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A V Egorov

Publications and source records attributed to A V Egorov.

At least 19 recordsLinked to original sources
PubMed2006

[Diagnostics, treatment, and prevention of iatrogenic iodine-induced thyroid gland diseases].

The authors of the study investigated the effects of pharmacological doses of iodine as an ingredient of amiodaron, an anti-arrhythmic agent, and iodine radiopaque contrast agents (RCA), on the thyroid gland (TG) function. The subjects were 133 patients aged 60.5 +/- 8.5 years, who had been taking amiodaron for 12 to 164 months, and 164 patients aged 59.4 +/- 9.1 years, who were examined before coronarography (CAG) with RCA, and 1, 3, 6, and 12 months after the procedure. Serum levels of TSH, FT4, FT3, TG antibodies, TPO antibodies, and urine iodine level were measured; TG ultrasonography was performed. Forty-nine (51.9%) out of the 133 patients on amiodaron therapy developed thyroid disfunction. Subclinical hypothyroidism (24 cases; 18%) and manifest thyrotoxicosis (21 case; 15.8%) prevailed among functional TG disorders. Thirty-one per cent of the patients with thyrotoxicosis had preceding TG diseases; 70% of the thyrotoxicosis patients had a cardiac arrhythmia relapse. The concentration of thyroid antibodies did not change in patients with normal TG. The patients who underwent CAG displayed elevated renal iodine excretion 1, 3, and 6 months after RCA administration. Thyroid disfunction (thyrotoxicosis in 7.6% of the cases; hypothyroidism in 15.8% of cases) was revealed in 23.4% of the patients with preceding TG diseases one month after CAG. Cardial pathology exacerbation was observed in patients with thyrotoxicosis.

Amiodarone↗
PubMed2005

[Moot points of diagnosis and treatment of hormone-producing neuroendocrine tumors of pancreas].

Based on literature data and own experience of treatment of 225 patients with neuroendocrine tumors (NET) authors discuss moot points of diagnosis and treatment of this severe category of patients. It is demonstrated that the most appropriate algorithm of diagnosis before surgery is the combination of US with endoscopic US and angiography. Intraoperative diagnosis must be performed with intraoperative US and endoscopic transillumination. Authors demonstrate positive results of staged surgical treatment of MEN-1 syndrome. Malignant NET with distant metastases is not contraindication for surgical treatment. This situation is indication either for radical surgery with excision of all metastases or for cytoreductive surgery with subsequent chemoembolization and chemotherapy.

Algorithms↗
PubMed2002

[Diagnosis and treatment of gastrin-producing pancreatic tumors].

Current literature data on the clinical course, diagnosis and treatment of gastrinoma, one of the most frequent neuroendocrine tumors of the thyroid, as well as 23 cases with Zollinger-Ellison syndrome treated by the authors are analysed in detail. Peculiarities of the clinical course, difficulties of syndrome diagnosis, principles of updated topical diagnosis of gastrinoma, conservative and surgical treatments including treatment of multiple endocrine neoplasia syndrome are described.

Female↗
PubMed2000

[Intraoperative ultrasonography in surgery on organs of abdominal cavity and retroperitoneal space].

Since 1984 to 1999 intraoperative US examination (IOUSE) was made in 863 patients. 236 of them had diseases of the liver, 137 diseases of the gall bladder and biliary tract, 158 pancreatic disorders, 151 diseases of gastro-intestinal tract, 72 diseases of the adrenal glands, 101 constitutional obesity, 3 splenic disorders and 5 gunshot wounds of the organs of the abdominal cavity and the retroperitoneal soft tissues. In masses of the liver IOUSE showed limits for resection of the liver, location of the diseased area with the vessels and biliary ducts, unpalpablefoci. OUSE allowed to perform US-guided puncture and sclerosizing small metastatic nodes as well as a puncture and antiparasitic treatment of inaccessible echinococcal cysts. In cholelithiasis IOUSE allows to reveal or to rule out the presence of the concrements in bile ducts. In cases of diseases of the pancreas IOUSE helps to localize pathologic area, defines its interrelations with adjacent major vessels and ducts, reveals unpalpable masses and enables US-guided puncture of the major pancreatic duct followed by its further opening. In gastric tumors it is possible under US control to determine precisely the limits of the infiltration of gastric wall which defines the volume for resection. In operation on the adrenals from thoracophrenolumbar approach IOUSE through the diaphragmatic cupula determines the place and the length of phrenotomy and elucidates interrelations of the tumor with adjacent organs. Sensibility of IOUSE made up from 87 to 100%, and specificity--92-100% depending on the disease.

