The effects of arginine and selective inducible nitric oxide synthase inhibitor on pathophysiology of sepsis in a CLP model

BACKGROUND: Sepsis is an arginine-deficient state and is associated with overproduction of nitric oxide (NO) by inducible nitric oxide synthase (iNOS). It has been indicated that low plasma levels of arginine are related to high mortality rates in sepsis. Arginine, however, is also known to be a precursor of NO. Therefore, administration of arginine in septic patients remains controversial. We examined the effects of co-administration of arginine and aminoguanidine, a selective iNOS inhibitor, on sepsis, using rat models. METHOD: Sepsis was induced in rats by cecal ligation and puncture (CLP). Effects of separate and combined administration of arginine and aminoguanidine were investigated by comparing plasma levels of arginine, expressions of heme oxygenase (HO)-1 and HO-2 in liver and lung, and nitrite + nitrate (NOx) excretion in urine, as well as neuroendocrine responses in urine in the early phase of sepsis. Seven-day survival rates were also examined. RESULTS: A combination of arginine and aminoguanidine recovered the plasma level of arginine at 6 h post-CLP, decreased expression of HO-1 in liver and lung at 24 h post-CLP, decreased urinary excretion of epinephrine, norepinephrine, dopamine, and 17-hydroxycorticosteroid in the first 24 h post-CLP, and increased 7-d survival. CONCLUSION: It is demonstrated that administration of arginine together with the selective iNOS inhibitor in the early phase of sepsis restores plasma arginine, reduces oxidative stress by probably maintaining NO derived from constitutive NOS, and attenuates neuroendocrine stress responses. This co-administration may be a beneficial treatment approach against sepsis.     

Implications of MYCN amplification in patients with stage 4 neuroblastoma who undergo intensive chemotherapy

Background/Purpose

This study aims to clarify the implications of MYCN amplification in patients with high-risk neuroblastomas treated with 2 different regimens of induction chemotherapy established by the Japan Study Group for Advanced Neuroblastoma.

Methods

Between 1985 and 2003 in Japan, 392 patients with stage 4 neuroblastomas who were older than 12 months were treated with 2 regimens of induction chemotherapy (the combination of cyclophosphamide [CTX], cisplatin [CDDP], pirarubicin, and vincristine or etoposide). Regimen 91A3 or 98A3 (A3) (CTX 2400 mg/m², CDDP 125 mg/m²) was a higher dose combination of CTX and CDDP than regimen 85A1 or 91A1 (A1) (CTX 1200 mg/m², CDDP 90 mg/m²). The 392 cases were classified into 3 groups (A, 1 copy; B, 2-9 copies; C, more than 10 copies) based on the MYCN amplification status by a Southern blot analysis.

Results

The 5-year overall survival rate (5-YS) was 41.1% for all 392 cases. Regarding the MYCN amplification status, the 5-YS was 46.6% for A group (n = 227), 22.7% for B group (n = 26), and 36.0% for C group (n = 139). A flouresence in situ hybridization analysis showed the presence of the cells with more than 10 copies in cases with 2 to 9 copies based on the Southern blot findings. Of the 227 patients in a group, the 5-YS was 46.7% for the 70 cases treated by A3 and 47.0% for 154 cases treated by A1 (nonsignificant). The 5-YS of the 210 patients with stem cell transplantation (SCT) (51.%) was significantly better than that of the 127 patients without SCT (41.1%) (P < .05).

Conclusions

Regarding the MYCN amplification status, the tumor aggressiveness might thus be different between 2 and 9 copies and a single copy of MYCN. In neuroblastomas with 2 and 9 copies of MYCN based on a Southern blot analysis, the MYCN amplification status should be analyzed using the flouresence in situ hybridization method. Induction chemotherapy followed by SCT according to the Japan Study Group for Advanced Neuroblastoma protocol improved the outcome of neuroblastomas with MYCN amplification; however, obtaining a further improvement in the long-term survival of stage 4 neuroblastomas may therefore require the development of an even more effective treatment modality.     

Intrahepatic biliary cysts in children with biliary atresia who have had a Kasai operation

Purpose

In patients with biliary atresia who had undergone a Kasai operation, treatment of intrahepatic biliary cysts (IBCs), particularly when complicated by cholangitis, is often difficult because the clinical implications and the course of IBCs are unclear. Thus, to determine the best treatment guideline, the morphology of IBCs, the clinical course, and the outcomes of such patients were evaluated.

Patients and Methods

A total of 44 patients with type III biliary atresia who underwent a Kasai operation from 1977 to 2005 were postoperatively examined for IBC by using ultrasonography and computed tomography. We classified the IBCs based on their number and shape.

Results

Intrahepatic biliary cysts developed in 12 of 54 patients. Three patients with solitary simple cysts and 1 patient with multiple simple cysts had no history of cholangitis. Two patients with multiple simple cysts had cholangitis at the time of IBC diagnosis and were treated with percutaneous transhepatic cholangiodrainage (PTCD). Patients with simple IBCs did not develop persistent cholangitis and their prognosis depended largely on their liver function; 3 of 6 patients remained healthy without cholangitis, whereas 3 patients required liver transplantation (LT) because of progressive liver failure or worsening hepatopulmonary syndrome, and not severe cholangitis. On the other hand, all 6 patients with multiple complicated IBCs had persistent cholangitis, eventually requiring LT. Even after bile flow to the intestine was reestablished after PTCD, both IBCs and cholangitis recurred. These patients required LT because of severe cholangitis.

