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1.
Antiviral Res ; 223: 105819, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272319

RESUMO

HIV-associated lipodystrophy has been reported in people taking anti-retroviral therapy (ART). Lipodystrophy can cause cardiovascular diseases, affecting the quality of life of HIV-infected individuals. In this study, we propose a pharmacological lipid index to estimate the risk of hyperlipidemia caused by anti-retroviral drugs. Lipid droplets were stained in cells treated with anti-retroviral drugs and cyclosporin A. Signal intensities of lipid droplets were plotted against the drug concentrations to obtain an isodose of 10 µM of cyclosporin A, which we call the Pharmacological Lipid Index (PLI). The PLI was then normalized by EC50. PLI/EC50 values were low in early proteinase inhibitors and the nucleoside reverse transcriptase inhibitor, d4T, indicating high risk of hyperlipidemia, which is consistent with previous findings of hyperlipidemia. In contrast, there are few reports of hyperlipidemia for drugs with high PLI/EC50 scores. Data suggests that PLI/EC50 is a useful index for estimating the risk of hyperlipidemia.


Assuntos
Doenças Cardiovasculares , Hiperlipidemias , Humanos , Hiperlipidemias/induzido quimicamente , Ciclosporina , Qualidade de Vida , Lipídeos
2.
Pancreas ; 53(1): e49-e54, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38019197

RESUMO

OBJECTIVE: This study aimed to investigate whether a novel, easy loop-forming guidewire could reduce post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) in patients undergoing endoscopic nasopancreatic drainage tube placement for serial pancreatic juice aspiration cytologic examination (SPACE). METHODS: We evaluated patients with suspected pancreatic cancer who underwent SPACE at our institution between January 2015 and April 2023 retrospectively. The patients were divided into 2 groups based on the type of guidewire used, namely, easy loop-forming and control groups. Propensity score matching was used to compare the incidence of PEP between the groups. RESULTS: We included 101 patients, with 51 and 50 in the easy loop-forming and control groups, respectively. After propensity score matching, 29 pairs of patients were selected from each group. Intraductal ultrasonography of the pancreas was performed more frequently in the easy loop-forming group than in the control group (27.6% vs 0%; P = 0.004); however, PEP incidence was significantly lower in the easy loop-forming group than in the control group (3.4% vs 27.6%; odds ratio, 0.097; 95% confidence interval, 0.002-0.82; P = 0.025). CONCLUSIONS: The use of the novel easy loop-forming guidewire decreased PEP occurrence in patients who underwent endoscopic nasopancreatic drainage tube placement for SPACE.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Pancreatite , Humanos , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Suco Pancreático , Pontuação de Propensão , Estudos Retrospectivos , Ductos Pancreáticos , Pancreatite/diagnóstico , Pancreatite/etiologia , Pancreatite/prevenção & controle , Fatores de Risco
3.
Cureus ; 15(11): e48468, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38074013

RESUMO

We present the case of a 72-year-old woman with elevated hepatobiliary enzymes and a small mass in the distal bile duct near the papilla. Fluoroscopy-guided forceps biopsy initially yielded insufficient tissue. After endoscopic papillary large balloon dilation with sphincterotomy, a stone retrieval balloon was used to expose the tumor to the duodenum. Biopsy under direct visualization using standard forceps revealed adenocarcinoma. The technique may be useful for the biopsy of lesions located in the terminal segment of the distal bile duct.

4.
Phys Rev Lett ; 131(16): 163201, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37925726

RESUMO

X-ray diffraction of silicon irradiated with tightly focused femtosecond x-ray pulses (photon energy, 11.5 keV; pulse duration, 6 fs) was measured at various x-ray intensities up to 4.6×10^{19} W/cm^{2}. The measurement reveals that the diffraction intensity is highly suppressed when the x-ray intensity reaches of the order of 10^{19} W/cm^{2}. With a dedicated simulation, we confirm that the observed reduction of the diffraction intensity can be attributed to the femtosecond change in individual atomic scattering factors due to the ultrafast creation of highly ionized atoms through photoionization, Auger decay, and subsequent collisional ionization. We anticipate that this ultrafast reduction of atomic scattering factor will be a basis for new x-ray nonlinear techniques, such as pulse shortening and contrast variation x-ray scattering.