Abdomen↗
PubMed2000

[Treatment of malignant pancreatic islet cell tumors].

Among 142 patients with islet cell tumor who were admitted to hospital between 1982 and 1999, 15 patients (10.6%) had malignant tumours. The mean age was 45.3 +/- 5.8 years. Islet cell tumors were located in the head and corpus of the pancreas in 26.6% and 26.6% of the patients, respectively, in the tail of the pancreas in 46.8% of the patients. The mean size of the tumor was 2.9 +/- 0.7 cm, in 6 patients (40%) liver metastases were found. US, CT and angiography which sensitivity were 72.7, 100 and 85.7%, respectively, were used for topical diagnosis of the islet cell tumors. 12 patients were operated on (15 operations) and 3 patients were treated conservatively by streptozocin. Surgical procedures included distal pancreatic resection (n = 11), enucleation of the tumor (n = 2), hepatic resection (n = 1), abdominal exploration (n = 1). In 2 patients palliative pancreatic resections were combined with transarterial embolization and devascularisation of the liver metastases and 2 patients were treated by systemic chemotherapy. To reveal malignancy before and during the operation was possible only by evaluation of distant metastases and the adjacent organs infiltration. In other cases to determine the diagnosis was possible only after planned histological identification of the resected specimens. 5-year survival rates after conservative and surgical treatment were 33% and 62.5%, respectively. In patients without distant metastases 5-year survival rate was 100%.

Adult↗
PubMed2000

[Multiple endocrine neoplasia of the first type (Wermer's syndrome)].

11 patients with Wermer's syndrome (WS) aged 24-67 years were treated. They had a total of 30 tumors: 4(13.3%) hypophyseal, 11(36.7%) pancreatic, 9(30%) parathyroid, 4(13.3%) adrenal and 2(6.7%) duodenal. Each patient had two tumors minimum and 8 tumors maximum. In 8 cases WS presented clinically as hypoglycemia, in 3 cases as Zollinger-Ellison syndrome. The diagnosis was made using ultrasonography, CT, MRT and angiography. Cytogenetic examination was made in 2 cases. All the patients were operated. Six of them were operated two times, one--four times. The following surgery was made: 4 removals of parathyroid adenomas, 4 adrenalectomies, 1 removal of the hypophysis, 4 enucleations of pancreatic insulinomas, 5 distal hemipancreatectomies, 1 distal subtotal resection of the pancreas, 1 gastropancreatoduodenal resection. Clinically symptomatic tumors should be operated first.

Adult↗
PubMed1999

Subcellular muscarinic enhancement of excitability and Ca2+-signals in CA1-dendrites in rat hippocampal slice.

The cholinergic system is involved in Ca2+-dependent models of learning. To study subcellular modulation, we evoked 50-100 microm long dendritic Ca2+-responses by focal pressure application of glutamate. These Ca2+-responses were augmented by +70% by focally applied carbachol. This atropine-sensitive augmentation started within 1 s concurrent to an augmentation of the glutamate-evoked somatic depolarization and firing. Tetrodotoxin reduced the Ca2+-response to glutamate by 60-80% while, after having restored the Ca2+-signal by increasing the application of glutamate, its muscarinic augmentation was reduced from +73 to +30%. Lithium (2 mM, >2 h) slowed and reduced augmentation of Ca2+-signals and blocked augmentation of the glutamate-evoked depolarization and firing, but not suppression of the slow after-hyperpolarization following repetitive discharge. Thus, several mechanisms contribute to muscarinic augmentation of Ca2+-signals.

Acetylcholine↗
PubMed1999

Carbachol-induced changes in excitability and [Ca2+]i signalling in projection cells of medial entorhinal cortex layers II and III.

