Oral immunization of mice with attenuated Salmonella typhimurium aroA expressing a recombinant Mycoplasma hyopneumoniae antigen (NrdF).

Mycoplasma hyopneumoniae is the etiological agent of porcine enzootic pneumonia, a commercially expensive respiratory disease of swine. Salmonella typhimurium SL3261 was used as a live carrier of plasmid pKF1, which encodes a 15-kDa recombinant M. hyopneumoniae protein. This expressed recombinant protein consists of the carboxy-terminal 11 kDa of a 42-kDa M. hyopneumoniae NrdF ribonucleotide reductase R2 subunit protein. Rabbit anti-15-kDa serum was able to inhibit the growth of viable M. hyopneumoniae J in vitro. When used as a live oral vaccine, S. typhimurium SL3261(pKF1) induced a significant secretory immunoglobulin A immune response in the lungs of mice orally immunized against the M. hyopneumoniae antigen. Utilization of live oral vaccines expressing potentially protective M. hyopneumoniae proteins, such as the NrdF antigen, which can stimulate a lung mucosal response against surface-accessible proteins may provide a cost-effective alternative to the present control strategies used for porcine enzootic pneumonia.     

Meniscal abnormalities: prospective correlation of double-contrast arthrography and arthroscopy

In a prospective study conducted over a 12-month period, 30 patients underwent double-contrast arthrography of the knee followed by arthroscopic study. An 80% correlation rate was found between results. Arthrography had a higher rate of accuracy (93%) than arthroscopy (84%) and had a 7% false-positive and 0% false-negative rate. A commonly overlooked arthrographic sign--the triple-S or stuck sail sign--was 91% accurate in the prediction of meniscal tears. The complementary nature of the two examinations is discussed.     

银杏叶提取物活血通络作用的药效学研究

目的：观察银杏叶提取物(EGb)的活血通络功效。方法：小鼠耳廓微循环实验、胶原蛋白-肾上腺素诱导的小鼠体内血栓形成实验、大鼠血液流变学实验及离体兔耳灌流实验。结果：银杏叶提取物经口给药．能显著改善小鼠耳廓微循环，抑制胶原蛋白-肾上腺素诱导的小鼠体内血栓形成，降低大鼠血液粘度，并能显著扩张离体兔耳血管。结论：银杏叶提取物有显著的活血化瘀功效。     

The effect of pre-vertebroplasty tumor ablation using laser-induced thermotherapy on biomechanical stability and cement fill in the metastatic spine

A biomechanical study comparing simulated lytic vertebral metastases treated with laser-induced thermotherapy (LITT) and vertebroplasty versus vertebroplasty alone. To investigate the effect of tumor ablation using LITT prior to vertebroplasty on biomechanical stability and cement fill patterns in a standardized model of spinal metastatic disease. Vertebroplasty in the metastatic spine is aimed at reducing pain, but is associated with risk of cement extravasation in up to 10%. Six pairs of fresh-frozen cadaveric thoracolumbar spinal motion segments were tested in axial compression intact, with simulated metastases and following percutaneous vertebroplasty with or without LITT. Canal narrowing under load, pattern of cement fill, load to failure, and LITT temperature and pressure generation were collected. In all LITT specimens, cement filled the defect without extravasation. The canal extravasation rate was 33% in specimens treated without LITT. LITT and vertebroplasty yielded a trend toward improved posterior wall stability (P = 0.095) as compared to vertebroplasty alone. Moderate rises in temperature and minimal pressure generation was seen during LITT. In this model, elimination of tumor by LITT, facilitates cement fill, enhances biomechanical stability and reduces the risk of cement extravasation.     

Coralline hydroxyapatite bone graft substitutes: preliminary report of radiographic evaluation

A new bone graft substitute made by conversion of the calcium carbonate exoskeleton of reef-building sea coral into hydroxyapatite has recently become clinically available. The normal radiographic appearance of two forms of this material is described. In the immediate postoperative period, the exoskeletal architecture of these implants is readily appreciated. With graft incorporation over the ensuing months, their intrinsic structure is gradually lost in association with poor marginal definition. Evolving radiographic findings reflect the biocompatible nature of these implants, which provides the potential for ingrowth of native bone with preservation of the coralline scaffold, resulting in enhanced biomechanical properties.     