5.
J Chem Ecol ; 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37882872

RESUMO

Toxic organisms can become food that potentially harms consumers. When these organisms become invasive species, the harm often turns to a serious threat that disrupts native ecosystems. On the other hand, there are consumers that can exploit toxic organisms for food and sequester intact toxins from them for the consumers' own chemical defense. Therefore, it can be expected that toxic invasive prey can become a toxin source for native consumers. Here, we focused on the relationship between toads, which are one of the major toxic invasive organisms and possess bufadienolides (BDs), and Rhabdophis snakes, which sequester BDs from toads. On Sado Island, Japan, R. tigrinus is native, but no toads had inhabited this island until Bufo japonicus formosus was introduced as a domestic invasive species in 1963 and 1964. At present, invasive toads are distributed only in the southwestern part of the island. We collected a total of 25 and 24 R. tigrinus from areas allopatric and sympatric with toads, respectively. Then, we investigated the possession of BDs and the BD profile of these snakes. We found that only R. tigrinus sympatric with toads possessed BDs, whereas all snakes allopatric with toads lacked BDs. Based on the characteristics of the BD profile, the toxin source was identified as B. j. formosus. Our findings show that a new case of impact caused by toxic invasive species, i.e., "toxin supply to native consumers from invasive prey", could occur.

6.
Opt Express ; 31(16): 26135-26144, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710481

RESUMO

We demonstrate a propagation-based phase-contrast imaging method for full-field X-ray microscopy based on advanced Kirkpatrick-Baez (AKB) mirrors to achieve high-contrast observations of weak phase objects and correct field curvature aberrations. Through a demonstration performed at SPring-8, the phase contrast of weak phase objects such as polystyrene spheres and chemically fixed cells was successfully observed with high sensitivity (∼0.03 rad). Furthermore, the field of view of the AKB mirrors was expanded to the full area of the obtained images (25 × 30 µm) by correcting the field curvature aberration using reconstructed complex wavefields.

8.
J Chem Ecol ; 49(3-4): 133-141, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36881327

RESUMO

The snake Rhabdophis tigrinus sequesters cardiotonic steroids, bufadienolides (BDs), from ingested toads and stores them in the nuchal glands as defensive toxins. It has previously been shown that there are individual differences in the total quantity of BDs stored in the nuchal glands of adult R. tigrinus and that BD quantities and profiles of R. tigrinus exhibit geographic variation. However, no previous study has examined the total quantity of BDs as a percentage of body mass (relative BD quantity) and the concentration of BDs in the nuchal gland fluid (BD gland concentration). In addition, intrinsic factors that are associated with relative BD quantity and BD concentration have not been examined within a single population. We collected 158 adult snakes from an area of central Japan from May to October and analyzed their BD quantities by UV analysis. We assessed individual differences in BD quantity, relative BD quantity and BD gland concentration. We found that 1) in approximately 60% of the 158 individuals, the BD gland concentration was greater than 50%; 2) body length and body condition are positively correlated with relative BD quantity and BD gland concentration; 3) even in a single population, individual differences of BD quantity are large, and are greater in females than in males; and 4) relative BD quantity and BD gland concentration of females during the gestation season are lower than those during the non-gestation season.


