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Oliveira GR, Machry RV, Cadore-Rodrigues AC, Sarkis-Onofre R, Valandro LF, Bacchi A, Pereira G, Spazzin AO. Fatigue Properties of Weakened and Non-weakened Roots Restored with CAD-CAM Milled Fiber Post, Prefabricated Fiber Post, or Cast Metal Post. Oper Dent 2022; 47:658-669. [PMID: 36251571 DOI: 10.2341/21-032-l] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/27/2021] [Indexed: 11/23/2022]
Abstract
STATEMENT OF PROBLEM Customized glass fiber posts using CAD-CAM technology have been suggested for restoring endodontically treated teeth. However, how weakened or non-weakened roots restored with anatomical CAD-CAM posts behave under cyclic fatigue is not clear. OBJECTIVE To evaluate the load-bearing capacity under fatigue (fatigue failure load [FFL], the number of cycles for failure [CFF], and survival probabilities) and fracture pattern of weakened and non-weakened roots restored with CAD-CAM fiber post and cores, metal cast-post-core, and prefabricated fiber post and resin core. METHODS AND MATERIALS A total of 60 crack-free bovine incisor roots (13 mm in length) with standard geometry were obtained and randomly allocated considering the factor "root condition" in two levels (weakened and non-weakened). Thus, half of the roots were weakened to obtain a wall thickness of 0.5 mm. After that, the endodontic treatment was executed, all roots embedded with acrylic resin and the specimens randomly allocated (n=10) considering the factor "post system" in three levels (CAD-CAM: CAD-CAM milled glass-fiber post and core; MBC: metallic-based post and core; and FRC: prefabricated glass-fiber post and composite resin core). The posts were luted with a dual-cure self-adhesive luting agent. Then, all teeth received a metallic crown. An initial load of 100 N at 20 Hz for 5000 cycles was applied for the step-stress fatigue test, followed by incremental steps of 50 N for 20,000 cycles each step, up to failure. A fracture pattern analysis was performed. RESULTS CAD-CAM fiber post (FFL: 865 N; CFF: 311,000 cycles) presented similar fatigue performance (p>0.05) to FRC (FFL: 925 N; CFF: 335,000 cycles), with 100% of repairable fractures for non-weakened roots; however, both groups presented worse performance than MBC (p<0.05; FFL: 1265 N; CFF: 471,000 cycles) which led to 100% of catastrophic failures. No statistical difference was found in fatigue performance among the three systems for weakened roots (p>0.05; FFL: 1035-1170 N; CFF: 379,000-433,000 cycles), with a high rate of catastrophic failures. CONCLUSIONS CAD-CAM fiber post presented similar fatigue performance to MBC and FRC approaches when restoring weakened roots. CAD-CAM was similar to FRC when restoring non-weakened roots, while MBC enhanced fatigue properties in this scenario.
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Affiliation(s)
- G R Oliveira
- Gabriel Rodrigues Oliveira, DDS, Graduate Program in Dentistry, Atitus Education, Passo Fundo, Rio Grande do Sul, Brazil
| | - R V Machry
- Renan Vaz Machry, PhD, Post-Graduate Program in Oral Science, Prosthodontics Unit, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul, Brazil
| | - A C Cadore-Rodrigues
- Ana Carolina Cadore-Rodrigues, PhD, Post-Graduate Program in Oral Science, Prosthodontics Unit, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul, Brazil
| | - R Sarkis-Onofre
- Rafael Sarkis-Onofre, PhD, Graduate Program in Dentistry, Atitus Education, Passo Fundo, Rio Grande do Sul, Brazil
| | - L F Valandro
- Luiz Felipe Valandro, PhD, Post-Graduate Program in Oral Science, Prosthodontics Unit, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul, Brazil
| | - A Bacchi
- Ataís Bacchi, PhD, Post-Graduate Program in Dentistry, Paulo Picanço School of Dentistry, Fortaleza, Brazil
| | - Gkr Pereira
- *Gabriel Kalil Rocha Pereira, PhD, Post-Graduate Program in Oral Science, Prosthodontics Unit, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul, Brazil
| | - A O Spazzin
- Aloísio Oro Spazzin, PhD, Graduate Program in Dentistry, Atitus Education, Passo Fundo, Rio Grande do Sul, Brazil
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Patino M, Parakh A, Lo GC, Agrawal M, Kambadakone AR, Oliveira GR, Sahani DV. Virtual Monochromatic Dual-Energy Aortoiliac CT Angiography With Reduced Iodine Dose: A Prospective Randomized Study. AJR Am J Roentgenol 2019; 212:467-474. [DOI: 10.2214/ajr.18.19935] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Affiliation(s)
- Manuel Patino
- Department of Radiology, Division of Abdominal Imaging, Massachusetts General Hospital, Harvard Medical School, 55 Fruit St, Boston, MA 02114
| | - Anushri Parakh
- Department of Radiology, Division of Abdominal Imaging, Massachusetts General Hospital, Harvard Medical School, 55 Fruit St, Boston, MA 02114
| | - Grace C. Lo
- Department of Radiology, Division of Abdominal Imaging, Massachusetts General Hospital, Harvard Medical School, 55 Fruit St, Boston, MA 02114
| | - Mukta Agrawal
- Department of Radiology, Division of Abdominal Imaging, Massachusetts General Hospital, Harvard Medical School, 55 Fruit St, Boston, MA 02114
| | - Avinash R. Kambadakone
- Department of Radiology, Division of Abdominal Imaging, Massachusetts General Hospital, Harvard Medical School, 55 Fruit St, Boston, MA 02114
| | - George R. Oliveira
