Malignant transformation of HPV 16-immortalized human endocervical cells by cigarette smoke condensate and characterization of multistage carcinogenesis

A number of epidemiological studies indicate that cigarette smokers are at increased risk of developing cervical cancer. However, convincing biological evidence is lacking. This report examines the biological and cellular role of human papillomavirus (HPV) type 16 and cigarette smoke in multistage cervical carcinogenesis. Two lines of HPV 16-immortalized human endocervical cells (HEN-16 and HEN-16-2) generated from primary cells (HEN) were treated with cigarette smoke condensate (CSC). CSC-treated, but not untreated, HEN-16 and HEN-16-2 formed tumors that were invasive squamous cell carcinomas in nude mice. The tumors were used to initiate 2 tumor lines of cells (HEN-16T and HEN-16-2T, respectively). Cells of both tumor lines, compared with HEN, HEN-16 and HEN-16-2, featured: (a) tumorigenicity, (b) distinct morphologies in monolayer and organotypic (raft) cultures, (c) faster growth in serum plus high calcium levels after immortalization and after transformation, (d) higher saturation density and (e) anchorage-independent growth. Our results provide unique direct in vitro evidence that cigarette smoke causes cancer in HPV-containing cervices.

Resistance to retinoic acid and altered cytokeratin expression of human papillomavirus type 16-immortalized endocervical cells after tumorigenesis

Human papillomaviruses (HPVs) and cigarette smoking are epidemiologically associated with cervical cancer. We recently found that HEN-16 and HEN-16-2 HPV type 16-immortalized endocervical cells form tumors after treatment with cigarette smoke condensate and derived 2 tumor cell line cultures, HEN-16T and HEN-16-2T, respectively. Here, we examine the molecular pathologic effect of tumorigenesis. HEN-16T and HEN-16-2T exhibit unchanged status and expression of integrated HPV 16 DNA. However, the expression of the cytokeratin CK7 and CK13 endocervical cell markers is more homogeneous in monolayer and organotypic raft cultures after tumorigenesis. For the effect of retinoic acid on monolayers for growth inhibition, HEN-16T were significantly less sensitive than the normal and immortalized non-tumorigenic cells. HEN-16-2T were completely resistant. Moreover, the rafts from both tumorigenic cell line cultures were resistant to retinoic acid and continued to display thick rafts and homogeneous severe dysplasia/carcinoma in situ. In contrast, the non-malignant HEN-16 and HEN-16-2 rafts were thinner, and treatment with retinoic acid blocked the formation of severe dysplasia, reconstructing an epithelium resembling that of the normal endocervix. Our results support the significance of non-viral factors in the mechanism by which cigarette smoking induces tumorigenesis in the late stages of HPV-initiated progression to cervical cancer. Importantly, our data indicate that the sensitivity to retinoic acid of the HPV-containing endocervical cells is lost following tumorigenesis in vitro and possibly in women.

Transcriptional regulation of hydroxypyruvate reductase gene expression by cytokinin in etiolated pumpkin cotyledons

To understand the mechanisms by which the expression of a specific gene is modulated by cytokinin, the regulation of hydroxypyruvate reductase (HPR) transcript levels by N6-benzyladenine (BA) in etiolated pumpkin (Cucurbita pepo L. cv. Halloween) cotyledons was investigated. A pumpkin HPR cDNA was generated by reverse transcriptase-polymerase chain reaction and its nucleotide sequence was determined. An antisense HPR RNA was prepared for RNase protection analysis of HPR-mRNA expression patterns in the cotyledons of dark-grown pumpkin seedlings. Treatment of the cotyledons with BA was shown to modulate HPR mRNA levels in a dose- and time-dependent manner. Similarly, nuclear run-on studies showed that the rate of transcription was also enhanced by BA treatment of the cotyledons. These results suggest that the enhancement of HPR mRNA by cytokinin is, at least in part, at the level of transcription.

A biosensor concept based on imaging ellipsometry for visualization of biomolecular interactions

A new type of optical biosensor system is proposed and its application to detection of antigen-antibody complexes on a silicon substrate is demonstrated. The biosensor system is utilizing specificities of biomolecular interactions in combination with protein patterned surfaces. Visualization of the thickness distributions of thin layers (protein patterns) on a surface is achieved by using imaging ellipsometry. This technique uses a CCD camera whereby an ellipsometric analysis of a large surface can be made. The biosensor system has the advantages of high spatial resolution, fast data acquisition, and simplicity in use.