Assuntos
Bufanolídeos , Colubridae , Toxinas Biológicas , Humanos , Masculino , Animais , Feminino , Adulto , Bufonidae , Japão
9.
Sci Rep ; 13(1): 3484, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36922503

RESUMO

Metal homeostasis is tightly regulated in cells and organisms, and its disturbance is frequently observed in some diseases such as neurodegenerative diseases and metabolic disorders. Previous studies suggest that zinc and iron are necessary for the normal functions of pancreatic ß cells. However, the distribution of elements in normal conditions and the pathophysiological significance of dysregulated elements in the islet in diabetic conditions have remained unclear. In this study, to investigate the dynamics of elements in the pancreatic islets of a diabetic mouse model expressing human islet amyloid polypeptide (hIAPP): hIAPP transgenic (hIAPP-Tg) mice, we performed imaging analysis of elements using synchrotron scanning X-ray fluorescence microscopy and quantitative analysis of elements using inductively coupled plasma mass spectrometry. We found that in the islets, zinc significantly decreased in the early stage of diabetes, while iron gradually decreased concurrently with the increase in blood glucose levels of hIAPP-Tg mice. Notably, when zinc and/or iron were decreased in the islets of hIAPP-Tg mice, dysregulation of glucose-stimulated mitochondrial respiration was observed. Our findings may contribute to clarifying the roles of zinc and iron in islet functions under pathophysiological diabetic conditions.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Ilhotas Pancreáticas , Humanos , Camundongos , Animais , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Zinco/metabolismo , Ferro/metabolismo , Camundongos Transgênicos , Amiloide/metabolismo , Ilhotas Pancreáticas/metabolismo , Células Secretoras de Insulina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo
11.
Chem Biol Interact ; 369: 110257, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36375514

RESUMO

Compounds with 3,4-fused tricyclic indole (FTI) frameworks are attractive scaffolds for drug discovery. We synthesized FTI-6D, a compound with this framework, which was cytotoxic in several human cancer cell lines. FTI-6D induced apoptosis via activation of the p53 downstream mitochondria-related apoptotic pathway, characterized by an increased ratio of pro-apoptotic Bcl-2 family members to anti-apoptotic members. This change was followed by caspase-9 and caspase-3 cleavage and activation in two cancer cell lines, RKO and AGS. The anti-proliferating effect of FTI-6D was remarkably detected in eight cancer cells with wild-type TP53 (TP53_wt), including RKO and AGS, but not in seven cancer cells with mutated TP53 (TP53_mut). Additionally, p53 protein levels increased after FTI-6D treatment in TP53_wt cancer cells, and the cytotoxic effect of FTI-6D was decreased by TP53 knockdown. Accordingly, the expression of p53 downstream genes involved in apoptotic signaling pathways, such as BBC3 and TP53INP1, and those involved in cell growth inhibition, such as CDKN1A, was upregulated in TP53_wt cancer cells. These results suggest that the anti-proliferative and apoptosis-inducing activities of FTI-6D rely on p53 and the corresponding signaling processes. This study demonstrated that FTI-6D shows anti-cancer activity against TP53_wt cancer cells. FTI-6D may have potential as a prototype compound for a new drug to utilize a functional p53 pathway in TP53_wt cancer cells.


Assuntos
Neoplasias , Proteína Supressora de Tumor p53 , Humanos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Genes p53 , Apoptose , Linhagem Celular Tumoral , Células HCT116 , Neoplasias/genética , Proteínas de Transporte/genética , Proteínas de Choque Térmico/metabolismo
12.
Surg Endosc ; 37(5): 3449-3454, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36550312

