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1.
Intern Med ; 63(5): 665-669, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38171870

RESUMO

This case illustrates the complex interactions of the immune responses after vaccination and highlights their potential connections to various autoimmune conditions. A 22-year-old man with quiescent ulcerative colitis (UC) presented with abdominal pain, rectal bleeding, and thrombocytopenia 7 days after receiving the third coronavirus disease 2019 mRNA vaccination. Laboratory data confirmed the diagnosis of immune thrombocytopenia. High-dose intravenous immunoglobulin administration boosted the patient's platelet count. Simultaneously, colonoscopy revealed that his UC had relapsed. Although salazosulfapyridine briefly improved his symptoms, his stool frequency worsened one week later. The patient also developed pyoderma gangrenosum. Subsequent treatment with infliximab notably improved both pyoderma gangrenosum and UC.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Colite Ulcerativa , Púrpura Trombocitopênica Idiopática , Pioderma Gangrenoso , Trombocitopenia , Adulto , Humanos , Masculino , Adulto Jovem , Doença Crônica , Colite Ulcerativa/complicações , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/diagnóstico , COVID-19/complicações , Vacinas contra COVID-19/efeitos adversos , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Púrpura Trombocitopênica Idiopática/etiologia , Pioderma Gangrenoso/tratamento farmacológico , Pioderma Gangrenoso/etiologia , Pioderma Gangrenoso/diagnóstico , Recidiva
2.
Nat Struct Mol Biol ; 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38062209

RESUMO

The recycling of membrane proteins from endosomes to the cell surface is vital for cell signaling and survival. Retriever, a trimeric complex of vacuolar protein-sorting-associated protein (VPS)35L, VPS26C and VPS29, together with the CCC complex comprising coiled-coil domain-containing (CCDC)22, CCDC93 and copper metabolism domain-containing (COMMD) proteins, plays a crucial role in this process. The precise mechanisms underlying retriever assembly and its interaction with CCC have remained elusive. Here, we present a high-resolution structure of retriever in humans determined using cryogenic electron microscopy. The structure reveals a unique assembly mechanism, distinguishing it from its remotely related paralog retromer. By combining AlphaFold predictions and biochemical, cellular and proteomic analyses, we further elucidate the structural organization of the entire retriever-CCC complex across evolution and uncover how cancer-associated mutations in humans disrupt complex formation and impair membrane protein homeostasis. These findings provide a fundamental framework for understanding the biological and pathological implications associated with retriever-CCC-mediated endosomal recycling.

3.
Artigo em Inglês | MEDLINE | ID: mdl-37948001

RESUMO

OBJECTIVE: We evaluated the blood flow within the downstream aortic false lumen after frozen elephant trunk repair for acute aortic dissection and identified hemodynamic predictors of false lumen expansion and negative false lumen remodeling using four-dimensional flow magnetic resonance imaging. METHODS: Thirty-one patients (Stanford type A, n = 28; Stanford type B, n = 3) with patent false lumen who underwent frozen elephant trunk procedures for acute aortic dissection were included in this observational study. Each patient underwent computed tomography during the follow-up period and four-dimensional flow magnetic resonance imaging within 3 postoperative months. The false lumen volumetric expansion rate was calculated using computed tomography data. The direction and the rate of flow in the lower descending aortic false lumen were analyzed. Negative false lumen remodeling was defined as a volumetric increase of > 10% from the baseline volume. RESULTS: Negative false lumen remodeling had developed in 6 of the 31 patients during the observation period. Most of the false lumen flows were biphasic during systole. The range between peak and nadir flow rates was associated with the false lumen volumetric expansion rate (ß coefficient = 6.77; p < 0.01, R2 = 0.43). CONCLUSIONS: The range between peak and nadir flow rates may serve as a hemodynamic predictor of negative false lumen remodeling, enabling further treatment for patients at risk of expansion in the downstream aorta.

