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1.
J Acoust Soc Am ; 156(3): 1529-1542, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-39235272

ABSTRACT

Relative humidity, temperature, and wind along flight paths from a 10-year simulation are used to investigate the effects of the atmospheric conditions on sonic boom loudness generated by the pseudo-Concorde and a low-boom supersonic aircraft using an acoustic wave propagation tool. Global meteorological conditions are simulated using the chemistry-climate model EMAC with ECMWF reanalysis data. The results show that atmospheric conditions lead to a seasonal variation of the perceived level for a N-wave over 10 years of flights, whereas it is difficult to identify the seasonal variation for the low-boom aircraft because the distribution of perceived levels is widely spread. The dominant effect from atmospheric conditions during acoustic propagation is found for the low-boom aircraft cruising at an altitude of 14.478 km. The molecular relaxation effect is dominant for an overpressure reduction at 10 km but does not impact the pressure waveform below 8 km. At altitudes below 8 km, the thermoviscous absorption exclusively influences the variations in pressure rise time. Moreover, acoustic wave propagation through the turbulent field was simulated at a single location. Even though the acoustic wave passed through the same turbulent field in the summer and winter cases, the loudness on the ground differs between them.

2.
Genome Biol Evol ; 16(9)2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39240721

ABSTRACT

Zoantharia is an order among the Hexacorallia (Anthozoa: Cnidaria), and includes at least 300 species. Previously reported genomes from scleractinian corals and actiniarian sea anemones have illuminated part of the hexacorallian diversification. However, little is known about zoantharian genomes and the early evolution of hexacorals. To explore genome evolution in this group of hexacorals, here, we report de novo genome assemblies of the zoantharians Palythoa mizigama (Pmiz) and Palythoa umbrosa (Pumb), both of which are members of the family Sphenopidae, and uniquely live in comparatively dark coral reef caves without symbiotic Symbiodiniaceae dinoflagellates. Draft genomes generated from ultra-low input PacBio sequencing totaled 373 and 319 Mbp for Pmiz and Pumb, respectively. Protein-coding genes were predicted in each genome, totaling 30,394 in Pmiz and 24,800 in Pumb, with each set having ∼93% BUSCO completeness. Comparative genomic analyses identified 3,036 conserved gene families, which were found in all analyzed hexacoral genomes. Some of the genes related to toxins, chitin degradation, and prostaglandin biosynthesis were expanded in these two Palythoa genomes and many of which aligned tandemly. Extensive gene family loss was not detected in the Palythoa lineage and five of ten putatively lost gene families likely had neuronal function, suggesting biased gene loss in Palythoa. In conclusion, our comparative analyses demonstrate evolutionary conservation of gene families in the Palythoa lineage from the common ancestor of hexacorals. Restricted loss of gene families may imply that lost neuronal functions were effective for environmental adaptation in these two Palythoa species.


Subject(s)
Anthozoa , Multigene Family , Animals , Anthozoa/genetics , Genome , Phylogeny , Evolution, Molecular , Neurons/metabolism
3.
Angew Chem Int Ed Engl ; : e202412808, 2024 Aug 22.
Article in English | MEDLINE | ID: mdl-39175330

ABSTRACT

A highly selective cross-coupling reaction between Si-OAc (AcO = acetoxy) and Si-OH compounds that generates unsymmetrical and symmetrical oligosiloxanes concurrent with the release of acetic acid has been developed. The high selectivity arises from the reactivity difference that depends on the varying number of acetoxy groups present, thus facilitating a clean one-pot synthesis of oligosiloxanes. For instance, the reactions of di-, tri-, or tetraacetoxysilanes with silanols furnish acetoxy-containing di- and trisiloxanes in high yield. Two equivalents of tetraacetoxysilane can react with various silanediols to form 1,1,1,3,3,3-hexaacetoxytrisiloxanes, which subsequently react with a second molecule of a silanediol to selectively afford 1,1,3,3-tetraacetoxycyclotetrasiloxanes. The cyclotetrasiloxanes further react with a third molecule of silanediol to provide unprecedented bicyclic pentasiloxanes with acetoxy groups at the bridgehead silicon atoms. Applications of the acetoxy-containing products as efficient surface-treatment agents and new building blocks for highly heat-resistant materials are demonstrated.

