The Retinal Ganglion Cell Repopulation, Stem Cell Transplantation, and Optic Nerve Regeneration Consortium.

Purpose: The Retinal Ganglion Cell (RGC) Repopulation, Stem Cell Transplantation, and Optic Nerve Regeneration (RReSTORe) consortium was founded in 2021 to help address the numerous scientific and clinical obstacles that impede development of vision-restorative treatments for patients with optic neuropathies. The goals of the RReSTORe consortium are: (1) to define and prioritize the most critical challenges and questions related to RGC regeneration; (2) to brainstorm innovative tools and experimental approaches to meet these challenges; and (3) to foster opportunities for collaborative scientific research among diverse investigators. Design and Participants: The RReSTORe consortium currently includes > 220 members spanning all career stages worldwide and is directed by an organizing committee comprised of 15 leading scientists and physician-scientists of diverse backgrounds. Methods: Herein, we describe the structure and organization of the RReSTORe consortium, its activities to date, and the perceived impact that the consortium has had on the field based on a survey of participants. Results: In addition to helping propel the field of regenerative medicine as applied to optic neuropathies, the RReSTORe consortium serves as a framework for developing large collaborative groups aimed at tackling audacious goals that may be expanded beyond ophthalmology and vision science. Conclusions: The development of innovative interventions capable of restoring vision for patients suffering from optic neuropathy would be transformative for the ophthalmology field, and may set the stage for functional restoration in other central nervous system disorders. By coordinating large-scale, international collaborations among scientists with diverse and complementary expertise, we are confident that the RReSTORe consortium will help to accelerate the field toward clinical translation. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Retinal ganglion cell repopulation for vision restoration in optic neuropathy: a roadmap from the RReSTORe Consortium.

Retinal ganglion cell (RGC) death in glaucoma and other optic neuropathies results in irreversible vision loss due to the mammalian central nervous system's limited regenerative capacity. RGC repopulation is a promising therapeutic approach to reverse vision loss from optic neuropathies if the newly introduced neurons can reestablish functional retinal and thalamic circuits. In theory, RGCs might be repopulated through the transplantation of stem cell-derived neurons or via the induction of endogenous transdifferentiation. The RGC Repopulation, Stem Cell Transplantation, and Optic Nerve Regeneration (RReSTORe) Consortium was established to address the challenges associated with the therapeutic repair of the visual pathway in optic neuropathy. In 2022, the RReSTORe Consortium initiated ongoing international collaborative discussions to advance the RGC repopulation field and has identified five critical areas of focus: (1) RGC development and differentiation, (2) Transplantation methods and models, (3) RGC survival, maturation, and host interactions, (4) Inner retinal wiring, and (5) Eye-to-brain connectivity. Here, we discuss the most pertinent questions and challenges that exist on the path to clinical translation and suggest experimental directions to propel this work going forward. Using these five subtopic discussion groups (SDGs) as a framework, we suggest multidisciplinary approaches to restore the diseased visual pathway by leveraging groundbreaking insights from developmental neuroscience, stem cell biology, molecular biology, optical imaging, animal models of optic neuropathy, immunology & immunotolerance, neuropathology & neuroprotection, materials science & biomedical engineering, and regenerative neuroscience. While significant hurdles remain, the RReSTORe Consortium's efforts provide a comprehensive roadmap for advancing the RGC repopulation field and hold potential for transformative progress in restoring vision in patients suffering from optic neuropathies.

VATS Uniportal, masterclass Guatemala / VATS Uniportal, masterclass Guatemala

En las dos últimas décadas la evolución de la cirugía mínimamente invasiva del tórax ha transmutado de un abordaje de tres puertos, siguiendo dos puertos hasta llegar a puerto único, conocido también como VATS Uniportal, procurando un confort mucho mejor para el paciente y resultados quirúrgicos similares. Objetivos. Presentar la técnica quirúrgica de VATS Uniportal en un hospital nacional, efectuadas por un experto internacional en este campo. Pacientes y Métodos. Se presentan dos casos clínicos quirúrgicos: El de una paciente con Miastenia Gravis a quien se le realizó timectomía por abordaje sub-xifoideo y otra paciente, a quien se le completó una lobectomía inferior derecha por hallazgos de patología posterior a la resección de un nódulo pulmonar solitario, reportado como cáncer primario de pulmón. Conclusiones. La técnica de cirugía mínimamente invasiva, VATS Uniportal, ofrece grandes beneficios para el paciente, tanto estéticos como funcionales y su aprendizaje es posible con la transmisión de conocimientos y experiencias directa con la presencia del experto o indirectas a través de la información publicada. (AU)

