Identification of extracellular phospholipase B, lysophospholipase, and acyltransferase produced by Cryptococcus neoformans

We recently identified phospholipase activity as a potential virulence factor of Cryptococcus neoformans. We have now defined the nature of the phospholipase activity produced by a clinical isolate of C. neoformans var. neoformans, under native conditions, by 1H and 31P nuclear magnetic resonance (NMR) spectroscopy and thin-layer chromatography (TLC) of radiolabelled substrates. Glycerophosphocholine was identified by NMR spectroscopy as the sole phospholipid degradation product of the reaction between substrate phosphatidylcholine (PC) and cryptococcal culture supernatants indicating the presence of phospholipase B (PLB). No lysophosphatidylcholine (lyso-PC) or products indicative of phospholipase C, phospholipase D, or other lipase activity were identified. Use of PC and lyso-PC containing radiolabelled acyl chains and separation of products by TLC confirmed the PLB and lysophospholipase (LPL) activities. Lysophospholipase transacylase (LPTA) activity was identified by the formation of radioactive PC from lyso-PC. Extracellular enzyme production was maximal after 6 to 10 h in fresh medium. Assay conditions were optimized for pH, linearity with time, enzyme concentration, and saturation by substrates to allow comparison with phospholipases from other organisms. LPL activity was 10- to 20-fold greater than PLB activity, with mean (+/- standard deviation) specific activities of 34.9 +/- 7.9 and 3.18 +/- 0.2 micromol of substrate hydrolyzed per min per mg of protein, respectively. The response of PLB to increasing substrate concentrations was bimodal, whereas inhibition of LPL and LPTA activities occurred at concentrations of substrate lyso-PC greater than 200 microM. Enzyme activities were stable at acid pH (3.8), with pH optima of 3.5 to 4.5. Activities were unchanged in the presence of exogenous serine protease inhibitors, divalent cations, and EDTA. We conclude that C. neoformans produces highly active extracellular PLB, LPL, and LPTA under native conditions.

Phospholipase activity in Cryptococcus neoformans: a new virulence factor?

Fifty isolates of Cryptococcus neoformans were examined for extracellular phospholipase production after inoculation onto egg yolk agar; 49 produced a pericolonial precipitate indicative of phospholipase activity. Phospholipase B (PLB), lysophospholipase, and lysophospholipase-transacylase activities were identified by radiometric analysis in supernatants from 4 clinical isolates. The ratio of colony diameter to colony plus precipitate on agar (Pz) correlated with PLB activity. Phospholipase production was similar in 12 environmental and 13 clinical isolates of C. neoformans var. gattii. Environmental strains of C. neoformans var. neoformans (n = 8) produced more phospholipase at 72 h than did 17 clinical isolates (mean Pz, 0.57 vs. 0.72; P < .01); however, Pz values were similar at 96 h. Quantitation of cryptococci in the lungs and brains of BALB/c mice inoculated intravenously with 4 strains expressing high, intermediate, or low phospholipase activity revealed a correlation between phospholipase activity and virulence. Phospholipases secreted by C. neoformans may be implicated in virulence.

Mechanism underlying the effect of pregnenolone sulfate on the kainate-induced current in cultured chick spinal cord neurons

The effect of the neurosteroid pregnenolone sulfate on the kainate receptor-mediated response was studied in cultured chick spinal cord neurons using the whole-cell voltage-clamp recording technique. Pregnenolone sulfate rapidly and reversibly inhibits the kainate-induced current in a dose-dependent manner, with an EC50 of 67 microM and maximal inhibition of 38%. Inhibition by pregnenolone sulfate of the kainate response is not attenuated by increasing concentrations of kainate, suggesting that the blocking action of pregnenolone sulfate is non-competitive. Antagonism of the kainate response by pregnenolone sulfate is neither agonist- nor voltage-dependent, indicating that pregnenolone sulfate does not act as an open-channel blocker. Furthermore, our results demonstrate that pregnenolone sulfate and 1-(4-aminophenyl)-4-methyl-7,8-methylenedioxy-5H-2,3-benzodiazepine (GYKI 52466; a potent non-competitive kainate antagonist) do not act through a common site.

