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1.
Nanoscale ; 12(43): 22234-22244, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33141137

RESUMO

We find that the use of Au substrate allows fast, self-limited WS2 monolayer growth using a simple sequential exposure pattern of low cost, low toxicity precursors, namely tungsten hexacarbonyl and dimethylsulfide (DMS). We use this model reaction system to fingerprint the technologically important metal organic chemical vapour deposition process by operando X-ray photoelectron spectroscopy (XPS) to address the current lack of understanding of the underlying fundamental growth mechanisms for WS2 and related transition metal dichalcogenides. Au effectively promotes the sulfidation of W with simple organosulfides, enabling WS2 growth with low DMS pressure (<1 mbar) and a suppression of carbon contamination of as-grown WS2, which to date has been a major challenge with this precursor chemistry. Full WS2 coverage can be achieved by one exposure cycle of 10 minutes at 700 °C. We discuss our findings in the wider context of previous literature on heterogeneous catalysis, 2D crystal growth, and overlapping process technologies such as atomic layer deposition (ALD) and direct metal conversion, linking to future integrated manufacturing processes for transition metal dichalcogenide layers.

2.
Oncol Lett ; 16(6): 7223-7230, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30546460

RESUMO

Breast cancer (BC) is the most frequently diagnosed malignant tumor in women worldwide, and the development of new molecules associated with BC is essential for the management of this disease. RAS and EF-hand domain-containing (RASEF) encodes the GTPase enzyme that belongs to the Rab family. Although the effects of this gene have been reported in several malignant tumor types, the role of RASEF in BC has not been completely elucidated. The aim of the present study was to investigate the importance of RASEF expression in BC. RASEF mRNA expression levels were evaluated in BC and non-cancerous mammary cell lines. The association between RASEF mRNA expression levels and clinicopathological factors in 167 patients with BC were then determined. Among the 13 examined BC cell lines, ER-negative/HER2-negative cell lines expressed lower RASEF mRNA levels, when compared with the other examined cell lines (P=0.014). Of the 167 patients examined, patients with negative hormone receptor status exhibited significantly lower RASEF mRNA expression levels (P<0.001). In addition low RASEF expression in BC tissues was associated with negative estrogen receptor status (P<0.001), negative progesterone receptor status (P<0.001), and triple-negative status (P<0.001). Additionally, although the differences were not statistically significant, patients with low RASEF expression levels exhibited poorer disease-free survival (P=0.123) and overall survival (P=0.086) than other patients. The results of the present study indicate that RASEF mRNA expression levels are associated with hormone receptor status in BC.

3.
Angew Chem Int Ed Engl ; 57(33): 10595-10599, 2018 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-29888857

RESUMO

Hydrogenases (H2 ases) are benchmark electrocatalysts for H2 production, both in biology and (photo)catalysis in vitro. We report the tailoring of a p-type Si photocathode for optimal loading and wiring of H2 ase through the introduction of a hierarchical inverse opal (IO) TiO2 interlayer. This proton-reducing Si|IO-TiO2 |H2 ase photocathode is capable of driving overall water splitting in combination with a photoanode. We demonstrate unassisted (bias-free) water splitting by wiring Si|IO-TiO2 |H2 ase to a modified BiVO4 photoanode in a photoelectrochemical (PEC) cell during several hours of irradiation. Connecting the Si|IO-TiO2 |H2 ase to a photosystem II (PSII) photoanode provides proof of concept for an engineered Z-scheme that replaces the non-complementary, natural light absorber photosystem I with a complementary abiotic silicon photocathode.


Assuntos
Hidrogenase/metabolismo , Energia Solar , Água/metabolismo , Bismuto/química , Técnicas Eletroquímicas , Eletrodos , Hidrogênio/metabolismo , Luz , Processos Fotoquímicos , Complexo de Proteína do Fotossistema II/química , Complexo de Proteína do Fotossistema II/metabolismo , Técnicas de Microbalança de Cristal de Quartzo , Silício/química , Titânio/química , Vanadatos/química , Água/química
4.
Clin Nucl Med ; 43(7): 482-485, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29688947

