Temporal and sequential changes of glial cells and cytokine expression during neuronal degeneration after transient global ischemia in rats.

BACKGROUND: How glial cells and cytokines are associated with the progression of delayed neuronal death induced by transient global ischemia is still unclear. To further clarify this point, we studied morphological changes in glial cells (microglial cells and astrocytes), and cytokine protein levels, during the progression of neuronal cell loss in CA1 (Cornu Ammonis 1) of the hippocampus after transient global ischemia. METHODS: Morphological changes in glial cells were studied immuno-histochemically. Nine cytokines (IL-1α, IL-1ß, IL-2, IL-4, IL-6, IL-10, GM-CSF, IFN-γ and TNF-α) were simultaneously measured by a multiplexed bead-based immunoassay from 6 h to day21 after transient four vessel occlusion (4VO) in rats. RESULTS: During the process of neuronal loss, we observed four distinct phases: (1) lag phase day0-2 (no NeuN+ cell loss observed), (2) exponential phase day2-7 (NeuN+ cells reduced in number exponentially), (3) deceleration phase day7-14 (reduction rate of NeuN+ cells became low), (4) stationary phase day14 onward (NeuN+ cell loss progressed no longer). In the lag phase, activated glial cells were observed in the entire hippocampus but later were gradually restricted to CA1. Cytokine protein levels in the lag and exponential phases were lower than in the deceleration and stationary phases. IL-1α, IL-1ß, IL-4, IL-6 and IFN-γ in 4VO were significantly higher in all four phases than in sham. Compared with sham level, GM-CSF was significantly high in the deceleration phase. TNF-α was significantly high in both the deceleration and stationary phases. CONCLUSION: Ischemic stress in 4VO activated glial cells in areas beyond CA1 in the lag phase. Pyramidal neurons were injured in CA1 from the end of the lag phase and then neuronal cells reduced in CA1 in the exponential phase. After neuronal death began, the influence of dead cells on glial cells and cytokine expression gradually became stronger than the influence by ischemic stress. Therefore, from the deceleration phase, changes in glial cells and cytokine production were likely caused by dead cells. Cytokine interaction in the microenvironment may determine the functions of IL-1α, IL-1ß, IL-4, IL-6 and IFN-γ in all four phases. The function of GM-CSF and TNF-α in the deceleration phase may be neurotrophic.

Assessment of secondary attack rate and effectiveness of antiviral prophylaxis among household contacts in an influenza A(H1N1)v outbreak in Kobe, Japan, May-June 2009.

This report describes the assessment of the secondary attack rate (SAR) and the effectiveness of post-exposure antiviral prophylaxis among household contacts in the first domestic outbreak of a novel influenza A(H1N1)v between mid-May and early June 2009 in Kobe city, Japan. Of the 293 subjects, 14 (4.8%) household contacts met the case definition and most secondary cases were probably infected around the time of symptom onset date of the respective index case. The SAR among household contacts who did not receive prophylaxis was 7.6%, similar to the rate of seasonal influenza, and the attack rate in siblings was significantly higher than that in parents. We conclude that it is important to establish routine infection control measures for households in order to prevent the spread of the virus among household contacts and, possibly, to the community. We could not conclude whether antiviral prophylaxis was effective or not. However, among close contacts with underlying disease who received prophylaxis, nobody developed a severe form of the disease.

Epidemiology of influenza A(H1N1)v virus infection in Japan, May-June 2009.

Between 9 May and 4 June 2009, a total of 401 laboratory-confirmed cases of influenza A(H1N1)v virus were reported in Japan, from 16 of the 47 Japanese prefectures. The two areas most affected were Osaka prefecture and Kobe city where outbreaks in high schools occurred leading to school closures. To date all cases have had symptoms consistent with seasonal influenza and no severe or fatal cases have been reported.

A role of mast cells for hepatic fibrosis in primary sclerosing cholangitis.

We encountered four patients with overt primary sclerosing cholangitis (PSC) which were histologically classified into stage 2 or 3. We examined the expression of stem cell factor (SCF), a ligand of c-kit, in injured bile ducts by immunohistochemistry, and mast cells were identified by immunohistochemistry using anti-HMCT (human mast cell tryptase) and anti-c-kit antibodies to clarify their relation with portal fibrosis coincident with destroyed bile ducts. SCF was detected in the epithelia of most bile ducts in PSC, and many HMCT- and c-kit-positive mast cells were found in portal tracts. Image analysis showed more significant numbers of c-kit-positive mast cells per area of portal tract in PSC than in chronic hepatitis C, and they might increase from stage 2 to 3. c-Kit-positive cells infiltrated into the portal tracts with SCF-positive destroyed bile ducts, and c-kit mast cells should be investigated in detail to make a role for portal fibrosis in PSC.