4.
Clin Exp Nephrol ; 2024 Aug 22.
Article in English | MEDLINE | ID: mdl-39168885

ABSTRACT

BACKGROUND: Aortic stenosis (AS) and aortic valve calcification (AVC) are occasionally observed in patients receiving maintenance dialysis. However, their prevalence and factors associated with them in patients undergoing dialysis remain unknown. We aimed to elucidate the aortic valve status at the time of dialysis initiation and patient prognosis based on aortic valve status. METHODS: We analyzed 289 patients initiating dialysis (hemodialysis: peritoneal dialysis = 275:14) between 2016 and 2023. "AS and/or AVC" was detected using echocardiography. AS was defined as a maximum transaortic velocity > 2.0 m/s. Statistical analyses including multivariable logistic regression and Cox regression were used to assess the association between patient characteristics and survival outcomes. RESULTS: Aortic valve changes were observed in 121 (42%) patients, among which 33 (11%) met the AS criteria. The mean age of patients in the AS, AVC without AS, and control groups was 79.1 ± 8.9, 75.9 ± 9.2, and 68.3 ± 12.9, respectively (P < 0.001). Multivariable logistic regression models showed that only age was associated with aortic valve changes (P < 0.001). Age and other important factor-adjusted multivariable Cox regression models showed that AS was an independent risk factor for death after dialysis initiation (hazard ratio (HR): 1.95, 95% confidence interval (CI): 1.06 - 3.59, P = 0.04). However, aortic valve changes ("AS and/or AVC") were not a risk factor for death (HR: 1.51, 95% CI 0.95 - 2.39, P = 0.08). CONCLUSIONS: With the growing older population undergoing dialysis, aortic valve changes should be closely monitored. Particularly, AS is crucial because of its impact on patient prognosis.

5.
Ther Apher Dial ; 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38946143

ABSTRACT

INTRODUCTION: Functional decline occurs during dialysis initiation, particularly in unplanned cases. To prevent unplanned hemodialysis, we aimed to identify associated factors from the first referral to the nephrology department to hemodialysis initiation and assess patient prognosis post-unplanned hemodialysis initiation. METHODS: This retrospective study involved 257 Japanese patients initiating hemodialysis and compared patient characteristics based on whether hemodialysis was planned or unplanned at a single center. Patient outcomes were evaluated in collaboration with maintenance hemodialysis centers. RESULTS: Unplanned hemodialysis initiation correlated with heart failure history (p < 0.05) and infections like pneumonia (p < 0.001). Patients with unplanned hemodialysis initiation had a worse prognosis than those with planned initiation (p < 0.001), and multivariable Cox regression showed it as an independent risk factor for death (p < 0.05). CONCLUSIONS: Hygiene and careful attention to heart failure may reduce unplanned hemodialysis and improve patient well-being and healthcare efficiency. This retrospective analysis highlights crucial considerations for optimizing the initiation of hemodialysis.