Glucagon, stress, and portal hypertension. Plasma glucagon levels and portal hypertension in relation to anesthesia and surgical stress

Glucagon has been proposed as the mediator of splanchnic hyperemia in portal hypertension. Employing an assay specific for pancreatic glucagon, we reevaluated the relationship between this peptide and portal hypertension in the portal vein (PV)-stenosed rat model addressing, in particular, the effects of anesthesia and surgical stress. Plasma glucagon levels were similar in sham-operated and portal hypertensive rats: glucagon, sham vs PV stenosed: 110.7 +/- 17.1 pmol/liter vs 140.6 +/- 23.3 pmol/liter (NS). Furthermore, plasma levels of glucagon and the related peptide VIP were not significantly influenced by anesthesia or surgical stress, and levels remained similar under all conditions in sham-operated and PV-stenosed animals. We conclude that pancreatic glucagon is not elevated in the PV-stenosed rat; differences between these results and those describing hyperglucagonemia in this model cannot be explained on the basis of a differential response to stress but may reflect differences in glucagon assay system.

Emergency shunt. Role in the present management of variceal bleeding

OBJECTIVE

To evaluate the results of selective and nonselective emergency portosystemic shunts in patients with acute variceal hemorrhage.

DESIGN

Retrospective review.

SETTING

University medical center and Veterans Affairs medical center.

PATIENTS

Forty-two consecutive patients who underwent emergency portosystemic shunts from 1978 through 1994. All patients had chronic liver disease (29 [69%] had alcoholic cirrhosis) and half had Child's class C disease. Sixteen patients were actively bleeding at the time of surgery, and 26 had bled within 48 hours. Twenty-two patients underwent a nonselective shunt and 20 underwent a distal splenorenal shunt. The percentages of patients with Child's class C disease and with active bleeding at the time of surgery were significantly higher in the nonselective shunt group.

MAIN OUTCOME MEASURES

Operative mortality; early postoperative rebleeding, shunt patency, encephalopathy, and ascites; and long-term survival.

RESULTS

Operative mortality rates were higher in patients with Child's class C disease (43% [9/21]) than in patients with Child's class A or B disease (9% [2/21]) and were higher in patients with active bleeding (all of whom underwent nonselective shunt) (44% [7/16]) than in patients who underwent distal splenorenal shunt (10% [2/20]). All shunts were patent after surgery, and no patient had rebleeding during the early postoperative interval. Early postoperative ascites and encephalopathy rates were similar after nonselective shunt and distal splenorenal shunt. Long-term survival was superior in the lower-risk distal splenorenal shunt group.

CONCLUSIONS

Even though more effective nonoperative treatments are now available, emergency portosystemic shunt remains an important option for selected patients with acute variceal hemorrhage. When bleeding can be temporarily controlled by nonoperative means, distal splenorenal shunt is an effective and safe emergency procedure. The mortality rate remains high for patients with Child's class C disease undergoing protal decompression.

A non-invasive method for evaluating cirrhotic portal hypertension by administration of 99mTc-MIBI per rectum

A study was performed to evaluate radio-isotopic imaging using technetium-99m hexakis 2-methoxyisobutyl isonitrile administered per rectum to assess portal collateral circulation. The heart-liver ratios (H/L; mean +/- standard deviation) in 15 controls, 13 cases of histologically confirmed viral hepatitis and 57 cirrhosis patients were 0.27 +/- 0.11, 0.43 +/- 0.14 and 1.00 +/- 0.28, respectively (P < 0.001). Among the cirrhosis patients those with the Child-Pugh classification A, B and C had H/L of 0.56 +/- 0.14, 1.00 +/- 0.20 and 1.19 +/- 0.26, respectively (P < 0.001). A high value of H/L was associated with a high risk of hepatic encephalopathy (1.25 +/- 0.17, P < 0.01) and oesophageal varices (1.02 +/- 0.20, P < 0.01). There were associations between H/L and serum bilirubin (P < 0.01), albumin (P < 0.05) and prothrombin time (P < 0.05). The results also showed a good correlation between H/L and portal vein pressure measured during operation in 13 patients (P < 0.001, r = 0.87). The regression equation: y = 6.77 + 32.5 H/L, allowed portal vein pressure to be estimated. The prognostic value of the test was supported by the fact that good correlations were observed between the H/L ratio and widely accepted prognostic classification (Child-Pugh). It is suggested that this new method could be a reliable non-invasive way to give an indication of the degree of portasystemic shunting to evaluate the prognosis and to follow up the effects of medications for reducing portal hypertension in patients with cirrhotic portal hypertension.

