Effect of trihalomethanes on cell proliferation and DNA methylation in female B6C3F1 mouse liver

Trihalomethanes (chloroform, bromodichloromethane, chlorodibromomethane, and bromoform) are regulated organic contaminants in chlorinated drinking water. In female B6C3F1 mouse liver, the 4 trihalomethanes have demonstrated carcinogenic activity when administered by oral gavage; however, chloroform was not carcinogenic when administered in drinking water. Female B6C3F1 mice were administered the trihalomethanes for 11 days by gavage at 2 dose levels or in the drinking water at approximately 75% saturation. When administered by gavage, the trihalomethanes were toxic to the liver, increased the liver:body weight (bw) ratio, and increased the proliferating cell nuclear antigen-labeling index (PCNA-LI). Chloroform and bromodichloromethane were the most toxic, and they increased the liver:bw ratio the most, while bromoform and chloroform increased the PCNA-LI the most. When administered in drinking water, the toxicity of the trihalomethanes was similar to their low gavage-dose. Furthermore, only chloroform significantly increased the liver:bw ratio and bromoform and chloroform increased the PCNA-LI. Chloroform and bromodichloromethane decreased the level of 5-methylcytosine in hepatic DNA. Methylation in the promoter region of the c-myc gene was reduced by the trihalomethanes. Chloroform administered by gavage was more efficacious than given in drinking water; the efficacy of the other trihalomethanes did not differ for the 2 routes. Thus, in mouse liver, the trihalomethanes administered by gavage enhanced cell proliferation and decreased the methylation of the c-myc gene, consistent with their carcinogenic activity. Furthermore, the more modest toxicity, enhancement of cell proliferation, and decreased methylation induced by chloroform administered in drinking water correlated with its lack of carcinogenic activity. Hence, the activity of the trihalomethanes was dependent on the rate of delivery, i.e. rapid by oral gavage and more slowly in drinking water.

[Paraneoplastic intestinal pseudo-obstruction revealing small cell lung carcinoma: "the anti-Hu syndrome"]

A 67-year-old woman was admitted for intestinal pseudoobstruction associated with peripheral sensitive neuropathy. Jejunal biopsies performed during laparotomy, showed axonal degeneration and lympho-plasmocytic infiltration in myenteric plexus. High titer of seric anti-Hu antibodies suggested a paraneoplastic syndrome. Thoracic CT scan showed mediastinal lymph nodes. Their histological examination confirmed the diagnosis of metastatic small-cell lung carcinoma. Her condition gradually deteriorated despite supportive parenteral nutrition, chemotherapy, steroids and intravenous immunoglobulins. She died 12 months after the onset of symptoms.

[Upper gastrointestinal haemorrhage in the patients aged over 65 years. The contribution of endoscopy (author's transl)]

One hundred and eighty four patients aged over 65 years and hospitalised for gastrointestinal haemorrhage of high origin underwent emergency oesophago-gastro-duodenoscopy. It was thereby possible to make an aetiological diagnosis in 94.5% of cases. The study demonstrated certain special features: the preponderance of acute gastro-duodenal lesions, possibly explained by the high consumption of gastrotoxic drugs in the elderly subject; the relative frequency of oesophagitis (11%), one out of two cases being responsible for the bleeding; the discovery of a hiatal hernia in 59 patients (1/3 of cases), 25% of them bleeding from a lesion directly related to the latter. Bleeding was in large quantity in 57% of cases. Mortality, which was quite high (17%) appeared to be more related to the underlying general condition than to the haemorrhage itself. Endoscopy gave rise to complications in 8 patients, including 3 who died.

[Endoscopic sphincterotomy. 362 cases (author's transl)]

In addition to its diagnostic value, endoscopic catheterisation of the papilla may be used for the therapeutic purpose of diathermy incision of the papilla and of the intraduodenal portion of the common bile duct. Endoscopic sphincterotomy of this type has been essentially used in choletithiasis and in particular for residual lithiasis. These indications may be widened to include benign stenosis of the sphincter of Oddi, tumours of the ampulla of Vater or even acute pancreatitis. In a total of 362 cases, sphincterotomy was successful in 347 patients, it being possible to remove the calculi present in 279 of the 309 patients treated with success for lithiasis of the common bile duct. Complications occur in approximately 10% of cases, being fatal in 1.4% of cases. These are essentially related to bleeding. Retrospective comparison of mortality after surgical operation and after endoscopic sphincterotomy is in favour of the latter, provided the technique employed is perfect and the indication clearly defined. Performed without general anaesthesia, endoscopic sphincterotomy is above all indicated in the elderly and/or those with other major pathology who can be successfully treated with reduced risk in 93% of cases, as shown by the 140 personal cases of the authors cured between 6 and 36 months ago.

Endoscopic retrograde cholangiopancreatography

Direct non-operative injection of radio-opaque material through a cannula introduced at the duodenal papilla by means of a fibre-optic duodenoscope achieved opacification of the bile ducts, the pancreatic duct or the entire biliary pancreatic ductal system in 392 (89 per cent) of 439 patients in whom it was attempted. The desired ducts were opacified in 75 per cent of cases; the bile ducts in 206 out of 278 and the pancreatic duct in 120 out of 161 cases. The anatomical conditions found were: long common biliary pancreatic channel, 30 per cent; short common biliary pancreatic channel, 28per cent; two orifices in the hepatopancreatic ampulla, 24 per cent; two orifices on the duodenal papilla, 18 per cent; two orifices on the duodenum, there being no papilla, less than I per cent. Morbidity resulting from the procedure consisted of infectious reactions in 20 out of 295 patients in whom the bile ducts were opacified and hyperamylasaemia and abdominal pain in 28 out of 300 patients in whom the pancreatic duct was opacified. The method is of value in diagnosing the cause of cholestatic jaundice. In non-jaundiced subjects it may complement or clarify inconclusive cholangiograms or cholecystograms obtained by other techniques. If it shows dilated bile ducts operation should not be delayed, otherwise there is a risk of cholangitis. Pancreatic carcinoma may be revealed by stenosis, partial or total, of the pancreatic duct or by filling defects in the pancreatic parenchyma. Both chronic pancreatitis and pancreatic carcinoma may cause partial stenosis of the pancreatic duct. A filiform appearance of the pancreatic duct suggests chronic pancreatitis.