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1.
Am J Cardiol ; 210: 85-92, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37852567

RESUMO

We describe 2 challenging cases of cardiac transthyretin amyloidosis initially treated as cardiac amyloidosis light chain in the setting of active myeloma. Endomyocardial biopsy with mass spectrometry was essential to confirm the appropriate diagnosis to direct the treatment.


Assuntos
Neuropatias Amiloides Familiares , Cardiomiopatias , Mieloma Múltiplo , Humanos , Mieloma Múltiplo/complicações , Mieloma Múltiplo/diagnóstico , Cardiomiopatias/diagnóstico , Pré-Albumina , Neuropatias Amiloides Familiares/complicações , Neuropatias Amiloides Familiares/diagnóstico , Coração
2.
Am J Cardiol ; 207: 271-279, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37769570

RESUMO

Recurrence of cardiac sarcoidosis (CS) and giant cell myocarditis (GCM) after heart transplant is rare, with rates of 5% in CS and 8% in GCM. We aim to identify all reported cases of recurrence in the literature and to assess clinical course, treatments, and outcomes to improve understanding of the conditions. A systematic review, utilizing Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines, was conducted by searching MEDLINE/PubMed and Embase of all available literature describing post-transplant recurrent granulomatous myocarditis, CS, or GCM. Data on demographics, transplant, recurrence, management, and outcomes data were collected from each publication. Comparison between the 2 groups were made using standard statistical approaches. Post-transplant GM recurrence was identified in 39 patients in 33 total publications. Reported cases included 24 GCM, 12 CS, and 3 suspected cases. Case reports were the most frequent form of publication. Mean age of patients experiencing recurrence was 42 years for GCM and 48 years for CS and favored males (62%). Time to recurrence ranged from 2 weeks to 9 years post-transplant, occurring earlier in GCM (mean 1.8 vs 3.0 years). Endomyocardial biopsies (89%) were the most utilized diagnostic method over cardiac magnetic resonance and positron emission tomography. Recurrence treatment regimens involved only steroids in 40% of CS, whereas other immunomodulatory regimens were utilized in 70% of GCM. In conclusion, GCM and CS recurrence after cardiac transplantation holds associated risks including concurrent acute cellular rejection, a higher therapeutic demand for GCM recurrence compared with CS, and mortality. New noninvasive screening techniques may help modify post-transplant monitoring regimens to increase both early detection and treatment of recurrence.


Assuntos
Cardiomiopatias , Transplante de Coração , Miocardite , Sarcoidose , Adulto , Humanos , Masculino , Biópsia , Cardiomiopatias/diagnóstico , Cardiomiopatias/etiologia , Cardiomiopatias/patologia , Células Gigantes/patologia , Transplante de Coração/efeitos adversos , Miocardite/diagnóstico , Miocardite/etiologia , Miocardite/terapia , Sarcoidose/diagnóstico , Sarcoidose/patologia
3.
BMJ Case Rep ; 16(4)2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37185314

RESUMO

Riedel's thyroiditis (RT) is a rare inflammatory autoimmune disease, often associated with various forms of systemic fibrosis such as sclerosing mesenteritis (SM). A woman in her late 30s presented with a diffusely enlarged firm goiter and a mesenteric mass complicated by biliary obstruction and hydronephrosis. Labs and thyroid ultrasound were consistent with autoimmune thyroiditis. Abdominal imaging demonstrated a mesenteric mass that encased mesenteric vessels and ureter. Flow cytometry and infectious workup were negative. Both thyroid and mesenteric biopsies revealed dense fibrosis with patchy lymphoplasmacytic aggregates, no evidence of carcinoma, lymphoma, or IgG4-related disease, which confirmed diagnoses of RT and SM. She improved clinically with steroids. The coincidental timing of thyroid enlargement and the mesenteric mass, and the similarity in histology suggest an association between RT and SM. Overall, the case highlights the challenges in diagnosing RT given its rarity and emphasises the importance of early treatment to prevent systemic involvement.


