Cultivation of Limnospira maxima under extreme environmental conditions in Saudi Arabia: Salinity adaptation and scaling-up from laboratory culture to large-scale production.

Limnospira maxima has been adapted to grow in high salinity and in an economically alternative medium using industrial-grade fertilizers under harsh environmental conditions in Saudi Arabia. A sequence of scaling-up processes, from the laboratory to large-scale open raceways, was conducted along with gradual adaptation to environmental stress (salinity, light, temperature, pH). High biomass concentration at harvest point and areal productivity were achieved during the harsh summer season (1.122 g L-1 and 60.35 g m-2 day-1, respectively). The average protein content was found to be above 40 % of dry weight. Changes in the color and morphological appearance of the L. maxima culture were observed after direct exposure to sunlight in the outdoor raceways. These results demonstrate a successful and robust adaptation method for algal cultivation at outdoor large-scale in harsh environment (desert conditions) and also prove the feasibility of using hypersaline seawater (42 g kg-1) as an algal growth medium.

DAYWAKE implicates novel roles for circulating lipid-binding proteins as extracerebral regulators of daytime wake-sleep behavior.

Sleep during the midday, commonly referred to as siesta, is a common trait of animals that mainly sleep during the night. Work using Drosophila led to the identification of the daywake (dyw) gene, found to have anti-siesta activity. Herein, we show that the DYW protein undergoes signal peptide-dependent secretion, is present in the circulatory system, and accumulates in multiple organs, but, surprisingly, it is not detected in the brain where wake-sleep centers are located. The abundance of DYW in adult flies is regulated by age, sex, temperature, and the splicing efficiency of a nearby thermosensitive intron. We suggest that DYW regulates daytime wake-sleep balance in an indirect, extracerebral manner, via a multi-organ network that interfaces with the circulatory system.

Cultivation of the polyextremophile Cyanidioschyzon merolae 10D during summer conditions on the coast of the Red Sea and its adaptation to hypersaline sea water.

The west coast of the Arabian Peninsula borders the Red Sea, a water body which maintains high average temperatures and increased salinity compared to other seas or oceans. This geography has many resources which could be used to support algal biotechnology efforts in bio-resource circularity. However, summer conditions in this region may exceed the temperature tolerance of most currently cultivated microalgae. The Cyanidiophyceae are a class of polyextremophilic red algae that natively inhabit acidic hot springs. C. merolae 10D has recently emerged as an interesting model organism capable of high-cell density cultivation on pure CO2 with optimal growth at elevated temperatures and acidic pH. C. merolae biomass has an interesting macromolecular composition, is protein rich, and contains valuable bio-products like heat-stable phycocyanin, carotenoids, ß-glucan, and starch. Here, photobioreactors were used to model C. merolae 10D growth performance in simulated environmental conditions of the mid-Red Sea coast across four seasons, it was then grown at various scales outdoors in Thuwal, Saudi Arabia during the Summer of 2022. We show that C. merolae 10D is amenable to cultivation with industrial-grade nutrient and CO2 inputs outdoors in this location and that its biomass is relatively constant in biochemical composition across culture conditions. We also show the adaptation of C. merolae 10D to high salinity levels of those found in Red Sea waters and conducted further modeled cultivations in nutrient enriched local sea water. It was determined that salt-water adapted C. merolae 10D could be cultivated with reduced nutrient inputs in local conditions. The results presented here indicate this may be a promising alternative species for algal bioprocesses in outdoor conditions in extreme coastal desert summer environments.

Peripheral ulcerative keratitis as presenting manifestation of systemic microscopic polyangiitis: a case report / Ceratite ulcerativa periférica como manifestação de poliangiíte microscópica sistêmica: relato de caso

ABSTRACT Microscopic polyangiitis is a rare autoimmune disease of unknown etiology, characterized by inflammation and necrosis of blood vessels. It forms a part of the antineutrophil cytoplasmic antibody-associated vasculitides-a heterogeneous group of disorders characterized by vasculitis. It is a systemic disease affecting multiple organs. The patients may present with a wide variety of symptoms. Ocular manifestations may present as its initial clinical symptoms, necessitating a multidisciplinary approach for reducing the morbidity and mortality. Early diagnosis aids in the formulation of appropriate treatment and prevention of further complications. Aggressive treatment, including surgery, is often necessary to limit structural damage and preserve visual function. We present the case of an 82-year-old woman who initially presented with peripheral ulcerative keratitis that led to the diagnosis of microscopic polyangiitis.

