Development and use of 16S rRNA gene targeted PCR primers for the identification of Escherichia coli cells in water

The primary sequences of the V3 and V6 regions of the 16S rRNA gene of pathogenic and non-pathogenic strains of Escherichia coli were determined and compared with those obtained for a number of reference strains which belong to the family Enterobacteriaceae. Three oligonucleotide primers 16E1, 16E2 and 16E3 were designed and used in the polymerase chain reaction to identify specifically all E. coli isolates. When 16E1, 16E2 and 16E3 were used as primers for the identification of E. coli cells present in tap, underground and pond waters, as low as 1 cfu 100 ml-1 of water could be detected if an 8 h pre-culture step was performed prior to the PCR reaction.

The additive effect of sclerotherapy to patients receiving repeated endoscopic variceal ligation: a prospective, randomized trial

Endoscopic variceal ligation (EVL) is a new technique designed to manage esophageal varices. The effect of sclerotherapy following repeated banding ligation remains unknown. Seventy-two patients with a history of esophageal variceal bleeding received regular EVL until variceal disappearance or until left with residual small varices. Subsequently, patients were randomized to receive sclerotherapy (Group 1, 37 patients) or serve as a control (Group 2, 35 patients). Group 1 received one to two sessions of low-dose sclerotherapy to achieve complete variceal disappearance. After a mean follow-up of 2 years, 4 months, recurrent esophageal varices developed in 14% of Group 1 and 43% of Group 2 (P < .02). Rebleeding was encountered in 8% of Group 1 versus 31% of Group 2 (P = .01). One case of esophageal stricture (2.7%) was encountered in Group 1. One patient in Group 1, compared with 3 patients in Group 2, died of massive variceal bleeding (P > .05). The multivariate Cox model indicated that treatment was the only factor predictive of variceal recurrence, and both Child-Pugh class and treatment were factors predictive of variceal rebleeding. The addition of low-dose sclerotherapy following repeated banding ligations proved safe and effective in the prevention of recurrence of esophageal varices and rebleeding.

Dissolution difference between acidic and neutral media of acetaminophen tablets containing a super disintegrant and a soluble excipient. II

The disintegration and dissolution of acetaminophen tablets containing sucrose and Ac-Di-Sol/Primojel was significantly different between acidic and neutral media. The purpose of this study was to investigate the mechanism of this phenomenon and to propose a way of reducing the dissolution difference between the two media. Tablets of different combinations of active ingredient, sucrose, and Ac-Di-Sol/Primojel were prepared and their dissolution in various media was evaluated. The dissolution differences were found to be largely related to the hydrophobicity of the active ingredient and pH difference of the two media. This difference was even more evident under the condition where acetaminophen, sucrose, and Primojel were combined. The dissolution difference was therefore attributed to the depressed function of Primojel in the acidic medium, the stronger binding of sucrose, the hydrophobicity of the active ingredient and pH difference of the two media. Increasing the concentration of Primojel or incorporating the surfactant in the tablet can thus greatly decrease the dissolution difference between acidic and neutral media.

The first case of the p phenotype in a Gurkha Nepalese

A serum sample from a Gurkha Nepalese soldier, residing in Hong Kong, was found to cause hemolysis of reagent ABO red cells (RBCs) in the reverse blood grouping test. Subsequent follow-up studies revealed that he was of the p phenotype, with potent anti-PP1Pk that was strongly hemolytic both at room temperature and 37 degrees C. The anti-PP1Pk was composed of IgG and IgM, and its various components were separable.

Correlation of serum immunoglobulin G Helicobacter pylori antibody titers with histologic and endoscopic findings in patients with dyspepsia

Serum immunoglobulin G (IgG) antibody tests are used extensively. We attempted to find out whether the titers of anti-Helicobacter pylori IgG antibody correlated with the degree of macroscopic gastrointestinal damage, the severity of antral gastritis, and the density of antral H. pylori colonization in symptomatic patients. Peripyloric antral biopsy specimens were obtained from 50 consecutive patients with dyspepsia undergoing upper gastrointestinal endoscopy. The macroscopic gastrointestinal damage and the histologic grades of antral gastritis were scored by a modified Lanza scale and Sydney system, respectively. In addition, the densities of antral H. pylori colonization were graded semiquantitatively. Serum IgG antibodies to H. pylori were measured by enzyme-linked immunosorbent assay. Thirty-six (M/F = 29/7) of the 50 patients had H. pylori infection documented by histologic examination or rapid urease test or both. Among the subjects, the IgG antibody titers to H. pylori correlated significantly with the grades of antral polymorphonuclear cell infiltration (p = 0.002) and antral bacterial density (p = 0.01) but not with endoscopic scores, the grades of mononuclear cell infiltration, mucosal atrophy, or intestinal metaplasia (p > 0.05). In addition, endoscopic scores also were found to be significantly correlated with antral bacterial density (p = 0.049) and the grade of polymorphonuclear cell infiltration (p = 0.012). We therefore conclude that high titers of IgG antibody to H. pylori in patients with dyspepsia indicate dense H. pylori colonization and severe antral polymorphonuclear cell infiltration. However, it cannot replace endoscopic examination to evaluate the degree of macroscopic gastrointestinal damage.

Anti-IgM-induced growth inhibition and apoptosis are independent of ornithine decarboxylase in Ramos cells

Ornithine decarboxylase (ODC) is a key enzyme involved in polyamine production and is thought to regulate growth and apoptosis in multiple cell systems. A potential link between ODC and growth may involve the action of an oncogene c-myc which is thought to transcriptionally regulate ODC. We have examined the involvement of ODC in anti-IgM-induced growth inhibition and apoptosis in Burkitt's lymphoma cells. Inhibitors of ODC such as difluoromethylornithine (DFMO) completely blocked ODC activity, resulting in growth inhibition but not apoptosis. Addition of putrescine, the product of ODC enzymatic action, to Ramos cells had only a minor effect on growth, did not cause apoptosis, did not augment or block anti-IgM-mediated growth inhibition and apoptosis, but did reverse DFMO-mediated growth inhibition. Anti-IgM treatment of Ramos cells, which markedly decreased c-myc mRNA and protein, caused a paradoxical increase in ODC mRNA level as well as ODC enzymatic activity and increased cellular levels of putrescine. DFMO and putrescine did not alter c-myc mRNA levels directly, nor did they have any affects on anti-IgM-mediated down-regulation of c-myc mRNA. TNF-alpha, which inhibited anti-IgM-mediated apoptosis, did not inhibit either anti-IgM or DFMO-mediated inhibition of growth. These agents were without effect on ODC activity itself or on the anti-IgM-mediated increase in ODC activity. From these studies we conclude that ODC inhibition affects growth but is unrelated to the induction of apoptosis. Both anti-IgM-mediated inhibition of growth and induction of apoptosis are independent of ODC. Thus two distinct pathways for growth regulation are present: one in which ODC and polyamines are important and the other cell surface receptor-mediated (sIg) which is independent of ODC and polyamines.

Expression of DNA topoisomerase II alpha and multidrug resistance p-glycoprotein in acute leukemia

BACKGROUND

Drug resistance is a major cause of treatment failure in acute leukemia. Overexpression of multidrug resistance gene and decreased activity of topoisomerase II alpha are suggested as two important mechanisms for this resistance.

