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1.
Curr Treat Options Oncol ; 24(12): 1667-1682, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37938504

RESUMO

OPINION STATEMENT: Ovarian carcinosarcoma (OCS), also known as a malignant mixed Müllerian tumour (MMMT), is a rare and aggressive form of cancer that accounts for less than 5% of ovarian cancers. It is characterized by high morbidity and mortality rates, with a median overall survival (OS) of less than 2 years. Several factors, including advancing age, nulliparity, reduced lactation rates, decreased use of oral contraceptive pills, genetic mutations in BRCA (breast cancer) genes, and the use of assisted reproductive technology, may increase the risk of OCS. Poor prognostic factors include an advanced stage at diagnosis, older age, lymph node metastasis, suboptimal surgical cytoreduction, the presence of heterologous features on histopathology, and increased expression of vascular endothelial growth factor (VEGF), tumour protein p53, and p53 alongside Wilms tumour 1 (WT1). The main treatment approach for OCS is cytoreductive surgery followed by platinum-based chemotherapy, although immunotherapy is showing promise. Homologous recombination deficiency (HRD) testing may enhance outcomes by enabling personalized immunotherapy and targeted therapies for specific patient groups, thereby reducing unnecessary side effects and healthcare costs. However, there is currently a lack of standardised treatment regimens for OCS patients, with most studies consisting of case reports and a shortage of suitable comparator groups. This article aims to provide clinicians with information on the epidemiology, risk factors, prognostic factors, and latest therapeutic advancements in OCS.


Assuntos
Carcinossarcoma , Neoplasias Ovarianas , Feminino , Humanos , Proteína Supressora de Tumor p53/genética , Fator A de Crescimento do Endotélio Vascular , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/etiologia , Carcinossarcoma/diagnóstico , Carcinossarcoma/epidemiologia , Carcinossarcoma/etiologia
2.
Curr Issues Mol Biol ; 45(10): 8337-8358, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37886969

RESUMO

Despite current advancements in chemotherapy, immunotherapy and targeted treatments, the potential for major adverse cardiovascular events, regardless of previous cardiac history, persists. Scoring systems, such as the Heart Failure Association-International Cardio-Oncology Society (HFA-ICOS) risk assessment tool, can be utilized to evaluate several factors including prior cardiac history, risk factors and cardiac biomarkers to categorize patients into low, moderate, high, and very high-risk groups. Common cardiotoxicity complications include new or worsening left ventricular ejection fraction (LVEF), QT interval prolongation, myocardial ischaemia, hypertension, thromboembolic disease, cardiac device malfunction and valve disease. Baseline electrocardiogram (ECG) and transthoracic echocardiogram (TTE) are routinely performed for all patients commenced on cardiotoxic treatment, while other imaging modalities and biochemical markers have proven useful for monitoring. Management mainly includes early risk stratification and prompt identification of cardiovascular complications, with patient-specific surveillance throughout treatment. A multidisciplinary approach is crucial in determining the relationship between potential treatment benefits and cardiotoxicity, and whether the continuation of treatment is appropriate on a case-by-case basis. Early risk stratification, optimizing the patient's cardiovascular status prior to treatment, and prompt identification of suspected cardiotoxicity are key in significantly reducing risk. This article provides a comprehensive review of the various types of treatment-related cardiotoxicity, offering guidance on identifying high-risk patients, recognizing early signs of cardiotoxicity, and outlining appropriate treatment approaches and follow-up care for such cases.

3.
Anticancer Res ; 43(9): 3871-3880, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37648307

RESUMO

Gestational renal cell carcinoma (RCC) is an uncommon occurrence and presents a diagnostic and clinical challenge for healthcare providers. The manifestation of gestational RCC often lacks overt symptoms and can mimic physiological changes and disorders associated with pregnancy. Frequently, patients are asymptomatic, and the condition is detected during routine antenatal ultrasonography. However, the options for imaging modalities and treatment are limited due to the potential risks of harm to the developing fetus and interruption of pregnancy. Throughout the management of pregnant patients with RCC, both maternal and neonatal risks must be carefully considered, while respecting the patient's autonomy. Currently, there are no internationally or nationally recognized evidence-based guidelines for managing gestational RCC, highlighting the need for a multidisciplinary approach to treatment. Advances in surgical techniques have resulted in a shift from open surgeries to laparoscopic radical or partial nephrectomy procedures, with robotic-assisted approaches also gaining popularity. In cases of metastatic gestational RCC, termination of the pregnancy may be considered, and the appropriate treatment of RCC should be the priority. This article aims to provide a comprehensive review of the epidemiology, aetiology, clinical presentation, diagnosis, prognosis, and management of gestational RCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Laparoscopia , Gravidez , Recém-Nascido , Humanos , Feminino , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/terapia , Neoplasias Renais/diagnóstico , Neoplasias Renais/terapia , Família , Feto
4.
Pathogens ; 12(2)2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36839570

