Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Long-Term Favorable Visual Outcomes in Patients with Large Submacular Hemorrhage

Submacular hemorrhage (SMH) has been reported to be toxic to the retina based on animal studies. However, observational studies of patients with neovascular-related SMH and those treated with intravitreal anti-vascular growth factor (anti-VEGF) therapy have shown many favorable visual acuity outcomes. We report two cases of neovascular-related SMH with ten or more years of follow-up. The first case was an 83-year old female with a history of nonexudative age-related macular degeneration in both eyes presenting with sudden decrease in vision (20/400) in her right eye due to a large SMH, treated with anti-VEGF therapy. Over the next following months, there was resolution of the hemorrhage and return of good visual acuity. At 10-year follow-up, visual acuity was 20/30 in the right eye. The second case was a 49-year old female with a history of presumed ocular histoplasmosis syndrome (POHS), presenting with sudden vision loss (20/400) in her right eye due to large, thick SMH. With observation and intermittent anti-VEGF therapy, there was resolution of the hemorrhage. At 30-year follow-up, visual acuity was 20/20 in the right eye

Identification of macular neovascularization in central serous chorioretinopathy using swept-source OCT angiography

Purpose: Swept-source optical coherence tomography angiography (SS-OCTA) was used to detect the presence of macular neovascularization (MNV) in eyes with exudative central serous chorioretinopathy (CSCR). Observations: Case 1 is a 73-year-old man using prednisolone drops with 20/40 vision and a retinal pigment epithelial detachment (PED) associated with subretinal fluid (SRF) and no clinical signs of age-related macular degeneration (AMD) in his left eye. Three months after presentation he underwent SS-OCTA imaging that revealed MNV. He received a series of intravitreal anti-vascular endothelial growth factor (VEGF) injections and SS-OCTA imaging showed a decrease in the MNV lesion size with resolution of the SRF. VA improved to 20/25. Case 2 is a 65-year-old man with recent oral steroid use, presenting with 20/20 vision, a PED, SRF, and no evidence of AMD. SS-OCTA imaging at presentation revealed MNV, which worsened on interval SS-OCTA imaging after the patient deferred treatment. Intravitreal anti-VEGF therapy was then performed with resolution of the SRF and VA improved to 20/15. A total of six cases of type 1 MNV were diagnosed with CSCR. Most were men with a history of steroid or testosterone use and were treated with good response. Conclusions and importance: SS-OCTA imaging provides a convenient non-invasive strategy for identifying CSCR eyes with MNV without the need for dye-based angiography

Endophthalmitis Caused by Kocuria Kristinae

Kocuria is an anaerobic, Gram-positive bacterium, which has been rarely reported to cause endophthalmitis following cataract surgery, intravitreal injections, penetrating ocular trauma, and also secondary to endogenous sources. Visual prognosis is often guarded, with no previous cases reporting a final visual acuity better than 20/60. We describe a young female patient who developed culture-proven Kocuria kristinae endophthalmitis associated with a traumatic scleral rupture. Visual acuity at 2 months of follow-up improved from light perception to 20/50 after treatment with intravitreal antimicrobial therapy and pars plana vitrectomy

Endophthalmitis Prophylaxis

In this chapter, we discuss techniques in the prophylaxis of infection by inhibiting or arresting the growth and multiplication of germs (infectious agents) which is usually achieved by povidone-iodine, hydrogen peroxide, chlorhexidine, or polyhexanide application on the skin. We also discuss the settings in which topical antibiotics and intracameral antibiotics may be utilized