Joint wavelet-transform correlator for image feature extraction

We describe a joint wavelet-transform correlator in which the wavelet function is combined with the input image as the input joint image to realize the wavelet transform of the objective image. The Haar wavelet and the Roberts filter are chosen as the wavelet functions to extract the features of the objective image. The relationship of the Haar wavelet and the Roberts filter is analyzed mathematically based on admissible condition of the wavelet. Computer simulations are provided to verify the theory and to illustrate the performance of this correlator.

Pancreatic complications after distal splenorenal shunt

Pancreatic complications after the distal splenorenal shunt have not been commonly recognized. Between January 1978 and June 1993, 154 patients underwent a distal splenorenal shunt, and 11 patients (7%) developed pancreatic complications, of which 4 had pancreatitis alone, and 7 developed pancreatitis-related complications. Etiology of cirrhosis, Child's classification and timing of surgery were not predictive of pancreatic complications. Eight patients (5%) were found to have chronic pancreatitis at the time of surgery, and four of these patients (50%) developed pancreatic complications following distal splenorenal shunt. Eleven early postoperative deaths in our series resulted in an overall operative mortality rate of 7%. Of these eleven patients, 6 (55%) had postoperative pancreatic complications. The operative mortality rate of patients who developed pancreatic complications (55%) after distal splenorenal shunt was significantly greater than that of patients who did not develop pancreatic complications (3%), P < .001. When compared with patients without pancreatitis, those with pancreatitis had significantly greater incidences of complete or partial portal vein thrombosis (55% v 20%, P < .02), severe ascites (64% v 13%, P < .001), and encephalopathy (45% v 3%, P < .001). We reach the following conclusions: (1) although not a frequent complication after distal splenorenal shunt in general, pancreatitis was commonly present in early postoperative deaths and was most likely a major contributor to the demise of those patients; (2) survivors with postdistal splenorenal shunt pancreatitis had a markedly increased morbidity rate; and (3) pancreatic complications after distal splenorenal shunt are more likely to occur in patients with pre-existing chronic pancreatitis.

Comparative effects of intraduodenal psyllium and senna on canine small bowel motility

BACKGROUND/AIM

To define the possible contribution of altered small intestinal motor activity to side-effects of bulking fibres, we sought to compare the relative effects of intraduodenal and intracolonic administration of the bulking fibre psyllium and the anthraquinone laxative senna on canine small intestinal motor activity.

METHODS

Motor activity was recorded by serosal strain gauges implanted along the small intestine in 6 dogs. In random order, the motor responses to the instillation of psyllium (in doses of 5 or 10 g), senna (10 mg/kg) or appropriate vehicle (200 ml water infusion or saline 5 ml bolus) into either the proximal duodenum or proximal colon were assessed.

RESULTS

The intra-duodenal administration of psyllium in either dose consistently induced a prolonged burst of 'clustered' contractions; in contrast, clusters were infrequent and of short duration following instillation of either vehicle or senna (P < 0.05). Intraduodenal instillation of psyllium inhibited migrating motor complex (MMC) migration and consistently delayed the onset of the next MMC cycle; a similar inhibition occurred with vehicle, however. Neither senna nor its vehicle inhibited MMC migration. None of these agents had any effect on small intestinal motor activity when instilled directly into the colon.

CONCLUSIONS

Psyllium administered directly into the duodenum inhibits MMC activity and consistently induces 'clustered' contractions. Whilst the MMC-inhibitory effect appears to be a non-specific volume-related phenomenon, the induction of clusters is independent of volume or laxation. These motor effects of psyllium may contribute to the gastrointestinal symptomatology related to such agents and could be avoided by the preferential release of psyllium in the colon.