RESUMO

BACKGROUND: Techniques and devices for endoscopic ultrasound (EUS)-guided hepaticoenterostomy (EUS-HES) procedures, including EUS-guided hepaticogastrostomy (EUS-HGS) and EUS-guided hepaticojejunostomy (EUS-HJS), have been developed; however, the optimal timing to begin oral intake after EUS-HES remains unknown. This study aimed to evaluate the safety of early oral intake after EUS-HES. METHODS: We retrospectively investigated patients who underwent EUS-HES (EUS-HGS or EUS-HJS) between March 2015 and March 2022. Patients who had no problems with the results of blood tests and computed tomography examinations on the morning of day 1 after EUS-HES were classified as either the early intake group (started oral intake on day 1 after EUS-HES) or the late intake group (started oral intake on day 2 or later after EUS-HES). Patients' characteristics, procedure characteristics, and early postprocedural adverse events (within 14 days after the procedure) were compared between groups. RESULTS: Fifty patients were enrolled in this study. Forty-three patients had no problems with the results of examinations performed on the morning of day 1 after EUS-HES. Twenty-one patients comprised the early intake group and 22 comprised the late intake group. Adverse events that developed within 14 days after EUS-HES were not significantly different between groups (early 4.7% vs. late 9.0%; odds ratio, 0.50; 95% confidence interval, 0.0080-10.49; P = 1.00). CONCLUSIONS: Starting oral intake on day 1 after EUS-HES did not increase postprocedural adverse events compared with starting oral intake on day 2 or later after EUS-HES.


Assuntos
Colestase , Stents , Humanos , Estudos Retrospectivos , Portoenterostomia Hepática , Anastomose Cirúrgica , Endossonografia/métodos , Ultrassonografia de Intervenção , Drenagem/métodos , Colestase/cirurgia
13.
Oxf Med Case Reports ; 2022(9): omac096, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36176948

RESUMO

We report the case of diffuse large B-cell lymphoma (DLBCL) with a fistula from the ileum to the cecum. A 57-year-old male came to the hospital complaining of abdominal pain. He underwent an abdominal computed tomography with contrast, which showed full-thickness wall thickening at the ileocecal region. He underwent a lower gastrointestinal endoscopy. No tumor was found at the ileocecal valve, and macroscopic findings were normal. The scope was advanced to the cecum, an additional outpouching was found. The outpouching appeared to be an ileocecal fistula. The diagnosis was DLBCL.

14.
J Hepatobiliary Pancreat Sci ; 29(8): e77-e78, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35384337

RESUMO

Conventional gallbladder re-intervention along the naso-gallbladder drainage tube may result in dislocation of the tube during scope insertion or failure of guidewire insertion into the gallbladder. Mandai et al report a simple method for transferring a transpapillary naso-gallbladder drainage tube to the mouth that facilitates reliable re-intervention for gallbladder lesions.


Assuntos
Drenagem , Vesícula Biliar , Colangiopancreatografia Retrógrada Endoscópica , Humanos , Boca
16.
Appl Opt ; 61(35): 10465-10470, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36607107

RESUMO

A field-curvature-corrected imaging optical system for x-ray microscopy using only grazing-incidence mirrors is proposed. It combines a Wolter type I (WO1) mirror pair, which forms a real image, with field curvature correction (FCC) optics-a convex hyperbolic mirror pair-that form a virtual image; compensation of the field curvatures realizes a wide field-of-view (FOV) and high magnification. Ray-tracing and wave-optics simulations verified the efficacy of the design, for which a FOV width was 111 µm-4.7 times larger than that for the uncorrected WO1 design. The addition of FCC optics also produced a 2.3-fold increase in magnification.

