On the Relationship between Dynamic Contrast-Enhanced Ultrasound Parameters and the Underlying Vascular Architecture Extracted from Acoustic Angiography

Dynamic contrast-enhanced ultrasound (DCE-US) has been proposed as a powerful tool for cancer diagnosis by estimation of perfusion and dispersion parameters reflecting angiogenic vascular changes. This work was aimed at identifying which vascular features are reflected by the estimated perfusion and dispersion parameters through comparison with acoustic angiography (AA). AA is a high-resolution technique that allows quantification of vascular morphology. Three-dimensional AA and 2-D DCE-US bolus acquisitions were used to monitor the growth of fibrosarcoma tumors in nine rats. AA-derived vascular properties were analyzed along with DCE-US perfusion and dispersion to investigate the differences between tumor and control and their evolution in time. AA-derived microvascular density and DCE-US perfusion exhibited good agreement, confirmed by their spatial distributions. No vascular feature was correlated with dispersion. Yet, dispersion provided better cancer classification than perfusion. We therefore hypothesize that dispersion characterizes vessels that are smaller than those visible with AA.     

Achilles tendon overuse injuries.

Overuse injuries of the Achilles tendon are common in patients engaging in recreational athletics. Achilles tendon overuse injuries exist as a spectrum of diseases ranging from inflammation of the paratendinous tissue (paratenonitis), to structural degeneration of the tendon (tendinosis), and finally tendon rupture. Factors known to predispose patients to Achilles tendinitis include inadequate stretching, training errors, mechanical malalignment of the lower extremities, rigid training surfaces, and occasionally systemic disease. Treatment of the patient with paratenonitis and tendinosis is initially conservative, emphasizing passive stretching, concentric and eccentric strengthening, correction of training errors, and restoration of normal limb alignment. Patients resistant to this protocol often exhibit a more advanced degree of tendon change. A high percentage of these patients can benefit from surgical debridement of the involved tendon, and they can anticipate successful return to recreational athletics. Steroid injections should not be routinely used in patients with Achilles tendinitis. Rupture of the Achilles tendon following intratendinous injection has been reported.     

腹部外科常见感染性疾病的病原菌及药敏试验研究

为了了解本地区本医院腹部外科感染性疾病病原菌的构成比和药物敏感率的变化,指导临床用药,我们采用美国BD公司生产的6B和7D两种增菌瓶采集标本和培养细菌,并用该公司生产的生化板和药敏板,对1994～1996年269例常见的普外科感染性疾病患者的手术标本进行前瞻性的细菌培养和药敏试验研究.     

Copper vapor laser fragmentation of gallstones: in vitro measurements of wall heat transmission

Laser fragmentation is a promising new modality in management of retained CBD stones. Recent reports demonstrate the feasibility of lasers for this, but few studies have evaluated their safety (e.g., thermal injury may occur at greater than 43 degrees C). This study was conducted to measure heat transmission from lased bilirubinate and mixed stones to a simulated CBD wall. Four welded thermocouples were passed to the inside wall of 6-mm polyvinyl tubing 90 degrees apart to surround the lumen stone. The thermocouples were interfaced to a computer and temperatures were recorded every 270 msec. The tubing was submerged in a 37 degrees C water bath for all lasing work. A copper vapor laser (wavelength, 510 nm; 5.6 W; 5 kHz; pulse length, 30 ns) was attached to a 650-micron quartz fiber. A stone was "impacted" in the tubing and the laser fiber was pushed against the stone while making multiple passes to fragment it. Thirty mixed gallstones (mean size, 6.9 X 5.1 mm) and 20 bilirubinate gallstones (mean size, 7.1 X 5.2 mm) were fragmented during the study. Maximum temperature (Tmax), duration of Tmax (TmaxD), interval to stone piercing (TiP), and interval to fragmentation (TiF) were measured and comparisons were carried out with the SPSS statistical package using the t test procedure. The Tmax generated during fragmentation of bilirubinate stones (43.4 +/- 1.7 degrees C) was significantly less (P less than 0.002) than the Tmax for mixed stones (54.0 +/- 2.7 degrees C) but both Tmax values represented potentially injurious temperature levels.(ABSTRACT TRUNCATED AT 250 WORDS)     

Regulated expression of the IL-31 receptor in bronchial and alveolar epithelial cells, pulmonary fibroblasts, and pulmonary macrophages.

Interleukin-31 (IL-31), an IL-6 cytokine family member, is proposed to play a role in animal models of airway hyperreactivity. It is produced by activated T cells and signals via a heterodimeric receptor complex composed of IL-31Ralpha and OSMRbeta. Only low levels of IL-31Ralpha expression have been demonstrated in pulmonary epithelial cell lines, however, and little is known about the ability to regulate its expression and signaling. Therefore, primary cultures of human bronchial and alveolar epithelial cells, pulmonary fibroblasts, pulmonary macrophages, and established lines of immortalized bronchial epithelial cells (HBE) and alveolar carcinoma cells (A549) were analyzed by RT-PCR, immunoblotting, and thymidine incorporation. Distinct, cell type-specific regulation of IL-31Ralpha expression was detected. Transforming growth factor-beta (TGF-beta) enhanced IL-31Ralpha mRNA expression in primary cultures and established lines of epithelial cells, but not in macrophages. In contrast, interferon-gamma (IFN-gamma) induced IL-31Ralpha mRNA expression in macrophages. IL-31Ralpha protein expression was below detection threshold in primary epithelial cell cultures but was detectable in A549 cells and increased with TGF-beta treatment. In HBE and A549 cells, TGF-beta pretreatment increased IL-31-mediated Stat3 and extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation. In A549 cells, TGF-beta magnified IL-31-dependent suppression of proliferation. The data suggest that increased IL-31Ralpha expression correlates with an enhanced response to IL-31.     

Dissociation between syncytia formation and HIV spreading. Suppression of syncytia formation does not necessarily reflect inhibition of HIV infection

In this study, we have observed that a dissociation may occur in vitro between syncytia formation and HIV spreading. Efficient HIV spreading and virus replication occurred either in HIV-infected LFA-1+ lymphocytes treated with anti-LFA-1 mAb or in HIV-infected lymphocytes genetically deficient in LFA-1, despite the fact that syncytia formation was completely suppressed. Therefore, these results indicate that syncytia formation cannot be used as the sole parameter to evaluate the spread of HIV in vitro.     

Activated T-Lymphocytes Express Occludin, a Component of Tight Junctions

T-lymphocytes routinely traffic from the lymphoid and vascular compartments to the tissues during immune surveillance and inflammatory responses. This egress occurs without compromising endothelial barrier, which is maintained by tight junctions (zonula occludens). We report that T-lymphocytes up-regulate the expression of occludin, a major component of the tight junction in response to stimulation with phorbol ester (PMA) + calcium ionophore, CD3 antibody or T-cell receptor (TCR) antibody. Only activated T-lymphocytes express occludin; this adhesion molecule is nearly absent in resting T-lymphocytes. By immunofluorescence, occludin is seen in lymphocyte aggregates, but does not appear to mediate aggregation since only 50% of the cells in these clusters express occludin. Occludin is expressed between 8 and 24 h following stimulation, and persists for at least 48 h. These data indicate that activated T cells produce occludin which may regulate lymphocyte adhesion and trafficking.