MARIA CRISTINA CHAMMAS
Projetos de Pesquisa
Unidades Organizacionais
Instituto de Radiologia, Hospital das Clínicas, Faculdade de Medicina
LIM/44 - Laboratório de Ressonância Magnética em Neurorradiologia, Hospital das Clínicas, Faculdade de Medicina
LIM/44 - Laboratório de Ressonância Magnética em Neurorradiologia, Hospital das Clínicas, Faculdade de Medicina
6 resultados
Resultados de Busca
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- Increased prevalence of simple renal cysts in patients with gout(2013) HASEGAWA, Eduardo Massato; FULLER, Ricardo; CHAMMAS, Maria Cristina; MELLO, Filipe Martins de; GOLDENSTEIN-SCHAINBERG, ClaudiaThe aim of this study was to determine the prevalence of simple renal cysts in gout patients and evaluate associated risk factors for its development. Hundred and forty-six patients followed at our outpatient Gout Unit and 47 sex- and age-matched healthy kidney donors who had undergone routine renal ultrasonography, using a static gray scale and real-time B-mode units with a 3.5- or 5.0-MHz transducer, were evaluated for the presence of renal cysts. Demographic and clinical characteristics of gout patients were evaluated considering possible risk factors for the occurrence of simple renal cysts such as age, male gender, hypertension, and renal impairment. The prevalence of simple renal cyst was 26.0 % in gout patients and 10.6 % in control group (P = 0.045). Gout patients with simple renal cysts presented less renal lithiasis than those without this complication (5.2 vs 25.9 %; P = 0.003) in spite of an overall higher frequency of renal stones in gout patients compared to control group (20.5 vs. 6.3 %, P = 0.025). The presence of simple renal cyst in gout was not associated with previously reported factors such as age (P = 0.296), male predominance (P = 0.688), hypertension (P = 0.314), and renal impairment (P = 254). Moreover, no association with disease duration (P = 0.843) or tophi (P = 0.616) was observed. In conclusion, gout patients have an increased prevalence of simple renal cysts associated with a lower occurrence of nephrolithiasis. Whether renal cysts have any protective effect in the development of nephrolithiasis in gout remains to be determined.
- Safety of Ultrasound Contrast Agents in Patients With Known or Suspected Cardiac Shunts(2013) PARKER, Jeremy M.; WELLER, Mark W.; FEINSTEIN, Linda Maiman; ADAMS, Robin J.; MAIN, Michael L.; GRAYBURN, Paul A.; COSGROVE, David O.; GOLDBERG, Barry A.; DARGE, Kassa; NIHOYANNOPOULOS, Petros; WILSON, Stephanie; MONAGHAN, Mark; PISCAGLIA, Fabio; FOWLKES, Brian; MATHIAS, Wilson; MORIYASU, Fuminari; CHAMMAS, Maria Christina; GREENBAUM, Lennard; FEINSTEIN, Steven B.Contrast-enhanced ultrasound imaging is a radiation-free diagnostic tool that uses biocompatible ultrasound contrast agents (UCAs) to improve image clarity. UCAs, which do not contain dye, often salvage ""technically difficult"" ultrasound scans, increasing the accuracy and reliability of a front-line ultrasound diagnosis, reducing unnecessary downstream testing, lowering overall health care costs, changing therapy, and improving patient care. Two UCAs currently are approved and regulated by the US Food and Drug Administration. They have favorable safety profiles and risk/benefit ratios in adult and pediatric populations, including compromised patients with severe cardiovascular diseases. Nevertheless, these UCAs are contraindicated in patients with known or suspected right-to-left, bidirectional, or transient right-to-left cardiac shunts. These patients, who constitute 10% to 35% of the general population, typically receive no UCAs when they undergo echocardiography. If their echocardiographic images are suboptimal, they may receive inappropriate diagnosis and treatment, or they may be referred for additional diagnostic testing, including radiation-based procedures that increase their lifetime risk for cancer or procedures that use contrast agents containing dye, which may increase the risk for kidney damage. An exhaustive review of current peer-reviewed research demonstrated no scientific basis for the UCA contraindication in patients with known or suspected cardiac shunts. Initial safety concerns were based on limited rodent data and speculation related to macroaggregated albumin microspheres, a radioactive nuclear imaging agent with different physical and chemical properties and no relation to UCAs. Radioactive macroaggregated albumin is not contraindicated in adult or pediatric patients with cardiac shunts and is routinely used in these populations. In conclusion, the International Contrast Ultrasound Society Board recommends removal of the contraindication to further the public interest in safe, reliable, radiation-free diagnostic imaging options for patients with known or suspected cardiac shunts and to reduce their need for unnecessary downstream testing.