4.
Res Sq ; 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37397996

RESUMO

The recycling of membrane proteins from endosomes to the cell surface is vital for cell signaling and survival. Retriever, a trimeric complex of VPS35L, VPS26C and VPS29, together with the CCC complex comprising CCDC22, CCDC93, and COMMD proteins, plays a crucial role in this process. The precise mechanisms underlying Retriever assembly and its interaction with CCC have remained elusive. Here, we present the first high-resolution structure of Retriever determined using cryogenic electron microscopy. The structure reveals a unique assembly mechanism, distinguishing it from its remotely related paralog, Retromer. By combining AlphaFold predictions and biochemical, cellular, and proteomic analyses, we further elucidate the structural organization of the entire Retriever-CCC complex and uncover how cancer-associated mutations disrupt complex formation and impair membrane protein homeostasis. These findings provide a fundamental framework for understanding the biological and pathological implications associated with Retriever-CCC-mediated endosomal recycling.

5.
Exp Ther Med ; 26(1): 360, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37324514

RESUMO

Primary central nervous system lymphoma (PCNSL) is a rare and aggressive type of intracranial tumor. However, PCNSL is radiosensitive; thus, whole-brain radiotherapy (WBRT) is often selected as an alternative consolidation therapy. WBRT-related delayed neurotoxicity can affect the quality of life of the elderly. 5-aminolevulinic acid (ALA) is a natural precursor of heme and has been widely used as a live molecular fluorescence marker in brain tumor surgery. Experimental studies have demonstrated that combination therapy with 5-ALA and ionizing irradiation (IR), denoted radiodynamic therapy (RDT), resulted in tumor suppression in cancer, including glioma, melanoma, colorectal cancer, prostate cancer, breast cancer and lung cancer; however, to the best of our knowledge, this method has not been investigated in lymphoma. The present study aimed to investigate the radiodynamic effect of 5-ALA on lymphoma cells in vitro. The synthesis of 5-ALA-induced protoporphyrin IX (PpIX) was assessed under normal and hypoxic conditions in lymphoma cells (Raji, HKBML and TK). Subsequently, the radiodynamic effect of 5-ALA was evaluated using a colony formation assay and reactive oxygen species (ROS) production after RDT was examined using flow cytometry. Finally, the mitochondrial density in the lymphoma cells was evaluated. Lymphoma cells exhibited a high accumulation of 5-ALA-induced PpIX in the flow cytometric analysis, and a decrease in the surviving fraction under IR in cells with 5-ALA treatment compared with cells not treated with 5-ALA in the colony formation assay under normal and hypoxic conditions. Although ROS production 12 h after IR was increased compared with that immediately after IR (0 h), pretreatment with 5-ALA enhanced the delayed ROS production in each lymphoma cell line under normoxic conditions. Raji and TK cells exhibited an increase in ROS production 12 h after IR compared with that at 0 h in the 5-ALA-untreated cells under hypoxic conditions. Raji, HKBML and TK cells exhibited an increase in ROS production 12 h after IR compared with that at 0 h in the 5-ALA-treated cells, while TK cells exhibited enhancement of ROS production 12 h after IR in 5-ALA-treated cells compared with 5-ALA-untreated cells under hypoxic conditions. Other studies have demonstrated that impaired mitochondria damaged by IR produce ROS via the metabolic process, then damage the rest of the surrounding normal mitochondria, consequently propagating oxidative stress within tumor cells and leading to cell death. Thus, we hypothesized that the propagating oxidative stress after IR was associated with mitochondrial density in tumor cells. Namely, high accumulation of 5-ALA-indcued PpIX may promote ROS production in mitochondria of tumor cells after IR, and suppress the cell surviving fraction via the propagation of oxidative stress. In the colony formation assay, Raji cell colony formation was suppressed by RDT with 5-ALA. Simultaneously, the mitochondrial density in the Raji cells was higher than that in other cell lines. Pretreatment with 5-ALA enhanced delayed ROS production after IR in lymphoma cells under normoxic conditions. Under hypoxic conditions, only TK cells exhibited enhancement of ROS production 12 h after IR in the 5-ALA-treated group compared with the 5-ALA-untreated group. Although further studies evaluating the effect of hypoxic conditions in lymphoma cells are needed, the results suggested that RDT with 5-ALA could suppress colony formation under normal and hypoxic conditions in lymphoma cells. Therefore, RDT with 5-ALA is a potential treatment option for PCNSL.

