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1.
Langenbecks Arch Surg ; 407(6): 2273-2279, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35551467

RESUMO

BACKGROUND: The standard treatment for pT3N0 gastric cancer (GC) in Japanese guidelines is radical surgery without adjuvant chemotherapy. However, certain percentages of these patients develop recurrences; therefore, detecting the high-risk subgroup of recurrence may contribute to improve patient's outcome by adjuvant chemotherapy. In this study, we aimed to identify a predictive indicator of poor prognosis in pT3N0 GC. METHODS: Eighty-one patients who were diagnosed as pT3N0 GC after curative surgical resection and had not received adjuvant chemotherapy were included. The clinicopathological factors and laboratory parameters were evaluated by univariate and multivariate analyses to identify prognostic factors of tumor recurrence. Survival analysis was performed by Kaplan-Meier method. RESULTS: Male (P = 0.027), a high body mass index (BMI) (P = 0.031), a high CA19-9 value (P = 0.025), and a lower number of retrieved lymph nodes (P = 0.018) were found to be significantly associated with a shorter recurrence free survival (RFS). In a multivariate analysis, high CA19-9 value (> 37 U/ml) [(hazard ratio (HR): 3.326; 95% confidence interval (CI): 1.044 to 10.596; P = 0.042] was found to be an independent predictor of RFS. CONCLUSION: The preoperative high CA19-9 value is considered a useful prognostic marker for predicting cancer recurrence after curative surgery in pT3N0 GC patients. For those patients, adjuvant chemotherapy might be considered to improve the survival outcome.


Assuntos
Antígeno CA-19-9 , Neoplasias Gástricas , Quimioterapia Adjuvante/métodos , Humanos , Masculino , Recidiva Local de Neoplasia/cirurgia , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/patologia
2.
Appl Opt ; 59(3): 742-747, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32225203

RESUMO

We fabricated a binary diffractive lens to control focal distribution, such as intensity distribution, by controlling the focal length and depth of focus. The results revealed changes in the focal length and depth of focus as a function of changes in the ring zone interval ΔRM at the end of the lens. Similar results were obtained from experiments. The peak position on the optical axis shifts further away from the lens. The half-width in the propagation direction increases with the ΔRM. These results demonstrate the possibility of controlling the focal distribution using single flat lenses by changing the periodic structure.

3.
Gan To Kagaku Ryoho ; 43(12): 1875-1877, 2016 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-28133161

RESUMO

A 69-year-old man underwent esophagogastroduodenoscopy, which showed a slightly depressed lesion at the greater curvature of the gastric body. We diagnosed gastric adenocarcinoma of the fundic gland type(GA-FG)from examination of the biopsy specimen. Endoscopic submucosal dissection(ESD)was performed for curative resection. The pathological examination revealed a positive vertical margin. Consequently, laparoscopic gastrectomy was additionally performed. GA-FG has recently been proposed as a new entity of gastric adenocarcinoma. GA-FG mostly develops without Helicobacter pylori infection and often invades the submucosa, regardless of size. However, GA-FG rarely demonstrates lymphatic and venous invasion despite deep submucosal invasion. Since most GA-FG cases undergo ESD, few reports of surgical resection exist. Here, we report our experience of laparoscopic gastrectomy for GA-FG.


Assuntos
Adenocarcinoma/cirurgia , Neoplasias Gástricas/cirurgia , Idoso , Biópsia , Gastrectomia , Humanos , Laparoscopia , Masculino , Neoplasias Gástricas/patologia , Resultado do Tratamento
4.
J Am Chem Soc ; 134(15): 6584-95, 2012 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-22468558

RESUMO

The negative ion chemistry of five azine molecules has been investigated using the combined experimental techniques of negative ion photoelectron spectroscopy to obtain electron affinities (EA) and tandem flowing afterglow-selected ion tube (FA-SIFT) mass spectrometry to obtain deprotonation enthalpies (Δ(acid)H(298)). The measured Δ(acid)H(298) for the most acidic site of each azine species is combined with the EA of the corresponding radical in a thermochemical cycle to determine the corresponding C-H bond dissociation energy (BDE). The site-specific C-H BDE values of pyridine, 1,2-diazine, 1,3-diazine, 1,4-diazine, and 1,3,5-triazine are 110.4 ± 2.0, 111.3 ± 0.7, 113.4 ± 0.7, 107.5 ± 0.4, and 107.8 ± 0.7 kcal mol(-1), respectively. The application of complementary experimental methods, along with quantum chemical calculations, to a series of nitrogen-substituted azines sheds light on the influence of nitrogen atom substitution on the strength of C-H bonds in six-membered rings.