Elimination of Na+-dependent bile acid transporter from small intestine by ileum resection increases [correction of increase] colonic tumorigenesis in the rat fed deoxycholic acid.

Ileal Na+-dependent bile acid transporter (ISBT) constituting a gateway to enterohepatic circulation of bile acids occurs exclusively at the distal site of the small intestine. In the present study, we examined colonic tumorigenesis promoted by deoxycholic acid in relation to the expression of the ISBT. For this purpose, the small intestine of a Fischer-344 rat was resected a length of 20 cm above the ileo-cecal valve (ileal resection) or below the duodenum (jejunal resection). Then, rats were treated with an intraperitoneal injection of azoxymethane (15 mg/kg body wt.) once a week for 3 weeks and fed a 20% casein diet supplemented with 0.2% deoxycholate for 39 weeks. Northern blot analysis demonstrated that the ISBT mRNA was hardly detectable in ileum-resected rats. The excretion of fecal bile acids was 1.5-fold higher in the ileum-resected group than in the jejunum-resected group (P < 0.05). On the contrary, the serum bile acids concentration of ileal-resected rats was about one-half of that of jejunum-resected animals (P < 0.05). The tumor incidence and the total tumor number were significantly higher in the ileum-resected group than in the jejunum-resected one (P < 0.05). Interestingly, no tumor was found at the proximal colon in the jejunum-resected group while tumors developed frequently at the proximal site as well as mid and distal colon in the ileum-resected group. These observations demonstrate that malabsorption of bile acids owing to the lack of ISBT enhanced colon tumorigenesis.

Cell proliferation and cell loss in intramucosal signet ring cell carcinoma of canine stomachs induced by N-ethyl-N'-nitro-N-nitrosoguanidine.

Signet ring cell carcinoma was induced in canine stomachs by N-ethyl-N'-nitro-N-nitrosoguanidine, and modes of cell proliferation and turnover in the carcinoma were studied by 3H-thymidine autoradiography in conjunction with morphometric analysis. From 2 to 15 months after the cessation of 8 months carcinogen treatment, carcinomas in an early stage were obtained. Most of the cancer tissues confined to the lamina propria showed a layered structure. This comprised three layers; the superficial and the deep layer were composed of signet ring cells, and the middle layer was composed of small round cells. The dogs were labeled with 3H-thymidine by s.c. injection and by local infusion of the celiac artery. Flash-labeled autoradiographs revealed that most 3H-thymidine incorporating cancer cells were located around the middle layer, with a small amount of mucin. Using a pulse labeling experiment, those labeled carcinoma cells were shown to migrate from the middle layer towards the surface. Morphometric analysis of the autoradiographs showed that the small cells in the middle layer migrated upwards and produced mucin to become full-blown signet ring cells by 5.5 days. In 15 days, most labeled cancer cells in the superficial layer had disappeared. This mode of cellular turnover appeared to mimic a cell renewal system of the normal gastric mucosa. If the cancer cells turn over in this way, the tumor must grow slowly, remaining as an intramucosal cancer for a relatively long period.

Morphology and modes of cell proliferation in earliest signet-ring-cell carcinomas induced in canine stomachs by N-ethyl-N'-nitro-N-nitrosoguanidine.

Signet-ring-cell carcinomas were induced in the stomach of 12 beagle dogs by p.o. administration of N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG), and the morphology and modes of cell proliferation in an incipient stage of cancer growth were studied with bromodeoxyuridine (BrdUrd) incorporation. From 5 to 27 months after the completion of 8 months' carcinogen treatment, minute carcinomas were found in the stomachs of 9 dogs. Before sacrifice, the dogs were given a single or repeated i.v. injections of BrdUrd for 1-3 days. Minute signet-ring-cell carcinomas were found to form a layered structure, in which the cancer cells proliferated in the lamina propria at the gland-neck level and differentiated to postmitotic signet-ring cells at the upper and lower levels of the mucosa. From repeated injections of BrdUrd, the time required for all the proliferative cells to be labelled with BrdUrd (reflecting the maximum cell-cycle time) was estimated to be 1.7 days for the normal glands, and 2.7 days for minute signet-ring-cell carcinomas. From the labelling index with BrdUrd as well as from the morphology, earliest carcinomas were identified in the single gland. There remained atrophic normal epithelium commonly in the single-gland lesions. Proliferative atypical cells appeared to be shed into the stroma passively through the atrophy and subsequent collapse of the gland rather than through active invasion. This may be a reason why cancer cells in minute signet-ring cell carcinomas preserved the normal pattern of cell renewal movement to form the layered structure.