6.
bioRxiv ; 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37333304

RESUMO

The recycling of membrane proteins from endosomes to the cell surface is vital for cell signaling and survival. Retriever, a trimeric complex of VPS35L, VPS26C and VPS29, together with the CCC complex comprising CCDC22, CCDC93, and COMMD proteins, plays a crucial role in this process. The precise mechanisms underlying Retriever assembly and its interaction with CCC have remained elusive. Here, we present the first high-resolution structure of Retriever determined using cryogenic electron microscopy. The structure reveals a unique assembly mechanism, distinguishing it from its remotely related paralog, Retromer. By combining AlphaFold predictions and biochemical, cellular, and proteomic analyses, we further elucidate the structural organization of the entire Retriever-CCC complex and uncover how cancer-associated mutations disrupt complex formation and impair membrane protein homeostasis. These findings provide a fundamental framework for understanding the biological and pathological implications associated with Retriever-CCC-mediated endosomal recycling.

7.
J Neurooncol ; 162(2): 425-433, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37052748

RESUMO

PURPOSE: Pineal parenchymal tumors of intermediate differentiation (PPTIDs), which were recognized in the 2007 World Health Organization (WHO) classification, are rare, accounting for less than 1% of all central nervous system tumors. This rarity and novelty complicate the diagnosis and treatments of PPTID. We therefore aimed to evaluate the clinicopathological significance of this tumor. METHODS: At 11 institutions participating in the Kyushu Neuro-Oncology Study Group, data for patients diagnosed with PPTID were collected. Central pathology review and KBTBD4 mutation analysis were applied to attain the diagnostically accurate cohort. RESULTS: PPTID was officially diagnosed in 28 patients: 11 (39%) with WHO grade 2 and 17 (61%) with WHO grade 3 tumors. Median age was 49 years, and the male:female ratio was 1:2.1. Surgery was attempted in all 28 patients, and gross total resection (GTR) was achieved in 46% (13/28). Adjuvant radiotherapy and chemotherapy were administered to, respectively, 82% (23/28) and 46% (13/28). The 5-year progression-free survival (PFS) and overall survival rates were 64.9% and 70.4% respectively. Female sex (p = 0.018) and GTR (p < 0.01) were found to be independent prognostic factors for PFS and female sex (p = 0.019) was that for OS. Initial and second recurrences were most often leptomeningeal (67% and 100% respectively). 80% (20/25) of patients harbored a KBTBD4 mutation. CONCLUSIONS: Female sex and GTR were independent prognostic factors in our patients with PPTID. Leptomeningeal recurrence was observed to be particularly characteristic of this tumor. The rate of KBTBD4 mutation observed in our cohort was acceptable and this could prove the accuracy of our PPTID cohort.


Assuntos
Neoplasias Encefálicas , Glândula Pineal , Pinealoma , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Pinealoma/genética , Pinealoma/terapia , Pinealoma/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/diagnóstico , Estudos de Coortes , Intervalo Livre de Progressão , Glândula Pineal/patologia , Estudos Retrospectivos
8.
Oncol Lett ; 25(2): 47, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36644156