RESUMO

Cervical cancer is the fourth most common malignancy in females worldwide, and a leading cause of death in the United Kingdom (UK). The human papillomavirus (HPV) is the strongest risk factor for developing cervical intraepithelial neoplasia and cancer. Across the UK, the national HPV immunisation programme, introduced in 2008, has been successful in protecting against HPV-related infections. Furthermore, the National Health Service (NHS) implemented the cytology-based cervical cancer screening service to all females aged 25 to 64, which has observed a decline in cervical cancer incidence. In the UK, there has been an overall decline in age-appropriate coverage since April 2010. In 2019, the COVID-19 pandemic disrupted NHS cancer screening and immunisation programmes, leading to a 6.8% decreased uptake of cervical cancer screening from the previous year. Engagement with screening has also been associated with social deprivation. In England, incidence rates of cervical cancer were reported to be 65% higher in the most deprived areas compared to the least, with lifestyle factors such as cigarette consumption contributing to 21% of cervical cancer cases. In this article, we provide an update on the epidemiology of cervical cancer, and HPV pathogenesis and transmission, along with the current prevention programmes within the NHS.

5.
Cancers (Basel) ; 14(22)2022 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-36428661

RESUMO

Shear wave elastography (SWE) has shown promise in distinguishing lymph node malignancies. However, the diagnostic accuracies of various SWE parameters that quantify tissue stiffness are yet to be demonstrated. To evaluate the pooled diagnostic accuracy of different SWE parameters for differentiating lymph node malignancies, we conducted a systematic screening of four databases using the PRISMA guidelines. Lymph node biopsy was adopted as the reference standard. Emax (maximum stiffness), Emean (mean stiffness), Emin (minimum stiffness), and Esd (standard deviation) SWE parameters were subjected to separate meta-analyses. A sub-group analysis comparing the use of Emax in cervical (including thyroid) and axillary lymph node malignancies was also conducted. Sixteen studies were included in this meta-analysis. Emax and Esd demonstrated the highest pooled sensitivity (0.78 (95% CI: 0.69-0.87); 0.78 (95% CI: 0.68-0.87)), while Emean demonstrated the highest pooled specificity (0.93 (95% CI: 0.88-0.98)). From the sub-group analysis, the diagnostic performance did not differ significantly in cervical and axillary LN malignancies. In conclusion, SWE is a promising adjunct imaging technique to conventional ultrasonography in the diagnosis of lymph node malignancy. SWE parameters of Emax and Esd have been identified as better choices of parameters for screening clinical purposes.

6.
Comput Math Methods Med ; 2016: 4384508, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27274764

RESUMO

The patient-specific pre- and postsurgery cerebral arterial geometries in the study were reconstructed from computed tomography angiography (CTA). Three-dimensional computational fluid dynamics models were used to investigate the hemodynamic phenomena in the cerebral arteries before and after surgery of the aneurysm under realistic conditions. CFD simulations for laminar flow of incompressible Newtonian fluid were conducted by using commercial software, ANSYS v15, with the rigid vascular wall assumption. The study found that the flow patterns with the complex vortical structures inside the aneurysm were similar. We also found that the inflow jet streams were coming strongly in aneurysm sac in the presurgery models, while the flow patterns in postsurgery models were quite different from those in presurgery models. The average wall shear stress after surgery for model 1 was approximately three times greater than that before surgery, while it was about twenty times greater for model 2. The area of low WSS in the daughter saccular aneurysm region in model 2 is associated with aneurysm rupture. Thus the distribution of WSS in aneurysm region provides useful prediction for the risk of aneurysm rupture.


