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991.
Alexandrium ostenfeldii is a widespread toxic dinoflagellate that has recently bloomed across the Adriatic Sea, seriously threatening both shellfish consumers and aquacultures. In 2007 we reported on preliminary studies carried out on field samples and cultures of A. ostenfeldii. At the time, along with three major spirolides – among which 27-hydroxy-13,19-didesmethyl spirolide C (3) proved to be a novel compound – a number of new minor spirolides were detected. Unfortunately, for all of them only Mass Spectrometry-based structural hypotheses could be ventured due to their very small amount. In the present paper we report on isolation and High Resolution Mass Spectrometry- and NMR-based structural elucidation of two of those minor spirolides detected in our previous study.  相似文献   
992.
993.
This retrospective study analyzes post-mortem examination data of 164 firearm-related casualties recorded by the Brescia, Italy Institute of Forensic Medicine between the years 1994 and 2006. The following variables were considered: year, month and day of death, gender and age of the victim, manner of death (homicide, suicide, accidental), type of weapon used, anatomical site and number of wounds, scene of death, and, whenever requested by the local District Attorney’s Office, results of the toxicological examinations conducted on the corpses of the deceased.In the County of Brescia, Italy, the 2006 firearm-related mortality rate amounted to 0.84 per 100,000 residents, with an average of 12.6 cases per year. The most common manner of death was suicide (60.4%), followed by homicide (35.9%) and accidental death (3.7%). Most victims were male, with an average age of 47.2 in cases of suicide, 37.9 in cases of homicide, and 47.5 in cases of accidental death. Considering all of the death manners contemplated in this study, the weapon types most frequently resorted to were single-action, short-barrelled guns, followed by multiple-action, long-barrelled ones. In cases of suicide, entry wounds were primarily situated on the head (right temple) and chest (precordium), while in cases of homicide no conclusions could be drawn as to the entry wounds’ predominant location.  相似文献   
994.
995.
Healing of diabetic wounds still remains a critical medical problem. Polydeoxyribonucleotide (PDRN), a compound having a mixture of deoxyribonucleotide polymers, stimulates the A2 purinergic receptor with no toxic or adverse effect. We studied the effects of PDRN in diabetes‐related healing defect using an incisional skin‐wound model produced on the back of female diabetic mice (db+/db+) and their normal littermates (db+/+m). Animals were treated daily for 12 days with PDRN (8 mg/kg/ip) or its vehicle (100 μL 0.9%NaCl). Mice were killed 3, 6, and 12 days after skin injury to measure vascular endothelial growth factor (VEGF) mRNA expression and protein synthesis, to assay angiogenesis and tissue remodeling through histological evaluation, and to study CD31, Angiopoietin‐1 and Transglutaminase‐II. Furthermore, we measured wound breaking strength at day 12. PDRN injection in diabetic mice resulted in an increased VEGF message (vehicle=1.0±0.2 n‐fold vs. β‐actin; PDRN=1.5±0.09 n‐fold vs. β‐actin) and protein wound content on day 6 (vehicle=0.3±0.07 pg/wound; PDRN=0.9±0.1 pg/wound). PDRN injection improved the impaired wound healing and increased the wound‐breaking strength in diabetic mice. PDRN also caused a marked increase in CD31 immunostaining and induced Transglutaminase‐II and Angiopoietin‐1 expression. Furthermore, the concomitant administration of 3,7‐dimethyl‐1‐propargilxanthine, a selective adenosine A2A receptor antagonist, abolished PDRN positive effects on healing. However, 3,7‐dimethyl‐1‐propargilxanthine alone did not affect wound healing in both diabetic mice and normal littermates. These results suggest that PDRN might be useful in wound disorders associated with diabetes.  相似文献   
996.
In the last few years serum CA 19-9 has been shown to be a highly sensitive marker of pancreatic adenocarcinoma. This study assesses the value of serum CA 19-9 assay in the postsurgical follow-up of patients undergoing pancreatic cancer resection. In 14 patients with cancer in the head of the pancreas and abnormal preoperative serum CA 19-9 values (greater than 40 U/ml), a pancreatoduodenectomy was performed. In all patients the CA 19-9 antigen was immunohistochemically demonstrated on the removed tumoral tissue. Postoperative serum CA 19-9 concentrations were serially measured 15 days after surgery and then every other month. Serum CA 19-9 scores returned to the normal range only in 7 (50%) of the resected patients. All patients with a normal postoperative value and none of those with a persistently elevated one survived longer than 7 months. Early postoperative serum CA 19-9 assay was superior to perioperative staging of the tumor as a prognostic index. All of the seven patients with postoperative normal values exhibited a subsequent increase within 16 months. In all cases the elevation of CA 19-9 occurred at least 2 months before ultrasound (US) could detect local recurrences of hepatic metastasis. Our data indicate that a normal early postoperative CA 19-9 score is a relatively favourable prognostic index in patients who undergo radical surgery for pancreatic cancer and that the CA 19-9 test can be used, as an early marker of recurrence, in monitoring these patients.  相似文献   
997.