- Department of Radiology, Division of Abdominal Imaging, Massachusetts General Hospital, Harvard Medical School, 55 Fruit St, Boston, MA 02114
| | - Dushyant V. Sahani
- Department of Radiology, Division of Abdominal Imaging, Massachusetts General Hospital, Harvard Medical School, 55 Fruit St, Boston, MA 02114
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3
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Scholtz JE, Lu MT, Hedgire S, Meyersohn NM, Oliveira GR, Prabhakar AM, Gupta R, Kalra MK, Shepard JAO, Hoffmann U, Ghoshhajra BB. Incidental pulmonary nodules in emergent coronary CT angiography for suspected acute coronary syndrome: Impact of revised 2017 Fleischner Society Guidelines. J Cardiovasc Comput Tomogr 2017; 12:28-33. [PMID: 29195841 DOI: 10.1016/j.jcct.2017.11.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 10/05/2017] [Accepted: 11/12/2017] [Indexed: 12/17/2022]
Abstract
BACKGROUND Pulmonary nodules (PN) are frequently detected incidentally during coronary computed tomography angiography (CTA). We evaluated whether the 2017 Fleischner Society guidelines may result in a decrease of follow-up testing of incidental PN as compared to prior guidelines in patients undergoing coronary CTA. METHODS We conducted a retrospective study of a registry of emergency department patients who underwent coronary CTA for acute coronary syndrome assessment between 2012 and 2017. Based on guidelines, patients <35 years, history of cancer, or prior exams showing stability of PN were excluded. Patients >60 years, history of smoking, irregular/spiculated PN morphology, or PN size >20 mm were classified as high-risk for lung cancer. Radiological findings pertaining to PN were identified (PN size, morphology, quantity) through review of radiology reports. PN follow-up recommendations were established using 2017 Fleischner Society Guidelines and compared with prior guidelines for solid (2005) and subsolid (2013) PN. Data were analyzed with Student's t-test. RESULTS The registry included 2066 patients (female 45.1%, 52.9 ± 11.0 years), of which 578 (28.0%) reported PN. 438 of those (21.2%) were eligible for guideline-based follow-up evaluation. 205 (4 6.8%) were classified as high-risk for lung cancer. 2017 guidelines reduced the number of individuals requiring follow-up by 64.5%, from 264 (12.8%) to 94 patients (4.5%) when compared to prior guidelines (p < 0.001). The minimum number of follow-up chest CTs decreased by 55.8% from 430 to 190 (p < 0.001). CONCLUSION Application of the 2017 Fleischner Society Guidelines resulted in a significant decrease of follow-up testing for incidental PN in patients undergoing coronary CTA for suspected acute coronary syndrome.
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Affiliation(s)
- Jan-Erik Scholtz
- Cardiac MR PET CT Program, Department of Radiology (Cardiovascular Imaging) and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, 165 Cambridge Street, Suite 400, Boston, MA 02114-2750, USA; Department for Diagnostic and Interventional Radiology, University Hospital Frankfurt, Johann-Wolfgang-Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt/Main, Germany.
| | - Michael T Lu
- Cardiac MR PET CT Program, Department of Radiology (Cardiovascular Imaging) and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, 165 Cambridge Street, Suite 400, Boston, MA 02114-2750, USA
| | - Sandeep Hedgire
- Cardiac MR PET CT Program, Department of Radiology (Cardiovascular Imaging) and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, 165 Cambridge Street, Suite 400, Boston, MA 02114-2750, USA
| | - Nina M Meyersohn
- Cardiac MR PET CT Program, Department of Radiology (Cardiovascular Imaging) and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, 165 Cambridge Street, Suite 400, Boston, MA 02114-2750, USA
| | - George R Oliveira
- Department for Diagnostic and Interventional Radiology, University Hospital Frankfurt, Johann-Wolfgang-Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt/Main, Germany
| | - Anand M Prabhakar
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit St, Boston, MA 02114-2750, USA
| | - Rajiv Gupta
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit St, Boston, MA 02114-2750, USA
| | - Mannudeep K Kalra
- Department for Diagnostic and Interventional Radiology, University Hospital Frankfurt, Johann-Wolfgang-Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt/Main, Germany
| | - Jo-Anne O Shepard
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit St, Boston, MA 02114-2750, USA
| | - Udo Hoffmann
- Cardiac MR PET CT Program, Department of Radiology (Cardiovascular Imaging) and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, 165 Cambridge Street, Suite 400, Boston, MA 02114-2750, USA
| | - Brian B Ghoshhajra
- Cardiac MR PET CT Program, Department of Radiology (Cardiovascular Imaging) and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, 165 Cambridge Street, Suite 400, Boston, MA 02114-2750, USA
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Cowan AJ, Stevenson PA, Gooley TA, Frayo SL, Oliveira GR, Smith SD, Green DJ, Roden JE, Pagel JM, Wood BL, Press OW, Gopal AK. Results of a phase I-II study of fenretinide and rituximab for patients with indolent B-cell lymphoma and mantle cell lymphoma. Br J Haematol 2017; 176:583-590. [PMID: 28055107 DOI: 10.1111/bjh.14451] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 09/12/2016] [Indexed: 11/29/2022]