Assuntos
Bócio , Tireoidite , Feminino , Humanos , Tireoidite/complicações , Tireoidite/diagnóstico , Tireoidite/patologia , Bócio/complicações , Fibrose
4.
Mod Pathol ; 36(9): 100221, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37236510

RESUMO

Transbronchial cryobiopsy (TBCB) is increasingly used for the diagnosis of fibrosing interstitial pneumonias, but there are few detailed descriptions of the pathologic findings in such cases. It has been proposed that a combination of patchy fibrosis and fibroblast foci with an absence of alternative features is diagnostic of usual interstitial pneumonia (UIP; ie, idiopathic pulmonary fibrosis [IPF]) in TBCB. In this study, we reviewed 121 TBCB in which a diagnosis of fibrotic hypersensitivity pneumonitis (FHP; n = 83) or IPF (n = 38) was made by multidisciplinary discussion and evaluated a range of pathologic features. Patchy fibrosis was found in 65 of 83 (78%) biopsies from FHP and 32of 38 (84%) biopsies from UIP/IPF cases. Fibroblast foci were present in 47 of 83 (57%) FHP and 27 of 38 (71%) UIP/IPF cases. Fibroblast foci/patchy fibrosis combined did not favor either diagnosis. Architectural distortion was seen in 54 of 83 (65%) FHP and 32 of 38 (84%) UIP/IPF cases (odds ratio [OR] for FHP, 0.35; P = .036) and honeycombing in 18 of 83 (22%) and 17 of 38 (45%), respectively (OR, 0.37; P = .014). Airspace giant cells/granulomas were present in 13 of 83 (20%) FHP and 1 of 38 (2.6%) UIP/IPF cases (OR for FHP, 6.87; P = .068), and interstitial giant cells/granulomas in 20 of 83 (24%) FHP and 0 of 38 (0%) UIP/IPF (OR, 6.7 x 106; P = .000). We conclude that patchy fibrosis plus fibroblast foci can be found in TBCB from both FHP and UIP/IPF. The complete absence of architectural distortion/honeycombing favors a diagnosis of FHP, as does the presence of airspace or interstitial giant cells/granulomas, but these measures are insensitive, and many cases of FHP cannot be separated from UIP/IPF on TBCB.


Assuntos
Alveolite Alérgica Extrínseca , Fibrose Pulmonar Idiopática , Doenças Pulmonares Intersticiais , Humanos , Fibrose Pulmonar Idiopática/diagnóstico , Fibrose Pulmonar Idiopática/patologia , Doenças Pulmonares Intersticiais/patologia , Fibrose , Biópsia , Alveolite Alérgica Extrínseca/diagnóstico , Alveolite Alérgica Extrínseca/patologia , Granuloma/patologia , Pulmão/patologia
5.
Head Neck Pathol ; 16(3): 918-927, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35157212

RESUMO

Sinonasal leiomyosarcoma (LMS) is a rare and aggressive mesenchymal tumor with smooth muscle differentiation. The sinonasal tract is an unusual primary site for LMS, as scant smooth muscle exists in this location, with only 75 cases reported in the English literature including the case presented herein. Sinonasal LMS is considered an aggressive head and neck tumor with significant potential for recurrence and metastasis. Since recurrence is high and the potential for late metastasis exists, lifelong follow-up in these patients would be beneficial, especially among those with previous history of RB.