6.
Allergol Immunopathol (Madr) ; 52(4): 97-103, 2024.
Article in English | MEDLINE | ID: mdl-38970272

ABSTRACT

INTRODUCTION AND OBJECTIVES: Macrophage-induced inflammation plays a key role in defense against injury and harmful pathogens. Autophagy and the inflammatory response are associated; however, the relationship between the autophagy pathway and lipopolysaccharide (LPS)- induced inflammatory responses remains unknown. We aimed to determine the effect of autophagy on the LPS-induced myeloid differentiation factor 88 (MyD88)/nuclear transcription factor kB (NF-kB) pathway-mediated inflammatory response in RAW264.7 cells. MATERIALS AND METHODS: To determine the effect of autophagy on the LPS-induced inflammatory response, using various in vitro assays, we determined the effect of autophagy inhibitors and inducers on the inflammatory response in RAW264.7 cells. RESULTS: Chloroquine (CQ), an autophagy inhibitor, suppressed pro-inflammatory cytokines, including interleukin (IL)-1ß, IL-6, and tumor necrosis factor α (TNFα) in LPS-stimulated RAW264.7 cells. CQ also affected inflammatory mediators such as myeloid differentiation factor 88 and NF-kB in LPS-stimulated RAW264.7 cells. CONCLUSION: This study demonstrated that CQ regulates the LPS-induced inflammatory response in RAW264.7 cells. We propose that targeting the regulation of pro-inflammatory cytokine levels and inflammatory mediators using CQ is a promising therapeutic approach for preventing inflammatory injury. CQ serves as a potential therapeutic target for treating various inflammatory diseases.


Subject(s)
Chloroquine , Cytokines , Lipopolysaccharides , Macrophages , Myeloid Differentiation Factor 88 , NF-kappa B , Animals , Mice , Chloroquine/pharmacology , RAW 264.7 Cells , NF-kappa B/metabolism , Macrophages/drug effects , Macrophages/immunology , Macrophages/metabolism , Cytokines/metabolism , Myeloid Differentiation Factor 88/metabolism , Autophagy/drug effects , Autophagy/immunology , Inflammation/immunology , Inflammation/drug therapy , Signal Transduction/drug effects , Anti-Inflammatory Agents/pharmacology , Inflammation Mediators/metabolism
7.
Radiol Case Rep ; 19(8): 3429-3433, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38872746

ABSTRACT

Retroperitoneal leiomyosarcoma (RPLMS) is rare and usually presents as a large abdominal mass with poor clinical symptoms. Radiological findings of an RPLMS arising in the pelvis of a woman resemble those of adnexal tumors. Herein, we present a case of RPLMS mimicking an adnexal tumor which was differentiated from having an ovarian origin as the right ovarian vein was passing through the tumor but there was no direct vascular connection with the tumor. Therefore, it is important to identify the ovarian vein to distinguish between these tumors.

8.
CEN Case Rep ; 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38902495

ABSTRACT

We present a case of an angioimmunoblastic T-cell lymphoma (AITL) and tubulointerstitial nephritis with storiform fibrosis in a 76-year-old man. The patient exhibited lymphadenopathy, polyclonal hypergammaglobulinemia, and renal dysfunction and was diagnosed with AITL on the basis of lymph node biopsy findings. The serum IgG4 level was highly elevated. Renal biopsy revealed IgG4-positive plasma cells and storiform fibrosis without infiltration of AITL, and the findings indicated IgG4-related kidney disease (IgG4-RKD). Following THPCOP therapy for AITL, the renal function improved. While diagnosing IgG4-RKD in a patient with AITL poses challenges, follicular helper T cell involvement appeared crucial in AITL and renal tubulointerstitial lesions in this case.

9.
Cureus ; 16(5): e61076, 2024 May.
Article in English | MEDLINE | ID: mdl-38915962

ABSTRACT

Addressing iron deficiency is the key to managing anemia in patients with chronic kidney disease (CKD). Erythropoiesis-stimulating agents (ESAs) and hypoxia-inducible factor prolyl-hydroxylase inhibitors (HIF-PHIs) are being prescribed to an increasing number of patients with CKD by primary physicians following the emergence of newer agents for the management of renal anemia. Among the 361 (average age: 76.8±12.1 years; 54.0% males) patients with stages 4 and 5 CKD newly referred to the nephrology department of our hospital between 2018 and 2023 who had evaluable transferrin saturation (TSAT) and ferritin levels, 169 patients (47%) had iron deficiency (ferritin <100 ng/mL or ferritin 100-300 ng/mL with TSAT <20%). The estimated glomerular filtration rate (eGFR), hemoglobin level, TSAT, and median ferritin level were 17.0±7.0 mL/min/1.73 m², 10.8±2.1 g/dL, 27.5±13.1%, and 130 ng/mL, respectively. ESAs, HIF-PHIs, and iron supplements were prescribed to 35 (9.7%), 17 (4.7%), and 35 (9.4%) patients, respectively. No significant differences were observed between the iron indices of the ESA group; however, the serum ferritin levels in the HIF-PHIs group were significantly lower than in those in the no-medication group (P=0.02). Multivariable logistic regression analysis revealed that age, female sex, eGFR, medications for renal anemia, and a history of ischemic heart disease were associated with iron deficiency (P<0.05). Although patients with renal failure tend to exhibit anemia, attention should be paid to iron deficiency anemia in addition to renal anemia, especially in patients with renal failure and a history of ischemic heart disease.

