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1.
The influence of ribonuclease on the morphogenesis of experimental pancreatitis in the albino rats has been studied. The drug injected during edematous stage of pancreatitis caused some decrease of pancreatic enzymes level in the blood at hemorrhagic stage and its normalization at necrotic stage of pancreatitis. The development of hemorrhagic and necrotic stages of pancreatitis did not change under the influence of ribonuclease. The maturation of connective tissue of pseudocyst capsule was delayed and inflammatory infiltration of necrotic tissues and their elimination were increased under the influence of the drug. There were extensive tubular transformations of acini and early fibrosis and lipomatosis in the frontier zone. In the viable parts of pancreas moderate hypertrophy of exocrine pancreatocytes developed and chronic pancreatitis features appeared with use of ribonuclease.  相似文献   

2.
Early treatment with gordox of white rats with experimental pancreonecrosis reduces amylasemia and prevents dissemination of steatonecroses. The drug appreciably improves pancreatic microcirculation. Similarly to the control, the injured part of the gland undergoes necrosis. However, the severity of hemorrhagic component is minimal. The treatment with gordox enhances leukocytic infiltration aimed at elimination of necrotic tissues.  相似文献   

3.
Histological and electron microscopic studies of canine pancrease were conducted with biochemical control of pancreatic enzyme activity before and after treatment of experimental hemorrhagic pancreatonecrosis. 30-60 minutes after the disease induction microfocal pancreatonecrosis was revealed, while 6-8 hours later subtotal hemorrhagic pancreatonecrosis with changes in microcirculatory vessels of the pancreas manifested in erythrostasis, thrombosis and fibrinoid wall necrosis accompanied by the increase of pancreatic enzyme activity and decrease in blood, lymph and serum antienzyme activity developed. The treatment of experimental pancreatonecrosis with endolymphatic injection of contrical resulted in the morphologically confirmed attenuation of the necrosis intensity, limitation of necrotic zone size, blood circulation recovery in microcirculatory system, marked decrease of proteolytic enzyme activity and increase of blood serum and central lymph antienzyme activity.  相似文献   

4.
Experiments carried out on 91 dogs have shown that changes in the inflammatory process course result in complicated postinfarction repair of myocardium, disagreement in the development, i.e. in desynchronization of necrotic repair processes in the myocardial infarction zone. It is supposed that regulation of the myocardial infarction healing by inflammation can be one of the efficient methods of its therapy.  相似文献   

5.
Experiment on 72 dogs has shown that myocardial infarction (M1) against a background of hyperglycemia proceeds as shifts healing hyperactive MI. Shifts in carbohydrate metabolism results in disturbances of dynamics of the necrotic infarction zone processes that induces complications of healing changes in the content of myoglobin, creatine kinase, aspartateaminotransferase with MI against a background of hyperglycemia greatly differ from those typical of noncomplicated and complicated hyperactive MI.  相似文献   

6.
Based on experimental studies the possibility of cordialin use in acute ischemia is being substantiated. On the first day of the animals' mortality and increased life duration of cells in ischemia zone, delaying the injury region expansion. But later in rats, that were given cordialin, slowing down of injury zone recovery and scar tissue formation was demonstrated. Cordialin use in early stages of myocardial infarction is suggested. In experiments on isolated heart cordialin is reported to decrease the intensity of processes of lipids' peroxide oxidation in intact and ischemic myocardium. But in reperfusion cordialin activates LPO, that is associated with heart contracting activity inhibition. The results of the study may serve as an experimental basis for cordialin use on the first day of MI development. Its further use needs the correction of its ability to slow down the processes of necrotic tissue recovery.  相似文献   

