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1.
World Neurosurg X ; 23: 100381, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38706708

RESUMO

Objective: To investigate on three-dimensional (3D) fusion images the apposition of low-profile visualized intraluminal support (LVIS) stents in intracranial aneurysms after treatment and assess inter-rater reliability. Materials and methods: Records of all patients with unruptured intracranial aneurysms who were treated with the LVIS stent were retrospectively accessed and included in this study. Two neurosurgeons evaluated the presence of malapposition between the vessel walls and the stent trunk (crescent sign) and the vessel wall and the stent edges (edge malappostion) on 3D fusion images. These images were high-resolution cone-beam computed tomography images of the LVIS stent fused with 3D-digital subtraction angiography images of the vessels. Associations between malapposition and aneurysm location were assessed by Fisher's exact test, and inter-rater agreement was estimated using Cohen's kappa statistic. Results: Forty consecutive patients were included. In all patients, 3D fusion imaging successfully visualized the tantalum helical strands and the closed-cell structure of the nitinol material of the low-profile visualized intraluminal support. A crescent sign was observed in 27.5 % and edge malapposition in 47.5 % of the patients. Malapposition was not significantly associated with location (p = 0.23 crescent sign, p = 0.07 edge malapposition). Almost perfect (κ = 0.88) and substantial (κ = 0.76) agreements between the two raters were found for the detection of crescent signs and edge appositions, respectively. Conclusions: 3D fusion imaging provided clear visualization of the LVIS stent and parent arteries, and could detect malapposition with excellent inter-rater reliability. This technique may provide valuable guidance for surgeons in determining postoperative management.

2.
Nat Nanotechnol ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627470

RESUMO

A sustainable society requires high-energy storage devices characterized by lightness, compactness, a long life and superior safety, surpassing current battery and supercapacitor technologies. Single-walled carbon nanotubes (SWCNTs), which typically exhibit great toughness, have emerged as promising candidates for innovative energy storage solutions. Here we produced SWCNT ropes wrapped in thermoplastic polyurethane elastomers, and demonstrated experimentally that a twisted rope composed of these SWCNTs possesses the remarkable ability to reversibly store nanomechanical energy. Notably, the gravimetric energy density of these twisted ropes reaches up to 2.1 MJ kg-1, exceeding the energy storage capacity of mechanical steel springs by over four orders of magnitude and surpassing advanced lithium-ion batteries by a factor of three. In contrast to chemical and electrochemical energy carriers, the nanomechanical energy stored in a twisted SWCNT rope is safe even in hostile environments. This energy does not deplete over time and is accessible at temperatures ranging from -60 to +100 °C.

3.
No Shinkei Geka ; 52(2): 263-269, 2024 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-38514115

RESUMO

With the advent of high-resolution imaging and advancements in computational fluid dynamics(CFD)and computational structural mechanics(CSM)analyses, clinical simulation of endovascular intervention has gradually become feasible. Virtual stents have become indispensable for coil embolization. For braided stents, such as those with low-profile visualized intraluminal support and flow diverters, predicting postplacement elongation and contraction is challenging; however, software development has enabled more precise treatment planning. Additionally, simulations utilizing three-dimensional(3D)printer models can enable realistic simulations of procedures such as intracranial stents and Woven EndoBridge placement. This approach is beneficial for shunt disorders such as arteriovenous malformations and dural arteriovenous fistulas, offering 3D visualization of shunt access routes and intuitive treatment strategy planning, even for beginners. Furthermore, it can be applied to procedures such as open surgical clipping and nidus resection, aiding in the selection of suitable clips and considerations for ideal resection based on nidus curvature. Simulations using CFD, CSM, and 3D printers are crucial for training surgeons and handling new devices. Harnessing medicine-engineering synergy is essential, and regulatory approval(insurance coverage)and appropriate commercialization of simulations are paramount for the future.