10.
Gynecol Oncol Rep ; 53: 101405, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38757116

ABSTRACT

Objective: Although cervical conization is considered a standard treatment for cervical intraepithelial neoplasia (CIN) 2/3, laser ablation can compensate for the disadvantages of the former. CO2, semiconductor, and holmium yttrium-aluminum-garnet (Ho:YAG) lasers are applied in ablation, but no previous studies have shown the effectiveness of any of these techniques. Here, we retrospectively analyzed the application of the Ho:YAG laser in our hospital to verify its efficacy, and discussed the methods for optimal recurrence detection. Methods: We evaluated the recurrence rates of the pathological condition in patients who underwent laser ablation with a Ho:YAG laser for CIN2/3 at our institution from June 2012 to November 2021. We defined the recurrence as histologically confirmed CIN2 or more advanced stage. Age, preoperative diagnosis, human papillomavirus (HPV) genotype, and postoperative high-risk HPV status were recorded to establish their association with recurrence rates. Results: We performed surgery in 607 patients and the 2-year recurrence rate after interventions was 5.6%. Five patients were diagnosed with invasive cancer at the time of recurrence. Older age significantly correlated with higher risk of recurrence, but preoperative CIN grade and preoperative HPV 16/18 status did not significantly affect it. The postoperative high-risk HPV test was 100% sensitive for detecting recurrence. Conclusions: Laser ablation with the Ho:YAG laser yields promising results. Together with postinterventional management, high-risk HPV test after laser ablation should be conducted after diagnostic conization.This study received the approval from the Ethics Committee of the NHO Tokyo Medical Center (Ethics Committee approval number: R22-067).

11.
CEN Case Rep ; 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38658458

ABSTRACT

A 62-year-old female patient with essential thrombocythemia experienced rapid renal dysfunction and was subsequently referred to our hospital. Further investigations did not reveal any significant abnormalities except for a slight increase in urinary ß2-microglobulin levels. A renal biopsy was performed to investigate the cause of her renal dysfunction, revealing acute tubular necrosis, interstitial edema, and arteriosclerosis. No significant glomerular lesions were observed. Immunofluorescence staining and electron microscopy showed no abnormalities. She had been using anagrelide for 4 years, and her dosage was increased from 2.0 to 3.0 mg/day 10 months before her initial admission. Her renal function began to deteriorate 2 months after the anagrelide dosage increase. Although 0.625 mg of bisoprolol was initiated for tachycardia 3 months after the anagrelide dosage adjustment, we suspected that the acute tubular necrosis was associated with anagrelide administration. After transitioning from anagrelide to hydroxyurea and discontinuing bisoprolol, her renal function improved. This case suggests the importance of considering anagrelide as a potential cause of renal dysfunction in patients using this medication. Therefore, renal biopsy, combined with a comprehensive medical history, is crucial for evaluating the etiology of renal injury in such cases.

