Clinical evaluation of allogeneic cultured dermal substitutes for intractable skin ulcers after tumor resection

Clinical research on allogeneic cultured dermal substitute (CDS), which was newly developed at the R&D Center for Artificial Skin of Kitasato University, has been carried out in medical centers across Japan with the support of the Millennium Project of the Ministry of Health, Labor and Welfare of Japan. Allogeneic CDS was prepared by cultivation of fibroblasts on a two-layered spongy matrix of hyaluronic acid and atelo-collagen. This paper reports the clinical results of application of allogeneic CDS in 12 patients with full-thickness skin defects after surgical resection of skin tumors. In 9 of 10 patients, healthy granulation tissue developed immediately, allowing us to perform split-thickness skin grafts at an early stage. In two cases, allogeneic CDS was used to cover an expanded mesh skin graft that had been applied to treat a large ulcer, and rapid epithelization was observed. No patient developed local infection nor local tumor recurrence after treatment with CDS. The spongy matrix itself as well as the vascular endothelial growth factor (VEGF) released by the allogeneic CDS seemed to be beneficial for the treatment of intractable skin ulcers. Allogeneic CDS functions as an excellent biological dressing, and could dramatically change the treatment of intractable skin ulcers.     

Osteoclastogenesis Inhibitory Factor/Osteoprotegerin Reduced Bone Loss Induced by Mechanical Unloading

Skeletal unloading resulting from space flight and prolonged immobilization causes bone loss. Such bone loss ostensibly results from a rapid increase in bone resorption and subsequent sustained reduction in bone formation, but this mechanism remains unclear. Osteoclastogenesis inhibitory factor/osteoprotegerin (OCIF/OPG) is a recently identified potent inhibitor of osteoclast formation. We studied effects of OPG administration on tail-suspended growing rats to explore the therapeutic potential of OPG in the treatment and prevention of bone loss during mechanical unloading, such as that which occurs during space flight. Treatment with OPG in tail suspension increased the total bone mineral content (BMC g) of the tibia and femur and the total bone mineral density (BMD g/cm²) of the tibia. Moreover, treatment with OPG prevented reduction not only of BMC and BMD, but also of bone strength occurring through femoral diaphysis. Treatment with OPG in tail-suspended rats improved BMC, BMD and bone strength to levels of normally loaded rats treated with vehicle. Treatment with OPG in normally loaded rats significantly decreased urinary excretion of deoxypyridinoline, but the effect of OPG in tail suspension was unclear. These results indicate that OPG may be useful in inhibiting bone loss-engendered mechanical unloading.     

Do multiple venous anastomoses reduce risk of thrombosis in free-flap transfer? Efficacy of dual anastomoses of separate venous systems

Whether or not multiple venous anastomoses reduce the risk of free-flap failure is a subject of controversy. We report here, for the first time, on the importance of selecting 2 separate venous systems of the flap for dual anastomoses. The efficacy of multiple anastomoses was verified through a retrospective review of 310 cases of the free radial forearm flap transfer. Dual anastomoses of separate venous systems (the superficial and the deep) showed a lower incidence of venous insufficiency than single anastomosis did (0.7% versus 7.5%; P < 0.05). On the other hand, dual anastomoses of a sole venous system showed no significant difference in the incidence of venous insufficiency compared with single anastomosis (11.5% versus 7.5%; P = 0.48). Our results suggest that dual venous anastomoses of separate venous systems is conducive to reduced risk of flap failure and affords protection against venous catastrophe through a self-compensating mechanism that obviates thrombosis of either anastomosis.     

Cytosolic phospholipase A(2) in hypoxic pulmonary vasoconstriction

Cytosolic phospholipase A(2) (cPLA(2)) releases arachidonic acid (AA) from phospholipids in cell membranes. To assess the role of cPLA(2) in hypoxic pulmonary vasoconstriction (HPV), we measured the increase in left lung pulmonary vascular resistance (LPVR) before and during hypoxia produced by left main stem bronchus occlusion (LMBO) in mice with and without a targeted deletion of the PLA2g4a gene that encodes cPLA(2alpha). LMBO increased LPVR in cPLA(2alpha)(+/+) mice but not in cPLA(2alpha)(-/-) mice. cPLA(2alpha)(+/+) mice were better able to maintain systemic oxygenation during LMBO than were cPLA(2alpha)(-/-) mice. Administration of a cPLA(2) inhibitor, arachidonyl trifluoromethyl ketone, blocked the LMBO-induced increase in LPVR in wild-type mice, while exogenous AA restored HPV in cPLA(2alpha)(-/-) mice. Intravenous angiotensin II infusion increased PVR similarly in cPLA(2alpha)(+/+) and cPLA(2alpha)(-/-) mice. Inhibitors of cyclooxygenase or nitric oxide synthase restored HPV in cPLA(2alpha)(-/-) mice. Breathing 10% oxygen for 3 weeks produced less right ventricular hypertrophy in cPLA(2alpha)(-/-) than in cPLA(2alpha)(+/+) mice, but restored HPV in cPLA(2alpha)(-/-) mice despite the continued absence of cPLA(2) activity. These results indicate that cPLA(2) contributes to the murine pulmonary vasoconstrictor response to hypoxia. Augmenting pulmonary vascular tone restores HPV in the absence of cPLA(2) activity.     