Assuntos
Leiomiossarcoma , Neoplasias dos Seios Paranasais , Seios Paranasais , Humanos , Cavidade Nasal
6.
J Pathol Transl Med ; 55(4): 265-270, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34225446

RESUMO

Palmar fibromatosis (Dupuytren disease/contracture) is the most common type of fibromatosis, defined as a benign proliferation of fibroblasts and myofibroblasts. The disease process is most common in white, middle-aged and older men occurring at the distal palmar crease leading to nodules and contracture, which in many cases recur after surgical treatment. In a similar process, plantar fibromatosis (Ledderhose disease) is a proliferation of fibroblasts and myofibroblasts on the plantar aponeurosis of mostly middle-aged patients that may lead to painful nodules but usually does not lead to contracture. Both processes are histologically similar, composed of a bland cellular proliferation of spindle cells with a bluish appearance and with a variable amount of background collagen, depending on the age of the lesion. The etiology of both lesions is still uncertain, while treatment ranges from observation to surgery, with some pharmacologic agents being investigated with mixed success. In this paper we provide an overview of both processes with regards to clinical and radiologic findings, pathophysiology, diagnosis, treatment, and prognosis.

7.
Cardiovasc Pathol ; 52: 107317, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33434636

RESUMO

Primary tumors of the heart are uncommon; even rarer are primary cardiac neuroendocrine tumors. To our knowledge, only two cases have been described to date, both being high-grade tumors. We report a solitary low-grade neuroendocrine tumor of the heart, unexpectedly discovered during aortic valve repair for infectious bacterial endocarditis on the wall of the right ventricle in a 44-year-old man with a history of balloon valvulotomy as a child. Frozen section was sent intraoperatively and demonstrated a plasmacytoid neoplasm. Final pathology of the biopsies showed a tumor composed of both cohesive and discohesive plasmacytoid cells separated by a vascular network and strands of fibrosis. The tumor showed strong reactivity for AE1/3, synaptophysin, and CDX2 with focal reactivity for chromogranin-A and CD56. Neither necrosis nor a mitotic rate of greater than 2 mitoses per 2 mm2 was seen. A colonoscopy was performed and demonstrated only a tubular adenoma. An esophagogastroduodenoscopy was unremarkable. PET-CT DOTATATE, performed after complete resection of the tumor, demonstrated no abnormal radiotracer uptake. The patient continues to do well at present, 1 year later, and reports no symptoms attributable to carcinoid syndrome or disease progression. The patient was assigned by medical oncology to yearly follow-up and imaging, and is considered to have no evidence of disease.


Assuntos
Neoplasias Cardíacas , Tumores Neuroendócrinos , Adulto , Neoplasias Cardíacas/diagnóstico por imagem , Neoplasias Cardíacas/patologia , Humanos , Masculino , Gradação de Tumores , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons , Cintilografia
8.
Semin Diagn Pathol ; 37(4): 199-210, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32534865

RESUMO

This review focuses on the diagnosis of select benign processes, ranging from reactive entities to heterotopic tissues to neoplasms, which may occur in the mediastinum. Currently, the mediastinum can be evaluated and biopsied with endoscopic procedures. Therefore, cytopathology specimens, fine needle aspirations, and small biopsies play an important role in the diagnosis of these lesions. In this review, an emphasis is given to relevant clinical presentations, histologic and cytologic findings, differential diagnoses, ancillary testing, and interpretation. Pitfalls are reviewed and discussed in each section. It is important for both surgical pathologists and cytopathologists to be familiar with these entities and their cytologic and histologic features that may be helpful in reaching a diagnosis.


Assuntos
Neoplasias do Mediastino/diagnóstico , Neoplasias do Mediastino/patologia , Mediastino/patologia , Diagnóstico Diferencial , Humanos
9.
Environ Sci Technol ; 54(7): 4275-4285, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32142602

RESUMO

Waters coproduced with hydrocarbons from unconventional oil and gas reservoirs such as the hydraulically fractured Middle Devonian Marcellus Shale in the Appalachian Basin, USA, contain high levels of total dissolved solids (TDS), including Ba, which has been variously ascribed to drilling mud dissolution, interaction with pore fluids or shale exchangeable sites, or fluid migration through fractures. Here, we show that Marcellus Shale produced waters contain some of the heaviest Ba (high 138Ba/134Ba) measured to date (δ138Ba = +0.36‰ to +1.49‰ ± 0.06‰) and are distinct from overlying Upper Devonian/Lower Mississippian reservoirs (δ138Ba = -0.83‰ to -0.52‰). Marcellus Shale produced water values do not overlap with drilling mud barite (δ138Ba ≈ 0.0‰) and are significantly offset from Ba reservoirs within the producing portion of the Marcellus Shale, including exchangeable sites and carbonate cement. Precipitation, desorption, and diffusion processes are insufficient or in the wrong direction to produce the observed enrichments in heavy Ba. We hypothesize that the produced water is derived primarily from brines adjacent to and most likely below the Marcellus Shale, although such deep brines have not yet been obtained for Ba isotope analysis. Barium isotopes show promise for tracking formation waters and for understanding water-rock interaction under downhole conditions.


