Complicated pancreatic abscesses: problems in interventional management

Twenty-five patients with grade D or E pancreatitis underwent percutaneous drainage. These patients required multiple computed tomography (CT) examinations, multiple catheter insertions, multiple catheter manipulations, and long-term catheter drainage. Eight of the 25 patients were successfully treated with catheter drainage alone. Sixteen underwent surgical drainage, ten after attempts at percutaneous drainage and six prior to radiologic drainage. Of the ten patients who had initial percutaneous drainage, only four were clinically improved from the drainage procedure alone. Although the fluid component of the abscess was often adequately drained in all ten patients, surgery was required to remove pieces of necrotic debris. Six patients who underwent surgical debridement had residual abscesses in the post-operative period and were all successfully treated with percutaneous drainage. One patient died from unrelated causes. Successful interventional management of patients with pancreatic abscesses requires intensive radiologic intervention and monitoring and may be better served by a combination of radiologic and surgical means.     

医学生心理健康状况与人格特征的相关分析

目的 :了解在校医学生的心理健康状况 ,为今后开展心理健教育提供有益的依据。方法 :采用 SCL-90和 EPQ量表对在校 5 88名医学生调查并作相关分析。结果 :医学生出现各类心理问题的比例为 6.80 %～ 3 2 .11% ,以强迫、人际敏感、抑郁和偏执为主。临医和护理专业学生心理问题的侧重点不同。女生在人际敏感、抑郁和恐怖等方面均高于男性。情绪稳定性 N和精神质 P与各因子及总均分呈正相关关系 (P<0 .0 1) ,掩饰度 L 与各因子呈显著负相关 (P<0 .0 1)。多因素回归分析表明 ,情绪稳定性 N和掩饰度 L对心理健康的影响起着重要作用。结论 :搞好学生的心理健康 ,加强健全人格教育是关键 ,同时要根据不同性别和专业区别地对待     

Mechanisms of control of the free Ca2+ concentration in the endoplasmic reticulum of mouse pancreatic β-cells: interplay with cell metabolism and [Ca2+]c and role of SERCA2b and SERCA3

OBJECTIVE

Sarco-endoplasmic reticulum Ca²⁺-ATPase 2b (SERCA2b) and SERCA3 pump Ca²⁺ in the endoplasmic reticulum (ER) of pancreatic β-cells. We studied their role in the control of the free ER Ca²⁺ concentration ([Ca²⁺]_ER) and the role of SERCA3 in the control of insulin secretion and ER stress.

RESEARCH DESIGN AND METHODS

β-Cell [Ca²⁺]_ER of SERCA3^+/+ and SERCA3^−/− mice was monitored with an adenovirus encoding the low Ca²⁺-affinity sensor D4 addressed to the ER (D4ER) under the control of the insulin promoter. Free cytosolic Ca²⁺ concentration ([Ca²⁺]_c) and [Ca²⁺]_ER were simultaneously recorded. Insulin secretion and mRNA levels of ER stress genes were studied.

RESULTS

Glucose elicited synchronized [Ca²⁺]_ER and [Ca²⁺]_c oscillations. [Ca²⁺]_ER oscillations were smaller in SERCA3^−/− than in SERCA3^+/+ β-cells. Stimulating cell metabolism with various [glucose] in the presence of diazoxide induced a similar dose-dependent [Ca²⁺]_ER rise in SERCA3^+/+ and SERCA3^−/− β-cells. In a Ca²⁺-free medium, glucose moderately raised [Ca²⁺]_ER from a highly buffered cytosolic Ca²⁺ pool. Increasing [Ca²⁺]_c with high [K] elicited a [Ca²⁺]_ER rise that was larger but more transient in SERCA3^+/+ than SERCA3^−/− β-cells because of the activation of a Ca²⁺ release from the ER in SERCA3^+/+ β-cells. Glucose-induced insulin release was larger in SERCA3^−/− than SERCA3^+/+ islets. SERCA3 ablation did not induce ER stress.