In the last two decades, the evolution of minimally invasive chest surgery has transmuted from a three-port approach, following two ports until reaching a single port, also known as VATS Uniportal, seeking much better comfort for the patient and similar surgical results. Objective. Present the VATS Uniportal surgical technique in a national hospital, performed by an international expert in this field. Patients and Methods. Two surgical clinical cases are presented: that of a patient with Myasthenia Gravis who underwent thymectomy through the sub-xiphoid approach and another patient, who underwent a right lower lobectomy due to findings of pathology after the resection of a pulmonary nodule. solitary, reported as primary lung cancer. Conclusions. The minimally invasive surgery technique, VATS Uniportal, offers great benefits for the patient, both aesthetic and functional and its learning is possible with the transmission of knowledge and experiences directly with the presence of the expert or indirectly through published information. (AU)

Chronic optical pacing conditioning of h-iPSC engineered cardiac tissues.

The immaturity of human induced pluripotent stem cell derived engineered cardiac tissues limits their ability to regenerate damaged myocardium and to serve as robust in vitro models for human disease and drug toxicity studies. Several chronic biomimetic conditioning protocols, including mechanical stretch, perfusion, and/or electrical stimulation promote engineered cardiac tissue maturation but have significant technical limitations. Non-contacting chronic optical stimulation using heterologously expressed channelrhodopsin light-gated ion channels, termed optogenetics, may be an advantageous alternative to chronic invasive electrical stimulation for engineered cardiac tissue conditioning. We designed proof-of-principle experiments to successfully transfect human induced pluripotent stem cell derived engineered cardiac tissues with a desensitization resistant, chimeric channelrhodopsin protein, and then optically paced engineered cardiac tissues to accelerate maturation. We transfected human induced pluripotent stem cell engineered cardiac tissues using an adeno-associated virus packaged chimeric channelrhodopsin and then verified optically paced by whole cell patch clamp. Engineered cardiac tissues were then chronically optically paced above their intrinsic beat rates in vitro from day 7 to 14. Chronically optically paced resulted in improved engineered cardiac tissue electrophysiological properties and subtle changes in the expression of some cardiac relevant genes, though active force generation and histology were unchanged. These results validate the feasibility of a novel chronically optically paced paradigm to explore non-invasive and scalable optically paced-induced engineered cardiac tissue maturation strategies.

Initial experience in uniportal subxiphoid video-assisted thoracoscopic surgery for major lung resections.

OBJECTIVES: Uniportal subxiphoid video-assisted thoracoscopic (SVATS) surgery for major lung resections is a new approach, but clinical evidence is lacking. The aim of this study was to examine our experience with the use of the uniportal subxiphoid approach in video-assisted thoracoscopic (VATS) major lung resections and lymph node dissections. METHODS: From October 2014 to August 2015, 153 patients with early-stage non-small-cell lung carcinoma (NSCLC) and benign disease underwent uniportal subxiphoid VATS major lung resections. Patients were placed in a lateral position with 60-70° inclination, and a 4- to 5-cm midline median or transverse incision was made below the sternocostal triangle. A 10-mm 30° video camera and VATS instruments were used through the same single incision. Perioperative variables and outcomes were collected prospectively and analysed retrospectively. RESULTS: Of the 153 patients who underwent surgery with the uniportal subxiphoid VATS approach, 105 had lobectomies and 48 had segmental resections; 135 cases of lung cancer and 18 cases of benign pulmonary disease were noted. Right upper lobectomy was the most common procedure (51%), and left upper lobectomy was the most time-consuming procedure (190 ± 21 min). The mean operating time was 166.9 ± 12.6 min; the average volume of blood loss was 127.5 ± 27.6 ml. In patients with lung cancer, the mean total number of lymph node stations explored was 3.4 ± 0.8. The duration of chest drain use was 2.6 ± 0.2 days. The length of hospital stay was 4.3 ± 0.4 days. Perioperative arrhythmia was the most common complication (13% of cases). Prolonged air leak was the cause of prolonged hospital stay. Five cases were converted to conventional VATS due to technical difficulties, and eight cases were converted to thoracotomy due to major bleeding. Postoperative 30-day mortality was zero and there were no re-admissions. All cases had a R0 complete cancer resection on histology. CONCLUSIONS: Uniportal subxiphoid VATS lobectomy/segmentectomy is a feasible and safe procedure for early-stage lung cancer and benign disease.

Report on the National Eye Institute Audacious Goals Initiative: Regenerating the Optic Nerve.

