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61.
ABSTRACT A simple and practical provocative test is needed for early asymptomatic pheochromocytoma, which is a major risk for patients with multiple endocrine neoplasia type 2 (MEN-2). We measured plasma catecholamines before and after submaximal exercise in 26 MEN-2 gene carriers, eight of whom with asymptomatic pheochromocytoma, nine with medullary thyroid carcinoma and 10 after uni- or bilateral adrenalectomy. Seventeen clinically healthy individuals and 11 patients with neurovegetative lability and symptoms mimicking pheochromocytoma served as controls. Plasma adrenaline, noradrenaline and dopamine increased after excercise except for adrenaline after bilateral adrenalectomy. The post-exercise levels of adrenaline and the adrenalineldopamine ratio were significantly higher in the pheochromocytoma patients compared to the healthy controls and the patients with neurovegetative lability, while the patients with medullary thyroid carcinoma represented an intermediate group with a high probability of developing adrenal tumors. The present method is a physiological test with a high sensitivity and specificity. It is practical and well suited for repeated examinations and seems to be of value for the detection of early pheochromocytoma in MEN-2 patients. Furthermore, the test could be used in the differential diagnosis between pheochromocytoma and neurovegetative lability.  相似文献   
62.
目的:探讨腹腔镜下手术治疗肾上腺嗜铬细胞瘤围手术期护理方法方法:对56例肾上腺嗜铬细胞瘤患者行手术治疗,并给予密切的术前术后护理,结果,本组均于腹腔镜下手术治疗,均经后腹腔镜途径(其中两例中属开放手术)。术后一例出现肾上腺危象,经及时处理,顺利康复;其余患者无严重并发症的发生。随访12~30个月,复查B超,CT未见复发。结论:充分的术前准备及细致的术后护理是患者早日康复的关键。  相似文献   
63.
The neuroprotective effects of Jatrorrhizine from Coptidis Rhizoma against hydrogen peroxide (H(2)O(2))-induced rat pheochromocytoma line PC12 injury and its potential mechanisms were evaluated in the present study. When cells were exposed to H(2)O(2) (200 μM) for 12h, there was a significant reduction in cell survival and activity of antioxidant enzyme (SOD and HO-1) and LDH release. In addition, increased ROS production, declined MMP and increased production of malondialdehyde (MDA) were observed. Preincubation of cells with Jatrorrhizine (0.01-10.0 μM) 24h prior to H(2)O(2) exposure markedly elevated cell viability and activities of antioxidant enzyme (SOD and HO-1), prevented LDH release and lipid peroxidation (MDA) production, attenuated the decrease of MMP and scavenged ROS formation. Jatrorrhizine also attenuated caspase-3 activation of the downstream cascade following ROS. Our results suggest that Jatrorrhizine holds potential for neuroprotective effects against H(2)O(2)-induced injury.  相似文献   
64.
Objective To investigate the clinical and genetic features of a Chinese family with yon Hippel- Lindau (VHL) disease revealed by bilateral pheochromocytoma. Methods The proband and other members in a Chinese family with familial pheochromocytoma were clinically evaluated and followed up. Genomic DNA extracted from the peripheral blood of 8 family members (including 3 patients) was amplified by polymerase chain reaction (PCR) and the PCR products were directly sequenced. Results The first presentation in the proband, his mother, and his sister was bilateral pheochromocytoma, and the missense mutation of 695G-A (Arg161Gln) in exon 3 of VHL gene was detected in the three patients. In the follow-up study, the proband and his mother were found to have other VHL tumors, induding retinal and cerebellar hemangioblastomas and pancreatic tumor. Neither clinical presentation of VHL disease nor gene mutation was found in other family members. Conclusion VHL disease should be suspected in some patients with familial pheochromocytoma, and VHL gene screening helps to achieve early diagnosis of the disease.  相似文献   
65.
66.
目的通过检测类肝素酶-1(HPA)、血管内皮生长因子(VEGF)在良、恶性嗜铬细胞瘤中的表达情况,探讨HPA、VEGF能否成为预测恶性嗜铬细胞瘤的指标,并阐明二者间的关系。方法选取1986年10月~2006年8月住院经手术治疗,且具有完整的临床、病理和随访资料的嗜铬细胞瘤患者存档石蜡标本38例,其中良性嗜铬细胞瘤21例,恶性嗜铬细胞瘤17例。恶性嗜铬细胞瘤组中首次手术确诊为嗜铬细胞瘤后随访28~179个月;良性嗜铬细胞瘤组中首次手术确诊为嗜铬细胞瘤后随访93~264个月。另取20例因良性肾疾患行肾切除时获取的同侧正常肾上腺组织作为对照组。采用免疫组织化学技术,检测良、恶性嗜铬细胞瘤及20例正常肾上腺髓质组织中HPA和VEGF的表达情况。结果HPA在恶性嗜铬细胞瘤中高表达(76.47%),在良性嗜铬细胞瘤中表达较低(28.57%),在正常肾上腺髓质组织中无表达,恶性嗜铬细胞瘤组与良性嗜铬细胞瘤组及恶性嗜铬细胞瘤组与正常。肾上腺髓质组织组之间HPA的表达有显著性差异(P〈0.05)。VEGF在恶性嗜铬细胞瘤中呈高表达,阳性率为82.40%,在良性嗜铬细胞瘤和正常。肾上腺髓质组织中的阳性率分别为23.80%、5.00%,VEGF在恶性嗜铬细胞瘤中的表达与在良性嗜铬细胞瘤和正常肾上腺髓质组织中的表达有显著性差异(P〈0.05)。在嗜铬细胞瘤中HPA与VEGF的表达呈正相关。结论HPA和VEGF有望成为预测恶性嗜铬细胞瘤的指标。  相似文献   
67.
