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1.
Acta Psychol (Amst) ; 241: 104096, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38041914

RESUMO

Managers have been applying the influence of herd behaviour to stimulate purchase intention but have not achieved precise results because they do not clearly understand the mechanism of this relationship. This article aims to determine the effect of herd behaviour on the relationship between information adoption and purchase intention and the moderating of risk aversion. With 17 variables for four concepts, data was collected online with 340 respondents and analysed with a partial least squares structural equation modelling. When considering herd behaviour in terms of subjective norms with corroborated information, this study upgrades the classic role of the theory of planned behaviour in purchase intention. The findings indicate a positive relationship between herd behaviour, information adoption and purchase intention. In particular, risk aversion is a positive moderator of the relationship between herd behaviour and purchase intention. This result is a significant addition to the theoretical body and shows that risk aversion can drive purchase intention through herd behaviour. In other words, this study upgrades the perception of information source authentication through herd behaviour to explain the purchase intentions of Vietnamese consumers. These results show that managers can create risky situations to promote herd behaviour. They can also apply information adoption stimuli to stimulate herd behaviour. At the same time, through the information adoption mechanism, consumers can be more alert to the effect of herd behaviour and have more opinions when making purchases.


Assuntos
Atitude , Intenção , Humanos , Vietnã , Comportamento do Consumidor
2.
Acta Radiol ; 64(2): 675-683, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35437022

RESUMO

BACKGROUND: Carpal tunnel syndrome (CTS) is the most common type of peripheral nerve compression. Magnetic resonance imaging (MRI) is becoming more popular in practice in the evaluation of CTS. PURPOSE: To evaluate the diagnostic value of MRI in CTS. MATERIAL AND METHODS: A cross-sectional study of 39 wrists was conducted. Clinical and nerve conduction study findings were evaluated and graded according to the Boston Carpal Tunnel Questionnaire (BCTQ) and the American Association of Neuromuscular and Electrodiagnostic Medicine. MRI was performed using a 1.5-T scanner. MRI parameters included cross-sectional area (CSA) of the median nerve and the ratio change in CSA at four levels: distal radioulnar joint (DRUJ-CSA); pisiform (p-CSA); middle of the carpal tunnel (i-CSA); and hook of hamate. The ratio change in CSA was expressed as p-CSA/DRUJ-CSA and ΔCSA (difference between iCSA and DRUJ-CSA), the flattening ratio of the median nerve, the thickness of the flexor retinaculum, flexor retinaculum bowing ratio, signal intensity ratio of the median, nerve and hypothenar muscle signal intensity. RESULTS: With a cutoff point of 10.9 mm2 of the p-CSA, MRI had a sensitivity and specificity of 97.4% and 80% for diagnosis of CTS, respectively. There was a significant association between the clinical and electrophysiological stage with MRI findings (P < 0.001). There was a positive correlation between the BCTQ score and MRI parameters (0.5 < r < 0.7, P < 0.01). CONCLUSION: MRI has good diagnostic value in evaluating CTS. We recommend using p-CSA ≥10.9 mm2 and ΔCSA ≥2.3 mm2 as MRI diagnostic criteria of CTS.


Assuntos
Síndrome do Túnel Carpal , Humanos , Síndrome do Túnel Carpal/diagnóstico por imagem , Estudos Transversais , Nervo Mediano/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Punho , Ultrassonografia
3.
Radiol Case Rep ; 18(3): 794-798, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36582757

RESUMO

Various types of dermal fillers have been developing for soft tissue augmentation. Even though many fillers have been approved and strictly regulated by authorities, homemade products for body contouring procedures are widely available and easily purchased on websites without prescriptions. It is challenging for radiologists to interpret radiological findings of complicated breast augmentation of unknown origin. While ultrasound is the modality of choice for initial work-up, magnetic resonance imaging (MRI) plays a role as the gold standard in evaluating the integrity of prosthetic implants. Using silicone or water-only MRI sequences may also be able to distinguish them. We report a rare case of breast abscess of a young female patient after self-injection of the mixture of ultrasound gel and shoe glue. The clinical and imaging aspect, especially MRI imaging, will be discussed.

