白花蛇舌草-半枝莲药对组分对结肠腺癌Lovo细胞生物学行为的影响

摘要:目的　探讨白花蛇舌草-半枝莲药对组分对结肠腺癌Lovo细胞增殖、侵袭、迁移和凋亡的影响及作用机制。方法　将白花蛇舌草、半枝莲按质量1∶1进行3次煎煮,获得水提物,后取适量浸膏用石油醚回流脱脂,再以乙酸乙酯进行多次萃取,获得白花蛇舌草-半枝莲药对组分,并计算得率。实验分为对照组（正常培养Lovo细胞）、白花蛇舌草-半枝莲药对组分低剂量组（10 mg/L）、中剂量组（30 mg/L）及高剂量组（50 mg/L）。通过噻唑蓝比色法（MTT）检测各组细胞培养24、48、72 h后的增殖抑制率。各组细胞培养48 h后,流式细胞仪检测细胞周期分布;Transwell实验检测细胞侵袭能力;划痕实验检测细胞迁移能力;TUNEL法检测细胞凋亡情况;Western blot法检测Grb2相关结合蛋白1（Gab1）、血管内皮生长因子受体2（VEGFR-2）、磷脂酰肌醇3-激酶（PI3K）、苏氨酸激酶（Akt）、基质金属蛋白酶-9（MMP-9）、B淋巴细胞瘤-2基因（Bcl-2）、Bcl-2相关X蛋白（Bax）蛋白表达情况。结果　化学萃取后的白花蛇舌草-半枝莲药对中主要含有对羟基苯乙酮、野黄芩苷、木犀草素和芹菜素4种化合物,组分得率为0.61%。与对照组相比,低、中、高剂量组细胞增殖抑制率升高,G1期肿瘤细胞比例增加,细胞凋亡指数增高,侵袭细胞数和划痕闭合率明显减小（均P＜0.05）,细胞中Gab1、VEGFR-2、PI3K、Akt、MMP-9、Bcl-2蛋白表达降低,Bax表达升高（均P＜0.05）,且存在剂量依赖性。结论　白花蛇舌草-半枝莲药对组分可抑制结肠腺癌Lovo细胞的增殖,降低其迁移和侵袭能力,诱导细胞凋亡,其机制可能与抑制Gab1/VEGFR-2/PI3K/Akt信号通路活化有关。     

The floating cardiac fat pad—sign of occult pneumothorax

Pneumothoraces are a possible sequela of chest trauma with potential morbidity and mortality if not recognized and treated promptly. A portable supine chest radiograph is frequently the first radiologic study performed in the setting of trauma. While large pneumothoraces can be readily recognized on these radiographs, smaller pneumothoraces are missed in up to 15 % of trauma patients. There are many radiographic signs of occult pneumothoraces, and we are presenting a new radiographic sign of occult pneumothorax. The floating cardiac fat pad sign occurs when pleural air collects anteriorly and superiorly in the most non-dependent portion of the chest lifting the pericardial fat pad off the diaphragm. Lung markings are still seen surrounding the pericardial fat pad due to the inflated lower lobe of the lung resting dependently. Rapid and accurate identification of pneumothoraces is critical but often difficult on chest radiographs. Although there are many existing radiographic signs for identification of pneumothorax, prospective identification of small pneumothoraces is still relatively poor. Here, we describe an additional sign which aides in the detection of pneumothoraces, the floating cardiac fat pad. When present, this should prompt further evaluation with chest CT or upright chest radiograph.     

