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IScience May 2021Beginning of metastasis, cancer cells detach from the primary tumor and they can survive even under loss of anchorage; however, the detachment-elicited mechanisms have...
Beginning of metastasis, cancer cells detach from the primary tumor and they can survive even under loss of anchorage; however, the detachment-elicited mechanisms have remained unknown. Here, we found that Na,K-ATPase α3-isoform (α3NaK) in human cancer cells is dynamically translocated from intracellular vesicles to the plasma membrane when the attached cells are detached and that this mechanism contributes to the survival of the detached (floating) cancer cells. α3NaK was detected in the plasma membrane of floating cancer cells in peritoneal fluids of patients, while it was in the cytoplasm of the cells in primary tumor tissues. On cancer cell detachment, we also found the focal-adhesion-kinase-dependent Ca response that induces the α3NaK translocation via nicotinic acid adenine dinucleotide phosphate pathway. Activation of AMP-activated protein kinase was associated with the translocated α3NaK in the plasma membrane. Collectively, our study identifies a unique mechanism for survival of detached cancer cells, opening up new opportunities for development of cancer medicines.
PubMed: 33997694
DOI: 10.1016/j.isci.2021.102412 -
The British Journal of Ophthalmology Jan 2022Graft detachment is the most common complication of endothelial keratoplasty. With the ongoing advancements in the field of endothelial keratoplasty, our understanding... (Review)
Review
Graft detachment is the most common complication of endothelial keratoplasty. With the ongoing advancements in the field of endothelial keratoplasty, our understanding of risk factors of graft detachments and its management has been evolving. Various prevention measures have been described in literature including presoaking the donor graft, anterior chamber tamponade, venting incisions, sutures to prevent dislocation of graft. Management of a detached graft involves secondary interventions such as rebubbling, suturing and regrafts. In this review, we discuss graft detachment in different types of endothelial keratoplasty techniques including Descemet stripping endothelial keratoplasty, Descemet stripping automated endothelial keratoplasty and Descemet's membrane endothelial keratoplasty; with emphasis on incidence, risk factors, preventive measures and their management.
Topics: Anterior Chamber; Descemet Membrane; Descemet Stripping Endothelial Keratoplasty; Endothelium, Corneal; Graft Survival; Humans; Postoperative Complications; Visual Acuity
PubMed: 33397659
DOI: 10.1136/bjophthalmol-2020-318092 -
Survey of Ophthalmology 2014A giant retinal tear (GRT) is a full-thickness neurosensory retinal break that extends circumferentially around the retina for three or more clock hours in the presence... (Review)
Review
A giant retinal tear (GRT) is a full-thickness neurosensory retinal break that extends circumferentially around the retina for three or more clock hours in the presence of a posteriorly detached vitreous. Its incidence in large population-based studies has been estimated as 1.5% of rhegmatogenous retinal detachments, with a significant male preponderance, and bilaterality in 12.8%. Most GRTs are idiopathic, with trauma, hereditary vitreoretinopathies and high myopia each being causative in decreasing frequency. The vast majority of GRTs are currently managed with a pars plana vitrectomy; the use of adjunctive circumferential scleral buckling is debated, but no studies have shown a clear anatomical or visual advantage with its use. Similarly, silicone oil tamponade does not influence long-term outcomes when compared with gas. Primary and final retinal reattachment rates are achieved in 88% and 95% of patients, respectively. Even when the retina remains attached, however, visual recovery may be limited. Furthermore, fellow eyes of patients with a GRT are at higher risk of developing retinal tears and retinal detachment. Prophylactic treatment under these circumstances may be considered but there is no firm evidence of its efficacy at the present time.
Topics: Cataract Extraction; Diagnosis, Differential; Eye Injuries; Humans; Phacoemulsification; Retinal Perforations; Risk Factors; Vitrectomy
PubMed: 24138895
DOI: 10.1016/j.survophthal.2013.03.006 -
The British Journal of Ophthalmology Jun 1981Ripping of detached pigment epithelium appears to be a common sight-threatening complication of pigment epithelial detachments and occurs at the junction of the...