The entorhinal cortex (EC) is a major gateway for sensory information into the hippocampus and receives a cholinergic input from the forebrain. Therefore, we studied muscarinic effects on excitability and intracellular Ca2+ signalling in layer II stellate and layer III pyramidal projection neurons of the EC. In both classes of neurons, local pressure-pulse application of carbachol (1 mM) caused small, atropine-sensitive membrane depolarizations that were not accompanied by any detectable changes in [Ca2+]i. At a higher concentration (10 mM), carbachol induced a larger membrane depolarization associated with synaptic oscillations and epileptiform activity in both classes of neurons. In contrast to the intrinsic theta rhythm in stellate cells with one dominant peak frequency at approximately 7 Hz, the synaptically mediated oscillation induced by carbachol showed three characteristic peaks in the theta and gamma frequency range at approximately 11, 23 and 40 Hz. Although carbachol-induced epileptiform activity was associated with increases in intracellular free Ca2+ in both layer II and III cells, the observed [Ca2+]i accumulation was significantly larger in layer III than in layer II cells. Responses to intracellular current injections showed differences in Ca2+ accumulation in layer II and III cells at the same membrane potentials, suggesting a dominant expression of low- and high-voltage-activated Ca2+ channels in these layer II and III cells, respectively. In conclusion, we present evidence for significant differences in the [Ca2+]i regulation between layer II stellate and layer III pyramidal cells of the medial EC.

2-Amino-5-phosphonovalerate↗
PubMed1999

Muscarinic control of dendritic excitability and Ca(2+) signaling in CA1 pyramidal neurons in rat hippocampal slice.

The cholinergic system is critically involved in synaptic models of learning and memory by enhancing dendritic [Ca(2+)](i) signals. Diffuse cholinergic innervation suggests subcellular modulation of membrane currents and Ca(2+) signals. Here we use ion-selective microelectrodes to study spread of carbachol (CCh) after focal application into brain slice and subcellular muscarinic modulation of synaptic responses in CA1 pyramidal neurons. Proximal application of CCh rapidly blocked the somatic slow afterhyperpolarization (sAHP) following repetitive stimulation. In contrast, the time course of potentiation of the slow tetanic depolarization (STD) during synaptic input was slower and followed the time course of spread of CCh to the dendritic tree. With distal application, augmentation of the somatic STD and of dendritic Ca(2+) responses followed spread of CCh to the entire apical dendritic tree, whereas the sAHP was blocked only after spread of CCh to the proximal dendritic segment. In dendritic recordings, CCh blocked a small sAHP, augmented the STD, and rather reduced dendritic action potentials. Augmentation of dendritic Ca(2+) signals was highly correlated to augmentation of the STD. The NMDA receptor antagonist DL-2-amino-5-phosphonovaleric acid (APV) blocked approximately 55% of the STD in control and during CCh application. In conclusion, muscarinic suppression of the proximal sAHP can augment firing and thereby Ca(2+) responses. Dendritic augmentation of the STD by blockade of the sAHP and direct enhancement of N-methyl-D-aspartate (NMDA) receptor-mediated currents potentiates Ca(2+) signals even when firing is not affected due to suprathreshold input. In this way, subcellular muscarinic modulation may contribute to parallel information processing and storage by dendritic synapses of CA1 pyramidal neurons.

2-Amino-5-phosphonovalerate↗
PubMed1999

[Vipoma of pancreas].

Explore the source record for details and available documents.

Combined Modality Therapy↗
PubMed1999

[Diagnosis and surgical treatment of organic hyperinsulinism].

From 1982 to 1998 144 patients (males 31.7%, females 68.3%) with organic hyperinsulinism underwent surgery. Mean age of the patients was 44.2 +/- 4.6 years. The causes of the development of this disease were benign insulinoma (82.6%), malignant insulinoma (6.9%), beta-cells hyperplasia and microadenomatosis (4.2%). In 6.3% of the patients the origin of the disease was not established. The location of the insulinoma in the pancreatic head was detected in 33.8%, in the body--in 35.2%, in the tail--31%. The sensitivity of the used methods of topical diagnosis was the following: US--40.3%, CT--28.6%, angiography (selective celiacography and upper mesentericography)--76.9%, blood samples from the right hepatic vein after intraarterial stimulation of different parts of the pancreas by Ca with measurement of immunoreactive insulin level--87.2%, intraoperative palpation--86.5%, intraoperative US examination--100%. Preoperatively, the authors used combined angiographic examination, the sensitivity of which made up 94.9%, this study being a single one which allows to reveal the region of the lesion of the pancreas in beta-cells hyperplasy. Tumor enucleation (59 patients), distal resection of the pancreas (50), the excision of the insulinoma (25), duodenopancreatic resection (1), explorative laparotomy (9) were made. Postoperative complications rate arose in 43.6% of the patients, mortality rate--7.7%. The best results were achieved in enucleation of insulinoma and distal resection of the pancreas. The authors suggest that in preoperative diagnosis of insulinomas the preferable methods should be US-examination and combined angiographic examination. Intraoperative revision should be made with use of US examination. Depending on the intraoperative findings the preference should be given either to enucleation of insulinoma or to distal resection of the pancreas.