The National Eye Institute (NEI) hosted a workshop on November 19, 2014, as part of the Audacious Goals Initiative (AGI), an NEI-led effort to rapidly expand therapies for eye diseases through coordinated research funding. The central audacious goal aims to demonstrate by 2025 the restoration of usable vision in humans through the regeneration of neurons and neural connections in the eye and visual system. This workshop focused on identifying promising strategies for optic nerve regeneration. Its principal objective was to solicit input on future AGI-related funding announcements, and specifically to ask, where are we now in our scientific progress, and what progress should we reach for in the coming years? A full report was generated as a white paper posted on the NEI Web site; this report summarizes the discussion and outcomes from the meeting and serves as guidance for future funding of research that focuses on optic nerve regeneration.

Learning curve and subxiphoid lung resections most common technical issues.

BACKGROUND: Subxiphoid uniportal video-assisted thoracic surgery (SVATS) for major lung resections is a new approach. Clinical evidence is lacking. The aim of this article is to describe the learning curve of the 200 selected patients who underwent uniportal subxiphoid lobectomy or segmentectomy by subxiphoid midline incision, and with the lessons learned from this early experience in SVATS and from the experience with transthoracic uniportal VATS we sought to compile "tips and tricks" for managing the multiple intraoperative technical difficulties that can arise during the SVATS and help to set the recommendations for a SVATS program. METHODS: We describe the learning curve of the first 200 selected patients who underwent uniportal subxiphoid lobectomy or segmentectomy by subxiphoid midline incision From September 2014 with early-stage non-small cell lung carcinoma (NSCLC) and benign disease. We examine the rate of conversion and the operating time comparing group one (first 100 cases) with group two (subsequent 100 cases). RESULTS: Of the 200 consecutive selected cases (72 males, 128 females) with a mean age of 57.4±9 years, underwent either uniportal subxiphoid lobectomy or segmentectomy 136 were lobectomies and 64 were segmental resections The mean operating time was 170±45 mins; the average and after the case 86 the rate of the operating time appears to be similar. The conversion rate decrease from 13% in group one to 8% in group two. CONCLUSIONS: There is a gradual reduction in the operating time and rate conversion with increasing experience. Lessons from our initial experience in the learning curve period in SVATS helps to create this trouble shooting guide that offers "tips and tricks" to both avoid and manage numerous intra-operative technical difficulties that commonly arise during the SVATS initial experience.

Uniportal video-assisted thoracoscopic right upper sleeve lobectomy.

BACKGROUND: The development of minimally invasive thoracic surgery in recent years is undeniable, VATS has evolved from the conventional three-port technique to an uniportal approach, without compromising the type of cases that can be operated successfully. METHODS: Thanks to the continuous progress of uniportal video-assisted thoracoscopic surgery (VATS) the complexity of cases performed by this approach has improved remarkably since the first procedures were made, recent advances in surgical thoracoscopic technology had made feasible to achieve vascular and bronchial sleeve lobectomies. Anatomic variants in patients can increase the technical difficulty of the procedure making the process more challenging. RESULTS: In this case the sleeve right upper lobectomy was performed by uniportal VATS despite the obstruction of the right pulmonary artery (PA) for the bronchial anastomosis. CONCLUSIONS: In the hands of experienced surgeons in uniportal VATS with background in thoracoscopic suturing, sleeve lobectomies are feasible and safe to perform even when anatomic variants increase the complexity of the case.

Retinal input regulates the timing of corticogeniculate innervation.

Neurons in layer VI of visual cortex represent one of the largest sources of nonretinal input to the dorsal lateral geniculate nucleus (dLGN) and play a major role in modulating the gain of thalamic signal transmission. However, little is known about how and when these descending projections arrive and make functional connections with dLGN cells. Here we used a transgenic mouse to visualize corticogeniculate projections to examine the timing of cortical innervation in dLGN. Corticogeniculate innervation occurred at postnatal ages and was delayed compared with the arrival of retinal afferents. Cortical fibers began to enter dLGN at postnatal day 3 (P3) to P4, a time when retinogeniculate innervation is complete. However, cortical projections did not fully innervate dLGN until eye opening (P12), well after the time when retinal inputs from the two eyes segregate to form nonoverlapping eye-specific domains. In vitro thalamic slice recordings revealed that newly arriving cortical axons form functional connections with dLGN cells. However, adult-like responses that exhibited paired pulse facilitation did not fully emerge until 2 weeks of age. Finally, surgical or genetic elimination of retinal input greatly accelerated the rate of corticogeniculate innervation, with axons invading between P2 and P3 and fully innervating dLGN by P8 to P10. However, recordings in genetically deafferented mice showed that corticogeniculate synapses continued to mature at the same rate as controls. These studies suggest that retinal and cortical innervation of dLGN is highly coordinated and that input from retina plays an important role in regulating the rate of corticogeniculate innervation.