5.
Hinyokika Kiyo ; 58(8): 395-9, 2012 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-23052261

RESUMO

To determine the follow-up schedule in patients with non-muscle-invasive bladder cancer who had remained recurrence-free for 5 or more years, we retrospectively reviewed 258 patients with Ta and T1 bladder cancer who had been free of recurrence for at least 5 years. Of these 258 patients, subsequent recurrences developed in 100 patients. In spite of our recommendation that cystoscopic follow-up be done at 12-month intervals for patients who remained recurrence-free for more than 5 years, 45 had been followed at intervals of more than 12 months (range, 13-77 months) when the recurrences were found. Of 100 recurrent tumors, 20 (20.0%) showed bladder muscle invasion. Muscle-invasive cancer was identified more often in the patients with cytoscopic intervals of more than 12 months than in those of less than 12 months (35.6% versus 7.3%). Therefore, we recommend that cystoscopy be performed at intervals of less than 12 months in patients with non-muscle invasive bladder cancer for recurrence detection before tumors become muscle invasive, even when patients remain free of recurrence for a long period.


Assuntos
Neoplasias da Bexiga Urinária/mortalidade , Cistoscopia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Neoplasias da Bexiga Urinária/patologia
6.
Hinyokika Kiyo ; 56(9): 535-8, 2010 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-20940532

RESUMO

Leiomyosarcoma is a malignant soft-tissue cancer arising from tissues containing smooth muscle. It commonly occurs in the gastrointestinal system and retroperitoneum, but is rare in the genito-urinary system. We experienced a case of primary testicular leiomyosarcoma. A 71-year-old man presented with painless swelling of the right scrotal contents for 4 months. A high orchiectomy was performed. Histological examination revealed primary testicular leiomyosarcoma. The patient did not receive any adjuvant therapy. Seven months after the operation, there has been no recurrence. Cases of primary intratesticular leiomyosarcoma are rare. To the best of our knowledge, only sixteen cases have been reported in the literature.


Assuntos
Leiomiossarcoma/patologia , Neoplasias Testiculares/patologia , Idoso , Humanos , Masculino
7.
J Phys Chem B ; 112(2): 545-57, 2008 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-17960930

RESUMO

A combination of experimental methods, photoelectron-imaging spectroscopy, flowing afterglow-photoelectron spectroscopy and the flowing afterglow-selected ion flow tube technique, and electronic structure calculations at the B3LYP/6-311++G(d,p) level of density functional theory (DFT) have been employed to study the mechanism of the reaction of the hydroxide ion (HO-) with 1H-1,2,3-triazole. Four different product ion species have been identified experimentally, and the DFT calculations suggest that deprotonation by HO- at all sites of the triazole takes place to yield these products. Deprotonation of 1H-1,2,3-triazole at the N1-H site gives the major product ion, the 1,2,3-triazolide ion. The 335 nm photoelectron-imaging spectrum of the ion has been measured. The electron affinity (EA) of the 1,2,3-triazolyl radical has been determined to be 3.447 +/- 0.004 eV. This EA and the gas-phase acidity of 2H-1,2,3-triazole are combined in a negative ion thermochemical cycle to determine the N-H bond dissociation energy of 2H-1,2,3-triazole to be 112.2 +/- 0.6 kcal mol-1. The 363.8 nm photoelectron spectroscopic measurements have identified the other three product ions. Deprotonation of 1H-1,2,3-triazole at the C5 position initiates fragmentation of the ring structure to yield a minor product, the ketenimine anion. Another minor product, the iminodiazomethyl anion, is generated by deprotonation of 1H-1,2,3-triazole at the C4 position, followed by N1-N2 bond fission. Formation of the other minor product, the 2H-1,2,3-triazol-4-ide ion, can be rationalized by initial deprotonation of 1H-1,2,3-triazole at the N1-H site and subsequent proton exchanges within the ion-molecule complex. The EA of the 2H-1,2,3-triazol-4-yl radical is 1.865 +/- 0.004 eV.

