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PURPOSE: To describe a patient diagnosed with pheochromocytoma in the third trimester of pregnancy and discuss the perioperative and anesthetic management. CLINICAL FEATURES: A 32-yr-old previously healthy woman (gravida 4, para 2) presented to our tertiary care obstetrical hospital at 34 weeks five days gestation with a history of labile blood pressure and severe hypertension. A week prior to admission she began having episodes of severe headache, dizziness, sweating and nausea. On a routine obstetric visit she was noted to be severely hypertensive with a blood pressure of 200/120 mmHg. Biochemical investigations confirmed the diagnosis of pheochromocytoma and magnetic resonance imaging demonstrated a 3 cm x 3 cm right adrenal mass. The patient was invasively monitored in the intensive care unit and treated with alpha- followed by beta-blockade with phenoxybenzamine and metoprolol. A multidisciplinary conference was organized involving endocrinology, anesthesiology, general surgery and obstetrics to determine the most appropriate management of the patient. An uncomplicated laparoscopic adrenalectomy was performed following a period of recovery after an uneventful elective Cesarean delivery. CONCLUSIONS: The primary goals in the management of pheochromocytoma in pregnancy are early diagnosis, avoidance of a hypertensive crisis during delivery and definitive surgical treatment. Timing of surgical resection will depend on the gestational age at which diagnosis is made. Cesarean section is the preferred mode of delivery when the tumour is still present. This case illustrates that with antenatal diagnosis, advanced methods of tumour localization, adequate preoperative adrenergic blockade and team planning, pheochromocytoma in pregnancy can be treated successfully. 相似文献
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Molecular and genetic characterizations of five pathogenic and two non-pathogenic monoclonal antiphospholipid antibodies 总被引:3,自引:0,他引:3
Chukwuocha RU Zhu M Cho CS Visvanathan S Hwang KK Rahman A Chen PP 《Molecular immunology》2002,39(5-6):299-311
Antiphospholipid syndrome (APS) is an autoimmune disease that is characterized by thrombosis, recurrent fetal loss and thrombocytopenia. Antiphospholipid antibodies, detected by enzyme-linked immunoabsorbent assays (aCL) and/or in vitro blood clotting assays (LAC) are strongly associated with APS. Both the molecular structures used by pathogenic antiphospholipid antibodies and the genetic mechanisms leading to their production are unknown. We describe here the variable region genes of seven IgG antiphospholipid antibodies derived from two APS patients. Of these, five are pathogenic as defined in a mouse model of thrombosis and two are not. Analyses of the expressed variable region genes show no preferential V gene usage. However, similar to anti-DNA antibodies, pathogenic antiphospholipid antibodies contain an increased number of arginine residues in the third complimentarity-determining region (CDR3) of their H chains. The increased accumulation of arginine residues in the V(H) CDR3 may act to enhance antigen binding, promote disease and point to the importance of the H chain in the pathogenic potential of certain antiphospholipid antibodies. 相似文献
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Tissue images obtained at deeper depths lack significant contrast. To enhance the contrast of these images and to increase the visibility of subsurface tissues, a method is proposed. This technique is based on the principle that photons at longer wavelengths penetrate deeper than photons at shorter wavelengths. In this technique, images in the original and orthogonal polarized states are recorded with the source illumination in linear polarized state at two different wavelengths. Image subtraction of a fraction of the copolarized image from the perpendicular polarized state is done on these images. The images obtained after the first processing are subjected to the next image subtraction where the shorter wavelength image is subtracted from the longer wavelength image. Monte Carlo simulations show that the resultant image has marked contrast up to 2.5 cm. 相似文献
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Ganta SR Piesco NP Long P Gassner R Motta LF Papworth GD Stolz DB Watkins SC Agarwal S 《Journal of biomedical materials research. Part A》2003,64(2):242-248
Urethanes are frequently used in biomedical applications because of their excellent biocompatibility. However, their use has been limited to bioresistant polyurethanes. The aim of this study was to develop a nontoxic biodegradable polyurethane and to test its potential for tissue compatibility. A matrix was synthesized with pentane diisocyanate (PDI) as a hard segment and sucrose as a hydroxyl group donor to obtain a microtextured spongy urethane matrix. The matrix was biodegradable in an aqueous solution at 37 degrees C in vitro as well as in vivo. The polymer was mechanically stable at body temperatures and exhibited a glass transition temperature (Tg) of 67 degrees C. The porosity of the polymer network was between 10 and 2000 microm, with the majority of pores between 100 and 300 microm in diameter. This porosity was found to be adequate to support the adherence and proliferation of bone-marrow stromal cells (BMSC) and chondrocytes in vitro. The degradation products of the polymer were nontoxic to cells in vitro. Subdermal implants of the PDI-sucrose matrix did not exhibit toxicity in vivo and did not induce an acute inflammatory response in the host. However, some foreign-body giant cells did accumulate around the polymer and in its pores, suggesting its degradation is facilitated by hydrolysis as well as by giant cells. More important, subdermal implants of the polymer allowed marked infiltration of vascular and connective tissue, suggesting the free flow of fluids and nutrients in the implants. Because of the flexibility of the mechanical strength that can be obtained in urethanes and because of the ease with which a porous microtexture can be achieved, this matrix may be useful in many tissue-engineering applications. 相似文献
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Sudha Sumi Mitra Krishnapillai Sreekumar 《Macromolecular chemistry and physics.》1997,198(5):1611-1621
Poly[N-(2-aminoethyl)acrylamido]triethylammonium dichloroiodate, tetrachloroiodate and dibromoiodate resins have been developed as a new class of heterogeneous reagents. The use of the polyhalide derivatives for the selective iodination of aromatic amines and phenols is described. The influence of the various reaction parameters including nature of the solvent, effective molar concentration of the reagent and temperature were investigated to find out the optimum reaction conditions for achiveing selectivity for monoiodination. 相似文献
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