METHODS

We used immunohistochemical method to determine the expressions of both topoisomerase II alpha (topo II alpha) and p-glycoprotein (gp-170) in bone marrow biopsy specimens from 68 cases of acute leukemia. Patients were divided into four groups: (1) leukemia cells with high score for topo II alpha and negative for gp-170; (2) leukemia cells with high score for topo II alpha and positive for gp-170; (3) leukemia cells with low score for topo II alpha and negative for gp-170; and (4) leukemia cells with low score for topo II alpha and positive for gp-170. The clinical responses were then followed as routine, and the clinical correlation was evaluated by analysis of variance and Pearson Chi-Square test.

RESULTS

The measure of the single parameter (either topo II alpha or gp-170 alone) did not show a significant difference in the overall survival. However, the complete response rate was much higher in the first group patients whose bone marrow reading score was high in topo II alpha and negative for gp-170 expression. Survival duration increased with the increase in the complete response rate.

CONCLUSIONS

Combined parameters of topo II alpha and gp-170 are more useful than any individual parameter for the prognosis of acute leukemia.

Prediction of recurrent choledocholithiasis by quantitative cholescintigraphy in patients after endoscopic sphincterotomy

BACKGROUND

Endoscopic sphincterotomy (EST) is widely used for the removal of stones from the bile duct, but stones recur in about one fifth of patients.

AIMS

To investigate hepatic clearance by quantitative cholescintigraphy (QC) in patients after EST and to discern the relationship between biliary emptying and stone recurrence.

METHODS

One hundred and forty nine patients who had EST and clearance of the bile duct for choledocholithiasis were selected. All patients were confirmed to have complete EST by sphincter of Oddi manometry and underwent QC soon after normalisation of liver function. Regular clinical follow up was performed for each patient.

RESULTS

During a mean 36 month follow up, 22 (14.8%) patients developed recurrent stones in the bile duct. Irrespective of the status of the gall bladder, patients with recurrent stones had a slower hepatic clearance of radioisotope during QC compared with patients without stone recurrence, but only the differences in cholecystectomised patients had statistical significance. After carrying out multivariate analysis, one parameter of QC, percentage clearance of maximal count at 45 minutes, was found to be the only significant factor for stone recurrence. All recurrent stones in the common bile duct were successfully removed at endoscopy.

CONCLUSION

Slower hepatic clearance as shown by QC is an important factor responsible for stone recurrence after sphincter ablation.

A Nonlinear Three-Dimensional Rupture Theory of Thin Liquid Films

A process of nonlinear three-dimensional rupture of thin liquid films is numerically analyzed for the first time. With the rupture time being successfully calculated, it has been possible to develop a more complete rupture theory for thin liquid films. In contrast to the linear analysis indicating the shortest rupture time of thin liquid films to be the same for both two- and three-dimensional rupture, the nonlinear analysis reveals that the latter proceeds faster than the former. In particular, among all three-dimensional disturbance modes, the symmetric one makes the thin liquid films rupture fastest. It is concluded that the rupture process develops at a point rather than along a line on thin liquid films.

Complete coding sequence of hepatitis C virus genotype 6a

Hepatitis C virus (HCV) genotype 6a is found in a restricted part of South East Asia, including Hong Kong, Macau and Vietnam. We determined the full length coding sequence of a type 6a isolate (EUHK2) obtained from a Hong Kong blood donor. The sequence of EUHK2 contained a single open reading frame coding for a polyprotein of 3018 amino acids, within the range of 3008 to 3037 for other HCV genotypes. The full length sequence of EUHK2 showed 30.3%-32.9% nucleotide (24.3%-29.4% amino acid) sequence divergence from genotypes 1-4, but only 27.7% (20.7% amino acid) divergence from JK046 ("type 11a"). These similarity values were intermediate between those of other HCV genotypes (minimum 28.4%) and between subtypes (maximum 25%). The close evolutionary relationship of EUHK2 with JK046 was further indicated by their grouping together by phylogenetic analysis.

Emergency banding ligation versus sclerotherapy for the control of active bleeding from esophageal varices

Active bleeding varices are a great challenge to endoscopists. In this study, we compared the short-term efficacy and safety of banding ligation with injection sclerotherapy in the arresting of active bleeding from esophageal varices. Seventy-one cirrhotic patients with active variceal bleeding were randomized to receive banding ligation (37 patients) or sclerotherapy (34 patients) immediately after endoscopic examinations. Primary success rate (bleeding stopped for 72 hours) was 97% in the ligation group and 76% in the sclerotherapy group (P = .009). The efficacy of ligation was similar to sclerotherapy in the control of oozing varices (100% vs. 89%, P = .23), whereas ligation was superior to sclerotherapy in the control of spurting varices (94% vs. 62%, P = .012). The requirement of vasoconstrictors after emergency endoscopic treatment was lower in the ligation group than in the sclerotherapy group (11% vs. 41%, P = .007). Treatment failure within 1 month was 8% in the ligation group vs. 30% in the sclerotherapy group (P = .02). Blood transfusion requirements were significantly lower in the ligation group than in the sclerotherapy group (3.2 +/- 1.2 vs. 4.5 +/- 1.8 units, P < .01). Rebleeding rate within 1 month was 17% in the ligation group and 33% in the sclerotherapy group (P = .19). Significant complications were encountered in 5% of the ligation group and 29% of the sclerotherapy group (P = .007). Mortality rates within 1 month were 19% in the ligation group and 35% in the sclerotherapy group (P = .19). Banding ligation and sclerotherapy were comparable in the arresting of oozing varices, whereas ligation was superior to sclerotherapy in the control of spurting varices. Patients treated with ligation required fewer vasoconstrictors and fewer transfusion units than patients treated with sclerotherapy. Furthermore, banding ligation was associated with a lower complication rate than sclerotherapy.

Detection and clinical features of hepatitis C virus type 6 infections in blood donors from Hong Kong

The genotype distribution of hepatitis C virus (HCV) was investigated in 212 viraemic blood donors from Hong Kong. A subset of the samples was investigated using three different genotyping assays to establish the accuracy of each in this population. These assays were restriction fragment length polymorphism (RFLP) of amplified 5' noncoding region (5'NCR) sequences, RFLP of the core region, and a serotyping assay using peptides from two antigenic regions of NS4. Genotypes detected in Hong Kong blood donors were 1a (6.2%), 1b (58.8%), 2a (1.4%), 2b (1.4%), 3a (1.9%), and 6a (27.0%). All genotyping assays produced concordant results. No evidence was obtained for the presence of type 6 group variants recently identified in Southeast Asia, other than type 6a. A serotyping assay based upon the detection of type-specific antibody to epitopes in NS4 produced similar results to the genotyping assays (98% concordance), but a reduced sensitivity (75%) compared with genotyping methods. Sequence variation in NS4 was not the cause of the reduced rate of detection of type 6 antibody in this population. Eighty-four percent donors infected with type 6a were male, compared to 75% donors infected with type 1b. The median alanine transaminase (ALT) level in type 6 infected donors was lower than in type 1b, (43.8 and 51.1 U/l, respectively) although these values were not statistically significant (P = 0.094). There was no significant difference between the ages of donors infected with types 1b and 6a. Risk factors for HCV infection in the blood donors included blood transfusion, intravenous drug abuse, and tattooing. A significantly greater number of donors infected with HCV-6a reported a history of drug abuse (66%) than donors infected with HCV-1b (7%).