Counseling clinic for pediatric weight reduction: program formulation and follow-up

The feasibility and efficacy of an outpatient-based multicomponent weight reduction program was tested with 68 consecutively enrolled obese children and adolescents. The patients were invited to participate in an individualized six-session program that included parent involvement, diet education, exercise management and behavior modification by a culturally sensitive method. Fifty-six patients were followed up 1 year after treatment. Comparison at pretreatment, end-of-treatment and 1-year-after-treatment with respect to changes in degree of obesity, measured by weight-for-length index (WLI), showed statistically significant differences. Ninety-seven percent of participants were below their pretreatment WLI at the end-of-treatment examination, and 80% at 1-year-after-treatment follow-up. At 1-year-after-treatment, 59% showed a reduction in WLI of 0.1 or more, as compared with 38% of participants at end-of-treatment. Two parameters previously considered predictors of successful weight control, notably age of participants and percentage of weight lost during treatment, were significantly associated with a reduction in the degree of obesity after one year. Although the long-term efficacy cannot be determined, our results indicated that this comprehensive weight reduction program may have an encouraging effect on the weight status of obese Chinese children and adolescents.

Hemopneumothorax missed by auscultation in penetrating chest injury

OBJECTIVE

To determine the frequency and extent of hemothorax, pneumothorax, and hemopneumothorax missed by auscultation in penetrating chest injury.

DESIGN

A retrospective chart and chest radiograph review.

MATERIALS AND METHODS

One hundred and eighteen patients suffering penetrating chest injuries during 1993 were studied. A missed auscultation was defined as a patient with normal breath sounds but shown by chest radiograph to have a hemothorax, pneumothorax, or hemopneumothorax. The amount of hemothorax was recorded after chest tube placement or at thoracotomy. The degree of pneumothorax was determined by Rhea's method.

RESULTS

Seventy-one patients (60%) had a hemothorax, pneumothorax, or hemopneumothorax. Auscultation to detect hemothorax, pneumothorax, or hemopneumothorax had a sensitivity of 58%, a specificity of 98%, and a positive predictive value of 98%. Thirty of 71 patients (42%) were found to have pleural space blood or air missed by auscultation. Twelve patients (41%) had a hemopneumothorax, 11 patients (36%) had hemothorax, and seven patients (23%) had pneumothorax. Auscultation missed hemothorax up to 600 mL, pneumothorax up to 28%, and hemopneumothorax up to 800 mL and 28%.

CONCLUSION

Hemopneumothorax and hemothorax are the conditions most likely to be missed by auscultation, especially in patients with gunshot wounds. Auscultation has a high positive predictive value because it indicates injury with a fair degree of certainty; however, a negative auscultation does not rule out injury.

Inhibition of corticosterone secretion by thyroxine in male rats

The effects of thyroxine (T4) on the secretion of corticosterone both in vivo and in vitro in male rats were studied. Rats were thyroidectomized (Tx) or sham Tx. The Tx rats were subcutaneously with T4 (20 micrograms/kg) or saline once daily for two weeks. In an in vitro experiment, adrenal glands were incubated with ACTH, T4, or ACTH plus T4 in the presence or absence of 0.5 mM 3-isobutyl-1-methylxanthine (IBMX) at 37 degrees C for 60 min. Medium and ether-extracted plasma samples were analyzed for corticosterone by radioimmunoassay (RIA). The accumulation of cyclic adenosine monophosphate (cAMP) in adrenal tissues after incubation with IBMX was measured by RIA. The levels of plasma corticosterone in Tx rats were significantly increased as compared with euthyroid rats. T4 replacement in Tx rats restored plasma corticosterone to euthyroid level. Administration of T4 in vitro resulted in an inhibition of both basal and ACTH-stimulated release of corticosterone. Both basal and ACTH-stimulated generations of cAMP in adrenal tissues were decreased by T4. These results suggest that T4 inhibits the spontaneous and ACTH-stimulated secretion of corticosterone by acting directly at adrenal glands via a decrease in cAMP production.

