Marked induction of gelatinases,especially type B,in host fibroblasts by human ovarian cancer cells in athymic mice

Two human ovarian adenocarcinoma cell lines, MCAS-3 and OVISE-3 were found to secrete little of any type of gelatinase in tissue culture. However, when these cell lines were implanted subcutaneously into nude mice the cyst fluids from the resultant tumors contained gelatinase A and/or B. The enzyme activities, especially of gelatinase B, were much higher in the malignant MCAS-3 tumors than in those of the less malignant OVISE-3 tumor cells. To elucidate the origin of gelatinase B in cyst fluids of the MCAS-3 tumors, murine skin fibroblasts (MSF) were isolated from a subcutaneous tumor in a nude mouse and tested for their proteinase secretion in culture. MSF cells, which secreted some gelatinase A and gelatinase B, were induced to secrete high levels of both enzymes, especially gelatinase B, by co-cultivation with MCAS-3 cells. In addition, gelatinase A activity was induced by incubation of MSF cells with the conditioned medium of either MCAS-3 or OVISE-3 cells, whereas gelatinase B was induced only with that of MCAS-3. Although cytokines or growth factors such as IL-1 TGF-1, TNF- or EGF stimulated the secretion of gelatinases A and B from MSF cells, their effects on gelatinase B activity were far less than that of the MCAS-3 conditioned medium. These results indicate that the major part of gelatinase B activity in the cyst fluids of the ovarian tumors is secreted by host interstitial cells stimulated by tumor-derived humoral factors. Similar tumor cell-host cell interactions may be important in the production of various proteinases in other tumor types.     

The in-vitro and in-vivo characterization of PLGA:L-PLA microspheres containing dexamethasone sodium phosphate

Dexamethasone sodium phosphate (DSP) is a widely used corticosteroid in the treatment of brain oedema associated with brain tumours. DSP has many side effects that limit its usage at an effective concentration. The objective of this study was to minimize these side effects by encapsulating DSP using biodegradable synthetic polymers, to extend the release time from microspheres and to evaluate the effectiveness in the treatment of brain oedema. Microspheres containing 5% DSP were formulated by the solvent evaporation method by using a 1:1 mixture of two synthetic polymers, poly(lactic-co-glycolic acid) and L-polylactic acid (PLGA and L-PLA). The surface morphologies and particle size distribution of the microspheres were investigated. The in-vitro     

Robotic intragastric surgery: A new surgical approach for the gastric lesion

Background

Intragastric surgery is accepted as a minimally invasive procedure for mucosal or submucosal lesions. Robotic surgery promises to extend the capabilities of the minimally invasive surgeon and many surgical specialties are applying this new technology. However, there is no report of robotic intragastric surgery. We describe the use of the da Vinci^® Surgical System for intraluminal mucosal resection of the stomach.

Methods

We developed our porcine intragastric surgery model using the Tuebingen MIS Trainer. We set a tentative lesion on the posterior wall near the esophagocardiac junction (ECJ) of the stomach and performed mucosal resection of the lesion using the da Vinci Surgical System. We also performed closure of the defect after mucosal resection and subsequent closure of the intentional gastric perforation.

Results

Using our porcine intragastric surgery model, we successfully performed mucosal resection of the tentative lesion. We also smoothly completed closure of the defect and closure of the perforation without any complications. The mean size of the mucosa was 6 cm and the mean duration of the procedure was only 12 min.

Conclusions

The safety and efficacy of robotic intragastric surgery was preliminarily established in this study. However, further studies are needed to prove its practical feasibility in humans using the da Vinci Surgical System to make it an effective operation.

     

Postoperative bronchial stump fistula responding well to occlusion with metallic coils and fibrin glue via a tracheostomy: a case report.