Ripping of detached pigment epithelium appears to be a common sight-threatening complication of pigment epithelial detachments and occurs at the junction of the detachment and flat pigment epithelium. The characteristics of the detachment prior to the rip suggest that the tear occurs in pigment epithelium which is detached without its basement membrane. The tear is followed by retraction of the pigment epithelium, revealing bare Bruch's membrane. The defect may remain apparently unaltered, or may be recovered by normal looking pigment epithelium, but most commonly is replaced by a fibrous plaque. Most patients had a profound reduction in visual acuity.
Topics: Aged; Female; Fluorescein Angiography; Humans; Male; Middle Aged; Pigment Epithelium of Eye; Retinal Detachment; Visual Acuity
PubMed: 7260013
DOI: 10.1136/bjo.65.6.417 -
Anatomical Sciences Education May 2016The cadaver dissection course remains a time-honored tradition in medical education, partly because of its importance in cultivating professional attitudes in students....
The cadaver dissection course remains a time-honored tradition in medical education, partly because of its importance in cultivating professional attitudes in students. This study aims to investigate students' attitudes-specifically characterized as "detached concern"-in a cadaver dissection course. An interpretative phenomenological analysis was performed with semi-structured, focus group interviews among 12 third-year medical students from a Taiwanese medical school to reveal their perceptions and learning experiences regarding human cadaver dissection. Based on these interviews, four relevant categories of perspectives were delineated: (1) initial emotional impact, (2) human referents, (3) coping strategies, and (4) ways of perceiving cadavers. Students were divided into two groups based on these categories. Students in Group 1 developed mechanisms described as "detachment" to cope with their initial emotional reactions to cadaveric dissection, which was noted to have disruptive effects on their learning. They considered human referents to be learning obstacles and avoided contact with or thinking about the human referents while performing dissections. Some of them faced a conflict between perceiving the cadaver as a learning tool versus as a human being. This impasse could be resolved if they latently adopted a "perspective switch" between the concept of a learning tool (rational aspect) and a human being (sensitive aspect). The students in Group 2 had no obvious initial emotional reaction. For them, the human referents functioned as learning supports, and the cadavers were consistently perceived as humans. These students held the notion that "cadaver dissection is an act of love"; therefore, they did not experience any need to detach themselves from their feelings during dissection. This alternative attitude revealed that detached concern alone is not sufficient to describe the entire range of medical students' attitudes toward cadaver dissection. Anat Sci Educ 9: 265-271. © 2015 American Association of Anatomists.
Topics: Anatomy; Cadaver; Female; Humans; Male; Students, Medical; Young Adult
PubMed: 26587913
DOI: 10.1002/ase.1579 -
Seminars in Ophthalmology 2018Scleral buckling has an important role in the repair of certain categories of rhegmatogenous retinal detachments. These include detachments in young phakic patients,... (Review)
Review
Scleral buckling has an important role in the repair of certain categories of rhegmatogenous retinal detachments. These include detachments in young phakic patients, detachments associated with dialysis, and also in conjuction with vitrectomy in patients who have sustained trauma or have developed proliferative vitreoretinopathy. However, it can be associated with significant postoperative complications. The most important ones are refractive change, intrusion or extrusion, infection, globe ischemia, and choroidal detachments, amongst others. Careful planning, appropriate patient selection, and good intraoperative technique can reduce the rate of these complications.
Topics: Humans; Postoperative Complications; Retinal Detachment; Scleral Buckling; Visual Acuity
PubMed: 29185844
DOI: 10.1080/08820538.2017.1353816 -
Praxis Aug 2015Acute vision loss, a painful eye, or a red/pink eye are typical symptoms of an ophthalmic emergency. Ascertain a thorough medical history concerning type, duration, and... (Review)
Review
Acute vision loss, a painful eye, or a red/pink eye are typical symptoms of an ophthalmic emergency. Ascertain a thorough medical history concerning type, duration, and location of visual loss to point out the etiology of the disease. With simple diagnostic tools the differential diagnosis can be narrowed down even by non-ophthalmologists. This first differential diagnosis shows how urgent the patient has to be referred to an ophthalmologist.
Topics: Conjunctivitis; Diagnosis, Differential; Emergencies; Eye Diseases; Eye Pain; Humans; Vision Disorders
PubMed: 26242419
DOI: 10.1024/1661-8157/a002087 -
Journal Francais D'ophtalmologie Mar 2006Floating membranes are epiretinal membranes that spontaneously detach from the retina and float in the vitreous cavity.
