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1.
Clin Nucl Med ; 49(12): 1136-1138, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39485871

RESUMEN

ABSTRACT: Wild-type transthyretin amyloid (ATTRwt) deposits in most organs, mainly the heart, ligaments, and tenosynovium. Orthopedic diseases due to ATTRwt deposits often precede overt ATTRwt cardiomyopathy. 99mTc-PYP scintigraphy is highly sensitive in detecting myocardial and extracardiac ATTRwt deposits. However, there are few reports of extracardiac ATTRwt deposits before myocardial deposits confirmed by imaging modalities. We report a case of atrial fibrillation-related heart failure in which 99mTc-PYP scintigraphy showed tracer uptake in extracardiac soft tissues but not in the myocardium, and a biopsy of soft tissues with tracer uptake confirmed ATTRwt deposits. 99mTc-PYP scintigraphy can image extracardiac ATTRwt deposits before myocardial deposits.


Asunto(s)
Neuropatías Amiloides Familiares , Miocardio , Humanos , Neuropatías Amiloides Familiares/diagnóstico por imagen , Neuropatías Amiloides Familiares/metabolismo , Miocardio/metabolismo , Miocardio/patología , Masculino , Cintigrafía , Anciano , Pirofosfato de Tecnecio Tc 99m , Femenino , Transporte Biológico
2.
Clin Nucl Med ; 49(12): 1133-1135, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39480265

RESUMEN

ABSTRACT: Long-term subcutaneous insulin injection causes histopathological changes, such as insulin amyloidosis resulting in poor glycemic control, at the insulin injection site. Insulin amyloidosis often leads to the formation of a nodule called the "insulin ball." An insulin ball has not yet been documented on 99m Tc-PYP scintigraphy. Hereby, we describe the case of a 74-year-old man with insulin-requiring diabetes who developed heart failure with preserved ejection fraction due to new-onset atrial fibrillation. 99m Tc-PYP scintigraphy for cardiac amyloidosis screening showed no tracer uptake in the myocardium but did show uptake in the insulin ball suspected by CT and MRI scans.


Asunto(s)
Insulina , Humanos , Masculino , Anciano , Insulina/metabolismo , Transporte Biológico , Compuestos de Organotecnecio , Cintigrafía
3.
Chem Commun (Camb) ; 60(66): 8744-8747, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39072583

RESUMEN

G-quadruplex (G4) structures play roles in various biological processes, but the challenge lies in specific targeting. To address this, we synthesized a conjugate capable of recognizing the G4 structure and its proximal duplex. Our conjugate can enable recognition of specific G4s in the human genome to understand and target those structures.


Asunto(s)
ADN , G-Cuádruplex , ADN/química , Humanos , Genoma Humano , Sitios de Unión
4.
Clin Case Rep ; 12(6): e9022, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38855086

RESUMEN

Key Clinical Message: A whirl sign on contrast-enhanced abdominal CT scan is indicative of intestine twisted around the mesenteric vessels, and is observed in cases of strangulated obstruction, signaling compromised intestinal circulation. In cases of intestinal volvulus, surgery is necessary to untwist the affected bowel, and resection is necessary if necrosis is present. Abstract: A 31-year-old Japanese man presented with acute lower abdominal pain and vomiting. Contrast-enhanced abdominal computed tomography (CT) revealed a 1440-degree clockwise torsion of superior mesenteric artery and a whirl sign. Intestinal volvulus in adulthood with a background of malrotation is extremely rare. Contrast-enhanced CT is effective for diagnosis.

5.
Biochem Biophys Rep ; 38: 101712, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38903159

RESUMEN

Single-molecule intramolecular dynamics were successfully measured for three variants of SARS-CoV-2 spike protein, alpha: B.1.1.7, delta: B.1.617, and omicron: B.1.1.529, with a time resolution of 100 µs using X-rays. The results were then compared with respect to the magnitude and directions of motions for the three variants. The largest 3-D intramolecular movement was observed for the omicron variant irrespective of ACE2 receptor binding. A more detailed analysis of the intramolecular motions revealed that the distribution state of intramolecular motion for the three variants was completely different with and without ACE2 receptor binding. The molecular dynamics for the trimeric spike protein of the omicron variant increased when ACE2 binding occurred. At that time, the diffusion constant increased from 71.0 [mrad2/ms] to 91.1 [mrad2/ms].