Abstract
Fenretinide, a synthetic retinoid, induces apoptotic cell death in B-cell non-Hodgkin lymphoma (B-NHL) and acts synergistically with rituximab in preclinical models. We report results from a phase I-II study of fenretinide with rituximab for B-NHLs. Eligible diagnoses included indolent B-NHL or mantle cell lymphoma. The phase I design de-escalated from fenretinide at 900 mg/m2 PO BID for days 1-5 of a 7-day cycle. The phase II portion added 375 mg/m2 IV rituximab weekly on weeks 5-9 then every 3 months. Fenretinide was continued until progression or intolerance. Thirty-two patients were treated: 7 in phase I, and 25 in phase II of the trial. No dose-limiting toxicities were observed. The phase II component utilized fenretinide 900 mg/m2 twice daily with rituximab. The most common treatment-related adverse events of grade 3 or higher were rash (n = 3) and neutropenia (n = 3). Responses were seen in 6 (24%) patients on the phase II study, with a median duration of response of 47 months (95% confidence interval, 2-56). The combination of fenretinide and rituximab was well tolerated, yielded a modest overall response rate, but with prolonged remission durations. Further study should focus on identifying the responsive subset of B-NHL.
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Affiliation(s)
- Andrew J Cowan
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.,Division of Medical Oncology, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Phillip A Stevenson
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Ted A Gooley
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Shani L Frayo
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - George R Oliveira
- Department of Radiology, Harvard Medical School, MGH Hospital, Boston, MA, USA
| | - Stephen D Smith
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.,Division of Medical Oncology, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Damian J Green
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.,Division of Medical Oncology, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Jennifer E Roden
- Division of Medical Oncology, Department of Medicine, University of Washington, Seattle, WA, USA
| | | | - Brent L Wood
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.,Division of Hematopathology, Department of Laboratory Medicine, University of Washington, Seattle, WA, USA
| | - Oliver W Press
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.,Division of Medical Oncology, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Ajay K Gopal
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.,Division of Medical Oncology, Department of Medicine, University of Washington, Seattle, WA, USA
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Lima CB, Migotto DL, Oliveira GR, Souza TC, Santana RO, Castejon FV, Tanure CBGS, Santana AP, Stringhini JH, Racanicci AMC. Dietary Supplementation of Barbatimão (Stryphnodendron Adstringens) and Pacari (Lafoensia Pacari) Extracts on the Oxidative Stability and Quality of Chicken Meat. Rev Bras Cienc Avic 2016. [DOI: 10.1590/1806-9061-2015-0212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- CB Lima
- University of Brasília, Brazil
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Abstract
Peripheral artery disease (PAD) has become increasingly common in the US patient population and can be a highly symptomatic and significant source of morbidity. When PAD is suspected, the first-line screening study that is obtained is typically a noninvasive evaluation that includes the ankle brachial index (ABI). Following a positive screening study, invasive catheter digital subtraction angiography (DSA) has been historically used to image the peripheral artery system and still remains the gold standard. However, newer developments in axial imaging including computed tomography angiography (CTA) and magnetic resonance angiography (MRA) have in large part supplanted DSA for imaging the peripheral artery system in clinical practice. Benefits of CTA include rapid noninvasive acquisition, wide availability, high spatial resolution, and the ability to generate isotropic datasets on 64-detector row and higher CT scanners, thereby allowing for multiplanar 3D reformatting. Drawbacks of CTA include the exposure to both iodinated contrast and ionizing radiation, although the radiation dose exposure is lower than for DSA, and newer techniques such as using low tube voltage and rapid acquisition times allow for lower contrast doses. The presence of vascular calcification also limits the evaluation of small distal arteries using CTA, although the development of dual-energy CT techniques has significantly addressed this issue. Benefits of MRA include the avoidance of exposure to ionizing radiation and high diagnostic accuracy, while drawbacks include limited availability and increased cost along with the risk of nephrogenic systemic fibrosis that is associated with gadolinium-based contrast agents, although the latter can be mitigated by using newer non-contrast MR angiography techniques. Future technical advances in CT and MR hardware and software and MR pulse sequences will likely lead to the broader applicability and increased accuracy of noninvasive axial imaging in the evaluation of patients with peripheral artery disease.
