Significance of magnetic resonance imaging in acute head injury

One hundred seventy-seven patients who had incurred head trauma were studied with magnetic resonance imaging (MRI). Patients varied from those with mild injury without any focal neurological deficit to those with severe injury with post-traumatic coma. Altogether, 177 lesions were demonstrated by MRI in 123 of 177 patients within 3 days of injury using T2-weighted (SE2000/40,2000/111) and T1-weighted (IR1500/500/40) multislice sequences. In contrast, computerized tomography (CT) demonstrated 103 lesions in 90 patients. MRI was superior to CT in the diagnosis of nonhemorrhagic contusions demonstrated as a high-intensity area on T2-weighted imaging. MRI provided some information to evaluate the severity of diffuse axonal injury or to predict delayed traumatic intracerebral hematoma (DTICH).     

Spontaneous and isolated dissection of the main trunk of the superior mesenteric artery.

A 42-year-old man was admitted to another hospital complaining of acute abdominal pain that was induced by eating. Abdominal computed tomography and selective angiography revealed an intimal flap separating true and false lumens that was located 3 cm from the origin of the superior mesenteric artery (SMA). Emergency surgery was performed because of the sudden recurrence of diffuse abdominal pain after eating and abdominal aorta-SMA bypass grafting was done using a radial artery graft. Postoperative angiography revealed that the graft showed good patency. The postoperative course was uneventful and abdominal pain no longer occurred after eating. This excellent result was achieved by early diagnosis using CT scanning and angiography plus an aggressive surgical repair with a radial artery bypass graft for isolated dissection of the superior mesenteric artery.     

Conversion of pyridoxine into 6-hydroxypyridoxine by food components, especially ascorbic acid

In experiments designed to examine interactions between pyridoxine (PN) and food components, PN was found to be converted into an unidentified compound in the presence of the homogenates of various plant foods under mild conditions. The formation of the compound tended to be higher when food samples had a higher ascorbic acid (AsA) content. The reaction was neither thermal decomposition nor photodecomposition. This compound was also formed by incubating PN with AsA in the dark. Conversion of PN into the compound proceeded with oxidation of AsA, and was negligible under anaerobic conditions. The pH optimum for the reaction was between 4 and 7, and the temperature optimum was between 30 and 50 degrees C. The compound was purified by ion-exchange chromatography, isolated as colorless needles, and identified as 6-hydroxypyridoxine from UV, PMR, IR and MS spectral data. 6-Hydroxypyridoxine had neither vitamin B6 nor antivitamin B6 activity for Saccharomyces carlsbergensis 4228 (ATCC 9080). From these results, we inferred that hydroxylation of PN in the presence of food components, especially AsA, caused loss of vitamin B6 in plant foods during food processing, storage and cooking.     

Toxicity of cadmium oxide instilled into the rat lung. I. Metabolism of cadmium oxide in the lung and its effects on essential elements

The metabolism of cadmium oxide (CdO, insoluble form) and cadmium chloride (CdCl2, soluble form) instilled intratracheally into the rat lung was investigated. CdO might be solubilized rapidly in the lung and consequently pulmonary clearance rate of CdO was not so different from that of CdCl2. At a dose of 5 micrograms Cd/rat about 20% of the dose was translocated to the liver within 12 h, whereas gradual and consistent accumulation of Cd was observed in the kidney up to 7 days. Both pulmonary clearance and translocation of Cd to the liver were accelerated with the dose of instilled CdO, however, Cd accumulated in the kidney was proportional to the dose. Lung weight was increased by the instillation of CdO. Lung essential elements such as S, P, Mg, Zn and Mn were not affected in the inflammatory-reparative proliferative process, but Cu content of unit lung weight was slightly decreased.     

Investigation of the anti-complement agents, FUT-175 and K76COOH, in discordant xenotransplantation