Background Adrenal ganglioneuroma is a rare adrenal pathogenic disease with difficult differential diagnosis from adrenal pheochromocytoma. Currently, very limited literature is available to allow a differential diagnosis of these two conditions from each other. This study aimed to evaluate the clinical profile, differential diagnosis and surgical treatments of both conditions. Methods Clinical characteristics of 36 patients with adrenal pheocheomocytoma and 18 patients with adrenal ganglioneuroma were analyzed. Data from CT scans and surgical treatments from 1999 to 2007 were collected. Endocrine hormone tests and ^131I-metaiodobenzylguanidine (MIBG) were performed. Neither ^131I-MIBG nor endocrine hormone tests were available in 9 cases of asymptomatic adrenal ganglioneuroma with tumor size less than 4 cm and there were negative findings from contrast enhanced CT scans. The level of urine catecholamine of patients was compared by one-way analysis of variance. Results The mean age of patients in the adrenal ganglioneuroma group was 41.2 years (16-67 year) and in the adrenal pheochromocytoma patients 38 years (17-74 year). Contrast enhanced CT showed that the foci were intensified in 5 cases (27.8%) of adrenal ganglioneuroma and there were obvious contrast indications in 30 (83.3%) of the pheochromocytoma. Catecholamine levels in a 24-hour urine sample were normal in 4 patients with adrenal ganglioneuroma and increased in 36 (100%) cases with adrenal pheochromocytoma. ^131I-MIBG nuclear scan showed negative results in 4 patients (100%) with adrenal ganglioneuroma and positive results in 25 (96.2%) with adrenal pheochromocytom. Laparoscopy for adrenal tumors was performed through a transperitoneal or retroperitoneal approach during a follow-up period of (43±6) months, and all cases survived well. Conclusions CT, urinary catecholamine and ^131I-MIBG are standard and efficient tools for differential diagnosis of adrenal ganglioneuroma from pheochromocytoma. Laparoscopic surgery can be performed through a transperitoneal or retroperitoneal approach depending on the finding of CT scans. Open surgery is necessary for patients with blood loss of more than 800 ml and violent fluctuation of intraoperative blood pressure.  相似文献   
68.
We investigated the effects of IgG anti-GalNAc-GD1a antibodies, produced by immunizing rabbits with GalNAc-GD1a, on the voltage-dependent calcium channel (VDCCs) currents in nerve growth factor (NGF)-differentiated PC12 pheochromocytoma cells. VDCCs currents in NGF-differentiated PC12 cells were recorded using the whole-cell patch-clamp technique. Immunized rabbit serum that had a high titer of anti-GalNAc-GD1a antibodies inhibited the VDCCs currents in the NGF-differentiated PC12 cells (36.0+/-9.6% reduction). The inhibitory effect of this serum was reversed to some degree within 3-4 min by washing with bath solution. Similarly, application of purified IgG from rabbit serum immunized with GalNAc-GD1a significantly inhibited the VDCCs currents in PC12 cells (30.6+/-2.5% reduction), and this inhibition was recovered by washing with bath solution. Furthermore, the inhibitory effect was also observed in the GalNAc-GD1a affinity column binding fraction (reduction of 31.1+/-9.85%), while the GalNAc-GD1a affinity column pass-through fraction attenuated the inhibitory effect on VDCCs currents. Normal rabbit serum and normal rabbit IgG did not affect the VDCCs currents in the PC12 cells. In an immunocytochemical study using fluorescence staining, the PC12 cells were stained using GalNAc-GD1a binding fraction. These results indicate that anti-GalNAc-GD1a antibodies inhibit the VDCCs currents in NGF-differentiated PC12 cells.  相似文献   
69.
Pheochromocytoma can present with right hypochondrial pain, elevated liver enzymes, and a misleading appearance on ultrasound scan mimicking hepatic mass due to the proximity of adrenal masses to the liver.  相似文献   
70.
Kudzu root (Gegen in Chinese) is the dried root of Pueraria lobata (Willd.) Ohwi, a semi-woody, perennial and leguminous vine native to South East Asia. It is often used interchangeably in traditional Chinese medicine with thomson kudzu root (Fengen in Chinese), the dried root of P. thomsonii, although the Chinese Pharmacopoeia has separated them into two monographs since the 2005 edition. For more than 2000 years, kudzu root has been used as a herbal medicine for the treatment of fever, acute dysentery, diarrhoea, diabetes and cardiovascular diseases. Both English and Chinese literatures on the traditional applications, phytochemistry, pharmacological activities, toxicology, quality control and potential interactions with conventional drugs of both species have been included in the present review. Over seventy phytochemicals have been identified in kudzu root, with isoflavonoids and triterpenoids as the major constituents. Isoflavonoids, in particular puerarin, have been used in most of the pharmacological studies. Animal and cellular studies have provided support for the traditional uses of kudzu root on cardiovascular, cerebrovascular and endocrine systems, including diabetes and its complications. Further studies to define the active phytochemical compositions, quality standards and clinical efficacy are warranted. Strong interdisciplinary collaboration to bridge the gap between traditional medicine and modern biomedical medicine is therefore needed for the development of kudzu root as an effective medicine for the management of diabetes and cardiovascular diseases.  相似文献   
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