Characterization of anisotropic pore structure and dense selective layer of capillary membranes for long-term ECMO by cross-sectional ion-milling method.

Since the COVID-19 pandemic of 2020-2023, extracorporeal membrane oxygenator (ECMO) has attracted considerable attention worldwide. It is expected that ECMO with long-term durability is put into practical use in order to prepare for next emerging infectious diseases and to facilitate manufacturing for novel medical devices. Polypropylene (PP) and polymethylpentene (PMP) capillary membranes are currently the mainstream for gas exchange membrane for ECMO. ECMO support days for COVID-19-related acute hypoxemic respiratory failure have been reported to be on average for 14 or 24 days. It is necessary to improve opposing functions such that promoting the permeation of oxygen and carbon dioxide and inhibiting the permeation of water vapor or plasma to develop sufficient durability for long-term use. For this purpose, accurately controlling the anisotropy of the pore structure of the entire cross section and functions of capillary membrane is significant. In this study, we focused on the cross-sectional ion-milling (CSIM) method, to precisely clarify the pore structure of the entire cross section of capillary membrane for ECMO, because there is less physical stress on the porous structure applied during the preparation of cross-sectional samples of porous capillary membranes. We attempted to observe the cross sections of commercially available PMP membranes using the CSIM method. As a result, we succeeded in fabricating fine-scale flat cross-sectional samples of PMP capillary membranes. The pore structures and the degree of anisotropy of the cross sections are quantitatively clarified. The achievements and the approaches of this study are being applied to the development of next-generation gas exchange membranes.

Mean Platelet Volume Is Associated with Early Neurological Deterioration in Patients with Branch Atheromatous Disease: Involvement of Platelet Activation.

BACKGROUND: The most attentive clinical problem in patients with branch atheromatous disease (BAD) is early neurological deterioration (END). Although the platelet activation (PA) is involved in pathogenesis, the relationship between PA and END has remained unclear. We investigated clinical data including mean platelet volume (MPV, fL) as a marker for PA to identify clinically useful biomarkers for END. METHODS: A total of 64 patients with BAD were investigated retrospectively, and divided into 2 groups based on whether neurologic symptoms deteriorated or not: BAD with and without END (END and non-END). The END was defined as patients with point increase of 1 or greater in the National Institutes of Health Stroke Scale (NIHSS); non-END was defined as those without such increase. Clinical features such as NIHSS, modified Rankin scale (mRS), laboratory data including MPV, lesion size (LS, mm) on admission, and treatments were compared between the 2 groups. RESULTS: Of 64 patients, 17 cases had an END. The median values of NIHSS, mRS, MPV, and LS on admission were significantly greater in END than in non-END (P < .05, respectively). There was no correlation of MPV with NIHSS, mRS and LS, respectively. The median values of MPV were significantly higher in END than in non-END and control (P < .05, respectively). A receiver operating characteristic curve indicated a value of 10.1 as cutoff level for MPV to discriminate between END and non-END. CONCLUSIONS: High MPV values on admission may be an independent biomarker for END. Physicians should pay more careful attention to END in BAD showing MPV values higher than 10.1 on admission.

High-Efficiency Near-Infrared-to-Visible Photon Upconversion in Poly(vinyl alcohol) Porous Film.

Triplet-triplet annihilation photon upconversion (TTA-UC) has received significant attention in energy harvesting applications such as solar cells. The realization of high upconversion (UC) performance in the form of films is a crucial factor for the incorporation of this technology into large-area devices. Herein, we propose a porous UC film prepared by an emulsification method with a poly(vinyl alcohol) (PVA) aqueous solution and a toluene solution of chromophores (rubrene/Pd-tetraphenyltetraanthraporphyrin pair) that achieved considerable UC performance in the near-infrared (NIR) (810 nm) to visible (560 nm) range with a maximum quantum yield of 3.7% (out of 50%). Notably, the films displayed a UC emission when using an NIR light-emitting diode as a low-power-density noncoherent light source, which was confirmed by the naked eye. Excitation-power-dependent time-resolved photoluminescence measurements showed almost identical triplet lifetimes of emitter species for the films and toluene solutions; however, lower threshold intensities (Ith = 1-2 W/cm2) were observed for the films than those of the solutions (Ith = ∼10 W/cm2). An evaluation of the remaining toluene in the film and UC emission behavior in liquid nitrogen suggested that the chromophores exist as an amorphous solid in the pores, thus enabling hybrid triplet energy transfer (chromophore mobility based and exciton migration) in this unique film. The presented methodology can be generalized to other wavelengths and can enable diverse applications of the TTA-UC technology.

Comparison of central visual sensitivity between monocular and binocular testing in advanced glaucoma patients using imo perimetry.

BACKGROUND/AIM: This study aimed to compare central visual sensitivity under monocular and binocular conditions in patients with glaucoma using the new imo static perimetry. METHODS: Fifty-one consecutive eyes of 51 patients with open-angle glaucoma who were affected with at least one significant point in the central 10° were examined in this cross-sectional study. Monocular and binocular random single-eye tests were performed using the imo perimeter and the Humphrey field analyser (HFA) 24-2 and 10-2 tests. The eyes were assigned to 'better' and 'worse' categories based on the visual acuity and central visual thresholding. Central visual sensitivity results obtained by monocular, binocular random single-eye tests and binocular simultaneous both eye test were compared. RESULTS: The average mean deviation with the HFA 24-2 was -5.5 (-1.5, -14.6) dB (median, (IQR)) in the better eyes and -18.0 (-12.9, -23.8) dB in the worse eyes. The mean sensitivity in the central 4 points of the visual field (VF) of the worse eyes was lower when measured under the binocular eye condition than under the monocular condition. Conversely, this value of the better eyes was greater when measured under the binocular eye condition than under the monocular condition. CONCLUSIONS: The central sensitivity of the better eyes was better and that of the worse eyes poorer with binocular testing than with monocular testing in patients with glaucoma. Although monocular VF testing is still the most straightforward means to monocularly monitor glaucoma at clinical settings, binocular testing, such as provided with imo perimetry, may be a useful clinical tool to predict the effect of VF impairments on a patient's quality of visual life.

Genetic diversity in Rhizopus oryzae strains as revealed by the sequence of lactate dehydrogenase genes.

Twenty-seven strains of Rhizopus oryzae accumulating predominantly lactic acid were shown to possess two ldh genes, ldhA and ldhB, encoding NAD-dependent lactate dehydrogenases. Variation in nucleotide sequence was identified for each gene from different strains, and similar phylogenetic trees were obtained based on the nucleotide sequences of both genes. The other 21 strains of R. oryzae accumulating predominantly fumaric and malic acids contained a single ORF of ldhB. Compared to the strains accumulating predominantly lactic acid, a lower degree of sequence divergence was found in ldhB, resulting in a separate cluster in the phylogenetic tree. The high similarity (>90%) spanning the ORF and adjacent regions demonstrates that ldhA and ldhB are derived from the same ancestor gene. The strains accumulating predominantly fumaric and malic acids lack functional ldhA, which plays a role in lactic acid synthesis and may form a lineage separated from the strains accumulating predominantly lactic acid in the genus Rhizopus.