7.
ABSTRACT: Centrally necrotizing carcinoma is a rare subtype of breast carcinoma, which is characterized by an extensive central necrotic zone accounting for at least 70% of the cross-sectional area of the neoplasm. This central necrotic zone, in turn, is surrounded by a narrow rim of proliferative viable tumor cells. We report an unusual clinical situation in which a patient whose evident breast mass suggested an ipsilateral local recurrence and for which numerous attempts to confirm the histological diagnosis had failed. The patient was treated with a radical mastectomy based on clinical suspicion of breast cancer recurrence after an undesirable delay. In this case, the narrow rim of viable malignant tissue had a thickness of 0.5 to 8 mm, and the centrally necrotizing carcinoma had a central zone with a predominance of fibrosis. The special features of this case led to a misdiagnosis and to an evident clinical local recurrence.  相似文献   

8.
The experiment on 39 dogs has shown that in MI the concentration dynamics of conjugates in the blood plasma is in accordance with the forms of its healing and has two periods of activation related, respectively, to necrotic processes and development of granular tissue in the infarction zone. The control over the changes of peroxide lipid oxidation (PLO) in MI may be regarded as one of the methods of diagnosing and foreseeing the outcomes of its healing. In optimization of MI healing, to modulate PLO appears to be advisable, that is, to make its course typical of noncomplicated MI.  相似文献   

9.
Spiral scanning computed tomography (CT) is able not only to image the pancreas and to evaluate its structure, but to interpret the status of the adjacent organs and tissues. CT symptoms of pancreatic necrotic changes and multiorgan failure were studied in the prospective follow-up of 47 patients with prior destructive pancreatitis (158 studies). CT differentially substantiated indications for choosing treatment policy for different forms of pancreatic lesions. The paper gives a quantitative assessment of necrotic pancreatic parencymatous areas and shows its prognostic value.  相似文献   

10.
Reactive oxygen and nitrogen species (ROS and RNS) play an important role in signal transduction and cell injury processes. Nitric oxide synthase (NOS)-the key enzyme producing nitric oxide (NO)-is found in neuronal structures, vascular endothelium and, possibly, in acinar and ductal epithelial cells in the pancreas. NO is known to regulate cell homeostasis, and its effects on the acinar cells are reviewed here. ROS are implicated in the early events within the acinar cells, leading to the development of acute pancreatitis. The available data on ROS/RNS involvement in the apoptotic and necrotic death of pancreatic acinar cells will be discussed.  相似文献   

11.
Summary Ossification of calvariae from day-21 rat fetuses was reinvestigated by electron microscopy using different fixation techniques (glutaraldehyde/OsO4, tannic acid, ruthenium red, K-pyroantimonate). An osteoid layer with scattered mineral deposits was found at the mineralization front. Directly beyond this layer, a sheet of one to two layers of necrotic and degenerating osteoblasts was present. Above this sheet, normal and healthy cells were seen, formed by six to eight layers of flattened cells, embedded in a collagenous matrix. The osteoblasts on the less mineralizing opposite side of the calcified cavariae and the osteocytes embedded in the calcified calvariae appeared healthy. Closer inspection of the necrotic zone revealed apatite crystal in vesicles which most probably originated from mitochondria of the degenerated cells. Large K-pyroantimonate deposits were found throughout the osteoid and the necrotic zone, whereas only small granules were scattered in the cytoplasm and at the plasma membrane of the healthy cells directly adjacent to the necrotic zone. A concept of intramembranous mineralization is outlined, according to which osteoblasts store enormous amounts of calcium, which are liberated by physiological cell death in the vicinity of the mineralizing front.  相似文献   