998.
Transcatheter arterial chemoembolization (TAE) is generally considered to be an effective palliative treatment in patients with inoperable hepatocellular carcinoma (HCC). Recently, TAE has also been performed on operable cases, in order to reduce the chances of recurrence. This study was aimed at evaluating the histopathologic changes following chemoembolization in surgically resected HCCs. Chemoembolization was performed by selective intra-arterial injection of Lipiodol-chemotherapeutic agent (Adriamycin), followed by terminal embolization with Spongostan, in 5 patients with operable HCC. All patients underwent Computed Tomography (CT) follow-up and subsequent partial hepatectomy. CT after chemoembolization accurately demonstrated no increase in tumor size in all patients. In all HCCs a thick fibrous capsule was found. Histopathology of the surgically resected HCCs demonstrated complete necrosis of the primary tumor in 4/5 cases; 1 HCC remained viable and tumor cells were found in a few daughter nodules surrounding the tumor. In 1 case there were viable tumor emboli in the small portal vessels around the tumor. In patients with resectable HCC, TAE was useful in preventing tumor growth and in thickening the capsule, thus making surgery safer and reducing the chances of recurrence.  相似文献   
999.
Autoantibodies against double-stranded DNA (dsDNA) and nucleosomes represent a hallmark of systemic lupus erythematosus (SLE). However, the mechanisms involved in breaking the immunological tolerance against these poorly immunogenic nuclear components are not fully understood. Impaired phagocytosis of apoptotic cells with consecutive release of nuclear antigens may contribute to the immune pathogenesis. The architectural chromosomal protein and proinflammatory mediator high mobility group box protein 1 (HMGB1) is tightly attached to the chromatin of apoptotic cells. We demonstrate that HMGB1 remains bound to nucleosomes released from late apoptotic cells in vitro. HMGB1–nucleosome complexes were also detected in plasma from SLE patients. HMGB1-containing nucleosomes from apoptotic cells induced secretion of interleukin (IL) 1β, IL-6, IL-10, and tumor necrosis factor (TNF) α and expression of costimulatory molecules in macrophages and dendritic cells (DC), respectively. Neither HMGB1-free nucleosomes from viable cells nor nucleosomes from apoptotic cells lacking HMGB1 induced cytokine production or DC activation. HMGB1-containing nucleosomes from apoptotic cells induced anti-dsDNA and antihistone IgG responses in a Toll-like receptor (TLR) 2–dependent manner, whereas nucleosomes from living cells did not. In conclusion, HMGB1–nucleosome complexes activate antigen presenting cells and, thereby, may crucially contribute to the pathogenesis of SLE via breaking the immunological tolerance against nucleosomes/dsDNA.  相似文献   
1000.
Objectives: The benefits of combined chelation therapy with daily deferiprone (DFP) and subcutaneous desferrioxamine (DFO) have been widely reported in literature. We retrospectively evaluated the efficacy of different schedules of combined chelation therapy and the incidence of adverse events. Methods: We evaluated 36 patients affected by thalassemia major treated with combined chelation therapy. Patients were subdivided into four treatment arms according to severity of iron overload and previous onset of adverse events to DFP therapy: Group 1 (13 pts) DFP 75 mg/kg per d plus DFO (25–35 mg/kg per d for 5 d); Group 2 (6 pts) DFP 50 mg/kg per d plus DFO (25–35 mg/kg for 5 d), Group 3 (10 pts) DFP 75 mg/kg per d plus DFO (25–35 mg/kg for 3 d), and Group 4 (7 pts) DFP 50 mg/kg per d plus DFO (25–35 mg/kg for 3 d). Change in serum ferritin level was evaluated in all patients. Results: Overall, ferritin decreased from 2592 ± 1701 to 899 ± 833 ng/mL (P < 0.001). All treatments were able to reduce ferritin levels, but in patients of group 1 and group 2 the highest mean decrease in serum ferritin level and the greatest improvement in liver iron concentration (LIC) and in T2* values were observed. Conclusions: This study showed that the administration of DFO for 5 d a wk in combination with daily administration of DFP at 75 mg/Kg seemed to be the most efficacy and rapid method for reducing iron overload at liver and heart level. Furthermore, the use of different schedules of combined DFO and DFP administration was not associated with different incidence of adverse effects between the groups.  相似文献   
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