RESUMO

Primary central nervous system lymphoma (PCNSL) is a rare brain tumor that most commonly arises in the cerebral white matter, basal ganglia, peri-ventricle or corpus callosum. Confinement of PCNSL to the third ventricle is extremely rare, and seldom presents with intratumoral hemorrhage (ITH). The present study described the case of a 75-year-old woman who presented with obstructive hydrocephalus due to third-ventricle PCNSL. On magnetic resonance imaging (MRI), the tumor presented ITH on T2*-weighted images and a highly elevated regional cerebral blood volume on dynamic susceptibility contrast-enhanced MRI (DSC-MRI). Due to the high elevation of the regional cerebral blood volume, high-grade glioma was suspected as a preoperative diagnosis. The patient underwent endoscopic tumor biopsy and third ventricle PCNSL was successfully diagnosed. The patient achieved good prognosis at an early stage after the start of treatment initiation. There are many differential considerations for a third-ventricle tumor, and DSC-MRI can help the differential diagnosis of these tumors. Furthermore, the presence of ITH can lead to the inaccurate estimation of regional cerebral blood volume values. Overall, silent or microhemorrhage in PCNSL may be underestimated, and clinicians should therefore carefully evaluate tumor vascularity by MRI.

10.
Pharm Res ; 40(4): 863-871, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36002612

RESUMO

PURPOSE: Small extracellular vesicles (sEV) containing proteins and RNAs play important roles as intercellular signal mediators. A critical issue is that there are multiple methods to prepare sEV fractions. The purpose of this study was to examine whether cancer cell-derived sEV fractions prepared by different isolation methods show similar responses for the induction of inflammatory cytokines in macrophages. METHODS: sEV fractions from the conditioned medium of MCF-7 cells were prepared by ultracentrifugation (UC), the MagCapture Exosome Isolation Kit PS (PS), or the ExoQuick-TC kit (EQ). The mRNA levels of inflammatory cytokines in differentiated THP-1 cells treated with the sEV fractions were evaluated. RESULTS: The yields of sEV fractions obtained from 1 mL conditioned medium by UC, PS, or EQ were 3.2×108 particles (0.27 µg protein), 12.8×108 particles (0.87 µg protein) and 23.5 ×108 particles (4.50 µg protein), respectively. The average particle sizes in the UC, PS, and EQ fractions were 184.8 ± 1.8 nm, 157.8 ± 1.3 nm and 165.8 ± 1.1 nm, respectively. CD9 and CD81, markers of sEV, were most highly detected in the PS fraction, followed by the EQ and UC fractions. These results suggest that PS gave sEV with relatively high purity, and many protein contaminants appear to be included in the EQ fraction. The mRNA levels of inflammatory cytokines in THP-1 macrophages were most prominently increased by treatment with the UC fraction, followed by the EQ and PS fractions, suggesting that contaminants rather than sEV may largely induce an inflammatory response. CONCLUSION: The isolation method affects the evaluation of sEV function.


Assuntos
Vesículas Extracelulares , Humanos , Meios de Cultivo Condicionados/metabolismo , Células MCF-7 , Vesículas Extracelulares/metabolismo , Citocinas/metabolismo , RNA Mensageiro/metabolismo , Inflamação/metabolismo
11.
Medicine (Baltimore) ; 101(45): e31743, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36397413

RESUMO

BACKGROUND: Spinal cord infarction is a rare central nervous system angiopathy that impairs motor, sensory, and autonomic nerves and occurs due to various reasons. This study reports a case of spinal cord infarction in a patient following myocardial infarction that was managed by veno-arterial extracorporeal membrane oxygenation (VA-ECMO). CASE SUMMARY: A 78-year-old Japanese man visited the emergency department with a complaint of chest tightness. He had a history of hypertension, dyslipidemia, diabetes, chronic renal failure, and postoperative bladder cancer. Myocardial infarction was diagnosed after ST elevation in lead aVR was identified by electrocardiogram during the visit, and cardiopulmonary arrest occurred twice during our examination and treatment. After percutaneous coronary intervention with an intra-aortic balloon pump and VA-ECMO, the patient was admitted to the intensive care unit. His circulation stabilized, and he was withdrawn from the intra-aortic balloon pump on day 3 of illness and from VA-ECMO on day 4. However, his consciousness remained impaired. When the patient's consciousness improved on day 14, lower limb weakness was identified. Magnetic resonance imaging conducted on the following day revealed spinal cord infarction in the 5th to 12th thoracic vertebrae. CONCLUSION: Spinal cord infarction due to VA-ECMO is extremely rare but has a poor neurological prognosis upon onset. Necessary countermeasures include conducting regular neurological examinations and high blood pressure maintenance, which is very difficult in VA-ECMO patients. Therefore, patient care will benefit from the experiences reported in such cases.


