Experimental study of partial liquid ventilation in the setting of acute respiratory failure induced by sea water lung lavage in rabbits.

To study the effect of partial liquid ventilation (PLV) with perfluorocarbon on acute respiratory failure, 3 groups of 17 rabbits were examined to compare. After acute respiratory failure was induced by lung lavage with sea water in 12 of the 17 rabbits, 7 of the 12 rabbits were treated with conventional mechanical ventilation (AC group) and 5 of the 12 rabbits were treated with PLV using perfluorocarbon (AP group). The remaining 5 normal rabbits without acute respiratory failure were treated with PLV with perfluorocarbon as a control group (PL group). In the PL group, PaO2, PaCO2, blood pH, pulmonary compliance or pathological findings were not so changed after PLV. In the AC and AP groups, PaCO2 significantly increased, and in contrast, PaO2 and pulmonary compliance significantly decreased after lung lavage. However, these findings improved to almost the same levels as those of a control group within 2 h after the PLV treatment in the AP group, but in the AC group, these gradually deteriorated over time. As for the pathological findings, pulmonary vascular congestion, alveolar hemorrhage and inflammatory infiltration were observed in the AC group. However, these findings were not observed in the specimens of the AP group. From these results, PLV with perfluorocarbon was shown to be useful to improve gas exchange and pulmonary functions without major side effects.</p

Novel analgesics targeting brain-derived neurotrophic factor for neuropathic pain

　Brain-derived neurotrophic factor (BDNF) is necessary for the development, growth, and maintenance of nerve cells. BDNF is expressed in the dorsal root ganglion (DRG); binds to the Tropomyosin receptor kinasa B (TrkB) receptor, which has a tyrosine kinase domain, in the spinal cord; and plays an important role as a pain modulator. BDNF expression is increased in various types of pain, including acute pain, neuropathic pain, and cancer pain. Activation of the BDNF–TrkB pathway transmits pain information. In order to inhibit the BDNF–TrkB pathway, by sequestering BDNF, we constructed a cDNA expression plasmid encoding the extracellular region of rat TrkB fused to enhanced green fluorescent protein (EGFP). When the expression plasmid vector was administered to rat models of neuropathic pain, induced by spinal nerve ligation, statistically significant relief of pain was observed in terms of a 50% paw-withdrawal threshold using the von Frey test. The expression of TrkB-EGFP mRNA was detected in L5 lumbar vertebral nerves by quantitative reverse transcriptase polymerase chain reaction. To verify the pain-suppressive effect of the expression vector, truncated TrkB protein, without EGFP, was purified, and administered to pain model rats. A statistically significant suppressive effect of the truncated TrkB protein on neuropathic pain was observed 2 days after administration. The pain-suppressive effect of the truncated TrkB protein was more effective than that of the TrkB-Fc chimera protein and lasted longer than that of the TrkB antagonist ANA-12. Our results suggested that the truncated TrkB cDNA expression vector and truncated TrkB protein could be used as molecular targeted drugs in patients with neuropathic pain

Exogenous Basic Fibroblast Growth Factor and Nerve Growth Factor Enhance Sprouting of Acetylcholinesterase Positive Fibers in Denervated Rat Hippocampus

Basic fibroblast growth factor (bFGF) and nerve growth factor (NGF) were administered into the rat brain following unilateral fimbria-fornix transection. Both bFGF and NGF stimulated the sprouting of acetylcholinesterase (AChE) positive fibers in the hippocampus on the lesioned side. Furthermore, a small number of AChE-positive fibers were regenerated even when only the vehicle was administered. Rats treated with NGF as well as control group had only thin fibers, whereas those treated with bFGF had not only thin fibers but also thick fibers. These results indicate that intrinsic NGF is released and acts on damaged neurons directly, while bFGF acts them on directly and/or indirectly after brain injury.</p

Development of a novel analgesic for cancer pain targeting brain-derived neurotrophic factor

Brain-derived neurotrophic factor (BDNF) is necessary for nerve growth. BDNF is expressed in the dorsal root ganglion (DRG) and modulates pain transduction from peripheral nociceptors. TrkB, which is a BDNF receptor with a tyrosine kinase domain, acts as a pain modulator on the cell membrane of second neuron. If an exogenous truncated TrkB lacking a tyrosine kinase domain can competitively block the binding of BDNF to endogenous TrkB, inhibitory effects on pain are expected. We constructed two expression vectors coding truncated TrkB-GFP fusion proteins, lacking intracellular tyrosine kinase domain, with and without the transmembrane domain. By transfection of the vectors to HEK293 cells, the expression and localization of the modified receptor proteins were confirmed. The truncated TrkB with the transmembrane domain, TM (+), was localized on cell membrane surface of the transfected cells, and capable of BDNF binding on cell surface. TM (-) without the transmembrane domain was secreted from the transfected cells, and the secreted TrkB protein was confirmed the capability for binding with BDNF by pull-down assay. Furthermore, we developed a rat model of cancerous osteocopic pain for evaluating an analgesic effect of the modified TrkB vectors on cancer pain. Pain-related behavior, as assessed by von Frey tests, indicated hyperalgesia after cancer cell administration. BDNF expression was higher on the affected side of the DRG at the third lumbar vertebra L3 than on the unaffected side. When the modified TrkB vectors were administrated to the cancer pain model rats, both the TM (+) and TM (-) vector administration groups exhibited an analgesic effect. These results suggest that the modified TrkB receptors and their vectors are applicable as molecular targeted drugs for pain control in cancer patients

Partial purification and biological activities and properties of chick growth factors.