An 80-year-old man underwent middle and lower lobectomy of the right lung to treat squamous cell carcinoma (SCC) (4 cm in diameter) originating from the right B4 bronchus. On the 4th postoperative day, a massive air leak from the thoracic drain was noted. At that time, a diagnosis of bronchial stump fistula was made on the basis of the bronchoscopic findings. Continuous thoracic drainage, aspiration of sputum via a tracheostomy and intravenous administration of antibiotics were performed immediately after the diagnosis. However, the patient's condition was complicated by aspiration pneumonia. On the 11th postoperative day, bronchoscopic procedure to close the bronchial fistula was performed via the tracheostomy. During this procedure, metallic coils were first inserted into the fistula to serve as the core for occlusion. Then, instead of directly infusing fibrin glue, several small beans-sized pieces of Surgicell cotton (Johnson & Johnson Co., Cincinnati, OH) soaked in fluid A (concentrated fibrinogen) and the same number of Surgicell cotton pieces soaked in fluid B (thrombin) were alternately inserted into the fistula, to allow closure of the bronchial fistula. After this procedure, the embolus created remained in place without being expectorated, and the aspiration pneumonia entered remission, allowing the patient to be discharged from the hospital on the 24th postoperative day. At preset, 14 months after surgery, the patient is in good condition. This technique allows simple and reliable closure of a fistula if a tracheostomy is available. It should be selected as a therapy of first choice when dealing with patients with a postoperative bronchial stump fistula in poor general condition. Patients undergoing right pneumonectomy or middle and lower lobectomy of the right lung should be considered as belonging to a high risk group for bronchial fistula and as requiring preventable measures (e.g., covering the stump with an intercostal muscle flap).     

Intestinal ischemia induces late preconditioning against myocardial infarction: a role for inducible nitric oxide synthase

OBJECTIVE: We tested the hypothesis that occlusion of the superior mesenteric artery induces late preconditioning against myocardial infarction and examined the effects of pharmacological modifiers of inducible nitric oxide synthase activity on the late preconditioning in anesthetized rats. METHODS: Rats underwent an intestinal ischemia preconditioning protocol (30 min occlusion of the superior mesenteric artery) or were sham-operated. They were subjected to a sustained 30 min of coronary occlusion and 180 min of reperfusion 24 h later. RESULTS: In rats receiving no pharmacological intervention, the percentage of myocardial infarct within the area at risk and left ventricle was 72+/-4% and 31+/-2%, respectively, in sham-operated rats, and these were significantly reduced to 44+/-4% and 23+/-2% (P<0.01) 24 h after intestinal ischemia preconditioning. Myeloperoxidase activity was significantly reduced by intestinal ischemia preconditioning. Administration of aminoguanidine (300 mg/kg, s.c.) or S-methylisothiourea sulfate (3 mg/kg, i.v.), both relative inducible NO synthase inhibitors, 60 or 30 min before sustained myocardial ischemia not only abolished the late preconditioning afforded by intestinal ischemia, but also inhibited the ability of intestinal ischemia preconditioning to significantly reduce neutrophil infiltration. A change in inducible NO synthase activity was not observed in normal myocardium 24 h after intestinal ischemia, but 30 min of coronary occlusion significantly increased the inducible NO synthase activity in the preconditioned group, which was abolished by aminoguanidine or S-methylisothiourea sulfate. CONCLUSIONS: These data provide pharmacological evidence that induction of inducible nitric oxide synthase, following intestinal ischemia, is associated with increased myocardial tolerance to infarction 24 h later.     

Frequent co-localization of Cox-2 and laminin-5 gamma2 chain at the invasive front of early-stage lung adenocarcinomas

Laminin-5 is an extracellular matrix protein that plays a key role in cell migration and tumor invasion. Cox-2 is an induced isoform of cyclooxygenases that plays an important role in carcinogenesis, suppression of apoptosis, angiogenesis, and metastasis of colon cancer. We report frequent co-expression of cox-2 and laminin-5 at the invasive front of early-stage lung adenocarcinomas. We investigated the expression of cox-2 and laminin-5 immunohistochemically in 102 cases of small-sized lung adenocarcinoma (maximum dimension, 2 cm or less). Cox-2 and laminin-5 were expressed in 97 (95.1%) and 82 (80.4%) cases, respectively. Both were preferentially localized in cancer cells at the cancer-stroma interface, although cox-2 tended to show a diffuse staining pattern in some cases. A comparison of their staining patterns revealed a striking similarity in their distribution in 24 cases, and a partial overlap between their localization in another 20 cases. Moreover, an overall correlation was found between the expression levels of cox-2 and laminin-5 (P = 0.018). To gain insight into the mechanisms that regulate the expression of these proteins, we additionally studied their expression in 58 cases of stage I lung adenocarcinoma, in which p53 status was determined by immunohistochemistry, polymerase chain reaction-single strand conformation polymorphism analysis, and direct sequencing. The results showed that tumors with mutant p53 tended to express more cox-2 than those with wild-type p53 (P = 0.080). Also, tumors that overexpressed p53 had higher levels of cox-2 and laminin-5 than those without p53 overexpression (P = 0.032 and 0.047, respectively). Further immunohistochemical analysis showed that tumors that overexpressed both epidermal growth factor receptor (EGFR) and erbB-2 had higher levels of cox-2 and laminin-5 than those without concomitant overexpression of these proteins (P = 0.014 and P = 0.018, respectively). To see whether EGFR signaling is involved in cox-2 and laminin-5 expression, we further conducted in vitro analyses using six lung adenocarcinoma cell lines (A549, HLC-1, ABC-1, LC-2/ad, VMRC-LCD, and L27). Western blot analyses showed that cox-2 mRNA levels, and to a lesser extent laminin-5 gamma2 mRNA levels, correlated with the expression levels of erbB-2 and the phosphorylated form of MAPK/ERK-1/2 protein. The addition of transforming growth factor-alpha increased both cox-2 and laminin-5 gamma2 mRNA levels in A549, ABC-1, and L27 with different kinetics; the induction of cox-2 occurred earlier than that of laminin-5 gamma2. Finally, the migration of ABC-1 cells was inhibited by MAP kinase kinase inhibitor PD98059 and a selective cox-2 inhibitor NS-398. In contrast, the migration of A549 cells was inhibited by PD98059, but much less effectively by NS-398. These results suggest that co-stimulatory mechanisms may exist that increase the expression of cox-2 and laminin-5 at the invasive front of lung adenocarcinomas and that EGFR signaling could be one of the mechanisms. Further investigations are warranted concerning the role of cox-2 and laminin-5 in cancer cell invasion and the significance of p53 and EGFR signaling in the regulation of cox-2 and laminin-5 expression.     