8.
J Phys Chem A ; 112(39): 9516-25, 2008 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-18570357

RESUMO

The E(CO)2 elimination reactions of alkyl hydroperoxides proceed via abstraction of an alpha-hydrogen by a base: X(-) + R(1)R(2)HCOOH --> HX + R(1)R(2)C=O + HO(-). Efficiencies and product distributions for the reactions of the hydroxide anion with methyl, ethyl, and tert-butyl hydroperoxides are studied in the gas phase. On the basis of experiments using three isotopic analogues, HO(-) + CH3OOH, HO(-) + CD3OOH, and H(18)O(-) + CH3OOH, the overall intrinsic reaction efficiency is determined to be 80% or greater. The E(CO)2 decomposition is facile for these methylperoxide reactions, and predominates over competing proton transfer at the hydroperoxide moiety. The CH3CH2OOH reaction displays a similar E(CO)2 reactivity, whereas proton transfer and the formation of HOO(-) are the exclusive pathways observed for (CH3)3COOH, which has no alpha-hydrogen. All results are consistent with the E(CO)2 mechanism, transition state structure, and reaction energy diagrams calculated using the hybrid density functional B3LYP approach. Isotope labeling for HO(-) + CH3OOH also reveals some interaction between H2O and HO(-) within the E(CO)2 product complex [H2O...CH2=O...HO(-)]. There is little evidence, however, for the formation of the most exothermic products H2O + CH2(OH)O(-), which would arise from nucleophilic condensation of CH2=O and HO(-). The results suggest that the product dynamics are not totally statistical but are rather direct after the E(CO)2 transition state. The larger HO(-) + CH3CH2OOH system displays more statistical behavior during complex dissociation.

9.
J Phys Chem A ; 112(40): 9723-30, 2008 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-18774783

RESUMO

The 363.8 nm photoelectron spectrum of the iminodiazomethyl anion has been measured. The anion is synthesized through the reaction of the hydroxide ion (HO-) with 1 H-1,2,3-triazole in helium buffer gas in a flowing afterglow ion source. The observed spectrum exhibits well-resolved vibronic structure of the iminodiazomethyl radical. Electronic structure calculations have been performed at the B3LYP/6-311++G(d,p) level of theory to study the molecular structure of the ion. Equilibrium geometries of four possible conformers of the iminodiazomethyl anion have been obtained from the calculations. Spectral simulations have been performed on the basis of the calculated geometries and normal modes of these conformationally isomeric ions and the corresponding radicals. The spectral analysis suggests that the ions of two conformations are primarily formed in the aforementioned reaction. The relative abundance of the two conformers substantially deviates from the thermal equilibrium populations, and it reflects the potential energy surfaces relevant to conformational isomerization processes. The electron affinities of the ( ZE)- and ( EE)-iminodiazomethyl radicals have been determined to be 2.484 +/- 0.007 and 2.460 +/- 0.007 eV, respectively. The energetics of the iminodiazomethyl anion is compared with that of the most stable structural isomer, the 1,2,3-triazolide ion. Collision-induced dissociation of the 1,2,3-triazolide ion has also been studied in flowing afterglow-selected ion flow tube experiments. Facile fragmentation generating a product ion of m/ z 40 has been observed. DFT calculations suggest that fragmentation of the 1,2,3-triazolide ion to the cyanomethyl anion and N2 is exothermic. The stability of the ion is discussed in comparison with other azolide ions with different numbers of N atoms in the five-membered ring.

10.
Hinyokika Kiyo ; 54(8): 573-5, 2008 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-18788451

RESUMO

We present a case of isolated adrenocorticotrophic hormone (ACTH) deficiency (IAD) in a late onset hypogonadism (LOH) clinic, not diagnosed by examinations in internal medicine. A 54-year-old man showed body weight loss with severe appetite loss, general malaise and hypotension. He visited our clinic for a checkup for LOH after general examinations in internal medicine. His hormonal examination showed undetectable ACTH and cortisol levels. However, the values of other pituitary hormones and testosterone were normal. A load test for anterior pituitary hormone (CRH + TRH + LHRH + GRH test) revealed that the ACTH-cortisol system showed no response although the other pituitary hormones responded. These findings confirmed the diagnosis of isolated ACTH deficiency. Administration of hydrocortisone dramatically improved his symptoms. Symptoms of IAD are similar to those of LOH syndrome and depression. Thus, we should consider IAD as one of the differential diagnoses in LOH clinics.