Clinical utility of color Doppler sonography in the differentiation of hepatocellular carcinoma from metastases and hemangioma

The clinical utility of color Doppler sonography in the differentiation of hepatocellular carcinoma from metastases and hemangioma was investigated in 72 hepatocellular carcinomas (80 lesions), 30 metastases (82 lesions), and 39 hemangiomas (54 lesions). Overlaps of color patterns were found among hepatocellular carcinoma, metastases and hemangioma. Pulsatile waves from lesions with the basket, vessels within tumor, or spot patterns, or lesions measuring less than 3 cm with detectable signals, did not favor the diagnosis of hemangioma. In conclusion, color Doppler sonography can aid in the differentiation of hepatocellular carcinoma from hemangioma but may be unreliable in the differentiation of hepatocellular carcinoma from hypervascular metastases.

Identification and purification of a spinach chloroplast DNA-binding protein that interacts specifically with the plastid psaA-psaB-rps14 promoter region

We have previously shown the presence in chloroplasts of sequence-specific DNA-binding proteins that interact specifically with two regions located downstream and upstream from the 5'-transcription start site of the plastid psaA-psaB-rps14 operon. As part of an effort to elucidate the regulatory mechanism of plastid transcription during plant development, we report here the purification and characterization of the chloroplast DNA-binding protein from spinach (Spinacia oleracea L. var. spinosa Ashers et Graeden) leaves that specifically recognizes sequences between positions +64 to +83 relative to the transcription start site. This DNA-binding protein has been highly purified from chloroplasts by using a combination of high-salt extraction, ammonium sulfate precipitation, heparin-agarose chromatography, and sequence-specific DNA-affinity chromatography. The protein exhibited an apparent molecular weight of 59-60 kDa on the basis of gel filtration. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by Southwestern blot analysis further indicated that this DNA-binding protein is dimeric and composed of two approximately 31-kDa subunits. We discuss the properties of this protein in relation to the known chloroplast DNA-binding factors for plastid gene expression.

Protein characterization of fluorosed human enamel

Despite extensive investigation, the development mechanism or mechanisms resulting in dental fluorosis are unknown. Several hypotheses suggest abnormal matrix synthesis, secretion, and delayed and/or defective matrix degradation with retention of enamel protein. The purpose of this study was to characterize the protein composition of fluorosed human enamel. Nine permanent moderately fluorosed (developed in a 3.2 ppm H2O area) and ten permanent normal control teeth (from individuals with < 0.2 ppm F in their drinking water) were evaluated. The enamel fluoride concentration, protein content, and amino acid composition were determined for each tooth. The enamel proteins were further characterized by gel electrophoresis and by Western blot analysis by means of polyclonal antibodies raised against recombinant amelogenin protein. Fluorotic enamel had significantly elevated (p = 0.0001) F levels compared with normal enamel (mean [F-] fluorosed = 431 ppm; mean [F-] control = 62 ppm). While there was a significantly greater protein content by weight in fluorosed enamel compared with normal enamel (mean fluorosed = 0.27%; mean control = 0.11%), the amino acid profiles were similar for fluorosed and normal enamel. Gel electrophoresis showed fluorosed enamel to have a greater diversity of primarily low-molecular-weight proteins compared with normal enamel. Western blot analysis did not indicate retention of amelogenin in either fluorosed or normal enamel. This investigation showed that the protein content of fluorosed enamel was greater than that of normal enamel; however, the amino acid compositions were similar for fluorosed and normal enamel. Furthermore, there does not appear to be retention of significant amounts of amelogenin in fully mature, moderately fluorosed human enamel. Although delayed removal of the enamel matrix proteins may play a role in the hypomineralization defects seen in fluorosed enamel, the majority of these proteins are absent in the mature tissue of these moderately fluorosed teeth.