Usefulness of contrast material in MR of patients with neurofibromatosis type 1.

PURPOSEOur objective was to determine the usefulness of routine administration of contrast material in brain MR imaging for the evaluation of areas of probable myelin vacuolization and neoplasms in patients with neurofibromatosis type 1 (NF-1).METHODSWe retrospectively reviewed 112 consecutive contrast-enhanced brain MR studies obtained over a period of 7 years in 109 symptomatic and asymptomatic patients compiled from two institutional NF-1 data bases. MR studies were analyzed for areas of probable myelin vacuolization, with attention to degree of enhancement and its impact on lesion detection and characterization. Usefulness of contrast material was graded as 0 = not useful, 1+ = somewhat useful, and 2+ = useful.RESULTSOf 112 studies, 45% (n = 49) were normal. In the remaining 63 studies, 88 regions of probable myelin vacuolization and 52 tumors were identified. Enhancement was not observed in any regions of probable myelin vacuolization. Enhancement was present in 31% of tumors, and, of these, was found to be useful in 44%, somewhat useful in 12%, and not useful in 44%. For enhancing tumors, contrast agent was useful for lesion detection in 19% and for lesion characterization in 25%.CONCLUSIONContrast administration is useful in baseline MR studies to maximize tumor detection and characterization, to add confidence to the diagnosis of benign probable myelin vacuolization, and to document stability of neoplasms on follow-up examinations.     

Anti-tumor effect of tumor necrosis factor and its induction of tumor variant of MBT-2 transitional cell carcinoma of the bladder

The effect of tumor necrosis factor (TNF), a potential anti-tumor agent, was assessed both in vivo and in vitro against MBT-2 transitional cell carcinoma of the bladder in C3H/HeHa mice. Systemic administration of either single or multiple doses of TNF into tumor bearing animals resulted in partial tumor regression and had a consistent but transient anti-tumor effect. Compared to control, untreated tumor bearing animals, TNF-treated tumor bearing mice had significantly smaller tumor volumes and slower tumor growth rates over the period of 12 days following TNF inoculation. No significant difference in tumor volumes and tumor growth rates between controls and TNF-inoculated mice was observed from day 12 to day 21 after TNF treatment. Assessment of TNF cytotoxicity against in vitro MBT-2 cell line using 3[H]-thymidine proliferation assay showed significant sensitivity of MBT-2 cells to treatment with TNF. A "Variant" MBT-2 cell line was derived by sequential culturing of the original MBT-2 cells in the presence of progressively higher concentrations of TNF in culture medium. Although the significant growth suppression on the MBT-2 tumor appears to be transient, further studies are warranted which may elucidate the immunologic and biologic behavior of TNF and this transplantable animal tumor.     

β-Methyl-15-p-iodophenylpentadecanoic acid metabolism and kinetics in the isolated rat heart

The use of 15-p-iodophenyl--methyl-pentadecanoic acid (Me-IPPA) as an indicator of long chain fatty acid (LCFA) utilization in nuclear medicine studies was evaluated in the isolated, perfused, working rat heart. Time courses of radioctivity (residue curves) were obtained following bolus injections of both Me-IPPA and its straight chain counterpart 15-p-iodophenyl-pentadecanoic acid (IPPA). IPPA kinetics clearly indicated flow independent impairment of fatty acid oxidation caused by the carnitine palmitoyltransferase I inhibitor 2[5(4-chlorophenyl)pentyl]oxirane-2-carboxylate (POCA). In contrast, Me-IPPA kinetics were insenstive to changes in fatty acid oxidation rate and net utilization of long chain fatty acid. Analysis of radiolabeled species in coronary effluent and heart homogenates showed the methylated fatty acid to be readily incorporated into complex lipids but a poor substrate for oxidation. POCA did not significatly alter metabolism of the tracer, suggesting that the tracer is poorly metabolized beyond Me-IPPA-CoA in the oxidative pathway.