Apoptosis regulates ipRGC spacing necessary for rods and cones to drive circadian photoentrainment.

The retina consists of ordered arrays of individual types of neurons for processing vision. Here, we show that such order is necessary for intrinsically photosensitive retinal ganglion cells (ipRGCs) to function as irradiance detectors. We found that during development, ipRGCs undergo proximity-dependent Bax-mediated apoptosis. Bax mutant mice exhibit disrupted ipRGC spacing and dendritic stratification with an increase in abnormally localized synapses. ipRGCs are the sole conduit for light input to circadian photoentrainment, and either their melanopsin-based photosensitivity or ability to relay rod/cone input is sufficient for circadian photoentrainment. Remarkably, the disrupted ipRGC spacing does not affect melanopsin-based circadian photoentrainment but severely impairs rod/cone-driven photoentrainment. We demonstrate reduced rod/cone-driven cFos activation and electrophysiological responses in ipRGCs, suggesting that impaired synaptic input to ipRGCs underlies the photoentrainment deficits. Thus, for irradiance detection, developmental apoptosis is necessary for the spacing and connectivity of ipRGCs that underlie their functioning within a neural network.

Optogenetic stimulation of the corticothalamic pathway affects relay cells and GABAergic neurons differently in the mouse visual thalamus.

The dorsal lateral geniculate nucleus (dLGN) serves as the primary conduit of retinal information to visual cortex. In addition to retinal input, dLGN receives a large feedback projection from layer VI of visual cortex. Such input modulates thalamic signal transmission in different ways that range from gain control to synchronizing network activity in a stimulus-specific manner. However, the mechanisms underlying such modulation have been difficult to study, in part because of the complex circuitry and diverse cell types this pathway innervates. To address this and overcome some of the technical limitations inherent in studying the corticothalamic (CT) pathway, we adopted a slice preparation in which we were able to stimulate CT terminal arbors in the visual thalamus of the mouse with blue light by using an adeno-associated virus to express the light-gated ion channel, ChIEF, in layer VI neurons. To examine the postsynaptic responses evoked by repetitive CT stimulation, we recorded from identified relay cells in dLGN, as well as GFP expressing GABAergic neurons in the thalamic reticular nucleus (TRN) and intrinsic interneurons of dLGN. Relay neurons exhibited large glutamatergic responses that continued to increase in amplitude with each successive stimulus pulse. While excitatory responses were apparent at postnatal day 10, the strong facilitation noted in adult was not observed until postnatal day 21. GABAergic neurons in TRN exhibited large initial excitatory responses that quickly plateaued during repetitive stimulation, indicating that the degree of facilitation was much larger for relay cells than for TRN neurons. The responses of intrinsic interneurons were smaller and took the form of a slow depolarization. These differences in the pattern of excitation for different thalamic cell types should help provide a framework for understanding how CT feedback alters the activity of visual thalamic circuitry during sensory processing as well as different behavioral or pathophysiological states.

Loss of binocular responses and reduced retinal convergence during the period of retinogeniculate axon segregation.

In the developing mammalian visual system, axon terminals from the two eyes overlap in the dorsal lateral geniculate nucleus (LGN) but then undergo a period of refinement and segregate to form distinct eye-specific domains. We report on the changes in synaptic transmission that occur in rodent LGN during the period of retinogeniculate axon segregation by using anterograde labeling techniques in conjunction with an in vitro preparation where large segments of each optic nerve are preserved. Anterograde labeling of retinal projections in early postnatal day (P) rats with cholera toxin beta subunit indicated an age-related recession in uncrossed retinal projections. Between P2 and P5 uncrossed projections occupied as much as 50% of the LGN and overlapped substantially with crossed projections. Between the first and second postnatal week uncrossed projections receded, so by P14 they assumed an adultlike profile occupying 15-20% of LGN and showed little or no overlap with crossed projections. The postsynaptic responses of LGN cells evoked by the separate stimulation of each optic nerve indicated that before P14, many relay cells were binocularly innervated and received at least four to six inputs from each eye. However, these features of retinogeniculate connectivity were transient and their attrition occurred in concert with a retraction of retinal arbors into nonoverlapping, eye-specific regions. By P18 cells were monocularly innervated and received input from one to three retinal ganglion cells. These results provide a better understanding of the underlying changes in synaptic circuitry that occur during the anatomical segregation of retinal inputs into eye-specific territories.