Conclusions

Intrahepatic biliary cysts without cholangitis are not a source of infection and require no treatment. Simple IBCs with cholangitis can be controlled by antibiotics and/or PTCD. Patients with multiple complicated IBCs have a poor prognosis, requiring LT to control cholangitis. Although PTCD can control cholangitis in these patients as they wait for LT, PTCD does not alleviate it—LT is the final solution.     

Spontaneous closure of dural arteriovenous fistula after performing diagnostic angiography

The pathogenesis and clinical treatment of dural arteriovenous fistulas (DAVF) has been well established. However, only 15 cases of spontaneous closure of DAVFs have been reported. We describe a case of spontaneous closure of a DAVF. A 60-year-old male presented with pulsatile tinnitus. Selective cerebral angiography revealed a left posterior DAVF fed by the left occipital artery and the middle meningeal artery, which drained into the left transverse sinus and sigmoid sinus. Following the initial angiography, the patient exhibited vomiting with transient disorientation and amnesia. These symptoms, along with the tinnitus, disappeared by the following day. Seven days after the initial angiography, a second angiography was performed that revealed the complete disappearance of the DAVF. Previous reports have described a long period of closure for DAVFs following initial diagnosis. Possible mechanisms for spontaneous closure of DAVFs include the development of scar tissue or a sinus thrombosis that leads to occlusion of the DAVF In this case, the DAVF closure may have been due to a sinus thrombosis induced by sinus stenosis, since occlusion of the draining sinuses coincided with the spontaneous closure of the DAVF. In cases of non-traumatic DAVF without cortical venous reflex that do not present severe symptoms, a prudent course of treatment is necessary since there is a chance of spontaneous closure of the DAVF occuring.     

Huge retroperitoneal leiomyosarcoma: a case report

This is a case report of retroperitoneal leiomyosarcoma in a 61-year-old woman. She presented with a chief complaint of back pain. Computed tomography showed a left huge retroperitoneal tumor. The tumor was removed with left nephrectomy and left hemi-colectomy. Histological examination demonstrated leiomyosarcoma 26 x 20 x 16 cm in diameter and, 3.84 kg in weight. She died of local recurrence causing ileus 2 months after the surgery. Fifty-four cases of retroperitoneal leiomyosarcoma including the present case in the Japanese literature are reviewed.     

Successful Combination Therapy of Radical Liver Resection With 5-Fluorouracil/leucovorin,Oxaliplatin, Plus Bevacizumab for Ascending Colon Cancer With Pulmonary and 43 Liver Metastases: Report of a Case

At the time of diagnosis, 20% to 25% of patients with colorectal cancer already have liver metastases, the presence of which is a most important prognostic factor. A 64-year-old man was admitted to our hospital for investigation of anemia and multiple liver tumors. Examinations revealed ascending colon carcinoma with more than 40 liver metastases and 2 lung metastases. We performed right hemicolectomy with lymph node dissection, which was followed by 5-fluorouracil/leucovorin, oxaliplatin, plus bevacizumab (FOLFOX-BV). After 4 courses of chemotherapy, the lung metastases were in complete remission and the liver metastases had shrunk. We suggested the option of radical liver resection, but the patient declined initially as he had not suffered any severe side effects of FOLFOX-BV. After 23 courses of the chemotherapy, he agreed to undergo hepatectomy. We performed extended right lobectomy with partial left and caudal lobe resection. All of the macroscopic metastatic lesions were resected. Histopathologically, viable cancer cells were recognized in 7 of the 43 liver metastatic lesions. Postoperatively, FOLFOX-BV was restarted and continued for 10 months. At the time of writing, 15 months after the hepatectomy, the patient was well without evidence of recurrence of the cancer.     

Propofol-induced anesthesia in mice is mediated by gamma-aminobutyric acid-A and excitatory amino acid receptors

To elucidate the role of gamma-aminobutyric acid (GABA)(A) receptor complex and excitatory amino acid receptors (N-methyl-D-aspartate [NMDA] and non-NMDA receptors) in propofol-induced anesthesia, we examined behaviorally the effects of GABAergic and glutamatergic drugs on propofol anesthesia in mice. All drugs were administered intraperitoneally. General anesthetic potencies were evaluated using a righting reflex assay. The GABA(A) receptor agonist muscimol potentiated propofol (140 mg/kg; 50% effective dose for loss of righting reflex) induced anesthesia. Similarly, the benzodiazepine receptor agonist diazepam and the NMDA receptor antagonist MK-801 augmented propofol anesthesia, but the non-NMDA receptor antagonist CNQX did not. In contrast, the GABA(A) receptor antagonist bicuculline antagonized propofol (200 mg/kg; 95% effective dose for loss of righting reflex) induced anesthesia. However, neither the benzodiazepine receptor antagonist flumazenil, the GABA synthesis inhibitor L-allylglycine, nor the NMDA receptor agonist NMDA reversed propofol anesthesia. Conversely, the non-NMDA receptor agonist kainate enhanced propofol anesthesia. These results suggest that propofol-induced anesthesia is mediated, at least in part, by both GABA(A) and excitatory amino acid receptors. IMPLICATIONS: We examined behaviorally the effects of GABAergic and glutamatergic drugs on propofol-induced anesthesia in mice. The results suggest that propofol anesthesia is mediated, at least in part, by both GABA(A) and excitatory amino acid receptors.