6.
Commun Biol ; 7(1): 655, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38806706

RESUMEN

The gut microbiota influences human health and the development of chronic diseases. However, our understanding of potentially protective or harmful microbe-host interactions at the molecular level is still in its infancy. To gain further insights into the hidden gut metabolome and its impact, we identified a cryptic non-ribosomal peptide BGC in the genome of Bacillus cereus DSM 28590 from the mouse intestine ( www.dsmz.de/miBC ), which was predicted to encode a thiazol(in)e substructure. Cloning and heterologous expression of this BGC revealed that it produces bacillamide D. In-depth functional evaluation showed potent cytotoxicity and inhibition of cell migration using the human cell lines HCT116 and HEK293, which was validated using primary mouse organoids. This work establishes the bacillamides as selective cytotoxins from a bacterial gut isolate that affect mammalian cells. Our targeted structure-function-predictive approach is demonstrated to be a streamlined method to discover deleterious gut microbial metabolites with potential effects on human health.


Asunto(s)
Bacillus cereus , Microbioma Gastrointestinal , Bacillus cereus/metabolismo , Bacillus cereus/genética , Animales , Ratones , Humanos , Células HEK293 , Citotoxinas/metabolismo , Citotoxinas/genética , Células HCT116 , Intestinos/microbiología , Movimiento Celular , Organoides/metabolismo
7.
Proc Natl Acad Sci U S A ; 121(19): e2314704121, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38691589

RESUMEN

Amine modification through nucleophilic attack of the amine functionality is a very common chemical transformation. Under biorelevant conditions using acidic-to-neutral pH buffer, however, the nucleophilic reaction of alkyl amines (pKa ≈ 10) is not facile due to the generation of ammonium ions lacking nucleophilicity. Here, we disclose a unique molecular transformation system, catalysis driven by amyloid-substrate complex (CASL), that promotes amine modifications in acidic buffer. Ammonium ions attached to molecules with amyloid-binding capability were activated through deprotonation due to the close proximity to the amyloid catalyst formed by Ac-Asn-Phe-Gly-Ala-Ile-Leu-NH2 (NL6), derived from islet amyloid polypeptide (IAPP). Under the CASL conditions, alkyl amines underwent various modifications, i.e., acylation, arylation, cyclization, and alkylation, in acidic buffer. Crystallographic analysis and chemical modification studies of the amyloid catalysts suggested that the carbonyl oxygen of the Phe-Gly amide bond of NL6 plays a key role in activating the substrate amine by forming a hydrogen bond. Using CASL, selective conversion of substrates possessing equivalently reactive amine functionalities was achieved in catalytic reactions using amyloids. CASL provides a unique method for applying nucleophilic conversion reactions of amines in diverse fields of chemistry and biology.


Asunto(s)
Amiloide , Catálisis , Amiloide/química , Amiloide/metabolismo , Aminas/química , Aminas/metabolismo , Enlace de Hidrógeno , Polipéptido Amiloide de los Islotes Pancreáticos/química , Polipéptido Amiloide de los Islotes Pancreáticos/metabolismo , Concentración de Iones de Hidrógeno , Humanos
8.
J Med Virol ; 96(5): e29653, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38712746

RESUMEN

The magnitude of the effect of human T-lymphotropic virus 1 (HTLV-1) infection on uveitis remains unclear. We conducted a cross-sectional study in a highly endemic area of HTLV-1 in Japan. The study included 4265 residents (men, 39.2%), mostly middle-aged and older individuals with a mean age of 69.9 years, who participated in our surveys between April 2016 and September 2022. We identified HTLV-1 carriers by screening using chemiluminescent enzyme immunoassays and confirmatory tests, and the proportion of carriers was 16.1%. Participants with uveitis were determined from the medical records of all hospitals and clinics where certified ophthalmologists practiced. We conducted logistic regression analyses in an age- and sex-adjusted model to compute the odds ratio (OR) and 95% confidence interval (CI) of uveitis according to HTLV-1 infection status. Thirty-two (0.8%) participants had uveitis. For HTLV-1 carriers, the age- and sex-adjusted OR (95% CI) of uveitis was 3.27 (1.57-6.72) compared with noncarriers. In conclusion, HTLV-1 infection was associated with a higher risk of uveitis among mostly middle-aged and older Japanese residents in a highly endemic HTLV-1 area. Our findings suggest that physicians who treat HTLV-1 carriers should assess ocular symptoms, and those who diagnose patients with uveitis should consider HTLV-1 infection.