Assuntos
Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/cirurgia , Prótese Vascular , Stents , Software , Embolização Terapêutica/métodos , Resultado do Tratamento
4.
Front Neurol ; 15: 1343137, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38299017

RESUMO

Introduction: Intraprocedural rupture (IPR) is a serious complication of endovascular coil embolization of unruptured intracranial aneurysms (UIAs). Although outcomes after IPR are poor, methods to prevent subsequent neurological deterioration have not yet been investigated. We evaluated the risk factors and management strategies for IPR, particularly the role of balloon guiding catheters (BGCs) in rapid hemostasis. Methods: We retrospectively reviewed all UIA cases treated with coil embolization at three institutions between 2003 and 2021, focusing on preoperative radiological data, operative details, and outcomes. Results: In total, 2,172 aneurysms were treated in 2026 patients. Of these, 19 aneurysms in 19 patients (0.8%) ruptured during the procedure. Multivariate analysis revealed that aneurysms with a bleb (OR: 3.03, 95% CI: 1.21 to 7.57, p = 0.017), small neck size (OR: 0.56, 95% CI: 0.37 to 0.85, p = 0.007), and aneurysms in the posterior communicating artery (PcomA) (OR: 4.92, 95% CI: 1.19 to 20.18, p = 0.027) and anterior communicating artery (AcomA) (OR: 12.08, 95% CI: 2.99 to 48.79, p < 0.001) compared with the internal carotid artery without PcomA were significantly associated with IPR. The incidence of IPR was similar between the non-BGC and BGC groups (0.9% vs. 0.8%, p = 0.822); however, leveraging BGC was significantly associated with lower morbidity and mortality rates after IPR (0% vs. 44%, p = 0.033). Discussion: The incidence of IPR was relatively low. A bleb, small aneurysm neck, and location on PcomA and AcomA are independent risk factors for IPR. The use of BGC may prevent fatal clinical deterioration and achieve better clinical outcomes in patients with IPR.

5.
J Neurointerv Surg ; 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38262727

RESUMO

BACKGROUND: An intermediate catheter (IMC) can improve the maneuverability and stability of the microcatheter. OBJECTIVE: To investigate the efficacy and safety of using an IMC in triaxial systems for coil embolization of unruptured cerebral aneurysms (UCAs). METHODS: A total of 2430 consecutive saccular UCAs (2259 patients) that underwent initial coil embolization at three institutions between November 2003 and May 2023 were retrospectively reviewed. Patients were classified into two groups: with IMC (IMC(+)) and without IMC (IMC(-)). To investigate whether IMC use increased the rate of complete occlusion and the packing density, a propensity score-matched analysis was used to control for clinical, anatomical, and procedural features. RESULTS: Ultimately, 595 (24.5%) coil embolization used an IMC. Propensity score matching was successful for 424 paired IMC(+) and IMC(-) aneurysms. Compared with the IMC(-) group, the IMC(+) group had significantly higher rate of Raymond-Roy Occlusion Classification class 1 immediately after treatment (30.0% vs 20.8%, P=0.003) and at 6 months (28.8% vs 20.0%, P=0.004) and a higher volume embolization ratio (27.2% (SD 6.5%) vs 25.9% (SD 6.2%), P=0.003). Re-treatment rates were not significantly different between the two groups (0.7% vs 0.2%, P=0.624). No significant differences in the incidences of ischemic and hemorrhagic complications and IMC-related parent artery dissection were found between the two groups. CONCLUSION: Use of IMCs in triaxial systems can provide effective and safe support in coil embolization of UCAs because complete occlusion and dense coil packing can be achieved without increased complications.

6.
J Am Chem Soc ; 146(3): 2237-2247, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38196121

RESUMO

The acetal (O-glycoside) bonds of glycans and glycoconjugates are chemically and biologically vulnerable, and therefore C-glycosides are of interest as more stable analogs. We hypothesized that, if the O-glycoside linkage plays a vital role in glycan function, the biological activities of C-glycoside analogs would vary depending on their substituents. Based on this idea, we adopted a "linkage-editing strategy" for the creation of glycan analogs (pseudo-glycans). We designed three types of pseudo-glycans with CH2 and CHF linkages, which resemble the O-glycoside linkage in terms of bond lengths, angles, and bulkiness, and synthesized them efficiently by means of fluorovinyl C-glycosylation and selective hydrogenation reactions. Application of this strategy to isomaltose (IM), an inducer of amylase expression, and α-GalCer, which activates iNKT cells, resulted in the discovery of CH2-IM, which shows increased amylase production ability, and CHF-α-GalCer, which shows activity opposite that of native α-GalCer, serving as an antagonist of iNKT cells.


