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1.
Eur Radiol ; 34(2): 1222-1231, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37615762

RESUMO

OBJECTIVES: To evaluate a CT-based radiomics model for identifying malignant pancreatic intraductal papillary mucinous neoplasms (IPMNs) and compare its performance with the 2017 international consensus guidelines (ICGs). MATERIALS AND METHODS: We retrospectively included 194 consecutive patients who underwent surgical resection of pancreatic IPMNs between January 2008 and December 2020. Surgical histopathology was the reference standard for diagnosing malignancy. Using radiomics features from preoperative contrast-enhanced CT, a radiomics model was built with the least absolute shrinkage and selection operator by a five-fold cross-validation. CT and MR images were independently reviewed based on the 2017 ICGs by two abdominal radiologists, and the performances of the 2017 ICGs and radiomics model were compared. The areas under the curve (AUCs) were compared using the DeLong method. RESULTS: A total of 194 patients with pancreatic IPMNs (benign, 83 [43%]; malignant, 111 [57%]) were chronologically divided into training (n = 141; age, 65 ± 8.6 years; 88 males) and validation sets (n = 53; age, 66 ± 9.7 years; 31 males). There was no statistically significant difference in the diagnostic performance of the 2017 ICGs between CT and MRI (AUC, 0.71 vs. 0.71; p = 0.93) with excellent intermodality agreement (k = 0.86). In the validation set, the CT radiomics model had higher AUC (0.85 vs. 0.71; p = 0.038), specificity (84.6% vs. 61.5%; p = 0.041), and positive predictive value (84.0% vs. 66.7%; p = 0.044) than the 2017 ICGs. CONCLUSION: The CT radiomics model exhibited better diagnostic performance than the 2017 ICGs in classifying malignant IPMNs. CLINICAL RELEVANCE STATEMENT: Compared with the radiologists' evaluation based on the 2017 international consensus guidelines, the CT radiomics model exhibited better diagnostic performance in classifying malignant intraductal papillary mucinous neoplasms. KEY POINTS: • There is a paucity of comparisons between the 2017 international consensus guidelines (ICGs) and radiomics models for malignant intraductal papillary mucinous neoplasms (IPMNs). • The CT radiomics model developed in this study exhibited better diagnostic performance than the 2017 ICGs in classifying malignant IPMNs. • The radiomics model may serve as a valuable complementary tool to the 2017 ICGs, potentially allowing a more quantitative assessment of IPMNs.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Císticas, Mucinosas e Serosas , Neoplasias Intraductais Pancreáticas , Neoplasias Pancreáticas , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Radiômica , Estudos Retrospectivos , Carcinoma Ductal Pancreático/diagnóstico , Neoplasias Pancreáticas/diagnóstico
2.
Appl Microbiol Biotechnol ; 108(1): 86, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38189951

RESUMO

Despite the discovery of several bacteria capable of interacting with polymers, the activity of the natural bacterial isolates is limited. Furthermore, there is a lack of knowledge regarding the development of bioprocesses for polyethylene (PE) degradation. Here, we report a bioprocess using pseudo-resting cells for efficient degradation of PE. The bacterial strain Acinetobacter nosocomialis was isolated from PE-containing landfills and characterized using low-density PE (LDPE) surface oxidation when incubated with LDPE. We optimized culture conditions to generate catalytic pseudo-resting cells of A. nosocomialis that are capable of degrading LDPE films in a bioreactor. After 28 days of bioreactor operation using pseudo-resting cells of A. nosocomialis, we observed the formation of holes on the PE film (39 holes per 217 cm2, a maximum diameter of 1440 µm). This study highlights the potential of bacteria as biocatalysts for the development of PE degradation processes. KEY POINTS: • New bioprocess has been proposed to degrade polyethylene (PE). • Process with pseudo-resting cells results in the formation of holes in PE film. • We demonstrated PE degradation using A. nosocomialis as a biocatalyst.


Assuntos
Acinetobacter , Polietileno , Reatores Biológicos , Catálise
3.
AJR Am J Roentgenol ; 221(1): 80-90, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36856300