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Affiliation(s)
- Nandini M Meyersohn
- Division of Cardiovascular Imaging, Massachusetts General Hospital, Boston, MA, USA,
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7
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Lima CBD, Racanicci AMC, Oliveira GR, Migotto DL, Amador SA, Souza TCD, Tanure CBGS, Vieira A. Effects of the Dietary Supplementation of Sucupira (Pterodon Emarginatus Vog.) and Copaiba (Copaifera Langsdorffii) Resinoils on Chicken Breast and Thigh Meat Quality and Oxidative Stability. Rev Bras Cienc Avic 2015. [DOI: 10.1590/1516-635xspecialissuenutrition-poultryfeedingadditives047-056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
| | | | | | | | - SA Amador
- University of Brasília (UnB), Brazil
| | | | | | - A Vieira
- University of Brasília (UnB), Brazil
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Lucchetti G, Lucchetti ALG, Oliveira GR, Crispim D, Pires SL, Gorzoni ML, Panicio CRG, Koenig HG. Nursing home care: exploring the role of religiousness in the mental health, quality of life and stress of formal caregivers. J Psychiatr Ment Health Nurs 2014; 21:403-13. [PMID: 23701527 DOI: 10.1111/jpm.12092] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/28/2013] [Indexed: 11/27/2022]
Abstract
Despite the high number of studies on family caregivers, there is little research on the impact of religiosity on formal caregiving (paid providers). We examine the role of religiousness in the mental health, quality of life and stress of nurse aides (NA) who provide care for patients in a nursing home. NA in a Brazilian nursing home were invited to participate. Because of its coping function, we hypothesized that religiousness was related to better mental health and quality of life. Linear regression was used to test this hypothesis and control for confounders. Compared with the Brazilian general population, NA scored higher on measures of religious involvement. Intrinsic religiosity was associated with better mental health and quality of life. Organizational religiosity was associated with better social functioning, better general mental health and fewer anxiety symptoms. Non-organizational religiosity (prayer), however, was associated with negative outcomes, such as higher stress, poorer general health perceptions and more anxiety symptoms. Most NA indicated that they had prayed for and with their patients. In conclusion, paid caregivers (NA) have a strong sense of religiousness, which plays an important role in many ways, including the type of care they provide, their mental health and their quality of life.
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Affiliation(s)
- G Lucchetti
- Department of Medicine, Federal University of Juiz de Fora, Juiz de Fora; Department of Research, São Paulo Medical Spiritist Association, São Paulo, São Paulo; Department of Research, Hospital João Evangelista, São Paulo, São Paulo
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Affiliation(s)
- Roy G Bryan
- Department of Radiology, Massachusetts General Hospital, 55 Fruit St., Boston, MA 02215.
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10
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Butros SR, Liu R, Oliveira GR, Ganguli S, Kalva S. Venous compression syndromes: clinical features, imaging findings and management. Br J Radiol 2013; 86:20130284. [PMID: 23908347 DOI: 10.1259/bjr.20130284] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Extrinsic venous compression is caused by compression of the veins in tight anatomic spaces by adjacent structures, and is seen in a number of locations. Venous compression syndromes, including Paget-Schroetter syndrome, Nutcracker syndrome, May-Thurner syndrome and popliteal venous compression will be discussed. These syndromes are usually seen in young, otherwise healthy individuals, and can lead to significant overall morbidity. Aside from clinical findings and physical examination, diagnosis can be made with ultrasound, CT, or MR conventional venography. Symptoms and haemodynamic significance of the compression determine the ideal treatment method.
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Affiliation(s)
- S R Butros
- Department of Radiology, Division of Vascular Imaging and Interventional Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
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Abstract
A 27-year-old woman presented to her primary care doctor's office with left flank pain. CT of the abdomen showed an isolated left renal vein thrombus. The clot was initially attributed to her oral contraceptive use; however, closer inspection of CT images revealed nutcracker phenomenon (compression of the renal vein between the superior mesenteric artery and abdominal aorta). Intravascular ultrasound imaging confirmed the diagnosis. Nutcracker syndrome is a rare condition, which if left untreated may cause damage to the left kidney. Although under diagnosed, there are several treatment options available ranging from simple surveillance to surgical resolution.
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Affiliation(s)
- Syed Kashif Mahmood
- Department of Internal Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA.
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Budde LE, Zhang MM, Shustov AR, Pagel JM, Gooley TA, Oliveira GR, Chen TL, Knudsen NL, Roden JE, Kammerer BE, Frayo SL, Warr TA, Boyd TE, Press OW, Gopal AK. A phase I study of pulse high-dose vorinostat (V) plus rituximab (R), ifosphamide, carboplatin, and etoposide (ICE) in patients with relapsed lymphoma. Br J Haematol 2013; 161:183-91. [PMID: 23356514 DOI: 10.1111/bjh.12230] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 12/27/2012] [Indexed: 01/20/2023]
Abstract
Given the poor outcomes of relapsed aggressive lymphomas and preclinical data suggesting that ≥2·5 μmol/l concentrations of vorinostat synergize with both etoposide and platinums, we hypothesized that pulse high-dose vorinostat could safely augment the anti-tumour activity of (R)ICE [(rituximab), ifosphamide, carboplatin, etoposide] chemotherapy. We conducted a phase I dose escalation study using a schedule with oral vorinostat ranging from 400 mg/d to 700 mg bid for 5 d in combination with the standard (R)ICE regimen (days 3, 4 and 5). Twenty-nine patients [median age 56 years, median 2 prior therapies, 14 chemoresistant (of 27 evaluable), 2 prior transplants] were enrolled and treated. The maximally tolerated vorinostat dose was defined as 500 mg twice daily × 5 d. Common dose limiting toxicities included infection (n = 2), hypokalaemia (n = 2), and transaminitis (n = 2). Grade 3 related gastrointestinal toxicity was seen in 9 patients. The median vorinostat concentration on day 3 was 4·5 μmol/l (range 4·2-6·0 μmol/l) and in vitro data confirmed the augmented antitumour and histone acetylation activity at these levels. Responses were observed in 19 of 27 evaluable patients (70%) including 8 complete response/unconfirmed complete response. High-dose vorinostat can be delivered safely with (R)ICE, achieves potentially synergistic drug levels, and warrants further study, although adequate gastrointestinal prophylaxis is warranted.