Assuntos
Galactosilceramidas , Glicosídeos , Polissacarídeos , Glicosilação , Polissacarídeos/química , Amilases/metabolismo
7.
Oper Neurosurg (Hagerstown) ; 26(2): 180-187, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37819087

RESUMO

BACKGROUND AND OBJECTIVES: Planning/guidance software became important tools for physicians' presurgical optimal decision-making. However, there are no intracranial stent products with specifically associated simulation software. We report the "premarket" clinical trial of a new braided stent with a customized simulation software. METHODS: A stent system with 3 mesh density types (16, 24, and 32 wire mesh) was designed based on computational flow dynamics technology, and a simulation software (virtual stent planner [VSP]) was developed for the optimal stent deployment planning. Stents were selected after simulation on preoperative 3D-processed angioimages, and accuracy of the VSP was evaluated. RESULTS: Thirty-three unruptured intracranial aneurysms were successfully treated with VSP guidance. Twenty aneurysms (61%) were anterior circulation aneurysms, and 13 (39%) were posterior circulation aneurysms. The average aneurysm size was 7.1 mm, and the mean follow-up period was 19.2 months (11-39.0). There was no major recurrence or retreatment during follow-up, 2 morbidity cases, and no mortality. VSP planning presented slightly smaller stent dimensions compared with postdeployment: 24.2 vs 25.5 mm average, error -1.3 mm, and difference rate-5.46%. CONCLUSION: Based on this result, the new stents and software guidance system were approved by the Ministry of Health and Welfare as a combined medical device. VSP provided precise deployment with minimal error compared with actual stent and can contribute to better stent deployment even for less experienced physicians.


Assuntos
Embolização Terapêutica , Aneurisma Intracraniano , Humanos , Embolização Terapêutica/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Estudos Prospectivos , Software , Stents
8.
RSC Adv ; 13(40): 27828-27838, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37731829

RESUMO

The intramolecular Diels-Alder reaction (IMDA) is a powerful method for regioselective and stereoselective construction of functionalised decalin skeletons, and the recent discovery of enzymes that catalyse IMDA cycloaddition in biosynthesis has generated considerable interest. This study focused on the role of the absolute configuration of the C-6 carbon of the substrate polyene in the stereocontrol of the IMDA reaction catalysed by Fsa2 and Phm7, which construct different enantiomeric decalin skeletons. Their enantiomeric precursor polyenes were synthesised and subjected to enzymatic or thermal IMDA reactions to isolate various diastereomeric decalines and determine their absolute configuration. Furthermore, density functional theory calculations were performed to elucidate the stereocontrol mechanism underlying the formation of decalin. The results showed that Fsa2 exhibits the same equisetin-type stereoselectivity for enantiomeric substrates regardless of the 6-methyl group configuration of the substrate, while Phm7 shows two types of stereoselectivity depending on the configuration of the 6-methyl group. We also found a unique stereochemistry-activity relationship in antibacterial activity for decalin diastereomers, including new derivatives. This study provides new insights into the stereoselectivity of DAase, which is important in the synthesis of natural product skeletons.

9.
PLoS One ; 18(8): e0290851, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37651399

RESUMO

Decalin-containing tetramic acid is a bioactive scaffold primarily produced by filamentous fungi. The structural diversity of this group of compounds is generated by characteristic enzymes of fungal biosynthetic pathways, including polyketide synthase/nonribosomal peptide synthetase hybrid enzymes and decalin synthase, which are responsible for the construction of a linear polyenoyl tetramic acid structure and stereoselective decalin formation via the intramolecular Diels-Alder reaction, respectively. Compounds that differed only in the decalin configuration were collected from genetically engineered mutants derived from decalin-containing tetramic acid-producing fungi and used for a structure-activity relationship study. Our evaluation of biological activities, such as cytotoxicity against several cancer cell lines and antibacterial, antifungal, antimalarial, and mitochondrial inhibitory activities, demonstrated that the activity for each assay varies depending on the decalin configurations. In addition to these known biological activities, we revealed that the compounds showed inhibitory activity against the insect steroidogenic glutathione S-transferase Noppera-bo. Engineering the decalin configurations would be useful not only to find derivatives with better biological activities but also to discover overlooked biological activities.


Assuntos
Antibacterianos , Glutationa Transferase , Animais , Glutationa Transferase/genética , Insetos
10.
J Antibiot (Tokyo) ; 76(6): 346-350, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37020042

RESUMO

A new decalin-containing secondary metabolite, wakodecaline C, was isolated from a fungus Pyrenochaetopsis sp. RK10-F058 by screening structurally interesting metabolites based on LC/MS profiling. The structure including the absolute configuration was determined by a combination of spectroscopic methods including NMR and mass spectrometry, chemical reaction, and calculation of ECD spectra. Wakodecaline C has unique structural features containing a tetrahydrofuran-fused decalin skeleton and tetramic acid moiety, which are connected through a double bond. The compound showed moderate cytotoxicity against HL-60 cells and antimalarial activity against the Plasmodium falciparum 3D7 strain.