Vestibular system may provide equivalent motor actions regardless of the number of body segments involved in the task

The vestibulospinal system likely plays an essential role in motor equivalence—the ability to reach the desired motor goal despite intentional or imposed changes in the number of body segments involved in the task. To test this hypothesis, we compared the ability of healthy subjects and patients with unilateral vestibular lesions (surgical acoustic neuroma resection 0.6 to 6.7 yr before the study) to maintain either the same hand position or the same trajectory of within arm reach movements while flexing the trunk, in the absence of vision. In randomly selected trials, the trunk motion was prevented by an electromagnetic device. Healthy subjects were able to preserve the hand position or trajectory by modifying the elbow and shoulder joint rotations in a condition-dependent way, at a minimal latency of about 60 ms after the trunk movement onset. In contrast, six of seven patients showed deficits in the compensatory angular modifications at least in one of two tasks so that 30–100% of the trunk displacement was not compensated and thus influenced the hand position or trajectory. Results suggest that vestibular influences evoked by the head motion during trunk flexion play a major role in maintaining the consistency of arm motor actions in external space despite changes in the number of body segments involved. Our findings also suggest that despite long-term plasticity in the vestibular system and related neural structures, unilateral vestibular lesion may reduce the capacity of the nervous system to achieve motor equivalence.     

Meta-analysis of retrojugular versus antejugular approach for carotid endarterectomy

Introduction

The retrojugular approach for carotid endarterectomy (CEA) has been reported to have the advantages of shorter operative time and ease of dissection, especially in high carotid lesions. Controversial opinion exists with regard to its safety and benefits over the conventional antejugular approach.

Methods

A systematic review of electronic information sources was conducted to identify studies comparing outcomes of CEA performed with the retrojugular and antejugular approach. Synthesis of summary statistics was undertaken and fixed or random effects models were applied to combine outcome data.

Findings

A total of 6 studies reporting on a total of 740 CEAs (retrojugular approach: 333 patients; antejugular approach: 407 patients) entered our meta-analysis models. The retrojugular approach was found to be associated with a higher incidence of laryngeal nerve damage (odds ratio [OR]: 3.21, 95% confidence interval [CI]: 1.46–7.07). No significant differences in the incidence of hypoglossal or accessory nerve damage were identified between the retrojugular and antejugular approach groups (OR: 1.09 and 11.51, 95% CI: 0.31–3.80 and 0.59–225.43). Cranial nerve damage persisting during the follow-up period was similar between the groups (OR: 2.96, 95% CI: 0.79–11.13). Perioperative stroke and mortality rates did not differ in patients treated with the retrojugular or antejugular approach (OR: 1.26 and 1.28, 95% CI: 0.31–5.21 and 0.25–6.50).

Conclusions

Currently, there is no conclusive evidence to favour one approach over the other. Proof from a well designed randomised trial would help determine the role and benefits of the retrojugular approach in CEA.     

Codon 12 ras mutations in patients with myelodysplastic syndrome: incidence and prognostic value

 To determine the prevalence of activated ras-oncogenes (N-ras, Harvey-ras Kirsten-ras), DNA derived from peripheral blood of 51 patients with myelodysplastic syndrome (MDS) was investigated. The method was based on the polymerase chain reaction (PCR) technique to amplify DNA, followed by restriction fragment length polymorphism (RFLP) analysis. Among the French-American-British (FAB) subtypes, N-ras mutations were found in two patients with refractory anemia with excess of blasts (RAEB), in one patient with refractory anemia with excess of blasts in transformation (RAEB-t), and in two patients with chronic myelomonocytic leukemia (CMML). MDS patients with a mutation at codon 12 of the N-ras gene showed shorter survival duration than other MDS patients of the same FAB subtypes, although these findings proved to be not statistically significant (P>0.1). Interestingly, all but one patient with N-ras mutation developed acute myelogenous leukemia (AML). In conclusion, the presence of mutation at codon 12 of the N-ras gene might serve as a negative prognostic factor at diagnosis of MDS. Received: 9 May 1996 / Accepted: 10 October 1996     

24-h blood glucose pattern in type I and type II diabetics after oral treatment with pentoxifylline as assessed by artificial endocrine pancreas