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Affiliation(s)
- Lihua E Budde
- Clinical Research Dvision, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
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13
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Brazeau NF, Pinto EG, Harvey HB, Oliveira GR, Pomerantz BJ, Wicky S, Oklu R. Critical limb ischemia: an update for interventional radiologists. Diagn Interv Radiol 2012; 19:173-80. [PMID: 23233402 DOI: 10.4261/1305-3825.dir.5955-12.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Critical limb ischemia (CLI) is a growing epidemic with bleak patient outcomes. A variety of treatment modalities have been adopted to address CLI based on comorbidities, life expectancy, and the nature of the arterial disease. With advances in technology and treatment strategies, the clinical outcomes of CLI patients have significantly improved over recent years. However, despite progress, patency rates of both surgical and endovascular interventions, limb-salvage and amputation rates are still dismal. We review the epidemiology, treatment strategies, imaging modalities, and the microcirculation aspect of CLI.
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Affiliation(s)
- Nicholas F Brazeau
- Department of Vascular Imaging and Intervention, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
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Stone JH, Patel VI, Oliveira GR, Stone JR. Case records of the Massachusetts General Hospital. Case 38-2012. A 60-year-old man with abdominal pain and aortic aneurysms. N Engl J Med 2012; 367:2335-46. [PMID: 23234517 DOI: 10.1056/nejmcpc1209330] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- John H Stone
- Division of Rheumatology, Allergy, and Immunology, Department of Medicine, Massachusetts General Hospital, Boston, USA
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Shriki JE, Shinbane JS, Rashid MA, Hindoyan A, Withey JG, DeFrance A, Cunningham M, Oliveira GR, Warren BH, Wilcox A. Identifying, characterizing, and classifying congenital anomalies of the coronary arteries. Radiographics 2012; 32:453-68. [PMID: 22411942 DOI: 10.1148/rg.322115097] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The clinical manifestations of coronary artery anomalies vary in severity, with some anomalies causing severe symptoms and cardiovascular sequelae and others being benign. Cardiovascular computed tomography (CT) has emerged as the standard of reference for identification and characterization of coronary artery anomalies. Therefore, it is important for the reader of cardiovascular CT images to be thoroughly familiar with the spectrum of coronary artery anomalies. Hemodynamically significant anomalies include atresia, origin from the pulmonary artery, interarterial course, and congenital fistula. Non-hemodynamically significant anomalies include duplication; high origin; a prepulmonic, transseptal, or retroaortic course; shepherd's crook right coronary artery; and systemic termination. In general, coronary arteries with an interarterial course are associated with an increased risk of sudden cardiac death. Coronary artery anomalies that result in shunting, including congenital fistula and origin from the pulmonary artery, are also commonly symptomatic and may cause steal of blood from the myocardium. Radiologists should be familiar with each specific variant and its specific constellation of potential implications.
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Affiliation(s)
- Jabi E Shriki
- South Sound Radiology, 3417 Ensign Rd NE, Olympia, WA 98506, USA.
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Silva WA, Gatto CC, Oliveira GR. (2E,4E)-1-(2-Hy-droxy-phen-yl)-5-phenyl-penta-2,4-dien-1-one. Acta Crystallogr Sect E Struct Rep Online 2011; 67:o2210. [PMID: 22058899 PMCID: PMC3200610 DOI: 10.1107/s160053681103025x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Accepted: 07/26/2011] [Indexed: 11/21/2022]
Abstract
In the structure of the title chalcone, C17H14O2, derived from cinnamaldehyde, the olefine group has a trans configuration. The molecular conformation is stabilized by an intramolecular O—H⋯O hydrogen-bond interaction with graph-set motif S(6).