Surgical management of acute variceal hemorrhage

The advent of more effective nonoperative therapies, mainly endoscopic variceal sclerosis, has decreased the need for emergency surgery for control of acute variceal hemorrhage. In centers where it is available, nonoperative portal decompression by transjugular intrahepatic portosystemic shunting (TIPS) is likely to have a further impact. When acute or chronic sclerotherapy fails or when bleeding is secondary to gastric varices or portal hypertensive gastropathy, emergency surgery may be life-saving and should be done promptly before worsening hepatic functional decompensation develops. Child's class C liver disease is not a contraindication to emergency surgery; many patients who fail nonoperative attempts at control of bleeding are of this risk status. The most commonly utilized emergency procedures are portacaval and interposition mesocaval shunts, both of which are effective, and esophageal transection, which is associated with a higher incidence of late rebleeding. An emergency distal splenorenal shunt is appropriate for selected patients who are not actively bleeding at the time of surgery. TIPS is the preferred alternative for acute or chronic endoscopic sclerotherapy failures who are candidates for liver transplantation within the succeeding 6 to 12 months.

Variceal hemorrhage: surgical therapy

Surgical options for management of variceal hemorrhage include portosystemic shunts (nonselective and selective), nonshunting operations, and hepatic transplantation. In most centers, operations that preserve hepatic portal perfusion (selective shunt and nonshunting operations) have replaced nonselective shunts as the most commonly performed surgical procedures. The results of multiple controlled trials suggest that the frequency of postshunt encephalopathy is less after the distal splenorenal shunt than after the nonselective shunts. Hepatic transplantation should be considered as initial therapy for nonalcoholic cirrhotics and abstinent alcoholic cirrhotics with variceal hemorrhage or advanced liver disease and without contraindications.

Bacterial translocation in the portal-hypertensive rat: studies in basal conditions and on exposure to hemorrhagic shock

BACKGROUND

Portal hypertension is associated with altered intestinal motor and mucosal function. The aim of this study was to determine whether portal hypertension, per se, or in association with acute hemorrhagic shock, predisposes to the translocation of bacteria across the intestine.

METHODS

Translocation to both mesenteric lymph nodes and blood was compared in three groups of rats: portal-hypertensive (single-stage calibrated stenosis of portal vein), sham-operated, and unoperated controls. Half of the animals in each group were exposed to hemorrhagic shock.

RESULTS

In the basal state, translocation to both mesenteric lymph nodes (portal hypertension vs. sham vs. controls, 411.5 +/- 119 vs. 151.1 +/- 42.6 vs. 18.1 +/- 12.6 colony-forming units [CFU]/g; P < 0.05) and blood (portal hypertension vs. sham vs. controls, 100% vs. 30% vs. 0% positive blood cultures; P < 0.05) was significantly increased in the portal-hypertensive animals. Furthermore, translocation was strikingly increased in these animals after hemorrhagic shock (mesenteric lymph node cultures, portal hypertension vs. portal hypertension with shock, 411 +/- 119 vs. 1018.2 +/- 372.2 CFU/g; P < 0.05).

CONCLUSIONS

Portal hypertension promotes bacterial translocation, especially in relationship to acute hemorrhage. These findings may, in part, explain the susceptibility of patients with liver disease to sepsis of enteric origin.

Shunt surgery versus endoscopic sclerotherapy for variceal hemorrhage: late results of a randomized trial

Between September 1982 and April 1988, 60 cirrhotic patients with prior variceal hemorrhage were randomized to undergo the placement of an elective shunt (distal splenorenal: 26; nonselective: 4) or long-term endoscopic sclerotherapy (n = 30). Eighty-six percent of patients had alcoholic cirrhosis, and 33% were classified as Child's class C. After a mean follow-up of 87 months, 60% of patients undergoing sclerotherapy and 17% of shunt patients experienced rebleeding (p < 0.001). Shunt patients have survived longer than those who had sclerotherapy (6-year survival rates of 53% and 26%, respectively; p < 0.05). In part because of the wide geographic distribution of patients, only 4 of 13 patients in whom sclerotherapy failed (31%) could undergo salvage by shunt surgery. Although hepatic portal perfusion was better maintained after sclerotherapy, there were no major differences between the groups in terms of post-therapy hepatic or psychoneurologic function. In a predominantly alcoholic cirrhotic patient population (half non-urban), the results of elective shunt surgery were superior to those of chronic endoscopic sclerotherapy with respect to the prevention of recurrent variceal hemorrhage and survival.