Assuntos
Ruptura Aórtica/fisiopatologia , Hemodinâmica , Aneurisma Intracraniano/fisiopatologia , Algoritmos , Ruptura Aórtica/diagnóstico , Vasos Sanguíneos/patologia , Simulação por Computador , Elasticidade , Humanos , Hidrodinâmica , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Aneurisma Intracraniano/diagnóstico , Modelos Teóricos , Complicações Pós-Operatórias
7.
Sensors (Basel) ; 15(10): 24903-13, 2015 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-26404279

RESUMO

We have investigated the effects of metal decoration on the gas-sensing properties of a device with two-dimensional (2D) molybdenum disulfide (MoS2) flake channels and graphene electrodes. The 2D hybrid-structure device sensitively detected NO2 gas molecules (>1.2 ppm) as well as NH3 (>10 ppm). Metal nanoparticles (NPs) could tune the electronic properties of the 2D graphene/MoS2 device, increasing sensitivity to a specific gas molecule. For instance, palladium NPs accumulate hole carriers of graphene/MoS2, electronically sensitizing NH3 gas molecules. Contrarily, aluminum NPs deplete hole carriers, enhancing NO2 sensitivity. The synergistic combination of metal NPs and 2D hybrid layers could be also applied to a flexible gas sensor. There was no serious degradation in the sensing performance of metal-decorated MoS2 flexible devices before/after 5000 bending cycles. Thus, highly sensitive and endurable gas sensor could be achieved through the metal-decorated 2D hybrid-structure, offering a useful route to wearable electronic sensing platforms.

8.
Obstet Gynecol Sci ; 57(1): 82-5, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24596824

RESUMO

Radical trachelectomy is a promising fertility-sparing treatment for patients with early stage cervical cancer who want to preserve their fertility. However, isthmic stenosis occurs frequently in patients who received radical trachelectomy and it is one of the causes of infertility following radical trachelectomy. Moreover, despite the treatment for recanalization of isthmic stenosis, recanalization can fail or isthmic stenosis can recur. Herein we report a successful pregnancy and birth by direct intraperitoneal insemination in an infertile woman with failure of recanalization of isthmic stenosis after laparoscopic radical trachelectomy.

9.
Int J Oral Sci ; 5(1): 7-13, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23579467

RESUMO

The periodontal ligament-derived mesenchymal stem cell is regarded as a source of adult stem cells due to its multipotency. However, the proof of chondrogenic potential of the cells is scarce. Therefore, we investigated the chondrogenic differentiation capacity of periodontal ligament derived mesenchymal stem cells induced by transforming growth factor (TGF)-ß3 and bone morphogenetic protein (BMP)-6. After isolation of periodontal ligament stem cells (PDLSCs) from human periodontal ligament, the cells were cultured in Dulbecco's modified Eagle's medium (DMEM) with 20% fetal bovine serum (FBS). A mechanical force initiated chondrogenic differentiation of the cells. For chondrogenic differentiation, 10 µg·L⁻¹ TGF-ß3 or 100 µg∙L⁻¹ BMP-6 and the combination treating group for synergistic effect of the growth factors. We analyzed the PDLSCs by fluorescence-activated cell sorting and chondrogenesis were evaluated by glycosaminoglycans assay, histology, immunohistochemistry and genetic analysis. PDLSCs showed mesenchymal stem cell properties proved by FACS analysis. Glycosaminoglycans contents were increased 217% by TGF-ß3 and 220% by BMP-6. The synergetic effect of TGF-ß3 and BMP-6 were shown up to 281% compared to control. The combination treatment increased Sox9, aggrecan and collagen II expression compared with not only controls, but also TGF-ß3 or BMP-6 single treatment dramatically. The histological analysis also indicated the chondrogenic differentiation of PDLSCs in our conditions. The results of the present study demonstrate the potential of the dental stem cell as a valuable cell source for chondrogenesis, which may be applicable for regeneration of cartilage and bone fracture in the field of cell therapy.