Asunto(s)
Portador Sano , Infecciones por HTLV-I , Virus Linfotrópico T Tipo 1 Humano , Uveítis , Humanos , Femenino , Masculino , Japón/epidemiología , Uveítis/epidemiología , Uveítis/virología , Infecciones por HTLV-I/epidemiología , Estudios Transversales , Anciano , Persona de Mediana Edad , Prevalencia , Virus Linfotrópico T Tipo 1 Humano/aislamiento & purificación , Portador Sano/epidemiología , Portador Sano/virología , Adulto , Anciano de 80 o más Años , Enfermedades Endémicas , Adulto Joven
9.
Clin Nucl Med ; 49(8): 767-770, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38651784

RESUMEN

ABSTRACT: 99m Tc-3,3-diphosphono-1,2-propanedicarboxylic acid (DPD) scintigraphy and 99m Tc-pyrophosphate (PYP) scintigraphy are highly sensitive modalities for imaging both myocardial and extracardiac amyloid transthyretin in patients with wild-type transthyretin (ATTRwt) amyloidosis. "Loss of bone signal" on planar imaging of 99m Tc-DPD scintigraphy, in which the tracer uptake in bone is obscured by marked tracer uptake in the overlying skeletal muscles, is reported. However, this phenomenon has not yet been documented on 99m Tc-PYP scintigraphy. We describe an 89-year-old woman with ATTRwt amyloidosis in whom "loss of bone signal" together with marked tracer uptake into the skeletal muscles was clearly demonstrated on 99m Tc-PYP scan.


Asunto(s)
Neuropatías Amiloides Familiares , Huesos , Cintigrafía , Pirofosfato de Tecnecio Tc 99m , Humanos , Femenino , Anciano de 80 o más Años , Neuropatías Amiloides Familiares/diagnóstico por imagen , Huesos/diagnóstico por imagen , Prealbúmina/metabolismo
10.
Membranes (Basel) ; 14(4)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38668103

RESUMEN

Protein dynamics play important roles in biological functions, which accompany allosteric structure changes. Diffracted X-ray blinking (DXB) uses monochromatic X-rays and nanocrystal probes. The intramolecular motion of target proteins is analyzed from the intensity changes in detector signals at the diffraction rings. In contrast, diffracted X-ray tracking (DXT) elucidates molecular dynamics by analyzing the trajectories of Laue spots. In this study, we have developed a dual-labeling technique for DXB and DXT, allowing the simultaneous observation of motions at different domains in proteins. We identified zinc oxide (ZnO) crystals as promising candidates for the second labeling probes due to their excellent diffraction patterns, high chemical stability, and favorable binding properties with proteins. The diffraction spots from the ZnO crystals are sufficiently separated from those of gold, enabling independent motion analysis at different domains. Dual-labeling DXB was employed for the motion analysis of the 5-HT2A receptor in living cells. Simultaneous motion recording of the N-terminus and the second extracellular loop demonstrated ligand-induced motion suppression at both domains. The dual-labeling DXT technique demonstrated a capsaicin-induced peak shift in the two-dimensional motion maps at the N-terminus of the TRPV1 protein, but the peak shift was not obvious in the C-terminus. The capsaicin-induced motion modulation was recovered by the addition of the competitive inhibitor AMG9810.

11.
J Nanobiotechnology ; 22(1): 114, 2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38493106

RESUMEN

BACKGROUND: Rice bran a by-product of the rice milling process is currently underutilized. Recent studies have shown that plant-derived nanoparticles (pdNPs) can be mass-produced at a low cost and exhibit biological and therapeutic activities. Rice bran contains various anti-cancer compounds, including γ-oryzanol and γ-tocotrienol, and rice bran-derived nanoparticles (rbNPs) can be employed as novel therapeutic agents for cancer treatment. RESULTS: Koshihikari rice bran was suspended in water, and the suspension was centrifuged and filtered through a 0.45-µm-pore size syringe filter. The filtrate was ultracentrifuged, and the precipitates were suspended to obtain rbNPs. The rbNPs were negatively charged exosome-like nanoparticles with an average diameter of approximately 130 nm. The rbNPs exhibited cytotoxic activities against cancer cells but not against normal cells. The cytotoxic activity of rbNPs to murine colon adenocarcinoma colon26 cells was significantly greater than DOXIL® or other pdNPs. The rbNPs induced cell cycle arrest and apoptosis, and reduced the expression of proliferative proteins, including ß-catenin and cyclin D1. Intraperitoneal injections of rbNPs into mice bearing peritoneal dissemination of colon26 cells significantly suppressed tumor growth with no significant adverse effects. CONCLUSION: These results indicated that rbNPs are promising nanoparticles, hold significant potential for anti-cancer applications, and are expected to play a vital role in cancer treatment.


