Construction of an osteochondral-like tissue graft combining β-tricalcium phosphate block and scaffold-free mesenchymal stem cell sheet

Background

Aiming to construct an osteochondral-like structure, the combination of a β-tricalcium phosphate (βTCP) block with a scaffold-free sheet formed using mesenchymal stem cells (MSCs) was investigated.

Methods

Human bone marrow MSCs in a cell culture insert that was set in a 24-well plate were cultivated using a chondrogenic medium containing dexamethasone, IGF-1, and TGFβ3 for 3 weeks during which a cylindrical βTCP block was put on the sheet at day 1, and the cell sheet construct was harvested. In other experiments, at day 14, the construct was put on a cell sheet that was prepared the day before and cultivated for 3 weeks.

Results

The addition of a βTCP block resulted in a combined osteochondral-like construct and comparable staining intensity by Alcian blue, while the expression levels of the aggrecan and type II collagen genes decreased a little. During the culture with the βTCP block, the expression levels of the aggrecan gene increased monotonically. The increase in the inoculum cell number from 1.86 to 3.72 × 10⁶ cells resulted in marked increases in the thickness of cell sheet parts in the βTCP block and expression levels of the aggrecan and type II collagen genes, while the thickness of cell sheet parts on the βTCP block scarcely changed. On the other hand, the addition of a cell sheet that was prepared a day before to the construct at day 14 resulted in the marked increase in thickness of the cell sheet part on the βTCP block, while the thickness of that in the βTCP block did not increase.

Conclusion

A combined osteochondral-like structure was produced by putting a βTCP block on the sheet of MSC. The thickness of the cell sheet parts in and on the βTCP block could be increased by the increase in inoculum cell number and by providing an additional cell sheet, respectively.     

Effect of VA-045, a novel apovincaminic acid derivative,on closed head injury-induced neurological dysfunction in aged rats

Abstract

Objective: The strength–duration time constant (SDTC) is a measure of axonal excitability and it can provide information about Na⁺ channel function. In this study, we sought to examine the changes in the SDTCs of motor and sensory fibers of the median nerve in patients taking colchicine, which affects axoplasmic flow and may result in axonal neuropathy.

Methods and results: The SDTCs of motor and sensory fibers of 29 patients who had been taking colchicine were measured following stimulation of the right median nerve at the wrist. The results were compared with ten healthy age-matched subjects. No significant differences were found between the groups.

Conclusions: The lack of any effect on the SDTC by colchicine might have been due to the fact that axonal degeneration caused by colchicine affects the Na⁺–K⁺ ATP pump or that it affects internodal channels other than nodal channels.     

Randomized controlled trial of the LigaSure vessel sealing system versus conventional open gastrectomy for gastric cancer

Purpose

LigaSure, a bipolar electronic vessel sealing system, has become popular in abdominal surgery but few clinical studies have been conducted to evaluate its effectiveness in radical gastrectomy for gastric cancer.

Methods

In this multicenter, prospective, randomized controlled trial, patients with curative gastric cancer were randomly assigned to undergo gastrectomy either with LigaSure or a conventional technique.

Results

Of the 160 patients enrolled, 80 were randomized to the LigaSure group and 78 to the conventional group. Patient characteristics were well balanced in the two groups. There were no significant differences between the LigaSure and conventional groups in blood loss (288 vs. 260 ml, respectively; P = 0.748) or operative time (223 and 225 min, respectively; P = 0.368); nor in the incidence of surgical complications or duration of postoperative hospital stay. In a subgroup analysis of patients who underwent gastrectomy that preserved the distal part of the greater omentum, the use of LigaSure significantly reduced blood loss (179 vs. 245 ml; P = 0.033), and the duration of the operation (195 vs. 221 min; P = 0.039).

Conclusions

LigaSure did not contribute to reducing intraoperative blood loss, operative time, or other adverse surgical outcomes. The usefulness of the device may be limited to a specific part of the surgical procedure in open gastrectomy.     

Serotonin-1A receptor stimulation mediates effects of a metabotropic glutamate 2/3 receptor antagonist, 2S-2-amino-2-(1S,2S-2-carboxycycloprop-1-yl)-3-(xanth-9-yl)propanoic acid (LY341495), and an N-methyl-D-aspartate receptor antagonist,ketamine, in the novelty-suppressed feeding test

Rationale

α-Amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor stimulation has been proposed to be a common neural mechanism of metabotropic glutamate 2/3 (mGlu2/3) receptor antagonists and an N-methyl-D-aspartate receptor antagonist, ketamine, exerting antidepressant effects in animal models. AMPA receptor stimulation has also been shown to mediate an increase in the extracellular level of serotonin (5-HT) in the medial prefrontal cortex by an mGlu2/3 receptor antagonist in rats. However, involvement of the serotonergic system in the actions of mGlu2/3 receptor antagonists and ketamine is not well understood.

