Evidence for regulation of transcription and replication of the human neurotropic virus JCV genome by the human S(mu)bp-2 protein in glial cells

Glial factor 1 (GF-1) is a partial cDNA isolated from a human brain cDNA library which encodes a truncated protein with binding ability to the B-regulatory domain of the human neurotropic virus, JCV. GF-1 exhibits sequence homology to the central region of the newly identified human DNA-binding protein S(mu)bp-2. GF-1 appears to be a partial cDNA for human S(mu)bp-2 based on its sequence homology to S(mu)bp-2 and their chromosomal co-localization. In this report, we have employed transfection assay and have compared the ability of GF-1 and its full-length form, S(mu)bp-2, on regulating the activity of JCV promoters in glial cells. Our results demonstrate that, unlike GF-1 which stimulates JCV early promoter in glial cells, overexpression of S(mu)bp-2 exhibits no drastic effect on the transcription of the viral early promoter. The activity of the viral late promoter was noticeably increased by both GF-1 and S(mu)bp-2, although the level of induction by GF-1 was consistently higher than that detected by S(mu)bp-2. Use of deletion constructs in co-transfection assay revealed that the B-domain of the JCV promoter is required for transcriptional activation by GF-1 and S(mu)bp-2. Expression of GF-1 and S(mu)bp-2 in glial cells increased the induced level of JCV late gene transcription by the viral early protein, T-antigen. Examination of the viral DNA replication by DpnI assay indicated that, unlike GF-1, S(mu)bp-2 has the ability to decrease the level of JCV DNA replication in glial cells. These observations suggest that the N-terminal portion of S(mu)bp-2 which encompasses several helicase motifs and/or its C-terminus, both of which are missing in GF-1, may confer differential effects on viral gene transcription and replication. The biological importance of our findings in regulation of the JCV lytic cycle in glial cells is discussed.

When to discharge patients with bleeding peptic ulcers: a prospective study of residual risk of rebleeding

BACKGROUND

From January 1993 to December 1994, we conducted a prospective study to investigate the evolutionary change of rebleeding risk in bleeding peptic ulcers. To obviate possible confounding factors that would influence decision making for discharge of patients, subjects with coexistent acute illnesses, systemic bleeding disorders, alcoholism, and use of nonsteroidal anti-inflammatory drugs were excluded.

METHODS

Emergency endoscopies were performed in patients with hematemesis or a melena within 24 hours of admission. Ulcer lesions were divided into six categories according to endoscopic findings. The residual risks of rebleeding of each type of ulcers were calculated for 10 days, and the critical point of acceptable rebleeding risk after discharge was set at 3%.

RESULTS

Three hundred ninety-two patients with bleeding peptic ulcers completed the study. The ulcers, characterized by clean bases, red or black spots, adherent clots, nonbleeding visible vessels without local therapy, nonbleeding visible vessels with local therapy, and bleeding visible vessels with local therapy took 0, 3, 3, 4, 4, and 3 days, respectively, to decrease rebleeding risk to below the critical point. All episodes of fatal rebleeding (n = 4) occurred within 24 hours after admission.

CONCLUSIONS

Patients with clean-based ulcers can be discharged in the first day of admission. The optimal duration required for hospitalization of patients with ulcers characterized by nonbleeding visible vessels at initial endoscopy is 4 days. The remaining patients with ulcers marked by other bleeding stigmata may be discharged after a 3-day observation.

Identification of a locus involved in the utilization of iron by Actinobacillus pleuropneumoniae

The cloned afu locus of Actinobacillus pleuropneumoniae restored the ability of an Escherichia coli K-12 mutant (aroB) to grow on iron-limited media. DNA sequence analysis of the fragment showed that there are three genes designated afuA, afuB and afuC (Actinobacillus ferric uptake) that encode products similar to the SfuABC proteins of Serratia marcescens, the HitABC proteins of Haemophilus influenzae, the FbpABC proteins of Neisseria gonorrhoeae and the YfuABC proteins of Yersinia enterocolitica. The three genes encode a periplasmic iron-binding protein (AfuA), a highly hydrophobic integral cytoplasmic membrane protein with two consensus permease motifs (AfuB) and one hydrophilic peripheral cytoplasmic membrane protein with Walker ATP-binding motifs (AfuC), respectively. This system has been shown to constitute a periplasmic binding protein-dependent iron transport system in these organisms. The afuABC operon is locating approximately 200 bp upstream of apxIC gene, but transcribed in opposite direction to the ApxI-toxin genes.