The genotypes of hepatitis C virus in patients with chronic hepatitis C virus infection in southern Taiwan

To investigate the genotype distribution of hepatitis C virus (HCV) in southern Taiwan, the sera from 56 patients with chronic HCV infection were studied. Twenty-nine patients were men and 27 were women. Age ranged from 22 to 65 years (mean, 47.3 +/- 11.4). Eighteen of them had chronic persistent hepatitis, 27 had chronic active hepatitis, and 11 had liver cirrhosis. HCV RNA was detected by reverse transcription-nested polymerase chain reaction using primers derived from the 5'-noncoding region. The genotypes of HCV were determined by amplification of the core region with the type-specific primers as described by Okamoto et al.. All sera were positive for HCV RNA. The prevalence rates of genotypes were as follows: 1b/II, 44.6%(25/56); 2a/III, 41.1%(23/56); 2b/IV, 3.6%(2/56); mixed 1b/I + 2a/III, 5.4%(3/56): mixed 1b/II + 2b/IV, 1.8%(1/56) and type unclassified 3.6%(2/56). The distribution of genotypes was not related to the patients' age, sex, and histological changes. Nevertheless, patients having past history of blood transfusion had a significantly higher rate of HCV type 2a/III infection (72.2% versus 34.2%, p < .05, chi-square test). We concluded that both of the HCV genotypes 1 b/II and 2a/III are predominant types in southern Taiwan and regional HCV genotype distribution may differ even within this island. Selective transmission of specific genotypes may pass along different infectious routes.

Techniques for intrasplenic hepatocyte transplantation in the large animal model

BACKGROUND

The preferred therapy for acute and chronic liver insufficiency and severe heritable disorders of liver metabolism is whole-organ transplantation. However, due to the shortage of organ donors and high cost, alternative therapeutic approaches have been proposed, including transplantation of normal allogeneic hepatocytes. Recently, it has been reported that many hepatocytes transplanted into the spleen migrated to the liver. We therefore carried out a series of large-animal experiments to reexamine the intrasplenic route and to develop a method for large-scale hepatocellular transplantation in pigs.

METHODS

Allogeneic porcine hepatocytes were transplanted using the following routes: (1) retrograde injection of cells via the splenic vein, (2) intraarterial injection of cells, (3) direct intrasplenic injection of cells after laparotomy, (4) percutaneous intrasplenic injection of cells under laparoscopic control, (5) laparoscopic intrasplenic injection of cells. The number of cells injected varied from 2 x 10(9) to 10 x 10(9) cells.

RESULTS

Of all the methods tested, only direct intrasplenic injection of 2 bln of cells was found to be compatible with survival. However, even with this "small" number of cells (2% original liver mass), there was a significant risk of spleen infarction, perisplenic adhesion formation, and portal vein thrombosis. The laparoscopic approach was found to be reliable, simple, and safe.

CONCLUSION

Even though the spleen is considered by many authors the optimal site for hepatocellular transplantation, transplantation of cells in a number needed to support the failing liver may be associated with significant complications, morbidity, and mortality.

Platelet-derived growth factor is an autocrine stimulator for the growth and survival of human esophageal carcinoma cell lines

Platelet-derived growth factors (PDGF) are important mitogens for mesenchyme-derived cells. Neither PDGF nor PDGF receptors (PDGFR) are expressed in epithelial cells under normal physiological conditions. However, we have found that PDGF-BB induces c-jun expression and promotes the growth of the human esophageal carcinoma cell line CE48T/VGH. Scatchard analysis revealed the presence of 6 x 10(5) binding sites for PDGF-BB per cell, with a Kd of 9.7 nM. Furthermore, our data indicate that CE48T/VGH expresses beta type PDGFR (PDGFRbeta) with in vitro auto-kinase activity. We have also found that CE48T/VGH expresses the mRNA of the PDGF-A and PDGF-B chains and secretes PDGF molecules. Addition of anti-PDGF neutralizing antibody significantly decreased cell numbers of CE48T/VGH under serum-free conditions. The detached cells underwent apoptosis characterized by micronucleation. These results suggest that expression of the PDGF autocrine system may not only provide the growth advantage but also prevent the apoptosis for CE48T/VGH.