Asunto(s)
Adenocarcinoma , Antineoplásicos , Neoplasias del Colon , Oryza , Animales , Ratones , Neoplasias del Colon/tratamiento farmacológico , Antioxidantes/farmacología , Antineoplásicos/farmacología
12.
Environ Microbiol Rep ; 16(2): e13243, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38425145

RESUMEN

We developed a simulation model of human oral microbiota using Bio Palette oral medium (BPOM) containing 0.02% glucose and lower bacterial nitrogen sources, derived from saliva and dental plaque. By decreasing the concentration of Gifu anaerobic medium (GAM) from 30 to 10 g L-1 , we observed increased ratios of target pathogenic genera, Porphyromonas and Fusobacterium from 0.5% and 1.7% to 1.2% and 3.5%, respectively, in the biofilm on hydroxyapatite (HA) discs. BPOM exhibited the higher ratios of Porphyromonas and Fusobacterium, and amplicon sequence variant number on HA, compared with GAM, modified GAM and basal medium mucin. Mixing glycerol stocks of BPOM culture solutions from four human subjects resulted in comparable ratios of these bacteria to the original saliva. In this simulation model, sitafloxacin showed higher inhibitory effects on P. gingivalis than minocycline hydrochloride at a low dosage of 0.1 µg mL-1 . Probiotics such as Streptococcus salivarius and Limosilactobacillus fermentum also showed significant decreases in Porphyromonas and Fusobacterium ratios on HA, respectively. Overall, the study suggests that BPOM with low carbon and nutrients could be a versatile platform for assessing the efficacy of antibiotics and live biotherapeutics in treating oral diseases caused by Porphyromonas and Fusobacterium.


Asunto(s)
Fusobacterium nucleatum , Microbiota , Humanos , Porphyromonas gingivalis/genética , Saliva/microbiología , Biopelículas
13.
Sci Rep ; 14(1): 2649, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302478

RESUMEN

"Yips" are involuntary movements that interfere with the automatic execution of sports movements. However, how the coordination among the various muscles necessary for sports movements is impaired in athletes with yips remains to be fully understood. This study aimed to assess whether muscle synergy analysis through non-negative matrix factorization (NMF) could identify impaired spatiotemporal muscle coordination in baseball players with throwing yips. Twenty-two college baseball players, including 12 with and 10 without yips symptoms participated in the study. Electromyographic activity was recorded from 13 ipsilateral upper extremity muscles during full-effort throwing. Muscle synergies were extracted through NMF. Cluster analysis was conducted to identify any common spatiotemporal patterns of muscle synergies in players with yips. Whether individual players with yips showed deviations in spatiotemporal patterns of muscle synergies compared with control players was also investigated. Four muscle synergies were extracted for each player, but none were specific to the yips group. However, a more detailed analysis of individual players revealed that two of the three players who presented dystonic symptoms during the experiment exhibited specific patterns that differed from those in control players. By contrast, each player whose symptoms were not reproduced during the experiment presented spatiotemporal patterns of muscle synergies similar to those of the control group. The results of this study indicate no common spatiotemporal pattern of muscle synergies specific to the yips group. Furthermore, these results suggest that the spatiotemporal pattern of muscle synergies in baseball throwing motion is not impaired in situations where symptoms are not reproduced even if the players have yips symptoms. However, muscle synergy analysis can identify the characteristics of muscle coordination of players who exhibit dystonic movements. These findings can be useful in developing personalized therapeutic strategies based on individual characteristics of yips symptoms.


