Since sympathetic nerve activity, which leads to activation of the ß3-AR, is elevated in patients affected by ADPKD, we hypothesize that ß3-AR might constitute a novel therapeutic target. We find that administration of the selective ß3-AR antagonist SR59230A to an ADPKD mouse model (Pkd1fl/fl ;Pax8rtTA ;TetO-Cre) decreases cAMP levels, producing a significant reduction in kidney/body weight ratio and a partial improvement in kidney function. Furthermore, cystic mice show significantly higher ß3-AR levels than healthy controls, suggesting a correlation between receptor expression and disease development. Finally, ß3-AR is expressed in human renal tissue and localizes to cyst-lining epithelial cells in patients. Thus, ß3-AR is a potentially interesting target for the development of new treatments for ADPKD.

Visual and Patient-Reported Outcomes of a Diffractive Trifocal Intraocular Lens Compared with Those of a Monofocal Intraocular Lens.

PURPOSE: To evaluate the effectiveness and safety of a trifocal intraocular lens (IOL), the TFNT00 (Alcon, Fort Worth, TX), versus a monofocal IOL, the SN60AT (Alcon). DESIGN: Food and Drug Administration-approved, prospective, multicenter, nonrandomized, parallel-group, assessor-masked, confirmatory trial. PARTICIPANTS: Patients enrolled were 22 years of age or older with a diagnosis of bilateral cataract with planned removal by phacoemulsification with a clear corneal incision. METHODS: Consented participants selected their preferred IOL, which was implanted sequentially into each eye of patients meeting eligibility criteria. MAIN OUTCOME MEASURES: The coprimary effectiveness outcomes were mean photopic monocular best-corrected distance visual acuity (BCDVA; 4 m) and distance-corrected near visual acuity (DCNVA; 40 cm) at 6 months after surgery. Secondary effectiveness outcomes included mean monocular distance-corrected intermediate visual acuity (DCIVA; 66 cm) and proportion of participants responding "never" to question 1 of the Intraocular Lens Satisfaction questionnaire (regarding frequency of spectacle use in the past 7 days). Safety outcomes included frequency of "severe" and "most bothersome" visual disturbances. RESULTS: Two hundred forty-three patients underwent cataract surgery with bilateral implantation of the TFNT00 (n = 129) or SN60AT (n = 114) and were followed up for 6 months. Noninferiority of TFNT00 to SN60AT in mean photopic monocular BCDVA (95% upper confidence limit of the difference was <0.1 logarithm of the minimum angle of resolution [logMAR] margin), and superiority in mean photopic monocular DCNVA (difference of 0.42 logMAR; P < 0.001) and DCIVA (difference of 0.26 logMAR; P < 0.001) were demonstrated. The proportion of patients never requiring glasses overall was superior for TFNT00 versus SN60AT (80.5% and 8.2%, respectively). Starbursts, halos, and glare were the most frequently rated severe symptoms with TFNT00; however, less than 5% of patients were very bothered at month 6. CONCLUSIONS: The TFNT00 exhibited superior monocular DCNVA and DCIVA to a spherical monofocal IOL, with comparable monocular BCDVA. Binocular visual acuity was 20/25 or better for distance to near (+0.5 D to -2.5 D), resulting in high levels of spectacle independence. Less than 5% of patients were very bothered by the photic visual disturbances associated with the TFNT00 at 6 months after surgery.

Chloride channels regulate differentiation and barrier functions of the mammalian airway.

The conducting airway forms a protective mucosal barrier and is the primary target of airway disorders. The molecular events required for the formation and function of the airway mucosal barrier, as well as the mechanisms by which barrier dysfunction leads to early onset airway diseases, remain unclear. In this study, we systematically characterized the developmental landscape of the mouse airway using single-cell RNA sequencing and identified remarkably conserved cellular programs operating during human fetal development. We demonstrated that in mouse, genetic inactivation of chloride channel Ano1/Tmem16a compromises airway barrier function, results in early signs of inflammation, and alters the airway cellular landscape by depleting epithelial progenitors. Mouse Ano1-/-mutants exhibited mucus obstruction and abnormal mucociliary clearance that resemble the airway defects associated with cystic fibrosis. The data reveal critical and non-redundant roles for Ano1 in organogenesis, and show that chloride channels are essential for mammalian airway formation and function.

Holding open the door reveals a new view of polycystin channel function.

The functions of polycystin 1 and polycystin 2 (PC1 and PC2) have been surprisingly difficult to establish. PC1 and PC2 are encoded by the Pkd1 and Pkd2 genes that are implicated in autosomal dominant polycystic kidney disease (ADPKD). ADPKD is the most common potentially lethal genetic disorder, affecting ~1 in 1,000 people. Over the course of decades, ADPKD patients' kidneys acquire numerous fluid-filled cysts whose expansion compresses the surrounding parenchyma, leading to end-stage renal disease in ~50% of afflicted individuals [1]. Identification of the genes encoding the PC proteins 20 years ago led to the hypothesis that they form an ion channel, since the sequence of PC2 marks it as a member of the TRP family of cation channels. In the ensuing 2 decades, tremendous effort has been devoted to determining whether this is indeed true and, if so, what characteristics that channel might manifest. A recent paper by Wang et al in this issue of EMBO Reports [2] demonstrates that assembly with PC1 changes the properties of the polycystin channel in ways that may help explain the complex behaviors that have been attributed to it.

