Associations between restriction fragment length polymorphisms detected with a probe for human C4 and allotype of C4B5 allele

We studied the fourth component of human complement (C4) allotypes in 58 Japanese individuals. The technique of Southern, with C4 and 21-OH cDNA probes, was used to examine the genomic DNA of 45 individuals typed for C4 by protein electrophoresis. Novel HindIII C4 10- and 5-kb and EcoRI C4 13-Kb restriction fragments were identified in each of nine Japanese individuals. The novel fragments were different from the previously described C4B long (HindIII 31-kb, TaqI 6-kb, BamHI 4.3-kb, and EcoRI 12-kb) and C4B short (HindIII 25-kb, TaqI 5.4-kb, BamHI 3.5-kb, and EcoRI 15-kb) fragments. All novel HindIII- and EcoRI-positive individuals carried C4B5, BfS, and HLA-Bw54. Therefore, the fragments were characteristic for the C4B5 allele. The C4 region was analyzed to determine the restriction sites by single and double digests of uncloned genomic DNA with several restriction endonucleases. It is speculated that an insertion gene lies between the 3' end of the 21-OH and the 5' end of the C4B genes.     

Polymorphous low-grade adenocarcinoma of submandibular gland origin

A case of polymorphous low-grade adenocarcinoma (PLGA) in the submandibular gland is reported. A 72 year old woman presented with a 5 year history of a gradually expanding tumor in the submandibular region. The surgical specimen revealed a relatively well demarcated tumor, 35 × 35 × 20 mm in size. Macroscopically, necrosis and hemorrhage were not seen in the solid tumor. Histologically, the tumor growth pattern was variable, composed of tubular, papillary, solid, trabecular and cribriform structures. Immunohistochemically, some tumor cells were positive for epithelial membrane antigen (EMA), S-100 protein, keratin, and carcino-embryonic antigen (CEA). Electron microscopically, prominent microvilli projected into the luminal spaces, and basal lamina and hemidesmosomes were seen in the tumor cells adjacent to the connective tissues. The submandibular gland is an extremely rare location for PLGA. To the authors' knowledge, this is the first case of its kind reported in the English literature.     

A combination analysis of p53 and p21 in gastric carcinoma as a strong indicator for prognosis

We studied p53 and p21 expression simultaneously in gastric carcinoma tissues to investigate the clinical significance of p53-p21 pathway in this disease. One hundred sixty-four primary gastric carcinoma specimens were immunohistochemically stained for p53 and p21 protein, and clinicopathological features of the cases were examined. P53 was stained negatively, while p21 was stained positively in each normal stomach epithelium. P53, and p21 positive staining was observed in 82 (50%) and 61 (37.2%) tumors, respectively. Unexpectingly, no correlation was found between p53 and p21 staining status. Tumors demonstrating preserved p53-p21 pathway [p53(-)/p21(+)], observed in 20.1% of the tumors, displayed less aggressive characteristics, and no recurrent disease after curative resection. While tumors demonstrating disrupted p53-p21 pathway [p53(+)/p21(-)], observed in 32.9% of the tumors, displayed significantly more aggressive characteristics, poorer survival and higher recurrence rate than the tumors demonstrating other staining patterns. P53-p21 pathway was widely altered in gastric carcinomas. The combined evaluation of p53 and p21 expression in gastric carcinoma tissues is suggested to have clinical importance by indicating not only the malignant potential of each tumor, but also the prognosis of this disease.     

Antifungal activities of tacrolimus and azole agents against the eleven currently accepted Malassezia species

The lipophilic yeast Malassezia is an exacerbating factor in atopic dermatitis (AD) and colonizes the skin surface of patients with AD. With the goal of reducing the number of Malassezia cells, we investigated the antifungal activities of a therapeutic agent for AD, tacrolimus, and the azole agents itraconazole and ketoconazole against Malassezia species in vitro. We examined 125 strains of the 11 currently accepted Malassezia species by using the agar dilution method. All strains of the 11 Malassezia species were very susceptible to both azole agents, with MICs ranging from 0.016 to 0.25 mug/ml. Tacrolimus had antifungal activities against half of the strains, with MICs ranging from 16 to 32 mug/ml. Two of the major cutaneous floras, Malassezia globosa and Malassezia restricta, have several genotypes in the intergenic spacer region of the rRNA gene; the azole agents had slightly higher MICs for specific genotype strains of both microorganisms. A combination of azole agents and tacrolimus had a synergistic effect against Malassezia isolates, based on a fractional inhibitory index of 0.245 to 0.378. Our results provide the basis for testing these agents in future clinical trials to reduce the number of Malassezia cells colonizing the skin surface in patients with AD.     

