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1.
Magn Reson Chem ; 61(7): 407-417, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36967631

RESUMO

The Savannah River Site stores approximately 36 million gallons of radioactive and hazardous waste that contains approximately 245 million curies. The waste is sent through various chemical processes to reduce its volume and to separate various components. The facility plans to replace formic acid (a chemical used to reduce soluble mercury) with glycolic acid. Recycle solution with glycolate may flow back to the tank farm, where the glycolate can generate hydrogen gas by thermal and radiolytic mechanisms. The current analytical method for detecting glycolate (ion chromatography) in supernatant requires a large dilution to reduce interference from the nitrate anions. Hydrogen nuclear magnetic resonance is an analytical method that requires less sample dilution. It takes advantage of the CH2 group in glycolate. Liquid samples were spiked with four different levels of glycolate to build a calibration line, as it is recommended in the standard addition method. The detection and quantitation limits determined were 1 and 5 ppm, respectively, for 32 scans, which is well below the process limit of 10 ppm. In one test, 800 scans of a supernatant spiked with 1 ppm glycolate resulted in a -CH2 peak with a signal-to-noise ratio of 36.

2.
Artigo em Inglês | MEDLINE | ID: mdl-36215878

RESUMO

Cyclic Nucleotides are important in regulating platelet function. Increases in 3'5'-cyclic adenosine monophosphate (cAMP) and 3'5'-cyclic guanosine monophosphate (cGMP) inhibit platelet aggregation and are pharmacological targets for antiplatelet therapy. Here we report an improved method for determining cAMP and cGMP concentrations and, for the first time, in washed platelet supernatants by combining high-performance liquid chromatography and tandem mass spectrometry (LC-MS/MS). Characteristic peaks of the substrates, cGMP or cAMP and their internal standards were identified in negative-ion electrospray ionisation using multiple reaction monitoring. Compared with previously reported methods, the method presented here shows high precision with the lowest lower limit of quantification (LLoQ) to date (10 pg/mL). The effect of a novel catecholamine, 6-nitrodopamine, on cyclic nucleotide levels was quantified. Our results showed that this new method was fast, sensitive, and highly reproducible.


Assuntos
AMP Cíclico , GMP Cíclico , Cromatografia Líquida/métodos , GMP Cíclico/análise , GMP Cíclico/química , AMP Cíclico/análise , Espectrometria de Massas em Tandem/métodos , Agregação Plaquetária , Plaquetas/química
3.
Ann Surg Oncol ; 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35378634

RESUMO

BACKGROUND: The Neoadjuvant Breast Symphony Trial (NBRST) demonstrated the 70-gene risk of distant recurrence signature, MammaPrint, and the 80-gene molecular subtyping signature, BluePrint, precisely determined preoperative pathological complete response (pCR) in breast cancer patients. We report 5-year follow-up results in addition to an exploratory analysis by age and menopausal status. METHODS: The observational, prospective NBRST (NCT01479101) included 954 early-stage breast cancer patients aged 18-90 years who received neoadjuvant chemotherapy and had clinical and genomic data available. Chemosensitivity and 5-year distant metastasis-free survival (DMFS) and overall survival (OS) were assessed. In a post hoc subanalysis, results were stratified by age (≤ 50 vs. > 50 years) and menopausal status in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) tumors. RESULTS: MammaPrint and BluePrint further classified 23% of tumors to a different subtype compared with immunohistochemistry, with more precise correspondence to pCR rates. Five-year DMFS and OS were highest in MammaPrint Low Risk, Luminal A-type and HER2-type tumors, and lowest in MammaPrint High Risk, Luminal B-type and Basal-type tumors. There was no significant difference in chemosensitivity between younger and older patients with Low-Risk (2.2% vs. 3.8%; p = 0.64) or High-Risk tumors (14.5% vs. 11.5%; p = 0.42), or within each BluePrint subtype; this was similar when stratifying by menopausal status. The 5-year outcomes were comparable by age or menopausal status for each molecular subtype. CONCLUSION: Intrinsic preoperative chemosensitivity and long-term outcomes were precisely determined by BluePrint and MammaPrint regardless of patient age, supporting the utility of these assays to inform treatment and surgical decisions in early-stage breast cancer.

