Effect of splenectomy on hepatic metastasis of colon carcinoma and natural killer activity in the liver

We have previously demonstrated that administration of killed streptococcal preparation (OK432), a biological response modifier, increased the number of asialo GM₁-positive cells in the liver, enhanced NK activity of hepatic mononuclear cells, and reduced the number of hepatic metastases of colon 38 adenocarcinoma that were inoculated into the superior mesenteric vein of C57BL/6 strain mice. In the present study, to clarify the role of the spleen in immune surveillance of the liver, the effect of splenectomy on hepatic metastasis of colon carcinoma and on hepatic NK activity has been examined. The number of hepatic metastasis increased in the splenectomized mice, compared with that in sham-operated mice. Administration of OK432 increased the number of asialo GM₁-positive cells in the liver and enhanced NK activity of hepatic mononuclear cells in both groups, but NK activity of hepatic mononuclear cells in the splenectomized mice was less than that of the sham-operated mice. An enhanced NK activity of these cells was abolished by treatment with anti-asialo-GM₁ antibody plus complementin vitro. Interleukin-2 mRNA expression was increased in the spleen 2 hr after OK432 administration and persisted until 8 hr, but was scarcely noted in the liver. On the other hand, NK activity of hepatic mononuclear cells in the asialo GM₁-positive cell-depleted (previous administration of antiserum against asialo GM₁) mice was enhanced after OK432 administration in the sham operated and splenectomized mice, but an enhanced NK activity in these mice was only partially or not at all abolished by treatment with anti-asialo GM₁ antibody plus complementin vitro, respectively. These results suggest that the spleen could play an important role in an immune surveillance of the liver. In addition, OK432 first enhanced NK activity of hepatic mononuclear cells, which are sensitive to the antibody against asialo GM₁. However, when asialo GM₁-positive cells were depleted, OK432 enhanced NK activity of hepatic mononuclear cells, which are resistant to anti-asialo GM₁ serum.     

Optimal band imaging system can facilitate detection of changes in depressed-type early gastric cancer

BACKGROUND: The endoscopic diagnosis of depressed-type early gastric cancers is difficult because these cancers manifest as subtle changes in color and shape. The newly developed optimal band imaging (OBI) system can reconstruct the best spectral images derived from ordinary endoscopic images and enhances the mucosal surface without the use of dyes. This imaging technique is based on narrowing the bandwidth of conventional image arithmetically by using spectral estimation technology. OBJECTIVE: Evaluation of the usefulness of the OBI system for identifying the demarcation line of depressed-type early gastric cancers. DESIGN: Prospective study. SETTING: Jichi Medical University in Japan. PATIENTS: Twenty-seven cases with depressed-type early gastric cancer. MAIN OUTCOME MEASUREMENT: Comparative study for the success rate of identifying the demarcation line of depressed-type early gastric cancer by using optimal band images and conventional endoscopic images. RESULTS: Demarcation of the depressed-type early gastric cancer was easily identified by optimal band images without magnification in 26 of 27 cases (96%), because distinct demarcation was observed endoscopically between the reddish images of the cancerous lesion and the yellowish images of the surrounding noncancerous area. With 40-fold magnification of optimal band images, the demarcation was also clearly recognized in all cases. Medical students could point out the demarcation line with significantly greater accuracy by observing the new nonmagnified optimal band images than by the conventional images (P< .0001). LIMITATION: Small sample size. CONCLUSIONS: The new contrasting images of the OBI system can delineate the depressed-type early gastric cancer more easily than conventional endoscopy.     