Can Fish Oil Reduce the Incidence of Necrotizing Enterocolitis by Altering the Inflammatory Response?

Necrotizing enterocolitis (NEC) is a devastating bowel necrosis that predominantly affects preterm infants and is characterized by an imbalance toward a proinflammatory state. Fish oil or omega-3 long-chain polyunsaturated fatty acids have the potential to modulate inflammation. In this article, the authors examine the evidence in support of fish oil supplementation to alter the inflammatory response and potentially reduce the risk of NEC.

Metabolism and mitochondria in polycystic kidney disease research and therapy.

Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common, potentially lethal, monogenic diseases and is caused predominantly by mutations in polycystic kidney disease 1 (PKD1) and PKD2, which encode polycystin 1 (PC1) and PC2, respectively. Over the decades-long course of the disease, patients develop large fluid-filled renal cysts that impair kidney function, leading to end-stage renal disease in ~50% of patients. Despite the identification of numerous dysregulated pathways in ADPKD, the molecular mechanisms underlying the renal dysfunction from mutations in PKD genes and the physiological functions of the polycystin proteins are still unclear. Alterations in cell metabolism have emerged in the past decade as a hallmark of ADPKD. ADPKD cells shift their mode of energy production from oxidative phosphorylation to alternative pathways, such as glycolysis. In addition, the polycystins seem to play regulatory roles in modulating mechanisms and machinery related to energy production and utilization, including AMPK, PPARα, PGC1α, calcium signalling at mitochondria-associated membranes, mTORC1, cAMP and CFTR-mediated ion transport as well as the expression of crucial components of the mitochondrial energy production apparatus. In this Review, we explore these metabolic changes and discuss in detail the relationship between energy metabolism and ADPKD pathogenesis and identify potential therapeutic targets.

Newly synthesized polycystin-1 takes different trafficking pathways to the apical and ciliary membranes.

Mutations in the genes encoding polycystin-1 (PC1) and polycystin 2 (PC2) cause autosomal dominant polycystic kidney disease. These transmembrane proteins colocalize in the primary cilia of renal epithelial cells, where they may participate in sensory processes. PC1 is also found in the apical membrane when expressed in cultured epithelial cells. PC1 undergoes autocatalytic cleavage, producing an extracellular N-terminal fragment that remains noncovalently attached to the transmembrane C-terminus. Exposing cells to alkaline solutions elutes the N-terminal fragment while the C-terminal fragment is retained in the cell membrane. Utilizing this observation, we developed a "strip-recovery" synchronization protocol to study PC1 trafficking in polarized LLC-PK1 renal epithelial cells. Following alkaline strip, a new cohort of PC1 repopulates the cilia within 30 minutes, while apical delivery of PC1 was not detectable until 3 hours. Brefeldin A (BFA) blocked apical PC1 delivery, while ciliary delivery of PC1 was BFA insensitive. Incubating cells at 20°C to block trafficking out of the trans-Golgi network also inhibits apical but not ciliary delivery. These results suggest that newly synthesized PC1 takes distinct pathways to the ciliary and apical membranes. Ciliary PC1 appears to by-pass BFA sensitive Golgi compartments, while apical delivery of PC1 traverses these compartments.

Implications of AMPK in the Formation of Epithelial Tight Junctions.

Tight junctions (TJ) play an essential role in the epithelial barrier. By definition, TJ are located at the demarcation between the apical and baso-lateral domains of the plasma membrane in epithelial cells. TJ fulfill two major roles: (i) TJ prevent the mixing of membrane components; and (ii) TJ regulate the selective paracellular permeability. Disruption of TJ is regarded as one of the earliest hallmarks of epithelial injury, leading to the loss of cell polarity and tissue disorganization. Many factors have been identified as modulators of TJ assembly/disassembly. More specifically, in addition to its role as an energy sensor, adenosine monophosphate-activated protein kinase (AMPK) participates in TJ regulation. AMPK is a ubiquitous serine/threonine kinase composed of a catalytic α-subunit complexed with regulatory ß-and γ-subunits. AMPK activation promotes the early stages of epithelial TJ assembly. AMPK phosphorylates the adherens junction protein afadin and regulates its interaction with the TJ-associated protein zonula occludens (ZO)-1, thereby facilitating ZO-1 distribution to the plasma membrane. In the present review, we detail the signaling pathways up-and down-stream of AMPK activation at the time of Ca2+-induced TJ assembly.

In Vitro Validation of Targeting and Comparison to Mathematical Modeling.