RESUMO

BACKGROUND. When coronary CTA is performed in the emergency department (ED), the use of a contemporary scanner with improved temporal resolution may eliminate the need to administer ß-blockers for heart rate (HR) control, thereby expediting workup. OBJECTIVE. The purpose of this study was to compare ED length of stay (LOS), image quality, frequency of nondiagnostic examinations, and other clinical outcomes between patients undergoing coronary CTA in the ED on a single-source CT (SSCT) scanner with HR control versus on a dual-source CT (DSCT) scanner without HR control. METHODS. This retrospective study included 509 patients (283 men, 226 women; mean age, 52.1 ± 15.1 [SD] years) at low to intermediate risk for acute coronary syndrome who underwent coronary CTA for acute chest pain during off-hours in a single ED from March 1, 2020, to April 25, 2022. A total of 205 patients initially underwent CTA using a 64-detector-row SSCT scanner with HR control (oral ß-blocker administration if HR was > 65 beats/min); after scanner replacement on April 26, 2021, 304 patients underwent CTA using a third-generation DSCT without HR control. Groups were compared in terms of ED LOS and CT completion time (defined as time from ordering CTA to completion of acquisition) using propensity score matching and additional endpoints including image quality and nondiagnostic examinations based on radiology reports. RESULTS. The DSCT group, compared with the SSCT group, showed no significant difference in median ED LOS (505 vs 457 minutes, respectively; p = .37) but showed shorter median CT completion time (95 vs 117 minutes, p < .001); on the basis of a mediation analysis, 89% of the reduction in CT completion time for DSCT was attributed to the absence of HR control. The DSCT group, compared with the SSCT group, showed higher frequency of examinations with good or excellent image quality (87.8% vs 60.0%, p < .001) and lower frequency of nondiagnostic examinations (1.6% vs 6.3%, p = .01) but showed no significant difference in frequencies of emergent cardiology consultation, invasive angiography, ED disposition, or coronary revascularization (all p > .05). No patient in either group experienced 30-day all-cause mortality or a major adverse cardiovascular event. CONCLUSION. The use of a DSCT scanner for coronary CTA can eliminate the need for ß-blocker administration for HR control while decreasing nondiagnostic examinations. CLINICAL IMPACT. A DSCT scanner can expedite clinical processes in the ED.


Assuntos
Dor no Peito , Coração , Masculino , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Angiografia Coronária/métodos , Estudos Retrospectivos , Dor no Peito/diagnóstico por imagem , Serviço Hospitalar de Emergência , Doses de Radiação
4.
Anal Bioanal Chem ; 415(19): 4805-4812, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37269307

RESUMO

A certified reference material (CRM), KRISS CRM 108-02-006, was developed for the accurate analysis of low levels of acrylamide in infant formula matrices. The CRM is an infant formula fortified with acrylamide at a similar level as that stipulated by the European Union regulation for baby food. Commercially available infant formulas were processed by freeze-drying, and the subsequent homogenization of the fortified material to produce 961 bottles of the CRM in one batch. The CRM bottles containing approximately 15 g of the material in each unit were stored in a storage room at - 70 ℃. High-purity acrylamide was used as the primary reference material, and its purity was assessed using an in-house mass-balance method to obtain results metrologically traceable to the International System of Units. The acrylamide content of the infant formula CRM was evaluated using isotope dilution-liquid chromatography/mass spectrometry as a reference method, which was established by our research group. An acrylamide content of 55.7 ± 2.1 µg/kg was assigned as the certified value of the CRM with the expanded uncertainty at a 95% confidence level. The homogeneity study showed good uniformity of the acrylamide content among units, providing a relative standard deviation of 1.2% of the mean value. A stability study was also performed by monitoring the CRM under different temperature conditions and periods. The stability results indicated that the acrylamide content in the CRM under the storage conditions of - 70 ℃ remained stable for up to 10 months.


Assuntos
Acrilamida , Fórmulas Infantis , Lactente , Humanos , Padrões de Referência , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos
5.
Molecules ; 28(22)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38005289

RESUMO

Analytical methods based on the mass balance approach were developed for the purity evaluation of tetracycline hydrochloride, a representative salt compound used in pure veterinary drug analysis. The purity assignment method was used to quantify individual classes of impurities via independent analytical techniques. The mass fraction of the free base or salt form contained in a high-purity organic compound with a hydrochloride salt can be determined. The chloride content by ion chromatography-conductivity detector (IC-CD) and general classes of impurities, including structurally related impurities by liquid chromatography-ultraviolet (LC-UV) detector, water by Karl Fischer (KF) coulometric titration, residual solvents by headspace sampler gas chromatography/mass spectrometry (HS-GC/MS), and non-volatiles by thermogravimetric analyzer (TGA), were considered to calculate the purity of the mass fraction. The chloride content of the salt compound can be considered the main impurity in the mass fraction of the free base in the salt compound. A purity assay using quantitative nuclear magnetic resonance (q-NMR) as a direct determination method was performed to confirm the results of the mass balance method. The assigned purities of the tetracycline free form and its salt form in mass fraction were (898.80 ± 1.60) mg/g and (972.65 ± 1.58) mg/g, respectively, which are traceable to the international system of units (SI). Thus, the procedure for evaluating the purity of the free base and salt forms in the salt compound is newly demonstrated in this study.