An inverse correlation of VZV skin-test reaction,but not antibody,with severity of herpes zoster skin symptoms and zoster-associated pain

BackgroundCell-mediated immunity (CMI) has been considered to be related to the development of herpes zoster (HZ). However, there have been no large-scale prospective studies on the relationship between VZV-specific CMI and severity of HZ.ObjectiveWe carried out a large-scale prospective cohort study to clarify the relationship between immunological factors for varicella-zoster virus (VZV) and the clinical severity of HZ.MethodsWe carried out a cohort study on VZV immunity in a population living on an island cluster, Shozu County in Japan, and examined the people who developed HZ during a median follow-up period of 2 years, with a focus on the relationship between cell-mediated and humoral immunity and the severity of skin lesions and zoster-associated pain. A total of 12,522 people over the age of 50 were enrolled in this study, and 258 registrants were diagnosed as HZ. CMI was measured by VZV skin test, and humoral immunity was assessed with serological tests (neutralization test, immunoadherence hemagglutination test, and gpELISA test) for VZV-specific antibodies.ResultsCMI to VZV assessed by VZV skin test showed a significant inverse relationship to the severity of HZ skin lesions, and also to the severity of acute and subacute pain. Furthermore, weak response to the VZV skin test was associated with a high risk of post-herpetic neuralgia. In contrast, VZV-specific antibody titer was not associated with the severity of skin lesions and zoster-associated pain.ConclusionVZV-specific CMI, but not humoral immunity, may play a key role in controlling the severity of HZ skin lesions and zoster-associated pain.     

ENDOSCOPIC SUBMUCOSAL DISSECTION FOR SUPERFICIAL DUODENAL NEOPLASMS

Endoscopic submucosal dissection (ESD) has emerged as a novel technique for achieving en bloc resection for superficial neoplasms limited to the mucosa. ESD was originally developed in Japan as a method of endoscopic resection of superficial gastric cancers. In our hospital, ESD has been used concurrently in other parts of the gastrointestinal tract, including the esophagus and colorectum from the beginning of its development. However, ESD in the duodenum is considered more challenging than other parts. From August 2005 to March 2008, a total of 15 superficial duodenal neoplastic lesions in 14 patients were treated with endoscopic resection. Of these, nine underwent ESD. We report our experience with duodenal ESD with a combination of ST hood and hook knife.     

Ovarian cysts in precocious puberty

We describe a 7-year-old girl with precocious puberty in whom a single large cyst (5 cm) and several small cysts (8-10 mm) in the single remaining ovary were detected by the ultrasound examination. Endocrinological examinations confirmed the diagnosis of central precocious puberty. Pathologic findings after the removal of the cystic lesions revealed that the large cyst was derived from degenerated follicular cysts and the small cysts were identical to follicular cysts: all were considered to have been formed by gonadotropin stimulation. In general, surgical removal of an ovarian follicular cyst in central precocious puberty is inappropriate. However, in this unusual patient who had a degenerated large cyst, surgery seemed to be appropriate because of a previously removed teratoma in the contralateral ovary.     

Caspase-3 inhibitor rescues N -methyl- N -nitrosourea-induced retinal degeneration in Sprague-Dawley rats

The effect of a caspase-3 inhibitor on N -methyl- N -nitrosourea (MNU)-induced retinal degeneration was investigated. Sixty mg kg(-1)MNU was given intraperitoneally to 50 day old female Sprague-Dawley rats, and 4000 ng Ac-DEVD-CHO, a caspase-3 inhibitor, was injected intravitreally twice at 0 and 10 hr after MNU. In both peripheral and central retina, an apoptotic index of the photoreceptor cells 24 hr after MNU treatment was calculated by TUNEL labeling, and retinal damage 7 days after MNU treatment was evaluated from retinal thickness and a retinal damage ratio (length of damaged retina : whole retinal length). In MNU-treated rats, the TUNEL index 24 hr post-MNU was 79.5% in the peripheral and 83.7% in the central retina, while the Ac-DEVD-CHO injection significantly reduced it to 59.7 and 71.8%, respectively. Total retinal thickness 7 days after MNU was 38 microm in the peripheral and 75 microm in the central retina. Ac-DEVD-CHO injection increased these values to 72 and 77 microm, respectively. The retinal damage ratio 7 days after MNU was 98.5%. Ac-DEVD-CHO injection significantly reduced this value to 54.4%. The use of a caspase-3 inhibitor was effective in the suppression of MNU-induced retinal apoptosis and may be a therapeutic intervention in human retinitis pigmentosa.