Report on anti-Dib encountered in two Hong Kong Chinese

Two cases of anti-Dib, a rarely encountered antibody, were identified in serum samples referred by hospital blood banks during the past 13 months. Case 1 is a 41-year-old female who required blood for elective surgery. Case 2 is a premature infant suffering from mild neonatal jaundice on day 2 after birth. The anti-Dib in both cases exhibited marked dosage effect. The titer/score against Di(a+b+) and Di(a-b+) red blood cells (RBCs) in case 1 was 8/10 and 32/32, respectively, and in case 2, 4/18 and 32/46. The monocyte monolayer assay (MMA) also gave a similar pattern of results, being l5 percent and 100 percent reactive when tested with Di(a+b+) and Di(a-b+) RBCs in case 1, and 0.4 percent (within normal range) and l4.4 percent in case 2. The patient in case 1 underwent her operation without blood transfusion. The infant in case 2 was treated by phototherapy and subsequently recovered without the need for exchange transfusion.

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.

Detection and clinical features of hepatitis C virus type 6 infections in blood donors from Hong Kong

The genotype distribution of hepatitis C virus (HCV) was investigated in 212 viraemic blood donors from Hong Kong. A subset of the samples was investigated using three different genotyping assays to establish the accuracy of each in this population. These assays were restriction fragment length polymorphism (RFLP) of amplified 5' noncoding region (5'NCR) sequences, RFLP of the core region, and a serotyping assay using peptides from two antigenic regions of NS4. Genotypes detected in Hong Kong blood donors were 1a (6.2%), 1b (58.8%), 2a (1.4%), 2b (1.4%), 3a (1.9%), and 6a (27.0%). All genotyping assays produced concordant results. No evidence was obtained for the presence of type 6 group variants recently identified in Southeast Asia, other than type 6a. A serotyping assay based upon the detection of type-specific antibody to epitopes in NS4 produced similar results to the genotyping assays (98% concordance), but a reduced sensitivity (75%) compared with genotyping methods. Sequence variation in NS4 was not the cause of the reduced rate of detection of type 6 antibody in this population. Eighty-four percent donors infected with type 6a were male, compared to 75% donors infected with type 1b. The median alanine transaminase (ALT) level in type 6 infected donors was lower than in type 1b, (43.8 and 51.1 U/l, respectively) although these values were not statistically significant (P = 0.094). There was no significant difference between the ages of donors infected with types 1b and 6a. Risk factors for HCV infection in the blood donors included blood transfusion, intravenous drug abuse, and tattooing. A significantly greater number of donors infected with HCV-6a reported a history of drug abuse (66%) than donors infected with HCV-1b (7%).

Anti-IgM-mediated regulation of c-myc and its possible relationship to apoptosis

Anti-IgM treatment of Burkitt's lymphoma cells is followed by either growth arrest or induction of apoptosis. In this study we have explored the role of c-myc in these events. Our results in Ramos cells indicate the following. (a) The decline in c-myc mRNA occurs at about 4 h; inhibition of about 80% being observed. (b) The stability of c-myc message is involved since the half-life of c-myc mRNA is decreased from about 30 min in untreated cells to about 15 min following treatment with anti-IgM. In the presence of cycloheximide, a protein synthesis inhibitor, the half-life is increased to about 50 min and was unaltered by treatment with anti-IgM. (c) By contrast, nuclear run-on experiments indicated no change in transcription rates for c-myc message due to treatment with anti-IgM. (d) A decrease in c-myc causes apoptosis since specific repression of c-myc with antisense oligonucleotides decreases the levels of c-Myc, inhibits growth rate, decreases viability, and induces apoptosis. (e) Anti-CD40 inhibition of apoptosis occurs without alteration in anti-IgM-induced down-regulation of c-myc mRNA, suggesting that it acts distally to c-myc down-regulation. Other cell lines were also investigated. In Epstein-Barr virus (EBV)-positive cell lines (Daudi, Raji, and Namalwa), anti-IgM treatment for 24 h results in growth inhibition without induction of apoptosis. In EBV-negative cell lines (ST486 and CA46, as well as Ramos), a more heterogeneous pattern of responses to anti-IgM are observed. Ramos and ST486 cells both show growth inhibition and apoptosis upon anti-IgM treatment; CA46 cells shown only growth inhibition but not apoptosis. Anti-IgM causes a decline in c-myc mRNA levels in all of these lines, as well as in c-Myc protein level in the two lines investigated, Daudi and Ramos, regardless of apoptosis. Addition of antisense c-myc oligonucleotides to the cells reduced growth in both Daudi and Ramos cells lines, however it resulted in substantial apoptosis only in Ramos cells. These results suggest that anti-IgM destabilizes c-myc mRNA by a process that involves mRNA turnover, rather than transcription rates. However anti-IgM exerts differential effects in EBV-positive and EBV-negative cell lines. EBV-positive cells are uniformly resistant to apoptosis, while EBV-negative cell lines show a tendency to apoptosis but with exceptions. Growth inhibition can be uncoupled from apoptosis in EBV-positive cell lines, but not in those EBV-negative cell lines prone to apoptosis. Furthermore, down-regulation of c-myc message correlates with growth inhibition in these cells, but is an insufficient link to apoptosis. By contrast inhibition of apoptosis by anti-CD40 occurs even though c-myc mRNA is decreased.

TNF-alpha inhibits anti-IgM-mediated apoptosis in Ramos cells

We have examined the effects of tumor necrosis factor-alpha (TNF-alpha) as an inducer or modulator of necrosis and/or apoptosis in B cell lines. TNF-alpha does not induce either necrosis or apoptosis in EBV-positive or -negative cell lines, regardless of the culture conditions of the cells or the presence or absence of cytokines. By contrast anti-IgM induces apoptosis in two EBV-negative cell lines (Ramos and ST486) but not in EBV-positive cell lines. Since TNF receptor and CD40 belong to the TNF receptor superfamily and anti-CD40 is a known inhibitor of apoptosis, we tested for TNF-alpha's effects on the inhibition of apoptosis induced by anti-IgM. Our results indicate that TNF-alpha inhibits apoptosis induced by anti-IgM in Ramos cells but not in ST486. The effects are dose and time dependent; the degree of apoptosis achieved and the selectivity of the effect among cell lines are strikingly similar for both TNF-alpha and anti-CD40. Furthermore when both agents are tested together no additivity in the inhibition is observed. The inhibition of apoptosis is a direct effect of TNF-alpha and not a permissive effect of another cytokine, since it is observed in defined medium. Although anti-IgM induces both TNF-alpha secretion and TNF receptors in Ramos cells, the concentration of secreted TNF-alpha is too low to affect apoptosis. Inhibition does not involve perturbation of the cell cycle distribution of Ramos cells. Furthermore rapid induction of c-fos and the decrease in c-myc observed after anti-IgM treatment are both unaltered by TNF-alpha. Our results suggest that TNF-alpha is an inhibitor of apoptosis in Ramos cells, that its overall pattern of inhibition is similar to that of anti-CD40, and that both agents act at some point distal to the alteration of c-fos and c-myc by anti-IgM.

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.