Factors influencing tumor cell kinetics in cervical cancer

Fresh tumor tissues instead of paraffin-embedded sections were used to study the clinical significance of the tumor cell kinetics in cervical carcinomas by flow cytometry. We analyzed specimens from 153 women with cervical cancer, and DNA aneuploidy was found in 61 cases (39.9%). The mean age of patients with aneuploid tumors was significantly higher than the age of patients with diploid tumors (P < 0.001). The mean proliferation index for aneuploid tumors was significantly higher than those for diploid tumors. There was a significant correlation between the proliferation index and age. However, tumor cell kinetics is not related to the status of human papillomavirus, herpes simplex virsuses I and II, lymph nodes, histology or tumor size. The mean age and S-phase fraction for stage-II tumors were significantly higher than those for stage-I tumors (P < 0.01). The tumors of menopausal patients exhibited a relatively higher rate of lymph node metastasis, and significantly higher aneuploidy rate and proliferation index than tumors of premenopausal patients. In summary, age and, what is more important, menopausal status may significantly influence DNA ploidy and cell kinetics of tumors, and subsequently influence clinical stage and lymph node metastasis. However, tumor cell kinetics is of limited value in the prediction of lymph node metastasis and prognosis.

Evidence that the soluble factors secreted by activated immune cells suppress replication of human neurotropic JC virus DNA in glial cells

Coordination of the immune response to viral infection and disease in the brain is believed to involve bidirectional interaction between the immune system and the central nervous system (CNS). Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the CNS that generally affects patients exhibiting an immunocompromised condition due to various illnesses. The human polyomavirus, JCV, which infects greater than 70% of the adult population is the etiological agent of this disease. Infection with JCV occurs during childhood and the virus remains in the latent state with no apparent clinical signals. However, under immunocompromised conditions, the virus enters the lytic cycle, and upon cytolytic destruction of glial cells, causes PML. To understand the molecular mechanism underlying immune regulation of JCV replication, we have developed a cell culture system and have investigated the effect of soluble factors from T-cell cultures on replication of JCV DNA in glial cells. Our data demonstrate that replication of JCV DNA in the presence of PMA-stimulated T-cell supernatant is substantially decreased in transfected glial cells. Heat-inactivation and size-fractionation studies revealed participation of a heat labile factor(s) which loses its maximum activity at 60 degrees and ranges between 30 and 100 kDa in size. The unfractionated T-cell supernatant and the fraction enriched in 30- to 100-kDa proteins reduced the level of viral DNA replication during the early phase of the lytic cycle. These observations suggest that regulatory factors which are secreted by immune cells may modulate the level of JCV DNA replication in glial cells. The importance of these observations in reactivation of JCV in immunocompromised individuals and development of PML is discussed.

Gallbladder function and recurrent stones of the biliary tract in patients after endoscopic sphincterotomy

BACKGROUND

Change in gallbladder function may occur in patients with an intact gallbladder after endoscopic sphincterotomy (EST). This study was designed to evaluate the factors influencing gallbladder filling after EST and the correlation between gallbladder function and stone recurrence.

METHODS

Sixty Chinese patients with symptomatic choledocholithiasis and an intact gallbladder received EST to clear the bile ducts. They were further investigated with sphincter of Oddi manometry (SOM), quantitative cholescintigraphy (QC), and long-term clinical follow-up.

RESULTS

Fifty-six of the 60 patients in the study group were confirmed to have a loss of sphincteric function by SOM. QC showed normal gallbladder filling in 35 of these patients and delayed or non-filling in 21 patients. A significantly higher incidence of normal gallbladder filling occurred in patients with juxtapapillary diverticulum than in those without (P < 0.02), but preexisting cholecystolithiasis had no effect on it. During the follow-up period (median, 32 months: range, 9-54 months) 10 of 56 patients developed recurrent choledocholithiasis. There was no correlation between the status of gallbladder filling, preexisting cholecystolithiasis, and recurrent stones, but 9 of the 10 patients with recurrent stones had a juxtapapillary diverticulum. Repeated endoscopic treatment was satisfactory in eight patients, and only two patients received cholecystectomy.