Assuntos
Gás Natural , Poluentes Químicos da Água , Região dos Apalaches , Bário , Isótopos , Campos de Petróleo e Gás , Águas Residuárias
10.
Int J Surg Pathol ; 28(1): 102-108, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31382829

RESUMO

SMARCA4-deficient thoracic sarcoma (SMARCA4-DTS) is a recently described entity with a poor prognosis that is defined by certain genetic alterations in the BAF chromatin remodeling complex, specifically SMARCA4 and SMARCA2. We present a case of a SMARCA4-DTS in a 59 year-old male with a heavy smoking history who was found to have an unexpected right upper lobe lung mass on routine chest radiograph after a visit to his primary care physician. This led to a biopsy with a diagnosis of poorly differentiated carcinoma at an outside institution. The patient was subsequently seen at our facility for surgical intervention. The right upper lobectomy contained a 7.2-cm poorly differentiated malignancy with slightly discohesive cells arranged in sheets and nests, abundant geographic necrosis, and with many areas showing rhabdoid morphology. The tumor was focally reactive for CK7, AE1/3, Cam5.2, and SALL4 and showed scattered reactivity for CD34 and SOX2. There was complete loss of reactivity for both SMARCA4 and SMARCA2. The histology and immunophenotype were all consistent with the diagnosis of a SMARCA4-DTS. Next-generation sequencing showed a frameshift mutation in the SMARCA4 gene and no abnormality with the SMARCA2 gene. Interestingly, this tumor was confined to the pulmonary parenchyma with no invasion of the visceral pleura nor the mediastinum and with no clinically apparent metastases at the time of presentation. This case is presented to add to the cohort of cases described to date and to discuss the immunohistochemical and molecular findings with regard to SMARCA2.


Assuntos
Biomarcadores Tumorais/deficiência , DNA Helicases/deficiência , Neoplasias Pulmonares/diagnóstico , Proteínas Nucleares/deficiência , Sarcoma/diagnóstico , Fatores de Transcrição/deficiência , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Sarcoma/metabolismo , Sarcoma/patologia
11.
J Vasc Surg Cases Innov Tech ; 5(3): 310-313, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31334407

RESUMO

A 63-year-old man presented with left lower extremity ischemia and pain. Left lower extremity angiography revealed calcification throughout the superficial femoral artery, prompting atherectomy and angioplasty with a drug-coated balloon. About 1 week after the procedure, he developed angulated ulcers with central eschar on the left lower extremity and was referred to the dermatology clinic. A biopsy showed cutaneous intravascular foreign material consistent with hydrophilic polymer gel. In patients who develop retiform purpura and ulcerations after endovascular procedures, the diagnosis of hydrophilic polymer embolus should be considered. Treatment consists of supportive care, making early identification vital to avoid unnecessary amputation.