The practice of Chinese medicine in Taiwan

This paper examines the practice of Chinese medicine in Taiwan. Using a national sample survey of Chinese medicine physicians, supplemented by another national survey of Chinese medicine hospitals and government records, the authors study the education and training background of Chinese medicine physicians, their mode of practice, their productivity measured by patient visits, and the practice characteristics of Chinese medicine hospitals. Moreover, the authors investigate the relationship between the resource input, the public health insurance contract, and the number of patient visits Chinese medicine physicians provided. Results of this study are used to make several recommendations on the appropriate way of integrating the practice of Chinese medicine into the modern health care system. Many of these recommendations may also be applicable to other countries that are contemplating integrating traditional or alternative medicine into their health care systems.

Characterization of Cryptococcus neoformans by random DNA amplification

Random amplified polymorphic DNA (RAPD) was optimized and used to distinguish between the varieties and serotypes of Cryptococcus neoformans. The RAPD technique distinguished between serotypes A, D or AD within C. neoformans var. neoformans, and revealed further differentiation within each serotype. Four RAPD profiles were clearly recognizable within C. neoformans var. gattii, although its two serotypes, B and C, were only differentiated with one primer combination out of seven.

Surgical treatment of choledochal cyst in adults: results and long-term follow-up

BACKGROUND/AIMS

Results of the surgical management of 60 adults with choledochal cysts at Chang Gung Memorial Hospital Taipei are presented.

PATIENTS AND METHODS

All patients were diagnosed and surgically managed during the period between March 1979 and December 1992. There were 47 females and 13 males, with ages ranging from 16 to 81 years (mean age = 31.9 years). Of the total, there were 41 Type I, one Type II, 14 Type IV, and four Type V choledochal cysts classified according to Todani's classification system. The definite surgical procedures were cyst excision and hepatico-jejunostomy in 43 cases in type I and IV diseases, one cyst excision in type II disease, two hepatectomy for type V disease, cyst enterostomy in seven cases, and T-tube choledochocystostomy in seven cases.

RESULTS

The operative mortality rate was 3.3% and the complication rate related to the surgical procedure was 20%. Early postoperative complications include wound infection, leakage of anastomosis, acute pancreatitis, septic shock, left pleural effusion, and intra-abdominal abscessing. Reoperations were needed in the early postoperative days in two cases due to hepatico-jejunostomy leakage and intraabdominal abscess formation. Long-term surgical outcome, concerning recurrence of symptoms, was related to the following factors, excluding the factors of surgery: presence of bile duct lithiasis, common channel less than 22 mm, presence of preoperative pancreatitis and acute angle type pancreaticobiliary unions. Only common channel less than 22 mm is statistically significant. The percentage of recurrence of the symptoms after resectional surgery was 32.5% in the long term follow-up period. Most of the cases responded well to an antibiotics treatment. Three of the cases required a second operation or PTCD as well as dilatation to treat the recurrent cholangitis.

CONCLUSION

Although the recurrence of symptoms is not uncommon and satisfactory explanation of the analysed factors is still the treatment of choice for adult patients with choledochal cysts.

Urethral recurrence in patients with orthotopic ileal neobladders

PURPOSE

We identified the risk of urethral recurrence following cystectomy for transitions cell bladder carcinoma, stratified by pathological characteristics of the bladder tumor and type of urinary diversion.

MATERIALS AND METHODS

The pathological characteristics and clinical courses of 174 men with a Kock ileal neobladder and 262 with a cutaneous urinary diversion were analyzed for time to urethral recurrence.

RESULTS

Urethral recurrence was identified in 34 patients at a median of 1.6 years after cystectomy, for an overall 7.9% 5-year risk of recurrence. Carcinoma in situ (p = 0.71) and multifocality (p = 0.17) did not independently confer an increased risk of recurrence. Prostatic urethral involvement, particularly stromal invasion, significantly increased the probability of recurrence (p < 0.001). Patients with a Kock ileal neobladder had a significantly lower probability of recurrence compared to those with cutaneous diversion (p = 0.015), even when associated with prostatic urethral involvement.

CONCLUSIONS

Patients with a Kock ileal neobladder have a lower risk of urethral recurrence than those with cutaneous urinary diversion, even when associated with a high risk pathological condition predicting increased risk of urethral recurrence.