CONCLUSIONS

EST does not alter gallbladder function in most patients. Juxtapapillary diverticulum may facilitate gallbladder filling after EST, but it is also a possible factor for recurrent choledocholithiasis.

Evidence that replication of human neurotropic JC virus DNA in glial cells is regulated by the sequence-specific single-stranded DNA-binding protein Pur alpha

Initiation of polyomavirus DNA replication in eukaryotic cells requires the participation of the viral early protein T antigen, cellular replication factors, and DNA polymerases. The human polyomavirus JC virus (JCV) is the etiologic agent of the fatal demyelinating disease progressive multifocal leukoencephalopathy in immunocompromised individuals. This virus exhibits a narrow host range and a tissue specificity that restricts its replication to glial cells of the central nervous system. Restriction of viral DNA replication due to species specificity of the DNA polymerase, coupled with glial cell-specific transcription of the viral early promoter, is thought to account for the brain-specific replication of JCV. In this report we demonstrate that overexpression of Pur alpha, a protein which binds to single-stranded DNA in a sequence-specific manner, suppresses replication of JCV DNA in glial cells. Results from footprinting studies indicate that Pur alpha and T antigen share a common binding region spanning the single-stranded ori sequence of JCV. Further, T antigen was capable of stimulating the association of Pur alpha with the ori sequence in a band shift assay. Whereas no evidence for simultaneous binding of Pur alpha and T antigen to single-stranded DNA has been observed, results from coimmunoprecipitation and Western blot (immunoblot) analyses of proteins derived from cells producing JCV T antigen indicate a molecular association of JCV T antigen and Pur alpha. The binding of Pur alpha to the single-stranded ori sequence and its association with T antigen suggest that Pur alpha interferes with the activity of T antigen and/or other regulatory proteins to exert its negative effect on JCV DNA replication. The importance of these findings in the reactivation of JCV in the latently infected individual under immunosuppressed conditions is discussed.

Establishment and characterization of a human-papillomavirus negative, p53-mutation negative human cervical cancer cell line

A human cervical cancer cell line, CX, was established from a patient with squamous cell carcinoma of the uterine cervix. The CX cells were epithelial in morphology with relatively large vesicular nuclei, and prominent nucleoli. Cytoplasmic organelles were generally sparse but tonofilaments were relatively abundant. The cells grew as a compact sheet with close membrane approximation interconnected by desmosome-like junctions. CX cells contained cytokeratin, but not vimentin. Elevated levels of squamous cell carcinoma antigen and carcinoembryonic antigen were detected in the cell supernatants. Population doubling time was estimated to be about 20 h. CX cells were not able to grow in soft agar and not tumorigenic in nude mice. Chromosome analysis revealed that CX cells were heterogeneous and mainly had a female diploid karyotype. Unlike cervical cancer cell lines published previously, CX cells were demonstrated to be human papillomavirus-negative, p53 mutation-negative. Based on the distinct characteristics, CX cell line may prove to be a useful tool for the study of human cervical carcinogenesis.

The efficacy of endoscopic sphincterotomy in patients with sphincter of Oddi dysfunction

BACKGROUND

Dysfunction of the sphincter of Oddi (SOD) is one of the causes of postcholecystectomy syndrome and biliary pain. Endoscopic sphincterotomy (EST) is recommended in some patients refractory to conservative treatment. This study was designed to evaluate the efficacy of, and complications from EST in patients with SOD.

METHODS

Between 1990 and 1993, 24 patients clinically diagnosed as having papillary stenosis were treated by endoscopic sphincterotomy. All patients had dilated common bile duct (CBD) in addition to 1) elevation of transaminases and alkaline phosphatase (n = 13); 2) elevation of transaminases and serum amylase (n = 4); 3) normal liver enzymes but delayed biliary emptying on quantitative hepatobiliary scintigraphy (QHS) (n = 7). No CBD stones, organic obstruction or other disorders were found in these patients.

RESULTS

EST was successfully performed in 24 patients. One patient had minor hemorrhage and one patient developed pancreatitis after EST. Twenty-two of the 24 patients (91.7%) were symptomatically improved before discharge. Twenty-one patients were regularly followed over a median period of 18 months (range 5-36) after EST. Two patients with symptom had recurrence at five and eight month follow up because of restenosis of papilla; another two patients with recurrent biliary symptoms, but the sphincter of Oddi remained wide open. Seventeen of 21 regularly followed patients were symptom free after the median 18-month follow up.