12.
The present study examines the morphological changes occurring in subcutaneous pancreatic tissue grafts (SPTG) and its effect on the host pancreatic islet cells in streptozotocin (STZ)-induced diabetic rats using morphological techniques. SPTG survived after 15 weeks of transplantation. Its acinar cells degenerated but the ducts and endocrine cells survived. The surviving and newly formed pancreatic tubules and endocrine cells filled the spaces left by degenerated acinar cells. Compartmentalization of the surviving parenchymatic tissues was observed, with the pancreatic tubules lying in the periphery of the graft and the endocrine tissue in the inner portion of the graft. Lymphocytes invaded the inner portion of the graft, conglomerating around endocrine cells. It was interesting, however, that, lymphocytes where not observed in the periphery of the grafts where most of the surviving pancreatic tubules lie. In addition to this, necrotic tissues were observed in the inner part of the graft. Fifteen weeks after transplantation into the subcutaneous region, insulin, glucagon, somatostatin and pancreatic polypeptide-immunoreactive cells were observed in many parts of the graft. In the peripheral parts of the grafts, large numbers of pancreatic tubules differentiated into endocrine cells. In conclusion, the ductal and endocrine cells of pancreatic tissue fragments survived in the subcutaneous region of rat with normal pattern of distribution.  相似文献   

13.
Effects of single, whole-body 60Co-gamma irradiation in different doses (250 rad to 15 k rad) on histology of thyroid, adrenal and pancreatic islets of the rain quail were studied. A low dose of 250 rad failed to evoke any change in histology of the glands studied. Doses of 500 rad and 1 k rad resulted in hypoactivity of thyroid but could not affect adrenal and pancreatic islets. Exposure to 1.5 k rad and higher doses caused hyperplasia and hypertrophy of thyroid and hypertrophy of adrenal gland. Thyroid was injured by heavy irradiation. Doses up to 3 k rad did not bring about any change in islet cells, however, higher doses resulted in degenerative changes in islet cells. alpha-islets were affected by 7 and 15 k rad but necrotic changes in beta-islets were observed only after exposure to 15 k rad. The results indicate that thyroid is the most sensitive and pancreatic islet, highly resistant to gamma radiation.  相似文献   

14.
Mechanisms of cardiac regeneration following transmural myocardial infarction were analysed in rat hearts using immunohistochemistry for a-SMA, caspase-3, Ki-67 and nestin markers. Seven weeks after experimental myocardial infarction, two different types of healing processes were revealed in rats with and without aneurysmatic bulging of the left ventricular wall. Besides thinning of the ventricular wall, three zones characterized both types of scars: the scar zone (divided into central and peripheral parts), the peri-infarct zone and the border zone. The main difference between the types of scars was the presence of a central necrotic zone inside the aneurysmatic wall, while connective tissue with myofibroblasts characterized the same zone in non-bulging wall. Apoptotic caspase-3 positive cells were found in the granulation tissue of the border zone in aneurysmatic scar, while in non-bulging scar they characterized all three zones. Proliferating Ki-67 positive cells displayed reverse expression pattern compared to apoptotic cells. Quantification of a-SMA positive cells revealed 60% a-SMA positive cells inside the central part of the aneurysmatic scar zone and 39% in invaginating areas, versus 19% in non-invaginating areas of the peripheral zone, but only 30% in the peripheral part of the non-bulging scar zone. Nestin positive cells were found in both types of scars, but with different distribution. These results suggest that even seven weeks after myocardial infarction, the healing processes in non-bulging scars are in chronic phase, while aneurysmatic scars are still in subacute phase. Histological differences in scar healing might be important for functional properties of the heart wall and for heart recovery prognosis.  相似文献   