Assuntos
Oxigenação por Membrana Extracorpórea , Arteriosclerose Intracraniana , Ataque Isquêmico Transitório , Infarto do Miocárdio , Isquemia do Cordão Espinal , Masculino , Humanos , Idoso , Choque Cardiogênico/etiologia , Choque Cardiogênico/terapia , Oxigenação por Membrana Extracorpórea/métodos , Balão Intra-Aórtico/efeitos adversos , Infarto do Miocárdio/diagnóstico , Isquemia do Cordão Espinal/etiologia , Isquemia do Cordão Espinal/terapia , Arteriosclerose Intracraniana/complicações , Ataque Isquêmico Transitório/complicações
12.
Medicine (Baltimore) ; 101(29): e29617, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35866824

RESUMO

RATIONALE: Hemolytic anemia is a rare postoperative complication of aortic surgery, which may be caused by an excessively kinked graft that causes abnormal blood flow. It has been reported that 4-dimensional flow magnetic resonance imaging (4D flow MRI) can identify abnormal flow. Herein, we report the guidance of 4D flow MRI in performing the revision procedure for a patient with hemolytic anemia by evaluating abnormal blood flow based on this method. PATIENT CONCERNS: A 70-year-old woman presented with dizziness and fatigue. She had undergone total arch replacement with a frozen elephant trunk 5 years prior. We diagnosed hemolytic anemia caused by a kinked graft after total arch replacement. DIAGNOSIS: Although computed tomography findings revealed 3 lesions of the kinked graft at the ascending portion and cervical branches, 4D flow MRI findings showed that only the kinked graft at the ascending portion caused hemolytic anemia due to an elevated viscous energy loss around it. INTERVENTION: We performed surgery to remove the kinked section instead of revision surgery consisting of total arch replacement. OUTCOMES: The patient's postoperative course was uneventful and there were no complications. Postoperative enhanced computed tomography findings showed that the repaired graft had an adequate length and smoothly curved shape. The 4D flow MRI findings revealed smooth flow in the ascending portion and decreased viscous energy loss. LESSONS: Based on the 4D flow MRI findings, we adopted a less invasive approach, repairing only the ascending portion of the graft, instead of performing revision surgery comprising total arch replacement.


Assuntos
Anemia Hemolítica , Aneurisma da Aorta Torácica , Implante de Prótese Vascular , Idoso , Anemia Hemolítica/etiologia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Feminino , Humanos , Imageamento por Ressonância Magnética/efeitos adversos , Espectroscopia de Ressonância Magnética , Reoperação/efeitos adversos
13.
Lancet Gastroenterol Hepatol ; 7(3): 230-237, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34856196