RESUMO A poliangeíte microscópica é uma doença autoimune rara de etiologia desconhecida, caracterizada por inflamação e necrose dos vasos sanguíneos. Faz parte das vasculites associadas a anticorpos citoplasmáticos antineutrófilos - um grupo heterogêneo de doenças caracterizadas por vasculite. É uma doença sistêmica que afeta vários órgãos. Os pacientes podem apresentar uma grande variedade de sintomas. As manifestações oculares podem apresentar-se como seus sintomas clínicos iniciais, necessitando de abordagem multidisciplinar para redução da morbimortalidade. O diagnóstico precoce ajuda na formulação do tratamento adequado e na prevenção de complicações futuras. O tratamento agressivo, incluindo cirurgia, muitas vezes é necessário para limitar o dano estrutural e preservar a função visual. Apresentamos o caso de uma mulher de 82 anos que inicialmente apresentou ceratite ulcerativa periférica que levou ao diagnóstico de poliangite microscópica.

Atypical Syphilitic Outer Retinitis and Severe Retinal Vasculitis as Onset Manifestations in a Patient with Concurrent HIV and Syphilis Infection.

INTRODUCTION: The most distinctive patterns of posterior pole affectation in syphilitic patients are acute posterior placoid chorioretinitis (ASPPC), pseudoretinitis pigmentosa and panuveitis with white focal preretinal opacities. However, outer retinitis is not a common presenting feature in this disease. CASE REPORT: Thus, we report an atypical case of syphilitic outer retinitis (SOR) and severe retinal phlebitis as presenting manifestations in a patient with HIV and syphilis coinfection. We consider that this patient had mixed characteristics of SOR and ASPPC with features of acute zonal occult outer retinopathy (AZOOR) spectrum, which has only rarely been published in recent years. CONCLUSION: Prompt and appropriate antibiotic treatment permitted total restoration of the external retinal layers, resolution of retinal vasculitis and recuperation of visual acuity. Since SOR is treatable in contrast to AZOOR, ophthalmologists should be aware that SOR needs to be ruled out when making a diagnosis of AZOOR.

Peripheral ulcerative keratitis as presenting manifestation of systemic microscopic polyangiitis: a case report.

Microscopic polyangiitis is a rare autoimmune disease of unknown etiology, characterized by inflammation and necrosis of blood vessels. It forms a part of the antineutrophil cytoplasmic antibody-associated vasculitides-a heterogeneous group of disorders characterized by vasculitis. It is a systemic disease affecting multiple organs. The patients may present with a wide variety of symptoms. Ocular manifestations may present as its initial clinical symptoms, necessitating a multidisciplinary approach for reducing the morbidity and mortality. Early diagnosis aids in the formulation of appropriate treatment and prevention of further complications. Aggressive treatment, including surgery, is often necessary to limit structural damage and preserve visual function. We present the case of an 82-year-old woman who initially presented with peripheral ulcerative keratitis that led to the diagnosis of microscopic polyangiitis.

A novel method of screening combinations of angiostatics identifies bevacizumab and temsirolimus as synergistic inhibitors of glioma-induced angiogenesis.

Tumor angiogenesis is critical for the growth and progression of cancer. As such, angiostasis is a treatment modality for cancer with potential utility for multiple types of cancer and fewer side effects. However, clinical success of angiostatic monotherapies has been moderate, at best, causing angiostatic treatments to lose their early luster. Previous studies demonstrated compensatory mechanisms that drive tumor vascularization despite the use of angiostatic monotherapies, as well as the potential for combination angiostatic therapies to overcome these compensatory mechanisms. We screened clinically approved angiostatics to identify specific combinations that confer potent inhibition of tumor-induced angiogenesis. We used a novel modification of the ex ovo chick chorioallantoic membrane (CAM) model that combined confocal and automated analyses to quantify tumor angiogenesis induced by glioblastoma tumor onplants. This model is advantageous due to its low cost and moderate throughput capabilities, while maintaining complex in vivo cellular interactions that are difficult to replicate in vitro. After screening multiple combinations, we determined that glioblastoma-induced angiogenesis was significantly reduced using a combination of bevacizumab (Avastin®) and temsirolimus (Torisel®) at doses below those where neither monotherapy demonstrated activity. These preliminary results were verified extensively, with this combination therapy effective even at concentrations further reduced 10-fold with a CI value of 2.42E-5, demonstrating high levels of synergy. Thus, combining bevacizumab and temsirolimus has great potential to increase the efficacy of angiostatic therapy and lower required dosing for improved clinical success and reduced side effects in glioblastoma patients.

Corneal endothelial cell loss after trabeculectomy and phacoemulsification in one or two steps: a prospective study.