- Low-level laser in the treatment of patients with hypothyroidism induced by chronic autoimmune thyroiditis: a randomized, placebo-controlled clinical trial(2013) HOEFLING, Danilo B.; CHAVANTES, Maria Cristina; JULIANO, Adriana G.; CERRI, Giovanni G.; KNOBEL, Meyer; YOSHIMURA, Elisabeth M.; CHAMMAS, Maria CristinaChronic autoimmune thyroiditis (CAT) is the most common cause of acquired hypothyroidism, which requires lifelong levothyroxine replacement therapy. Currently, no effective therapy is available for CAT. Thus, the objective of this study was to evaluate the efficacy of low-level laser therapy (LLLT) in patients with CAT-induced hypothyroidism by testing thyroid function, thyroid peroxidase antibodies (TPOAb), thyroglobulin antibodies (TgAb), and ultrasonographic echogenicity. A randomized, placebo-controlled trial with a 9-month follow-up was conducted from 2006 to 2009. Forty-three patients with a history of levothyroxine therapy for CAT-induced hypothyroidism were randomly assigned to receive either 10 sessions of LLLT (830 nm, output power of 50 mW, and fluence of 707 J/cm(2); L group, n = 23) or 10 sessions of a placebo treatment (P group, n = 20). The levothyroxine was suspended 30 days after the LLLT or placebo procedures. Thyroid function was estimated by the levothyroxine dose required to achieve normal concentrations of T-3, T-4, free-T-4 (fT(4)), and thyrotropin after 9 months of postlevothyroxine withdrawal. Autoimmunity was assessed by measuring the TPOAb and TgAb levels. A quantitative computerized echogenicity analysis was performed pre- and 30 days postintervention. The results showed a significant difference in the mean levothyroxine dose required to treat the hypothyroidism between the L group (38.59 +/- 20.22 mu g/day) and the P group (106.88 +/- 22.90 mu g/day, P < 0.001). Lower TPOAb (P = 0.043) and greater echogenicity (P < 0.001) were also noted in the L group. No TgAb difference was observed. These findings suggest that LLLT was effective at improving thyroid function, promoting reduced TPOAb-mediated autoimmunity and increasing thyroid echogenicity in patients with CAT hypothyroidism.
- Guidelines and Good Clinical Practice Recommendations for Contrast Enhanced Ultrasound (CEUS) in the Liver - Update 2012 A WFUMB-EFSUMB Initiative in Cooperation With Representatives of AFSUMB, AIUM, ASUM, FLAUS and ICUS(2013) CLAUDON, M.; DIETRICH, C. F.; CHOI, B. I.; COSGROVE, D. O.; KUDO, M.; NOLSOE, C. P.; PISCAGLIA, F.; WILSON, S. R.; BARR, R. G.; CHAMMAS, M. C.; CHAUBAL, N. G.; CHEN, M. -H.; CLEVERT, D. A.; CORREAS, J. M.; DING, H.; FORSBERG, F.; FOWLKES, J. B.; GIBSON, R. N.; GOLDBERG, B. B.; LASSAU, N.; LEEN, E. L. S.; MATTREY, R. F.; MORIYASU, F.; SOLBIATI, L.; WESKOTT, H. -P.; XU, H. -X.Initially, a set of guidelines for the use of ultrasound contrast agents was published in 2004 dealing only with liver applications. A second edition of the guidelines in 2008 reflected changes in the available contrast agents and updated the guidelines for the liver, as well as implementing some non-liver applications. Time has moved on, and the need for international guidelines on the use of CEUS in the liver has become apparent. The present document describes the third iteration of recommendations for the hepatic use of contrast enhanced ultrasound (CEUS) using contrast specific imaging techniques. This joint WFUMB-EFSUMB initiative has implicated experts from major leading ultrasound societies worldwide. These liver CEUS guidelines are simultaneously published in the official journals of both organizing federations (i.e., Ultrasound in Medicine and Biology for WFUMB and Ultraschall in der Medizin/European Journal of Ultrasound for EFSUMB). These guidelines and recommendations provide general advice on the use of all currently clinically available ultrasound contrast agents (UCA). They are intended to create standard protocols for the use and administration of UCA in liver applications on an international basis and improve the management of patients worldwide.
