A case of surgical repair in type A aortic dissection with intimal laceration extending into the noncoronary Valsalva sinus

A 50-year old man who had acute type A aortic dissection, underwent prosthetic graft replacement of the ascending aorta. Intimal laceration of the ascending aorta was extending into the noncoronary Valsalva sinus just near the aortic annulus, but the competency of the aortic valve was preserved. Reconstruction of the noncoronary sinus was achieved by approximating intimal edge with Teflon felt reinforced buttress suture, then the ascending aorta was replaced by a Dacron prosthetic graft. His postoperative recovery was uneventful.     

Collagen abnormalities in the spinal cord from patients with amyotrophic lateral sclerosis

During the last 10 years, we have demonstrated morphological and biochemical abnormalities of skin extracellular matrices in amyotrophic lateral sclerosis (ALS). However, currently little is known concerning collagen of the spinal cord in ALS. We measured the amount of collagen and characterized collagen at light and electron microscopic levels in posterior funiculus, posterior half of lateral funiculus and anterior horn of cervical enlargement of the spinal cord obtained from ten patients with ALS, 11 patients with other neurologic diseases (control group A), and ten patients without neurologic ones (control group B). In posterior half of lateral funiculus and anterior horn, (1) by light microscopy, there was no significant difference in vessel wall area between ALS patients and control groups A and B; (2) ultrastructurally, collagen bundles were more fragmented and widely separated, and the fibrils were randomly oriented in the perivascular space of capillaries in ALS patients, which were not observed in any areas of control groups or in posterior funiculus of ALS patients; and (3) the collagen contents in ALS were significantly lower (P<0.001 and P<0.001, respectively) than those in control groups A and B. Fragmented and widely separated collagen bundles in the interstitial tissue surrounding capillaries and markedly decreased amount of collagen in posterior half of lateral funiculus and in anterior horn of ALS could be related to the degeneration of the upper and lower motor neurons in the spinal cord in ALS, that is, selective neuronal vulnerability in ALS.     

Elevated anti-alginate serum titers in patients with acute cholangitis and gallstones imbedded withPseudomonas aeruginosa

Electron microscopy and bacteriological culture revealed viable bacteria covered with a glycocalyx (biofilm) in choledochal stones recovered from two patients with acute cholangitis. On the cut surface of the choledochal stones, the cholesterol stone component was surrounded with a layer of brown pigment stone. In each case, bacterial culture of the choledochal stone recoveredPseudomonas aeruginosa. Since alginate is the main component of the glycocalyx produced byP. aeruginosa, serum IgM, IgG and IgA anti-alginate antibodies were measured in each patient. The present study is the first to demonstrate acute and transient IgM seroconversion to alginate in cases of acute cholangitis. In one case, the elevation of anti-alginate IgM preceded the elevation of anti-alginate IgG. The authors propose that the bacterial glycocalyx may play a significant role in acute cholangitis.     

Ultrastructure of early phase hepatic metastasis of human colon carcinoma cells with special reference to desmosomal junctions with hepatocytes

To demonstrate ultrastructural events in the early phase of hepatic metastasis of human colon carcinoma, we intrasplenically injected a highly metastasizable, human colon carcinoma cell line LM-H3 (1 x 10(6) cells) into nude mice, and electron microscopically investigated the hepatic metastasis. At 24 h, tumor cells adhered to the endothelial wall of terminal portal venules and periportal sinusoids. At 48-72 h, after extravasation, they deeply invaded the hepatic cell plate and the interstitial tissue of the portal tract, in which they underwent proliferation and made the metastatic foci. Tumor cells were linked with each other or with surrounding hepatocytes by desmosomes. Desmosomes were maintained during the mitosis. When invading tumor cells were exposed to the bile canaliculi, they generated microvilli on the surface. Microvilli were also formed at the luminal surface of intracytoplasmic inclusions. In the interstitial tissue of the portal tract, tumor cells were closely associated with fibroblasts. However, no junctional specializations were seen between them. The present study demonstrated that human colon carcinoma cell line LM-H3 formed desmosomes with hepatocytes soon after invasion of the hepatic cell plate, suggesting the regulatory role of an interaction with hepatocytes in the growth of metastatic foci within the liver parenchyma.     