12.
Surg Case Rep ; 10(1): 80, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38584215

ABSTRACT

BACKGROUND: Pancreaticoduodenal artery aneurysm (PDAA) is a rare, but fatal disease. However, the association between aneurysm size and the risk of rupture remains unclear. There are many options for therapeutic strategies that should be discussed well because the treatment options are often complicated and highly invasive. However, it remains unclear whether additional endovascular therapy is essential for all patients undergoing bypass surgery. Here, we present a case of triple PDAAs with celiac axis occlusion and spontaneous complete regression of inferior PDAAs (IPDAA) after aneurysmectomy of superior PDAA (SPDAA) and aorto-splenic bypass. CASE PRESENTATION: A 68-year-old woman presented with one SPDAA and two IPDAAs caused by celiac axis occlusion. Aneurysmectomy for IPDAAs was difficult because of their anatomical location and shape. Therefore, we planned a two-stage hybrid therapy. The patient underwent aorto-splenic bypass and resection of the SPDAA. Follow-up CT was performed to evaluate the IPDAAs before planned endovascular embolization. Spontaneous regression of the IPDAAs and normalized PDA arcade decreased the blood flow in the PDA arcade. The patient is doing well without graft occlusion, and the IPDAAs have completely regressed 7 years after surgery. CONCLUSION: Normalization of hyperinflow to the PDA arcade can lead to the regression of PDAA. Potentially, additional endovascular therapy may not be required in all cases when dilation of the PDA improves. However, more cases must be accumulated to establish criteria for predicting the risks of short- and long-term PDAA ruptures.

13.
Mar Biotechnol (NY) ; 26(2): 223-229, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38345665

ABSTRACT

Reef-building corals are a fundamental pillar of coral reef ecosystems in tropical and subtropical shallow environments. Corals harbor symbiotic dinoflagellates belonging to the family Symbiodiniaceae, commonly known as zooxanthellae. Extensive research has been conducted on this symbiotic relationship, yet the fundamental information about the distribution and localization of Symbiodiniaceae cells in corals is still limited. This information is crucial to understanding the mechanism underlying the metabolite exchange between corals and their algal symbionts, as well as the metabolic flow within holobionts. To examine the distribution of Symbiodiniaceae cells within corals, in this study, we used fluorescence imaging and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MS-Imaging) on branches of the Acropora tenuis coral. We successfully prepared frozen sections of the coral for molecular imaging without fixing or decalcifying the coral branches. By combining the results of MS-Imaging with that of the fluorescence imaging, we determined that the algal Symbiodiniaceae symbionts were not only localized in the tentacle and surface region of the coral branches but also inhabited the in inner parts. Therefore, the molecular imaging technique used in this study could be valuable to further investigate the molecular dynamics between corals and their symbionts.


Subject(s)
Anthozoa , Dinoflagellida , Microalgae , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Symbiosis , Anthozoa/metabolism , Animals , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Microalgae/metabolism , Coral Reefs , Molecular Imaging/methods
15.
Auris Nasus Larynx ; 51(2): 401-405, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37666746

ABSTRACT

OBJECTIVE: In the present study, we examined the effects of high-dose betahistine on dizziness handicap inventory (DHI) scores in patients with unilateral vestibulopathy. METHODS: An uncontrolled, open-label, multicenter clinical trial was conducted. Fifteen patients with unilateral vestibulopathy, such as vestibular neuritis, who complained of intractable dizziness for more than three months were enrolled. Initially, all patients were orally administered betahistine at a dose of 36 mg/day for four weeks, which is the standard dose and dosing period for the treatment of dizziness in Japan. The patients were then administered betahistine at a double dose of 72 mg/day for four weeks. Six patients who became aware of the benefits of high-dose betahistine were further administered betahistine at 72 mg/day for an additional 12 weeks (a total of 16 weeks). Perceived disability due to dizziness was assessed by DHI scores. RESULTS: In all 15 patients, short-term administration with high-dose (72 mg/day) betahistine for four weeks, but not low-dose betahistine (36 mg/day) for four weeks significantly decreased DHI scores. In particular, in six responding patients with self-reported benefits after short-term administration with high-dose betahistine, long-term administration with high-dose betahistine for 16 weeks further significantly decreased DHI scores. However, DHI scores of the remaining nine non-responding patients were not changed after short-term administration with high-dose betahistine for four weeks. CONCLUSION: Short-term administration with the standard dose and dosing period of betahistine did not improve DHI scores in the enrolled patients, indicating that they were not compensated for unilateral vestibulopathy with intractable dizziness. The present findings suggest that long-term administration with high-dose betahistine facilitates vestibular compensation to improve intractable dizziness in some, but not all patients with uncompensated unilateral vestibulopathy.