CONCLUSIONS

EST is an effective and safe modality for treatment of sphincter of Oddi dysfunction.

Altered structural and mechanistic properties of mutant dihydropteridine reductases

Nine single genetic mutants of rat dihydropteridine reductase (EC 1.6.99.7), D37I, W86I, Y146F, Y146H, K150Q, K150I, K150M, N186A, and A133S and one double mutant, Y146F/K150Q, have been engineered, overexpressed in Escherichia coli and their proteins purified. Of these, five, W86I, Y146F, Y146H, Y146F/K150Q, and A133S, have been crystallized and structurally characterized. Kinetic constants for each of the mutant enzyme forms, except N186A, which was too unstable to isolate in a homogeneous form, have been derived and in the five instances where structures are available the altered activities have been interpreted by correlation with these structures. It is readily apparent that specific interactions of the apoenzyme with the cofactor, NADH, are vital to the integrity of the total protein tertiary structure and that the generation of the active site requires bound cofactor in addition to a suitably placed W86. Thus when the three major centers for hydrogen bonding to the cofactor are mutated, i.e. 37, 150, and 186, an unstable partially active enzyme is formed. It is also apparent that tyrosine 146 is vital to the activity of the enzyme, as the Y146F mutant is almost inactive having only 1.1% of wild-type activity. However, when an additional mutation, K150Q, is made, the rearrangement of water molecules in the vicinity of Lys150 is accompanied by the recovery of 50% of the wild-type activity. It is suggested that the involvement of a water molecule compensates for the loss of the tyrosyl hydroxyl group. The difference between tyrosine and histidine groups at 146 is seen in the comparably unfavorable geometry of hydrogen bonds exhibited by the latter to the substrate, reducing the activity to 15% of the wild type. The mutant A133S shows little alteration in activity; however, its hydroxyl substituent contributes to the active site by providing a possible additional proton sink. This is of little value to dihydropteridine reductase but may be significant in the sequentially analogous short chain dehydrogenases/reductases, where a serine is the amino acid of choice for this position.

Characterization of vitellogenin induced by estradiol-17β in protandrous black porgy,Acanthopagrus schlegeli

The objectives of this study were to isolate and characterize vitellogenin from plasma of estradiol-treated protandrous black porgy,Acanthopagrus schlegeli. Vitellogenin concentrations in plasma measured by a validated enzyme-linked immunosorbent assay (ELISA) were also compared. Two-year-old black porgy (n=20) were fed with estradiol-17β (4 mg kg(-1) of feed). Plasma was collected for purification of vitellogenin. Two forms of vitellogenin were found in plasma after chromatography on Sepharose CL-2B column and hydroxylapatite, and polyacrylamide gel electrophoresis. Black porgy vitellogenins are phospho-lipo-glycoproteins based on their chemical staining properties. The apparent molecular weights of the two forms of vitellogenin were 636 kDa and 321 kDa, respectively. The amino acid composition of purified vitellogenin was also analyzed after acid hydrolysis. The presence of immunoreactive vitellogenin was identified in the plasma and mucus extract from control and estradiol-induced females on the basis of Western blotting. Serial dilution of the plasma and mucus extract taken from estradiol-induced black porgy showed reactivity to an antiserum against lipovitellin in the ELISA, whereas mucus extract and plasma from male fish did not. Significantly higher concentrations of plasma vitellogenin were detected in estradiol-stimulated black porgy than in the control males.

The impact of endoscopic variceal ligation on the pressure of the portal venous system

BACKGROUND/AIMS

Endoscopic variceal ligation is a viable substitute for injection sclerotherapy. It is still not known how endoscopic variceal ligation may influence the portal venous system. To clarify this issue we investigated the impact of endoscopic variceal ligation on the pressure of the portal venous system.

METHODS

Twenty-nine patients with a history of esophageal variceal bleeding but without ascites were enrolled. All had cirrhosis; 63% of them were post-hepatitic. Ligation was performed at intervals of 2-3 weeks until all the varices were obliterated. Portal venograms were performed before institution of ligation and after variceal obliteration to assess venographic findings and pressure changes. The pressures of the main portal vein, splenic vein and superior mesenteric vein were recorded.