Assuntos
Cloretos , Tetraciclina , Cromatografia Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas
6.
Radiology ; 303(2): 351-358, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35133200

RESUMO

Background Preoperative assessment of pathologic complete response (pCR) in locally advanced rectal cancer (LARC) after neoadjuvant chemoradiotherapy (nCRT) is increasingly needed for organ preservation, but large-scale validation of an MRI radiomics model remains lacking. Purpose To evaluate radiomics models based on T2-weighted imaging and diffusion-weighted MRI for predicting pCR after nCRT in LARC and compare their performance with visual assessment by radiologists. Materials and Methods This retrospective study included patients with LARC (clinical stage T3 or higher, positive nodal status, or both) who underwent post-nCRT MRI and elective resection between January 2009 and December 2018. Surgical histopathologic analysis was the reference standard for pCR. Radiomic features were extracted from the volume of interest on T2-weighted images and apparent diffusion coefficient (ADC) maps from post-nCRT MRI to generate three models: T2 weighted, ADC, and both T2 weighted and ADC (merged). Radiomics signatures were generated using the least absolute shrinkage and selection operator with tenfold cross-validation. Three experienced radiologists independently rated tumor regression grades at MRI and compared these with the radiomics models' diagnostic outcomes. Areas under the curve (AUCs) of the radiomics models and pooled readers were compared by using the DeLong method. Results Among 898 patients, 189 (21%) achieved pCR. The patients were chronologically divided into training (n = 592; mean age ± standard deviation, 59 years ± 12; 388 men) and test (n = 306; mean age, 59 years ± 12; 190 men) sets. The radiomics signatures of the T2-weighted, ADC, and merged models demonstrated AUCs of 0.82, 0.79, and 0.82, respectively, with no evidence of a difference found between the T2-weighted and merged models (P = .49), while the ADC model performed worse than the merged model (P = .02). The T2-weighted model had higher classification performance (AUC, 0.82 vs 0.74 [P = .009]) and sensitivity (80.0% vs 15.6% [P < .001]), but lower specificity (68.4% vs 98.6% [P < .001]) than the pooled performance of the three radiologists. Conclusion An MRI-based radiomics model showed better classification performance than experienced radiologists for diagnosing pathologic complete response in patients with locally advanced rectal cancer after neoadjuvant chemoradiotherapy. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Taylor in this issue.


Assuntos
Neoplasias Retais , Quimiorradioterapia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/terapia , Estudos Retrospectivos
7.
Reprod Fertil Dev ; 34(16): 1052-1057, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36109872

RESUMO

CONTEXT: Despite the absence of light within the body, the application of microscopy during stages of in vitro embryo production has led to the discovery of light irradiation effects on embryo preimplantation development. AIMS: To determine the optimal light irradiation wavelengths at various embryo stages for improving the preimplantation development of mouse embryos and the quality (total cell number) of blastocysts. METHOD: All in vitro procedures of zygote or 2-cell embryo manipulation, embryo monitoring, and culture medium exchange were conducted under visible (390-750nm), blue (445-500nm), green (500-575nm), yellow (575-585nm), or red (620-750nm) light irradiation wavelength. KEY RESULTS: We found that blue, green, and yellow light irradiation during in vitro blastocyst production from zygotes significantly improved blastocyst production and quality, compared to visible and red light irradiation. However, 2-cell embryos exposed to yellow light during in vitro blastocyst production produced significantly more high-quality blastocysts than did 2-cell embryos exposed to visible, blue, green, or red light. After exposure to blue and green - but not yellow - light during in vitro zygote manipulation, yellow light irradiation during embryo monitoring and culture medium exchange triggered significant retardation of preimplantation development. CONCLUSION: These results demonstrate that yellow light irradiation during in vitro blastocyst production, regardless of embryo stage, improves preimplantation development of mouse embryos. IMPLICATIONS: The present study will contribute to produce greater high-quality blastocysts and reduce experimental errors generated by light exposure during mouse embryo-related studies.


Assuntos
Blastocisto , Embrião de Mamíferos , Desenvolvimento Embrionário , Luz , Animais , Blastocisto/efeitos da radiação , Meios de Cultura , Embrião de Mamíferos/efeitos da radiação , Desenvolvimento Embrionário/efeitos da radiação , Luz/efeitos adversos , Camundongos , Zigoto
8.
J Hepatol ; 74(1): 109-121, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32818570

RESUMO

BACKGROUND & AIMS: Despite the clinical and genetic significance of macrotrabecular-massive hepatocellular carcinoma (MTM-HCC), its characteristics on imaging have not been described. This study aimed to characterise MTM-HCC on gadoxetic acid-enhanced MRI and to evaluate the diagnostic accuracy and prognostic value of these imaging characteristics. METHODS: We enrolled 3 independent cohorts from 2 tertiary care centres. The 3 cohorts consisted of a total of 476 patients who underwent gadoxetic acid-enhanced MRI and surgical resection for treatment-naïve single HCCs. Independent review of histopathology and MRI by 2 reviewers was performed for each cohort, and inter-reader agreement was evaluated. Based on the result of MRI review in the training cohort (cohort 1), we developed 2 diagnostic criteria for MTM-HCC and evaluated their prognostic significance. The diagnostic performance and prognostic significance were validated in 2 validation cohorts (cohorts 2 and 3). RESULTS: We developed 2 diagnostic MRI criteria (MRIC) for MTM-HCC: MRIC-1, ≥20% arterial phase hypovascular component; MRIC-2, ≥50% hypovascular component and 2 or more ancillary findings (intratumoural artery, arterial phase peritumoural enhancement, and non-smooth tumour margin). MRIC-1 showed high sensitivity and negative predictive value (88% and 95% in the training cohort, and 88% and 97% in the pooled validation cohorts, respectively), whereas MRIC-2 demonstrated moderate sensitivity and high specificity (47% and 94% in the training cohort, and 46% and 96% in the pooled validation cohorts, respectively). MRIC-2 was an independent poor prognostic factor for overall survival in both training and pooled validation cohorts. CONCLUSIONS: Using gadoxetic acid-enhanced MRI findings, including an arterial phase hypovascular component, we could stratify the probability of MTM-HCC and non-invasively obtain prognostic information. LAY SUMMARY: Macrotrabecular-massive hepatocellular carcinoma (MTM-HCC) is a histopathologic subtype of HCC characterised by aggressive biological behaviour and poor prognosis. We developed imaging criteria based on liver MRI that could be used for the non-invasive diagnosis of MTM-HCC. HCCs showing imaging findings of MTM-HCC were associated with poor outcomes after hepatic resection.


