Jutamard Dokkaew, Sithiporn Agthong and Tanyawee Suantawee
Background: Nerve injury results in axonal degeneration and loss of sensory neurons in dorsal root ganglia (DRG). Enhanced oxidative stress was also observed following injury, suggesting potential efficacy of antioxidant therapy.
Objective: To examine the effects of vitamin E on nerve regeneration after nerve injury in rats.
Method: Unilateral sciatic nerve crush was performed on rats which were divided into three groups: control and 2 doses of vitamin E. The control group received only vehicle (corn oil) and vitamin E groups received α-tocopherol 500 and 1,000 mg/kg/day once daily by gavage. Regeneration was evaluated at 10 days post-injury. In a second experiment, there were two groups, vehicle and vitamin E 500 mg/kg/day, and the regeneration duration was extended to 3 weeks.
Result: The first experiment showed that vitamin E 500 and 1,000 mg/kg/day could significantly reduce DRG neuronal loss from 31.5% in the control group to 17.1% and 13.5%. However, the regeneration distances were not significantly different among groups. In the second experiment, although vitamin E 500 mg/kg/day significantly increased the plasma vitamin E level, motor recovery of the hind limb, as assessed by walking track analysis, was not significantly improved. By contrast, nerve morphometry revealed increased density and number of myelinated fiber after vitamin E treatment.
Conclusion: Vitamin E may be beneficial to sensory neuronal loss and nerve regeneration after nerve trauma
Natcha Nateniyom, Thanasil Huanmanop, Sithiporn Agthong and Vilai Chentanez
Knowledge of the anatomy of the celiac trunk (CT) and arterial supply of the hepatobiliary system is essential for surgical and interventional radiological treatment of upper abdominal diseases.
To determine the branching patterns of the CT and variation in origin and type of the right hepatic artery (RHA), left hepatic artery (LHA), and cystic artery (CA).
The anatomy of the CT in 100 cadavers from Thai adult donors was observed in 3 aspects: its branching pattern, the origin of the RHA and LHA, and the origin of the CA and its relation to the common bile duct (CBD) and common hepatic duct (CHD).
The majority of the CT branching pattern was categorized as the type II classical pattern, which has 3 branches: the left gastric artery (LGA), splenic artery (SA), and common hepatic artery (CHA). The RHA branched from proper hepatic artery in 67 cadavers. The origin of the accessory RHA was either from the abdominal aorta or superior mesenteric artery (SMA), whereas the replaced RHA originated from the CHA, SMA, or CT. The accessory LHA ramified from CHA (2 cases) and LGA (1 case). The replaced LHA was found in 30 cadavers and 29 arose from the CHA. The single and double types of CA were found in 94 and 4 cadavers, respectively. In all, 57% of single CA passed posteriorly and 39% passed anteriorly to the CBD and CHD.
To lower posttreatment complications, variations in the anatomy and the vascular supply of hepatobiliary structures should be considered.
Tulaporn Wongtawatchai, Sithiporn Agthong, Athitaya Kaewsema and Vilai Chentanez
Background: Peripheral neuropathy is a major side effect of cisplatin. Cisplatin preferentially accumulates in the dorsal root ganglia (DRG) and causes neuronal apoptosis. In vitro studies have implicated mitogenactivated protein kinases (MAPKs) in cisplatin-induced apoptosis. However, this has not been confirmed in vivo.
Objective: We studied the phosphorylation of MAPKs, ERK, JNK, and p38, in the DRG and sciatic nerve of rats treated with cisplatin, and correlated it with the neuropathic abnormalities.
Methods: Cisplatin 2 mg/kg was intraperitoneally injected in rats twice a week for five consecutive weeks. Neuropathy was assessed by measuring hind-paw thermal and mechanical thresholds, sciatic motor nerve conduction velocity (MNCV) and morphometric evaluation of DRG and sciatic nerve at various time points after the start of cisplatin treatment. Western blot analysis was done to determine the ratio of phosphorylated to total forms of MAPKs in the DRG and sciatic nerve.
Results: Cisplatin induced transient thermal hypoalgesia, late reduction in MNCV and histopathological abnormalities of DRG and sciatic nerve indicating the neuropathy. ERK was activated in the nerve and DRG in the eighth and twelfth weeks, respectively. Transient activation of JNK in the nerve and DRG was observed only in the first week. At the same time point to JNK, p38 was temporarily inhibited in the DRG. Late activation of ERK was correlated with the presence of pathological changes, suggesting the possible role of ERK in these abnormalities. No correlation between MAPKs and functional abnormalities was observed.
Conclusion: MAPK ERK might play a role in cisplatin-induced structural alterations in the DRG and sciatic nerve and can be the therapeutic target. However, to prove this hypothesis, future studies using the ERK inhibitor must be done.
Pimpimol Dangintawat, Jirun Apinun, Thanasil Huanmanop, Sithiporn Agthong, Prim Akkarawanit and Vilai Chentanez
Anatomic variation and supernumerary contents in the superior peroneal tunnel, and the prominence of the retrotrochlear eminence and peroneal tubercle are related to peroneal tendon disorders.
To investigate the prevalence, origin, and insertion of accessory peroneal muscles, the prominence of the retrotrochlear eminence and peroneal tubercle, and their association with peroneal tendon tears.
We examined 109 formalin-embalmed legs of cadavers from Thai donors. Accessory peroneal muscles and peroneal tendon tears were noted. Associations with peroneal tendon tears were evaluated using a χ2 test.
We found 48 accessory peroneal muscles comprising 13 peroneus quartus (PQ), 33 peroneus digiti quinti (PDQ), and 2 unusual muscles. All PDQ originated from the PB tendon and inserted on various parts of the 5th toe. The PQ originated mostly from the PB muscle belly and less from the tendinous part with various insertions on the retrotrochlear eminence, peroneal tubercle, cuboid, and dorsolateral surface of the 5th metatarsal base. Two unusual accessory muscles were identified, 1 coexisting with the PQ. A PB tendon tear was found in 13% of specimens. We found no association between the peroneal tendon tears and the accessory peroneal muscles, or prominence of the retrotrochlear eminence or peroneal tubercle.
The prevalence of PQ, PDQ, and unusual accessory peroneal muscles was concordant with previous findings. We noted a new type of unusual accessory peroneal muscle coexisting with the PQ. No association was found between peroneal tendon tears and the PQ, PDQ, or prominence of the retrotrochlear eminence or peroneal tubercle.