Subject(s)
Vestibular Neuronitis , Vestibule, Labyrinth , Humans , Betahistine/therapeutic use , Dizziness/drug therapy , Vertigo/drug therapy , Vestibular Neuronitis/complications , Vestibular Neuronitis/drug therapy
16.
Zoolog Sci ; 40(6): 444-454, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38064371

ABSTRACT

Coral-dinoflagellate symbiosis is a unique biological phenomenon, in which animal cells engulf single-celled photosynthetic algae and maintain them in their cytoplasm mutualistically. Studies are needed to reveal the complex mechanisms involved in symbiotic processes, but it is difficult to answer these questions using intact corals. To tackle these issues, our previous studies established an in vitro system of symbiosis between cells of the scleractinian coral Acropora tenuis and the dinoflagellate Breviolum minutum, and showed that corals direct phagocytosis, while algae are likely engulfed by coral cells passively. Several genera of the family Symbiodiniaceae can establish symbioses with corals, but the symbiotic ratio differs depending on the dinoflagellate clades involved. To understand possible causes of these differences, this study examined whether cultured coral cells show phagocytotic activity with various dinoflagellate strains similar to those shown by intact A. tenuis. We found that (a) A. tenuis larvae incorporate Symbiodinium and Breviolum, but not Cladocopium, and very few Effrenium, (b) cultured coral cells engulfed all four species but the ratio of engulfment was significantly higher with Symbiodinium and Breviolum than Cladocopium and Effrenium, (c) cultured coral cells also phagocytosed inorganic latex beads differently than they do dinoflagellates . It is likely that cultured coral cells preferentially phagocytose Symbiodinium and Breviolum, suggesting that specific molecular mechanisms involved in initiation of symbiosis should be investigated in the future.


Subject(s)
Anthozoa , Dinoflagellida , Animals , Phagocytosis , Symbiosis , Larva
17.
Brain Commun ; 5(6): fcad281, 2023.
Article in English | MEDLINE | ID: mdl-37953842

ABSTRACT

Pontine autosomal dominant microangiopathy and leukoencephalopathy is one of hereditary cerebral small vessel diseases caused by pathogenic variants in COL4A1 3'UTR and characterized by multiple small infarctions in the pons. We attempted to establish radiological features of this disease. We performed whole exome sequencing and Sanger sequencing in one family with undetermined familial small vessel disease, followed by clinicoradiological assessment and a postmortem examination. We subsequently investigated clinicoradiological features of patients in a juvenile cerebral vessel disease cohort and searched for radiological features similar to those found in the aforementioned family. Sanger sequencing was performed in selected cohort patients in order to detect variants in the same gene. An identical variant in the COL4A1 3'UTR was observed in two patients with familial small vessel disease and the two selected patients, thereby confirming the pontine autosomal dominant microangiopathy and leukoencephalopathy diagnosis. Furthermore, postmortem examination showed that the distribution of thickened media tunica and hyalinized vessels was different from that in lacunar infarctions. The appearance of characteristic multiple oval small infarctions in the pons, which resemble raisin bread, enable us to make a diagnosis of pontine autosomal dominant microangiopathy and leukoencephalopathy. This feature, for which we coined the name 'raisin bread sign', was also correlated to the pathological changes.