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Oliveira GR, Teles BCV, Brasil EF, Souza MHLP, Furtado LETA, de Castro-Costa CM, Rola FH, Braga LLBC, Gondim FDAA. Peripheral neuropathy and neurological disorders in an unselected Brazilian population-based cohort of IBD patients. Inflamm Bowel Dis 2008; 14:389-95. [PMID: 17924556 DOI: 10.1002/ibd.20304] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND Several neurological disorders have been described in inflammatory bowel disease (IBD) patients, but their exact frequency is unknown. METHODS We prospectively studied the prevalence of neurological disorders (especially peripheral neuropathy) in a group of 82 patients with Crohn's disease (CD, n = 31) or ulcerative colitis (UC, n = 51) from 2 Brazilian tertiary care university clinics and followed them through a period of at least 1 year. All patients were interviewed and had complete neurological evaluations. RESULTS Large-fiber sensory or sensorimotor polyneuropathy (PN) was observed in 16.1% of the CD and 19.6% of the UC patients. PN was usually mild, predominantly symmetric, and distal with axonal involvement. One patient had demyelinating PN at the diagnosis of CD. Mild carpal tunnel syndrome was common in female UC patients. Sensory symptoms without electromyography abnormalities, suggestive of small-fiber neuropathy or subclinical myelopathy, affected 29% and 11.8%, respectively. After excluding other known etiological or contributory factors for PN, 13.4% of the IBD patients had otherwise unexplained large-fiber or small-fiber PN (7.3% with large-fiber SM PN). Nondebilitating headache was the most common neurological complaint. Three patients had ischemic strokes, 5 were epileptic, and 1 transient chorea. CONCLUSIONS Neurological disorders, especially PN, are common in our Brazilian cohort of IBD patients. They are diverse, multifactorial, and more common in women. Despite the mild phenotype in most cases, attention should be given by the general practitioner and gastroenterologist since they are frequently undiagnosed. Further studies are necessary to confirm these findings in populations with different genetic and nutritional backgrounds.
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Affiliation(s)
- G R Oliveira
- Hospital Universitário Walter Cantídio, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil
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19
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Silva FB, Monteiro ACS, Del Sarto RP, Marra BM, Dias SC, Figueira ELZ, Oliveira GR, Rocha TL, Souza DSL, da Silva MCM, Franco OL, Grossi-de-Sa MF. Proregion of Acanthoscelides obtectus cysteine proteinase: a novel peptide with enhanced selectivity toward endogenous enzymes. Peptides 2007; 28:1292-8. [PMID: 17485144 DOI: 10.1016/j.peptides.2007.03.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2007] [Revised: 03/21/2007] [Accepted: 03/22/2007] [Indexed: 11/29/2022]
Abstract
Acanthoscelides obtectus is a devastating storage insect pest capable of causing severe bean crop losses. In order to maintain their own development, insect pest larvae feed continuously, synthesizing efficient digestive enzymes. Among them, cysteine proteinases (CPs) are commonly produced as inactive precursors (procysteines), requiring a cleavage of the peptide proregion to become active. The proregion fits tightly into the active site of procysteines, efficiently preventing their activity. In this report, a CP cDNA (cpao) was isolated from A. obtectus midgut larvae. In silico studies indicated that the complete CP sequence contains a hydrophobic signal peptide, a prodomain and a conserved catalytic region. Moreover, the encoding cDNA contains 963bp translating into a 321 residue protein, CPAo, which was expressed in E. coli, fused with thioredoxin. Enzymatic assays using the recombinant protein revealed that the enzyme was catalytically active, being able to cleave the synthetic substrate Z-Phe-Arg-7-AMC. Additionally, this report also focuses the cpao propeptide (PCPAo) subcloning and expression. The expressed propeptide efficiently inhibited CPAo, as well as digestive CP of other bean bruchids. Little or no activity was found against proteolytic enzymes of two other coleopterans: Rhyzopertha dominica and Anthonomus grandis. The data reported here indicate the possibility of endogenous propeptides as a novel strategy on bruchids control, which could be applicable to bean improvement programs.
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Affiliation(s)
- F B Silva
- Embrapa Recursos Genéticos e Biotecnologia, Brasília-DF 70770-900, Brazil
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20
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Tolentino EC, Castro e Silva O, Zucoloto S, Souza MEJ, Gomes MCJ, Sankarankutty AK, Oliveira GR, Feres O. Effect of hyperbaric oxygen on liver regeneration in a rat model. Transplant Proc 2006; 38:1947-52. [PMID: 16908331 DOI: 10.1016/j.transproceed.2006.06.066] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Hyperbaric oxygen therapy is a treatment that has been gradually implemented for the treatment of several pathologic conditions. The present study evaluated the effect of hyperbaric oxygen therapy for hepatic regeneration and its relationship to mitochondrial function. Male Wistar rats underwent partial hepatectomy (70%) and subsequently underwent two sessions of hyperbaric oxygen (90 minutes each, at a pressure of 2 ATA). The animals were sacrificed at 24 and 48 hours after surgery. Hepatic regeneration was evaluated by the dry weight of the remaining liver, the hepatic regeneration rate, the hepatic DNA content, and the hepatocyte proliferation rate using the "proliferating cell nuclear antigen" (PCNA) content. Function of the mitochondria was evaluated by its oxygen consumption during respiratory states 3 and 4, its respiratory control ratio (RCR), its membrane potential, as well as its osmotic swelling. We also measured serum levels of aminotransferases. The results revealed an increased dry weight of the remaining liver, regeneration rate, and DNA content at 24 and 48 hours after hepatectomy. The hepatocyte proliferation rate was significantly higher among animals treated with hyperbaric oxygen therapy at 48 hours after surgery. There was no significant difference in aminotransferase levels. Mitochondrial respiration revealed reduced oxygen consumption in state 3 after 48 hours. These results demonstrated that hyperbaric oxygen stimulates hepatic regeneration at 24 and 48 hours after 70% hepatectomy. The effect of hyperbaric oxygen on hepatic tissue occurs without tissue damage and protects mitochondria after 48 hours.