RESUMO

BACKGROUND: Age is a prognostic factor for recurrent differentiated thyroid carcinoma (DTC) and may be related to radioactive iodine (RAI) nonavidity. Indications for molecular-targeted drugs (MTDs) are currently limited to RAI-refractory DTC. Demonstrating refractoriness to RAI, mainly indicated by RAI nonavidity, may be a barrier to the introduction of MTDs for elderly patients. The present study was conducted to evaluate the impact of age and histological type on the RAI avidity of recurrent lesions of DTC. METHODS: Two hundred fifty-eight patients (189 patients with classic papillary thyroid carcinoma [cPTC], 8 patients with follicular variant of papillary thyroid carcinoma, and 61 patients with follicular thyroid carcinoma), who underwent their first RAI whole-body scanning for recurrent DTC at our institution between 2004 and 2013, were retrospectively studied. Radioactive iodine uptake was determined by visible uptake by metastatic lesion(s) in a diagnostic RAI-whole-body scan. RESULTS: The prevalence of RAI-avid lung metastases in cPTC indicated a significant, inverse correlation with age (<55 years, 36.2%; ≥55 years, 3%; P < 0.001). By contrast, for follicular thyroid carcinoma, the prevalence of RAI avidity was not influenced by age. Similar tendencies were observed for lymph node metastases. CONCLUSIONS: Radioactive iodine avidity by metastatic lesions of cPTC in elderly patients, especially those older than 55 years, was seldom demonstrated. Adherence to a strategy of restricting MTD administration after confirmation of RAI refractoriness should be revisited for elderly patients. A strategy of omitting RAI treatment should be taken into account when considering age and histological type.


Assuntos
Adenocarcinoma Folicular/radioterapia , Carcinoma Papilar/radioterapia , Radioisótopos do Iodo/uso terapêutico , Neoplasias Pulmonares/epidemiologia , Recidiva Local de Neoplasia/epidemiologia , Compostos Radiofarmacêuticos/uso terapêutico , Neoplasias da Glândula Tireoide/radioterapia , Adenocarcinoma Folicular/diagnóstico por imagem , Adenocarcinoma Folicular/epidemiologia , Adenocarcinoma Folicular/patologia , Adulto , Fatores Etários , Idoso , Carcinoma Papilar/diagnóstico por imagem , Carcinoma Papilar/epidemiologia , Carcinoma Papilar/patologia , Feminino , Humanos , Neoplasias Pulmonares/secundário , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/patologia
5.
Nagoya J Med Sci ; 80(1): 21-28, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29581611

RESUMO

Laparoscopic adrenalectomy is the gold standard procedure for most adrenal tumors. Obesity is considered as a risk factor for surgical complications. This study aimed to evaluate whether obesity affects peri- and postoperative outcomes of transabdominal laparoscopic adrenalectomy using body mass index (BMI). This retrospective study included 98 patients who underwent transabdominal laparoscopic adrenalectomy between January 2011 and December 2016. We divided the patients into 2 groups: non-obese group (BMI < 25 kg/m2) and obese group (BMI ≥ 25 kg/m2). We assessed perioperative outcomes and postoperative complications between the groups. A total of 98 patients were analyzed (70 without obesity and 28 with obesity). There were no significant differences between the non-obese and obese groups regarding operative time (111 vs 107 min; p = 0.795), blood loss (3.5 vs 3.5 ml; p = 0.740), rate of placement of additional trocars (14.3% vs 17.9%; p = 0.657), rate of open conversion (2.6% vs 3.6%; p = 0.853), and postoperative length of hospital stay (6 vs 5 days; p = 0.237). Furthermore, obesity was not a significant risk factor for postoperative complications (postoperative bleeding, wound infection, and pneumonia). There are no significant differences in peri- and postoperative outcomes of transabdominal laparoscopic adrenalectomy in patients with obesity compared with those without obesity. Transabdominal laparoscopic adrenalectomy is feasible and safe for patients with obesity.