RESULTS

Twenty-five patients completed the study. A mean of 4.4 sessions (range: 2-7) of ligation over a period of 2 months was needed. Seventeen (68%) patients experienced elevated pressure and eight (32%) patients reduced pressure after ligation. Mean (median) pressure changes were as follows: portal venous pressure, 26.5 +/- 4.7 (25.0) mmHg vs. 28.2 +/- 7.2 (28.0) mmHg (p > 0.05); splenic venous pressure, 28.2 +/- 4.9 (26.0) mmHg vs. 29.0 +/- 6.8 (29.0) mmHg (p > 0.05); superior mesenteric venous pressure, 28.4 +/- 6.0 (27.0) mmHg vs. 29.5 +/- 7.0 (29.0) mmHg (p > 0.05). Five patients (20%) experienced rebleeding before variceal obliteration; all of them presented elevated portal pressures after variceal obliteration. Among the eight patients with decreased portal pressure, seven (87%) had other major collaterals apart from esophageal varices, compared to three out of the 17 (18%) patients with elevated portal pressure who had other major collaterals (p < 0.01).

CONCLUSIONS

Among patients receiving endoscopic variceal ligation, 68% experienced elevated portal pressure, while 32% had decreased portal pressure. Elevation of portal pressure after variceal ligation may be an important factor in variceal rebleeding. The presence of other major collaterals apart from esophageal varices may be responsible for the decrease in portal pressure after obliteration of esophagel varices.

Roles of a membrane-localized beta subunit in the formation and targeting of functional L-type Ca2+ channels

We report several unexpected findings that provide novel insights into the properties and interactions of the alpha 1 and beta subunits of dihydropyridine-sensitive L-type channels. First, the beta 2a subunit was expressed as multiple species of 68-72 kDa; the 70-72-kDa species arose from post-translational modification. Second, cell fractionation and immunocytochemical studies indicated that the hydrophilic beta 2a subunit, when expressed alone, was membrane-localized. Third, the beta 2a subunit increased the membrane localization of the alpha 1 subunit and the number of cells expressing L-type Ca2+ currents, without affecting the total amount of the expressed alpha 1C subunit. Expression of maximal currents in alpha 1C/beta 2a cotransfected cells paralleled the time course of expression of the beta subunit. Taken together, these results suggest that the beta subunit plays multiple roles in the formation, stabilization, targeting, and modulation of L-type channels.

Estradiol-17β suppresses testicular development and stimulates sex reversal in protandrous black porgy, Acanthopagrus schlegeli

Two year old black porgy (Acanthopagrus schlegeli) fed a diet containing 4.0 mg kg(-1) of estradiol-17β (E2) for 5 months had significantly lower GSI than the control group during the spawning season. E2 suppressed testicular development, spermiation and plasma testosterone (T) and 11-ketotestosterone (11-KT) and stimulated ovarian development, vitellogenesis and sex reversal. Spermiation in the control group occurred in January and February with the concentrations of 1.08-1.36 × 10(10) sperm ml(-1) of milt. Higher plasma T and 11-KT, but lower E2 levels were detected in the spermiating fish (control group). Higher plasma E2 levels were detected in the sex reversing black porgy during the pre-spawning season. A sharp rise in plasma 11-KT and a drop in T levels were detected in spermiating fish (control group) from January to February. Plasma 11-KT levels correlated with the testicular development and spermiation. The data suggest that E2 plays an important role in controlling the sex reversal of black porgy.

Stimulation of spermatogenesis or of sex reversal according to the dose of exogenous estradiol-17 beta in juvenile males of protandrous black porgy, Acanthopagrus schlegeli