Histogenesis of hyperplastic polyps of the stomach in terms of cellular proliferation.

We investigated the histogenesis of hyperplastic polyps of the stomach, in terms of cellular proliferation, by studying endoscopically removed and gastrectomized human gastric polyps either labeled with bromodeoxyuridine (BrdU) by in vitro flash labeling techniques or labeled in an isolated organ circulation system, in both of which, perfluorochemical artificial blood was employed. Immunohistochemistry with antibodies against BrdU and proliferating cell nuclear antigen (PCNA) was simultaneously employed. The generative cell zone of pedunculated and semipedunculated polyps was markedly expanded compared with that of the background mucosa, and this change also appeared in sessile polyps, although to a lesser degree. Enhanced proliferative activity was observed in both epithelial and stromal cells in areas of erosion. Our results demonstrate that the initial change in the histogenesis of hyperplastic polyps is an expansion of the generative cell zone, followed by interstitial edema and stromal cell proliferation, and that erosion can facilitate these changes. No correlation was found between the size of the polyps and the labeling indices. This finding explains, in part, the diversity of chronological changes in the size and shape of hyperplastic polyps.

Ischemic hepatitis induced by mesenteric volvulus in a patient with chronic obstructive lung disease.

A 66-year-old man with chronic obstructive lung disease was admitted to our hospital, presenting with mesenteric volvulus and mild liver injury. A superior mesenteric angiogram revealed that the arteries supplying the small intestine were twisted in the arterial phase, while the portal vein was not visualized in the late phase. A celiac angiogram demonstrated that portal blood flow from the splenic venous return was maintained. The patient's symptoms had almost resolved the day after admission, and his serum transaminases level had gradually decreased to normal with conservative therapy. A superior mesenteric angiogram on the 13th hospital day showed a normal arteriogram and the portal vein demonstrated blood flow from the superior mesenteric vein. Liver biopsy revealed hemorrhagic necrosis around the central veins, which was compatible with ischemic hepatitis. Since the patient's O2 saturation level on admission was not low enough to have caused ischemic hepatitis by itself, we suspect that a sudden decrease in portal blood flow was the additional factor that allowed the threshold for the initiation of ischemic liver damage to be reached.

Nerve contact with muscle component in neuromuscular hamartoma.

Neuromuscular hamartoma is a very rare soft tissue tumor, of which only 20 cases have been reported previously. None of these reports has described the relation between hamartomatous skeletal muscle and nerve fibers in the tumor. We experienced a patient with neuromuscular hamartoma arising at the brachial plexus. In this tumor, the localization of synaptophysin (SYP), S-100 protein (SP), neuron-specific enolase (NSE) neurofilament protein (NFP) and myoglobin (MG) was immunohistochemically detected. The results showed that SYP and MG were diffusely localized in the hamartomatous muscle fibers, SP in the schwann cells, and NSE and NFP in the axons of the hamartomatous nerve. Therefore, it is suggested that in the neuromuscular hamartoma, the structure of the neuromuscular junction may be similar to that in the motor end-plate of the normal muscle, but it may not be functional, because the hamartomatous muscles could not contract by nerve stimulation.

Radial magnetic resonance imaging and pathological findings of acetabular labrum in dysplastic hips.

Radial MRI findings and pathological changes were comparatively examined in the acetabular labrum of 11 hips of 11 patients, who underwent total hip arthroplasty for osteoarthritis due to acetabular dysplasia. Diffuse high signal pattern on the radial MR images corresponded to histological degeneration of the labrum. High signal pattern which was equivalent to the synovial fluid, showed an intralabral tear. In the obscure areas of MR images, severe impairment of the labrum such as rupture, detachment, and displacement were found.

Malignant endocrine carcinoma of the stomach.

Small cell carcinoma and small portions of poorly differentiated adenocarcinoma of the stomach sometimes differentiate into secretory cells. We experienced a pure endocrine carcinoma of the stomach. The patient, who had a giant mass in the greater curvature of the body of the stomach and regional lymph node metastasis, underwent total gastrectomy. Immunohistologic staining of the resected specimens revealed that the tumor was an endocrine carcinoma. The tumor cell shape in the present case was polygonal or oval and the cell size was relatively large. The cell nucleus was coarse chromatic and nucleoli were seen, whereas, the nucleus of small cell carcinoma often shows a fine chromatic pattern and nucleoli are not seen. On the basis of these findings, the present case was considered to be a pure endocrine carcinoma which was not classified as a small cell carcinoma.