CONCLUSIONS

[Ca²⁺]_c and [Ca²⁺]_ER oscillate in phase in response to glucose. Upon [Ca²⁺]_c increase, Ca²⁺ is taken up by SERCA2b and SERCA3. Strong Ca²⁺ influx triggers a Ca²⁺ release from the ER that depends on SERCA3. SERCA3 deficiency neither impairs Ca²⁺ uptake by the ER upon cell metabolism acceleration and insulin release nor induces ER stress.Pancreatic β-cells stimulated by glucose display oscillations of the free cytosolic Ca²⁺ concentration ([Ca²⁺]_c) resulting from intermittent Ca²⁺ influx (1,2). Their endoplasmic reticulum (ER) takes up cytosolic Ca²⁺ by two sarco-endoplasmic reticulum Ca²⁺-ATPases (SERCAs): SERCA2b, ubiquitously expressed, and SERCA3, expressed only in islet β-cells (3,4). The role played by the ER in the [Ca²⁺]_c response to glucose is unclear. In particular, it has been suggested that Ca²⁺ influx through voltage-dependent Ca²⁺ channels facilitates the uptake of Ca²⁺ by the ER (5–10) or, on the contrary, triggers a release of Ca²⁺ from the ER (11–14), which might contribute to glucose-induced [Ca²⁺]_c oscillations (11,14) or to a sustained and pronounced [Ca²⁺]_c rise (12,13).The method of choice to monitor the free ER Ca²⁺ concentration ([Ca²⁺]_ER) in living cells uses genetically encoded, Ca²⁺-sensitive probes targeted to the organelle (15,16). One of them, D1ER, a ratiometric Ca²⁺ indicator, has been used in several cell types (17,18). However, the D1 Ca²⁺ sensor has a relatively high affinity for Ca²⁺ (60 µmol/L) (19). To yield a more suitable probe to monitor higher [Ca²⁺]_ER, we replaced D1 by D4 that has a lower affinity for Ca²⁺ (195 µmol/L) (20), and expressed it under the control of the insulin promoter in clusters of β-cells. In most experiments, [Ca²⁺]_ER (D4ER) and [Ca²⁺]_c (FuraPE3) were simultaneously recorded to evaluate the interplay between both parameters. Because SERCA2b and SERCA3 have been suggested to play distinct roles (4,5), we evaluated their respective roles on [Ca²⁺]_c and [Ca²⁺]_ER by using β-cells from wild-type (SERCA3^+/+, expressing SERCA2b and SERCA3) and SERCA3 knockout mice (SERCA3^−/−, expressing SERCA2b only) (21). We also assessed the role of SERCA3 in glucose tolerance, insulin secretion, and ER stress, as it was found that missense mutations of the human SERCA3 gene are associated with type 2 diabetes (22), SERCA3 expression is reduced in diabetic rat models (23), and SERCA3 is involved in ER stress (24).     

Evidence for a dual binding mode of dockerin modules to cohesins

The assembly of proteins that display complementary activities into macromolecular complexes is critical to cellular function. One such enzyme complex, of environmental significance, is the plant cell wall degrading apparatus of anaerobic bacteria, termed the cellulosome. The complex assembles through the interaction of enzyme-derived "type I dockerin" modules with the multiple "cohesin" modules of the scaffolding protein. Clostridium thermocellum type I dockerin modules contain a duplicated 22-residue sequence that comprises helix-1 and helix-3, respectively. The crystal structure of a C. thermocellum type I cohesin-dockerin complex showed that cohesin recognition was predominantly through helix-3 of the dockerin. The sequence duplication is reflected in near-perfect 2-fold structural symmetry, suggesting that both repeats could interact with cohesins by a common mechanism in wild-type (WT) proteins. Here, a helix-3 disrupted mutant dockerin is used to visualize the reverse binding in which the dockerin mutant is indeed rotated 180 degrees relative to the WT dockerin such that helix-1 now dominates recognition of its protein partner. The dual binding mode is predicted to impart significant plasticity into the orientation of the catalytic subunits within this supramolecular assembly, which reflects the challenges presented by the degradation of a heterogeneous, recalcitrant, insoluble substrate by a tethered macromolecular complex.     

Effects of laser therapy on experimental wound healing using oxidized regenerated cellulose hemostat

OBJECTIVE: The aim of this paper was to evaluate if the healing of wound sites containing oxidized regenerated cellulose hemostat can be optimized by laser therapy. BACKGROUND DATA: Topical hemostatic agents may be used to control bleeding in a variety of surgical sites. Hemostatic oxidized regenerated cellulose can cause strange body reactions and formation of granulomas. MATERIALS AND METHODS: Thirty-six male Wistar rats averaging 6 wk of age, weighing 250 g each, were anesthetized had a standard 0.5-cm(2) block of oxidized regenerated cellulose (Surgicel) inserted into an incision on the back of the tongue. Postoperatively the animals were randomly divided into two groups of 18 animals each: one was irradiated and one was not irradiated (control). In the treatment group, transmucosal laser therapy was applied in one area (Ga-Al-As laser, 4 J/cm(2), lambda = 685 nm, 35 mW, varphi = 0.06 mm) and consisted of four sessions, with one session carried out every 48 h. The animals were killed at three different times: G1 (1 d), G2 (3 d), and G3 (7 d). Tissues were stained with hematoxylin and eosin and then analyzed. RESULTS: It was observed that the treated group exhibited a greater reduction in edema and inflammatory infiltrate. CONCLUSIONS: These results suggest that laser therapy at 685 nm could improve the healing process, even when the inflammatory process has been stimulated by oxidized regenerated cellulose hemostat.