Anesthetic induction agents, sympathetic nerve activity and baroreflex sensitivity: a study in rabbits comparing thiopental, propofol and etomidate

The mechanisms of arterial hypotension following intravenous anesthetic induction agents are multifactorial. The purpose of this study was to evaluate and compare the effects of thiopental, propofol and etomidate on hemodynamics, sympathetic outflow and arterial baroreflex sensitivity using not only neuraxis-intact but also totally baro-denervated rabbits. A total of 60 rabbits was anesthetized with urethane, tracheotomized, and mechanically ventilated with oxygen in nitrogen (FiO2 0.5). The left renal sympathetic nerve was isolated and placed on a bipolar electrode to record renal sympathetic nerve activity (RSNA). Thirty animals underwent a surgical preparation of total baroreceptor denervation. Bolus injections of an anesthesia induction dose of thiopental 4 mg/kg and twice the induction dose of propofol 4 mg/kg significantly decreased RSNA to the same extent (19.4+/-6.7 and 19.7+/-5.2% reduction, mean +/- SEM) and mean arterial pressure (MAP) also to the same extent (19.5+/-4.6 and 22.1+/-3.1% reduction) in the neuraxis-intact animals. RSNA was increased (34.5+/-6%) without reduction of MAP by an induction dose of etomidate, 0.3 mg/kg. Sympathetic barosensitivity was attenuated even 10 min after thiopental at 4 mg/kg or propofol at 4 mg/kg (68% and 54% of control, respectively). Propofol at 2 mg/kg (induction dose) and etomidate at 0.6 mg/kg decreased RSNA and MAP only in the baro-denervated animals. It was found from the barosensitivity study that patients can be hemodynamically unstable even though blood pressure has returned to normal after thiopental and propofol administration. Data suggest that etomidate can even stimulate the sympathetic nervous system and increase sympathetic outflow. It was also clearly found from the baro-denervated animal study that thiopental was stronger than propofol in directly suppressing sympathetic outflow at the induction dose.     

Vascular reserve in chronic cerebral ischemia measured by the acetazolamide challenge test: comparison with positron emission tomography.

PURPOSETo determine the value of the acetazolamide challenge test with stable xenon-enhanced CT (Xe CT) for making therapeutic decisions in patients with chronic cerebrovascular disease.METHODSWe compared the Xe CT-measured acetazolamide response with various measures obtained by positron emission tomography. We performed both a positron emission tomographic scan and a Xe CT study in 11 patients with chronic cerebral ischemic diseases within a 1-week interval. An increase of cerebral blood flow after injection of acetazolamide was expressed as delta AT. Regional cerebral blood flow, cerebral oxygen metabolism, oxygen extraction fraction, and cerebral blood volume were measured with oxygen-15-labeled gases by positron emission tomography.RESULTSIn low-cerebral blood flow regions, decreased delta AT was accompanied by a significant elevation of oxygen extraction fraction and cerebral blood volume, compared with oxygen extraction fraction and cerebral blood volume in regions of normal delta AT. Plotting of regional data indicated that delta was significantly dependent on oxygen extraction fraction and cerebral blood volume. The area of decreased vascular reserve determined by the Xe CT image corresponded to the area of "misery perfusion" determined by positron emission tomography.CONCLUSIONThe acetazolamide challenge test with Xe CT may offer an alternative to positron-emission tomography in detecting lesions with elevated oxygen extraction fraction and cerebral blood volume (misery perfusion) that result from chronic hemodynamic stress.     