Characterization of NK cells and extrathymic T cells generated in the liver of irradiated mice with a liver shield

We previously reported that c-kit⁺ stem cells which give rise to extrathymic T cells are present in the liver of adult mice. Further characterization of extrathymic T cells in the liver of adult mice is conducted here. When mice with a liver shield were lethally (9.5 Gy) irradiated, all mice survived. All tested organs showed a distribution pattern of hepatic lymphocytes on day 7. The distribution pattern in the liver was characterized by an abundance of NK (CD3^? IL-2Rβ⁺) and extrathymic T cells (CD3^int IL-2Rβ⁺) before and after irradiation. To determine their function, post-irradiation allogeneic bone marrow transplantation (BMT) was performed in mice with or without a liver shield. Allogeneic BM cells were rejected in mice with a liver shield and specific activation of CD8⁺ CD3^int IL-2Rβ⁺ cells was induced. At that time, potent cytotoxicity of liver mononuclear cells (MNC) against allogeneic thymocytes was induced. Both NK1.1⁺ and NK1.1^? subsets of CD3^int cells expanded in these mice. An in vivo elimination experiment of the subsets indicated that the NK1.1⁺ subset of CD3^int cells (i.e. NK T cells) was much more associated with the rejection of allogeneic BM cells. However, even after the elimination of NK T cells, allogeneic BM cells were rejected. In this case, granulocytes expanded in parallel with NK1.1^? subsets. Granulocytes may also be associated with the rejection of allogeneic BM cells. These results suggest that the liver is an important haematopoietic organ even in adult life.     

SOLITARY GASTRIC POLYPS IN THE FUNDIC GLAND AREA A Histochemical Study

Six solitary gastric polyps in the acid-secreting fundic mucosa were histo-chemically investigated using the mucin histochemistry, immunoperoxidase method, and silver methods for endocrine cells. Histologically, the polyps were grouped into three types : they largely consisted of either hyperplastic foveolar cells (group 1), normal-appearing fundic gland cells with mild cystic changes (group 2) or hyperplastic fundic gland cells with cystic dilatation (group 3). The presence of parietal cells and mucous neck cells was confirmed in all polyps by the immunoperoxidase method using parietal cell autoantibody and the paradoxical Concanavalin A staining, respectively. Regarding the endocrine component, somatostatin-containing cells, Grimelius-positive argyrophil cells, and Fontana-Masson-positive enterochromaffin cells were scattered in the fundic gland area of the polyps as well as in the surrounding normal-appearing fundic mucosa. Gastrin-containing cells were absent. In one of the group 2 polyps and both group 3 polyps, a varying number of glicentin-containing cells were found among the fundic gland components : In one polyp in group 3, glucagon immunoreactivity was detected in the glicentin-containing cells. These findings suggest that some of the polyps express characteristics of the fetal fundic mucosa, since glicentin and glucagon immunoreactivities in normal human stomach have been detected exclusively in the fetal fundus. ACTA PATHOL. JPN. 35: 831–840, 1985.     

Development of sutureless vascular connecting system for easy implantation of small-caliber artificial grafts

A novel sutureless vascular connecting system, an assembly with a delivery rod, an introducing sheath, and a connecting device, was developed for easy implantation of small-caliber vascular grafts less than 2 mm in internal diameter. A microporous stainless tube (length 2 mm, external diameter 1.6 mm, wall thickness 65 µm, pore diameter 400 µm, pore-to-pore distance 500 µm) was designed to serve as a connecting device. The feasibility of the system was tested using two types of preliminary animal experiments. One animal model consisted of graft implantation into the rat abdominal aorta (1.5 mm in diameter). The connecting device was inserted into the proximal and distal ends of the aorta through the introducing sheath by pushing the delivery rod with the connecting device placed over it. Subsequently, the aortic segments were inserted into both ends of model grafts made of segmented polyurethane (1.8 mm in internal diameter) and were fixed with banding silk threads from the exterior. The procedure was completed within 20 min without requiring specialized microsurgery techniques. Blood leakage and obstruction did not occur. The second model consisted of an end-to-end anastomosis between rabbit common carotid arteries (2 mm in diameter), which was performed within several minutes of blood flow interruption. Scanning electron microscopy demonstrated that the luminal surface of the device was fully covered with endothelial cells (ECs) after 1 week as a result of transluminal ingrowth of native ECs through the micropores in the device. This endothelialization may prevent early thrombus-induced occlusion. This simple and “easy-to-learn” technique will promote the development of small-caliber arterial grafts, and furthermore, it may have potential for clinical application.     

Electron microscopic investigation of transplanted squamous cell carcinoma in nude mice

Extirpated specimens of a squamous cell carcinoma from a human thigh were transplanted to the subcutaneous tissue of nude mice. Fourteen days later, the transplanted tumor masses were, again, extirpated from the nude mice. The transplanted chimera of the squamous cell carcinoma as seen with the electron microscope resembled the tumor cells before transplantation. It is concluded that ultrastructural investigation of transplanted chimera from squamous cell carcinoma cases may be useful for examining the site of action and clinical effects of anticancer drugs on this kind of tumor.