12.
Lab Med ; 46(3): 259-64, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26199269

RESUMO

OBJECTIVES: To implement Lean principles to accommodate expanding volumes of gastrointestinal biopsies and to improve laboratory processes overall. DESIGN: Our continuous improvement (kaizen) project analyzed the current state for gastrointestinal biopsy handling using value-stream mapping for specimens obtained at a 487-bed tertiary care pediatric hospital in Dallas, Texas. We identified non-value-added time within the workflow process, from receipt of the specimen in the histology laboratory to the delivery of slides and paperwork to the pathologist. To eliminate non-value-added steps, we implemented the changes depicted in a revised-state value-stream map. RESULTS: Current-state value-stream mapping identified a total specimen processing time of 507 minutes, of which 358 minutes were non-value-added. This translated to a process cycle efficiency of 29%. Implementation of a revised-state value stream resulted in a total process time reduction to 238 minutes, of which 89 minutes were non-value-added, and an improved process cycle efficiency of 63%. CONCLUSIONS: Lean production principles of continuous improvement and waste elimination can be successfully implemented within the clinical laboratory.


Assuntos
Biópsia/métodos , Eficiência Organizacional , Gastroenteropatias/diagnóstico , Patologia Clínica , Criança , Hospitais Pediátricos , Humanos , Fluxo de Trabalho
13.
Head Neck Pathol ; 8(4): 454-62, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25409851

RESUMO

Over the past decade, there have been remarkable advances in bone tumor pathology. Insights into the genetic basis and pathobiology of many tumor types have impacted diagnosis, classification, and treatment. However, because gnathic lesions may comprise only a small proportion of cases overall for many tumors, clinicopathologic features and management considerations specific to this subset may be overlooked. Here we provide a summary of recent developments in the following tumor types: osteosarcoma (OS), chondrosarcoma (CS), osteoid osteoma (OO), osteoblastoma (OB), and Ewing sarcoma (ES). In particular, we will give special consideration to cases arising in the jaws.


Assuntos
Condrossarcoma/patologia , Neoplasias Maxilomandibulares/patologia , Osteoblastoma/patologia , Osteoma Osteoide/patologia , Osteossarcoma/patologia , Sarcoma de Ewing/patologia , Neoplasias Ósseas/patologia , Cartilagem/patologia , Humanos
14.
J Chromatogr A ; 1338: 92-101, 2014 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-24636755

RESUMO

Granulocyte colony-stimulating factor (G-CSF) is a hematopoietic growth factor regulating granulopoiesis. The recombinant human granulocyte colony-stimulating factor (rhG-CSF) is widely used for the treatment of granulopenia in humans. Filgrastim is a rhG-CSF analogue and is marketed under various brand names, including Neupogen(®) (Amgen), Imumax(®) (Abbott Laboratories), Neukine(®) (Intas Biopharmaceuticals) and others. It is banned in both human and equine sports owing to its potential for misuse. In order to control the abuse of filgrastim in equine sports, a method to identify unequivocally its prior use in horses is required. This study describes an effective screening method for filgrastim in equine plasma by enzyme-linked immunosorbant assays (ELISA), and a follow-up confirmatory method for the unequivocal identification of filgrastim by analysing its highly specific tryptic peptide (1)MTPLGPASSLPQSFLLK(17). Filgrastim was isolated from equine plasma by immunoaffinity purification. After trypsin digestion, the mixture was analysed by nano-liquid chromatography-tandem mass spectrometry (LC/MS/MS). Filgrastim could be detected and confirmed at 0.2ng/mL in equine plasma. The applicability of the ELISA screening method and the LC/MS/MS confirmation method was demonstrated by analysing post-administration plasma samples collected from horses having been co-administered with epoetin alfa as recombinant human erythropoietin (rhEPO) and filgrastim as rhG-CSF. rhEPO and filgrastim could be detected in plasma samples collected from horses for at least 57 and 101h respectively. To our knowledge, this is the first identification of filgrastim in post-administration samples from horses.