Use of two 16S DNA targeted oligonucleotides as PCR primers for the specific detection of Salmonella in foods

A 16S DNA targeted polymerase chain reaction (PCR) method specific for the detection of Salmonella isolates with various serotypes was developed. The primers used for such a PCR method were 16SF1 and 16SIII. 16SF1 is the reverse and complementary strand of 16SI which has been shown to be able to hybridize with Salmonella and Citrobacter spp. 16III on the other hand, is able to hybridize with Klebsiella and Serratia spp. in addition to Salmonella. Although 16SF1 and 16SIII were not specific to Salmonella only, when they were used as PCR primers, only the Salmonella isolates could be specifically detected. The interference from Citrobacter, Klebsiella and Serratia spp. could be prevented. None of the other non-Salmonella isolates including strains of the family of Enterobacteriaceae closely related to Salmonella would generate the false-positive reaction. When this PCR system was used for the detection of Salmonella cells artificially contaminated in food samples, results obtained were satisfactory. A detection limit of N x 10(0) cells per assay could be obtained.

First case of haemolytic disease of the newborn due to anti-Mur in Hong Kong

The fifth child of a Hong Kong Chinese mother developed moderate jaundice, attributable to antibodies (anti-Mi) against antigenic determinants in GP.Mur (Miltenberger, class III) red cells. Both the father and the eldest sister were of the phenotype GP.Mur. Testing of maternal serum against a red cell panel including cells known to carry the antigenic determinants of some Miltenberger phenotypes revealed the presence of anti-Mur. This report documents the first case of haemolytic disease of the newborn (HDN) due to anti-Mur in Hong Kong.

Production of hematopoietic regulatory cytokines by peripheral blood mononuclear cells in patients with aplastic anemia

The aim of this study was to measure the level of cytokines produced by peripheral blood mononuclear cells (PBMNC) in patients with aplastic anemia (AA) and determine their effect on normal bone marrow (BM) colony growth. Thirty-five patients with AA and 21 normal controls were enrolled in the study. Medium conditioned by PBMNC of AA patients in the presence of phytohemagglutinin (PHA) was found to be suppressive to the clonal growth of normal BM cells. Thus, we further determined the presence in the PBMNC conditioned medium (CM) of inhibitory cytokines (macrophage inflammatory protein-1 alpha [MIP-1 alpha], transforming growth factor-beta 2 [TGF-beta 2], interferon-gamma [IFN-gamma], and tumor necrosis factor-alpha [TNF-alpha]) and stimulatory cytokines (granulocyte-macrophage colony-stimulatory factor [GM-CSF], interleukin-3 [IL-3], and stem cell factor [SCF]). The results show no significant difference between AA patients and normal controls in the spontaneous production of all cytokines by PBMNC. After PHA stimulation, the production of MIP-1 alpha, IFN-gamma, TNF-alpha, and GM-CSF significantly increased in the cultures of AA patients (p = 0.0009, 0.0002, 0.0022, and 0.0156, respectively). However, both TGF-beta 2 and SCF were undetectable in most of the tested samples. IL-3 was measured in the conditioned medium only after PHA stimulation, but without significant difference between the two groups (p = 0.67). Furthermore, the myelopoietic suppressing effect of AA-PBMNC CM could be significantly blocked by pretreatment with specific antibodies to the corresponding inhibitory cytokines (MIP-1 alpha, IFN-gamma, and TNF-alpha). After antibody neutralization, an apparent change occurred in the clonal growth of normal BM cells incubated with AA-PBMNC CM, resulting in colony enhancement of 205, 131, and 237% by anti-MIP-1 alpha, anti-IFN-gamma, and anti-TNF-alpha, respectively. These results suggest that overproduction of inhibitory cytokines, rather than underproduction of stimulating cytokines, may play a role in the progression of at least some patients with AA.

A case of hydrops fetalis, probably due to antibodies directed against antigenic determinants of GP.Mur (Miltenberger class III) cells

The GP.Mur (Miltenberger class III) phenotype was found to occur in about 6.3 percent of Hong Kong (HK) Chinese blood donors. The incidence of antibodies directed against antigenic determinants of GP.Mur cells (anti-Mi) among patients was 0.34 percent, similar to that in Taiwan Chinese. A case of hydrops fetalis probably attributable to maternal anti-Mi was encountered in an HK Chinese woman during her sixth pregnancy. The anti-Mi was potent (titer 512, score 99). It fixed complement and was a mixture of IgG1 and IgG3. Two biological assays, the monocyte monolayer assay and the chemiluminescence test, were strongly positive. The father was found to be heterozygous for the GP.Mur gene.

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.

Hemolytic transfusion reaction due to Rh antibodies detectable only by manual polybrene and polyethylene glycol technique

The authors report two cases of severe hemolytic transfusion reaction (HTR) attributable to Rh antibodies, which were not detectable by the saline indirect antiglobulin test (SIAT), low ionic strength saline solution technique (LISS), or two-stage enzyme (Enz) indirect antiglobulin test (IAT), but were readily detectable by the manual polybrene technique (MPT), MPT-IAT, and polyethylene glycol (PEG) IAT. With rare exceptions, Rh antibodies can usually be easily detected by the SIAT or Enz-IAT, and seldom cause intravascular HTR. The two cases in this report illustrate the value of the MPT and PEG-IAT in the detection of clinically significant Rh antibodies that would not otherwise be detectable by conventional methods.

Overproduction of inhibitory hematopoietic cytokines by lipopolysaccharide-activated peripheral blood mononuclear cells in patients with aplastic anemia

The aim of this study was to measure the level of cytokines produced by peripheral blood mononuclear cells (PBMNC) in patients with aplastic anemia (AA) and to determine their effect on the clonal growth of normal bone marrow (BM) cells. Twenty-one patients with AA and 11 normal controls were enrolled in this study. Medium conditioned by PBMNC of AA patients in the presence of lipopolysaccharide (LPS) was found to be suppressive to the colony growth of normal BM cells. Thus, we further determined the presence in the PBMNC-conditioned medium (CM) of both inhibitory cytokines: macrophage inflammatory protein-1 alpha (MIP-1 alpha), tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta 2 (TGF-beta 2), and interferon-gamma (IFN-gamma), and stimulatory cytokines: interleukin-3 (IL-3) and stem cell factor (SCF). Spontaneous production of MIP-1 alpha was higher in the AA patients than the normal controls (1887 +/- 174 pg/ml vs 1643 +/- 93 pg/ml), but the difference was not significant. After LPS stimulation, the production of MIP-1 alpha was markedly increased in the AA patients, and its level was significantly higher than that of the normal controls (2360 +/- 149 pg/ml vs 1517 +/- 92 pg/ml, p = 0.0022). The level of TNF alpha was also higher in the AA patients. However, IFN-gamma, TGF-beta 2, SCF, and IL-3 were not detectable in the PBMNC-CM of either AA patients or normals. The myelopoietic suppressing effect of AA-PBMNC-CM from each AA patient was significantly blocked by pretreatment with anti-TNF-alpha, resulting in a colony-forming enhancement of 174% +/- 12%. A similar effect was noted in six of 11 AA patients by pretreatment with anti-MIP-1 alpha. We conclude that TNF alpha and MIP-1 alpha can be overproduced by the PBMNC of some AA patients, which may play a role in the progression of AA.