Assuntos
Ascomicetos , Humanos , Estrutura Molecular , Ascomicetos/química , Naftalenos/química , Furanos/farmacologia
11.
Clin Neurol Neurosurg ; 225: 107583, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36603337

RESUMO

OBJECTIVE: To evaluate the static and dynamic features of blood blister-like aneurysms (BBAs) using cerebral angiography to identify characteristic features to improve the diagnosis of these uncommon aneurysms. METHODS: Digital subtraction angiography (DSA) images were compared between patients with BBAs (n = 12, group A) and patients with unruptured paraclinoid aneurysms ≤ 5 mm in size treated by endovascular procedures (n = 12, group B). DSA images were assessed for irregularities in the diameter of the parent artery and delayed inflow and outflow of contrast medium in the aneurysm. Enlargement of the aneurysm and morphological changes from the first assessment were also evaluated in patients with BBAs. RESULTS: Compared to the group B, group A had a higher proportion of irregular vessel diameter (p = 0.013) and the delayed contrast medium outflow (p = 0.014). As well, stagnation of contrast medium along the aneurysm wall was a characteristic finding of BBAs, even for small aneurysms. CONCLUSION: Irregular morphological features of the parent artery and delayed contrast medium outflow as characteristic findings of ruptured BBAs may improve the diagnosis of these uncommon aneurysms, which remains challenging in practice.


Assuntos
Aneurisma Roto , Aneurisma Intracraniano , Humanos , Angiografia Cerebral/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/cirurgia , Artérias , Angiografia Digital , Estudos Retrospectivos , Artéria Carótida Interna
12.
Case Rep Neurol Med ; 2023: 1787738, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36704418

RESUMO

Moyamoya disease is often diagnosed after intracranial hemorrhage in adult patients. Here, we report a case of unilateral moyamoya disease treated with indirect revascularization combined with cranioplasty after treatment for acute subdural hematoma and subcortical hemorrhage. A middle-aged woman with disturbed consciousness was transferred to our hospital. Computed tomography (CT) revealed an acute subdural hematoma with left temporoparietal subcortical hemorrhage. Three-dimensional CT angiography indicated a scarcely enhanced left middle cerebral artery (MCA) that was suspected to be delayed or nonfilling due to increased intracranial pressure. Subsequently, hematoma evacuation and external decompression were performed. Postoperative digital subtraction angiography (DSA) revealed stenosis of the left MCA and moyamoya vessels, indicating unilateral moyamoya disease. Forty-five days after the initial procedure, we performed encephalo-arterio-synangiosis (EAS) using the superficial temporal artery simultaneously with cranioplasty for the skull defect. The modified Rankin Scale score of the patient one year after discharge was 1, and the repeat DSA showed good patency of the EAS. Revascularization using EAS in the second step can be an option for revascularization for hemorrhagic moyamoya disease if the patient required cranioplasty for postoperative skull defect after decompressive craniotomy.

13.
J Plast Surg Hand Surg ; 57(1-6): 225-229, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35195058

RESUMO

BACKGROUND: An irreparable scaphoid proximal pole is challenging to treat because of the fragment size and limited blood supply. Salvage surgery, such as partial wrist fusion or proximal row carpectomy, may be performed but is not ideal for young patients. There are few reports of proximal scaphoid reconstruction using rib osteochondral grafts. METHODS: Four patients were treated with rib osteochondral graft for reconstruction of the scaphoid proximal pole. The patients had a mean postoperative follow-up of 24 months. The mean age at the time of surgery was 30 years. Outcome measurements included total active range of wrist motion arc, grip strength, and wrist function score. We also evaluated the progression of osteoarthritis and changes in carpal height. RESULTS: No complications occurred at the donor site. The range of motion improved from 82° to 95° before and after surgery. Grip strength improved from 22 kg to 33 kg before and after surgery. There was a remarkable improvement in the modified wrist function scores of Green and O'Brien from 40 points to 70 points before and after surgery. No progression of arthrosis was seen on the radiographs of all the patients. There was no significant difference in the carpal height ratio before and after surgery. CONCLUSIONS: Proximal scaphoid fractures may require reconstruction of the articular surfaces of the radius, capitate, and lunate. Reconstruction with a rib osteochondral graft is flexible, easy to fabricate, and can reconstruct the three articular surfaces.