Assuntos
Glândulas Suprarrenais/cirurgia , Adrenalectomia/métodos , Laparoscopia/métodos , Obesidade/complicações , Obesidade/cirurgia , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
6.
World J Surg Oncol ; 16(1): 71, 2018 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-29587757

RESUMO

BACKGROUND: Thyroid metastasis of soft tissue sarcoma is very rare, and the diagnosis is especially difficult when only a single lesion is present. CASE PRESENTATION: A 50-year-old man was diagnosed with myxoid liposarcoma of the right thigh and treated with wide resection. Two and a half years after the surgery, a growing low-density area was incidentally observed in the right lobe of his thyroid gland on follow-up chest computed tomography. Fine needle aspiration biopsy was performed twice, and the thyroid mass was suspected of being a sarcoma metastasis. He was treated by hemithyroidectomy, and the lesion was pathologically confirmed as a metastasis of myxoid liposarcoma. CONCLUSION: We experienced single thyroid gland metastasis in patients with myxoid liposarcoma in whom a growing mass is observed in the thyroid gland after radical surgery of the primary site.


Assuntos
Lipossarcoma Mixoide/patologia , Coxa da Perna/patologia , Neoplasias da Glândula Tireoide/secundário , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Coxa da Perna/cirurgia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia
7.
Int J Clin Oncol ; 23(1): 195-200, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28791509

RESUMO

BACKGROUND: Dose-dense chemotherapy consisting of a combination of epirubicin and cyclophosphamide (EC) improves the survival of patients with breast cancer. Although pegfilgrastim was used at a subcutaneous dose of 6.0 mg in a pivotal study of dose-dense EC treatment, pegfilgrastim at a dose of 3.6 mg has been approved in Japan. We have assessed the feasibility of dose-dense EC treatment supported with a 3.6 mg dose of pegfilgrastim by evaluating the relative dose intensity (RDI) and safety of the treatment, together with measuring the pegfilgrastim concentrations remaining on the day of starting the next cycle of chemotherapy. METHODS: Patients with primary breast cancer received a total of 4 cycles of dose-dense EC treatment every 2 weeks, together with a subcutaneous injection of 3.6 mg pegfilgrastim on the day after chemotherapy. The serum granulocyte colony-stimulating factor (G-CSF) concentrations were measured on the 15th day of every chemotherapy cycle. RESULTS: From March 2015 through to July 2016, a total of 51 patients (median age 51 years; range 33-73 years) were studied. The mean RDI was 95.2% (range 60.0-100%). Although most adverse events were consistent with those reported in previous studies, pneumocystis pneumonia developed in two patients during the following course of docetaxel treatment. The median serum G-CSF concentration was 92.5 (range 30.4-440) pg/ml. CONCLUSIONS: With support provided by pegfilgrastim injection at a dose of 3.6 mg, dose-dense EC is feasible and associated with maintenance of a high RDI. There was no clinically significant accumulation of serum G-CSF concentrations associated with the use of a 3.6 mg dose of pegfilgrastim at 2-week intervals.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Ciclofosfamida/administração & dosagem , Docetaxel , Relação Dose-Resposta a Droga , Esquema de Medicação , Epirubicina/administração & dosagem , Feminino , Filgrastim/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/sangue , Humanos , Japão , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Estudos Prospectivos , Taxoides/administração & dosagem , Resultado do Tratamento
8.
Surg Case Rep ; 3(1): 131, 2017 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-29282558

RESUMO

BACKGROUND: Recent advance of genetic testing has contributed to the diagnosis of hereditary pheochromocytoma and paraganglioma (PPGL). The clinical characteristics of hereditary PPGL are varying among the types of mutational genes. It is still difficult to specify the pathognomonic symptoms in the case of rare genetic mutations. Here, we report the case of synchronous bilateral pheochromocytomas and paraganglioma with novel MYC associated factor X (MAX) gene mutation. CASE PRESENTATION: A 24-year-old female had hyperhidrosis and hypertension. Her urine test showed high normetanephrine and vanillylmandelic acid. Enhanced computed tomography revealed three enhanced masses in right adrenal gland, left adrenal gland, and left renal hilus. She was diagnosed with PPGL. Because 123I-metaiodobenzylguanidine scintigraphy indicated the accumulations in the left adrenal gland mass and the left renal hilus mass and not in the right adrenal gland mass, we performed laparoscopic left adrenalectomy and extirpation of the left renal hilus mass to preserve the right adrenocortical function. However, her symptoms recurred shortly after the operation presumably due to unveiling of the activity of the right pheochromocytoma. Following right adrenalectomy as the second operation, the catecholamine levels declined to normal range. Her genetic testing indicated the novel germline mutation in MAX gene (c.70_73 del AAAC/p.Lys24fs*40). CONCLUSIONS: MAX germline mutation is recently identified as a rare cause of hereditary PPGL. The deletion mutation in MAX gene in this patient has never reported before. In the case of bilateral pheochromocytomas, the surgical indication should be decided considering each patient's genetic background. Due to the possibility for other types of malignant tumors, close follow-up is essential for MAX mutation carriers.