RESUMO

BACKGROUND: A combination of endoscopic and histological evaluation is important in the management of patients with ulcerative colitis. We aimed to adapt our previous deep neural network system (deep neural ulcerative colitis [DNUC]) to full video colonoscopy and evaluate its validity in the real-time detection of histological mucosal inflammation. METHODS: In this multicentre, cross-sectional study, we prospectively enrolled consecutive patients (≥15 years) with ulcerative colitis who had an indication for colonoscopy at five hospitals in Japan. Patients in clinical remission were randomly assigned (1:2) to study 1 and study 2. Those with clinically active disease were assigned to study 2 only. Study 1 assessed the validity of real-time histological assessment using DNUC and study 2 validated the consistency of endoscopic scoring between DNUC and experts. The primary endpoint for study 1 was comparison of the results judged by DNUC (healing or active) with biopsy specimens evaluated by pathologists. In study 2, the primary endpoint was the ability of DNUC to determine the Ulcerative Colitis Endoscopic Index of Severity score compared with centrally evaluated scoring by inflammatory bowel disease endoscopy experts. FINDINGS: From April 1, 2020, to March 31, 2021, 770 patients (180 in study 1 and 590 in study 2) were enrolled. Using real-time histological evaluation, DNUC was able to evaluate the presence or absence of histological inflammation in 729 (81%) of 900 biopsy specimens. For predicting histological remission, the DNUC had a sensitivity of 97·9% (95% CI 97·0-98·5) and a specificity of 94·6% (91·1-96·9). Moreover, its positive predictive value was 98·6% (97·7-99·2) and negative predictive value was 92·1% (88·7-94·3). The intraclass correlation coefficient between DNUC and experts for endoscopic scoring was 0·927 (95% CI 0·915-0·938). INTERPRETATION: DNUC provided consistently accurate endoscopic scoring and showed potential for reducing the number of biopsies required. This system is an objective and consistent application for video colonoscopy that has potential for use in various medical situations. FUNDING: Tokyo Medical and Dental University and Sony.


Assuntos
Colite Ulcerativa/patologia , Colonoscopia , Redes Neurais de Computação , Gravação em Vídeo , Adulto , Biópsia , Estudos Transversais , Feminino , Humanos , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Distribuição Aleatória , Indução de Remissão , Sensibilidade e Especificidade
15.
J UOEH ; 43(4): 415-419, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34897170

RESUMO

Magnetic resonance imaging (MRI) features of meningiomas typically reveal a well-circumscribed and contrast-enhancing dural mass. Here we discuss the differences in MRI findings between typically benign and atypical meningioma, and their clinical implications. An MRI of a 67-year-old man revealed a substantial homogeneous enhancing tumor nodule. The MRI also showed two components in the tumor, and the regional cerebral blood volume (rCBV) was higher in the lateral than in the medial mass. A pathological examination also revealed features of both benign and atypical meningiomas. The Ki-67 labeling index was 1% on the medial side and 5% on the lateral side. There were clearly two components within the tumor mass, and the MRI revealed differential rCBV in the tumor. The results indicated a nontypical MRI of meningiomas, allowing for predictability of atypical meningiomas using MRI before surgical resection.


Assuntos
Neoplasias Meníngeas , Meningioma , Idoso , Volume Sanguíneo Cerebral , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Neoplasias Meníngeas/diagnóstico por imagem , Meningioma/diagnóstico por imagem
16.
Surg Neurol Int ; 12: 500, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34754550

RESUMO

BACKGROUND: Ewing's sarcoma (ES) is a malignancy that arises from bones or soft tissue, characterized by primitive small and round blue cells. Primary ES typically occurs in the long bones, vertebrae, or pelvis, and is extremely rare in the skull base. CASE DESCRIPTION: A 14-year-old girl presented with posterior cervical pain and dysfunction of multiple cranial nerves (CNs). Radiological investigation revealed a solid mass of the petroclival bone extending into the sphenoid sinus. The patient underwent endoscopic transsphenoidal surgery for diagnosis of the pathology, and partial resection was safely achieved. Histopathological, genetic, and radiological examinations confirmed the diagnosis of primary ES. Subsequently, the patient underwent adjuvant chemotherapy and radiotherapy following which the clinical symptoms resolved. Complete response was achieved after multimodal treatment. Twenty months after treatment, the patient remains in remission without recurrence or metastatic disease. Primary ES of the petroclival bone has been reported in only three cases in the literature. As seen in the present case, dysfunction of multiple CNs is the most common manifestation of petroclival ES. Diagnosis should be confirmed by histopathological and genetic examinations considering the nonspecific clinical symptoms and radiological features. CONCLUSION: Multimodal treatment, including surgery, chemotherapy, and radiotherapy, can result in favorable outcomes. Clinicians should consider safe resection during surgical management to prevent complications that can delay postoperative multimodal treatment.