Assuntos
Hormônio Adrenocorticotrópico/deficiência , Hipogonadismo/diagnóstico , Hipogonadismo/etiologia , Andropausa , Diagnóstico Diferencial , Humanos , Hidrocortisona/administração & dosagem , Hidrocortisona/deficiência , Hipogonadismo/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
11.
J Am Soc Mass Spectrom ; 18(6): 1046-51, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17448673

RESUMO

This work describes the first experimental studies of deuterium kinetic isotope effects (KIEs) for the gas-phase E2 reactions of microsolvated systems. The reactions of F(-)(H(2)O)(n) and OH(-)(H(2)O)(n), where n = 0, 1, with (CH(3))(3)CX (X = Cl, Br), as well as the deuterated analogs of the ionic and neutral reactants, were studied utilizing the flowing afterglow-selected ion flow tube technique. The E2 reactivity is found to decrease with solvation. Small, normal kinetic isotope effects are observed for the deuteration of the alkyl halide, while moderately inverse kinetic isotope effects are observed for the deuteration of the solvent. Minimal clustering of the product ions is observed, but there are intriguing differences in the nature and extent of the clustering process. Electronic structure calculations of the transition states provide qualitative insight into these microsolvated E2 reactions.


Assuntos
Deutério/química , Gases/química , Solventes/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Marcação por Isótopo/métodos , Cinética , Transição de Fase
12.
Reprod Med Biol ; 5(1): 37-41, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29699234

RESUMO

Aim: The objective of the present study was to measure serum free and total testosterone values using the radioimmunoassay (RIA) method in healthy Japanese male volunteers with no current diseases. Methods: Two hundred and fifty-one healthy men who had no medical illness and received no current medical treatment were selected from 405 male volunteers. Free and total testosterone were measured in blood samples using the RIA method. Results: Free but not total testosterone significantly decreased with age. Mean free testosterone values from morning blood samples for each age decade from the 20s to the 70s were 17.0, 14.6, 12.5, 10.6, 8.9 and 8.5 pg/mL, respectively. Mean total testosterone values from morning blood samples for each age decade from the 20s to the 70s were 4.7, 4.2, 4.4, 4.2, 4.2, 4.0 and 4.0 ng/mL, respectively. The rates of healthy volunteers that fell within the standard reference ranges for free and total testosterone were 97% and 97%, respectively. However, 19% of the total testosterone values were considered to indicate hypogonadism according to the International Society for the Study of the Aging Male (ISSAM) criteria (<3.17 ng/mL). Conclusions: Our data corresponded to the standard reference ranges of Japanese men but not the ISSAM criteria. It may be more appropriate to establish a standard reference range for serum testosterone for individual countries. (Reprod Med Biol 2006; 5: 37-41).

13.
Hinyokika Kiyo ; 52(12): 903-9, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17252970

RESUMO

The goal of this study is to compare surgical and oncological outcomes of laparoscopic nephroureterectomy and the open surgery using the concept of systemic inflammatory response syndrome (SIRS) in addition to common variables. Thirty-six and 23 patients having upper urinary tract urothelial cancer who were operated on with retroperitoneoscopic hand-assisted nephroureterectomy (RHANU) or standard open nephroureterectomy (ONU) retrospectively, were analyzed. Median operation time was 140 (range 70-200) and 60 (range 45-85) minutes, respectively in the RHANU group and the ONU group. The median days to ambulation and hospital stay of the RHANU group were significantly shorter than those of the ONU group. There was no significant difference in the incidence of SIRS and other surgical results between the two groups. In oncological outcome, no significant difference was found in the bladder recurrence rate (RHANU vs. ONU; 52% vs. 45%), local recurrence (0% vs. 0%), distant metastasis (11% vs. 13%) or survival rate (94% vs. 91%) between the RHANU group and the ONU group at 2-year follow-up. There was no port site recurrence in the RHANU group. Although the RHANU may have an advantage in terms of earlier recovery, there were no significant differences in the incidence of SIRS and oncological outcomes between the RHANU group and the ONU group.