Hepatocellular carcinoma with metastasis to right atrium--a report of three cases

Hepatocellular carcinoma (HCC) is one of the most common neoplasma in Taiwan. The tumor itself has the tendency of extension into the venous system, such as to the portal vein, hepatic vein and inferior vena cava (IVC), but intra-atrial metastasis is unusual. Antemortem diagnosis was difficult before the availability of two-dimensional echocardiography (2-DE). Sometimes, the first symptoms and signs are cardiogenic manifestations such as dyspnea on exertion, syncope, edema of the lower legs, and shock. Clinicians may mistakenly make the wrong diagnosis of heart failure. Because of this, we hereby report three cases of HCC with right intra-atrial metastasis to raise the physician's awareness. All three cases initially presented as right side heart failure. Imaging study revealed hepatocellular carcinoma with right intra-atrial metastasis. Two of the three cases died within one month after diagnosis.

Synergy between signal transduction pathways is obligatory for expression of c-fos in B and T cell lines: implication for c-fos control via surface immunoglobulin and T cell antigen receptors

Expression of the protooncogene c-fos is controlled by three main regulatory pathways involving kinase C, cAMP, and calcium. Kinase C mediates its effects via phosphorylation of serum response factor (SRF) which interacts with the serum response element (SRE); cAMP and calcium mediate their effects via phosphorylation of CREB (cAMP regulatory element binding protein) presumably by activation of a protein kinase A or calmodulin-regulated kinase. We have examined the function of these elements in Burkitt's lymphoma cells (Ramos and Daudi) as well as a T lymphocytic cell line (Jurkat). We have found that stimulation of any one of these pathways alone has little or no effect on c-fos induction. However, kinase C activation (PMA stimulation) combined with either cAMP (forskolin plus MIX) or calcium stimulation (ionophore) leads to greatly enhanced c-fos induction. By contrast, cAMP in the presence of calcium shows no synergy in c-fos induction. Okadaic acid augments PMA- as well as calcium-mediated activation of c-fos, and has little or no effect when combined with cAMP. The main difference between Ramos (B cells) and Jurkat (T cells) in the regulation of c-fos is that cAMP plus calcium is strongly synergistic in Jurkat and is without effect in Ramos. Analysis of AP-1 activity using gel mobility shift assays confirms that the requirements for synergy in c-fos mRNA induction are paralleled by requirements for synergy in induction of AP-1 activity. Signaling in B cells due to anti-Ig stimulation involves both kinase C activation and release of intracellular calcium, and results in c-fos mRNA induction. Our results indicate that synergy between the kinase C activation and calcium is needed for efficient c-fos induction since neither of these two alone induces c-fos well. That synergy of signaling pathways is relevant for the anti-Ig induction of c-fos is supported by the fact that cAMP-inducing agents and okadaic acid further enhance anti-Ig induction of c-fos. These results suggest that cell-specific patterns of synergy are an essential feature for c-fos induction and may be relevant for c-fos control through B and T cell antigen receptors.

Hydrosonography in the evaluation of colorectal polyps

Prewarmed saline enemas and transabdominal ultrasound (hydrosonography) were used to evaluate 17 consecutive children with rectal bleeding before colonoscopy. Twelve patients with polyps were identified (10 by ultrasound, 10 by endoscopy): these included multiple hyperplastic polyps (1), multiple polyps (1), solitary polyps (9), and pseudopolyps (1). Ultrasound identified 11 polyps in 10 patients, missing two patients with small polyps less than 0.5 cm in diameter. The polyps were hyperechoic ovoid masses fixed to the colonic wall, with a stalk (7), submucosal infolding (5), and intraluminal floating (5). There was one false positive. Colonoscopy was refused by one patient and failed to reach beyond the distal sigmoid in another following previous surgery for malrotation. Colonoscopy was superior in identifying finer mucosal detail (colitis, ulcers, proctitis, anal fissure) and in detecting smaller polyps (sessile polyps, hyperplastic polyps). Hydrosonography of the colon is a simple, relatively non-invasive procedure that provides an alternative, radiation-free examination of the whole colon before colonoscopy. It is complementary to colonoscopy in the management of rectal bleeding in children.

Use of NS-4 peptides to identify type-specific antibody to hepatitis C virus genotypes 1, 2, 3, 4, 5 and 6

The 5' end of the NS-4 protein of different genotypes of hepatitis C virus (HCV) is highly variable in nucleotide and inferred amino acid sequence, with frequent predicted amino acid substitutions between all six of the major HCV genotypes described to date. This region has been shown to be antigenic by epitope mapping, and elicits antibody in HCV-infected individuals with a detectable type-specific component. We have used this sequence data to specify branched peptides for an indirect binding/competition assay to detect type-specific antibody to each major genotype. A total of 183 out of 210 samples (87%) from blood donors and patients with chronic hepatitis C infected with genotypes 1 to 6 showed detectable type-specific antibody to NS-4 peptides that in almost all cases (> 97 %) corresponded to the genotype detected by a PCR typing method. These findings demonstrate the existence of major antigenic differences between genotypes of HCV, and indicate how infection with different variants of HCV may be detected by a serological test.

Induction of megakaryocytic differentiation in a newly established human leukemic cell line by 12-o-tetradecanoylphorbol-13-acetate

BACKGROUND

Biological studies on megakaryopoiesis have been hampered by the scarcity of megakaryocytes in normal bone marrow and difficulty in long term culture. Alternatively, leukemic cell lines with megakaryocytic differentiation potential may provide good models to counter these problems.

METHODS

Leukemic cells from a patient with acute megakaryocytic leukemia were put into long-term culture and established into a cell line which was designated as VGH-MK1. The VGH-MK1 cells were challenged with differentiation agents and/or cytokines, and the differentiation of these cells was examined using morphological, immunocytochemical and surface-marker studies.

RESULTS

Morphologically, VGH-MK1 cells had prominent nucleoli and basophilic cytoplasm with some protrusions, but large cells were occasionally seen. Under regular culture condition, the cells had a doubling time of 36-48 hours. The cloned cell line exhibited markers characteristic of megakaryoblasts after differentiation induction. Specifically, when stimulated with 12-o-tetradecanoylphorbol-13-acetate (TPA), cells became larger and had large or multinuclei. They were induced to express platelet glycoproteins GPIb (CD42b), GPIIb/IIIa (CD41), and GPIIIa (CD61) antigens, but not erythroid nor lymphoid markers. Platelet peroxidase (PPO) activity was also induced. Retinoic acid did not exhibit similar differentiation-inducing effects. In contrast, it counteracted the effects induced by TPA.

CONCLUSIONS

An unique human leukemic cell line, VGH-MK1, has been established here. It could be induced to exhibit some characteristics of megakaryocytic lineage, and may be an useful model for the biological studies of megakaryopoiesis.