OBJECTIVE: The objective of this study was to analyse the results of the surgical treatment of coexisting cataract and glaucoma and its effects on corneal endothelial cell density (CECD). METHODS: We include two longitudinal prospective studies: one randomised that included 40 eyes with open angle glaucoma that received one- (n = 20) or two-step (n = 20) phacotrabeculectomy and another that included 20 eyes that received phacoemulsification. We assess the impact of surgery on different clinical variables and in particular in CECD using Confoscan 4™ confocal microscopy and semiautomatic counting methods. RESULTS: Phacoemulsification and phacotrabeculectomy, but not trabeculectomy, increase significantly best-corrected visual acuity and anterior chamber depth and trabeculectomy and one- or two-step phacotrabeculectomy decreased similarly the intraocular pressure. We document percentages of endothelial cell loss of 3.1%, 17.9%, 31.6% and 42.6% after trabeculectomy, phacoemulsification and one- or two-step phacotrabeculectomy, respectively. The coefficient of variation did not increase significantly after surgery but the percentage of hexagonality decreased significantly after phacoemulsification and after two-step phacotrabeculectomy. CONCLUSIONS: Trabeculectomy, phacoemulsification and phacotrabeculectomy are surgical techniques that cause morphological changes and decrease the densities of the corneal endothelial cells. Trabeculectomy produces lesser endothelial cell loss than phacoemulsification, and phacoemulsification lesser cell loss than phacotrabeculectomy. Two-step phacotrabeculectomy (trabeculectomy followed 3 months later by phacoemulsification) causes more cell loss than one-step phacotrabeculectomy, and this could be due to the cumulative effects of two separate surgical traumas or to a negative conditioning lesion effect of the first surgery. For the treatment of coexisting glaucoma and cataract, one-step phacotrabeculectomy is the treatment of choice.

Echocardiographic Characteristics of Subjects With COVID-19: A Case Series.

Although coronavirus disease 2019 (COVID-19) manifests in most cases with respiratory symptoms, other presentations can occur. Direct damage to the cardiovascular system has been reported and recently, acute myocardial injury has been identified as a risk factor for mortality. Transthoracic echocardiography is a non-invasive tool that allows the detection of myocardial damage with validated markers (left ventricular ejection fraction and global longitudinal strain). Herein, we present the echocardiographic findings in four patients with COVID-19. All cases had acute respiratory distress syndrome (100%). Three out of four had elevated levels of creatine kinase and creatine kinase myocardial band. One case had ventricular concentric remodeling (25%). All cases (100%) had altered ventricular function: two had a reduced ejection fraction (50%) and, of those available for global longitudinal strain analysis, all had abnormal global longitudinal strain (100%). One case was found to have a tricuspid vegetation of 12 × 10 mm with no other manifestation of endocarditis. All of our cases had left ventricular dysfunction as assessed by echocardiography. One of our patients had a vegetation in the tricuspid valve. Two of our cases had a reduced ejection fraction. The importance of acute cardiac injury in COVID-19 has recently been established. A recent study found it to be an independent risk factor for mortality in patients with this disease. Information regarding echocardiographic characteristics of this population is scarce. Further research to elucidate the impact of these characteristics on morbidity and mortality is urgently needed.

CHANGES IN CHORIOCAPILLARIS, SATTLER, AND HALLER LAYER THICKNESSES IN CENTRAL SEROUS CHORIORETINOPATHY AFTER HALF-FLUENCE PHOTODYNAMIC THERAPY.

PURPOSE: To determinate the variation in thickness of the individual choroidal layers in patients with central serous chorioretinopathy treated with half-fluence photodynamic therapy. METHODS: Twenty-two eyes were evaluated with spectral-domain optical coherence tomography. The images were taken before photodynamic therapy, 3 months, and 6 months after the treatment. Two investigators performed these measurements: 1) choroidal thickness (CT), 2) Haller layer thickness, defined as the most external layer containing a 100-µm vessel, and 3) choriocapillaris + Sattler layer (C&S). Nine measurements were taken in the macular region. RESULTS: Choroidal thickness before photodynamic therapy was 471.8 µm ± 145.8. The Haller layer was 358.4 µm ± 122.6, and C&S was 114.3 µm ± 27.8. At 3-month follow-up, CT was 441.1 µm ± 150.7, Haller layer 348.8 µm ± 127.6, and C&S 92.4 µm ± 27.9. At 6-month follow-up, CT was 420.4 µm ± 118.4, Haller layer 331.8 µm ± 97.2, and C&S 89.5 µm ± 28.0. Using a multilevel mixed-effects linear regression, CT was found to be reduced at both 3 months (P < 0.03) and at 6 months (P < 0.001), Haller layer showed no significant reduction at 3 months (P = 0.483) or at 6 months (P = 0.055), and C&S showed reduction at 3 months (P < 0.001) and at 6 months (P < 0.001). Fellow nonaffected eyes showed no statistical variation at 3-month and 6-month follow-up. CONCLUSION: Reduction in CT in patients affected by central serous chorioretinopathy after half-fluence photodynamic therapy occurs primarily in the choriocapillaris and medium diameter vessel layers of the choroid in a short- and medium-term follow-up.