Measurements of magnetic fields by a ring laser

The principle of measuring magnetic fields with a ring laser system is discussed. The main source of error, the Zeeman effect, is studied, and a corresponding technique to reduce it is described. An experimental setup is developed with a Faraday cell of a large product of the Verdet constant and the length. The experimental device obtains a sensitivity of 0.5 nT and a stability of 2 nT.

Cause and management of upper gastrointestinal bleeding after distal splenorenal shunt

BACKGROUND

The aims of this study were to determine the causes of recurrent upper gastrointestinal hemorrhage (UGH) after distal splenorenal shunting (DSRS) and to summarize our experience in the prevention and management of this complication.

METHODS

This study is based on a retrospective review of 145 consecutive patients undergoing DSRS from 1978 through 1991.

RESULTS

Recurrent UGH developed in 19 patients (13%), most frequently secondary to residual portal hypertension (84%). Eight patients had shunt thrombosis and 11 had patent shunts. The incidence of shunt thrombosis was significantly greater in patients whose splenic vein was less than or equal to 8 mm in diameter (44%) than those whose splenic vein was greater than 8 mm (7%, p less than 0.001). The frequency of shunt failure from 1985 through 1991 was significantly lower (2%) than from 1978 through 1984 (10%, p less than 0.05). Five patients, all with occluded shunts, underwent surgical treatment for recurrent UGH and three died (60%). Fourteen patients were managed nonoperatively, with a mortality rate of 38%.

CONCLUSIONS

Recurrent UGH after DSRS occurs in patients with patent shunts and in those with occluded shunts; DSRS thrombosis is more frequent when the splenic vein diameter is less than or equal to 8 mm; DSRS thrombosis decreases with operative experience; and the mortality rate for this complication is high with both operative and nonoperative management.

[Inhibitory effects of neferine and tetrandrine on portal vein and papillary muscle in rats]

To determine the vascular selectivity, the inhibitory effects of verapamil (Ver), neferine (Nef), and tetrandrine (Tet) on the spontaneous contractile force of portal vein and contractile force of the paced papillary muscle of left ventricle were studied in Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR). The vascular selectivity was expressed by the IC50 ratio (IC50 for papillary muscle/IC50 for portal vein). The results showed that the vascular selectivity values of Ver, Nef, and Tet were 1.15, 0.32, and 0.20, respectively in WKY and 0.80, 0.24, and 0.10, respectively in SHR. It is concluded that Nef and Tet, in contrast with Ver which is devoid of selectivity for either tissue, are more liable to inhibit the myocardium than the vascular smooth muscle. In addition, the IC50 value of Tet for inhibition of the portal vein in SHR was nearly 10-fold higher than that in WKY (237 and 27 mumol.L-1, respectively). This indicates that the response of portal vein to Tet is decreased in SHR.

Which portosystemic shunt is best?

No single shunt operation is ideal for all patients or all circumstances. The selective distal splenorenal shunt is preferred for the majority of patients, because it has the potential to preserve hepatic portal perfusion. Most evidence suggests that the distal splenorenal shunt is followed by a lower frequency of encephalopathy than is any type of nonselective shunt. Although theoretically attractive, the small-diameter interposition portacaval shunt has not yet been subjected to the scrutiny of controlled trials.

[Chemical constituents of Ledebouriella seseloides Wolff]

Eleven compounds were isolated from the methanolic extraction of the radix of Ledebouriella seseloides. They were identified as beta-sitosterol, bergapten, hamaudol, daucosterine sec-O-glucosylhamaudol, 5-O-methylvisamminol, cimifugin, sucrose, 4-O-beta-glucopyranosyl-5-O-methyl-visamminol, prim-O-glucosylcimifugin and mannitol by physico-chemical constants and spectroscopic analysis.

[Effect of radix Astragalus on the contents of collagen in the aorta and lung of old rats]

The result of experiments shows that the collagen contents in the aorta and lung of old rats are higher than in those of young rats, whereas the contents in the old rats given Radix Astragalus appear lower than those in the control group, close to those in young rats.

Reflection Zernike phase contrast microscope

A novel configuration for a reflection Zernike phase contrast microscope is given that has a height sensitivity of 0.5 A.

Birefringent tuning double frequency He-Ne laser

Experimental details are given of a novel, promising kind of double frequency laser-with power output of 0.8-1.4 mW, large frequency difference from 37 MHz to a longitudinal mode interval, and frequency stability of 10(-5), and its potential uses are discussed.