Langerhans cell histiocytosis of an adult with tumors in liver and spleen.

We describe a 58-year-old male with multiple histiocytic tumors in the liver and spleen. Multiple tumors in the liver and spleen were seen by image analysis, and splenectomy showed a large splenic tumor with a small nodule and a swelling lymph node in the hilus. Histological features of the tumors in the liver and spleen revealed proliferation of histiocytic cells with large and clear cytoplasm and a horseshoe-shaped nucleus. Immunohistochemical studies revealed the presence of S-100 protein and CD1a antigen in the tumor cells, and neither lymphocytic marker nor lysozyme was detected. No definite Birbeck granules were seen ultrastructurally, thus the tumor cells could be classified into Langerhans cell type without Birbeck granules. Administration of adriamycin, vincristine, cyclophosphamide and prednisolone reduced size and number of the liver tumors, and the histiocytic cells could not be detected in repeatedly biopsied tissue from liver tumor. We present the clinical, immunohistological and cytological features in a visceral type of adult Langerhans cell histiocytosis, which responded well to chemotherapy.

[Decrease of nosocomial bacteremia and nosocomial pneumonia after introduction of preventive measures of hospital infection].

In the early 1980's methicillin-resistant staphylococcus aureus (MRSA) was reported as a major pathogenic organism of geriatric hospital infection in Japan. At the same time in the A geriatric hospital MRSA infection was prevalent. To decrease nosocomial infections some active preventive measures against hospital infection were taken since Oct. 1991. About a year before introduction of prevention of hospital infection in the geriatric ward (190 beds) of A hospital 193 episodes of nosocomial bacteremia were observed. However a year after introduction of preventive measures episodes of nosocomial bacteremia were decreased to less than a half (45.6%) in comparison to the number before introduction of prevention. As a causative organism gram-positive bacteria including MRSA were markedly decreased. Major portals of entry of bacteremia (74.9%) were urinary-tract system, intravenous hyperalimentation (IVH) catheter, and pressure sores. MRSA-positive pressure sores were decreased to 20.4% of those before prevention. On the other hand 87 episodes of nosocomial pneumonia were observed before prevention. However a year after introduction of preventive measures episodes of nosocomial pneumonia were decreased to less than a half (44.8%) in comparison to the number before introduction of prevention. After prevention MRSA and mixed infection of P. aeruginosa and MRSA were markedly decreased. The decrease of bacteremia and nosocomial pneumonia were caused by cleaning hands, the preventive measures for decrease and improvement of pressure sores, cleaning the upper respiratory tract for prevention of lower respiratory-tract infection cleaning floors and education of the staff, etc.

[Coagulase typing of Staphylococcus aureus in the geriatric wards after introduction of preventive measures of hospital infection].

In the early 1980's methicillin-resistant Staphylococcus aureus (MRSA) was reported as a major pathogenic organism of geriatric hospital infection in Japan. At the same time in our geriatric wards, including 190 beds, MRSA infection was prevalent. In the early 1980's in our geriatric wards minocycline was one of the most sensitive antibiotics to MRSA isolated in our wards and used frequently against MRSA pneumonias and bacteremia. In the late 1980's resistant strains of MRSA to minocycline rapidly increased because vancomycin was not allowed to introduced for treatment of MRSA before 1991 in Japan. At the same period the predominant coagulase type changed from type II to type VII. To decrease minocycline-resistant strains to MRSA after 1987, use of minocycline was limited. Moreover since Oct. 1991 to decrease nosocomial infections some active preventive measures against hospital infection, including limited use of 2nd and 3rd cephems, were taken. In this study changing patterns of coagulase type of Staphylococcus aureus were discussed. At least 4 years was needed to find out that the predominant coagulase type changed from type VII to type II again in 1991. In this study about 22 antimicrobial agents MICs of 313 strains of Staphylococcus aureus isolated between March 1992 and June 1993 were determined and compared with the data of MICs before introduction of preventive measures. The pattern of susceptibility to MINO was in part improved. Thus the some sensitive strains of S. aureus were observed again in our geriatric wards. Interestingly indeed it took approximately 5 years to find out the emergence of sensitive strains to MINO since limitation of use of MINO in 1987.

The current status of medicolegal issues surrounding telepathology and telecytology in Japan.