- GUIDELINES AND GOOD CLINICAL PRACTICE RECOMMENDATIONS FOR CONTRAST ENHANCED ULTRASOUND (CEUS) IN THE LIVER - UPDATE 2012 A WFUMB-EFSUMB INITIATIVE IN COOPERATION WITH REPRESENTATIVES OF AFSUMB, AIUM, ASUM, FLAUS AND ICUS(2013) CLAUDON, Michel; DIETRICH, Christoph F.; CHOI, Byung Ihn; COSGROVE, David O.; KUDO, Masatoshi; NOLSOE, Christian P.; PISCAGLIA, Fabio; WILSON, Stephanie R.; BARR, Richard G.; CHAMMAS, Maria C.; CHAUBAL, Nitin G.; CHEN, Min-Hua; CLEVERT, Dirk Andre; CORREAS, Jean Michel; DING, Hong; FORSBERG, Flemming; FOWLKES, J. Brian; GIBSON, Robert N.; GOLDBERG, Barry B.; LASSAU, Nathalie; LEEN, Edward L. S.; MATTREY, Robert F.; MORIYASU, Fuminori; SOLBIATI, Luigi; WESKOTT, Hans-Peter; XU, Hui-XiongInitially, a set of guidelines for the use of ultrasound contrast agents was published in 2004 dealing only with liver applications. A second edition of the guidelines in 2008 reflected changes in the available contrast agents and updated the guidelines for the liver, as well as implementing some non-liver applications. Time has moved on, and the need for international guidelines on the use of CEUS in the liver has become apparent. The present document describes the third iteration of recommendations for the hepatic use of contrast enhanced ultrasound (CEUS) using contrast specific imaging techniques. This joint WFUMB-EFSUMB initiative has implicated experts from major leading ultrasound societies worldwide. These liver CEUS guidelines are simultaneously published in the official journals of both organizing federations (i.e., Ultrasound in Medicine and Biology for WFUMB and Ultraschall in der Medizin/European Journal of Ultrasound for EFSUMB). These guidelines and recommendations provide general advice on the use of all currently clinically available ultrasound contrast agents (UCA). They are intended to create standard protocols for the use and administration of UCA in liver applications on an international basis and improve the management of patients worldwide. (E-mail: Christoph.dietrich@ckbm.de) (C) 2013 World Federation for Ultrasound in Medicine & Biology.
- Thyroid disturbance related to chronic hepatitis C infection: role of CXCL10(2013) DANILOVIC, Debora Lucia Seguro; MENDES-CORREA, Maria Cassia; CHAMMAS, Maria Cristina; ZAMBRINI, Heverton; BARROS, Raffaelle K.; MARUI, SuemiAssociation between autoimmune thyroid diseases (AITD) and hepatitis C is controversial, but may occur or worsen during alpha-interferon treatment. The mechanism responsible for autoimmune diseases in infected patients has not been fully elucidated. This study aims to evaluate the frequency of AITD in chronic hepatitis C and the association of chemokine (CXC motif) ligand 10 (CXCL10) and AITD. One hundred and three patients with chronic hepatitis C and 96 controls were prospectively selected to clinical, hormonal, thyroid autoimmunity and ultrasound exams, besides thyroxine-binding globulin (TBG) and CXCL10 measurements and hepatic biopsies. The frequency of AITD among infected subjects was similar to controls. TT3 and TT4 distributions were right shifted, as was TBG, which correlated to both of them. Thyroid heterogeneity and hypoechogenicity were associated with AITD. Increased vascularization was more prevalent in chronic hepatitis C.CXCL10 was higher in infected patients (p=0.007) but was not related to thyroid dysfunction. Increase in CXCL10 levels were consistent with hepatic necroinflammatory activity (p=0.011). In summary, no association was found between chronic hepatitis C and AITD. Infected subjects had higher TT3 and TT4 which were correlated to TBG. Increased CXCL10 was not associated to thyroid dysfunction in HCV-infected population.