Effect of chronic captopril treatment on circulating and tissue renin-angiotensin system in SHR rats

AIM

To study the effect of captopril treatment and its withdrawal on the circulating and tissue peptidyl-dipeptidase A, angiotensinogen (AGT), and angiotensin II (A II), in relation to left ventricular hypertrophy (LVH) and systolic blood pressure (SBP).

METHODS

SHR male rats were given captopril 100 mg.kg-1.d-1 [SHRcap, number (n) = 43] orally in mixture with milk powder as vehicle from intrautero period of 16 wk of age. Rats were killed at 16 (n = 19) and 40 (n = 24) wk of age, respectively. Male, age-matched untreated SHR and WKY rats served as controls. SBP, left ventricular mass/body weight (LVM/BW) ratio, left ventricular (LV) myocardium and plasma A II concentration, aortic and serum peptidyl-dipeptidase A activity, AGT mRNA level in kidney and liver, renal renin mRNA level were determined.

RESULTS

Captopril treatment decreased SBP and reduced LVM/BW at 16 and 40 wk of age, and persistently inhibited LV myocardium A II, aortic peptidyl-dipeptidase A activity, and AGT gene expression in kidney even after the treatment was removed. Nevertheless, no changes were found in plasma A II concentration, serum peptidyl-dipeptidase A activity, and AGT mRNA level in liver by captopril therapy. Renal renin mRNA level was low in SHR and WKY rats, but it was increased by captopril treatment. Tissue renin-angiotensin system (RAS) such as AGT mRNA in kidney, aortic peptidyl-dipeptidase A activity, and LV myocardium A II, rather than circulating RAS (AGT mRNA in liver, renin mRNA in kidney, serum peptidyl-dipeptidase A activity and plasma A II), were persistently inhibited by early captopril treatment, even after the withdrawal of the treatment.

CONCLUSION

The long-term inhibition of tissue RAS is one of the mechanisms of the persistent hypotensive effect of captopril treatment.

Clinical experience with a porcine hepatocyte-based liver support system

The only clinically proven effective treatment of fulminant hepatic failure (FHF) is orthotopic liver transplant (OLT). However, many patients die before an organ becomes available. Thus, there is a need for development of an extracorporeal liver support system to "bridge" these patients either to OLT or spontaneous recovery. We developed a bioartificial liver (BAL) based on plasma perfusion through a circuit of a hollow-fiber cartridge seeded with matrix-anchored porcine hepatocytes to treat patients with severe acute liver failure. Two groups of patients were studied. Group 1 (n = 12): patients with FHF. All patients were successfully "bridged" to OLT. "Bridge" time to OLT was 21-96 hr (mean: 39.3 hr). All patients were discharged neurologically intact. Reversal of decerebration was noted in all 11 deep stage 4 coma patients. There was reduction in intracranial pressure (ICP mmHg, 18.2 +/- 2.2 to 8.5 +/- 1.2; p < 0.004) and increase in cerebral perfusion pressure (CPP mmHg, 71.1 +/- 4.0 to 84.7 +/- 2.6; p < 0.006). Laboratory values pre- and post-BAL treatment: glucose (mg/dl) 122 +/- 11 to 183 +/- 21, p < 0.002; ammonia (mumol/l) 155.6 +/- 13.2 to 121.6 +/- 9.5, p < 0.02; total bilirubin (mg/dl) 21.6 +/- 2.8 to 18.2 +/- 2.2, p < 0.001; PT (sec) 23.2 +/- 1.7 to 21.9 +/- 1.0, p < 0.3. Group II (n = 8): patients with chronic liver failure experiencing acute exacerbation. Two patients survived and later underwent OLT. Six patients (not OLT candidates) died 1-14 days after last BAL treatment. Laboratory values pre- and post-treatment: ammonia (mumol/l) 201 +/- 47 to 143 +/- 25, p < 0.06; total bilirubin (mg/dl) 22.8 +/- 5.2 to 19.5 +/- 4.4, p < 0.01; PT (sec) 22.5 +/- 2.0 to 21.8 +/- 1.1, p < 0.6.

CONCLUSION

our clinical experience with the BAL suggests that it may serve as "bridge" to OLT in patients with FHF primarily by reversing intracranial hypertension, but it is not a substitute for OLT in patients with end-stage liver disease who are non-transplant candidates.