15.
Fairy ring is a frequently reported disease of turfgrasses worldwide, and necrotic or severely injured grass are observed in those turf sites exhibiting type-I fairy ring symptoms. The objective of this research was to characterize soil chemical and physical properties at two soil sampling depths (0.5 cm and 3.0 cm) at a turfgrass site exhibiting type-I fairy ring symptoms. Soil samples were obtained from a perennial ryegrass (Lolium perenne L.) golf course fairway at one sampling date in the summer when environmental conditions were most conducive to the appearance of severe type-I fairy ring symptoms. At both soil depths, soil analysis indicated that concentrations of ammonium-nitrogen, potassium, and sulfur were statistically higher in soil underlying necrotic or bare zones versus soil in healthy turfgrass zones. At both soil depths, soil electrical conductivity was statistically higher, and volumetric soil water content was statistically lower in necrotic zones versus soil under healthy turfgrass. At both soil depths, total nitrogen, magnesium, calcium, cation exchange capacity, and organic matter content were not statistically different among necrotic and healthy turfgrass zones. Soil pH was statistically higher in the necrotic zone versus soil under healthy turfgrass at only the 3.0 cm soil sampling depth. Comparing soil properties within the necrotic zone, only potassium and electrical conductivity was statistically higher at the 0.5 cm depth compared to the 3.0 cm depth. Although most soil information was considered very similar at both sampling depths, soil sampling at the 3.0 cm depth would be a more practical or easier method for turfgrass managers. At either soil sampling depth, the necrotic zones of type-I fairy ring areas in turfgrass were most likely associated with a combination of direct and indirect effects of the basidiomycete fungi on soil chemical and physical properties in the turfgrass root zone. Presented at the International Conference on Biohydrology, Prague, Czech Republic, 20–22 September 2006.  相似文献   

16.
Lipids play a role in acute pancreatitis (AP) progression. We investigate the ability of pancreatic acinar cells to trigger inflammatory response in the presence of lipid compounds generated in necrotic areas of peripancreatic adipose tissue (AT) during AP induced in rats by 5% sodium taurocholate. Lipid composition of AT was analyzed by HPLC–mass spectrometry. Acinar inflammatory response to total lipids as well as to either the free fatty acid (FFA) fraction or their chlorinated products (Cl-FFAs) was evaluated. For this, mRNA expression of chemokine (C-C motif) ligand 2 (CCL2) and P-selectin as well as the activation of MAPKs, NF-κB and STAT-3 were analyzed in pancreatic acini. Myeloperoxidase (MPO) activity, as an inducer of Cl-FFA generation, was also analyzed in AT. MPO activity significantly increased in necrotic (AT-N) induced changes in lipid composition of necrotic fat, such as increase in FFA and phospholipid (PL) content, generation of Cl-FFAs and increases in saturated FFAs and in the poly-:mono-unsaturated FFA ratio. Total lipids from AT-N induced overexpression of CCL2 and P-selectin in pancreatic acini as well as MAPKs phosphorylation and activation of NF-κB and STAT3. FFAs, but not Cl-FFAs, up-regulated CCL2 and P-selectin in acinar cells. We conclude that FFAs are capable of up-regulating inflammatory mediators in pancreatic acini and given that they are highly produced during AP, mainly may contribute to the inflammatory response triggered in acinar cells by fat necrosis. No role is played by Cl-FFAs generated as a result of neutrophil infiltration.  相似文献   

17.
Aquatic birnavirus induces necrotic cell death by an ill-understood process. Presently, we demonstrate that infectious pancreatic necrosis virus (IPNV) induces post-apoptotic necrotic cell death through loss of mitochondrial membrane potential (MMP) followed by caspase-3 activation in CHSE-214 cells. Progressive phosphatidylserine externalization was observed at 6 h post-infection (p.i.). This was followed by the development of bulb-like vesicles (bleb formation) at 8 h p.i. Progressive loss of MMP was also observed in IPNV-infected CHSE-214 cells beginning at 6 h p.i. At 8 h and 12 h p.i., IPNV-infected cells demonstrated a dramatic increase in MMP loss, rapid entry into necrotic cell death, and activation of caspase-9 and -3. Additionally, treatment with an inhibitor of MMP loss, bongkrekic acid, an adenine nucleotide translocase inhibitor, blocked IPNV-induced PS exposure and MMP loss, as well as reduced the activation of caspase-3. Taken together, our results suggest that IPNV induces apoptotic cell death via loss of MMP, thereby triggering secondary necrosis and caspases-3 activation. Furthermore, this death-signaling pathway is disrupted by bongkrekic acid in fish cells, indicating that this drug may serve to modulate IPNV-induced pathogenesis.  相似文献   