Assuntos
Carcinoma Hepatocelular , Gadolínio DTPA/farmacologia , Hepatectomia/métodos , Neoplasias Hepáticas , Fígado , Imageamento por Ressonância Magnética/métodos , Biópsia/métodos , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Meios de Contraste/farmacologia , Feminino , Humanos , Aumento da Imagem/métodos , Fígado/diagnóstico por imagem , Fígado/patologia , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , República da Coreia/epidemiologia , Sensibilidade e Especificidade , Análise de Sobrevida , Carga Tumoral
9.
Stem Cells ; 38(7): 904-916, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32277785

RESUMO

Human mesenchymal stem cells (MSCs) are promising therapeutics for autoimmune diseases due to their immunomodulatory effects. In particular, human umbilical cord blood-derived MSCs (hUCB-MSCs) have a prominent therapeutic effect on atopic dermatitis (AD). However, the underlying mechanism is unclear. This study investigated the role of transforming growth factor-beta (TGF-ß) in the therapeutic effect of hUCB-MSCs on AD. Small interfering RNA (siRNA)-mediated depletion of TGF-ß disrupted the therapeutic effect of hUCB-MSCs in a mouse model of AD by attenuating the beneficial changes in histopathology, mast cell infiltration, tumor necrosis factor-alpha (TNF-α) expression, and the serum IgE level. To confirm that hUCB-MSCs regulate secretion of TNF-α, we investigated whether they inhibit TNF-α secretion by activated LAD2 cells. Coculture with hUCB-MSCs significantly inhibited secretion of TNF-α by LAD2 cells. However, this effect was abolished by siRNA-mediated depletion of TGF-ß in hUCB-MSCs. TNF-α expression in activated LAD2 cells was regulated by the extracellular signal-related kinase signaling pathway and was suppressed by TGF-ß secreted from hUCB-MSCs. In addition, TGF-ß secreted by hUCB-MSCs inhibited maturation of B cells. Taken together, our findings suggest that TGF-ß plays a key role in the therapeutic effect of hUCB-MSCs on AD by regulating TNF-α in mast cells and maturation of B cells.


Assuntos
Dermatite Atópica , Imunoglobulina E , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Animais , Dermatite Atópica/terapia , Sangue Fetal , Humanos , Imunoglobulina E/metabolismo , Imunoglobulina E/farmacologia , Mastócitos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Cordão Umbilical
10.
BMC Med Inform Decis Mak ; 21(1): 311, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34749731

RESUMO

BACKGROUND: Interpretation of chest radiographs (CRs) by emergency department (ED) physicians is inferior to that by radiologists. Recent studies have investigated the effect of deep learning-based assistive technology on CR interpretation (DLCR), although its relevance to ED physicians remains unclear. This study aimed to investigate whether DLCR supports CR interpretation and the clinical decision-making of ED physicians. METHODS: We conducted a prospective interventional study using a web-based performance assessment system. Study participants were recruited through the official notice targeting board for certified emergency physicians and residents working at the present ED. Of the eight ED physicians who volunteered to participate in the study, seven ED physicians were included, while one participant declared withdrawal during performance assessment. Seven physicians' CR interpretations and clinical decision-making were assessed based on the clinical data from 388 patients, including detecting the target lesion with DLCR. Participant performance was evaluated by area under the receiver operating characteristic curve (AUROC), sensitivity, specificity, and accuracy analyses; decision-making consistency was measured by kappa statistics. ED physicians with < 24 months of experience were defined as 'inexperienced'. RESULTS: Among the 388 simulated cases, 259 (66.8%) had CR abnormality. Their median value of abnormality score measured by DLCR was 59.3 (31.77, 76.25) compared to a score of 3.35 (1.57, 8.89) for cases of normal CR. There was a difference in performance between ED physicians working with and without DLCR (AUROC: 0.801, P < 0.001). The diagnostic sensitivity and accuracy of CR were higher for all ED physicians working with DLCR than for those working without it. The overall kappa value for decision-making consistency was 0.902 (95% confidence interval [CI] 0.884-0.920); concurrently, the kappa value for the experienced group was 0.956 (95% CI 0.934-0.979), and that for the inexperienced group was 0.862 (95% CI 0.835-0.889). CONCLUSIONS: This study presents preliminary evidence that ED physicians using DLCR in a clinical setting perform better at CR interpretation than their counterparts who do not use this technology. DLCR use influenced the clinical decision-making of inexperienced physicians more strongly than that of experienced physicians. These findings require prospective validation before DLCR can be recommended for use in routine clinical practice.


