CONTEXT: Before the development of human colonic neoplasms, colonic epithelial cells showed altered growth and differentiation. These alterations characterized mucosa at risk for cancer formation and were termed intermediate biomarkers of risk. Modifications of the mucosa toward more normal features by nutrients or drugs are putative approaches to chemoprevention of colon cancer. OBJECTIVE: To determine whether increasing calcium intake via dairy products alters colonic biomarkers toward normal. DESIGN: Randomized, single-blind, controlled study. SETTING: Outpatient clinic. PARTICIPANTS: Seventy subjects with a history of polypectomy for colonic adenomatous polyps. INTERVENTION: Low-fat dairy products containing up to 1200 mg/d of calcium. Subjects were randomized to 4 strata by diet (control vs higher calcium) and age (<60 vs > or = 60 years). MAIN OUTCOME MEASURES: Changes in total colonic epithelial cells and number and position of thymidine-labeled epithelial cells and changes in the ratio of sulfomucins (predominantly secreted by distal colorectal epithelial cells) to sialomucins and expression of cytokeratin AE1, 2 markers of colonic cell differentiation. RESULTS: During 6 and 12 months of treatment, reduction of colonic epithelial cell proliferative activity (P<.05), reduction in size of the proliferative compartment (P<.05), and restoration of acidic mucin (P<.02), cytokeratin AE1 distribution (P<.05), and nuclear size (P<.05) toward that of normal cells occurred. Control subjects showed no differences from baseline proliferative values at 6 and 12 months (P>.05). CONCLUSION: Increasing the daily intake of calcium by up to 1200 mg via low-fat dairy food in subjects at risk for colonic neoplasia reduces proliferative activity of colonic epithelial cells and restores markers of normal cellular differentiation.

Adenomatous Polyposis Coli↗

PubMedDate not supplied

A mechanism for anomalous decline in radon precursory to an earthquake.

Mechanisms for interpreting anomalous decreases in radon in ground water prior to earthquakes are examined with the help of a case study to show that radon potentially is a sensitive tracer of strain changes in the crust preceding an earthquake. The 2003 Chengkung earthquake of magnitude (M) 6.8 on December 10, 2003, was the strongest earthquake near the Chengkung area in eastern Taiwan since 1951. The Antung radon-monitoring station was located 20 km from the epicenter. Approximately 65 d prior to the 2003 Chengkung earthquake, precursory changes in radon concentration in ground water were observed. Specifically, radon decreased from a background level of 780 pCi/L to a minimum of 330 pCi/L. The Antung hot spring is situated in a fractured block of tuffaceous sandstone surrounded by ductile mudstone. Given these geological conditions, we hypothesized that the dilation of brittle rock mass occurred at a rate faster than the recharge of pore water and gas saturation developed in newly created cracks preceding the earthquake. Radon partitioning into the gas phase may explain the anomalous decrease of radon precursory to the 2003 Chengkung earthquake. To support the hypothesis, vapor-liquid, two-phase radon-partitioning experiments were conducted at formation temperature (60 degrees C) using formation brine from the Antung hot spring. Experimental data indicated that the decrease in radon required a gas saturation of 10% developed in rock cracks. The observed decline in radon can be correlated with the increase in gas saturation and then with the volumetric strain change for a given fracture porosity.

Disasters↗

PubMedDate not supplied

Tongue base minor salivary gland tumor: report of a case with mucoepidermoid and acinous cell components.

A case of a large (5.5 cm), multilobulated, mucosa-covered, minor salivary gland tumor of the base of the tongue that displayed morphologic features of both a mucoepidermoid carcinoma and an acinous cell tumor is described. Generally, each of these salivary gland tumors occurs only rarely at this site. A tumor with both these elements has not previously been reported.

Carcinoma↗

PubMedDate not supplied

Expression of multidrug resistance-related markers in gastric cancer.

BACKGROUND: To detect the expression of glutathione S-transferase Pi(GST-pi), multidrug resistance-associated protein (MRP), lung-resistance protein(LRP), multidrug resistance gene1 (MDR1) and MGr1 antigen(MGr1-Ag) in the patients with primary gastric cancer and without any prior chemotherapy and to evaluate the correlations between them. PATIENTS AND METHODS: The expression of GST-pi, MRP, LRP and MDR1 in cancer tissue and the adjacent non-cancerous tissue from 50 patients was examined by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). The expression of MGr1-Ag in these tissues was also examined by immunohistochemistry. RESULTS: The positive rate of GST-pi mRNA, MRP mRNA, LRP mRNA, MDR1mRNA and MGr1-Ag in gastric cancer tissue was 36.00%, 12.00%, 10.00%, 10.00% and 18.00% respectively. The overall positive rate of their expression was 58.00%. Clinicopathological factors were not significantly related to their expression. No significant correlation was observed between these markers. CONCLUSION: These MDR markers are differently over-expressed and no coexpression exists in gastric cancer. MGr1-Ag was a novel MDR protein.

ATP Binding Cassette Transporter, Subfamily B, Mem↗