9.
Oncol Rep ; 38(3): 1760-1766, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28713959

RESUMO

Breast cancer (BC) is the most common malignant tumor among women worldwide. Development of novel molecular targets is important to improve prognosis of BC patients. Derlin 3 (DERL3) gene is a member of derlin family, and its coding protein is critical to the endoplasmic reticulum-associated degradation mechanism. However, its oncological role in breast cancer remains unclear. This study evaluated DERL3 expression and function in BC. We analyzed DERL3 mRNA in 13 BC and two non-cancerous cell lines, and explored effects of DERL3 knockdown on BC proliferation, invasion and migration. We also evaluated correlation of DERL3 mRNA expression levels with clinicopathological factors and prognosis in 167 BC patients. DERL3 mRNA expression was detected in five (38%) BC cell lines. Inhibiting DERL3 expression significantly decreased proliferation and invasion in BC cells. Specimens from patients with lymph node metastasis had higher DERL3 mRNA expression than those without (P=0.030). Patients in the highest quartile for DERL3 mRNA expression (n=42) were more likely to experience shorter overall survival than other patients (P=0.032). These findings indicate that DERL3 promotes malignant phenotype in BC cells. DERL3 may serve as a potential prognostic marker and therapeutic target for BC.


Assuntos
Neoplasias da Mama/genética , Metástase Linfática/genética , Proteínas de Membrana/genética , Biomarcadores Tumorais/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Degradação Associada com o Retículo Endoplasmático/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Metástase Linfática/patologia , Células MCF-7 , Pessoa de Meia-Idade , Fenótipo , Prognóstico , RNA Mensageiro/genética
10.
Oncol Lett ; 13(6): 4334-4340, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28599435

RESUMO

Breast cancer (BC) is the most common malignancy among women. Identifying novel biomarkers to predict prognosis accurately is important in managing this disease. The regulatory factor X1 (RFX1) gene is a member of the regulatory factor X gene family. Its protein reportedly downregulates the proto-oncogene c-myc, but its role in BC has been unclear. In this study, expression and methylation status of RFX1 were determined in BC cell lines. We then evaluated RFX1 mRNA expression levels with regard to clinicopathological factors including postoperative prognosis in 167 patients with BC. Expression of RFX1 was heterogeneous among cell lines, and we found no DNA methylation at the RFX1 promoter region. Patients were categorized into groups with high or low RFX1 expression, based on ratio of RFX1 mRNA expression in BC and adjacent non-cancerous tissues. The high RFX1 group was significantly associated with low T factor (P=0.028), earlier disease stage (P=0.015), positive expression of estrogen receptor (P=0.005) and progesterone receptor (P=0.011), negative expression of human epidermal growth factor receptor 2 (P=0.001). The high RFX1 group experienced more favorable disease-free survival (P=0.007) and overall survival (P=0.013). In multivariate analysis, RFX1 expression was an independent prognostic factor for disease-free survival. Our findings indicate that RFX1 may serve as a prognostic marker for BC.

11.
ACS Appl Mater Interfaces ; 8(44): 30564-30575, 2016 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-27723305

RESUMO

Atomic layer deposition (ALD) of ultrathin aluminum oxide (AlOx) films was systematically studied on supported chemical vapor deposition (CVD) graphene. We show that by extending the precursor residence time, using either a multiple-pulse sequence or a soaking period, ultrathin continuous AlOx films can be achieved directly on graphene using standard H2O and trimethylaluminum (TMA) precursors even at a high deposition temperature of 200 °C, without the use of surfactants or other additional graphene surface modifications. To obtain conformal nucleation, a precursor residence time of >2s is needed, which is not prohibitively long but sufficient to account for the slow adsorption kinetics of the graphene surface. In contrast, a shorter residence time results in heterogeneous nucleation that is preferential to defect/selective sites on the graphene. These findings demonstrate that careful control of the ALD parameter space is imperative in governing the nucleation behavior of AlOx on CVD graphene. We consider our results to have model system character for rational two-dimensional (2D)/non-2D material process integration, relevant also to the interfacing and device integration of the many other emerging 2D materials.