Regulation of low-density lipoprotein receptors and assessment of their functional role in Burkitt's lymphoma cells

The status of low-density lipoprotein receptors (LDLR) in Daudi Burkitt's lymphoma (BL) cells was examined using a flow cytometric assay employing the fluorescent ligand DiI-LDL, and a radioligand-binding assay using [125I]LDL. The binding is concentration-and time-dependent; and is specific, as judged by its competitive displacement in the presence of unlabeled LDL, and inhibition by heparin, EGTA, and 4 degrees C incubation. The regulation of the receptor and its functional role were then explored. Our results suggest the following: (a) In sharp contrast to normal peripheral blood lymphocytes, the LDLR levels in BL cells are basally elevated when cultured in fetal bovine serum (FBS) medium. (b) In accord with normal peripheral blood lymphocytes, incubation in lipoprotein-deficient serum (LPDS) medium further up-regulates the level of the receptor in BL cells, and co-incubation with LDL or 25-hydroxycholesterol down-regulates the receptor level. The magnitude of the up-regulation is significantly smaller than in normal peripheral blood lymphocytes. (c) Northern blots using a plasmid-DNA probe for LDLR mRNA point to a similar pattern for message regulation as is observed in direct binding studies. (d) Although the LDLR level is constitutively high in BL cells, availability of LDL, unlike transferrin, is not a growth requirement since incubation of cells in LPDS medium does not prevent proliferation of these cells. (e) In contrast to anti-transferrin receptor antibody which results in apoptosis upon binding, anti-LDLR antibody does not inhibit growth or induce apoptosis. Our results suggest LDLR is expressed at a significantly higher level in BL cells than in normal peripheral blood lymphocytes. Although up-regulation and down-regulation of LDLR are observed, this applies only to a small population of LDLR. The bulk receptor population is significantly resistant to down-regulation. Furthermore, notable differences in the functional role of the LDLR are found relative to the transferrin receptor which is also up-regulated in the BL cells.

In-vitro activity of oxazolidinones against Mycobacterium avium complex

Options for treating disseminated Mycobacterium avium complex (MAC) disease have improved. However, efficacy is not always certain, resistance is common and rapidly bactericidal agents would improve efficacy and prevent resistance. Certain oxazolidinones were tested against MAC strains and inhibited growth at expected serum concentrations or lower. Activity correlated with hydrophobicity and one agent was bactericidal at concentrations two to five times greater than the MIC.

Development and evaluation of two novel oligonucleotide probes based on 16S rRNA sequence for the identification of Salmonella in foods

DNA sequence in the V3 to V6 region of the 16S rRNA gene of Salmonella enteritidis was determined. By comparison of this sequence with those of Escherichia coli and Proteus vulgaris obtained from GenBank/EMBL database, three oligonucleotides termed as 16S I, 16S II and 16S III were synthesized. Hybridization of these oligonucleotides with 325 Salmonella isolates and some non-Salmonella isolates including the Salmonella closely related species of the family of Enterobacteriaceae showed that 16S II could not be used as a Salmonella specific-probe. 16S I and 16S III hybridized with all the Salmonella isolates tested, the former also hybridizing with Citrobacter spp. and the latter hybridizing with Klebsiella pneumoniae as well as Serratia marcescens. Since enrichment of the target cells in food samples was usually required prior to the DNA hybridization assay, the interference from those non-Salmonella isolates could be prevented by enrichment by culturing in lactose-combined tetrathionate (CTET) broth followed by Gram-negative (GN) broth at 37 degrees C and/or 43 degrees C. Such a culture step could inhibit the growth of Klebsiella spp., Ser. marcescens and/or Citrobacter spp. and allowed the specific detection of Salmonella.

Dimethyl sulfoxide suppresses apoptosis in Burkitt's lymphoma cells

Previous reports have suggested that dimethyl sulfoxide (DMSO) may be a useful reversible G1 arresting agent for synchronizing Raji Burkitt's lymphoma cells (K. Takase et al. (1992) Cell Growth Differ. 3, 515-521; M. Sawai et al. (1990) Exp. Cell Res. 187, 4-10). We have therefore critically evaluated several aspects of DMSO's effects using Daudi and Ramos Burkitt's lymphoma (BL) cells. In BL cells starved in the presence or absence of DMSO for 4 to 6 days (approximately four to six doubling times), the following observations were noted: (A) Both Daudi and Ramos cells show increased cell synchrony accompanied by apoptosis when starved in RPMI 1640 supplemented with 10% fetal calf serum (FCS). Inclusion of 1.5% DMSO causes a diminution in apoptosis with minimal effects on synchrony. (B) Lowering the FCS concentration to 5% induces apoptosis. DMSO-mediated protection from apoptosis is observed in Daudi but not in Ramos. (C) When human serum (10%) is used instead of FCS, Daudi cells show no apoptosis and DMSO is without effect on cell cycle distribution. By contrast, Ramos cells show significant apoptosis, which is prevented by the inclusion of DMSO. (D) When starved in a chemically defined medium (AIM-V), both Daudi and Ramos cells show significant apoptosis. DMSO protects Ramos from apoptosis under these conditions. (E) Upon removal of DMSO, both Daudi and Ramos cells reenter the cell cycle but with significant apoptosis. (F) The protective effect of DMSO from apoptosis is observed in a narrow range of concentration between 1 and 2%. At higher concentration, DMSO itself induces apoptosis. These results suggest that DMSO itself prevents apoptosis, an effect which may present as an apparent effect on cell synchrony.

The first example of anti-Gya detected in Hong Kong

The incidence of anti-Gya is known to be extremely rare, and only a few examples have been reported in Japanese persons and in Caucasians. This case history reports the first example of anti-Gya detected in a Chinese person. The propositus is an 83-year-old male patient whose anti-Gya was revealed because of incompatibility of all units of blood tested by a saline indirect antiglobulin test (SIAT). Although the antibody had a titer of 512 by SIAT, 10 units of Gy(a+) red cells were transfused without any adverse effect.

Large granular lymphocyte leukemia. A study of nine cases in a Chinese population

Large granular lymphocyte (LGL) leukemia is a neoplastic disorder of lymphocytes that is characterized by the presence of prominent cytoplasmic granules, and involves the proliferation of at least two distinct cell types, T cells and natural killer (NK) cells. The authors report the clinical and pathologic features of 9 Chinese patients with LGL leukemia, who represented 14% of 64 cases of chronic lymphoproliferative disorders diagnosed at their centers in 3 years. Three different groups could be defined on immunophenotypic and clinical grounds. The first group of 4 cases were CD2+CD3+CD4-CD8+. With the exception of a pediatric case, these cases ran an indolent course that was similar to the T-cell LGL leukemia most common in Western patients. However, thrombocytopenia and pure red cell aplasia were more common in the patients in this study, which was similar to the experience in Japanese patients. The second group of two cases were CD2+CD3+CD4+CD8-, and appeared to have worse outcomes than the first group. The third group of 3 cases were CD2+CD3-CD4-CD8-CD56+. Although phenotypically similar to the NK-cell LGL leukemia reported in Western patients, these cases were clinically more aggressive than their Western counterparts. This study is the first to report comprehensively the different types of LGL leukemias in Chinese patients, and provides useful information on the similarities and similarities and differences of these disorders as compared to those cases in the West.

