Akihiro Ichinose

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.

Histopathological predictors of regional lymph node metastasis at the invasive front in early colorectal cancer

Akishima‐Fukasawa Y, Ishikawa Y, Akasaka Y, Uzuki M, Inomata N, Yokoo T, Ishii R, Shimokawa R, Mukai K, Kiguchi H, Suzuki K, Fujiwara M, Ogata K, Niino H, Sugiura H, Ichinose A, Kuroda Y, Kuroda D & Ishii T
(2011) Histopathology59, 470–481

Human adipose tissue-derived multilineage progenitor cells exposed to oxidative stress induce neurite outgrowth in PC12 cells through p38 MAPK signaling

BackgroundAdipose tissues contain populations of pluripotent mesenchymal stem cells that also secrete various cytokines and growth factors to support repair of damaged tissues. In this study, we examined the role of oxidative stress on human adipose-derived multilineage progenitor cells (hADMPCs) in neurite outgrowth in cells of the rat pheochromocytoma cell line (PC12).ResultsWe found that glutathione depletion in hADMPCs, caused by treatment with buthionine sulfoximine (BSO), resulted in the promotion of neurite outgrowth in PC12 cells through upregulation of bone morphogenetic protein 2 (BMP2) and fibroblast growth factor 2 (FGF2) transcription in, and secretion from, hADMPCs. Addition of N-acetylcysteine, a precursor of the intracellular antioxidant glutathione, suppressed the BSO-mediated upregulation of BMP2 and FGF2. Moreover, BSO treatment caused phosphorylation of p38 MAPK in hADMPCs. Inhibition of p38 MAPK was sufficient to suppress BMP2 and FGF2 expression, while this expression was significantly upregulated by overexpression of a constitutively active form of MKK6, which is an upstream molecule from p38 MAPK.ConclusionsOur results clearly suggest that glutathione depletion, followed by accumulation of reactive oxygen species, stimulates the activation of p38 MAPK and subsequent expression of BMP2 and FGF2 in hADMPCs. Thus, transplantation of hADMPCs into neurodegenerative lesions such as stroke and Parkinson’s disease, in which the transplanted hADMPCs are exposed to oxidative stress, can be the basis for simple and safe therapies.

Extended preseptal fat resection in Asian blepharoplasty.

The thickness of the upper eyelid is a bothersome condition that can be alleviated by blepharoplasty in Asians. Preseptal fat lies widely deep to the orbicularis oculi in the lower part of the upper eyelid, and the retro-orbicularis oculus fat (ROOF) pad lies in the lateral supraorbital area. We demonstrate the effectiveness of preseptal fat resection (PSFR) extended with ROOF resection in Asian patients. Three levels of PSFR were carried out in 258 eyelids of 129 Asian patients in conjunction with bilateral blepharoplasty: partial PSFR in 84 eyelids, total PSFR in 86, and extended PSFR that included ROOF resection in 68. The series revealed that PSFR was effective in reducing the thickness and heaviness of the eyelid, without major complications. PSFR including ROOF resection is an optional adjunct for Asian patients undergoing blepharoplasty. Nonetheless, the function of the grinding structures in the upper eyelid should be appropriately preserved.

Lateral Canthal Anatomy: A Review

The anatomy of the lateral canthus is analogous to that of the medial canthus, but with a less defined structure. Although the lateral canthal tendon occupies the major part of the lateral canthal anatomy, the lateral rectus capsulopalpebral fascia and other structures also play a significant role. Appropriate comprehension and consideration of the lateral canthal anatomy enable safe and effective performance in the lateral canthal surgeries. In this review, we present the lateral canthal anatomy along with updated topics. We discuss the lateral canthal tendon, lateral orbital thickening, lateral palpebral raphe, lateral canthal muscle, lateral rectus capsulopalpebral fascia, lateral check ligament, lateral retinaculum, and orbitomalar ligament.

Short-term postoperative flow changes after free radial forearm flap transfer: Possible cause of vascular occlusion

The risk for free flap thrombosis is greatly influenced by blood flow. Postoperative hemodynamic changes in vascular pedicles of the microvascular skin flap have not been reported, however. This study focuses on the intraoperative and postoperative changes in the flow volume in the vascular pedicles of the free forearm flap examined by color Doppler ultrasonography. The arterial flow volume increased continuously until day 7, compared with which, the volume after flap elevation was 36%. On day 1, it reached only 52%. In the venous pedicle, the flow volume through the cutaneous vein was only 37% compared with that through the radial vena comitans after flap elevation, whereas the volume through both veins was equal on day 7. Drastic changes in the flow explain the possible vascular occlusion during the early postoperative period in the free forearm flap transfer.