4.
Life Sci ; 276: 119425, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33781827

RESUMO

AIMS: Human umbilical cord vessels (HUCV) release dopamine and nitric oxide (NO). This study aims to verify whether HUCV release nitrocatecholamines such as 6-nitrodopamine (6-ND). MAIN METHODS: Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was used to identify 6-ND release from HUCV rings incubated in Krebs-Henseileit's solution. Vascular reactivity of HUCV rings was tested (with and without endothelium integrity) by suspension of the rings in an organ bath under isometric tension and application of 6-ND and other known mediators. KEY FINDINGS: LC-MS/MS revealed a basal release of 6-ND from endothelium intact from both human umbilical artery (HUA) and vein (HUV). The endothelium intact release was inhibited by the pre-treatment with NO synthesis inhibitor L-NAME (100 µM). In contrast to dopamine, noradrenaline and adrenaline, 6-ND did not contract HUCV, even in presence of L-NAME or ODQ. 6-ND (10 µM) produced a rightward shift of the concentration-response curves to dopamine (pA2: 5.96 in HUA and 5.72 in HUV). Contractions induced by noradrenaline and adrenaline were not affected by pre-incubation with 6-ND (10 µM). In U-46619 (10 nM) pre-contracted endothelium intact tissues, 6-ND and the dopamine D2-receptor antagonist haloperidol induced concentration-dependent relaxations of HUA and HUV. Incubation with the dopamine D1-receptor antagonist SCH-23390 (10 nM) abolished relaxation induced by fenoldopam but did not affect those induced by 6-ND. SIGNIFICANCE: 6-ND is released by HUCV and acts as a selective dopamine D2-receptor antagonist in this tissue. This represents a novel mechanism by which NO may modulate vascular reactivity independently of cGMP production.


Assuntos
Dopamina/análogos & derivados , Endotélio Vascular/fisiologia , Artérias Umbilicais/fisiologia , Veias Umbilicais/fisiologia , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Adolescente , Adulto , Células Cultivadas , Dopamina/farmacologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Feminino , Humanos , Artérias Umbilicais/efeitos dos fármacos , Artérias Umbilicais/metabolismo , Veias Umbilicais/efeitos dos fármacos , Veias Umbilicais/metabolismo , Adulto Jovem
5.
Ann Surg Oncol ; 24(9): 2539-2546, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28447218

RESUMO

BACKGROUND: Pertuzumab became a standard part of neoadjuvant therapy for human epidermal growth factor receptor 2-positive (HER2+) breast cancers approximately halfway through Neoadjuvant Breast Registry Symphony Trial (NBRST) enrollment, providing a unique opportunity to determine biologically which clinical HER2+ patients benefit most from dual targeting. As a neoadjuvant phase 4 study, NBRST classifies patients by both conventional and molecular subtyping. METHODS: Of 308 clinical HER2+ patients enrolled in NBRST between 2011 and 2014 from 62 U.S. institutions, 297 received neoadjuvant chemotherapy (NCT) with HER2-targeted therapy and underwent surgery. This study compared the pathologic complete response (pCR) rate of BluePrint versus clinical subtypes with treatment, specifically differences between trastuzumab (T) treatment and trastuzumab and pertuzumab (T/P) treatment. RESULTS: In this study, 60% of the patients received NCT-T, and 40% received NCT-T/P. The overall pCR rate (ypT0/isN0) was 47%. BluePrint classified 161 tumors (54%) as HER2 type, with a pCR rate of 65%. This was significantly higher than the pCR rate for the 91 HER2+ tumors (31%) classified as luminal (18%) (p = 0.00001) and the 45 tumors (15%) classified as basal (44%) (p = 0.0166). The patients treated with T/P had higher pCR rates than those treated with trastuzumab alone. The difference was most pronounced in the BluePrint luminal patients (8 vs. 31%). The highest pCR was reached by the BluePrint HER2-type patients treated with T/P (76%). CONCLUSIONS: The addition of pertuzumab leads to increased pCR rates for all HER2+ patient groups except for the BluePrint basal-type patients. This better response was most pronounced for the BluePrint luminal-type patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Receptor ErbB-2/metabolismo , Trastuzumab/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Neoplasias da Mama/metabolismo , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Feminino , Testes Genéticos , Genômica , Humanos , Terapia Neoadjuvante , Estudos Prospectivos , Trastuzumab/administração & dosagem , Resultado do Tratamento
6.
Ann Surg Oncol ; 24(3): 669-675, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27770345