The medicolegal issues surrounding telepathology and telecytology in Japan have been partly resolved since the government declared that telediagnosis in these fields using a microscope is essentially a medical practice between doctors. Thus it does not contravene article 20 of the law pertaining to medical practice in Japan, which states that there must be an actual face-to-face encounter between the doctor performing any diagnostic or treatment episode and the patient. It is, however, only beginning to be recognized that the medicolegal issues surrounding telepathology and telecytology depend on factors such as the type of system used (e.g. active versus passive). In an active diagnostic system, the telepathologist or telecytopathologist can control a robotic microscope at the remote site, while in a passive diagnostic system the telepathologist or telecytopathologist makes the diagnosis based on the microscope images that have been selected, and transmitted, by someone in the remote hospital. In the former case the interpreting telepathologist or telecytopathologist must assume most of the responsibility for the diagnostic process, while in the latter more responsibility must be assumed by those at the remote site. The duties and responsibilities of all participants in the telediagnostic process, whatever the system employed, must be determined. We have established working guidelines for telepathological and telecytological diagnoses to help achieve this and hence ensure safe and effective clinical practice.

The basic diagnostic approaches used in robotic still-image telepathology.

We investigated the basic diagnostic processes used in telepathology with our robotic still-image system, OLMICOS, by analysing the steps and patterns used in 20 consecutive tissue section diagnoses. Three basic approaches were recognized. One was magnifying a suspect finding in a low-powered microscopic image. This approach was used mostly for confirming or characterizing a tumour. The second approach was scanning over a low-powered image by magnifying square images to form a mesh. This was found to be useful to confirm the presence or absence of signs and was mostly used as the initial step in judging the surgical margin of malignant cases or diagnosing lesions. The third approach was a combination of these two and was used for delineating the surgical margin, confirming the absence of metastases or diagnosing difficult lesions. Recognition of these three basic diagnostic approaches is important in making a rapid and correct remote diagnosis.

[A case of atypical polypoid adenomyoma with intramural myoma-like growth].

We encountered a case of a large atypical polypoid adenomyoma (APA) which showed characteristic intramural appearance. As many cases of APA of the uterus have been reported in recent years, macro- and microscopic findings of the lesion and its clinical characteristics have been investigated. However the pathogenesis and the natural history of the lesion remained to be solved owing to still limited number of the cases. We report this case to discuss the macroscopic findings and clinicopathologic characteristics of the lesion.

[Biology of cancer cell-stroma interaction in carcinogenesis and cancer progression].

Cancer cells are dependent on physical and chemical supports of stroma no less than non-cancerous cells and tissues are. The role of stroma should, therefore, be important in genesis and progression of cancers growing in vivo. But this aspect underlying carcinogenesis and manifestation of human cancers has long been neglected or attracted less attention in the investigations of oncology. Focusing particular attention on parenchyma-stromal interaction in gastrointestinal mucosa, the authors have found that, quite unexpectedly, in normal gastric as well as intestinal mucosa of all the animal species so for studied, vascularity is always poorly developed in the generative cell zones. Cross-sectional area of vascular bed is markedly reduced in this zone. Application of Hagen-Poiseulle law revealed that the reduced total cross-sectional area, resulting in a rapid drop in hydrostatic pressure, creates here a situation particularly favorable for proliferating cell population. Since the transport of water soluble material together with tissue fluid through the capillary wall is driven by the hydrostatic pressure, the generative cell zones are found to be present at the site where the turnover of the material is the most active. Before the zone of the rapid pressure drop, there appears zone of relatively high intravascular hydrostatic pressure, where secretory function seems to be facilitated. This zone, as is well known, corresponds to glandular portion of the mucosa. After the zone of the rapid pressure drop (in surface of the mucosa), zone of a low intravascular hydrostatic pressure appears, where absorptive function is to be facilitated. Within such zones, in gastric mucosa surface epithelium and in intestinal mucosa absorptive villi cells are located. It is likely that architecture of gastrointestinal epithelium and vascular pattern in the stroma is closely correlated and that the former is determined, at least partly, by the latter. When human gastric mucosa shows intestinal metaplasia, the vascular pattern is always of the type of intestine. Investigating causal relationship of the changes in vascular pattern and epithelial metaplasia, we found that, in human gastric mucosa, vascular architecture began to shift to the intestinal pattern, though not complete, when incipient changes of chronic gastritis became manifest. This is peculiar to human gastric mucosa and thought to be species specific characteristics of mucosal stroma in human stomach.(ABSTRACT TRUNCATED AT 400 WORDS)