Assuntos
Eritropoetina/sangue , Fator Estimulador de Colônias de Granulócitos/sangue , Cavalos , Sequência de Aminoácidos , Animais , Cromatografia Líquida/métodos , Dopagem Esportivo/prevenção & controle , Eritropoetina/química , Eritropoetina/farmacologia , Filgrastim , Fator Estimulador de Colônias de Granulócitos/química , Humanos , Dados de Sequência Molecular , Proteínas Recombinantes/sangue , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Espectrometria de Massas em Tandem/métodos
15.
PLoS One ; 8(9): e73193, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24066038

RESUMO

PURPOSE: Iron deposition has been shown to occur following myocardial infarction (MI). We investigated whether such focal iron deposition within chronic MI lead to electrical anomalies. METHODS: Two groups of dogs (ex-vivo (n = 12) and in-vivo (n = 10)) were studied at 16 weeks post MI. Hearts of animals from ex-vivo group were explanted and sectioned into infarcted and non-infarcted segments. Impedance spectroscopy was used to derive electrical permittivity ([Formula: see text]) and conductivity ([Formula: see text]). Mass spectrometry was used to classify and characterize tissue sections with (IRON+) and without (IRON-) iron. Animals from in-vivo group underwent cardiac magnetic resonance imaging (CMR) for estimation of scar volume (late-gadolinium enhancement, LGE) and iron deposition (T2*) relative to left-ventricular volume. 24-hour electrocardiogram recordings were obtained and used to examine Heart Rate (HR), QT interval (QT), QT corrected for HR (QTc) and QTc dispersion (QTcd). In a fraction of these animals (n = 5), ultra-high resolution electroanatomical mapping (EAM) was performed, co-registered with LGE and T2* CMR and were used to characterize the spatial locations of isolated late potentials (ILPs). RESULTS: Compared to IRON- sections, IRON+ sections had higher[Formula: see text], but no difference in[Formula: see text]. A linear relationship was found between iron content and [Formula: see text] (p<0.001), but not [Formula: see text] (p = 0.34). Among two groups of animals (Iron (<1.5%) and Iron (>1.5%)) with similar scar volumes (7.28% ± 1.02% (Iron (<1.5%)) vs 8.35% ± 2.98% (Iron (>1.5%)), p = 0.51) but markedly different iron volumes (1.12% ± 0.64% (Iron (<1.5%)) vs 2.47% ± 0.64% (Iron (>1.5%)), p = 0.02), QT and QTc were elevated and QTcd was decreased in the group with the higher iron volume during the day, night and 24-hour period (p<0.05). EAMs co-registered with CMR images showed a greater tendency for ILPs to emerge from scar regions with iron versus without iron. CONCLUSION: The electrical behavior of infarcted hearts with iron appears to be different from those without iron. Iron within infarcted zones may evolve as an arrhythmogenic substrate in the post MI period.


Assuntos
Ferro/metabolismo , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/fisiopatologia , Animais , Cães , Capacitância Elétrica , Eletrocardiografia , Sistema de Condução Cardíaco , Imageamento por Ressonância Magnética
16.
Cardiovasc Pathol ; 22(5): 351-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23628153

RESUMO

Primary vascular neoplasms are rare entities. They were first described as arising spontaneously in the aorta and other vessels. However, in the past several decades, a number of systemic artery-derived vascular neoplasms, mostly sarcomas, have been reported as arising in intimate association with synthetic grafts. We describe two additional cases of intimal sarcoma seen at our institution. The first is an invasive intimal sarcoma detected in a thoracoabdominal aortic aneurysm at the time of surgical intervention. The second is a superficial spreading intimal sarcoma associated with a Dacron-coated graft, in place for 9 years, detected when the graft was replaced. When the patient died 3 months later, a metastatic subcutaneous sarcomatous lesion was detected at autopsy. In these cases, we studied selective molecular pathways that may be involved in the transformation of benign endothelium to malignant endothelium, with implications for possible therapeutic targets. These cases are presented in order to contribute additional data to the literature involving these vascular neoplasms and to potentially provide a spectrum of disease seen in the vasculature tissues that may arise spontaneously or after placement of a synthetic graft.