Assuntos
Fraturas não Consolidadas , Osso Semilunar , Osteoartrite , Osso Escafoide , Humanos , Adulto , Osso Escafoide/diagnóstico por imagem , Osso Escafoide/cirurgia , Punho , Articulação do Punho/diagnóstico por imagem , Articulação do Punho/cirurgia , Osso Semilunar/cirurgia , Osteoartrite/diagnóstico por imagem , Osteoartrite/cirurgia , Costelas , Amplitude de Movimento Articular , Fraturas não Consolidadas/cirurgia , Resultado do Tratamento
14.
Nagoya J Med Sci ; 84(4): 884-889, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36544602

RESUMO

Thromboembolic complications are a concern in the treatment of cerebral aneurysms using a flow diverter. In this study, we report a case of abnormal foreshortening of a Flow Re-Direction Endoluminal Device (FRED) caused by in-stent thrombosis immediately after its deployment. A 72-year-old woman had a large cavernous carotid aneurysm, which caused ptosis and diplopia. FRED deployment was planned, and dual antiplatelet therapy was initiated 2 weeks before the procedure. Under systemic heparinization, FRED was deployed with local compaction over the aneurysm orifice. Cone-beam computed tomography subsequently revealed slightly poor wall apposition at the proximal side. While the balloon catheter was prepared for angioplasty, the stent became abnormally foreshortened, the proximal side slipped into the aneurysm, and the internal carotid artery became occluded. FRED was removed using a snare wire, and recanalization was obtained. The lumen of the removed FRED was filled with thrombus. The antiplatelet therapy was changed to triple regimen, and a Pipeline Flex embolization device was placed 1 month later. At that time, no thromboembolic complications were noted. It was considered that thrombotic occlusion was followed by foreshortening of FRED on the distal side because of antegrade blood flow. Multiple factors, such as increased mesh density by locally compacted stent deployment, slightly poor wall apposition, clopidogrel resistance, and the dual-layer structure of FRED, may have been involved in thrombus formation.


Assuntos
Procedimentos Endovasculares , Aneurisma Intracraniano , Trombose , Feminino , Humanos , Idoso , Stents/efeitos adversos , Prótese Vascular , Procedimentos Endovasculares/métodos , Aneurisma Intracraniano/cirurgia , Trombose/etiologia , Trombose/terapia , Resultado do Tratamento
15.
J Stroke Cerebrovasc Dis ; 31(11): 106790, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36156445

RESUMO

OBJECTIVES: Early detection of hemorrhagic transformation (HT) in patients with large vessel occlusion (LVO) after endovascular treatment is important for postoperative patient management. We investigated the diagnostic performance of intraoperative cone beam computed tomography (CBCT) with reference standard magnetic resonance imaging (MRI) for detecting HT. MATERIALS AND METHODS: Consecutive patients with LVO treated by endovascular treatment who underwent intraoperative CBCT and postoperative MRI were included. Two observers evaluated all images for the presence of HT. Sensitivity and specificity for detecting HT were calculated with MRI as reference standard. The observers classified HT according to the European Cooperative Acute Stroke Study (ECASS). Inter-method and inter-rater agreement for the detection of HT and for the ECASS classification were assessed using kappa or weighted Brennan-Prediger (wBP) statistics. RESULTS: Images of 106 procedures (94 for anterior circulation) were analyzed. The sensitivity and specificity for detecting HT on CBCT were 0.77 and 0.83, respectively, for all procedures and 0.83 and 0.8, respectively, for anterior circulation. The inter-method agreement for HT detection (κ = 0.63 overall, κ = 0.69 anterior circulation) and ECASS classification (wBP = 0.67 overall, wBP = 0.77 anterior circulation) were substantial. The inter-rater agreement for HT detection (κ = 0.87 overall, κ = 0.85 anterior circulation) and for ECASS classification (wBP = 0.95 overall, wBP = 0.92 anterior circulation) were almost perfect. CONCLUSIONS: The diagnostic performance of CBCT for the detection of HT in stroke patients treated for LVO was acceptable with excellent inter-rater agreement. Intraoperative CBCT may be useful to trigger early interventions if HT is detected, although detailed classifications of HT may be difficult.