12.
Surg Case Rep ; 1(1): 126, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26943450

RESUMO

Cancer antigen 15-3 (CA15-3) is considered as a marker for breast cancer recurrence. However, we encountered a case where the patient showed postoperative elevation of the CA15-3 level due to pernicious anemia without evidence of breast cancer recurrence. The patient was a 60-year-old postmenopausal woman. She had undergone partial mastectomy and sentinel lymph node biopsy (SLNB) for her T1 left breast cancer. SLNB had indicated no lymph node metastases. The tumor was positive for hormone receptors and negative for human epidermal growth factor receptor 2. Therefore, an aromatase inhibitor and external beam irradiation had been administered as adjuvant therapy. However, the CA15-3 level was found to be elevated at 6 months postoperatively. Although imaging studies did not indicate breast cancer recurrence, CA15-3 levels continued to increase. Based on the findings of blood tests and gastroendoscopy, a diagnosis of pernicious anemia due to vitamin B12 deficiency was finally confirmed at 2 years and 6 months postoperatively. The CA15-3 level returned to normal after vitamin B12 administration. The possibility of pernicious anemia should be considered in cases of postoperative elevated CA15-3 levels with no evidence of recurrence in patients with early breast cancer.

13.
Biointerphases ; 8(1): 5, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24706117

RESUMO

Surfaces consisting of sub micron holes (0.420-0.765 µm) engineered into nanoparticle (12 nm) coatings were examined for marine antifouling behaviour that defines early stage settlement. Immersed surfaces were found to be resistant to a 5-hour attachment assay of Amphora coffeaeformis, a marine organism commonly found in abundance on fouled substrates such as foul-releasing paints and self-polishing coatings. Attachment inhibition was attributed to the accessibility of diatoms to the surface. This was governed by the size and morphology of trapped interfacial air pockets measured in-situ using synchrotron small angle x-ray scattering. Surfaces containing larger pores (0.765 µm) exhibited the highest resistance. Macroscopic wettability via contact angle measurements however remained at 160° and sliding angle of < 5° and was found to be independent of pore size and not indicative of early stage fouling behaviour. The balance of hierarchical nano/micro length scales was critical in defining the early stage stability of biofouling character of the interface.


Assuntos
Diatomáceas/fisiologia , Nanopartículas/química , Incrustação Biológica/prevenção & controle , Propriedades de Superfície , Molhabilidade
14.
Gan To Kagaku Ryoho ; 36(11): 1881-4, 2009 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-19920392

RESUMO

A 64-year-old man underwent long-term chemotherapy for advanced gastric cancer with para-aortic lymph node metastasis (cT3 N3 M0 P0, cStage IV). S-1 (120 mg/day) was orally administered for 14 days and CDDP (60 mg/m2) was administered 10 times by intravenous drip on day 8. Next, paclitaxel (PTX 80 mg/m2) was administered 12 times by intravenous drip on days 1, 8 and 15. After 10 S-1/CDDP courses and 12 paclitaxel courses, the lymph node swelling decreased in size, but the tumor increased. CPT-11 (100 mg/m2) was administered as third-line therapy by intravenous drip on days 1, 8, 15 and 22. A partial response (PR) was obtained after 2 courses, but due to severe pyloric stenosis, a food passage disorder appeared. We performed distal gastrectomy with D2 lymph node dissection. The histological diagnosis revealed a complete disappearance of cancer cells in the stomach and lymph nodes.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/patologia , Antimetabólitos Antineoplásicos/administração & dosagem , Antineoplásicos Fitogênicos/administração & dosagem , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Cisplatino/administração & dosagem , Combinação de Medicamentos , Humanos , Irinotecano , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Ácido Oxônico/administração & dosagem , Paclitaxel/administração & dosagem , Neoplasias Gástricas/patologia , Tegafur/administração & dosagem
15.
Appl Spectrosc ; 59(7): 885-92, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16053559

