ABSTRACT:The synthesis of novel superabsorbent hydrogels was investigated with the reaction of cotton cellulose and succinic anhydride (SA) in the presence of 4-dimethylaminopyridine as an esterification catalyst in a mixture of lithium chloride (LiCl) and N-methyl-2-pyrrolidinone (NMP) or in a mixture of tetrabutylammonium fluoride (TBAF) and dimethyl sulfoxide (DMSO), followed by NaOH neutralization. Interestingly, a hydrogel was obtained without any crosslinking agent, and this indicated the partial formation of a diester between the cellulosic hydroxyl group and SA. The products obtained in LiCl/NMP exhibited superior absorbency to these obtained in TBAF/DMSO. The former absorbed an amount of water about 400 times its dry weight, and this was comparable to a conventional sodium polyacrylate superabsorbent hydrogel. Furthermore, in an aqueous NaCl solution, the absorbency of the product hydrogels was higher than that of the sodium polyacrylate superabsorbent hydrogel. The formed hydrogels biologically degraded almost completely after 25 days, and this showed their excellent biodegradability. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: [3251][3252][3253][3254][3255][3256] 2006

1 The present study was addressed to clarify the subtypes of P2-purinoceptor involved in ATP release and contraction evoked by a,b-methylene ATP (a,b-mATP) and other P2-agonists in guinea-pig ileum. 2 a,b-mATP 100 mM produced a transient and steep contraction followed by ATP release from tissue segments. These maximum responses appeared with di erent time-courses and their ED 50 values were 5 and 25 mM, respectively. The maximum release of ATP by a,b-mATP was markedly reduced by 250 mM suramin, 30 mM pyridoxal-phosphate-6-azophenyl-2',5'-disulphonic acid (PPADS) and 30 mM reactive blue 2 (RB-2), P2-receptor antagonists. However, the contractile response was inhibited by suramin, tetrodotoxin and atropine, but not by PPADS and RB-2. 3 Although the contraction caused by a,b-mATP was strongly diminished by Ca 2+ -removal and nifedipine, and also by tetrodotoxin and atropine at 0.3 mM, the release of ATP was virtually una ected by these procedures. 4 UTP, b,g-methylene ATP (b,g-mATP) and ADP at 100 mM elicited a moderate release of ATP. The release caused by UTP was virtually una ected by RB-2. However, these P2-agonists failed to elicit a contraction of the segment. 5 The potency order of all the agonists tested for the release of ATP was a,b-mATP4UTP4b,gmATP4ADP.6 In superfusion experiments with cultured smooth muscle cells from the ileum, a,b-mATP (100 mM) enhanced the release of ATP 5 fold above the basal value. This evoked release was inhibited by RB-2. 7 These ®ndings suggest that ATP release and contraction induced by P2-agonists such as a,b-mATP in the guinea-pig ileum result mainly from stimulation of di erent P2-purinoceptors, P2Y-like purinoceptors on the smooth muscles and, probably, P2X-purinoceptors on cholinergic nerve terminals, respectively. However, the ATP release may also be mediated, in part, by P2U-receptors, because UTP caused RB-2-insensitive ATP release.

SUMMARY Moyamoya disease was originally defined as a characteristic syndrome of recurrent headaches, occlusion of the distal internal carotid arteries and the foggy (moyamoya) clusters of collateral vessels at the base of the brain as demonstrated by cerebral angiography. The etiology is unknown and pathobiology is poorly understood. We examined the intracranial arteries in 3 patients to demonstrate characteristic changes and to obtain a better understanding of the basis mechanisms of the disease. Controls were obtained from 3 normotensive patients who died as a result of cancer. Occluded internal carotid arteries were characterized by severe thickening of the intima with a dense luminal array of smooth muscle cells, a deeper less cellular zone, pronounced tortuosity of the internal elastica and thinning of the media. Collateral vessels were arterial in structure and were affected by similar prollferative changes in the intima, thinning of the media, and contorted internal elastica. Stainable lipids were not part of the typical components. Severe contortion of the internal elastica, medial damage and intimal proliferation may result from recurrent and sustained spasticity of the cerebral arteries. The distal lenticulostrlate arteries showed severe medial damage similar to what is termed as a moth-eaten change in hypertensive patients dying of massive cerebral hemorrhage. Stroke Vol 15, No 4, 1984ARTERIAL CHANGES IN MOYAMOYA DIS-EASE, as shown by angiography of the distal internal carotid artery, reveal lipid-free fibromuscular thickening and the development of presumably newly formed collateral vessels at the base of the brain.' These collaterals are so characteristic that the term moyamoya vessels has been applied to them. 2 Occlusion of the internal carotid artery caused by atherosclerosis, is not accompanied by the appearance of collateral vessels and is characterized by the presence of stainable lipids.The term moyamoya disease was coined for the "foggy" collateral channels demonstrable by cerebral angiography.2 The disease is relatively uncommon and shows no relationship to systemic hypertension. This disease was first reported in, but it is not confined to, the Japanese. The condition is frequently familial, and may occur in infants and children as well as in adults.1 4 The pathogenesis is unknown and the possibilities include genetic factors.3 3 Intracerebral and subarachnoid hemorrhages are frequent complications. 6 Moyamoya disease of the juvenile type often manifests itself by transient ischemic attacks, and the adult type usually presents as a massive intracerebral hemorrhage.* Thus moyamoya disease provides an interesting model for studies of arterial disease and its complications. The histologic features and morphometry of arterial changes in 22 patients with moyamoya disease have been reported by others. 7The present study was undertaken to characterize ultrastructural changes of the circle of Willis and collateral moyamoya vessels, and to obtain a better un- derstanding of the basic mechanisms of ...

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An autopsy case with intravascular bronchioloalveolar tumor occurring in a 51‐year‐old Japanese woman is reported. The lungs contained multiple nodules which were characteristic features of this tumor. In addition, the tumor diffusely involved bilateral lower lobes associated with extensive pleural invasion. and the tumor tended to spread along vascular and bronchial trees. No extrathoracic metastasis was noted. Histologically, the nodules showed hypocellular hyaline or myxoid tissue surrounded by peripheral cellular layers. Diffuse consolidated areas were composed of collagenous connective tissue with scattered tumor cells. Factor VIII‐related antigen could not be demonstrated in tumor cells, but the negative result was considered to be secondary to antigen deterioration by delayed fixation of the tissue. Electron microscopic examination did not support the alveolar epithelial cell origin, but revealed morphological characteristics of myofibroblasts and endothelial cells. The tumor is presumed to be derived from vascular stem cell with a tendency of endothelial differentiation. ACTA PATHOL. JPN. 35 : 631–642, 1985.