Assuntos
Aprendizado Profundo , Médicos , Tecnologia Assistiva , Serviço Hospitalar de Emergência , Humanos , Radiografia Torácica
11.
Biochem Biophys Res Commun ; 522(1): 213-219, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31759627

RESUMO

In cell-based tissue engineering, fibrin hydrogel can be utilized to produce scaffolds to treat cartilage. However, the optimal fibrin formulation for cartilage regeneration has not yet been studied. This study aimed to find the optimal fibrin formulation and determine whether fibrin optimized with human adipose-derived stem cells (hASCs) increased the in-vivo chondrogenic potential. To find the optimal formulation, fibrin constructs were divided into twelve groups with different ratios of fibrinogen (10, 20, 30, and 50 mg/mL) to thrombin (10, 50, and 100 IU/mL), following which the physical and biological properties of cell-free and cell-embedded fibrin were investigated. The results from cell-free hydrogels showed that increases in the concentrations of fibrinogen and thrombin corresponded to increases in stiffness and initial weight. Moreover, hydrogel degradation was inhibited in high-concentration formulations. In cell-embedded fibrin constructs, the variation of gel formulation did not affect cell viability. However, cell behavior depended on the gel formulation. hASCs within high-concentration fibrinogen formulation maintained a round morphology similar to natural chondrocytes. Variations in thrombin concentration had a lesser effect on cell morphology. In terms of in-vivo cartilage formation, the formulation with 30 mg/mL fibrinogen and 100 IU/mL thrombin showed the highest cartilage formation, as evidenced through collagen type II alpha 1 chain (COL2) and safranin-O, 4 weeks after implantation. The results may lead to optimally designed 3D bio-scaffolds in which we can control both cell survival and chondrogenic potential for cartilage tissue engineering. Scaffolds made with the optimal fibrin formulation can be applied to develop cell therapies with mesenchymal stem cells to treat osteoarthritis.


Assuntos
Condrogênese , Fibrina/química , Hidrogéis/química , Células-Tronco Mesenquimais/citologia , Alicerces Teciduais/química , Diferenciação Celular , Linhagem Celular , Humanos , Engenharia Tecidual
12.
BMC Evol Biol ; 18(1): 52, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29642844

RESUMO

BACKGROUND: Life history characteristics are considered important factors influencing the evolutionary processes of natural populations, including the patterns of population genetic structure of a species. The sister species Cottus hangiongensis and C. koreanus are small bottom-dwelling freshwater sculpin fishes from South Korea that display marked life history divergence but are morphologically nearly indistinguishable. Cottus hangiongensis evolved an 'amphidromous' life history with a post-hatching pelagic larval phase. They spawn many small eggs in the low reaches of rivers, and hatched larvae migrate to the sea before returning to grow to maturity in the river mouth. In contrast, C. koreanus evolved a 'fluvial' landlocked type with benthic larvae. They release a smaller number of larger eggs, and the larvae undergo direct development, remaining benthic in the upstream rivers throughout their entire lives. We tested whether there were differences in patterns and levels of within-population genetic diversities and spatial population structure between the two closely related Korean sculpins using mitochondrial DNA control region sequences and seven nuclear microsatellite loci. RESULTS: The combined analyses of both marker sets revealed that C. hangiongensis harboured considerably higher levels of within-population genetic diversities (e.g. haplotype/allelic richness, heterozygosities) than C. koreanus. In contrast, the fluvial sculpin exhibited noticeably more spatial population structure than did the amphidromous sculpin, as suggested by pairwise FST statistics. The finding that C. hangiongensis individuals comprised a single random mating population across the east-flowing river basins in the Korean Peninsula, whereas C. koreanus individuals comprised genetically discrete individual populations, was further supported by an individual-based Bayesian population assignment and also factorial correspondence analyses. CONCLUSIONS: The higher genetic diversity, but lower population structure, of the amphidromous sculpin relative to the fluvial sculpin may have resulted from its greater larval dispersal and also possibly, higher fecundity accompanied by an amphidromous life history. Hence, we conclude that contrasting early life histories - including the presence or absence of the pelagic larval phase - may have led to divergent patterns of within-population genetic diversities and spatial population structure between the sister Cottus species following speciation from a common ancestor of marine sculpin.