Flow cytometric evaluation of LDL receptors using DiI-LDL uptake and its application to B and T lymphocytic cell lines

Low density lipoprotein receptors (LDL-R) on Daudi Burkitt's lymphoma (BL) cells were assessed using fluorescent DiI (3,3'-dioctadecylindocarbocyanine iodide)-LDL and flow cytometric analyses. Receptor-specific binding of DiI-LDL is followed by internalization of the bound complex and lysosomal hydrolysis of the ligand. Increase in the fluorescence intensity per cell is hence used as a measure of DiI-LDL uptake and, implicitly, as an indication of LDL-R presence. Our results show that uptake was observed in > 98% of the Daudi cells, and the level of uptake was significant and clearly distinguishable from autofluorescence, suggesting that: (a) this assay is comparable to the iodinated LDL uptake assay, although the ED50 values for the ligands are different; (b) this assay is comparable to the flow-cytometric detection of LDL-R using a commercial antibody directed against the receptor itself, and superior to a similar assay based on an antibody directed against membrane-bound LDL; (c) LDL uptake could be monitored along with transferrin uptake, suggesting that multiple endocytic receptor activities can be concurrently studied; (d) DiI-LDL uptake can be examined along with fluorescein-conjugated anti-CD10, -CD19, and -CD71, with little cross-interference, offering the added advantage that endocytic uptake and phenotyping can be simultaneously monitored; (e) the expression of LDL-R is intrinsically elevated in diverse cell lines such as Daudi, Raji, Ramos, Jurkat, and WIL2-NS, but not in normal lymphocytes. Our results therefore indicate that flow cytometric analysis of DiI-LDL uptake has potentially useful applications in the detection and study of endocytic receptor LDL-R in B and T lymphocytic cell lines.

Krukenberg tumor in pregnancy with delivery of a normal baby: a case report

Successful termination of a pregnancy and delivery of a normal infant in a young woman with Krukenberg tumor is reported. This association has rarely been described previously. The persistent gastrointestinal symptoms mimicking the early nausea and vomiting of pregnancy mask the presentation of a tumor in the stomach. Growth of the fetus leading to abdominal distension masks the presence of the metastatic ovarian tumor in the pelvic cavity. Thus, early diagnosis of the tumor may be delayed. We emphasize the importance of differentiation between physiological morning sickness and unusual persistent gastrointestinal symptoms in pregnant women. Persistent unusual gastrointestinal symptoms need careful evaluation by panendoscopic examination.

Recombinant human granulocyte colony-stimulating factor infusion and/or autologous peripheral blood stem cell transplantation as a rescue for sequential high-dose combination chemotherapy: a preliminary report

BACKGROUND

Sequential cycles of combination chemotherapy with high-dose cyclophosphamide, etoposide and cisplatin (sHDCEP) can largely increase the total dose (TD) of drug delivered. If granulocyte colony-stimulating factor (G-CSF) and/or autologous peripheral blood stem cell (PBSC) rescue can shorten the duration of cytopenia between cycles of sHDCEP, the dose intensity (DI) can be increased as well. In order to explore the feasibility of delivering maximal TD and DI by administration of sHDCEP with G-CSF and/or PBSC rescue, this trial is undertaken to investigate the hematologic and nonhematologic toxicity observed with sHDCEP by G-CSF and/or PBSC rescue.

METHODS

Patients with refractory malignancy and well preserved physiologic function for whom no available therapy is likely to cure or prolong the survival were eligible for the study. Each cycle of high-dose chemotherapy consisted of: cyclophosphamide 5,000 mg/m2, etoposide 1,500 mg/m2 and cisplatin 150 mg/m2. G-CSF and/or PBSC were administered alternatively after each cycle as rescue for myelosuppression. The next cycle was given to patient who showed response to the previous cycle after recovery from toxicity for a maximal of 4 cycles.

RESULTS

Two cases of refractory malignancy with progressive disease were treated by sHDCEP for 7 cycles, including 4 cycles with G-CSF rescue, 2 cycle with PBSC rescue, and 1 cycle with G-CSF + PBSC rescue. In the 4 cycles rescued by G-CSF alone, we observed a slightly slower granulocyte and markedly prolonged platelet recovery in the subsequent cycle. By comparing the effect of G-CSF and/or PBSC rescue on hematologic recovery with the preceding cycle in the same patient, we found that G-CSF rescue provided faster granulocyte recovery than PBSC, but PBSC rescue provided faster platelet recovery than G-CSF. Rescue by larger number of PBSCs provided only faster platelet but not granulocyte recovery than rescue by adding G-CSF to a very small number of PBSCs. However, G-CSF plus the very small number of PBSCs provided shorter duration of both granulocytopenia and thrombocytopenia than rescue by G-CSF alone. The most common nonhematologic toxicity from sHDCEP included transient nausea, vomiting, diarrhea and mild impairment of liver function but we observed no significant or irreversible major organ damage. The side effect from PBSC collection was mild and toxicity from reinfusion of the thawed PBSCs was not obvious. Using G-CSF and/or PBSC rescue, sHDCEP was delivered repeatedly in no more than 4 weeks for the next-cycles except for patient 1 who had cycle 4 delayed because of prolonged platelet recovery by only G-CSF rescue in cycle 3.

CONCLUSIONS

Our initial experience has shown that the nonhematologic toxicity from sHDCEP, G-CSF and PBSC rescue was well tolerated. Prolonged platelet recovery after sequential cycles of HDCEP by only G-CSF rescue delayed the next cycle of chemotherapy. Although the next cycle was delivered within 4 weeks by only PBSC rescue, concurrent infusion of G-CSF and larger number of PBSCs should provide the most rapid hematologic recovery. Sequential high-dose chemotherapy administered by this model is likely to provide the maximal delivery of TD and DI, and is worthy of further clinical trials.

Sclerotherapy on liver cirrhosis with esophageal variceal bleeding: eight years of experience

BACKGROUND

Patients with liver cirrhosis usually die of hepatic failure and variceal bleeding. Successful treatment of the latter can reduce mortality. Sclerotherapy is one method often used. This study compared (a) the successful rate of acute bleeding control; (b) short- and long-term survival rate between those with and without treatment with sclerotherapy to evaluate the clinical benefit of sclerotherapy for liver cirrhosis patients with esophageal variceal bleeding.

METHODS

Between August 1983 and December 1991, 183 cirrhotic patients with esophageal variceal bleeding receiving endoscopic injection sclerotherapy (EIS) was compared with 123 patients without sclerotherapy treatment retrospectively. The severity of underlying liver disease was classified using a modified Child's classification. Sclerotherapy was done within 48 hours after active bleeding in the sclerotherapy-treated group, while the medical treatment group received Sengstaken-Blakemore (SB) tube or pitressin infusion only.

RESULTS

Successful rate of acute bleeding control was 81.63% (120/147) in the EIS group and 59.35% (73/123) in the medical treatment group. The worse the hepatic function of the patients, the lower the success of acute bleeding control in both groups. Fifty subjects (74.63%) had varices eradicated in 67 sclerotherapy treatment patients with regular follow-up. Patients receiving EIS had a better long-term survival than those without treatment. Benefit of EIS on long-term survival was more significant in Child B patients and less in Child C and Child A patients. Death from variceal bleeding was lower in the EIS group than in the medical treatment group (32% vs 62.6%). Complications of EIS were rare. Eight patients died of aspiration pneumonia, spontaneous bacterial peritonitis or acute renal failure after sclerotherapy, and most were Child B and C patients. Sixteen patients had esophageal stricture. Four needed dilatation treatment.