Nanoparticle and other drug delivery platforms have demonstrated promising potential for the delivery of therapeutics or imaging agents in a specific and targeted manner. While a variety of drug delivery platforms have been applied to medicine, in vitro and in silico optimization and validation of these targeting constructs needs to be conducted to maximize in vivo delivery and efficacy. Here, we describe the mathematical and experimental models to predict and validate the transport of a peptide targeting construct through a mock tissue environment to specifically target tumor cells, relative to non-tumor cells. We provide methods to visualize and analyze fluorescence microscopy images, and also describe the methods for creating a finite element model (FEM) that validates important parameters of this experimental system. By comparing and contrasting mathematical modeling results with experimental results, important information can be imparted to the design and functionality of the targeting construct. This information will help to optimize construct design for future therapeutic delivery applications.

Tandem Histone-Binding Domains Enhance the Activity of a Synthetic Chromatin Effector.

Fusion proteins that specifically interact with biochemical marks on chromosomes represent a new class of synthetic transcriptional regulators that decode cell state information rather than DNA sequences. In multicellular organisms, information relevant to cell state, tissue identity, and oncogenesis is often encoded as biochemical modifications of histones, which are bound to DNA in eukaryotic nuclei and regulate gene expression states. We have previously reported the development and validation of the "polycomb-based transcription factor" (PcTF), a fusion protein that recognizes histone modifications through a protein-protein interaction between its polycomb chromodomain (PCD) motif and trimethylated lysine 27 of histone H3 (H3K27me3) at genomic sites. We demonstrated that PcTF activates genes at methyl-histone-enriched loci in cancer-derived cell lines. However, PcTF induces modest activation of a methyl-histone associated reporter compared to a DNA-binding activator. Therefore, we modified PcTF to enhance its binding avidity. Here, we demonstrate the activity of a modified regulator called Pc2TF, which has two tandem copies of the H3K27me3-binding PCD at the N-terminus. Pc2TF has a smaller apparent dissociation constant value in vitro and shows enhanced gene activation in HEK293 cells compared to PcTF. These results provide compelling evidence that the intrinsic histone-binding activity of the PCD motif can be used to tune the activity of synthetic histone-binding transcriptional regulators.

Necrotizing enterocolitis: Pathophysiology from a historical context.

Necrotizing enterocolitis (NEC) continues to afflict approximately 7% of preterm infants born weighing less than 1500g, though recent investigations have provided novel insights into the pathogenesis of this complex disease. The disease has been a major cause of morbidity and mortality in neonatal intensive care units worldwide for many years, and our current understanding reflects exceptional observations made decades ago. In this review, we will describe NEC from a historical context and summarize seminal findings that underscore the importance of enteral feeding, the gut microbiota, and intestinal inflammation in this complex pathophysiology.

New Medical and Surgical Insights Into Neonatal Necrotizing Enterocolitis: A Review.

Importance: Necrotizing enterocolitis (NEC) has long remained a significant cause of morbidity and mortality in neonatal intensive care units. While the mainstay of treatment for this devastating condition remains largely supportive, research efforts continue to be directed toward understanding pathophysiology as well as how best to approach surgical management when indicated. Observations: In this review, we first examine recent medical observations, including overviews on the microbiome and a brief review of the use of probiotics. Next, we discuss the use of biomarkers and how clinicians may be able to use them in the future to predict the course of disease and, perhaps, the need for surgical intervention. We then provide an overview on the use of exclusive human milk feeding and the utility of this approach in preventing NEC. Finally, we discuss recent developments in the surgical management of NEC, beginning with indications for surgery and following with a section on technical surgical considerations, including peritoneal drain vs laparotomy. The review concludes with outcomes from infants with surgically treated NEC. Conclusions and Relevance: Although medical treatment options for NEC are largely unchanged, understanding of the disease continues to evolve. As new research methods are developed, NEC pathophysiology can be more completely understood. In time, it is hoped that data from ongoing and planned clinical trials will allow us to routinely add targeted preventive measures in addition to human milk, such as prebiotics and probiotics, to the management of high-risk infants. In addition, the discovery of novel biomarkers may not only prove useful in predicting severity of illness but also will hopefully allow for identification of the disease prior to onset of clinical signs. Finally, continued investigation into optimizing surgical outcomes is essential in this population of infants, many of whom require long-term parenteral therapy and intestinal rehabilitation.

The periciliary ring in polarized epithelial cells is a hot spot for delivery of the apical protein gp135.

In polarized epithelial cells, newly synthesized cell surface proteins travel in carrier vesicles from the trans Golgi network to the apical or basolateral plasma membrane. Despite extensive research on polarized trafficking, the sites of protein delivery are not fully characterized. Here we use the SNAP tag system to examine the site of delivery of the apical glycoprotein gp135. We show that a cohort of gp135 is delivered to a ring surrounding the base of the primary cilium, followed by microtubule-dependent radial movement away from the cilium. Delivery to the periciliary ring was specific to newly synthesized and not recycling protein. A subset of this newly delivered protein traverses the basolateral membrane en route to the apical membrane. Crumbs3a, another apical protein, was not delivered to the periciliary region, instead making its initial apical appearance in a pattern that resembled its steady-state distribution. Our results demonstrate a surprising "hot spot" for gp135 protein delivery at the base of the primary cilium and suggest the existence of a novel microtubule-based directed movement of a subset of apical surface proteins.