17.
Curr Zool ; 68(6): 627-634, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36743225

RESUMO

Several Asian natricine snakes of the genus Rhabdophis feed on toads and sequester steroidal cardiac toxins known as bufadienolides (BDs) from them. A recent study revealed that species of the Rhabdophis nuchalis Group ingest lampyrine fireflies to sequester BDs. Although several species of fireflies are distributed in the habitat of the R. nuchalis Group, only lampyrine fireflies, which have BDs, are included in the diet of these snakes. Thus, we hypothesized that the R. nuchalis Group chemically distinguishes fireflies that have BDs from those that do not have BDs. We also predicted that the R. nuchalis Group detects BDs as the chemical cue of toxin source. To test these predictions, we conducted 3 behavioral experiments using Rhabdophis chiwen, which belongs to the R. nuchalis Group. In the first experiment, R. chiwen showed a moderate tongue flicking response to cinobufagin, a compound of BDs. On the other hand, the snake showed a higher response to the chemical stimuli of lampyrine fireflies (BD fireflies) than those of lucioline fireflies (non-BD fireflies). In the second experiment, in which we provided live BD and non-BD fireflies, the snake voluntarily consumed only the former. In the third, a Y-maze experiment, the snake tended to select the chemical trail of BD fireflies more frequently than that of non-BD fireflies. These results demonstrated that R. chiwen discriminates BD fireflies from non-BD fireflies, but the prediction that BDs are involved in this discrimination was not fully supported. To identify the proximate mechanisms of the recognition of novel toxic prey in the R. nuchalis Group, further investigation is necessary.

18.
Chem Res Toxicol ; 34(12): 2471-2484, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34841876

RESUMO

It is widely recognized that the toxicity of mercury (Hg) is attenuated by the simultaneous administration of selenium (Se) compounds in various organisms. In this study, we revealed the mechanisms underlying the antagonistic effect of sodium selenite (Na2SeO3) on inorganic Hg (Hg2+) toxicity in human hepatoma HepG2 cells. Observations by transmission electron microscopy indicated that HgSe (tiemannite) granules of up to 100 nm in diameter were accumulated in lysosomal-like structures in the cells. The HgSe granules were composed of a number of HgSe nanoparticles, each measuring less than 10 nm in diameter. No accumulation of HgSe nanoparticles in lysosomes was observed in the cells exposed to chemically synthesized HgSe nanoparticles. This suggests that intracellular HgSe nanoparticles were biologically generated from Na2SeO3 and Hg2+ ions transported into the cells and were not derived from HgSe nanoparticles formed in the extracellular fluid. Approximately 85% of biogenic HgSe remained in the cells at 72 h post culturing, indicating that biogenic HgSe was hardly excreted from the cells. Moreover, the cytotoxicity of Hg2+ was ameliorated by the simultaneous exposure to Na2SeO3 even before the formation of insoluble HgSe nanoparticles. Our data confirmed for the first time that HepG2 cells can circumvent the toxicity of Hg2+ through the direct interaction of Hg2+ with a reduced form of Se (selenide) to form HgSe nanoparticles via a Hg-Se soluble complex in the cells. Biogenic HgSe nanoparticles are considered the ultimate metabolite in the Hg detoxification process.


Assuntos
Mercúrio/efeitos adversos , Nanopartículas/efeitos adversos , Selênio/efeitos adversos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Mercúrio/metabolismo , Nanopartículas/metabolismo , Selênio/metabolismo , Células Tumorais Cultivadas
19.
IUCrJ ; 8(Pt 5): 713-718, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34584733

RESUMO

X-ray scientists are continually striving to improve the quality of X-ray microscopy, due to the fact that the information obtained from X-ray microscopy of materials can be complementary to that obtained from optical and electron microscopes. In contrast to the ease with which one can deflect electron beams, the relative difficulty to deflect X-ray has constrained the development of scanning X-ray microscopes (SXMs) based on a scan of an X-ray small probe. This restriction has caused severe complications that hinder progress toward achieving ultimate resolution. Here, a simple and innovative method for constructing an SXM equipped with a nanoprobe scanner is proposed. The nanoprobe scanner combines X-ray prisms and advanced Kirkpatrick-Baez focusing mirrors. By rotating the prisms on the order of degrees, X-ray probe scanning with single-nanometre accuracy can be easily achieved. The validity of the concept was verified by acquiring an SXM image of a test pattern at a photon energy of 10 keV, where 50 nm line-and-space structures were resolved. This method is readily applicable to an SXM with a single-nanometre resolution and will assist effective utilization of increasing brightness of fourth-generation synchrotron radiation sources.

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