Abstract: We examined whether hyperacute rejection (HAR) of a discordant xenograft in a nonhuman primate model could be inhibited by the anticomplement agents, FUT-175 (FUT) and K76COOH (K76). The inhibitory effect of FUT and K76 on baboon sera was studied in vitro by i) complement-mediated hemolysis of sheep erythrocytes (by measuring serum CH50) and ii) cytotoxicity to cultured pig kidney (PK15) cells. The in vivo administration of FUT (at 0.2–25 mg/kg/h i.v. continuously) and K76 (50 mg/kg i.v. bolus) allowed evaluation of the serum levels of these drugs. Both FUT and K76 inhibited serum CH50 in a concentration-dependent manner. An enhanced effect was obtained by combining K76 with FUT therapy. High concentrations of FUT (>10^-4 M) and K76 (>10³ μxg/ml) were necessary to suppress serum CH50 to <5% of the normal level. However, PK15 cytotoxicity remained at >50% in the presence of i) 10^-4 M of FUT, ii) 10³ μg/ml of K76, and iii) 10^-6 M of FUT + 10³ μg/ml of K76. Pig heart transplantation (HTX) was performed in two baboons receiving FUT (1 mg/kg/h i.v. continuously) and K76 (at 200 mg/kg ×1 or 400 mg/kg + 200 mg/kg × 2 i.v, respectively). Cytotoxicity of the serum to PK15 cells at the time of HTX showed 39% and 1% cell death, respectively, in these two baboons, and the CH50 level was 1% (of control level) and 0%, respectively. Graft survival was 4.5 hours and 10 hours (with death of the baboon), respectively (compared with a mean of 29 minutes in control experiments). Both excised grafts showed typical features of hyperacute rejection. Immunopathological studies revealed deposition of C1q, C3d, C6, properdin, and Factor B, demonstrating that complement activation was not fully inhibited by FUT and K76. We conclude that i) FUT and K76 are indeed potent complement inhibitors, ii) the dosages of FUT and K76 necessary to suppress complement-mediated injury cannot be extrapolated from previously reported data obtained from serum CH50 levels, and iii) higher (possibly toxic) dosages will be required to inhibit complement activation completely. It seems unlikely that HAR will be prevented by these drugs alone, although they may be beneficial when combined with other forms of therapy.     

Abdominal vagotomy attenuates interleukin-1β-induced nitric oxide release in the paraventricular nucleus region in conscious rats

Nitric oxide (NO) has recently been shown to modulate the hypothalamic–pituitary–adrenal axis response to interleukin-1β (IL-1β). We measured levels of nitrite (NO₂⁻) and nitrate (NO₃⁻) in the hypothalamic paraventricular nucleus (PVN) region using an in vivo brain microdialysis technique in conscious rats. Intraperitoneally administered IL-1β produced a significant increase in both NO₂⁻ and NO₃⁻ levels in the PVN region. We also examined the possible involvement of the abdominal vagal afferent nerves in this effect. In abdominal-vagotomized rats, the increase was significantly attenuated compared to that in sham-operated rats. Our results suggest that the abdominal vagal afferent nerves are involved in intraperitoneally administered IL-1β-induced NO release in the PVN region.     

A Possible Role of the Pineal Gland in Acute Immobilization-Related Suppression of Naloxone-Induced LH Release in Ovariectomized Estrogen-Primed Rats

It has been recently reported that acute immobilization stress almost completely suppresses the luteinizing hormone (LH) release induced by naloxone, a μ-opioid antagonist, in ovariectomized estrogen-primed rats. The present study examined the possible involvement of the pineal gland in the acute immobilization-related suppression of the naloxone-induced LH release. An intraventricular (ICV) injection of 15 μg naloxone produced an abrupt increase in circulating LH concentrations in non-stressed rats. The naloxone-induced LH release was completely eliminated when tested 60 min after the end of a 30 min session of acute immobilization. The same stress conditions did not affect LH-releasing hormone (LHRH)-induced LH release, suggesting that the stress-related suppression of the naloxone-induced LH release was a suprapituitary event. In chronically-pinealectomized rats, but not in sham-pinealectomized rats, naloxone injected 60 min after the end of the stress session evoked a significant increase in serum LH concentrations. However, naloxone injected ICV during the acute immobilization did not elicit LH release in either pinealectomized or sham-operated rats. Under non-stressed conditions, the LH secretory response to naloxone was similar in pinealectomized and sham-operated animals. The same stress (30 min immobilization) significantly increased pineal melatonin content as well as plasma melatonin concentrations in rats bearing intact pineal glands, indicating that stress actually affected the pineal function. These results provide evidence for a role of the pineal in the suppression of the LH response to naloxone after stress, but not during stress.     

Fibrolamellar hepatocellular carcinoma coexistent with a hepatocellular carcinoma of common type: Report of a case

A case of small fibrolamellar hepatocellular carcinoma (HCC) coexistent with a HCC of common type is herein reported. A 56-year-old man was diagnosed as having multi-nodular type HCC with liver cirrhosis. The serum alpha-fetoprotein (AFP) level was slightly increased. The patient underwent a partial caudate lobectomy and lateral segmentectomy. Histologically, both resected tumors were small HCCs measuring less than 2 cm in diameter. One was a fibrolamellar type located in the caudate lobe, while the other was the common type in the lateral segment of the liver. Positive immunohistochemical staining for AFP was observed in the tumor cells of the HCC of common type but was not observed in the fibrolamellar HCC. We also reviewed previously reported cases of fibrolamellar HCC in Japan, and discussed the clinicopathologic implications of this disease.