Assuntos
Proteína Morfogenética Óssea 6/farmacologia , Condrogênese/fisiologia , Células-Tronco Mesenquimais/fisiologia , Dente Serotino/citologia , Ligamento Periodontal/citologia , Dente Impactado/patologia , Fator de Crescimento Transformador beta3/farmacologia , Células-Tronco Adultas/fisiologia , Agrecanas/análise , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Separação Celular , Condrogênese/efeitos dos fármacos , Colágeno Tipo II/análise , Citometria de Fluxo , Glicosaminoglicanos/análise , Humanos , Imuno-Histoquímica , Células-Tronco Mesenquimais/efeitos dos fármacos , Ligamento Periodontal/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOX9/análise , Estresse Mecânico
10.
Korean Circ J ; 42(3): 154-63, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22493610

RESUMO

BACKGROUND AND OBJECTIVES: Glutaraldehyde (GA) has been used as a representative method of tissue preservation in cardiovascular surgery. However, GA has showed limited durability including calcification, mechanical failure and toxicity. To overcome those unsolved problems, we analyzed the crosslinking differences of primary amines, GA and genipin in their mechanical and biochemical properties with a single or double crosslinking agent for clinical application. MATERIALS AND METHODS: Samples were divided into 3 groups; control, single crosslinking fixation and double crosslinking fixation after decellurarization using bovine pericardium. For analysis of the biochemical and mechanical properties of each crosslinking method, tensile strength, percentage strain, thermal stability, resistance to pronase, nynhydrin and cytotoxicity test were studied. RESULTS: Combined hexamethylene diamine and suberic acid in the carbodiimide hydrochloride/N-hydroxysucinimide solution (EDC/NHS) after decellurarization, tensile strength and strain percentage were not statistically significant compared to the single crosslinking treated groups (p>0.05). Tissue crosslinking stability was weak in single treatment of diphenylphosphoryl azide, suberic acid, low concentration of EDC, hexamethylene diamine and procyanidin groups, but thermal stability and resistance to the pronase and ninhydrin were markedly increased in concentrated EDC/NHS or after combined double treatment with low concentration of GA or genipin (p<0.001). CONCLUSION: Single or double crosslinking with low concentration of carbodiimide, diphenylphosphonyl azide, procyanidin, suberic acid and hexane diamine were not as effective in mechanical, biochemical, cytotoxic and crosslinking properties compared to GA or genipin fixation, but their mechanical and chemical properties were much improved when combined with low concentrations of GA or genipin in the double crosslinking process.

11.
Korean J Thorac Cardiovasc Surg ; 45(6): 380-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23275920

RESUMO

BACKGROUND: Bovine pericardium is one of the most widely used materials in bioprosthetic heart valves. Immunologic responses have been implicated as potential causes of limited durability of xenogenic valves. This study aimed to determine the effectiveness of decellularization and α-galactosidase (α-gal) to remove major xenoreactive antigens from xenogenic tissues. MATERIALS AND METHODS: Recombinant Bacteroides thetaiotaomicron (B. thetaiotaomicron) α-gal or decellularization, or both were used to remove α-gal from bovine pericardium. It was confirmed by α-gal-bovine serum albumin-based enzyme-linked immunosorbent assay (ELISA), high-performance anion exchange chromatography, flow cytometry, 3,3'-diaminobenzidine-staining, and lectin-based ELISA. The mechanical properties of bovine pericardium after decellularization or α-gal treatment were investigated by tests of tensile-strength, permeability, and compliance. Collagen fiber rearrangement was also evaluated by a 20,000× transmission electron microscope (TEM). RESULTS: Recombinant B. thetaiotaomicron α-gal could effectively remove α-gal from bovine pericardium B. thetaiotaomicron (0.1 U/mL, pH 7.2) while recombinant human α-gal removed it recombinant human α-gal (10 U/mL, pH 5.0). There was no difference in the mechanical properties of fresh and recombinant α-gal-treated bovine pericardium. Furthermore, the TEM findings demonstrated that recombinant α-gal made no difference in the arrangement of collagen fiber bundles with decellularization. CONCLUSION: Recombinant B. thetaiotaomicron α-gal effectively removed α-gal from bovine pericardium with a small amount under physiological conditions compared to human recombinant α-gal, which may alleviate the harmful xenoreactive immunologic responses of α-gal. Recombinant α-gal treatment had no adverse effects on the mechanical properties of bovine pericardium.