The objective was to investigate the effects of various doses of estradiol-17 beta (E2) on gonadal development, gametogenesis, and plasma levels of sex steroids in 1-year-old protandrous male black porgy, Acanthopagrus schlegeli. Juvenile black porgy were divided into four groups, fed with control diet or diet mixed with E2 (0.25, 1.0, or 4.0 mg/kg feed) for 7 months, respectively. Significantly higher gonadosomatic index was observed in the 0.25- and 1.0-mg E2 groups compared to that in the control and 4.0-mg E2 groups during the spawning season. E2 at 4.0 mg completely suppressed spermiation, while lower doses of E2 (0.25 and 1.0 mg) delayed spermatogenesis but increased the number of spermiating fish and spermiation volume. Sperm concentrations were similar in spermiating black porgy. At 10 months and older, gonads in all the groups except E2 (4.0-mg)-treated fish underwent an intensive spermatogenesis while spermatids were not observed until 11 and 12 months in the 0.25- and 1.0-mg E2 groups, respectively. Primary oocytes appeared in the 10- and 11-month-old gonads in testicular tissue of the 1.0- and 4.0-mg E2 groups. After 5 months of 4-mg E2 treatment, testicular tissue regressed and ovarian tissue with primary oocytes developed. Elevated levels of plasma E2 were observed only in the 4.0-mg E2 group while low levels of E2 and testosterone (T) were observed in the control and other E2-treated groups. Significantly higher levels of plasma 11-ketotestosterone (11-KT) were observed in the 0.25- and 1.0-mg E2-treated groups during the spawning season. Plasma vitellogenin levels showed a dose-dependent effect of E2 treatment. The present data suggest that exogenous E2 could stimulate the development of either testicular or ovarian tissues, depending on the dosage of E2. Plasma 11-KT but not T concentrations closely correlate with testicular development and spermiation in black porgy.

TennCare--health system reform for Tennessee

TennCare, the health care system reform plan implemented in Tennessee on January 1, 1994, was developed with the dual objectives of controlling the rapidly rising cost of the state's Medicaid program and extending health insurance coverage to most Tennesseans without access to employer-sponsored or other government-sponsored health insurance. Beneficiaries enroll in competing, state-chartered managed care organizations that are responsible for providing broad preventive, inpatient, and outpatient services and are reimbursed by the state on a capitation basis at a rate based on a statewide global budget for health care. The program initially proposed to enroll up to 1,775,000 citizens and was projected to result in a cumulative cost savings to Tennessee and the federal government of $7.2 billion by the end of the 5-year demonstration period. However, major start-up problems encountered by the state and by managed care organizations and limitations imposed by the government have significantly constrained these expectations. At the end of its first year, more than 1.2 million citizens were enrolled, but the program incurred a $99 million deficit. Managed care organizations and hospitals have reported major financial problems, and constituency groups--especially those representing physicians--have attempted to block the program. Our objective is to describe the design and rationale of TennCare and discuss key issues the plan continues to face that may affect its long-term success.

Isolation and characterization of a type II JC virus from a brain biopsy of a patient with PML

Brain tissue of a patient with multiple myeloma suffering from neurological disorders similar to those seen in progressive multifocal leukoencephalopathy (PML) patients was evaluated for the presence of the papovavirus, JCV. Results from polymerase chain reaction (PCR) revealed the presence of JCV with structural organization at the control region which is distinct from well-characterized isolates, ie Mad-1 and Mad-4. The control region of the new isolate, named JCVPhila-1' contains a 22 nucleotide insertion which separates the TATA box from the NF-1 regulatory motif. Only 18 nucleotides of the insert are duplicated in the second copy of the enhancer/promoter of the new isolate, which is 84 nucleotides in size. Results from a transcription assay indicate a modest elevated level of JCVPhila-1 early promoter activity compared to that of JCVMad-4 in glial cell lines. The basal and T-antigen-induced transcriptional activities of the JCVPhila-1 late promoter was lower with respect to Mad-4 late gene activity in glial cells. Of particular interest was the observation that in the cells producing the early protein, T-antigen, JCVPhila-1 DNA replicated more efficiently then the Mad-4 DNA. These results suggest that the alterations seen in the JCVPhila-1 control region may differentially influence early and late gene expression and facilitate amplification of the viral genome in cells derived from the CNS.

The evolving changes in healthcare reform. Keynote speech given at the 1994 National Academy of the Intravenous Nurses Society in Atlanta, Georgia

This article explores three major health reform questions: (1) Why do we need to reform a system that provides cutting-edge healthcare? (2) What are the consequences of inaction? (3) Why is it so difficult to carry out a reform that has the support of most Americans? Based on the answers to these three questions, the article offers a two-prong reform alternative. First, seek a national consensus on why we disagree on healthcare. Second, let the states experiment with several promising and competing reform plans before committing to a national level reform.