Assuntos
Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Tomografia Computadorizada de Feixe Cônico/métodos , Imageamento por Ressonância Magnética , Sensibilidade e Especificidade , Estudos Retrospectivos
16.
Tech Hand Up Extrem Surg ; 26(3): 193-201, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35696616

RESUMO

Thumb carpometacarpal (CMC) joint instability is thought to be a debilitating disorder and, if left untreated, develops joint persistent synovitis and osteoarthritis. In this study, we report a novel surgical technique reconstructing the anterior oblique ligament, the dorsoradial ligament, and the intermetacarpal ligament simultaneously using both the transverse carpal ligament, and the palmaris longus tendon. Six patients with a mean age of 44 years showing no osteoarthritic changes by the radiographical examination underwent our anatomical three ligaments reconstruction for persistent painful thumb CMC joint instability. Clinical results with the mean follow-up of 20 months demonstrated that the pain was subjectively improved in all patients, both the grip and the pinch strength were increased significantly and good functional motion of the thumb could be observed after the operation. These findings indicated that our surgical procedure could be one option of treatment of the symptomatic CMC joint instability in early-stage arthritis.


Assuntos
Articulações Carpometacarpais , Instabilidade Articular , Osteoartrite , Procedimentos de Cirurgia Plástica , Adulto , Articulações Carpometacarpais/cirurgia , Humanos , Instabilidade Articular/cirurgia , Ligamentos/cirurgia , Ligamentos Articulares/cirurgia , Osteoartrite/cirurgia , Polegar/cirurgia
17.
Plant Cell Physiol ; 63(8): 1078-1090, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35660918

RESUMO

The response regulator RpaB plays a central role in transcriptional regulation of photosynthesis-related genes in cyanobacteria. RpaB is phosphorylated by its cognate histidine kinase Hik33 and functions as both an activator and a repressor under low-light conditions, whereas its phosphorylation level and DNA-binding activity promptly decrease upon the upshift of photon flux density, causing changes in the gene expression profile. In this study, we assessed the possibility of redox regulation of the DNA-binding activity of RpaB in Synechocystis sp. PCC 6803 by the addition of inhibitors of photosynthetic electron transport, 3-(3,4-dichlorophenyl)-1,1-dimethylurea and 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone, or the reducing agent dithiothreitol under different photon flux densities. Analysis of the phosphorylation level of RpaB revealed that reduction of QA and increase in the availability of reducing equivalents at the acceptor side of photosystem I (PSI) can independently trigger dephosphorylation. The redox-state-dependent regulation by an unidentified thiol other than Cys59 of RpaB is prerequisite for the phosphorylation-dependent regulation of the DNA-binding activity. Environmental signals, recognized by Hik33, and metabolic signals recognized as the availability of reducing equivalents, must be integrated at the master regulator RpaB, in order to attain the flexible regulation of acclimatory responses.


Assuntos
Synechocystis , Proteínas de Bactérias/metabolismo , DNA/metabolismo , Regulação Bacteriana da Expressão Gênica , Luz , Oxirredução , Fotossíntese , Synechocystis/metabolismo
18.
Oper Neurosurg (Hagerstown) ; 22(3): 115-122, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34989707

RESUMO

BACKGROUND: Indocyanine green (ICG) videoangiography is rarely used during the surgical treatment of thoracic outlet syndrome (TOS). OBJECTIVE: To evaluate subclavian artery (SA) flow dynamics using the analytical ICG videoangiography during TOS surgeries. METHODS: We examined patients with neurogenic TOS who received surgical treatment and whose SA blood flow at the interscalene space was evaluated using ICG videoangiography equipped with an analytical function (FLOW800). Anterior scalenectomy with or without middle scalenectomy and first rib resection were conducted for decompression of the brachial plexus. ICG videoangiography was performed before and after decompression of the brachial plexus. After acquisition of grayscale and color-coded maps, a region of interest was placed in the SA to obtain time-intensity diagrams. Maximum intensity (MI), rise time (RT), and blood flow index (BFi) were calculated from the diagram, in arbitrary intensity (AI) units. We compared values before and after decompression. Comparisons of the three parameters before and after decompression were assessed statistically using the paired t-tests and Wilcoxon signed-rank test. RESULTS: We evaluated nine procedures in consecutively presenting patients. The observed mean values of MI, RT, and BFi before decompression were 174.1 ± 61.5 AI, 5.2 ± 1.1 s, and 35.2 ± 13.5 AI/s, respectively, and the observed mean values of MI, RT, and BFi after decompression were 299.3 ± 167.4 AI, 6.6 ± 0.8 s, and 44.6 ± 28.3 AI/s, respectively. These parameters showed higher values after decompression than before decompression, and the increase in MI and RT was statistically significant (P < .05). CONCLUSION: ICG videoangiography allows semiquantitative evaluation of hemodynamic changes during TOS surgery. A marked decrease in the velocity of SA flow was observed after decompression.