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Affiliation(s)
- E C Tolentino
- Special Liver Transplantation Unit, Departments of Surgery and Anatomy, Ribeirão Preto School of Medicine, University of São Paulo, Avanida Bandeirantes 3.900, CEP 14049-900 Ribeirão Preto, São Paulo, Brazil
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21
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Castro e Silva O, Sankarankutty AK, Martinelli ALC, Souza FF, Teixeira AC, Feres O, Mente ED, Oliveira GR, Akita R, Muglia V, Elias J, Ramalho LNZ, Zucoloto S. Therapeutic Effect of Hyperbaric Oxygen in Hepatic Artery Thrombosis and Functional Cholestasis After Orthotopic Liver Transplantation. Transplant Proc 2006; 38:1913-7. [PMID: 16908321 DOI: 10.1016/j.transproceed.2006.06.062] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Among the postoperative complications, hepatic artery thrombosis can occur in up to 10% of adult orthotopic liver transplants and intervention is indicated when this occurs within 30 days by retransplantation. Primary graft dysfunction, which can occur in up to 30% of the cases and is another potential complication, although reversible, has a relatively high mortality rate. Hyperbaric therapy, an efficient mode of tissue oxygenation, is being used in an increasing number of clinical situations. We report here two cases where hyperbaric oxygen therapy greatly benefited patients with complications after orthotopic liver transplantation: one with hepatic artery thrombosis and the other with primary graft dysfunction. Both patients showed rapid clinical recovery with gradual reduction of liver and canalicular enzymes soon after commencing hyperbaric oxygen therapy.
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Affiliation(s)
- O Castro e Silva
- Special Liver Transplantation Unit, Departments of Surgery and Anatomy, Hospital das Clínicas, Ribeirão Preto School of Medicine, University of São Paulo, Av. Bandeirantes 3900, CEP 14049-900, Ribeirão Preto, São Paulo, Brazil.
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22
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Gondim FAA, Oliveira GR, Cruz-Flores S. Position-dependent levitation of the dominant arm after left parietal stroke: An unreported feature of posterior alien limb syndrome? Mov Disord 2005; 20:632-3. [PMID: 15726577 DOI: 10.1002/mds.20404] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
We describe a patient with an unreported feature of posterior alien limb phenomenon characterized by position-dependent levitation of the dominant arm exacerbated by tactile stimulation and associated with low-amplitude tremor of the fingers of the right hand in addition to a sensation of strangeness in the arm, secondary to a left parietal stroke.
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Affiliation(s)
- F A A Gondim
- Departamento de Fisiologia e Farmacologia, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil
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23
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Boin IFSF, Leonardi LS, Oliveira GR, Luzo ACM, Carvalho MA, Cardoso AR, Caruy CA. Gastrointestinal bleeding during liver transplantation--report of two cases. Hepatogastroenterology 2004; 51:1825-6. [PMID: 15532835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
A few authors have reported, especially as intraoperative complications, gastrointestinal hemorrhage related to liver transplantation. The aim of this study was to show two cases of gastrointestinal hemorrhage, which occurred during surgery. The first patient was male, 46 years old, with viral hepatic cirrhosis. He had previously presented two episodes of digestive bleeding. Upper digestive endoscopy showed esophageal gastric varices. During the hepatectomy there was bleeding inside the nasogastric tube associated with severe hemodynamics instability without other sources of bleeding. Intraoperative endoscopy evidenced bleeding gastric varices. Gastrectomy was carried out and the varices were tied. The piggyback technique was used in the liver transplantation. The surgery was concluded without problems and in the following four and a half years his condition has evolved well. In the second case, the patient was aged 17, female, with autoimmune hepatic cirrhosis. She had previously presented one episode of digestive bleeding. Intraoperative endoscopy showed median esophageal varices. During the anesthetic induction she presented an episode of hematemesis. A Sengstaken-Blakemore balloon was introduced. The transplant was performed without further problems. Her case has been followed for 14 months in the outpatients' clinic with a good postoperative course. To sum up, gastrointestinal hemorrhage can be due to portal hypertension during the liver transplantation and must be treated quickly. In these cases the surgery must be ongoing.
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Affiliation(s)
- I F S F Boin
- Unit of Liver Transplantation, Faculty of Medical Science, State University of Campinas (SP) Brazil
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Abstract
Fou rire prodromique (prodrome of crazy laughter) is a rarely described nosological entity. In 1903, Charles Féré, a French neurologist, introduced the term fou rire prodromique to describe pathological laughter heralding an apoplectic event. He was also among the first to describe gelastic epilepsy. His description was influenced by Edouard Brissaud, who supported the existence of a thalamic center for laughter regulation and suggested that spasmodic laughter and crying were due to lesions of the faisceau psychique (anterior internal capsule) or to irritation of the faisceau géniculé (corticobulbar tract). One hundred Years later, we review the evolution of the theories about pathological laughter and crying from Charles Bell in the early XIXth Century, up to the seminal works of Kinnier Wilson and James Papez and the era of modern neuroscience.