Role of Notch Signaling in the Maintenance of Human Mesenchymal Stem Cells Under Hypoxic Conditions

Human adipose tissue-derived multilineage progenitor cells (hADMPCs) are attractive for cell therapy and tissue engineering because of their multipotency and ease of isolation without serial ethical issues. However, their limited in vitro lifespan in culture systems hinders their therapeutic application. Some somatic stem cells, including hADMPCs, are known to be localized in hypoxic regions; thus, hypoxia may be beneficial for ex vivo culture of these stem cells. These cells exhibit a high level of glycolytic metabolism in the presence of high oxygen levels and further increase their glycolysis rate under hypoxia. However, the physiological role of glycolytic activation and its regulatory mechanisms are still incompletely understood. Here, we show that Notch signaling is required for glycolysis regulation under hypoxic conditions. Our results demonstrate that 5% O2 dramatically increased the glycolysis rate, improved the proliferation efficiency, prevented senescence, and maintained the multipotency of hADMPCs. Intriguingly, these effects were not mediated by hypoxia-inducible factor (HIF), but rather by the Notch signaling pathway. Five percent O2 significantly increased the level of activated Notch1 and expression of its downstream gene, HES1. Furthermore, 5% O2 markedly increased glucose consumption and lactate production of hADMPCs, which decreased back to normoxic levels on treatment with a γ-secretase inhibitor. We also found that HES1 was involved in induction of GLUT3, TPI, and PGK1 in addition to reduction of TIGAR and SCO2 expression. These results clearly suggest that Notch signaling regulates glycolysis under hypoxic conditions and, thus, likely affects the cell lifespan via glycolysis.

IMPORTANCE OF THE DEEP VEIN IN THE DRAINAGE OF A RADIAL FOREARM FLAP: A HAEMODYNAMIC STUDY

The free radial forearm flap has two drainage veins, the cutaneous and the deep, but no established consensus has been reached on the selection of the drainage pedicle. In our study, the flow volumes of the veins were examined by colour Doppler ultrasonography after 20 forearm flaps had been raised. The volume through the deep vein was significantly higher than that through the cutaneous vein (p < 0.01). In comparing the total flow (both veins open), the flow rate through the deep vein alone (cutaneous vein occluded) was over 80% in 13 cases, 60%̵1;80% in seven, and under 60% in none; that through the cutaneous vein alone (deep vein occluded) was 60%̵1;80% in eight, 40%̵1;60% in eight, under 40% in four, and over 80% in none. Our results show the importance of the deep vein, as indicated by its high drainage capacity from the early stages of flap transfer.

Comparison of surgical outcomes between simple posterior layer advancement of lower eyelid retractors and combination with a lateral tarsal strip procedure for involutional entropion in a Japanese population.

Aims To compare the effectiveness of simple posterior layer advancement of the lower eyelid retractor (LER) and combination surgery of posterior layer advancement of the LER with a lateral tarsal strip procedure for involutional lower eyelid entropion in a Japanese population. Methods 46 eyelids of 37 patients with horizontal laxity (Group A) and 47 eyelids of 42 patients without horizontal laxity (Group B) that underwent simple posterior layer advancement of the LER, and 47 eyelids of 37 patients with horizontal laxity that had the combination surgery (Group C) were retrospectively reviewed. Results All eyelids were judged as successfully corrected without recurrence in Groups B and C. On the other hand, although 42 eyelids (91.3%) were successfully altered in Group A, four eyelids (8.7%) showed recurrence at a mean period of 7.6 months postoperatively. Surgical success rates in Groups B and C tended to be higher than in Group A (p=0.056). Conclusions The combination surgery in Group C and simple posterior layer advancement of the LER in Group B provided complete surgical success. The present study suggests the importance of preoperative evaluation of horizontal laxity, allowing surgeons to perform the least amount of surgery to achieve success.

Transconjunctival Levator Aponeurotic Repair Without Resection of Müller’s Muscle

The number of patients with acquired ptosis is on the rise, and correction of blepharoptosis without any postsurgical scars on the eyelid is desired by most. Despite the advantages of the transconjunctival approach for blepharoptosis surgery, its use has been diminishing. The authors performed transconjunctival levator aponeurotic surgery without resecting Müller’s muscle for 21 eyelids in 14 patients with blepharoptosis. In 13 of these patients, 20 eyelids were successfully corrected. No major complications such as entropion, eyelid lag, or persistent irritation of the eye were observed. One eyelid with severe blepharoptosis showed an undercorrection of 1.5 mm. Aesthetic “double eyelid” with symmetric folds was achieved for all but one patient. The advantage is that without a skin incision, the reported method requires less downtime, leaves no conspicuous scar on the eyelid, and meets with marked satisfaction by most patients. It is beneficial for candidates who desire no skin incision but have indications for levator aponeurotic surgery and do not present with excessive upper eyelid laxity. This approach presents some challenges, however. One of these involves determining the degree of aponeurosis advancement according to the degree of the open eye during surgery and creating the desired “double-eyelid” shape and size, especially in Asians. Also, the surgeon needs to gain familiarity with the surgical anatomy of the everted eyelid. This method could, with refinements, become the procedure of choice for the correction of blepharoptosis in selected patients.