RESUMO

The infrared spectral characteristics of ten different types of disaccharides (trehalose, kojibiose, nigerose, maltose, isomaltose, trehalulose, sucrose, turanose, maltulose, and palatinose) and five different types of monosaccharides (glucose, mannose, galactose, talose, and fructose) in aqueous solutions (H2O and D2O) were determined. The infrared spectra were collected using the Fourier transform infrared attenuated total reflectance (FT-IR/ATR) method and comparisons between the degrees of absorption band-shift of the saccharide spectra in the H2O solution with those in the D2O solution with respect to the saccharide concentrations were done. The study revealed that the wavenumber shifts in the bands of mono- and disaccharides in the H2O and D2O solutions could be used as an indicator of the level of interaction between the saccharides and water. The study also focused on the glycosidic linkage position and the constituent monosaccharides and found that they have a significant influence on the infrared spectroscopic characterization of disaccharides in an aqueous solution.


Assuntos
Óxido de Deutério/química , Dissacarídeos/análise , Glicosídeos/análise , Monossacarídeos/análise , Refratometria/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Água/química , Misturas Complexas/análise , Misturas Complexas/química , Dissacarídeos/química , Glicosídeos/química , Monossacarídeos/química , Soluções
16.
Bioprocess Biosyst Eng ; 27(2): 115-23, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15578229

RESUMO

A simple, rapid and accurate mid-infrared (MIR) spectroscopic method for simultaneously determining the product (ethanol) content and the nutrient (sugar) content in plant-cell culture media was developed using a Fourier transform infrared (FT-IR) spectrometer equipped with an attenuated total reflectance (ATR) accessory. We assessed the potential of this method by comparing it to a high-performance liquid chromatography (HPLC) method, and using the developed method to measure the ethanol and sugar contents simultaneously in liquid culture media with rice and tabacum cell suspensions, respectively. The experimental results suggest that the sugar consumption and ethanol production behaviors of the plant cell suspensions can be non-destructively and simultaneously monitored using the developed method. Furthermore, the spectroscopic method provided in this study could be developed into a technique that could be used to analyze the overall kinetics of the metabolism of the plant cell suspensions.


Assuntos
Algoritmos , Metabolismo dos Carboidratos , Técnicas de Cultura de Células/métodos , Meios de Cultura/metabolismo , Etanol/metabolismo , Nicotiana/metabolismo , Oryza/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Reatores Biológicos/microbiologia , Carboidratos/análise , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Meios de Cultura/análise , Etanol/análise , Especificidade da Espécie
17.
Appl Spectrosc ; 57(12): 1510-6, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14686773

RESUMO

We determine the pH dependency of the mid-infrared spectra in aqueous solution of the organic dissociative materials in the metabolic pathway: saccharide phosphates (G6P, F6P), adenosine, and its phosphates (ATP, ADP, AMP). The series of molar absorbance spectra for these reagents were obtained in a pH range of about 2 to 11 with a Fourier transform infrared (FT-IR) spectrometer equipped with a horizontal diamond attenuated total reflection (ATR) sampling accessory. We also provide a method of infrared spectral extraction of ionic dissociative materials by performing a linear least-square fitting utilizing the formulas of ionic dissociation equilibrium shift, and we obtain the infrared spectrum of each ionic species of the dissociative materials: G6P-, G6P2-; F6P-, F6P2-; ATP2-, ATP3-, ATP4-; ADP-, ADP2-, ADP3-; AMP, AMP-, AMP2-; and adenosine+, adenosine0. The infrared spectral structure of each ionic species of the dissociative materials in the metabolic pathway are discussed. Additionally, the possibility for a quantification system of the concentrations of the organic dissociative materials in varying pH is suggested.


Assuntos
Metabolismo , Espectrofotometria Infravermelho/métodos , Difosfato de Adenosina/análise , Difosfato de Adenosina/química , Monofosfato de Adenosina/análise , Monofosfato de Adenosina/química , Trifosfato de Adenosina/análise , Trifosfato de Adenosina/química , Frutosefosfatos/análise , Frutosefosfatos/química , Glucose-6-Fosfato/análise , Glucose-6-Fosfato/química , Concentração de Íons de Hidrogênio , Íons/química , Reprodutibilidade dos Testes , Soluções/química
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