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Affiliation(s)
- F A A Gondim
- Department of Neurology, Saint Louis University School of Medicine, Missouri, USA
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Abstract
Spinal cord injury (SCI) leads to profound haemodynamic changes. Constant outflows from the central autonomic pattern generators modulate the activity of the spinal sympathetic neurons. Sudden loss of communication between these centers and the sympathetic neurons in the intermediolateral thoracic and lumbar spinal cord leads to spinal shock. After high SCI, experimental data demonstrated a brief hypertensive peak followed by bradycardia with escape arrhythmias and marked hypotension. Total peripheral resistance and cardiac output decrease, while central venous pressure remains unchanged. The initial hypertensive peak is thought to result from direct sympathetic stimulation during SCI and its presence is anaesthetic agent dependent. Hypotension improves within days in most animal species because of reasons not totally understood, which may include synaptic reorganization or hyper responsiveness of alpha receptors. No convincing data has demonstrated that the deafferented spinal cord can generate significant basal sympathetic activity. However, with the spinal shock resolution, the deafferented spinal cord (in lesions above T6) will generate life-threatening hypertensive bouts with compensatory bradycardia, known as autonomic hyperreflexia (AH) after stimuli such as pain or bladder/colonic distension. AH results from the lack of supraspinal control of the sympathetic neurons and altered neurotransmission (e.g. glutamatergic) within the spinal cord. Despite significant progress in recent years, further research is necessary to fully understand the spectrum of haemodynamic changes after SCI.
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Affiliation(s)
- F A A Gondim
- Departamento de Fisiologia e Farmacologia, Universidade Federal do Ceará, CP 3157, Rua Coronel Nunes de Melo, 1127 Fortaleza, Ceará Brazil.
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26
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Gondim FA, Oliveira GR, Graça JR, Gondim RB, Alencar HM, Dantas RP, Santos AA, Rola FH. Neural mechanisms involved in the delay of gastric emptying of liquid elicited by acute blood volume expansion in awake rats. Neurogastroenterol Motil 1999; 11:93-9. [PMID: 10320589 DOI: 10.1046/j.1365-2982.1999.00146.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We have previously reported that acute blood volume expansion in awake rats delays the gastric emptying of a liquid meal, using the phenol red method. In this study we attempted to investigate the neural mechanisms involved in this phenomenon. Blood volume expansion, due to Ringer-bicarbonate infusion up to a volume equivalent to 5% of body weight, decreased the gastric emptying of a liquid meal by half (38.2 +/- 1.8 vs 18.7 +/- 3.2%, P < 0.05). The blood volume expansion effect on gastric emptying of liquid was prevented by separate pretreatments, consisting of subdiaphragmatic vagotomy or i.v. injection of hexamethonium (20 mg kg-1) or yohimbine (3 mg kg-1). Intravenous injection of atropine (0.5 mg kg-1), guanethidine (10 mg kg-1), L-NAME (3 mg kg-1), prazosin (1 mg kg-1) or propranolol (2 mg kg-1) did not prevent the blood volume expansion effect on gastric emptying. Bilateral adrenalectomy or coeliac ganglionectomy were also ineffective. The results indicate that blood volume expansion decreases gastric emptying of liquid through vagal-dependent pathways, sensitive to hexamethonium and yohimbine. Evidence for the participation of the peripheral sympathetic nervous system was not found.
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Affiliation(s)
- F A Gondim
- Departamento de Fisiologia e Farmacologia, Faculdade de Medicina, Universidade Federal do Ceará, Fortaleza, Brasil
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Cardillo F, de Paula E, Oliveira GR, Marangoni S, Oliveira B, Meirelles NC. Erythrocruorin of Glossoscolex paulistus (Oligochaeta, Glossoscolecidae): modulation of oxygen affinity by specific antibodies. Biochem Mol Biol Int 1997; 41:497-509. [PMID: 9090457 DOI: 10.1080/15216549700201521] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
1) The Soret region absorption spectrum of erythrocruorin (ERC) obtained from Glossoscolex paulistus, shows that oxy-ERC has a maximum absorption peak at 416 nm while the deoxy-ERC from has a maximum at 427 nm. 2) In the presence of a specific antiserum (anti-ERC) and of anti-ERC immunoglobulin G raised in rabbits, there is a deviation to low wavelengths in the maximum absorption peak of deoxy-ERC while for the oxy form a red-shift is noticed. These shifts accompanied an increased affinity of the hemeprotein for oxygen, possibly because of changes in the overall macromolecular conformation. 3) A decrease in the oxygen affinity of erythrocruorin is observed when large amounts of non-specific serum are used. The same effect is observed in the presence of serum albumin, probably as a result of non-specific binding between the albumin and erythrocruorin. 4) The fluorimetric titration of erythrocruorin with anti-ERC Fab fragments results in a decrease in the intrinsic tryptophan fluorescence of the hemeprotein, a response indicative of a modification in the ERC's quaternary structure.
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Affiliation(s)
- F Cardillo
- Departamento de Bioquímica, Universidade Estadual de Campinas, C.P., Brasil
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