Introduction and expression of foreign DNA in isolated spinach chloroplasts by electroporation

An electroporation-mediated method for the study of foreign gene expression within chloroplasts has been developed. The chloroplast expression vector pHD203-GUS, which consists of coding regions for beta-glucuronidase (GUS) and chloramphenicol acetyltransferase (CAT) separated by a double psbA promoter fragment from pea (in opposite orientation) was electroporated into spinach chloroplasts and the transient gene expression was examined. Conditions for the expression of the reporter genes have been optimized. Both CAT and GUS activities were detected in chloroplasts electroporated with pHD203-GUS, but not with nuclear expression vector pBI221 or negative control pUC18. No GUS activity was detected when pHD203-GUS was electroporated into spinach protoplasts. Dot immunoblot analysis using anti-GUS antibody confirmed the existence of GUS protein in chloroplasts electroporated with chloroplast-specific vector but not the negative controls, excluding the possibilities of endogenous GUS or bacterial contamination. The expression of GUS protein in treated chloroplasts was further confirmed by Western blot analysis.

Treatment of chronic hepatitis C with interferon-alpha: a preliminary report

Interferon alpha (IFN-alpha) has been indicated to be dramatically effective in some but not all patients with chronic hepatitis C virus (HCV) infection. We investigated prospectively 27 patients of chronic hepatitis C, 12 females and 15 males, treated with IFN-alpha for a better regimen of the therapy and for any effective predictor of response to the treatment. All patients were treated with 3 to 6 million units (MU) of recombinant IFN-alpha 2b (n = 15) or lymphoblastoid IFN-alpha (n = 12) given 3 times weekly for 12 to 36 weeks. Patients with normal alanine aminotransferase (ALT) value during therapy, who sustained this response throughout 6 months follow-up after treatment was completed, were grouped into the complete responders. Patients with normal ALT value during therapy but who relapsed after treatment completed, were grouped as partial responders. Non-responders were defined as patients without normal ALT value during therapy. The rates of complete response, partial response, and non-response were 29.6%, 40.8%, and 29.6%, respectively. The degree of response to IFN-alpha therapy was not related to age, sex, type of IFN-alpha, history of blood transfusion, the state of liver pathology, or pretreatment level of ALT value. The complete responsive rate to IFN-alpha was higher in patients treated with total dose above 215 MU [38.1% (8/21) vs. 0% (0/6), p = 0.06], in patients treated for at least 24 weeks [40% (8/20) vs. 0% (0/7), p < 0.05], and in patients with non-genotype 1b/II HCV infection [40% (8/20) vs. 0% (0/7), p < 0.05]. We concluded that IFN-alpha was effective in the treatment of chronic HCV infection, particularly in those other than HCV genotype 1b/II. A high-dose, and long-duration regimen may be recommended for better response of chronic hepatitis C to IFN-alpha therapy.

Treatment of hypercholesterolemia in the Watanabe rabbit using allogeneic hepatocellular transplantation under a regeneration stimulus

Numerous studies have reported successful allotransplantation of hepatocytes. However, none have shown long-term correction of a liver-related metabolic defect. In this study, we used a method of regional hepatocyte transplantation and subsequent induction of transplanted cell proliferation by regeneration response in the transplant-bearing liver lobes. New Zealand White rabbits were used as cell donors and Watanabe heritable hyperlipidemic (WHHL) rabbits were used as cell recipients (2 x 10(8) cells/rabbit). All recipient rabbits were maintained on daily cyclosporine. Two weeks after baseline serum cholesterol determination, group I WHHL rabbits (n = 7) received an infusion of cells into the right lateral liver lobe, and a loose ligature was placed around the portal venous branch supplying the anterior lobe. After 1 week, to allow engraftment, the portal venous branch was ligated, which resulted in the atrophy of the affected liver parenchyma and induction of hyperplasia in the transplant-bearing liver tissue. Group II rabbits (n = 6) were transplanted with New Zealand White hepatocytes without portal branch ligation (PBL) and group III rabbits (n = 4) were subjected to sham transplantation (saline) and PBL. The experimental period extended to 150 days after transplantation. All WHHL rabbits transplanted with normal hepatocytes showed reduction in serum cholesterol and low-density lipoprotein (LDL) levels. Group I (PBL-stimulated) recipients demonstrated a more pronounced and sustained effect than group II animals (P < 0.05). Group III controls showed only a slight, typical for aging decrease in serum cholesterol. Group I recipient livers perfused with LDL labeled with 1,1'-dioctadecyl-3,3,3',3'-tetramethyl indocarbocyanine perchlorate (DiI) showed much higher numbers of DiI-LDL-positive hepatocytes than those of group II recipients. In conclusion, a liver regeneration stimulus enhanced the population of transplanted hepatocytes and their functional effect in a large animal model of inborn error of liver metabolism.