INTRODUCTION
Floating membranes are epiretinal membranes that spontaneously detach from the retina and float in the vitreous cavity.
PATIENTS AND METHOD
We studied a series of nine patients with a spontaneous separation of a premacular membrane. The majority of these detached membranes were secondary to vitreomacular traction syndrome. In four patients, the presence of peripheral retinal tears treated in the past by laser photocoagulation were found. None of the patients had complete vitreoretinal detachment before progressing to floating membranes.
RESULTS
The separation of the membrane from the macular area occurred at the time of posterior vitreous detachment. The appearance of a bulky intravitreous floating body attached to the posterior vitreous cortex sometimes proved to be very awkward for vision, resulting in a vitrectomy in four patients for ablation of this large floating body. In five patients who were not operated, the presence of the membrane in the vitreous cavity was not responsible for significant functional disorders.
DISCUSSION
The epimacular membranes concerned in this series were not very symptomatic before their detachment. They seemed to be integrated within the context of vitreomacular traction syndrome. The most invalidating cases that required surgery were those where the separation of the vitreous cortex remained incomplete, leaving an opaque membrane floating with a little mobility in front of the macular area (three out of four cases).
CONCLUSION
The spontaneous detachment of a premacular membrane is an event that is quite seldom observed and generally follows the spontaneously favorable progression of vitreomacular traction syndrome.
Topics: Aged; Female; Humans; Male; Middle Aged; Retinal Detachment
PubMed: 16557174
DOI: 10.1016/s0181-5512(06)73786-x -
Survey of Ophthalmology 1985Proliferative vitreoretinopathy (PVR) is a disease process that occurs in eyes with rhegmatogenous retinal detachments and accounts for the majority of failures... (Review)
Review
Proliferative vitreoretinopathy (PVR) is a disease process that occurs in eyes with rhegmatogenous retinal detachments and accounts for the majority of failures following retinal detachment surgery. PVR involves the uncontrolled proliferation of non-neoplastic cells capable of forming membranes, which may occur on either surface of the retina or along the detached surface of the vitreous gel. Contraction of these membranes creates tractional forces that can distort or detach the retina. Various surgical procedures have been used to repair retinal detachments associated with PVR. The results have not been encouraging in many instances. Recent efforts have been directed toward the chemical inhibition of cellular proliferation in PVR. The majority of drugs used in these studies have been antineoplastic agents that affect various phases in the cycle of cell growth.
Topics: Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Cell Division; Eye Diseases; Half-Life; Humans; Rabbits; Retinal Detachment; Retinal Diseases; Vitreous Body
PubMed: 3892742
DOI: 10.1016/0039-6257(85)90208-5 -
Current Eye Research Jan 1997Long-term results, more than 10 years after successful retinal detachment surgery, have shown gradually decreasing visual acuity in some cases. It is unclear if reduced...
PURPOSE
Long-term results, more than 10 years after successful retinal detachment surgery, have shown gradually decreasing visual acuity in some cases. It is unclear if reduced functional recovery postoperatively is caused by anatomic changes or biochemical disorders. To determine the etiology of the reduced visual acuity, we cytochemically examined the changes in the cellular responses of the edges of retinal detachments.
METHODS
We histochemically studied the glucose-6-phosphatase (G6P) and 5'-nucleotidase (5'-Nase) activity in the rabbit retina. Experimental rhegmatogenous retinal detachment was produced in a rabbit model after partial vitrectomy, followed by retinal tear formation.
RESULTS
Although 5'-Nase activity gradually decreased during the period of detachment, activity was still detectable after 24 weeks. G6P activity increased in the region of the detached neural retina. Around the border of the detached retina, the decrease in 5'-Nase activity extended approximately 140 micrometers into the adjacent attached retina at 2 weeks after detachment and 270 micrometers at 24 weeks.
CONCLUSIONS
These observations suggest that some anatomical and biochemical damages may occur in the retina adjacent to bullous retinal detachment and may explain the reduction in postoperative vision in some clinical cases.
Topics: 5'-Nucleotidase; Animals; Female; Glucose-6-Phosphatase; Histocytochemistry; Male; Rabbits; Retina; Retinal Detachment; Retinal Perforations; Vitrectomy
PubMed: 9043824
DOI: 10.1076/ceyr.16.1.56.5115