Chronic liver inflammation and hepatic regeneration by infection with hepatitis B (HBV) or C virus (HBC) seem to be important risk factors for hepatocellular carcinoma (HCC). Regarding the hepatocarcinogenesis of HBV DNA integration, it has been variously hypothesized that mechanisms such as the alteration of host chromosomal DNA and transcriptional trans-acting activity of the X gene are activated. On the other hand, integration of HCV virus into chromosomal DNA has not been reported. It is suggested that HCV could replicate more efficiently in noncancerous than in cancerous tissues. Therefore, it might affect some oncogenes or cause an inactivation of tumor suppressor genes in the early stage of HCC. Genetic alterations such as a point mutation and loss of heterozygosity are considered to be late events occurring after tumorigenesis. Regeneration of liver cells through chronic hepatitis increases the incidence of genetic alterations in hepatic cells and/or HCCs in both HBV- and HCV-infected patients.

Carcinoma, Hepatocellular↗

PubMedDate not supplied

Intra-aortic ultrasonography in advanced esophageal cancer.

Thirty-one advanced esophageal cancer patients underwent preoperative intra-aortic ultrasonography (IAUS), and aortic invasion was found in nine patients. In five patients, the aortic invasion was diagnosed as limited in the aortic adventitia, enabling the preoperative prediction of the tumors. The aortic invasion to all layers was visualized by IAUS in four cases. Intra-aortic ultrasonography provides important information to determine the resectability of advanced esophageal cancer.

Aorta, Thoracic↗

PubMedDate not supplied

Clinical application of K-ras oncogene mutations in pancreatic carcinoma: detection of micrometastases.

Pancreatic adenocarcinomas are known to have a high incidence of K-ras gene mutation. We summarize our efforts to detect micrometastases through a search for mutated K-ras oncogene in liver tissues, peritoneal washings, para-aortic lymph nodes, and perioperative peripheral blood. Two-stage polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis were used to detect K-ras oncogene mutations at codon 12. Our results suggest that PCR/RFLP analysis is potentially highly sensitive for the detection of micrometastases in various tissues and might be of value in the diagnosis, treatment and follow-up of metastases in other organs with pancreatic adenocarcinoma.

Adenocarcinoma↗

PubMedDate not supplied

Early diagnosis of leukoencephalopathy of acute lymphocytic leukemia by MRI.

Using repeated computed tomographic and magnetic resonance imaging scans, we examined 8 patients with acute lymphocytic leukemia during remission induction therapy between 1988 and 1989. In 3 patients, leukoencephalopathy was diagnosed by T2-weighted magnetic resonance imaging. In 1 patient, leukoencephalopathy was progressive and irreversible brain damage and mental retardation persisted. In the other 2 patients, hyperintense lesions in the periventricular white matter were transient and no neurologic sequelae ensued. Magnetic resonance imaging was more useful than computed tomography in the early diagnosis and management of these acute lymphocytic leukemia patients with leukoencephalopathy.

Antineoplastic Combined Chemotherapy Protocols↗

PubMedDate not supplied

Newly developed drug delivery system in cancer chemotherapy using direct electric current.

To improve the antitumor effect of chemotherapy on a target organ, we experimentally investigated pharmacokinetic alteration of methotrexate (MTX) induced by an electric current in rats to ascertain whether the local concentration of MTX could be enhanced while reducing the concentration in blood. Six male Wistar rats had platinum electrodes introduced into both kidneys. Three rats were subjected to direct current (3.5 V, 50 microA) for 3 hours, while another three control rats received no current. While providing the current to the treated group, all of the rats were intravenously injected with MTX at a dose of 1 mg/kg. The MTX concentration in urine (excreted from each ureter) and serum was measured by fluorescence polarization immunoassay. Cumulative MTX renal excretion rate was significantly higher in the cathode than anode side in the treated group (p < 0.01). Serum MTX concentration at 0 to 5 min was significantly reduced in the treated group (p < 0.03). The first part of the area under the curve (i.e., alpha curve) was markedly increased in the treated group versus controls (p = 0.05). Electric therapy using a slight direct current could gather anionized MTX to the cathode, while reducing MTX concentration in the serum of experimental rats.

Animals↗

PubMedDate not supplied

Attenuation of pressor responses to norepinephrine and pitressin and potentiation of pressor response to angiotensin II by captopril in human subjects.

The present study was conducted to investigate the influence of captopril on cardiochemodynamic responses in 38 normal volunteers (20- to 35-year-old men) to exogenously administered vasopressor substances. Norepinephrine (NE), 0.05, 0.1, and 0.2 micrograms/kg min-1; angiotensin II (AII), 5, 10, and 20 ng/kg min-1; and pitressin (2 mU/kg min-1) were infused for 10 minutes. Each infusion was reported twice, and the responses were reproducible. Captopril (50 mg by mouth) significantly attenuated the pressor responses to NE and pitressin, but the decrease in heart rate in response to NE and pitressin was almost the same before and after captopril treatment, suggesting that captopril potentiates reflex slowing of the heart. Captopril significantly potentiated the pressor response to AII. Attenuation of pressor response and potentiation of reflex slowing of the heart, in response to NE and pitressin, disappeared when a subdepressor dose of AII (1 ng/kg min-1) was infused in addition to captopril. Infusion of a subdepressor dose of bradykinin (BK), 0.1 microgram/kg min-1, had no influence on the pressor response to NE. In the subjects treated with indomethacin (225 mg/54 hrs), captopril still attenuated the pressor response to NE. These results suggest that captopril attenuates the pressor responses to NE and pitressin primarily by depletion of endogenous AII; decreased AII may desensitize the contraction of arterial smooth muscle and may potentiate the compensatory reflex mechanism.

Adult↗

PubMedDate not supplied

Polymorphism of tumor necrosis factor in esophageal, gastric or colorectal carcinoma.

BACKGROUND/AIMS: Several microsatellite polymorphisms located in the tumor necrosis factor locus on the chromosomal region 6p21.3 in the major histocompatibility complex region have been associated with malignant neoplasms and autoimmune diseases. In this study, we focused on the polymorphisms of tumor necrosis factor a and d from gastrointestinal carcinoma patients to ascertain whether they can be useful to predict these neoplasms. METHODOLOGY: We examined esophageal, gastric, and colorectal cancers (47, 53, 77 patients, respectively), and 213 normal controls. To compare the microsatellite polymorphisms of tumor necrosis factor a, d in Japanese individuals, dioxyribonucleic acids were extracted from normal mucosa (cancer patients) and from peripheral blood monocytes (the normal controls) by polymerase chain reaction. RESULTS: The frequency of tumor necrosis factor a3 allele was significantly higher in gastric cancer (P = 0.012) and that of tumor necrosis factor d7 allele was significantly higher in the colorectal cancer than the normal controls (P = 0.037). That of tumor necrosis factor a10 was significantly lower in the gastric cancer than the normal controls (P = 0.008). CONCLUSIONS: Microsatellite polymorphisms of tumor necrosis factor a and d might be significantly correlated with carcinogenesis of specific neoplasms, and may be useful for predicting these cancers.

Alleles↗