17.
Neurol Med Chir (Tokyo) ; 61(12): 721-730, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34615810

RESUMO

The endovascular perforation (EP) model is a common technique for experimental subarachnoid hemorrhage (SAH) in rats, simulating the pathophysiological features observed in the acute phase of SAH. Due to the drawbacks of large variations in the amount of bleeding, the results obtained from this model require severity evaluation. However, no less-invasive procedure could confirm the precise intracranial conditions immediately after establishing the rat EP model. We created a novel method for evaluating SAH immediately after establishing the rat EP model using intra-arterial contrast-enhanced micro-computed tomography (CT). We administered contrast agents continuously via the carotid artery during surgery and performed CT examination immediately after SAH induction. First, bleeding severity was classified by establishing a scoring system based on the CT findings (cSAH scoring system). Subsequently, we determined the actual SAH distribution macroscopically and histologically and compared it with the cSAH scores. Second, we investigated the contrast agent's neurotoxicity in rats. Finally, we confirmed the correlation between cSAH scores and SAH severity, including neurological status, cerebral vasospasm, and hematoma volume 24 hr after SAH. Intra-arterial contrast-enhanced micro-CT could visualize the distribution of SAH proportionally to the bleeding severity immediately after establishing the EP model. Moreover, the contrast agent administration was determined not to be neurotoxic to rats. The cSAH scoring revealed a significant correlation with the SAH severity in the rat EP model (P <0.01). Thus, our minimally invasive method provided precise information on intracranial status in the ultra-early phase of SAH in rats EP model.


Assuntos
Hemorragia Subaracnóidea , Vasoespasmo Intracraniano , Animais , Pressão Sanguínea , Modelos Animais de Doenças , Ratos , Hemorragia Subaracnóidea/diagnóstico por imagem , Vasoespasmo Intracraniano/diagnóstico por imagem , Vasoespasmo Intracraniano/etiologia , Microtomografia por Raio-X
18.
Life Sci ; 284: 119896, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34450168

RESUMO

AIM: Abiraterone acetate for metastatic castration-resistant prostate cancer is an acetylated prodrug to be hydrolyzed to abiraterone. Abiraterone acetate is known to be hydrolyzed by pancreatic cholesterol esterase secreted into the intestinal lumen. This study aimed to investigate the possibility that arylacetamide deacetylase (AADAC) expressed in enterocytes contributes to the hydrolysis of abiraterone acetate based on its substrate preference. MATERIALS AND METHODS: Abiraterone acetate hydrolase activity was measured using human intestinal (HIM) and liver microsomes (HLM) as well as recombinant AADAC. Correlation analysis between activity and AADAC expression was performed in 14 individual HIMs. The in vivo pharmacokinetics of abiraterone acetate was examined using wild-type and Aadac knockout mice administered abiraterone acetate with or without orlistat, a pancreatic cholesterol esterase inhibitor. KEY FINDINGS: Recombinant AADAC showed abiraterone acetate hydrolase activity with similar Km value to HIM and HLM. The positive correlation between activity and AADAC levels in individual HIMs supported the responsibility of AADAC for abiraterone acetate hydrolysis. The area under the plasma concentration-time curve (AUC) of abiraterone after oral administration of abiraterone acetate in Aadac knockout mice was 38% lower than that in wild-type mice. The involvement of pancreatic cholesterol esterase in abiraterone formation was revealed by the decreased AUC of abiraterone by coadministration of orlistat. Orlistat potently inhibited AADAC, implying its potential as a perpetrator of drug-drug interactions. SIGNIFICANCE: AADAC is responsible for the hydrolysis of abiraterone acetate in the intestine and liver, suggesting that concomitant use of abiraterone acetate and drugs potently inhibiting AADAC should be avoided.


