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Background: Pancreatodigestive tract anastomotic site stenosis is a problematic complication after pancreatoduodenectomy. Objective: We evaluated the feasibility and efficacy of endoscopic treatments for a stenotic pancreatodigestive tract anastomosis. Design: Retrospective study. Setting: Endoscopic units of a university-affiliated hospital and a general hospital. Patients: Fourteen patients with recurrent pancreatitis (n = 10) and pancreatic fluid fistula (n = 4) after anatomy-altering surgery with pancreatodigestive tract anastomosis. Interventions: The initial ERCP included obtaining a pancreatogram, introducing a 0.025-inch guidewire through the anastomosis, along which a 5F plastic stent or nasopancreatic drain was inserted. If initial ERCP failed, we attempted EUS-guided rendezvous, with a guidewire passed antegrade from the main pancreatic duct across the stenotic anastomosis. Main Outcome Measurements: Rates of successful intervention and clinical relief. Results: The initial intervention was successfully achieved in 6 of 14 patients (38%). Of the 6 patients with successful therapeutic endoscopies, 4 (66.7%) and 2 (25.0%) had undergone a previous pancreatogastrostomy or pancreatojejunostomy, respectively. Eight patients with an initial unsuccessful intervention successfully underwent a second intervention using an EUS-guided or US-guided rendezvous method. Finally, stenosis was relieved in all patients with either the retrograde placement of a pancreatic duct stent across the stenosis of an anastomotic site or antegrade percutaneous bougienage of the stenotic anastomosis. Limitations: Small sample size and lack of control patients. Conclusions: Endoscopic treatment of stenotic pancreatodigestive tract anastomosis for transanastomotic pancreatic juice drainage is safe and feasible. [ABSTRACT FROM AUTHOR]

BACKGROUND: Marked duodenal stenosis makes endoscopic biliary stenting (EBS) impossible, although it is the most common method for treating obstructive jaundice in patients with benign or malignant biliary strictures. Large-balloon dilation can be used to enable endoscope passage in the GI tract. OBJECTIVE: We describe 4 cases of successful EBS combined with the use of a large balloon for the treatment of difficult duodenal strictures in patients with benign and malignant biliary strictures. DESIGN: A retrospective case series. SETTING: Two tertiary referral centers. PATIENTS: Four patients: 1 with hilar carcinoma, 1 with gallbladder carcinoma, and 2 with chronic pancreatitis. INTERVENTIONS: After duodenal dilation, the slightly deflated balloon was pushed with the endoscope into the major papilla through the duodenal stricture (pushing method used in 2 patients). In the cases in which the major papilla was not accessible with the pushing method, a large dilation balloon was deflated completely after dilation, advanced beyond the stricture into the third portion of the duodenum, and reinflated to the maximum size. Pulling the dilation balloon catheter into the working channel while hooking the inflated balloon as the anchor at the anal side of the duodenal stricture, the endoscope was straightened to advance to the major papilla (hooking method used in 2 patients). MAIN OUTCOME MEASUREMENT: Successful EBS. RESULTS: Reaching the major papilla and EBS was accomplished in all 4 patients. LIMITATION: Small number of cases. CONCLUSIONS: Use of large-balloon dilation can contribute to successful ERCP in patients with difficult duodenal strictures. [ABSTRACT FROM AUTHOR]

Isolated characean internodal cells of Nitellopsis obtusa can be stored in artificial pond water for many days, but they cannot survive in 100mol m-3 NaCl solution unless more than several mol m-3 Ca2+ is added. Short-term effects of NaCl stress on the cytosolic concentration of Ca2+ ([Ca2+]c), cytosolic pH (pHc) and vacuolar pH (pHv) were studied in relation to the external concentration of Ca2+ ([Ca2+]c). Changes in [Ca2+]c were measured with light emission from a Ca2+-sensitive photoprotein, semisynthetic fch-aequorin which had been injected into the cytosol. Both pHc and pHv were measured with double-barrelled pH-sensitive microelectrodes. When internodal cells were treated with 100 mol m-3 NaCl (0-1 mol m-3 [Ca2+]0, [Ca2+]c. increased and then recovered to the original level within 60 rain. The time course of the transient change in [Ca2+]c was not influenced by the level of [Ca2+]c (0.1 and l0 mol m-3). In some cases, the transient increase in [Ca2+]c was induced only by increasing external osmotic pressure with sorbitol, in response to treatment with 100 mol m-3 NaCl (0.1 mol m-3 [Ca2+]c), pHc decreased by 0.1-0.2 units after 10 min but recovered after 30--60 min, while pHv increased by 0.4-0.5 units after 2-50 rain and tended to recover after 60 min. The initial changes in both PHc and pHv were suppressed when [Ca2+]c was raised from 0.1 to 10 mol m-3. These results show that the charophyte alga Nitellopsis call regulate [Ca2+]c, pHc and pHv under NaCl stress in the short term and that the protective effect of Ca2+ on salinity stress is apparently unrelated to perturbation of Ca2+ and pH homeostasis. [ABSTRACT FROM AUTHOR]