Asunto(s)
Béisbol , Deportes , Humanos , Béisbol/fisiología , Deportes/fisiología , Músculo Esquelético , Movimiento , Extremidad Superior
14.
Eur Biophys J ; 53(1-2): 15-25, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38233601

RESUMEN

The α7 nicotinic acetylcholine receptor is a member of the nicotinic acetylcholine receptor family and is composed of five α7 subunits arranged symmetrically around a central pore. It is localized in the central nervous system and immune cells and could be a target for treating Alzheimer's disease and schizophrenia. Acetylcholine is a ligand that opens the channel, although prolonged application rapidly decreases the response. Ivermectin was reported as one of the positive allosteric modulators, since the binding of Ivermectin to the channel enhances acetylcholine-evoked α7 currents. One research has suggested that tilting motions of the nicotinic acetylcholine receptor are responsible for channel opening and activation. To verify this hypothesis applies to α7 nicotinic acetylcholine receptor, we utilized a diffracted X-ray tracking method to monitor the stable twisting and tilting motion of nAChR α7 without a ligand, with acetylcholine, with Ivermectin, and with both of them. The results show that the α7 nicotinic acetylcholine receptor twists counterclockwise with the channel transiently opening, transitioning to a desensitized state in the presence of acetylcholine and clockwise without the channel opening in the presence of Ivermectin. We propose that the conformational transition of ACh-bound nAChR α7 may be due to the collective twisting of the five α7 subunits, resulting in the compression and movement, either downward or upward, of one or more subunits, thus manifesting tilting motions. These tilting motions possibly represent the transition from the resting state to channel opening and potentially to the desensitized state.


Asunto(s)
Receptores Nicotínicos , Receptor Nicotínico de Acetilcolina alfa 7 , Receptor Nicotínico de Acetilcolina alfa 7/química , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo , Acetilcolina/química , Acetilcolina/metabolismo , Ligandos , Ivermectina/farmacología , Receptores Nicotínicos/química , Receptores Nicotínicos/metabolismo , Regulación Alostérica
15.
J Control Release ; 367: 486-499, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38295995

RESUMEN

Cell transplantation is a promising therapeutic strategy for myocardial regeneration therapy. To improve therapeutic effects, we developed a culture medium additive that enhances the mitochondrial function of cardiomyocytes for transplantation. A mitochondrial targeting drug delivery system (MITO-Porter system) was used to deliver mitochondrial activation molecules to mouse-derived cardiac progenitor cells. In this study, we investigated whether the mitochondrial function of human-derived myocardial precursor cells could be enhanced using MITO-Porter. Human cardiosphere-derived cells (CDCs) were isolated from myocardium which was excised during surgery for congenital heart disease. MITO-Porter was added to the cell culture medium to generate mitochondrial activated CDCs (human MITO cells). The human MITO cells were transplanted into myocardial ischemia-reperfusion model rat, and the effect was investigated. The transplanted human MITO cells improved the cardiac function and suppressed myocardial fibrosis compared to conventional cell transplantation methods. These effects were observed not only with myocardial administration but also by intravenous administration of human MITO cells. This study is the first study that assessed whether the mitochondrial delivery of functional compounds improved the outcome of human-derived myocardial cell transplantation therapy.


Asunto(s)
Cardiomiopatías , Miocardio , Ratones , Humanos , Ratas , Animales , Miocardio/metabolismo , Miocitos Cardíacos , Sistemas de Liberación de Medicamentos , Mitocondrias , Cardiomiopatías/metabolismo
16.
Amyloid ; 31(1): 12-21, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37486102

RESUMEN

BACKGROUND: Technetium-99m-pyrophosphate (99mTc-PYP) uptake in the internal oblique muscle (IOM), which is often observed in patients with wild-type transthyretin cardiac amyloidosis (ATTR-CA), indicates amyloid transthyretin (ATTR) deposition. OBJECTIVE: This study aimed to assess the safety and efficacy of 99mTc-PYP imaging-based computed tomography (CT)-guided core-needle biopsy of the IOM as a new extracardiac screening biopsy for confirming the presence of ATTR deposits. METHODS: Patients with suspected ATTR-CA in whom myocardial tracer uptake was detected on chest- and abdomen-centered images of 99mTc-PYP scintigraphy underwent CT-guided core-needle biopsy at the site with the highest tracer uptake in the IOM between September 2021 and November 2022. RESULTS: All 18 consecutive patients (mean age, 86.3 years ± 6.5; 61.1% male) enrolled in the study showed 99mTc-PYP uptake into the IOM. Adequate tissue samples were obtained from all patients except one without serious complications. Immunohistochemical analysis confirmed ATTR deposits in 16/18 (88.9%) patients. In the remaining two patients, ATTR deposits were observed via endomyocardial biopsy. All patients were diagnosed with wild-type ATTR-CA based on transthyretin gene sequence testing results. CONCLUSION: In wild-type ATTR-CA, 99mTc-PYP imaging-based CT-guided core-needle biopsy of the IOM could be used as an extracardiac screening biopsy to confirm the presence of ATTR deposits.