Assuntos
Variação Genética , Perciformes/classificação , Perciformes/genética , Animais , Teorema de Bayes , Evolução Biológica , DNA Mitocondrial/genética , Genética Populacional , Larva/genética , Repetições de Microssatélites , Filogenia , República da Coreia , Rios
13.
Ann Surg Oncol ; 25(11): 3222-3230, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30051367

RESUMO

BACKGROUND: There is increasing interest in the influence of body composition on oncological outcomes. We evaluated the role of skeletal muscle and fat among patients with gastric cancer (GC) who underwent gastrectomy with or without adjuvant chemotherapy, as well as those changes' associations with survival outcomes. METHODS: The present study evaluated 136 patients with GC who were enrolled in the CLASSIC Trial at Yonsei Cancer Center. Baseline body compositions including skeletal muscle area, Hounsfield units (HU), visceral fat area, and subcutaneous fat area were measured by preoperative computed tomography (CT). CT before and after the gastrectomy were used to determine the 6-month relative changes in body composition parameters. Continuous variables were dichotomized according to the best cutoff values by Contal and O'Quigley method. RESULTS: Seventy-three patients (53.7%) underwent surgery alone, and 63 patients (46.3%) underwent surgery followed by adjuvant chemotherapy. The baseline body composition parameters were not associated with disease-free survival (DFS) or overall survival (OS). Except for the HU, the marked loss of muscle, visceral fat, or subcutaneous fat significantly predicted shorter DFS and OS. Patients with a marked loss in at least one significant body composition parameter had significantly shorter DFS (hazard ratio 2.9, 95% confidence interval 1.7-4.8, P < 0.001) and OS (hazard ratio 2.9, 95% confidence interval 1.7-5.0, P < 0.001). CONCLUSIONS: Marked loss in body composition parameters significantly predicted shorter DFS and OS among patients with GC who underwent gastrectomy. Postoperative nutrition and active healthcare interventions could improve the prognosis of these GC patients.


Assuntos
Adenocarcinoma/mortalidade , Gastrectomia/efeitos adversos , Gordura Intra-Abdominal/patologia , Complicações Pós-Operatórias , Sarcopenia/mortalidade , Neoplasias Gástricas/mortalidade , Gordura Subcutânea/patologia , Adenocarcinoma/secundário , Adenocarcinoma/cirurgia , Adulto , Idoso , Composição Corporal , Feminino , Seguimentos , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Sarcopenia/etiologia , Sarcopenia/patologia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Taxa de Sobrevida , Adulto Jovem
14.
BMC Cancer ; 18(1): 1116, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30442107

RESUMO

BACKGROUND: With advances in gastric cancer chemotherapy, conversion surgery has drawn attention as a new strategy to improve the outcome of stage IV disease. We investigated the efficacy of conversion surgery following chemotherapy for patients with stage IV gastric cancer. METHODS: We retrospectively reviewed clinico-pathologic variables and oncologic outcomes for 101 patients with stage IV gastric cancer who were treated with systemic chemotherapy followed by gastrectomy with intension of curative resection from January 2005 to December 2012. RESULTS: In terms of the best response from palliative chemotherapy, complete or partial response were observed in 65 patients (64.4%) in overall. Complete response of metastatic site were observed in 72 (71.3%) and 66 (65.3%) patients as best and pre-operative response, respectively. The overall complete macroscopic resection, rate was 56.4%. Eleven patients (10.9%) received combined metastasectomy. There was no postoperative surgery-related mortality for 1 month. The median overall survival time was 26.0 months. Multivariable analysis identified complete macroscopic resection, chemotherapy response (complete response/partial response) of metastatic sites, and change in CEA level as independent prognostic factors contributing to overall survival. CONCLUSIONS: Patients with stage IV gastric cancer who exhibit a good clinical response to chemotherapy might obtain greater survival benefit from gastrectomy following chemotherapy compared with patients who exhibit a poor response to chemotherapy. Prospective, randomized trials are required to determine the best strategy for combining initial chemotherapy with subsequent gastrectomy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Gastrectomia/métodos , Metastasectomia/métodos , Cuidados Paliativos/métodos , Neoplasias Gástricas/terapia , Adulto , Idoso , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Equipe de Assistência ao Paciente , Seleção de Pacientes , Estudos Retrospectivos , Estômago/patologia , Estômago/cirurgia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Resultado do Tratamento
15.
Liver Int ; 38(9): 1655-1663, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29495116

RESUMO

BACKGROUND & AIMS: The European Association for the Study of the Liver criteria and the modified Response Evaluation Criteria in Solid Tumors are used for assessing the treatment outcomes of hepatocellular carcinoma. We investigated the inter- and intra-observer reproducibility of the European Association for the Study of the Liver criteria and modified Response Evaluation Criteria in Solid Tumors in patients with advanced hepatocellular carcinoma treated with sorafenib. METHODS: A total of 99 patients with treatment-naive advanced hepatocellular carcinoma receiving sorafenib were included. The κ-values for the inter- and intra-observer agreement of the treatment response were calculated. RESULTS: Inter-observer agreement for baseline tumour number was excellent, as reflected by the high κ-value. The κ-statistics showed "excellent" concordance between the 2 sets of measurements by observer A regarding the overall responses using the European Association for the Study of the Liver criteria (κ = .948, agreement rate = 84.8%) and modified Response Evaluation Criteria in Solid Tumors (κ = .944, agreement rate = 83.8%; all P < .001). In addition, high κ-values indicated concordance between the first sets of measurements by observers A and B (κ = .991 by the European Association for the Study of the Liver criteria and .988 by modified Response Evaluation Criteria in Solid Tumors, all P < .001). When agreements in radiological overall responses between the 2 sets of measurements by observer B and between the second sets of measurements by observers A and B were calculated, similar results regarding high κ-values (>.8) were obtained. CONCLUSIONS: The reproducibility of the European Association for the Study of the Liver criteria and modified Response Evaluation Criteria in Solid Tumors in assessing treatment outcomes was high in patients with advanced hepatocellular carcinoma treated with sorafenib.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Sorafenibe/uso terapêutico , Idoso , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , República da Coreia , Critérios de Avaliação de Resposta em Tumores Sólidos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
16.
Cell Biol Int ; 42(9): 1221-1227, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29809293