Assuntos
Laparoscopia , Nefrectomia/métodos , Espaço Retroperitoneal , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Ureter/cirurgia , Neoplasias Urológicas/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia , Complicações Pós-Operatórias , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Neoplasias Urológicas/mortalidade
14.
Circulation ; 109(22): 2761-5, 2004 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-15148272

RESUMO

BACKGROUND: Thrombin plays a crucial role in atherothrombotic changes. Because heparin cofactor II (HCII) inhibits thrombin actions after binding to dermatan sulfate at injured arterial walls, HCII may negatively regulate thrombin actions in vascular walls. We hypothesized that plasma HCII activity is a preventive factor against atherosclerotic changes, especially in elderly individuals who already have atherosclerotic vascular injuries. METHODS AND RESULTS: Maximum plaque thickness (MPT) in the carotid artery was measured by ultrasonography in 306 Japanese elderly individuals (154 men and 152 women; age, 40 to 91 years; 68.9+/-11.1 years, mean+/-SD). The relevance of cardiovascular risk factors including plasma HCII activity to the severity of MPT was statistically evaluated. Plasma HCII activity decreased with age. Simple linear regression analysis after adjustments for age and sex showed that lipoprotein(a), glycosylated hemoglobin A1c, and presence of diabetes mellitus significantly contributed to an increase in MPT values (r=0.119, P<0.05; r=0.196, P<0.001; and r=0.227, P<0.0001, respectively). In contrast, high-density lipoprotein (HDL) cholesterol and HCII activity were negatively correlated with MPT values (r=-0.117, P<0.05, and r=-0.202, P<0.0005, respectively). Multiple regression analysis revealed that plasma HCII activity and HDL cholesterol independently contributed to the suppression of MPT values and that the antiatherogenic contribution of HCII activity was stronger than that of HDL cholesterol (P<0.001 and P<0.05, respectively). CONCLUSIONS: These results suggest that HCII can be a novel and independent antiatherogenic factor. Moreover, HCII is a stronger predictive factor than HDL cholesterol against carotid atherosclerosis in elderly individuals.


Assuntos
Doenças das Artérias Carótidas/sangue , Cofator II da Heparina/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/sangue , Antitrombinas/análise , Doenças Cardiovasculares/sangue , Doenças das Artérias Carótidas/diagnóstico por imagem , Feminino , Cofator II da Heparina/análise , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco , Índice de Gravidade de Doença , Ultrassonografia
15.
ACS Nano ; 9(3): 3206-14, 2015 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-25738973

RESUMO

Manipulation of individual graphene sheets/films into specific architectures at macroscopic scales is crucially important for practical uses of graphene. We present herein a versatile and robust method based on annealing of solid carbon precursors on nickel templates and thermo-assisted removal of poly(methyl methacrylate) under low vacuum of ∼0.6 Pa for fabrication of macroscopic, freestanding, and tubular graphene (TG) architectures. Specifically, the TG architectures can be obtained as individual and woven tubes with a diameter of ∼50 µm, a wall thickness in the range of 2.1-2.9 nm, a density of ∼1.53 mg·cm(-3), a thermal stability up to 600 °C in air, an electrical conductivity of ∼1.48 × 10(6) S·m(-1), and field emission current densities on the order of 10(4) A·cm(-2) at low applied electrical fields of 0.6-0.7 V·µm(-1). These properties show great promise for applications in flexible and lightweight electronics, electron guns, or X-ray tube sources.