Summary Based on the known action of xanthine derivatives on the insulin secretion, the effect of pentoxifylline on carbohydrate homeostasis of type I (IDDM) and type II (NIDDM) diabetics was investigated. Pentoxifylline is known to exert a favorable influence on hemorheological disturbances in such patients. Twenty-four hour blood glucose pattern and insulin requirements were evaluated in type I and type II diabetics by the use of the artificial pancreas before and after a 14-day treatment with pentoxifylline 400 mg p.o. (Trental 400^?) t.i.d. During the stabilization period before treatment with pentoxifylline, NIDDM patients required 10.1±3.8 U of insulin and the IDDM 35±13.7 U. After 2 weeks on pentoxifylline, NIDDM required only 6.3±2.8 U (p<0.05) and IDDM 28.5±9.7 U (n.s.). Average blood glucose during the 24h decreased by 15.8±3.5% in NIDDM and by 10.3±2.5% in IDDM. Moreover, a significant smoothing of glucose fluctuations during the 24h was noted in both groups. It is concluded that pentoxifylline administered concurrently to any antidiabetic type of treatment leads to better blood glucose control as well as to prevention or delay of vascular complications. This work was supported by grants from the Social Ministry, Athens, Greece; Department of Internal Medicine I, University of Ulm, FRG;Deutsche Forschungsgemeinschaft SFB87 Endokrinologie, Ulm, FRG; the Alexander Onassis Foundation, Vaduz, Liechtenstein. Dedicated to Prof. Dr. med. h.c. Ernst F. Pfeiffer on the occasion of his 65th birthday anniversary.     

Effectiveness of acid suppression in preventing gastroesophageal reflux disease (GERD) after successful treatment of Helicobacter pylori infection

There is evidence that Helicobacter pylori eradication might predispose to gastroesophageal reflux disease (GERD). The aim of this prospective study was to examine the effectiveness of antisecretory treatment, after successful H. pylori eradication, in preventing GERD, since no data exist so far. Eighty initially H. pylori(+) patients, without GERD at the time of H. pylori eradication [50 peptic ulcer (PU) and 30 nonulcer (NU), 55 men, 25 women, median age 38 years, range 19–57], after successful H. pylori eradication were randomized to recieve either omeprazole 20 mg daily (group A) or no treatment (group B) for one year. All patients underwent upper gastrointestinal endoscopy at 0, 6, and 12 months or when GERD symptoms occurred. There were 40 patients in each group, and there were no statistically significant differences between the two groups in terms of sex, age, body weight, ulcer/no ulcer ratio, and other demographic data. Seven patients from group A and five patients from group B were lost to follow-up, and therefore there were 33 and 35 patients in groups A and B, respectively, who completed the study. One of 33 patients in group A (3%) and 10/35 (28.5%) in group B developed GERD symptoms during follow-up (P = 0.0022). The respective values for esophagitis were 0/33(0%) and 6/35(17.1%) (P = 0.0083). In conclusion, antisecretory treatment in H. pylori(+) patients, after successful eradication, is effective in preventing GERD.     

Granulocyte-macrophage colony-stimulating factor augmentation of T-cell receptor-dependent and T-cell receptor-independent thymocyte proliferation

The effects of granulocyte-macrophage colony-stimulating factor (GM- CSF) are not confined to cells of the myeloid lineage. GM-CSF has been shown to have effects on mature T cells and both mature and immature T- cell lines. We therefore examined the GM-CSF responsiveness of murine thymocytes to investigate whether GM-CSF also affected normal immature T lymphocytes. The studies presented here indicate that GM-CSF augments accessory cell (AC)-dependent T-cell receptor (TCR)-mediated proliferation of unseparated thymocyte populations. To identify the GM- CSF responsive cell type, thymic AC and T cells were examined for GM- CSF responsiveness. We found that GM-CSF augmentation of TCR-induced thymocyte proliferation appears to be mediated via augmentation of AC function, and not via direct effects on mature single-positive (SP) thymocytes. Enriched double-negative (DN) thymocytes were also tested for GM-CSF responsiveness. GM-CSF induced the proliferation of adult and fetal DN thymocytes in an AC-independent and TCR-independent single- cell assay. Thus, in contrast to the SP thymocytes, a DN thymocyte population was directly responsive to GM-CSF. GM-CSF therefore may play a direct role in the expansion of DN thymocytes and an indirect role in the expansion of SP thymocytes.