12.
Int J Oncol ; 40(1): 277-86, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21887464

RESUMO

Proteins involved in the G1 phase of the cell cycle are aberrantly expressed, sometimes in mutated forms, in human cancers including human hepatocellular carcinoma. Upon attack by a DNA-damaging anticancer drug, a cell arrests at the G1 phase; this is a safety feature prohibiting entry of DNA-damaged cells into S-phase. p21WAF1/CIP1 prevents damaged cells from progressing to the next cell cycle. Here, we show that, in response to mitomycin C and doxorubicin, human hepatocellular carcinoma cells generate conflicting signals, mediated by cyclin E and p21WAF1/CIP1, which respectively accelerates and represses cell cycle transition. Exposure to these anticancer drugs led to rapid accumulation of cyclin E in both p53-proficient HepG2 and p53-deficient Hep3B cells. Such anticancer drug-induced cyclin E accumulation influenced the G1-S-phase transition, but not DNA fragmentation-mediated death. In p53-proficient HepG2 cells, accumulation of cyclin E was followed by an increase in the level of p53-dependent p21WAF1/CIP1, thereby inhibiting further the G1-S-phase transition. Sublethal drug concentrations also induced rapid accumulation of cyclin E, but p21WAF1/CIP1 accumulation was delayed, further facilitating the G1-S-phase transition. Eventually, most cells arrested in G2/M. Thus, mitomycin C- or doxorubicin-induced conflicting signals, mediated by cyclin E and p21WAF1/CIP1, are in play in human hepatocellular carcinoma cells. Damaged G1 cells either immediately enter S-phase, or do not do so at all, depending on the extent of DNA damage.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Ciclina E/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Fase G1/efeitos dos fármacos , Células Hep G2 , Humanos , Mitomicina/administração & dosagem , Fase S/efeitos dos fármacos , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/metabolismo
13.
Phys Chem Chem Phys ; 12(27): 7648-53, 2010 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-20523949

RESUMO

Aromatic pi-pi interaction in the presence of a metal atom has been investigated experimentally and theoretically with the model system of bis(eta(6)-benzene)chromium-benzene cluster (Cr(Bz)(2)-Bz) in which a free solvating benzene is non-covalently attached to the benzene moiety of Cr(Bz)(2). One-photon mass-analyzed threshold ionization (MATI) spectroscopy and first principles calculations are employed to identify the structure of Cr(Bz)(2)-Bz which adopts the parallel-displaced configuration. The decrease in ionization potential for Cr(Bz)(2)-Bz compared with Cr(Bz)(2), resulting from the increase of the cation-pi stabilization energy upon ionization, is consistent with the parallel-displaced structure of the cluster. Theoretical calculations give the detailed cluster structures with associated energetics, thus revealing the nature of pi-pi-metal or pi-pi-cation interactions at the molecular level.


Assuntos
Benzeno/química , Cromo/química , Metais/química , Compostos Organometálicos/química , Algoritmos , Cátions/química , Modelos Químicos , Solventes/química , Análise Espectral
14.
J Dermatolog Treat ; 21(4): 224-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20509814

RESUMO

BACKGROUND: Melasma is a common acquired pigmentary disorder which is sometimes hard to treat with conventional methods. Various kinds of modalities have been applied for the treatment of melasma but none shows constantly good results. OBJECTIVES: In this study, we would like to know the effect of low-dose 1064-nm Q-switched Nd:YAG laser (QSNYL) on melasma and want to evaluate the changes of skin after laser treatment. METHODS: Twenty melasma patients were enrolled. Two regions were evaluated from each patient; a total of 40 sites. The 1064-nm QSNYL at fluences of 2.0-3.5 J/cm(2) was used to treat the whole face, including the melasma lesions. The fluence was adjusted individually and increased until erythema was developed on the laser-treated area. The treatment was performed five times with a 1-week interval. Non-invasive measuring methods, including a chromatometer, mexameter, cutometer, visioscan and a corneometer, were used before and after treatment. RESULTS: The L-value from the chromatometer, which reflects the lightness of skin, was increased (0.86 +/- 1.67, p < 0.05). The melanin index from the mexameter was significantly decreased (-28.23 +/- 28.21, p < 0.001). The SEw value from the visioscan, which reflects the degree of wrinkling, decreased (-5.80 +/- 0.59, p = 0.040). None of the other measurement parameters showed significant changes. CONCLUSIONS: Low-dose 1064-nm QSNYL appears to be an effective treatment modality for melasma.