Assuntos
Aorta/metabolismo , Aorta/patologia , Sarcoma/metabolismo , Sarcoma/patologia , Neoplasias Vasculares/metabolismo , Neoplasias Vasculares/patologia , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Torácica/patologia , Aneurisma da Aorta Torácica/cirurgia , Prótese Vascular/efeitos adversos , Carcinogênese , Humanos , Imuno-Histoquímica , Masculino , Redes e Vias Metabólicas , Sarcoma/etiologia , Túnica Íntima/metabolismo , Túnica Íntima/patologia , Neoplasias Vasculares/etiologia
17.
Environ Sci Technol ; 46(6): 3545-53, 2012 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-22360406

RESUMO

Extraction of natural gas by hydraulic fracturing of the Middle Devonian Marcellus Shale, a major gas-bearing unit in the Appalachian Basin, results in significant quantities of produced water containing high total dissolved solids (TDS). We carried out a strontium (Sr) isotope investigation to determine the utility of Sr isotopes in identifying and quantifying the interaction of Marcellus Formation produced waters with other waters in the Appalachian Basin in the event of an accidental release, and to provide information about the source of the dissolved solids. Strontium isotopic ratios of Marcellus produced waters collected over a geographic range of ~375 km from southwestern to northeastern Pennsylvania define a relatively narrow set of values (ε(Sr)(SW) = +13.8 to +41.6, where ε(Sr) (SW) is the deviation of the (87)Sr/(86)Sr ratio from that of seawater in parts per 10(4)); this isotopic range falls above that of Middle Devonian seawater, and is distinct from most western Pennsylvania acid mine drainage and Upper Devonian Venango Group oil and gas brines. The uniformity of the isotope ratios suggests a basin-wide source of dissolved solids with a component that is more radiogenic than seawater. Mixing models indicate that Sr isotope ratios can be used to sensitively differentiate between Marcellus Formation produced water and other potential sources of TDS into ground or surface waters.


Assuntos
Monitoramento Ambiental/métodos , Indústrias Extrativas e de Processamento , Gás Natural , Isótopos de Estrôncio/análise , Minas de Carvão , Resíduos Industriais , Pennsylvania , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análise
18.
Biomed Chromatogr ; 24(7): 744-51, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19882746

RESUMO

This paper describes the application of gas chromatography-mass spectrometry (GC-MS) for in vitro and in vivo studies of 6-OXO in horses, with a special aim to identify the most appropriate target metabolite to be monitored for controlling the administration of 6-OXO in racehorses. In vitro studies of 6-OXO were performed using horse liver microsomes. The major biotransformation observed was reduction of one keto group at the C3 or C6 positions. Three in vitro metabolites, namely 6alpha-hydroxyandrost-4-ene-3,17-dione (M1), 3alpha-hydroxyandrost-4-ene-6,17-dione (M2a) and 3beta-hydroxyandrost-4-ene-6,17-dione (M2b) were identified. For the in vivo studies, two thoroughbred geldings were each administered orally with 500 mg of androst-4-ene-3,6,17-trione (5 capsules of 6-OXO((R))) by stomach tubing. The results revealed that 6-OXO was extensively metabolized. The three in vitro metabolites (M1, M2a and M2b) identified earlier were all detected in post-administration urine samples. In addition, seven other urinary metabolites, derived from a further reduction of either one of the remaining keto groups or one of the remaining keto groups and the olefin group, were identified. These metabolites included 6alpha,17beta-dihydroxyandrost-4-en-3-one (M3a), 6,17-dihydroxyandrost-4-en-3-one (M3b and M3c), 3beta,6beta-dihydroxyandrost-4-en-17-one (M4a), 3,6-dihydroxyandrost-4-en-17-one (M4b), 3,6-dihydroxyandrostan-17-one (M5) and 3,17-dihydroxyandrostan-6-one (M6). The longest detection time observed in urine was up to 46 h for the M6 metabolite. For blood samples, the peak 6-OXO plasma concentration was observed 1 h post administration. Plasma 6-OXO decreased rapidly and was not detectable 12 h post administration.