Assuntos
Acetato de Abiraterona/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Acetato de Abiraterona/sangue , Acetato de Abiraterona/química , Acetato de Abiraterona/farmacocinética , Adolescente , Adulto , Idoso , Androstenos/sangue , Animais , Carboxilesterase/metabolismo , Feminino , Humanos , Hidrólise , Concentração Inibidora 50 , Intestinos/efeitos dos fármacos , Cinética , Masculino , Camundongos Knockout , Microssomos Hepáticos/metabolismo , Pessoa de Meia-Idade , Orlistate/administração & dosagem , Orlistate/farmacologia , Proteínas Recombinantes/metabolismo
19.
Aliment Pharmacol Ther ; 54(8): 1052-1060, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34323301

RESUMO

BACKGROUND: Several studies have reported a positive correlation between serum drug concentrations and endoscopic remission in patients with Crohn's disease. AIM: To examine the association between the concentrations of cytokine blockers (infliximab, adalimumab and ustekinumab) and endoscopic remission of small bowel lesions. METHOD: This was a cross-sectional study conducted at a single tertiary referral centre. Patients with Crohn's disease who received maintenance cytokine blocker therapy were recruited from April 2018 to May 2020. We performed balloon-assisted enteroscopy and collected serum samples to measure drug concentrations. The primary endpoint was the relationship between the concentrations of cytokine blockers and endoscopic remission in the small bowel. RESULTS: We enrolled 143 patients, 66, 44 and 33 of whom were receiving infliximab, adalimumab and ustekinumab, respectively. Enteroscopic findings showed that the rate of endoscopic remission of small bowel lesions was significantly lower than that of colonic lesions (P < 0.01). For each agent, the mean drug concentration in patients exhibiting endoscopic remission in the small bowel was higher than that observed in patients with endoscopic remission in the colon (but not in the small bowel) or with any active disease (either in the small bowel, colon or both). Patients with infliximab, adalimumab and ustekinumab concentrations >5, 14 and 4 µg/mL were nearly 5.3-, 9.4- and 14.7-times more likely to exhibit endoscopic remission of the small bowel, respectively. CONCLUSIONS: Cytokine blocker treatment was less efficacious for small bowel inflammation than colonic inflammation. Higher serum concentrations were needed to achieve endoscopic remission of small bowel lesions.


Assuntos
Doença de Crohn , Citocinas/antagonistas & inibidores , Adalimumab/uso terapêutico , Doença de Crohn/tratamento farmacológico , Estudos Transversais , Humanos , Infliximab/uso terapêutico , Indução de Remissão , Resultado do Tratamento
20.
ACS Omega ; 6(24): 15637-15650, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34179608

RESUMO

Hydrogen (H2) has become one of the promising alternative clean energy resources. Membrane technology is a potential method for hydrogen separation or production. This study aims to develop a new carbon membrane for hydrogen separation or production. Moreover, the permeation behavior of H2, CO2, and CH4 through a hollow fiber composite carbon membrane derived from P84 co-polyimide and with incorporation of zeolite composite carbon (ZCC) was also examined. ZCC was synthesized via the impregnation method of sucrose into zeolite-Y pores, followed by carbonization at 800 °C. Thus, this filler has a high surface area, high microporosity, ordered pore structure, and low hydrophilicity. The presence of zeolites in ZCC is predicted to increase certain gases' affinity for the membrane. Various heating rates (1-5 °C/min) were applied during pyrolysis to understand the effect of the heating rate on the pore structure and H2/CO2 and H2/CH4 gas separation performance. Moreover, gas permeation was evaluated at various temperatures (298-373 K) to study the thermodynamic aspect of the process. A characteristic graphite peak was detected at 2θ ∼ 44° in all carbon samples. Scanning electron microscopy (SEM) observations revealed the void-free surface and the asymmetric structure of the carbon membranes. During the permeation test, it was found that gas permeation through the membrane was significantly affected by the temperature of the separation process. The highest permeability of H2, CO2, and CH4 was detected on the composite carbon membrane at a 3 °C/min heating rate with a permeation temperature of 373 K. The thermodynamic study shows that CO2 and H2 have lower activation energies compared to CH4. The transport mechanism of the membrane involved adsorption and activated surface diffusion. The permeation temperature has a large impact on the transport of small penetrants in the carbon matrix.

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