Cellular stimulating factors on cell proliferation in the supernatants of chick embryo carcases and adult muscles were studied. There were plural stimulating factors in embryonic and adult muscular supernatants that promoted cell proliferation without any supplement of sera and other materials. Salting-out methods with ammonium sulfate, ethanol fractionation, and isoelectric precipitation were used to isolate the stimulating factors, and these three methods proved the presence of plural stimulants on cell proliferation in the supernatants of chick embryo and adult muscles. The stimulants had altered physico-chemical properties and biological activities due to embryological development. The embryonic stimulants enhanced the synthesis of DNA and protein remarkably, and RNA synthesis in whole cell systems slightly. The muscular stimulants enhanced protein synthesis without any stimulation of DNA and RNA synthesis. Partial purification of the stimulants from the ethanol fractions was performed by DEAE-cellulose chromatography and Sephadex gel chromatography.</p

In Vivo Analysis of Extracellular Proteins in Rat Brains with a Newly Developed Intracerebral Microdialysis Probe

Peptides and proteins in the extracellular space in the central nervous system were investigated in vivo using an intracerebral microdialysis probe. The molecular cut-off of the hollow fiber which was used for the probe was approximately 100 kDa. We examined recovery rates of several compounds in vitro. The recovery rates of proteins and peptides were between 7-28%, with the exceptions of substance P and insulin-like growth factor I. The recovery rates of monoamines and their metabolites were 22-40%. In in vivo studies, two major proteins with apparent molecular weights of 62 kDa and 12 kDa, and several minor proteins (28 kDa, 43 kDa, 52 kDa and 70 kDa) were detected by SDS-polyacrylamide gel electrophoresis in the dialysate from a probe implanted in the striatum of anesthetized rats. These results suggest that the newly developed, intracerebral microdialysis probe might be useful for investigating the dynamic changes of peptides and proteins in the central nervous system.</p

Successful treatment of limited-stage small-cell lung cancer in the right mainstem bronchus by a combination of chemotherapy and argon plasma coagulation

The current standard-of-care treatment for patients with limited-stage small-cell lung cancer (SCLC) is concurrent chemoradiotherapy for local and systemic control. However, standard-of-care treatment strategies have not been established for those with limited-stage SCLC who have a history of thoracic radiotherapy due to concerns with complications associated with radiation overdose. A 37-year-old male developed an aspergilloma in the postoperative left thoracic space after he was treated with concurrent chemoradiotherapy for mediastinal type lung adenocarcionoma and subsequent left upper lobectomy for heterochronous dual adenocarcinoma. Fiberoptic bronchoscopy was performed to examine the status of the suspected bronchopleural fistula when a polypoid mass was observed in the right mainstem bronchus. A histological examination showed that the mass was SCLC at a clinical stage of cTisN0M0, stageIA, without local invasion. Since thoracic radiotherapy was not an option due to a previous history of thoracic irradiation, a combination treatment of carboplatin and etoposide was administered for 4 cycles and resulted in good partial response. In addition, argon plasma coagulation (APC) was performed as an alternative to curative radiotherapy on day 22 of the 4th cycle. The 5th cycle was administered 7 days after APC at which the anticancer therapy was completed. The patient remains disease-free 60 months after the completion of treatment, which suggests that this combination therapy may resolve very early-stage SCLC

Direct transbronchial administration of liposomal amphotericin B into a pulmonary aspergilloma

Pulmonary aspergillomas usually occur in pre-existing lung cavities exhibiting local immunodeficiency. As pulmonary aspergillomas only partially touch the walls of the cavities containing them, they rarely come into contact with the bloodstream, which makes it difficult for antifungal agents to reach them. Although surgical treatment is the optimal strategy for curing the condition, most patients also have pulmonary complications such as tuberculosis and pulmonary fibrosis, which makes this strategy difficult. A 72-year-old male patient complained of recurrent hemoptysis and dyspnea, and a chest X-ray and CT scan demonstrated the existence of a fungus ball in a pulmonary cavity exhibiting fibrosis. Although an examination of the patient's sputum was inconclusive, his increased 1-3-beta-D-glucan level and Aspergillus galactomannan antigen index were suggestive of pulmonary aspergilloma. Since the systemic administration of voriconazole for two months followed by itraconazole for one month was ineffective and surgical treatment was not possible due to the patient's poor respiratory function, liposomal amphotericin B was transbronchially administered directly into the aspergilloma. The patient underwent fiberoptic bronchoscopy, and a yellow fungus ball was observed in the cavity connecting to the right B2bi-beta, a biopsy sample of which was found to contain Aspergillus fumigatus. Nine transbronchial administrations of liposomal amphotericin B were conducted using a transbronchial aspiration cytology needle, which resulted in the aspergilloma disappearing by seven and a half months after the first treatment. This strategy could be suitable for aspergilloma patients with complications because it is safe and rarely causes further complications