RESUMO

In vitro expansion of undifferentiated porcine primed embryonic stem (ES) cells is facilitated by use of non-cellular niches that mimic three-dimensional (3D) microenvironments enclosing an inner cell mass of porcine blastocysts. Therefore, we investigated the integrin heterodimers on the surface of undifferentiated porcine primed ES cells for the purpose of developing a non-cellular niche to support in vitro maintenance of the self-renewal ability of porcine primed ES cells. Immunocytochemistry and a fluorescence immunoassay were performed to assess integrin α and ß subunit levels, and attachment and antibody inhibition assays were used to evaluate the function of integrin heterodimers. The integrin α3 , α5 , α6 , α9 , αV , and ß1 subunits, but not the α1 , α2 , α4 , α7 , and α8 subunits, were identified on the surface of undifferentiated porcine primed ES cells. Subsequently, significant increase of their adhesion to fibronectin, tenascin C, and vitronectin were observed and functional blocking of integrin heterodimer α5 ß1 , α9 ß1 , or αV ß1 showed significantly inhibited adhesion to fibronectin, tenascin C, or vitronectin. No integrin α6 ß1 heterodimer-mediated adhesion to laminin was detected. These results demonstrate that active α5 ß1 , α9 ß1 , and αV ß1 integrin heterodimers are present on the surface of undifferentiated porcine primed ES cells, together with inactive integrin α3 (presumed) and α6 subunits.


Assuntos
Adesão Celular/fisiologia , Células-Tronco Embrionárias/metabolismo , Integrinas/metabolismo , Animais , Técnicas de Cultura de Células/métodos , Diferenciação Celular/fisiologia , Células Cultivadas , Células-Tronco Embrionárias/fisiologia , Matriz Extracelular/metabolismo , Células Alimentadoras , Fibronectinas/metabolismo , Cadeias alfa de Integrinas/metabolismo , Cadeias alfa de Integrinas/fisiologia , Cadeias beta de Integrinas/metabolismo , Cadeias beta de Integrinas/fisiologia , Integrinas/fisiologia , Laminina/metabolismo , Camundongos , Suínos , Tenascina , Vitronectina
17.
Biochem Biophys Res Commun ; 488(2): 273-277, 2017 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-28472624

RESUMO

Acquisition of sperm capacitation post-ejaculation into the female reproductive tract is an essential step in the fertilization process. Accordingly, during in vitro fertilization, successful fertilization requires the induction of capacitation in epididymis-retrieved sperm. To date, many candidate substances have been considered as capacitation inducers; however, there are no reports on the efficiency of inducing sperm capacitation among the diverse inducers. Therefore, we attempted to determine the inducer with the best capacitation in inbred mouse sperm by comparing the capacitation performance of a variety of inducers and the percentage of in vitro fertilization-generated zygotes. Calcium chloride, progesterone, bovine serum albumin (BSA), heparin, and lysophosphatidylcholine (Lyso-PC) were used as candidate capacitation inducers. Optimized concentrations of each inducer (2.7 mM calcium, 15 µM progesterone, 0.3% (w/v) BSA, 50 mM heparin, and 100 µM Lyso-PC) were determined based on the ratio of sperm showing an acrosome reaction using Coomassie G-250 blue staining. Calcium at 2.7 mM showed the strongest capacitation induction compared to the other inducers. In vitro fertilization was performed using sperm incubated in each inducer and the ratio of fertilized oocytes was determined. Calcium at 2.7 mM and 0.3% (w/v) BSA showed the highest fertilization rates compared to 15 µM progesterone, 50 mM heparin, and 100 µM Lyso-PC. From these results, we found that 2.7 mM calcium and 0.3% (w/v) BSA were the most effective sperm capacitation inducers of mouse sperm for in vitro fertilization.