We constructed a new centrifuge microscope of the stroboscopic type, with which the cytoplasmic streaming in Nitella internodal cells under centrifugal acceleration was studied. Under moderate centrifugal acceleration (ca. 50-100× g), the direction of cytoplasmic streaming in an internodal cell of Nitella is parallel to the direction of the subcortical fibrils. The speed of endoplasm flowing contiguous to the subcortical fibrils is neither accelerated nor retarded by moderate centrifugal acceleration. The endoplasmic flow, however, stops suddenly following an electrical stimulus. The endoplasm contiguous to the subcortical fibrils is immobilized transiently at the time of streaming cessation induced by an electrical stimulus under centrifugal acceleration at 50-100× g, even at 900× g. It is suggested that transitory cross bridges between the immobilized endoplasm and the subcortical fibrils are formed at the time of streaming cessation. The bulk endoplasm flows as a whole in the direction parallel to that of the subcortical fibrils and stops promptly upon electrical stimulation. Soon after the stoppage the bulk endoplasm starts to flow passively in the direction parallel to that of the centrifugal acceleration as a result of the centrifugal force. [ABSTRACT FROM AUTHOR]

The behavior of cytoplasmic streaming in plasmodial strand of Physarum polycephalum was studied under centrifugal acceleration using a centrifuge microscope of the stroboscopic type. Cytoplasmic streaming in the plasmodium was greatly affected by changes in the acceleration. The endoplasmic flow in the centrifugal direction was accelerated, while that in the centripetal was retarded, by centrifugal acceleration. The centrifugal acceleration required to stop the endoplasmic flow in the centripetal direction did not cause total cessation of streaming but always induced a bidirectional flow of endoplasm in one and the same strand. Each profile of velocity distribution of the bidirectional flow was both parabola with flattened apex. One possible cause of the bidirectional flow is discussed. [ABSTRACT FROM AUTHOR]

By injuring cells of Valonia ventricosa, one of two survival strategies - wound-healing and protoplast formation - is induced. The present study revealed that turgor pressure, as well as Ca in bathing medium, is involved in the choice between these survival strategies. On the process of wound-healing, turgor pressure is recovered in the presence of both the wound plug, which closes the wound immediately after an injury, and the aggregation of protoplasm around the wound, which serves to protect the inflow of outer medium into the protoplasm layer and also to strengthen the wound plug. When the size of the wound is more than 150 μm in diameter, the protoplasmic aggregate strengthen the wound plug incompletely and, as a result, wound-healing is unsuccessful. In this case, the ejection of vacuolar sap is repeated, due to partial restoration of turgor pressure. In each ejection, the wound plug is blown off, together with the aggregated protoplasm and, after several ejections are repeated, the cell is unable to heal the wound because of a lack of protoplasm around the wound. Continuous depression of turgor pressure, during the repeat of the unsuccessful wound-healing, induces disorganization of the protoplasm layer. Under these conditions, the centrifugal propagation of protoplasmic aggregation, followed by the protoplasts formation, takes place easily. Effects of turgor pressure and Ca in the bathing medium upon the wound healing is discussed and the cytoplasmic behavior for survival of wounded cells is presented schematically. [ABSTRACT FROM AUTHOR]

Using a stroboscopic centrifuge microscope, we demonstrated that, when actin cables (=bundles of F-actin) had been previously removed locally from the cell cortex of Nitella internodes, the passively flowing endoplasm found there under centrifugal force did not stop at all upon electrical stimulus, while the actively flowing endoplasm contiguous to the actin cables at the normal cell cortex promptly stopped following the stimulus and was immobilized for several seconds. The results present evidence that, upon electrical stimulus, the presence of actin cables is required to immobilize the endoplasm flowing contiguous to the actin cables in a state that resists displacement by centrifugal force. [ABSTRACT FROM AUTHOR]