Adolescent↗
PubMed1998

Preoperative and intraoperative topographic diagnosis of insulinomas.

Altogether 120 patients with organic hyperinsulinism underwent clinical examination and treatment (38 male, 82 female, mean age 44.2 +/- 4.6 years). The cause of hyperinsulinism was benign insulinomas in 96 (80.0%), malignant tumors in 9 (7.5%), and hyperplasia of beta cells in 6 (5.0%). In 9 (7.5%) patients the origin of hyperinsulinism was not diagnosed. The tumor was localized in the head, body, and tail of the pancreas in 31.8%, 36.4%, and 31.8% of cases, respectively. Intraoperative ultrasonography (IOUS) was undertaken in 37 patients, and in 83 cases only intraoperative palpation was done. Arterial stimulated venous sampling (ASVS) was performed in 17 patients (blood was sampled from the right hepatic vein for determination of the insulin level after arterial stimulation by calcium gluconate in different parts of the pancreas). The sensitivity of ultrasonography (US) was 29.5%, computed tomography (CT) 24.2%, angiography 55.9%, superselective angiography (branches of the celiac trunk) 72.2%, and intraoperative palpation 90.0%. ASVS showed an accuracy of 90.0%. Combining angiography with ASVS gave an exact diagnosis of hyperinsulinism in 100% of cases, and IOUS revealed tumors in 100% of cases. Hyperplasia of beta-cells was diagnosed only by means of ASVS. A total of 117 patients underwent surgery, including distal resection of pancreas (n = 39), enucleation of tumor (n = 70), and laparotomy (n = 8). The postoperative mortality associated with insulinomas was 7.7%. The frequency of postoperative complications was 43.6%. Benign insulinomas recurred at a rate of 5.4%. Patients with malignant insulinomas had a 5-year survival of 66.0%. The diagnosis of insulinomas was achieved by a combination of selective angiography, ASVS, and IOUS.

Adult↗
PubMed1996

Muscarinic activation reduces changes in [Ca2+]o evoked by stimulation of Schaffer collaterals during blocked synaptic transmission in rat hippocampal slices.

The rat hippocampal slice preparation and blockers of postsynaptic glutamate receptors (6-nitro-7-sulphamoylbenzo(f)quinoxaline-2,3-dione (NBQX) 10 microM; DL-2-amino-5-phosphonovaleric acid (APV) 30 microM) were used to study the effects of muscarinic activation on stimulus-induced decreases in [Ca2+]o presumably due to presynaptic Ca-influx. Perfusion with carbachol (100-200 microM) transiently reduced these changes in [Ca2+]o. Blockade of this muscarinic effect by pirenzepine (200 microM) and prolongation of this effect after prolonged lithium (1 mM) incubation suggest involvement of the muscarinic M1 receptor subtype. These findings suggest, that activation of M1 receptors might contribute to inhibition of excitatory synaptic transmission by inhibiting presynaptic Ca-influx. In this way, the muscarinic enhancement of excitatory input may be limited to non-deleterious levels.

2-Amino-5-phosphonovalerate↗
PubMed1996

[Topical diagnosis of pancreatic insulinomas].

Diagnosis of pancreatic insulinomas has been performed. Celiacography appeared to be the most efficient diagnostic method (more than 50% of sensitivity). Intraoperative ultrasound testing, that have been done in 16 patients, managed to make a topical diagnosis with a high accuracy and to evaluate relation of a tumor with portal vessels and pancreatic duct that is very important in choosing a proper surgical technique.

Adult↗