A prospective, randomized trial of sclerotherapy versus ligation in the management of bleeding esophageal varices

We conducted a prospective, randomized trial comparing sclerotherapy and ligation in 120 patients with acute bleeding of esophageal varices. All the patients were cirrhotic, 59 received sclerotherapy, and 61 received ligation. Treatment was repeated regularly until the varices were obliterated. The mean follow-up period was 295 +/- 120 days and 310 +/- 105 days for the sclerotherapy and ligation groups, respectively. The control of active bleeding was 12/15 (80%) in the sclerotherapy group and 18/19 (94%) in the ligation group (P = .23). The numbers of treatment sessions required to achieve variceal obliteration were 6.5 +/- 1.2 in the sclerotherapy group and 3.8 +/- 0.4 in the ligation group (P < .001). Recurrent bleeding from the gastrointestinal tract was 51% in the sclerotherapy group compared with 33% in the ligation group (P < .05). Recurrent bleeding from esophageal varices was 36% in the sclerotherapy group and 11% in the ligation group (P < .01). However, bleeding from ectopic varices and congestive gastropathy was less common in the sclerotherapy group (7%) than in the ligation group (18%) (P = .05). Significant complications were encountered in 19% of the sclerotherapy group and in 3.3% of the ligation group (P < .01). Comparison of Kaplan-Meier estimates of time to death of both groups showed a significantly lower mortality in the ligation group (P = .011). Both sclerotherapy and ligation can effectively arrest active bleeding from esophageal varices. However, ligation is more effective than sclerotherapy in decreasing the risk of rebleeding from esophageal varices with fewer complications. Ligation can also achieve obliteration of esophageal varices more rapidly than sclerotherapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Factors influencing the success rates of endoscopic nasobiliary drainage in treatment of obstructive jaundice

BACKGROUND

Endoscopic nasobiliary drainage (ENBD) is a safe and effective modality which has been well documented for obstructive jaundice. However, factors predicting success rate of ENBD remain inconclusively. This study analyses those factors and discusses the outcome of patients with obstructive jaundice.

METHODS

One hundred and sixteen patients (male 99, female 17; mean age 68.2 years) with obstructive jaundice received ENBD after endoscopic retrograde cholangiogram (ERC) by Olympus JF-lT20 endoscope and 7F Wilson-Cook nasobiliary catheter from Sep. 1990 to Oct. 1993. Bile output (QD), serum bilirubin (BIW), liver biochemistry (QW), bile culture (next day), blood culture (if BT > 38.5 degrees C) were checked until definite treatment or death. Adequate drainage was defined as a daily output of bile more than 200cc, a gradual drop in serum bilirubin and no signs of cholangitis. Factors such as causes of jaundice, obstruction level, serum bilirubin, albumin, juxtapapillary diverticulum (JPD), bacteremia, fever before ERCP and ascites were analyzed.

RESULTS

The success rate was 86.2% (100/116) in ERC and 78% (78/100) in ENBD. Adequate biliary drainage was 82.1% (64/78), and serum bilirubin was reduced from 14.3 +/- 8.5 mg% to 7.5 +/- 5.6 mg% within one week. In patients with non-cancerous causes, higher success rate and adequate drainage rate were obtained compared with those with cancerous causes (94.3% vs. 69.2%, p < 0.01 and 88.6% vs. 50.8%, p < 0.01, respectively). In all patients, a higher success rate was achieved at the obstruction level at the common bile duct (CBD) compared with periampullary and hilar levels (90.7% vs 69.2%, p < 0.05 and 90.7% vs 28.6%, p < 0.001, respectively). In patients with cancer as a cause, higher success rate was achieved at CBD level than at hilar level (85% vs 28.6%, p < 0.05). Those patients with cancer and serum bilirubin above 15 mg/dl had a higher failure rate in ENBD. Success rate of ENBD was not related to the presence of JPD, bacteremia or fever before ERCP and serum albumin level.

CONCLUSIONS

Factors decreasing the success rates of ENBD were underlying cancerous causes, obstruction level at hilum or periampullary region and serum bilirubin level more than 15 mg%.

Clinical significance of intratumoral blood flow in cervical carcinoma assessed by color Doppler ultrasound

BACKGROUND

Much evidence has suggested that vascular density reflects the clinical behavior of cancer. In this study, the intratumoral blood flow in cervical carcinomas was assessed by transvaginal color Doppler ultrasound, and its clinical significance was evaluated.