18.
Commun Biol ; 6(1): 1027, 2023 10 18.
Article in English | MEDLINE | ID: mdl-37853100

ABSTRACT

Due to the ecological importance of mutualism between reef-building corals and symbiotic algae (Family Symbiodiniaceae), various transcriptomic studies on coral-algal symbiosis have been performed; however, molecular mechanisms, especially genes essential to initiate and maintain these symbioses remain unknown. We investigated transcriptomic responses of Acropora tenuis to inoculation with the native algal symbiont, Symbiodinium microadriaticum, during early life stages, and identified possible symbiosis-related genes. Genes involved in immune regulation, protection against oxidative stress, and metabolic interactions between partners are particularly important for symbiosis during Acropora early life stages. In addition, molecular phylogenetic analysis revealed that some possible symbiosis-related genes originated by gene duplication in the Acropora lineage, suggesting that gene duplication may have been the driving force to establish stable mutualism in Acropora, and that symbiotic molecular mechanisms may vary among coral lineages.


Subject(s)
Anthozoa , Symbiosis , Animals , Symbiosis/genetics , Phylogeny , Anthozoa/genetics , Transcriptome , Gene Expression Profiling
19.
PLoS Comput Biol ; 19(9): e1011452, 2023 09.
Article in English | MEDLINE | ID: mdl-37683012

ABSTRACT

The cerebral arterial network covering the brain cortex has multiscale anastomosis structures with sparse intermediate anastomoses (O[102] µm in diameter) and dense pial networks (O[101] µm in diameter). Recent studies indicate that collateral blood supply by cerebral arterial anastomoses has an essential role in the prognosis of acute ischemic stroke caused by large vessel occlusion. However, the physiological importance of these multiscale morphological properties-and especially of intermediate anastomoses-is poorly understood because of innate structural complexities. In this study, a computational model of multiscale anastomoses in whole-brain-scale cerebral arterial networks was developed and used to evaluate collateral blood supply by anastomoses during middle cerebral artery occlusion. Morphologically validated cerebral arterial networks were constructed by combining medical imaging data and mathematical modeling. Sparse intermediate anastomoses were assigned between adjacent main arterial branches; the pial arterial network was modeled as a dense network structure. Blood flow distributions in the arterial network during middle cerebral artery occlusion simulations were computed. Collateral blood supply by intermediate anastomoses increased sharply with increasing numbers of anastomoses and provided one-order-higher flow recoveries to the occluded region (15%-30%) compared with simulations using a pial network only, even with a small number of intermediate anastomoses (≤10). These findings demonstrate the importance of sparse intermediate anastomoses, which are generally considered redundant structures in cerebral infarction, and provide insights into the physiological significance of the multiscale properties of arterial anastomoses.


Subject(s)
Ischemic Stroke , Humans , Infarction, Middle Cerebral Artery , Arteries , Brain , Computer Simulation
20.
PeerJ ; 11: e15562, 2023.
Article in English | MEDLINE | ID: mdl-37701833

ABSTRACT

Background: Aminoglycoside antibiotics are used for treating certain acute infections. However, these drugs cause ototoxicity by inducing inner ear hair cell death. Aims/Objectives: We investigated the protective effect of a nanoemulsion of the carotenoid astaxanthin on mammalian inner ear hair cells against neomycin-induced ototoxicity. Material and Methods: Dose-response relationship, quantification of hair cell loss, and reactive oxygen species production were assayed in response to neomycin with and without astaxanthin in cultured utricles of CBA/N mice. In addition, auditory brain response (ABR) and hair cell loss after exposure to the nanoformulation and loud noise were examined in vivo in guinea pigs. Results: Astaxanthin suppressed neomycin-induced reduction of hair cells by reducing the production of hydroxy radicals. Furthermore, hair cell loss in the second rotation of the cochlea was significantly lower in the astaxanthin group than in the noise-only group. Conclusions and Significance: The blood-labyrinth barrier limits the successful delivery of drugs for inner ear complications. However, in the nanoemulsion form, astaxanthin can penetrate the round window (fenestra ovale) membrane, enabling topical administration. Thus, astaxanthin nanoemulsion could be useful in treating ototoxicity in individuals with inner ear complications.


Subject(s)
Ear, Inner , Ototoxicity , Mice , Animals , Guinea Pigs , Mice, Inbred CBA , Neomycin , Alopecia , Mammals
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