Assuntos
Anabolizantes/análise , Anabolizantes/urina , Androstenos/análise , Androstenos/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cavalos/urina , Anabolizantes/metabolismo , Androstenos/metabolismo , Animais , Dopagem Esportivo , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo
19.
Anal Chim Acta ; 649(2): 222-9, 2009 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-19699398

RESUMO

The quantification of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (Mutagen X or MX) in drinking water is difficult due to the low concentration of MX in drinking water, its high sensitivity to pH change, and matrix effects that interfere with the derivatization and analysis. Typically, the quantification of MX involves derivatization by methylation. We present a one-step derivatization procedure for MX using N-methyl-bis-trifluoroacetamide (MBTFA) and analysis by ion trap GC/MS/MS. The new method resulted in a significant reduction in analysis time, and improved detection limits. The abundant and selective ions in the mass spectrum of the trifluoroacylated MX (trifluoroacetic acid-4-chloro-3-dichloromethyl-5-oxo-2-hydro-furan-2-yl ester) allowed for a clear identification and quantification of the compound, with a method detection limit of 7.7 ng L(-1), and a limit of quantitation of 24.4 ng L(-1). The trifluoroacylated MX was shown to be stable for 30 days in an excess of the derivatization reagent. The new method was applied for the determination of MX in several drinking water samples, with a concentration range from not-detected to 517 ng L(-1); these values are comparable to those obtained in previous studies. The development of this new simplified analytical method for MX is an important step forward in the field of disinfection by-product (DBP) research, particularly in light of the recent scientific recognition of halogenated furanones as emerging drinking water contaminants. Increased analytical ability may well be a decisive factor in the monitoring of these disinfection by-products.


Assuntos
Furanos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Mutagênicos/análise , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Cloro/química , Furanos/isolamento & purificação , Mutagênicos/isolamento & purificação , Extração em Fase Sólida , Poluentes Químicos da Água/isolamento & purificação
20.
Can Assoc Radiol J ; 59(1): 22-9, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18386754

RESUMO

OBJECTIVE: To determine the percentage of interventional radiologists who currently perform 3 interventional procedures: carotid stenting, vertebroplasty, and endovascular aneurysm repair (EVAR) in Canada, and impediments to their future performance by other interventional radiologists. METHODS: An anonymous online survey was emailed to all members of the Canadian Interventional Radiology Association (CIRA). The survey was open for a period of 2 months. RESULTS: A total of 75 survey responses were received (of an estimated 247). Carotid stenting, vertebroplasty, and EVAR were performed at 40%, 59%, and 46% of respondents' centres respectively. Wait times, from referral to consultation, and from consultation to procedure, were both typically between 2 to 4 weeks, longer for EVAR. Of respondents currently not performing these procedures, 26%, 28%, and 16% anticipated beginning to perform carotid stenting, vertebroplasty, and EVAR, respectively, in the proceeding year from time of survey. Of respondents who wished to perform the procedure, the greatest impediments were a lack of training, lack of a referral base, and lack of support from their radiology department and (or) colleagues. CONCLUSIONS: Although carotid stenting, vertebroplasty, and EVAR were being performed at about one-half of respondent's centres, and there will likely be greater adoption of the procedures in the near future, there remain substantial impediments. The greatest impediments to additional radiologists performing these procedures were a lack of training, lack of referral base, and lack of support from their radiology department and (or) colleagues. The former impediment suggested an unmet need for additional training courses.


Assuntos
Aneurisma/cirurgia , Estenose das Carótidas/cirurgia , Radiologia Intervencionista/estatística & dados numéricos , Stents/estatística & dados numéricos , Procedimentos Cirúrgicos Vasculares/estatística & dados numéricos , Vertebroplastia , Angioplastia , Atitude do Pessoal de Saúde , Canadá , Coleta de Dados , Previsões , Humanos , Padrões de Prática Médica , Serviço Hospitalar de Radiologia , Radiologia Intervencionista/educação , Encaminhamento e Consulta , Inquéritos e Questionários , Fatores de Tempo , Vertebroplastia/estatística & dados numéricos , Listas de Espera
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