Objectives

We investigated involvement of the serotonergic system in the effects of an mGlu2/3 receptor antagonist, 2S-2-amino-2-(1S,2S-2-carboxycycloprop-1-yl)-3-(xanth-9-yl)propanoic acid (LY341495), and ketamine in a novelty-suppressed feeding (NSF) test in mice.

Results

The intraperitoneal administration of LY341495 or ketamine at 30 min prior to the test significantly shortened latency to feed, which was attenuated by an AMPA receptor antagonist, 2,3-dioxo-6-nitro-1,2,3,4-tetrahydr­obenzo[f]quinoxaline-7-sulfonamide (NBQX). The effects of LY341495 and ketamine were no longer observed in mice pretreated with a tryptophan hydroxylase inhibitor, para-chlorophenylalanine (PCPA). Moreover, the effects of LY341495 and ketamine were blocked by a 5-HT1A receptor antagonist, N-{2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl}-N-(2-pyridynyl) cyclohexane-carboxamide (WAY100635), but not by a 5-HT2A/2C receptor antagonist, ritanserin. Likewise, an AMPA receptor potentiator, 2,3-dihydro-1,4-benzodioxin-7-yl-(1-piperidyl)methanone (CX546), shortened latency to feed in the NSF test, which was prevented by depletion of 5-HT and blockade of 5-HT1A receptor.

Conclusions

These results suggest that AMPA receptor-dependent 5-HT release and subsequent 5-HT1A receptor stimulation may be involved in the actions of an mGlu2/3 receptor antagonist and ketamine in the NSF test.     

Carnitine is associated with fatigue following chemoradiotherapy for head and neck cancer

Conclusion: Longitudinal assessments of carnitine and fatigue in patients with head and neck squamous cell carcinoma suggest that cisplatin damages the carnitine system in patients undergoing chemoradiotherapy and that carnitine deficiency increases fatigue. Objectives: The purpose of this study was to monitor carnitine levels and fatigue in patients who received cisplatin-based CRT and, for comparison, in patients treated by surgery alone. Methods: To investigate the level of carnitine, mice were administered cisplatin. Next, a prospective analysis was performed to compare plasma carnitine levels before and after cisplatin-based chemoradiotherapy and to assess the relationship between carnitine levels and fatigue. Results: The plasma levels of total carnitine (TC), free carnitine (FC), and fatty acylcarnitine (AC) were significantly lower in mice receiving cisplatin compared with control mice. Mean total carnitine and free carnitine levels were significantly lower 2 weeks after chemoradiotherapy (total carnitine: Mean = 45.6, SD = 16.5, p = 0.01; free carnitine: Mean = 37.8, SD = 12.7, p = 0.02) than before chemoradiotherapy (total carnitine: Mean = 57.7, SD = 12.2; free carnitine: Mean = 48.1, SD = 11.6). There was a significant inverse correlation between carnitine levels and fatigue after chemoradiotherapy.     

Endoscopic removal of a fish bone foreign body in the hypopharynx with the modified Killian's method

Observing the entire circumference of the hypopharynx is usually difficult because most of the area is anatomically closed in the resting state. The modified Killian's method, consisting of a combination of the modified Killian position, head torsion, and the Valsalva maneuver, is a recently proposed procedure to improve the endoscopic view of the hypopharynx. A fish bone, which was invisible under regular endoscopy but was identified by CT, was successfully observed and removed under the modified Killian's method in a 71-year-old female. This method can be applied to diagnose and treat benign hypopharyngeal disease such as fish bone foreign body in addition to the detection of cancer.     

Amendment of the Japanese Consensus Guidelines for Autoimmune Pancreatitis, 2013 III. Treatment and prognosis of autoimmune pancreatitis

The standard treatment for autoimmune pancreatitis (AIP) is steroid therapy, although some patients improve spontaneously. Indications for steroid therapy in AIP patients are symptoms such as obstructive jaundice, abdominal pain, back pain, and the presence of symptomatic extrapancreatic lesions. Prior to steroid therapy, obstructive jaundice should be managed by biliary drainage, and blood glucose levels should be controlled in patients with diabetes mellitus. The recommended initial oral prednisolone dose for induction of remission is 0.6 mg/kg/day, which is administered for 2–4 weeks. The dose is then tapered by 5 mg every 1–2 weeks, based on changes in clinical manifestations, biochemical blood tests (such as liver enzymes and IgG or IgG4 levels), and repeated imaging findings (US, CT, MRCP, ERCP, etc.). The dose is tapered to a maintenance dose (2.5–5 mg/day) over a period of 2–3 months. Cessation of steroid therapy should be based on the disease activity in each case. Termination of maintenance therapy should be planned within 3 years in cases with radiological and serological improvement. Re-administration or dose-up of steroid is effective for treating AIP relapse. Application of immunomodulatory drugs is considered for AIP patients who prove resistant to steroid therapy. The prognosis of AIP appears to be good over the short-term with steroid therapy. The long-term outcome is less clear, as there are many unknown factors, such as relapse, pancreatic exocrine or endocrine dysfunction, and associated malignancy.