Quantitative magnetic detection of finger movements in patients with Parkinson's disease

To develop a new measurement tool for quantitatively detecting the finger movement of a patient with Parkinson's disease (PD), we designed a magnetic sensing system consisting of a magnetic induction coil, a sensing coil, and a circuit unit. The sensing coil detects the inducted magnetic field that varies with the distance between the two coils, and the detected signals are demodulated in the circuit unit in order to obtain the variation voltage from the oscillation frequency. To obtain a coefficient for converting voltage to distance, we measured the output voltages for seven fixed finger positions of 12 normal volunteers. The voltage differences corresponding to the finger movement in 20 PD patients, six age-matched controls, and 12 normal volunteers were then recorded for 30s. To investigate the velocity and acceleration of the finger movement, we calculated their waveforms from the measured displacement waveform. We also detected the main frequency of the tapping rhythm by using a fast Fourier transform (FFT). The averaged amplitude of each waveform decreased with the disorder in the Hoehn-Yahr (HY) stage, while the averaged tapping frequency of PD patients did not have any correlation with this stage. It can be concluded that this magnetic sensing system can assess finger movement quantitatively.     

Relation between CD4+ T-cell activation and severity of chronic heart failure secondary to ischemic or idiopathic dilated cardiomyopathy

The percentage of CD4(+) T cells in blood is correlated with left ventricular dysfunction and decreased ejection fraction in heart disease. The aim of this study was to determine the relation between activation of CD4(+) T cells and New York Heart Association functional classes in chronic heart failure (HF) and differences in inflammatory activation between ischemic cardiomyopathy (IC) and idiopathic dilated cardiomyopathy (IDC). Blood samples were obtained from 47 patients with HF and 20 controls. Percentages of interferon-gamma-positive CD4(+) T cells (representative type 1 T-helper cells) and interleukin-4-positive CD4(+) T cells (representative type 2 T-helper cells) were analyzed using 3-color flow cytometry. The proportion of interferon-gamma-positive CD4(+) T cells was higher in patients with HF (28.96 +/- 12.90%) than in controls (18.12 +/- 5.28, p = 0.0006), but there was no difference in percentage of interleukin-4-positive CD4(+) T cells between the 2 groups. The proportion of interferon-gamma-positive CD4(+) T cells and plasma B-type natriuretic peptide levels increased with worsening of New York Heart Association functional class in the IC and IDC groups. The proportion of interferon-gamma-positive CD4(+) T cells in the IC group (33.88 +/- 13.33%) was higher than in the IDC group (22.33 +/- 8.88%, p = 0.002); however, plasma B-type natriuretic peptide levels were higher in the IDC group (358.0 pg/ml, 327.5 to 1,325.7) than in the IC group (82.7 pg/ml, 34.7 to 252.9, p = 0.019). In conclusion, we demonstrated pronounced type 1 T-helper cell activation in patients with HF in proportion to severity of HF and that the specificity of T-cell activation differs between patients with IC and those with IDC.