Novel Y283C mutation of the A subunit for coagulation factor XIII: molecular modelling predicts its impaired protein folding and dimer formation

In an Italian patient with severe factor XIII deficiency, a novel mutation, Y283C (TAT to TGT), was identified heterozygously by nucleotide sequencing analysis in exon VII of the gene for the A subunit. The presence of this mutation was confirmed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis in the proband and his brother. Molecular modelling predicts that the mutant molecule would be misfolded. It is probable that the impaired folding of the mutant Y283C A subunit led to its instability, which is at least in part responsible for the factor XIII deficiency of this patient.     

Brown-Séquard syndrome and cervical CSF leakage due to a knife injury: a case report

We report a case of Brown-Séquard syndrome and cervical CSF leakage caused by a knife injury. A 34-year-old man was involved in a fight and was stabbed on his occiput and back with a knife. Neurological examination on admission showed right hemiparesis, right hemihypesthesia and left hemihypalgesia, indicating Brown-Séquard syndrome. Furthermore, cerebrospinal fluid was leaking from the occipital stab wound. Head CT scan showed massive accumulation air in the subarachnoid space. Cervical MRI showed that the injury tract reached to the space between the occipital bone and the atlas. One week after admission, suboccipital craniectomy and duraplasty were performed because of continuous CSF leakage. Although, the CSF leakage recurred due to the wound infection, it disappeared naturally as the patient's general condition improved. Follow-up MRI studies demonstrated the cervical spinal lesion as hyperintensity on T2WI, which localized at the right side of the spinal cord. The patient's hemiparesis gradually improved and he underwent rehabilitation. Spinal cord injury due to a stab wound by a knife is rare in Japan. In this case, we suppose that the mechanism of spinal cord injury was due to direct injury by a knife avoiding the lateral corticospinal tract because his right hemiparesis obviously improved.     

Treatment and prognosis of primary thymic carcinoma

Forty consecutive cases with invasive ductal carcinoma of the breast (samples of both the primary invasive area and the involved node were available for 19 cases, multiple sections of breast tissue including both the primary invasive area and forefront intraductal cancerous area were available for 15 cases; and multiple sections of breast cancerous tissue and the involved node were available for six cases) were examined by immunohistochemical analysis for evaluation of their proliferation rate. In this study, we selected the PCNA index as a marker of the proliferation rate of the tumor cells. We demonstrated that the PCNA index of the primary invasive area was significantly higher than that of the forefront intraductal area (P – 0.0017), and the PCNA index of the involved nodes was significantly higher than that of the primary invasive area (P = 0.0004). These preliminary findings suggest that the progression from the tumor cells of the intraductal cancerous area to the metastatic tumor cells must be accompanied by two phases of increase in the proliferation rate. © 1993 Wiley-Liss, Inc.     

Utility of liposomes coated with polysaccharide bearing 1-amino-lactose as targeting chemotherapy for AH66 hepatoma cells

The cell recognition element is very important for drug delivery systems. We synthesized cholesteryl pullulan (CHP) bearing 1-aminolactose (1-AL) and introduced a saccharide, cholesteryl pullulan bearing 1-aminolactose (1-AL/CHP), to an outer layer of the conventional liposome as a cell recognition element. Lectin recognized the beta-galactose by aggregation of 1-AL/CHP coated liposome (1-AL/CHP liposome). The uptake of this liposome to AH66 rat hepatoma cells was greater than in liposomes without 1-aminolactose in vitro. Furthermore, 1-AL/CHP liposomal adriamycin showed a stronger antitumor effect in comparison with other types of liposomal adriamycin in vitro. When in vivo tumor-targeting efficacy was investigated in AH66 tumor transplanted mice using 3H-liposome, the tumor/serum radioactivity ratio in mice injected with 1-AL/CHP liposome was higher than that of mice injected with other liposomes. These observations suggest that 1-AL is effective as a cell recognition element. As a result, 1-AL/CHP liposome is considered to be a good carrier of anticancer drugs for the active targeting of tumor cells.