Assuntos
Epididimo/efeitos dos fármacos , Capacitação Espermática/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Animais , Cloreto de Cálcio/farmacologia , Relação Dose-Resposta a Droga , Heparina/farmacologia , Lisofosfatidilcolinas/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Progesterona/farmacologia , Soroalbumina Bovina/farmacologia , Relação Estrutura-Atividade
18.
Biochem Biophys Res Commun ; 461(2): 348-53, 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-25887802

RESUMO

Although episomal vectors are commonly transported into cells by electroporation, a number of electroporation-derived problems have led to the search for alternative transfection protocols, such as the use of transfection reagents, which are inexpensive and easy to handle. Polyplex-mediated transport of episomal vectors into the cytoplasm has been conducted successfully in immortalized cell lines, but no report exists of successful transfection of primary cells using this method. Accordingly, we sought to optimize the conditions for polyplex-mediated transfection for effective delivery of episomal vectors into the cytoplasm of primary mouse embryonic fibroblasts. Episomal vectors were complexed with the commercially available transfection reagents Lipofectamine 2000, FuGEND HD and jetPEI. The ratio of transfection reagent to episomal vectors was varied, and the subsequent transfection efficiency and cytotoxicity of the complexes were analyzed using flow cytometry and trypan blue exclusion assay, respectively. No cytotoxicity and the highest transfection yield were observed when the ratio of transfection reagent to episomal vector was 4 (v/wt) in the cases of Lipofectamine 2000 and FuGENE HD, and 2 in the case of jetPEI. Of the three transfection reagents tested, jetPEI showed the highest transfection efficiency without any cytotoxicity. Thus, we confirmed that the transfection reagent jetPEI could be used to effectively deliver episomal vectors into primary cells without electroporation.


Assuntos
Vetores Genéticos/administração & dosagem , Plasmídeos/administração & dosagem , Transfecção/métodos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Eletroporação/métodos , Vetores Genéticos/química , Vetores Genéticos/genética , Proteínas de Fluorescência Verde/genética , Lipídeos/química , Lipídeos/toxicidade , Camundongos , Plasmídeos/química , Plasmídeos/genética
19.
Anal Bioanal Chem ; 407(18): 5433-42, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25925860

RESUMO

Patulin, a mycotoxin produced by several molds in fruits, has been frequently detected in apple products. Therefore, regulatory bodies have established recommended maximum permitted patulin concentrations for each type of apple product. Although several analytical methods have been adopted to determine patulin in food, quality control of patulin analysis is not easy, as reliable certified reference materials (CRMs) are not available. In this study, as a part of a project for developing CRMs for patulin analysis, we developed isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC/MS/MS) as a higher-order reference method for the accurate value-assignment of CRMs. (13)C7-patulin was used as internal standard. Samples were extracted with ethyl acetate to improve recovery. For further sample cleanup with solid-phase extraction (SPE), the HLB SPE cartridge was chosen after comparing with several other types of SPE cartridges. High-performance liquid chromatography was performed on a multimode column for proper retention and separation of highly polar and water-soluble patulin from sample interferences. Sample extracts were analyzed by LC/MS/MS with electrospray ionization in negative ion mode with selected reaction monitoring of patulin and (13)C7-patulin at m/z 153→m/z 109 and m/z 160→m/z 115, respectively. The validity of the method was tested by measuring gravimetrically fortified samples of various apple products. In addition, the repeatability and the reproducibility of the method were tested to evaluate the performance of the method. The method was shown to provide accurate measurements in the 3-40 µg/kg range with a relative expanded uncertainty of around 1%.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Malus/química , Malus/microbiologia , Micotoxinas/análise , Patulina/análise , Espectrometria de Massas em Tandem/métodos , Bebidas/análise , Microbiologia de Alimentos , Frutas/química , Frutas/microbiologia , Fungos/química , Limite de Detecção , Reprodutibilidade dos Testes
20.
J Chromatogr A ; 1711: 464454, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37871502

RESUMO

Phthalates are mainly used as plasticizers in polyvinyl chloride (PVC). However, prolonged exposure to phthalates poses considerable risks to human health. Consequently, the utilization of phthalates in consumer products is subject to regulations, with a defined threshold of 0.1 %. In this study, we developed an accurate and simultaneous method for determination of 11 representative phthalates and a non-phthalate plasticizer (di(2-ethylhexyl) terephthalate, DEHT) in PVC as a higher-order reference method. Homogeneously prepared PVC samples, each containing approximately 0.1 % of the target plasticizer compounds, were analyzed using gas chromatography-mass spectrometry (GC-MS) with deuterium-labeled phthalates and DEHT. The developed method could effectively separate and quantify all target plasticizers without interference with each other and potential overlap between the isomeric forms of phthalates, di-isodecyl phthalate, and di-isononyl phthalate. The developed method has high-order metrological quality, exhibiting exceptional selectivity, accuracy, repeatability (≤ 2.17 %), reproducibility (≤ 2.16 %), and relative expanded uncertainty (≤ 5.6 %). This analytical method is thus suitable for accurately assessing the target plasticizer levels in PVC products for ensuring compliance with the established 0.1 % threshold. This method was successfully applied to quantify twelve distinct plasticizers in PVC products obtained from the Korean market, validating its effectiveness and reliability in real-world scenarios.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Humanos , Plastificantes/análise , Cloreto de Polivinila/química , Reprodutibilidade dos Testes , Ácidos Ftálicos/análise , Espectrometria de Massas , Cromatografia Gasosa-Espectrometria de Massas/métodos , Isótopos , Dietilexilftalato/análise
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