Cerebellopontine angle pilocytic astrocytoma mimicking acoustic schwannoma

We describe a case of pilocytic astrocytoma of the cerebellum mimicking an acoustic schwannoma. The tumour protruded into the porus acusticus and enlarged the internal auditory meatus, which is a quite unusual characteristic of glial tumours. Received: 2 February 1999 Accepted: 21 April 1999     

Effect of UDP-glucuronic acid on the microsome-mediated binding of benzo(a)pyrene metabolites to calf thymus DNA

The binding of benzo(a)pyrene (BP) to DNA in the presence ofliver microsomal preparations from 3-methylcholanthrene-treatedrats was increased 28.5% (P < 0.001) by addition of UDP-glucuronicacid to the incubation mixture at a 100 µM concentrationof BP. However this increase was not observed at lower concentrationsof BP. Analysis of DNA-hydrolysates by column chromatographyon Sephadex LH-20 indicated that this increase was due to greaterbinding of benzo(a)pyrene-7, 8-dihydrodiol-9, 10-epoxide. Theamount of bound adducts derived from 9-hydroxybenzo(a)pyrene(9-OH BP) was not significantly affected by UDP-glucuronic acid.Addition of UDP-glucuronic acid to incubation mixtures containingmicrosomes from untreated rat liver caused only a slight increasein total binding. These findings suggest that UDP-glucuronyltransferase may be involved in the activation of BP.     

Estimated affinity of isoproterenol to cardiac chronotropic beta-receptor and of phenylephrine to vasoconstrictive alpha-receptor of the systemic resistance vessels in human borderline hypertension

There has been yet no report, to our knowledge, which clarified the affinity ("sensitivity") of catecholamines to cardiac chronotropic beta-adrenergic receptor or to vasoconstrictive alpha-adrenergic receptor of skeletal muscle resistance vessels in human borderline hypertension (BHT), using an analysis of the kinetics of the drug-receptor interaction. In the first half of this study, isoproterenol (ISO) infusion test was performed on "normal" subjects (n = 12) and subjects with BHT (n = 10). Dose-response relation was obtained in terms of various doses of ISO and the increments of heart rate (deltaHR) produced by ISO. In the latter half of this study, phenylephrine (PHE) infusion test was carried out in the series of "normal" subjects (n = 5) and subjects with BHT (n = 6), a partly different series from the first series of subjects. Dose-response relation, again, was obtained in terms of various doses of PHE and the increments of total peripheral resistance (deltaTPR) produced by PHE. These relations were displayed on Lineweaver-Burk's plot and the "affinity" of ISO to cardiac chronotropic beta-receptor or that of PHE to vasoconstrictive alpha-receptor of skeletal muscle resistance vessels was estimated, graphically, assuming that 1) drugs were diluted by a volume of body fluid equal to the blood volume which was actually measured in each individual and 2) this concentration of drugs existed around the receptor site, i.e., there was no significant individual variations in terms of the metabolism and the distribution of the drugs. Estimated "affinity" of ISO to cardiac chronotropic beta-receptor was 0.168 +/- 0.014 x 10(4) ml X ug-1 (mean +/- SE, n = 10) in patients with BHT, while it was 0.170 +/- 0.015 x 10(4) (n = 12) in "normal" subjects. Estimated "affinity" of PHE to vasoconstrictive alpha-receptor of skeletal muscle resistance vessels was 0.171 +/- 0.011 x 10(2) ml X ug-1 (n = 6) in patients with BHT, while it was 0.183 +/- 0.012 x 10(2) (n = 5) in "normal" subjects. It is concluded from these data, almost fairly, that there is no difference in terms of the estimated "affinity" of ISO to cardiac chronotropic beta-receptor or that of PHE to vasoconstrictive alpha-receptor between "normal" subjects and patients with BHT. It was also found, in PHE infusion tests, that the plasma adrenaline concentration was significantly higher in patients with BHT than in "normal" subjects, at least at two points of time in the test: a) immediately before PHE infusion, when every individual appeared to be considerably restful and b) at the end of 1-2 min after the completion of the infusion of the largest dose of PHE used.