VISUALIZATION OF CHOROIDAL NEOVASCULARIZATION USING TWO COMMERCIALLY AVAILABLE SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY DEVICES.

PURPOSE: To compare the sensitivity of detection and the measured size of choroidal neovascularization (CNV) on two commercially available spectral domain optical coherence tomography angiography (OCTA) devices, the Optovue RTVue XR Avanti with AngioVue and the Zeiss Cirrus HD-OCT with AngioPlex. METHODS: Patients with CNV lesions were imaged consecutively on both OCTA devices on the same day of their visit. 3 × 3 mm and 6 × 6 mm scans centered at the fovea were obtained. Two independent masked readers evaluated the OCTA images for CNV identification and its area measurements. RESULTS: No significant differences were observed between the 2 OCTA devices in CNV area measurements on their 3 × 3 mm and 6 × 6 mm scans. However, there was suboptimal performance of their automated segmentation algorithms as compared to manually adjusted segmentation for visualizing CNV lesions. CONCLUSION: There was no significant difference in the size of the CNV lesion as measured on either commercially available spectral domain OCTA device. Both devices were comparable in their detection of CNV lesions on manual adjustment of segmentation lines. However, their automated segmentation algorithms need improvement to allow for accurate measurement of CNV lesions for routine clinical application.

Utilization of centrate for the outdoor production of marine microalgae at the pilot-scale in raceway photobioreactors.

In this study, the outdoor production of marine microalgae in raceway photobioreactors was investigated, modifying the centrate percentage in the culture medium (20, 30, 40 and 50%) and using two different dilution rates (0.2 day-1 and 0.3 day-1). The data obtained showed that microalgae are capable of producing biomass in addition to recovering the nutrients contained in the centrate. The best results for biomass productivity and light efficiency were obtained when the centrate was set at 20% with a dilution rate of 0.3 day-1. The biomass productivity was 32.42 g m-2·day-1 while the photosynthetic efficiency was 0.74 gbiomass·E-1 (3.66%). Regarding the nutrients, nitrogen (the majority being in the form of ammonium [NH4+]) and phosphorus were only fixed into biomass when optimal conditions were set; if this was not the case, they were lost to stripping or precipitation. The maximal nutrient removal capacities under the optimal conditions were 28.72 mgN·l-1·day-1 and 3.99 mgP·l-1·day-1. Population changes were determined by the dilution rate set whilst the centrate percentage had little effect. Four strains were present in the culture, Nannochloropsis g. being the main one. Biochemical changes did not vary greatly between the conditions set for the culture, with a composition rich in proteins and carbohydrates being observed. One can conclude that to produce marine microalgal biomass for a range of potential commodities such as feed, biofertilizers and biofuels, it is possible to use centrate from anaerobic digestion as the sole nutrient source, as a way of reducing costs.

Anterior Chamber Angle and Trabecular Meshwork Measurements Made by Fourier-domain Optical Coherence Tomography in Healthy White Children.

PURPOSE: To obtain anterior chamber angle and trabecular meshwork (TM) measurements by Fourier-domain optical coherence tomography (FD-OCT) in a population of healthy white children. MATERIALS AND METHODS: This was a cross-sectional study examining 409 right eyes of 409 children. Trabecular-iris angle (TIA) and TM length and area were measured by FD-OCT (RTVue 100) in the nasal and temporal quadrants to analyze correlations between angle or TM measurements and age, sex, and refractive error. RESULTS: Mean participant age was 10.5±3.4 years (range, 3 to 18 y); 51% were boys. Mean spherical error was 0.56±2.4 D (range, -9 to +7.5 D). TIA could be measured in 99%, whereas TM measurements could only be made in 83%. Mean TIA was 43.1±10.0 degrees (range, 16 to 76 degrees). No differences were observed in angle width according to sex (P=0.299; t test). TIA was correlated with age (R=0.204; P<0.001) and with spherical error (R=-0.457; P<0.001). Mean TM length was 530±106 µm (range, 299 to 891 µm) and mean TM area was 0.065±0.021 mm (range, 0.030 to 0.180 mm). No correlation was observed between TM metrics and age, sex or refractive error (R<0.08; P≥0.172). CONCLUSIONS: FD-OCT proved useful for the noninvasive measurement of TIA and TM metrics in children. Spherical error was the main determinant of TIA.

Nanotubus de carbono y bionanotecnología / Carbon nanotubes and bionanotechnology

Los nanotubos de carbono (NTC) son estructuras artificiales novedosas que presentan propiedades físicas inusuales. Estas propiedades han hecho a los NTC objeto de una gran cantidad de estudios, los cuales han revelado un inmenso potencial de aplicación en diferentes áreas, tales como la electrónica, la física y la biología. En este trabajo se revisan los conceptos básicos sobre la química, obtención y modificación de los NTC, y se discute su posible utilización en sistemas biológicos.