Asunto(s)
Amiloidosis , Cardiomiopatías , Humanos , Masculino , Anciano de 80 o más Años , Femenino , Pirofosfato de Tecnecio Tc 99m , Difosfatos , Tecnecio , Prealbúmina/genética , Músculos Oblicuos del Abdomen , Amiloidosis/genética , Tomografía Computarizada por Rayos X , Biopsia , Biopsia con Aguja , Cardiomiopatías/diagnóstico por imagen , Radiofármacos
18.
Virus Res ; 339: 199294, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38056502

RESUMEN

Saliva is a key component of mucosal immunity, which protects the oral cavity from viral infections. However, salivary immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in terms of immunoglobulin dynamics and recognition, have not been investigated sufficiently. In this study, saliva samples were collected from individuals that received SARS-CoV-2 vaccine, and immunoglobulin G (IgG), IgM, and IgA against whole spike protein and S1 protein were measured. IgA against whole spike protein increased significantly following vaccination, while IgA against S1 protein did not. Of note, the IgA response was evident two weeks after the first vaccine dose and continued to rise thereafter. On the contrary, IgG antibodies against S1 increased significantly at four weeks after vaccination. These results reveal the dynamics and recognition antigens of immunoglobulins in saliva, indicating the function of IgA in the mucosal immune system. These findings may pave the way for further studies on mucosal immune response induced by vaccination.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Humanos , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , COVID-19/prevención & control , Vacunación , Inmunoglobulina G , Inmunoglobulina A , Anticuerpos Antivirales
19.
Int J Mol Sci ; 24(24)2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38139291

RESUMEN

The photoinduced crawling motion of crystals is a continuous motion that azobenzene molecular crystals exhibit under light irradiation. Such motion enables object manipulation at the microscale with a simple setup of fixed LED light sources. Transportation of nano-/micromaterials using photoinduced crawling motion has recently been reported. However, the details of the motion mechanism have not been revealed so far. Herein, we report visualization of the dynamics of fine particles in 4-(methylamino)azobenzene (4-MAAB) crystals under light irradiation via diffracted X-ray tracking (DXT). Continuously repeated melting and recrystallization of 4-MAAB crystals under light irradiation results in the flow of liquid 4-MAAB. Zinc oxide (ZnO) particles were introduced inside the 4-MAAB crystals to detect diffracted X-rays. The ZnO particles rotate with the flow of liquid 4-MAAB. By using white X-rays with a wide energy width, the rotation of each zinc oxide nanoparticle was detected as the movement of a bright spot in the X-ray diffraction pattern. It was clearly shown that the ZnO particles rotated increasingly as the irradiation light intensity increased. Furthermore, we also found anisotropy in the rotational direction of ZnO particles that occurred during the crawling motion of 4-MAAB crystals. It has become clear that the flow perpendicular to the supporting film of 4-MAAB crystals is enhanced inside the crystal during the crawling motion. DXT provides a unique means to elucidate the mechanism of photoinduced crawling motion of crystals.


Asunto(s)
Óxido de Zinc , Rayos X , Compuestos Azo/química , Rotación
20.
Microbiol Spectr ; 11(6): e0207823, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37966220

RESUMEN

IMPORTANCE: The World Health Organization estimated that 5-10 million people are infected with human T-cell leukemia virus type 1 (HTLV-1). This number is likely to be underestimated because reliable endemic data are available for only approximately 1.5 billion people worldwide. The point-of-care test is a powerful tool for the easy and quick detection of infections without the requirement for expensive instruments and laboratory equipment. Espline HTLV-I/II, a newly developed rapid immunochromatographic antibody test that was evaluated in this study, might significantly advance our understanding of the global epidemiology of HTLV-1 infection.


Asunto(s)
Infecciones por HTLV-I , Virus Linfotrópico T Tipo 1 Humano , Humanos , Infecciones por HTLV-I/diagnóstico , Infecciones por HTLV-I/epidemiología
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