CONCLUSIONS

The sclerotherapy-treated group had a higher control rate of acute bleeding and lower mortality rate from esophageal variceal bleeding compared with the medical-treated group. The procedure prolonged long-term survival in Child B patients but did so less frequently in Child A and Child C patients. The incidence of complications was low. As a whole, EIS is a safe and efficient method for control of esophageal variceal bleeding.

Serum and ascitic concentration of C3, C4 and protein in cirrhotic patients with spontaneous bacterial peritonitis

BACKGROUND

Lower concentration of ascitic or serum complement (C3, C4) or protein has been reported to participate in the development of spontaneous bacterial peritonitis (SBP). In Taiwan, the etiology of hepatic cirrhosis is mainly post-hepatic and SBP is the common complication. This study aims to determine the role of protein and complements in the pathogenesis of SBP.

METHODS

119 cirrhotic patients were divided into two groups, 30 SBP and 89 non-SBP. The concentrations of ascitic and serum complement and protein were measured for comparison.

RESULTS

The ascitic and serum C3, C4 and protein levels were significantly lower (P < 0.05) in patients with SBP than in non-SBP patients. No significant differences were noted in the ascites/serum ratio of C3, C4 and protein in patient with or without SBP.

CONCLUSIONS

Low levels of ascitic and serum protein and complements, C3 and C4, may be prone to develop SBP in our patients mostly with post-hepatitic cirrhosis.

Do the reticulocyte maturation fractions and bone marrow reticulocyte count further help the classification of anemias?

BACKGROUND

Reticulocyte count plays a major role in anemic evaluation. The conventional method done by the manual supravital staining cannot subclassify the group of less than 2% of corrected reticulocyte count. The newly-developed flow cytometer provides different maturation fractions by measuring its fluorescent intensity. The reticulocytes are believed to shift to the circulation from the bone marrow earlier in more severe anemia. Therefore, the purpose of this study is to evaluate the role of reticulocyte maturation fractions and bone marrow reticulocyte in anemia classification.

METHODS

By using a fully automated counter, the roles of the reticulocyte with maturation and their shifting from bone marrow were evaluated in anemias. Different groups of subjects (243 in total) including aplastic, nutritional, and infiltrative anemias and anemia due to excess destruction and blood loss were studied. Each subject had bone marrow examination for morphologic diagnosis and reticulocyte evaluation.

RESULTS

Both the absolute count and the maturation fractions of reticulocytes showed significant difference among marrow infiltration, aplastic anemia, and hemolytic anemia. Both the absolute reticulocyte count and less mature fractions were lowest in aplastic group. The marrow reticulocyte counts and shift ratio to circulating blood added little benefit in the classification of anemias.

CONCLUSIONS

The automated reticulocyte count with maturation fractions helps classify anemias, particularly for those with low reticulocyte count by the manual method.

Survey of glycol ether use in Taiwan, 1991

Glycol ethers (including glycol ether esters) are a group of solvents with medium-high boiling points and low evaporation rates, possessing solvent characteristics of alcohol/ether functions (or ether/ester functions). They have been widely used in coatings and other industrial products for more than half a century. Recently, E-series glycol ethers have been found to show reproductive and teratogenic toxicity, and throughout much of the world they are being replaced by the so-called P-series glycol ethers. In responding to the impact of the worldwide transition from E- to P-series glycol ethers, the current status of glycol ether use in Taiwan was studied. This study focuses on the type and quantity of these solvents being used, worker and public knowledge about their hazards, and possible changes in government regulations being considered. In this study, we found that large quantities of E-series glycol ethers were imported and used in Taiwan. The best estimates are: 2-ME, 2,500 tons; 2-EE, 1,200 tons; 2-EEA, 5,000-8,000 tons; 2-BE, 8,000 tons annually in 1991. For P-series glycol ethers, only about 2,500 tons are being used. Lack of knowledge about the potential toxic effects of the E-series glycol ethers is very common among users, regulatory agencies, academic institutes, and the general public. It is hoped that the results of this study, along with educational efforts, government regulations, and provision of technical services, will help prevent Taiwan from becoming a dumping site for these toxic chemicals.

HLA antigen and antibody association in platelet-alloimmunized patients

The frequencies of HLA antigens were compared between 55 patients with and 38 patients without lymphocytotoxic antibodies formation after long-term platelet transfusions. Only HLA-B60 and B75 were found to manifest significant difference between these two groups. Patients with HLA homozygosity had a higher incidence of alloimmunization. Although most of the platelet alloantibodies were against HLA antigens of high frequency, the HLA-antibodies were induced at a rate different from the frequency of their corresponding antigens. The antibodies against the first and second HLA loci are of similar frequencies. In conclusion, the patients with HLA homozygous alleles have a higher incidence of platelet alloimmunization, and the antibody of certain specificities has higher rate of occurrence. These findings may be helpful in platelet-donor selection.

Sequence variability in the 5' non-coding region of hepatitis C virus: identification of a new virus type and restrictions on sequence diversity

We have analysed the pattern of nucleotide sequence variability in the 5' non-coding region (5' NCR) of geographically dispersed variants of hepatitis C virus (HCV). Phylogenetic analysis of sequences in this region indicated the existence of a new virus type, provisionally termed type 4, the identity of which was confirmed by further analysis of the more variable part of the HCV core protein coding region. The geographical distribution of HCV type 4 was distinct from that of other HCV types, it being particularly widespread in Africa and absent or rare in Europe and the Far East. Much of the variability in the 5' NCR appears to be constrained by a requirement for specific secondary structures in the viral RNA. In one of the most variable regions of the 5' NCR (positions -169 to -114), most of the nucleotide changes that are characteristic of different HCV types were covariant, with complementary substitutions at other positions. According to the proposed secondary structure of the 5' NCR, such changes preserved base pairing within a stem-loop structure, whereas the nucleotide insertions found in a proportion of 5' NCR sequences, including those of type 4, localized exclusively to the non-base-paired terminal loop. The specific nucleotide substitutions in the 5' NCR that differentiate each of the four HCV types can be detected by restriction enzyme cleavage, providing a rapid and reliable method for virus typing.

Multiple forms of the G protein-related beta subunit in Daudi lymphoblastoid cells

We have explored the forms of the G protein-related beta subunit which are present in Daudi lymphoblastoid cells. Northern blotting with labeled beta-1 and beta-2 probes indicates that two messages of 3.3 kb and 1.7 kb are present for both beta-1 and beta-2, implying that multiple forms of the beta subunit are present. Antibodies were raised against two peptides of the beta subunit (residues 1-23 and 127-145). Both antibodies detected subunits at 35 kDa and 31 kDa, of which the 35-kDa form predominates in the membrane fraction and the 31-kDa one in the cell cytosol. Crosslinking of the membrane fraction with the cleavable crosslinker (DTSSP) caused a simultaneous diminution in the 31-kDa form while increasing the amount of the 35-kDa form--a pattern which was reversed upon the reduction of these crosslinks with DTT. Studies of the soluble form indicate that this is truly a soluble protein since centrifugation at 200,000 x g for 2 h did not diminish the levels of the protein in the soluble fraction. Sedimentation analysis indicates that the soluble beta-homologue is found in fractions which overlap with those which contain the mu chain of immunoglobulin at a position clearly distinct from the expected positions of free mu or free beta. Our results suggest that at least two forms of a subunit which is closely related to, or identical with, the beta subunit of G proteins are present in Daudi cells.