4.
Quant Imaging Med Surg ; 12(6): 3379-3390, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35655836

RESUMO

Background: To explore the value of diffusion tensor imaging (DTI)-derived metrics in quantitative evaluation of carpal tunnel syndrome (CTS). Methods: This prospective cross-sectional study included 39 wrists from 24 symptomatic CTS patients, who underwent clinical, electrophysiological, and magnetic resonance imaging (MRI) evaluations. In addition, 10 wrists of 6 healthy participants were included as controls. Clinical and nerve conduction study (NCS) findings were evaluated and graded according to the Boston Carpal Tunnel Questionnaire (BCTQ) and the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM), respectively. We performed MRI using a 1.5 Tesla scanner. Mean diffusivity (MD), fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) of the median nerve at the distal radioulnar joint (DRUJ) (d), the inlet of the carpal tunnel (CT) at the pisiform level (i), the middle of the CT (m) and the outlet of the CT at the level of the hook of hamate (o), cross-sectional area at the inlet of the CT (iCSA), and the difference between MD and FA of the DRUJ and the outlet of CT (Delta MD and Delta FA) were measured. Results: The CTS patients had significantly lower FA [for example, oFA: mean difference 0.09, 95% confidence interval (CI): 0.05 to 0.12] and significantly higher MD than healthy participants (for example, iMD: mean difference 0.3, 95% CI: 0.03 to 0.57). There was a negative correlation between iCSA with iFA and between mFA and oFA (-0.5

5.
ACS Chem Biol ; 17(5): 1226-1238, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35446557

RESUMO

Natural drimane-type sesquiterpenes, including drimenol, display diverse biological activities. These active compounds are distributed in plants and fungi; however, their accumulation in bacteria remains unknown. Consequently, bacterial drimane-type sesquiterpene synthases remain to be characterized. Here, we report five drimenol synthases (DMSs) of marine bacterial origin, all belonging to the haloacid dehalogenase (HAD)-like hydrolase superfamily with the conserved DDxxE motif typical of class I terpene synthases and the DxDTT motif found in class II diterpene synthases. They catalyze two continuous reactions: the cyclization of farnesyl pyrophosphate (FPP) into drimenyl pyrophosphate and dephosphorylation of drimenyl pyrophosphate into drimenol. Protein structure modeling of the characterized Aquimarina spongiae DMS (AsDMS) suggests that the FPP substrate is located within the interdomain created by the DDxxE motif of N-domain and DxDTT motif of C-domain. Biochemical analysis revealed two aspartate residues of the DDxxE motif that might contribute to the capture of the pyrophosphate moiety of FPP inside the catalytic site of AsDMS, which is essential for efficient cyclization and subsequent dephosphorylation reactions. The middle aspartate residue of the DxDTT motif is also critical for cyclization. Thus, AsDMS utilizes both motifs in the reactions. Remarkably, the unique protein architecture of AsDMS, which is characterized by the fusion of a HAD-like domain (N-domain) and a terpene synthase ß domain (C-domain), significantly differentiates this new enzyme. Our findings of the first examples of bacterial DMSs suggest the biosynthesis of drimane sesquiterpenes in bacteria and shed light on the divergence of the structures and functions of terpene synthases.


Assuntos
Alquil e Aril Transferases , Sesquiterpenos , Ácido Aspártico , Difosfatos , Genes Bacterianos , Sesquiterpenos Policíclicos , Sesquiterpenos/química
6.
Nat Prod Res ; 36(7): 1774-1780, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32901507

RESUMO

Phytochemical investigation of the leaves of Lepisanthes rubiginosa led to the isolation of two new glycosides, lepisantheside A (1) and lepisantheside B (2), together with two known compounds acutoside A (3) and 3-O-[ß-D-xylopyranosyl-(1→3)-ß-D-glucopyranosyl-]-oleanolic acid (4). Their structures were elucidated by means of spectroscopic methods (HR-ESI-MS, 1D and 2D NMR), and by comparison with the reported data. The cytotoxicity of compounds 1-4 against four human cancer cell lines (KB, HepG2, SK-LU-1 and MCF7) was evaluated. Compound 4 exhibited significant activity with IC50 values of 9.57, 6.66, 6.97 and 18.32 µM, respectively, in comparison with the postive control ellipticine.