RESUMO

PURPOSE: Hormone receptor-positive (HR+) tumors have heterogeneous biology and present a challenge for determining optimal treatment. In the Neoadjuvant Breast Registry Symphony Trial (NBRST) patients were classified according to MammaPrint/BluePrint subtyping to provide insight into the response to neoadjuvant endocrine therapy (NET) or neoadjuvant chemotherapy (NCT). OBJECTIVE: The purpose of this predefined substudy was to compare MammaPrint/BluePrint with conventional 'clinical' immunohistochemistry/fluorescence in situ hybridization (IHC/FISH) subtyping in 'clinical luminal' [HR+/human epidermal growth factor receptor 2-negative (HER2-)] breast cancer patients to predict treatment sensitivity. METHODS: NBRST IHC/FISH HR+/HER2- breast cancer patients (n = 474) were classified into four molecular subgroups by MammaPrint/BluePrint subtyping: Luminal A, Luminal B, HER2, and Basal type. Pathological complete response (pCR) rates were compared with conventional IHC/FISH subtype. RESULTS: The overall pCR rate for 'clinical luminal' patients to NCT was 11 %; however, 87 of these 474 patients were reclassified as Basal type by BluePrint, with a high pCR rate of 32 %. The MammaPrint index was highly associated with the likelihood of pCR (p < 0.001). Fifty-three patients with BluePrint Luminal tumors received NET with an aromatase inhibitor and 36 (68 %) had a clinical response. CONCLUSIONS: With BluePrint subtyping, 18 % of clinical 'luminal' patients are classified in a different subgroup, compared with conventional assessment, and these patients have a significantly higher response rate to NCT compared with BluePrint Luminal patients. MammaPrint/BluePrint subtyping can help allocate effective treatment to appropriate patients. In addition, accurate identification of subtype biology is important in the interpretation of neoadjuvant treatment response since lack of pCR in luminal patients does not portend the worse prognosis associated with residual disease in Basal and HER2 subtypes.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/classificação , Neoplasias da Mama/tratamento farmacológico , Perfilação da Expressão Gênica , Tipagem Molecular/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastrozol , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Hidrocarbonetos Aromáticos com Pontes/administração & dosagem , Quimioterapia Adjuvante , Tomada de Decisão Clínica , Ciclofosfamida/administração & dosagem , Docetaxel , Doxorrubicina/administração & dosagem , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Letrozol , Mastectomia Segmentar , Pessoa de Meia-Idade , Terapia Neoadjuvante , Nitrilas/administração & dosagem , Estudos Prospectivos , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Sistema de Registros , Tamoxifeno/administração & dosagem , Taxoides/administração & dosagem , Resultado do Tratamento , Triazóis/administração & dosagem , Adulto Jovem
7.
Ann Surg Oncol ; 23(5): 1522-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26714960

RESUMO

BACKGROUND: The prospective Neoadjuvant Breast Symphony Trial (NBRST) study found that MammaPrint/BluePrint functional molecular subtype is superior to conventional immunohistochemistry/fluorescence in situ hybridization subtyping for predicting pathologic complete response (pCR) to neoadjuvant chemotherapy. The purpose of this substudy was to determine if the rate of pCR is affected by tumor size. METHODS: The NBRST study includes breast cancer patients who received neoadjuvant chemotherapy. MammaPrint/BluePrint subtyping classified patients into four molecular subgroups: Luminal A, Luminal B, HER2 (human epidermal growth factor receptor 2), and Basal type. Probability of pCR (ypT0/isN0) as a function of tumor size and molecular subgroup was evaluated. RESULTS: A total of 608 patients were evaluable with overall pCR rates of 28.5 %. Luminal A and B patients had significantly lower rates of pCR (6.1 and 8.7 %, respectively) than either basal (37.1 %) or HER2 (55.0 %) patients (p < 0.001). The probability of pCR significantly decreased with tumor size >5 cm [p = 0.022, odds ratio (OR) 0.58, 95 % confidence interval (CI) 0.36, 0.93]. This relationship was statistically significant in the Basal (p = 0.026, OR 0.46, 95 % CI 0.23, 0.91) and HER2 (p = 0.039, OR 0.36, 95 % CI 0.14, 0.95) subgroups. In multivariate logistic regression analyses, the dichotomized tumor size variable was not significant in any of the molecular subgroups. DISCUSSION: Even though tumor size would intuitively be a clinical determinant of pCR, the current analysis showed that the adjusted OR for tumor size was not statistically significant in any of the molecular subgroups. Factors significantly associated with pCR were PR status, grade, lymph node status, and BluePrint molecular subtyping, which had the strongest correlation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/patologia , Terapia Neoadjuvante , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Indução de Remissão , Taxa de Sobrevida , Carga Tumoral , Adulto Jovem
8.
Ann Surg Oncol ; 21(10): 3261-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25099655