Transitional cell carcinoma involving the prostate with a proposed staging classification for stromal invasion

PURPOSE

We investigated the effect on survival of transitional cell carcinoma of the prostatic urethra, ducts and stroma, and determined the difference between prostatic stromal involvement occurring via direct extension through the bladder wall versus stromal invasion arising intraurethrally.

MATERIALS AND METHODS

Between August 1971 and December 1989, 489 men underwent radical cystoprostatectomy for transitional cell carcinoma, including 143 (29.2%) identified with prostate involvement by transitional cell carcinoma, in the cystectomy specimen. Patients were separated into 2 groups: 1-19 in whom the primary bladder tumor extended full thickness through the bladder wall to invade the prostate (classified as P4a) and 2-124 in whom prostate involvement arose from within the prostatic urethra.

RESULTS

Five-year recurrence-free and overall survival rates were 25 and 21%, respectively, in group 1 versus 64 and 55%, respectively, in group 2. In the 124 patients in group 2 survival rates were similar for those with prostatic urethral tumors or carcinoma in situ and ductal tumors (no stromal invasion). Five-year overall survival rates without and with stromal invasion were 71 and 36%, respectively (p < 0.0001). Transitional cell carcinoma of the prostatic urethra or ducts does not alter survival predicted by primary bladder stage alone. Prostatic stromal invasion arising intraurethrally significantly decreases survival, which varies based on primary bladder stage (64.6% in stage P1, 30.8% in stages P2/P3a and 13.6% in stage P3b, p = 0.0001). P1 bladder tumors with prostatic stromal invasion arising intraurethrally had a significantly higher survival rate than P4a tumors (64.6 versus 21%, p = 0.0001). P3b bladder tumors with stromal invasion had a survival rate similar to that of P4a tumors (p = 0.78).

CONCLUSIONS

Prostatic urethral or ductal transitional cell carcinoma does not alter survival determined by primary bladder stage alone and it should not be classified as P4a. Prostatic stromal involvement arising intraurethrally significantly decreases survival predicted by primary bladder stage alone. P1 bladder tumors with prostatic stromal invasion arising intraurethrally have a significantly higher survival rate than P4a tumors and they should be separately classified as P1str. Muscle invasive (P2/P3a) bladder tumors with stromal invasion have a higher survival rate than P4a tumors (no statistical significance) and they should be designated separately (that is P2str). P3b bladder tumors with prostatic stromal invasion arising intraurethrally are indistinguishable from P4a tumors.

Protection against rotavirus infections by DNA vaccination

DNA vaccines encoding for murine rotavirus proteins VP4, VP6, or VP7 were tested in adult BALB/c mice for their ability to induce immune responses and protect against rotavirus challenge. A gene gun was used to inoculate vaccines into the epidermis. Rotavirus-specific serum antibodies, as measured by ELISA, and virus-specific cytotoxic T lymphocyte responses were generated by each of the three vaccines, but virus-neutralizing antibodies were detected only in mice that were inoculated with DNA vaccines encoding for VP4 and VP7. Efficacy of the vaccines was determined by challenge with 100 ID50 of homotypic rotavirus. Each of the three vaccines was effective in protecting mice against infection after rotavirus challenge as determined by reduction (P < .001) in virus excretion in mice receiving the DNA vaccines. These results demonstrate that DNA vaccination has potential as a new approach for control of rotavirus infections.