18.
Transmission electron microscopic study of Lithophyllum neoatalayense Masaki demonstrated that this alga used two mechanisms by which it sloughed cells from its surface. Epithallial filaments, produced by a layer of underlying initial cells, were two to four cells long. Terminal epithallial cells, those closest to the thallus surface, underwent senescence and shedding as previously described for other coralline algae. In addition, deep-layer sloughing occurred. During this process, which is known for only one other coralline alga, cell death occurred uniformly within a surface layer 40-50 μm thick. No pathogens or evidence of mechanical damage was detected. The zone of dead cells included the epithallial layer, the layer of initial cells, and some cortex cells beneath the initials. Pit plugs connecting living and dead cells at the edge of the necrotic zone were sealed by wall material deposited by the surviving cells, but cells within the necrotic zone showed no evidence of sealed pit plugs. The outermost surviving cells became new initial cells, which then divided to form new epithallial cells. Regeneration of the epithallial layer occurred before the thick layer of dead cells peeled away. The extensive deep shedding of both epithallial and initial cells in L. neoatalayense and the effectiveness of regeneration from cortex cells challenge the assumption that protection of initial cells is an important function of epithallial cells.  相似文献   

19.
AimsAlthough we previously demonstrated abdominal paracentesis drainage (APD) preceding percutaneous catheter drainage (PCD) as the central step for treating patients with moderately severe (MSAP) or severe acute pancreatitis (SAP), the predictors leading to PCD after APD have not been studied.MethodsConsecutive patients with MSAP or SAP were recruited between June 2011 and June 2013. As a step-up approach, all patients initially received medical management, later underwent ultrasound-guided APD before PCD, if necessary, followed by endoscopic necrosectomy through the path formed by PCD. APD primarily targeted fluid in the abdominal or pelvic cavities, whereas PCD aimed at (peri)pancreatic fluid.ResultsOf the 92 enrolled patients, 40 were managed with APD alone and 52 received PCD after APD (14 required necrosectomy after initial PCD). The overall mortality was 6.5%. Univariate analysis showed that among the 20 selected parameters, 13 factors significantly affected PCD intervention after APD. Multivariate analysis revealed that infected (peri)pancreatic collections (P = -0.001), maximum extent of necrosis of more than 30% of the pancreas (P = -0.024), size of the largest necrotic peri(pancreatic) collection (P = -0.007), and reduction of (peri)pancreatic fluid collections by <50% after APD (P = -0.008) were all independent predictors of PCD.ConclusionsInfected (peri)pancreatic collections, a largest necrotic peri(pancreatic) collection of more than 100 ml, and reduction of (peri)pancreatic fluid collections by <50% after APD could effectively predict the need for PCD in the early course of the disease.  相似文献   

20.
The process of penetration of a proteolytic enzyme applied to the surface of burn wound into the depth of necrotic tissue was considered. The model approximation describes three factors by a series of mathematical equations: inward-directed enzyme diffusion, counter-flow filtration of interstitial fluid (exudates), and irreversible inactivation of the enzyme by specific inhibitors present in exudates. According to the model, a quasi-stationary distribution of enzymatic activity through the thickness of the necrotic layer is achieved within 3 h and persists as long as the enzyme concentration on the wound surface is constant. The enzyme activity diminishes linearly from the wound surface to the mid-part of the necrotic layer. No enzyme activity is retained in the inner mid-part of the necrotic layer completely protected by the prevalent inhibitor. The ratio of enzyme concentration on the wound surface to inhibitor concentration in the interstitial fluid is the same as the ratio of the depth of active enzyme area to the depth of the inhibitor-protected area through the necrotic layer. The dynamics of accumulation of the active enzyme in the necrotic zone and the rate of enzyme inactivation in the wound by inhibitors were described by formulas applicable for practical purposes.  相似文献   

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