16.
J Bone Miner Res ; 18(8): 1461-70, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12929935

RESUMO

UNLABELLED: Expression of an osteogenic cytokine, IL-11, is decreased in SAMP6. We show here that IL-11 transcription largely depends on AP-1 transcription factors, activities of which are decreased in SAMP6 as well as aged ICR mice. Therefore, diminished AP-1 activity and the resultant decline in IL-11 expression may play a role in impaired bone formation in the aged. INTRODUCTION: Evidence suggests that impaired osteoblastogenesis contributes to aging-associated osteopenia. The P6 strain of senescence-accelerated mice (SAM) is an animal model of senile osteoporosis, which exhibits low bone mass caused by impaired bone formation. Bone marrow stromal cells from SAMP6 show decreased osteoblastogenesis and increased adipogenesis. We previously demonstrated that these abnormalities of SAMP6 stromal cells may be attributed to decreased expression of interleukin (IL)-11. METHODS: In this study, we attempted to determine the molecular mechanism of decreased IL-11 expression by SAMP6 stromal cells by cloning and analyzing the mouse IL-11 gene promoter. RESULTS AND CONCLUSIONS: We found that two tandem activating protein-1 (AP-1) sites that reside immediately upstream of TATA box play critical roles in IL-11 gene transcription. Gel shift analysis showed that binding activity to the IL-11 AP-1 sites was reduced in SAMP6 stromal cell nuclear extracts. Among multiple components of AP-1 transcription factors, Jun D binding was particularly decreased. Furthermore, decreased Jun D binding and IL-11 expression by stromal cells was also observed in aged mice of the ICR strain. Therefore, decreased AP-1 activity and a resultant decline in IL-11 expression by bone marrow stromal cells may play a role in impaired bone formation in the aged.


Assuntos
Envelhecimento/fisiologia , Células da Medula Óssea/metabolismo , Interleucina-11/genética , Interleucina-11/metabolismo , Osteogênese/fisiologia , Células Estromais/metabolismo , Fator de Transcrição AP-1/metabolismo , Regiões 5' não Traduzidas/genética , Envelhecimento/genética , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Regulação da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos ICR , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Ligação Proteica , Proteínas Proto-Oncogênicas c-jun/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência
17.
Biotechnol Prog ; 19(4): 1355-64, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12892502

RESUMO

Chemical-ionization mass spectrometry (CIMS) using flow reactors is an emerging method for on-line monitoring of trace concentrations of organic compounds in the gas phase. In this study, a flow-reactor CIMS instrument, employing the H(3)O(+) cation as the ionizing reagent, was used to simultaneously monitor several volatile metabolic products as they are released into the headspace during bacterial growth in a bioreactor. Production of acetaldehyde, ethanol, acetone, butanol, acetoin, diacetyl, and isoprene by Bacillus subtilis is reported. Ion signal intensities were related to solution-phase concentrations using empirical calibrations and, in the case of isoprene, were compared with simultaneous gas chromatography measurements. Identification of volatile and semivolatile metabolites is discussed. Flow-reactor CIMS techniques should be useful for bioprocess monitoring applications because of their ability to sensitively and simultaneously monitor many volatile metabolites on-line.


Assuntos
Acetoína/metabolismo , Bacillus subtilis/crescimento & desenvolvimento , Bacillus subtilis/metabolismo , Reatores Biológicos/microbiologia , Butadienos/metabolismo , Técnicas de Cultura de Células/instrumentação , Análise de Injeção de Fluxo/instrumentação , Hemiterpenos/metabolismo , Espectrometria de Massas/instrumentação , Pentanos/metabolismo , Técnicas de Cultura de Células/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Estudos de Viabilidade , Análise de Injeção de Fluxo/métodos , Espectrometria de Massas/métodos , Sistemas On-Line , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Eur J Mass Spectrom (Chichester) ; 10(2): 225-31, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15103100

RESUMO

Gas-phase reactions of nitromethane (1), nitroethane (2), 2-nitropropane (3), 2-methyl-2-nitropropane (4) and nitrocyclopropane (5) were studied at 300 K using the flowing afterglow technique. These nitroalkanes react with gas-phase bases HO(-), CH(3)O(-) and HOO(-) very rapidly with rate coefficients of (2.5-4.3) x 10(-9) cm(3) s(-1) and reaction efficiencies of 60-100%, for example, k = 3.2 x 10(-9) cm(3) s(-1) (86%) for 5 reacting with hydroperoxide anion. Proton transfer (PT) is the only reaction observed for 1 while elimination (E2) is the exclusive pathway for 4 yielding isobutene and NO(2)(-). Both PT and E2 reactions are observed for 2, 3 and 5, the former being the major pathway. Deprotonated anions of 1, 2, 3 and 5 were subjected to reactivity studies with CH(3)I, CO(2), CS(2) and SO(2). Nucleophilic substitution (S(N)2) reaction occurs with CH(3)I while characteristic products CS(2)O(-) and SO(3)(-) are formed from CS(2) and SO(2), respectively, along with competing adduct formation. The SN(2) rate is greater, whereas the reactivities with the triatomic reagents are smaller for deprotonated nitrocyclopropane than for the other acyclic anions. These observations strongly suggest that the reactions of nitroalkane [M - H](-) anions occur through initial attack from the terminal oxygen; the nitrocyclopropane carbanion is more strained and, thus, less stabilized by resonance [R(2)C(-) - NO2 <--> R(2)=NO(2)(-)] resulting in the greater basicity/nucleophilicy and the less negative charge on the oxygen site.