Assuntos
Dermatoses Faciais/radioterapia , Lasers de Estado Sólido/uso terapêutico , Terapia com Luz de Baixa Intensidade/métodos , Melanose/radioterapia , Adulto , Estudos de Coortes , Estética , Dermatoses Faciais/diagnóstico , Feminino , Seguimentos , Humanos , Lasers , Masculino , Melanose/diagnóstico , Pessoa de Meia-Idade , Probabilidade , Resultado do Tratamento , Adulto Jovem
15.
J Phys Chem A ; 112(31): 7125-7, 2008 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-18620373

RESUMO

Ar clustering dynamics around the metal-benzene sandwich complex, bis(eta (6)-benzene)chromium: Cr(Bz) 2, is found to occur in two distinct regimes. The shift of the ionization potential (IP) upon the addition of Ar is measured to be 151 cm (-1), and it is constant until the number of Ar solvents ( n) becomes 6. The IP shift per Ar is found to be suddenly decreased to 82 cm (-1) for the clusters of n = 7-12. The cluster distribution indicates that the n = 6 cluster is most populated in the molecular beam. These experimental findings with the aid of ab initio calculation indicate that the first six Ar solvent molecules are attached to top and bottom of Cr(Bz) 2 to give the robust structure for the Cr(Bz) 2-Ar 6 cluster whereas the next six Ar molecules are gathered on the side of the solute core to give the highly symmetric structure of the Cr(Bz) 2-Ar 12 cluster.

16.
J Chem Phys ; 126(3): 034308, 2007 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-17249872

RESUMO

The ionization behavior of the high Rydberg states of bis(eta(6)-benzene)chromium in the presence of ac and/or dc fields has been explored. The application of an ac scrambling field at the time of laser excitation lengthens the lifetime of the Rydberg state by almost two orders of magnitude. The lifetime enhancement by the scrambling field is much more effective for n<100 than it is for n>100 Rydberg states. The pulsed-field ionization of Rydberg states of n<100 shows the typical diabatic ionization behavior for low n. The two distinct ionization behaviors observed for the relatively low (n=50-100) and high (n=100-200) Rydberg states suggest that the former originate from the optically accessed nf Rydberg series, whereas the latter are due to np Rydberg series. Based on the understanding of the ionization behavior of bis(eta(6)-benzene)chromium, the accurate ionization potential is deduced to give IP=5.4665+/-0.0003 eV. Optimization of the various electric field conditions greatly enhances the spectral sensitivity of the mass-analyzed threshold ionization (MATI) spectroscopy. The high-resolution MATI spectrum of the title molecule obtained here provides precise cationic vibrational frequencies for many skeletal and benzene ring modes. A number of vibrational modes are newly identified, and the ambiguity regarding to some mode assignments is now clearly resolved through the Frank-Condon analysis based on ab initio calculations.

17.
J Phys Chem A ; 110(49): 13183-7, 2006 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-17149831

RESUMO

Adiabatic ionization energies of dimethyl sulfide (DMS) and ethylene sulfide (thiirane) are both accurately and precisely determined to be 8.6903 +/- 0.0009 and 9.0600 +/- 0.0009 eV, respectively, by vacuum-UV mass-analyzed threshold ionization (MATI) spectroscopy. Also reported are vibrational frequencies of DMS and thiirane monocations. Simulations using a Franck-Condon analysis based on ab initio molecular structures reproduce the experimental findings quite well. Detailed vibrational structures are discussed with the aid of ab initio calculations. Ionization-induced structural changes provide the information about the role of the sulfur nonbonding orbital in the geometrical layout of the title compounds.

18.
Yonsei Med J ; 47(4): 583-6, 2006 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-16941752

RESUMO

Abdominal actinomycosis causing hydronephrosis in a patient with a ventriculoperitoneal shunt is very rare. A 27- year-old female patient was admitted complaining of lower abdominal pain. She had undergone ventriculoperitoneal shunt surgery 10 years ago. Abdominal Ultrasonography and a CT scan demonstrated an inflammatory mass in the lower left quadrant of the abdomen causing obstructive hydroureter and hydronephrosis. Laparotomy revealed a diffusely infiltrating mass involving the small bowel, mesentery, and sigmoid colon, and a 1cm perforation in the sigmoid colon. Actinomycosis was diagnosed upon histological examination. After treatment with antibiotics and surgery, the patient's condition improved.


Assuntos
Actinomicose/diagnóstico , Colo Sigmoide/lesões , Colo Sigmoide/patologia , Perfuração Intestinal/diagnóstico , Dor Abdominal , Adulto , Feminino , Humanos , Inflamação , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Ultrassonografia , Derivação Ventriculoperitoneal
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