Assuntos
Ácido Oleanólico , Triterpenos , Glicosídeos/química , Humanos , Estrutura Molecular , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/química , Folhas de Planta/química , Triterpenos/química , Vietnã
7.
J Int Med Res ; 49(12): 3000605211064408, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34939464

RESUMO

OBJECTIVE: To examine the value of ultrasound (US) in the diagnosis of carpal tunnel syndrome (CTS) in the Vietnamese population. METHODS: This prospective cross-sectional study involved 42 wrists of 25 patients with idiopathic CTS evaluated by US. In addition, 38 wrists of 22 healthy volunteers were included as the control group. RESULTS: Significant differences in the median nerve cross-sectional area (CSA) at different levels were found between patients with CTS and controls. Using a cut-off value of 9.5 mm2 for the median nerve CSA at the pisiform (p-CSA), US had a sensitivity and specificity of 95.2% and 97.4%, respectively, for the diagnosis of CTS. Area under the curve analysis revealed a sensitivity and specificity of 100% and 95.4%, respectively, for the prediction of severe CTS using a p-CSA of >15.5 mm2. CONCLUSIONS: The median nerve CSA is a highly accurate parameter in the diagnosis of CTS. We recommend using a p-CSA of >9.5 mm2 as a diagnostic criterion for CTS and a p-CSA of >15.5 mm2 as a marker for severe CTS in the Vietnamese population.Research Registry number: 7261.


Assuntos
Síndrome do Túnel Carpal , Povo Asiático , Síndrome do Túnel Carpal/diagnóstico por imagem , Estudos Transversais , Humanos , Nervo Mediano/diagnóstico por imagem , Estudos Prospectivos , Sensibilidade e Especificidade , Ultrassonografia
8.
Radiol Case Rep ; 16(9): 2792-2798, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34367397

RESUMO

We report three cases with Herlyn-Werner-Wunderlich syndrome in adolescents and young female. The objective of this report was to describe the clinical presentation, ultrasound (US) and magnetic resonance imaging (MRI) findings of Herlyn-Werner-Wunderlich syndrome. The three patients were 12, 13 and 34 years old, respectively. The reason for admission and clinical symptoms varied between the 3 patients, including menstrual cramps, vaginal bleeding, and dull pain in the hypogastric region. Nevertheless, the sonographic and MRI findings of all three cases were typical for HWWS, including didelphys uterus, obstructed hemivagina, and ipsilateral renal agenesis.

9.
Radiol Case Rep ; 16(9): 2388-2392, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34257767

RESUMO

We report a case of a 40-year-old female patient admitted to the hospital due to lumbar pain that spread to both legs and was associated with weakness of the lower extremities. Magnetic resonance imaging revealed an intradural - extramedullary tumor at the level of the T12 - L2 vertebra. The lesion was over 7 cm in greatest diameter and compressed the conus medullaris. The patient underwent surgery to remove the entire tumor. Postoperative pathology confirmed the diagnosis of schwannoma. The symptoms resolved almost completely without significant complications.

10.
Clin Case Rep ; 9(3): 1795-1796, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33768943

RESUMO

Rasmussen's encephalitis (RE) is an uncommon cause of the seizure. Important key findings of RE include intractable seizure activity in children, progressive atrophy of the involved hemisphere, and small hemisphere with the large ventricle.

11.
Respirol Case Rep ; 8(8): e00671, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33072329

RESUMO

The focal hepatic hot spot sign appears as an area of intense focal wedge-shaped enhancement of the quadrate lobe (segment IVa) of the liver in the arterial and venous phase. If this sign appears on enhanced computed tomography of the abdomen, obstruction of thoracic central venous must be considered, especially when clinical symptoms are unclear.