Assuntos
Plexo Braquial , Síndrome do Desfiladeiro Torácico , Humanos , Verde de Indocianina , Costelas/cirurgia , Artéria Subclávia/diagnóstico por imagem , Artéria Subclávia/cirurgia , Síndrome do Desfiladeiro Torácico/diagnóstico por imagem , Síndrome do Desfiladeiro Torácico/cirurgia
19.
Neurol Sci ; 43(1): 593-601, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33973077

RESUMO

BACKGROUND: Severe low back pain (LBP) is an occasional complaint in patients with neuromuscular disorders (NMDs). Accurate diagnosis and treatment are required to manage LBP; however, the precise pathophysiology differs for each patient. This study aimed to evaluate the efficacy of lumbar facet joint denervation (FJD) and adjunctive modalities in the treatment of LBP in patients with NMD-associated kyphoscoliosis. METHODS: A total of 16 patients (22 sites) with NMD (bilateral, n = 6; unilateral, n = 10) and LBP treated with lumbar FJD were evaluated. The patients were divided into two groups: those treated with FJD alone (group 1) and those treated with multimodal treatment, including FJD along with radiofrequency ablation for sacroiliac joint pain, piriform muscle block, botulinum toxin injection into the paraspinal muscles, spinal cord stimulation, or any of their combinations (group 2). All patients were followed up for 48 weeks postoperatively. The two groups were compared with respect to the duration required for improvements in LBP by more than 50% (numerical rating scale ≤ 5). RESULTS: There was no significant difference between the groups regarding the age, duration since the onset of Parkinson's syndrome, and radiographic analysis. The effective period of improved pain was greater in group 2 than in group 1 (30.7 vs. 8.4 weeks, P < 0.01). CONCLUSIONS: Multimodal treatment including FJD is safe and relatively effective in patients with NMD-associated kyphoscoliosis. Hence, it is a potential substitute for conventional spinal fixation surgery, which has a higher risk of complications.


Assuntos
Dor Lombar , Articulação Zigapofisária , Terapia Combinada , Denervação , Humanos , Dor Lombar/cirurgia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Articulação Zigapofisária/diagnóstico por imagem , Articulação Zigapofisária/cirurgia
20.
Interv Neuroradiol ; 28(3): 323-331, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34515567

RESUMO

BACKGROUND: We examined compliance differences among balloon remodeling microcatheters, which have not been established previously. METHODS: Straight and 120° angulated vascular models were created in a 3 mm diameter tube with 3 mm hole (vascular model A), a tube with a 4 mm hole (vascular model B), and a 4 mm diameter tube (vascular model C). We compared the pressure exerted when each balloon was herniated 1 or 2 mm between three compliant balloons (SHOURYU SR, TransForm C, and Scepter C) and four super-compliant balloons (HyperForm, SHOURYU HR, TransForm SC, and Scepter XC). RESULTS: In vascular model A, there was a significant difference in the pressure exerted by compliant balloons and super-compliant balloons in both the straight and angulated models. In the straight model (1 and 2 mm), the lowest pressure was exerted by HyperForm (super-compliant balloons group) and SHOURYU SR (compliant balloons group). The lowest pressure was exerted in the angulated model by HyperForm (super-compliant balloons group) and Scepter C (compliant balloons group). The Scepter balloon exerted higher pressure in the straight model than other balloon remodeling microcatheters but less in the angulated model. In vascular model B, the pressure decreased in all balloons compared with model A. In vascular model C, the pressure increased in all balloons compared with model A. CONCLUSIONS: Pressure differed across balloon remodeling microcatheters. In addition, vessel shape and diameter, and hole size, affected the results. Our findings can help select balloon remodeling microcatheters.


Assuntos
Modelos Teóricos , Humanos
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