RESUMO

PURPOSE: The purpose of the NBRST study is to compare a multigene classifier to conventional immunohistochemistry (IHC)/fluorescence in situ hybridization (FISH) subtyping to predict chemosensitivity as defined by pathological complete response (pCR) or endocrine sensitivity as defined by partial response. METHODS: The study includes women with histologically proven breast cancer, who will receive neoadjuvant chemotherapy (NCT) or neoadjuvant endocrine therapy. BluePrint in combination with MammaPrint classifies patients into four molecular subgroups: Luminal A, Luminal B, HER2, and Basal. RESULTS: A total of 426 patients had definitive surgery. Thirty-seven of 211 (18 %) IHC/FISH hormone receptor (HR)+/HER2- patients were reclassified by Blueprint as Basal (n = 35) or HER2 (n = 2). Fifty-three of 123 (43 %) IHC/FISH HER2+ patients were reclassified as Luminal (n = 36) or Basal (n = 17). Four of 92 (4 %) IHC/FISH triple-negative (TN) patients were reclassified as Luminal (n = 2) or HER2 (n = 2). NCT pCR rates were 2 % in Luminal A and 7 % Luminal B patients versus 10 % pCR in IHC/FISH HR+/HER2- patients. The NCT pCR rate was 53 % in BluePrint HER2 patients. This is significantly superior (p = 0.047) to the pCR rate in IHC/FISH HER2+ patients (38 %). The pCR rate of 36 of 75 IHC/FISH HER2+/HR+ patients reclassified as BPLuminal is 3 %. NCT pCR for BluePrint Basal patients was 49 of 140 (35 %), comparable to the 34 of 92 pCR rate (37 %) in IHC/FISH TN patients. CONCLUSIONS: BluePrint molecular subtyping reclassifies 22 % (94/426) of tumors, reassigning more responsive patients to the HER2 and Basal categories while reassigning less responsive patients to the Luminal category. These findings suggest that compared with IHC/FISH, BluePrint more accurately identifies patients likely to respond (or not respond) to NCT.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Terapia Neoadjuvante , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Sistema de Registros , Taxa de Sobrevida , Adulto Jovem
9.
Phys Rev Lett ; 102(14): 147203, 2009 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-19392478

RESUMO

We show that the zero-temperature phase diagram of the vortex free sector of the Kitaev model is in one-to-one correspondence with that of the classical dimer model on the same lattice. We find that the model generically has three distinct phases. On a honeycomb lattice with a 3 x 3 fundamental domain all three phases are accessible. As the couplings are varied, there are two distinct transitions. The new transition is one to a gapped phase that opens up in the interior of the B phase.

10.
Scand J Infect Dis ; 39(3): 257-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17366058

RESUMO

Pustular dermatitis caused by Salmonella stanley developed on the arm of a veterinary surgeon after the delivery of a dead bovine calf. The vet did not develop any systemic symptoms and made a full recovery. This is the only report of cutaneous infection caused by this organism.


Assuntos
Infecções por Salmonella/patologia , Salmonella/isolamento & purificação , Dermatopatias Bacterianas/patologia , Animais , Bovinos , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Infecções por Salmonella/etiologia , Infecções por Salmonella/microbiologia , Salmonelose Animal/microbiologia , Dermatopatias Bacterianas/etiologia , Dermatopatias Bacterianas/microbiologia , Zoonoses/microbiologia
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