Preoperative elevated serum CA19-9 and total bilirubin levels are prognostic factors for ampullary adenocarcinoma, and are both associated with pancreatobiliary-type tumors. Surgeons should be aware of these factors because pancreatobiliary-type adenocarcinoma is aggressively invasive and is associated with poor survival.

The helix is a fundamental macromolecular structure. The construction and mutation of helical structures have been studied for a variety of synthetic polymer systems.[1] Macromolecular stereomutation is triggered by chemical or thermal stimuli in most cases, and fewer examples are known of stereomutation triggered by light. Existing examples of photoinduced stereomutation involve photochromic groups incorporated into the side chains or main chain of polymers. These groups cause the isomerization of a double bond [2][3][4] or bond cleavage and formation.[5]Herein we report the synthesis of optically active preferred-handed helical poly(2,7-bis(4-tert-butylphenyl)fluoren-9-yl acrylate) (poly(BBPFA)), a novel polyacrylate, and its effective racemization induced by photoirradiation. In contrast to the previous examples, [2][3][4][5] the stereomutation observed for this polymer is governed by simple rotation about the single bonds between the side-chain fluorenyl moieties and the tert-butylphenyl substituents without any changes in chemical bonding.Polymerization was carried out with the complex formed between 9-fluorenyllithium (FlLi) and (+)-1-(2-pyrrolidinylmethyl)pyrrolidine (PMP) as the initiator in toluene at À78 8C (Scheme 1, Table 1). This initiator system has been used to synthesize preferred-handed helical polymers from bulky (meth)acrylates.[1a,b, 6] The polymerization of BBPFA occurred with almost quantitative monomer conversion. The observed increase in M n with an increase in the [BBPFA]/[FlLi] ratio (from 10:1 to 40:1) implies that the polymerization has "living" characteristics to a certain extent. Polymerization was also attempted at a [BBPFA]/[FlLi] ratio of 60; however, the reaction system gelled owing to poor solubility of the products, and relatively low monomer conversion (37 %) resulted.The obtained polymers were optically active and exhibited intense circular dichroism (CD) spectra (Figure 1). Optical activity and CD intensity increased with an increase in the M n value of the polymer. These results, combined with the fact that BBPFA monomer does not have any configurational chirality, strongly suggest that the observed chiroptical properties can be ascribed to a preferred-handed helical polymer conformation. This conclusion is supported by the Scheme 1. Asymmetric polymerization of BBPFA. Entry ½BBPFA ½FlLi Conv. [b] [%]Yield [c] [%]

Free-radical polymerization of dibenzofulvene (DBF) was carried out under various conditions. The radical polymerization proceeded exclusively in vinyl fashion without isomerization of the growing radical or aromatic substitution by the initiator fragment. The polymerization was highly conformation-specific (stereospecific), giving a polymer with a π-stacked conformation in which the main-chain C−C bonds are nearly all trans and the side-chain fluorene moieties are stacked on top of each other. The conformation specificity (stereospecificity) of the DBF radical polymerization was almost similar to that in the anionic polymerization although the radical polymerization products appeared to have a small amount of irregular, defective conformation incorporated into the mostly π-stacked chain. The conformation specificity was affected by the initial monomer concentration and reaction temperature. This observation was explained by a proposed mechanism where two types of the growing radicals having different conformations mediate the polymerization. The poly(DBF) obtained by the radical polymerization showed lower fluorescent intensity and higher solubility possibly due to a small amount of conformational defects.

No abstract

: Background. Hepatocellular carcinoma is likely to accompany liver cirrhosis in which the portal pressure increases with portasystemic shunt. When portal tumor thrombus is present in the primary bifurcation, blood flow differs between the thrombolic lobe and the non-thrombolic lobe. In those cases, it is difficult to evaluate exactly residual liver function by conventional test. Therefore, the following studies were performed.Materials and Methods. Adult mongrel dogs are divided into a control group (C group), group undergoing ligation of the left portal branch (PL group), group undergoing portacaval anastomosis (PCS group) and group undergoing both ligation of the left portal branch and portacaval anastomosis (PL+PCSgroup)(n=5). ICG-R15 and MEGX15 in peripheral venous blood and right hepatic venous blood were determined. Mitchondrial metabolic capacity (adenosine triphosphate level, energy charge) was measured by high-performance liquid chromatography using liver biopsied specimens.Results