19.
Kaku Igaku ; 40(1): 17-22, 2003 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-12701203

RESUMO

A 69-year-old woman presented with dyspnea on exertion. Echocardiography showed dilatation and diffuse hypokinesis of the left ventricle. 99mTc-tetrofosmin myocardial SPECT showed moderately reduced uptake in the anteroseptal wall and the inferior wall on the rest images, but was improved on the ATP loading images. 123I-BMIPP myocardial SPECT showed severely reduced uptake in the anterior wall and the inferior wall. These SPECT findings suggested ischemic heart disease rather than dilated cardiomyopathy. Coronary angiography showed no organic stenosis, but diffuse coronary ectasia was noted in three vessels. Intravascular ultrasound revealed remarkable coronary ectasia, with a maximal diameter of 8.2 mm. Coronary flow velocity as measured by Doppler blood flow guide wire was remarkably reduced. Coronary spasms were not provocated by ergonovine loading test. These findings suggested that microvascular thrombi and disturbance of dilatation caused myocardial ischemia in this patient. We treated the patient with ticlopidine and nicorandil. Following treatment left ventricle wall motion, 99mTc-tetrofosmin and 123I-BMIPP myocardial SPECT findings were improved.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Vasos Coronários/patologia , Coração/diagnóstico por imagem , Idoso , Doença das Coronárias/fisiopatologia , Dilatação Patológica , Ácidos Graxos , Feminino , Humanos , Radioisótopos do Iodo , Iodobenzenos , Microcirculação/diagnóstico por imagem , Microcirculação/patologia , Compostos Organofosforados , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único
20.
Kaku Igaku ; 40(1): 11-6, 2003 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-12701202

RESUMO

We reported a case of a 72-year-old man with chest pain. An electrocardiogram showed ST segment elevation in I, II, III, aVL, aVF and V1-6 leads. 99mTc-tetrofosmin myocardial SPECT showed defect in the anterior, septal, apical and inferior walls. Coronary angiography showed 99% stenosis of the proximal right coronary artery and total occlusion of the midsegment of the left anterior descending coronary artery. Therefore, direct PTCA was performed for each lesion to achieve reperfusion. We didnt's see reperfusion injury during PTCA of the left coronary artery. On the other side, we saw severe reperfusion injury, such as slow-flow, arrhythmia and falling blood pressure during PTCA of the right coronary artery. After four hours, 99mTc-PYP myocardial SPECT showed marked uptake in the apical and inferior walls, and mild uptake in the anterior and posterior walls. After three days, severely-reduced uptake of 99mTc-PYP in the apex was noted, and mild uptake in the mid-portion of the anterior wall and the mid-portion of the inferior wall. Though reperfusion injury was seen, three was mild myocardial uptake of 99mTc-PYP in the area of the right coronary artery. On the other side, despite no reperfusion injury, there showed marked uptake during the acute phase and defect during the subacute phase in the area of the left coronary artery. Wall motion of the left ventricle was normal in the area of the right coronary artery and akinesis was seen on the left. These findings suggest that 99mTc-tetrofosmin and 99mTc-PYP myocardial SPECT are useful for visualization of reperfusion injury during the acute phase and for estimation of function during the chronic phase, better even than electrocardiogram or coronary angiography.


Assuntos
Infarto do Miocárdio/diagnóstico por imagem , Traumatismo por Reperfusão Miocárdica/diagnóstico por imagem , Compostos Radiofarmacêuticos , Pirofosfato de Tecnécio Tc 99m , Reação de Fase Aguda , Idoso , Angioplastia Coronária com Balão , Humanos , Masculino , Infarto do Miocárdio/terapia , Cintilografia
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