12.
Radiol Case Rep ; 15(10): 1799-1802, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32793321

RESUMO

Bowel perforation is an emergency condition. Common causes of bowel perforation include infection, infarction, radiation enteritis, Crohn's disease, and cancer. Ingested foreign body causing bowel perforation is rare. Wooden toothpick-related injuries are uncommon. We report a case of ileal perforation caused by ingested wooden toothpick preoperatively diagnosed by ultrasound and computed tomography.

13.
J Nat Prod ; 82(12): 3311-3320, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31774676

RESUMO

Pentacyclic triterpenes may be active agents and provide a rich natural resource of promising compounds for drug development. The inhibitory activities of 29 natural oleanane and ursane pentacyclic triterpenes were evaluated against four major enzymes involved in the inflammatory process: 5-LOX, 15-LOX-2, COX-1, and COX-2. It was found that 3-O-acetyl-ß-boswellic acid potently inhibited human 15-LOX-2 (IC50 = 12.2 ± 0.47 µM). Analysis of the structure-activity relationships revealed that the presence of a hydroxy group at position 24 was beneficial in terms of both 5-LOX and COX-1 inhibition. Notably, the introduction of a carboxylic acid group at position 30 was important for dual 5-LOX/COX inhibitory activity; furthermore, its combination with a carbonyl group at C-11 considerably increased 5-LOX inhibition. Also, the presence of an α-hydroxy group at C-2 or a carboxylic acid group at C-23 markedly suppressed the 5-LOX activity. The present findings reveal that the types and configurations of polar moieties at positions C-2, -3, -11, -24, and -30 are important structural aspects of pentacyclic triterpenes for their potential as anti-inflammatory lead compounds.


Assuntos
Inibidores de Ciclo-Oxigenase/farmacologia , Inibidores de Lipoxigenase/farmacologia , Triterpenos Pentacíclicos/farmacologia , Inibidores de Ciclo-Oxigenase/química , Avaliação Pré-Clínica de Medicamentos , Humanos , Inibidores de Lipoxigenase/química , Triterpenos Pentacíclicos/química , Relação Estrutura-Atividade
14.
Curr Protoc Toxicol ; 78(1): e59, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30286284

RESUMO

We have developed and validated a method for the simultaneous quantitative measurement of total uranium (TU) and uranium 235 U/238 U isotopic ratio (UIR) in urine by inductively coupled plasma mass spectrometry (ICP-MS) using a Thermo Scientific iCAP-Q instrument. The performance characteristics of the assay were determined to be in compliance with clinical laboratory standards. The assay was linear in the concentration range of 1.0 to 500.0 ng/liter TU. The method was precise and accurate with limits of detection of 2.5 ng/liter for TU and 9.8 ng/liter for UIR. The accuracy was >93% and the coefficient of variation (% CV) was <5.0% for both TU and UIR. All results were within established guidelines and agreed-upon criteria, and the results fell within the certified range for the reference controls. The method has thus been shown to be effective as a simple, precise, and sensitive analytical technique for testing urine samples. © 2018 by John Wiley & Sons, Inc.


Assuntos
Exposição Ambiental/análise , Manejo de Espécimes/métodos , Urânio/urina , Humanos , Limite de Detecção , Radioisótopos/urina , Reprodutibilidade dos Testes , Espectrofotometria Atômica
15.
Curr Protoc Toxicol ; 78(1): e58, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30238639

RESUMO

We developed and validated a method for the assessment of thirteen separate trace and toxic elements using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Included elements were as follows: aluminum, chromium, manganese, iron, cobalt, nickel, copper, zinc, arsenic, molybdenum, cadmium, tungsten, and lead. The measurements of all elements in urine samples were conducted using ICAP-Q ICP-MS in a single method. The performance characteristics of the assay were determined according to clinical laboratory standards. The assay was linear in the concentration range of 1.0 to 1000.0 µg/liter for all elements. The method was precise and accurate with limits of quantitation of 1 µg/liter for chromium, manganese, cobalt, nickel, copper, cadmium, tungsten, and lead; 2 µg/liter for iron and arsenic; 5 µg/liter for aluminum; and 50 µg/liter for zinc. This method has successfully been used for the assessment of all thirteen elements included in urine and has been shown to be effective as a simple, precise, and sensitive analytical technique for biological monitoring of urine samples. © 2018 by John Wiley & Sons, Inc.