METHODS

Sixty-five patients with Stage Ib-IIb cervical carcinoma exhibiting visible cervical tumor by transvaginal ultrasound were enrolled. All patients were scheduled for radical hysterectomy and pelvic lymph node dissection. Transvaginal color Doppler ultrasound was performed before surgery to search for blood flow signals from the tumor and the main uterine artery. The corresponding arterial resistance index (RI) was calculated. Clinical and pathologic data were recorded. A cytokinetic study was performed by propidium iodide staining and flow cytometry. The human papillomavirus (HPV) status was assessed by polymerase chain reaction.

RESULTS

Intratumoral blood flow was detected by color Doppler ultrasound in 46.2% (30/65) of the tumors. Patients with detectable intratumoral blood flow exhibited significantly more pelvic lymph node metastasis (10/30 vs. 2/35, P = 0.005), a higher percentage of cancer cells in the S- + G2M-phase (30.02 +/- 18.54% vs. 19.35 +/- 11.21%, P < 0.005), and a higher prevalence of HPV infection (30/30 vs. 25/35, P = 0.001) when compared with those without intratumoral blood flow. No significant difference was observed concerning the patient's age, tumor size, clinical staging, histologic type, and DNA ploidy status between these two groups. Regression analysis of the intratumoral RI value on the S- + G2M-phase fraction showed linear regression (n = 30, r2 = 0.501, P < 0.01). The RI values of the main uterine artery showed no significant difference between these two groups.

CONCLUSION

The intratumoral blood flow by transvaginal color Doppler ultrasound correlated well with a higher proliferation index, higher incidence of HPV infection, and pelvic lymph node metastasis in cervical carcinoma.

Cooperative action of cellular proteins YB-1 and Pur alpha with the tumor antigen of the human JC polyomavirus determines their interaction with the viral lytic control element

Human JC polyomavirus (JCV) is the etiologic agent of the neurodegenerative disease progressive mulifocal leukoencephalopathy. By using JCV as a model, we investigated the role of the viral early protein tumor antigen (TAg) in the binding of two cellular proteins, Pura alpha and YB-1, to JCV regulatory sequences. Results from band-shift assays with purified YB-1, Pur alpha, and TAg indicated that efficient binding of Pur alpha, a strong activator of early gene transcription, to a single-stranded target sequence corresponding to the viral lytic control element, is diminished in the presence of the late gene activator YB-1, which recognizes the opposite strand of the Pur alpha binding site. Of particular interest was the ability of Pur alpha and TAg to enhance binding of YB-1 to DNA molecules without being associated with this complex. Binding studies using a mutant peptide encompassing the N terminus of YB-1 indicated that the C terminus of YB-1 is important for its DNA binding activity. The ability of Pur alpha and TAg to increase binding of YB-1 to DNA is independent of the YB-1 C terminus. Similarly, results from band-shift assays using Pur alpha variants indicated that two distinct regions of this protein contribute either to its ability to bind DNA or to its ability to enhance YB-1 DNA binding activity. Based on the interaction of Pur alpha, YB-1, and TAg, and their binding to DNA, a model is proposed for the role of these proteins in transcription of viral early and late genes during the lytic cycle.

Immersion in bovine insulin stimulates growth of tilapia

The objective of this study was to investigate the effects of bovine insulin on growth responses in tilapia. Juvenile hybrid male tilapia (Oreochromis niloticus x O aurea; n = 135) were subjected to 1 of 3 treatments. Each treatment was subdivided into 3 replicates of 15 fish each. The fish were immersed into 1 of 2 doses (10 and 100 micrograms/100 ml water) of insulin or no hormone for 15 min per week for 8 weeks. Body weight, growth and feed conversion efficiency were significantly higher as a result of the first 4 weeks of insulin treatment as compared to control fish. The lower dose of insulin had a better stimulation effect than that of the higher doses. Insulin also stimulated feed consumption. Liver protein and protein/DNA ratio were higher in both insulin-treated groups than in the control group. Muscle proximate composition and hepatosomatic index were similar in the insulin-treated and control groups. The experimental findings suggest that insulin administered by immersion can enhance growth, feed consumption, food utilization and liver cell size in tilapia.