Analysis of new imidazoline derivative-induced increase in the maximum response to norepinephrine in the rat vas deferens

The effects of newly synthesized 5-imidazoline derivatives on the dose-response relationship to norepinephrine were investigated in the normal and denervated vasa deferentia of the rat. Three derivatives (K-3827, K-4011 and K-4300) exerted alpha-antagonistic action, the potency of which was similar to that of tolazoline. The pA2 values of these derivatives and currently known alpha-antagonists (tolazoline, phentolamine and prazosin, but not yohimbine) in the denervated tissue were slightly but significantly larger than those in the normal tissue. All imidazoline derivatives and alpha-antagonists produced an increase in the maximum response to norepinephrine in the normal vas deferens. In the denervated tissue, however, K-3827, K-4011 and alpha-antagonists caused only a rightward shift of the dose-response curve to norepinephrine, but not an increase in the maximum response, i.e., relatively pure alpha-antagonism. In contrast, the other 3 imidazoline derivatives, K-4299 and K-6342 which exhibited neither alpha-agonistic nor antagonistic action and K-4300, increased the maximum response to norepinephrine even after denervation. Their effects were nonspecific in that they also potentiated acetylcholine-induced contractions in both normal and denervated tissues. These 3 imidazoline derivatives antagonized the action of diltiazem. The effects of imidazoline derivatives and alpha-antagonists were discussed in relation to those of denervation, and the drug enhancement by 3 imidazoline derivatives was analyzed from the viewpoint of calcium movement.     

A case of Ullrich disease with distinct pathological change of muscular dystrophy

A case of Ullrich disease was presented. The patient was a 3-year-old girl with torticollis, generalized muscle weakness and acroatonia since birth. High-arched palate, protruded calcaneus, and mild contracture of proximal joints were also recognized. Intellectual development was normal. Serum level of CPK was slightly increased. In histological and histochemical examinations of quadriceps femoris muscle, proliferated connective tissue, marked variation in the muscle fiber diameter, and a lot of degenerated and regenerated fibers were recognized. Minimal injury easily causes subcutaneous hemorrhage, but no abnormality was found in the structure of collagen.     

Properties of membranes from polyelectrolyte complexes consisting of methyl glycol chitosan, [2-(diethylamino)ethyl]dextran,and poly(potassium vinyl sulfate)

Water-insoluble polyelectrolyte complexes (PEC) were prepared by mixing methyl glycol chitosan (MGC, 1 ) and [2-(diethylamino)ethyl]dextran (EA, 2 ) with poly(potassium vinyl sulfate) (PVSK, 3 ) in aqueous solution at various hydrogen ion concentrations. Elemental analyses, IR spectroscopy, and solubilities of PEC reveal that PEC differ in molecular structure and properties according to pH. It seems that the degree of dissociation and the conformation of MGC, EA, and PVSK change with pH. PEC membranes were made by casting from solutions of all kinds of PEC, and transport phenomena through the membrane of PEC prepared in 4 wt.-% HCl solution were investigated under various conditions. The driving force of the transport depends on the membrance potential, Donnan potential, and diffusion potential, according to measurements of the transport ratio of Na⁺ and the electric potential difference between the left- and right-hand side of the membrane. Moreover, the permeability of K⁺ is higher than that of Na⁺.     

Current concept and future research directions of mild cognitive impairment

Alzheimer's disease (AD) generally begins with mild memory problems which occur in an insidious manner and progresses to the development of multiple cognitive impairments. There is a ‘gray’ area between what is classified as ‘normal’ and what is classified as ‘dementia’, currently called mild cognitive impairment (MCI). In this article, a case of MCI is described, and the diagnosis, assessment, subclassification (pre‐Alzheimer type and white matter lesion type) and future therapeutic plans for MCI are reviewed.     

Pancreatic metastasis of malignant melanoma diagnosed by EUS-guided fine needle aspiration (EUS-FNA)]

Pancreatic metastasis of malignant melanoma is rarely diagnosed while the patient is alive. We report a case of metastatic melanoma of the pancreas in a 35-year-old woman presenting with a solid mass of the pancreas. Her past medical history included a radical hysterectomy 2 years previously for malignant melanoma of the vagina. Twelve months later, lung metastasis was also resected. EUS-guided fine needle aspiration (EUS-FNA) identified that the pancreatic tumor was histologically and immunohistochemically identical to the surgical specimen of her lung neoplasm. Imaging studies including US, CT, and MRI have limited value to distinguish the tumors from primary ductal adenocarcinoma. EUS-FNA can provide tissue diagnosis from pancreatic masses, specifically when other modalities have failed.