Assuntos
Exposição Ambiental/análise , Metais Pesados/urina , Oligoelementos/urina , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Humanos , Limite de Detecção , Metais Pesados/toxicidade , Reprodutibilidade dos Testes , Manejo de Espécimes , Espectrofotometria Atômica , Oligoelementos/toxicidade
16.
J Nat Med ; 71(1): 50-58, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27491744

RESUMO

We evaluated the hemolytic activity of 41 commercially available triterpenoid saponins and sapogenins derived from three types of structural skeletons. Structure-activity relationships were established by comparing the structural characteristics of both the aglycone and sugar moieties among the tested compounds. The majority of oleanane-type sapogenins had stronger hemolytic effects than those of the ursane and dammarane types. The presence of polar regions on sapogenins, such as a carboxyl (COOH) at position 28, an α-hydroxyl (α-OH) at position 16, and/or a ß-hydroxyl (ß-OH) at position 2, significantly enhanced hemolysis. Meanwhile, the introduction of an α-OH at position 2 or a methyl hydroxyl (CH2OH) at positions 23 or 24 was closely associated with reduced activity. Our findings suggest that not only the complexity of sugar moieties but also the types and stereochemical configurations of functional groups at different positions, as well as the skeleton types, are important structural features affecting hemolytic potential. Our results provide a baseline in terms of the toxicity of saponins and sapogenins to erythrocytes, which holds promise for drug development.


Assuntos
Sapogeninas/farmacologia , Saponinas/farmacologia , Triterpenos/farmacologia , Hemólise , Relação Estrutura-Atividade
17.
Clin Infect Dis ; 37(11): 1461-6, 2003 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-14614668

RESUMO

The effectiveness of chloroquine or sulfadoxine-pyrimethamine administered with artesunate for treating uncomplicated falciparum malaria was assessed in 2 Vietnamese provinces where the sensitivity of parasites in vitro to conventional therapies had increased with the removal of drug pressure. In the province of Dac Lac, where potential malaria exposure begins at birth, 57 subjects (mean age, 9.6 years) were randomized to receive artesunate-chloroquine (group 1) or artesunate-sulfadoxine-pyrimethamine (group 2). In the province of Binh Phuoc, 66 nonimmune workers and their relatives (mean age, 24.2 years) were similarly randomized. By day 28 of follow-up, >96% of Dac Lac patients and <52% of Binh Phuoc patients in group 1 and group 2 had an in vivo response that demonstrated sensitivity to therapy. PCR-confirmed cure rates paralleled in vivo results among patients in Binh Phuoc, but PCR results identified 9 (15.7%) of the Dac Lac patients as having experienced asymptomatic, submicroscopic recrudescences. In Dac Lac, pfcrt K76T was near fixation, but infection with parasites with this mutation predicted recrudescence among group 1 patients in Binh Phuoc. Common pfdhfr mutations did not predict outcome in group 2. The successful reintroduction of conventional therapies in combination with artesunate depends on epidemiological and/or parasitological factors.


Assuntos
Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Cloroquina/uso terapêutico , Malária Falciparum/tratamento farmacológico , Pirimetamina/uso terapêutico , Sesquiterpenos/uso terapêutico , Sulfadoxina/uso terapêutico , Adolescente , Adulto , Animais , Artesunato , Criança , Combinação de Medicamentos , Quimioterapia Combinada , Feminino , Genótipo , Humanos , Masculino , Resultado do Tratamento , Vietnã
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