The effect of age and prolonged cold ischemia times on the national allocation of cadaveric renal allografts

BACKGROUND

National sharing of cadaveric renal allografts for perfectly matched kidneys (0 antigen mismatch) has improved outcome in the recipients of these kidneys despite increasing cold storage times. However, there may be limits to outcome improvement of matched kidneys based on age and cold storage time.

MATERIALS AND METHODS

To determine if national sharing of kidneys based on matching improves outcome regardless of donor age and cold storage time, we evaluated the United Network for Organ Sharing (UNOS) Scientific Registry for all recipients of cadaveric kidney transplants between January 1, 1990 and July 31, 1998. We divided the recipients into four groups based on donor age and cold storage time. Group 1 comprised young donors (donor age <55 years) with average (<24 h) cold storage time; group 2, young donors with long (>/=24 h) cold storage time; group 3, older donors (donor age >/=55 years) with average cold storage time; and group 4, older donors with long cold storage time.

RESULTS

A total of 64,046 recipients were evaluated: 35,061 (55%) in group 1, 21,264 (33%) in group 2, 4308 (7%) in group 3, and 3414 (5%) in group 4. Early graft performance progressively decreased from group 1 to group 4. Delayed graft function (DGF: dialysis requirement in the first 7 days posttransplant) was 18, 29, 33, and 42% (P < 0.0001); serum creatinine at 3 years (in mg/dl) was 1.70 +/- 0.8, 1.73 +/- 0.9, 2. 31 +/- 1.0, and 2.42 +/- 1.1 (P < 0.0001); 1-year graft survival was 87, 84, 79, and 77% (P < 0.0001); and 3-year graft survival was 77, 74, 63, and 62% (P < 0.0001, for groups 1 and 2 vs groups 3 and 4, respectively). The trends in DGF persisted through the groups in 0 antigen mismatched kidneys.

CONCLUSIONS

Early function is adversely affected by prolonged cold storage, despite matching, in recipients of younger and older donor kidneys. Long-term function does not appear to be affected by prolonged cold storage. Recipients of kidneys from donors >/=55 years of age have significantly worse short- and long-term outcome and may not benefit from national sharing.

Gender differences in the patterns of coronary angiography and PTCA use in a university hospital in Taiwan

BACKGROUND AND PURPOSE

Coronary artery angiography (CAG) and percutaneous transluminal coronary angioplasty (PTCA) are important procedures for the diagnosis and treatment of patients with coronary artery disease. However, long-term trends in the frequency of CAG and PTCA use and their relation to gender have not been clearly determined in the Asian population. The purpose of this study was to investigate gender differences in the patterns of CAG and PTCA use in a university hospital in Taiwan during the period of 1983 through 1996.

METHODS

We studied the monthly data of all patients who underwent CAG or PTCA in a university hospital in Taipei from 1983 through 1996. A time series analysis was used to estimate gender differences in the patterns of CAG and PTCA use.

RESULTS

The frequency of CAG and PTCA increased significantly during this period. Before 1990, only a small number of patients underwent PTCA. However, this number increased steadily after 1990. Men were more likely to undergo CAG and PTCA than women. A time series analysis with fitted models was used to create an integrated moving average model. For CAG, the value of the estimated intercept for men was 2.5 times greater than that for women. In the PTCA series, the value of the intercept in men was 4.4 times greater than that in women. The patterns of trend change showed greater increases in men than in women, and a greater increase in the PTCA than in the CAG series. By transfer function modeling and intervention analysis, we found that the effect of CAG on the frequency of PTCA in men was 1.8 times greater than its effect in women. The estimated influence of the use of a new catheterization room (added in 1993) was 2.8 times greater in men than in women. The fitted model correlated well with the observed values in the next 12 months for both genders.

CONCLUSIONS

We concluded that women had fewer CAG and PTCA procedures than men, and the influence of CAG on the PTCA series was significantly higher in men than in women.

Genomic structure, expression, and chromosomal localization of the human glycine N-methyltransferase gene

The glycine N-methyltransferase (GNMT) gene encodes a protein that not only acts as an enzyme to regulate the ratio of S-adenosylmethionine to S-adenosylhomocysteine, but also participates in the detoxification pathway in liver cells. Previously, we reported that the expression level of GNMT was diminished in human hepatocellular carcinoma. In this study, the human GNMT gene was cloned and characterized. It contains six exons and spans about 10 kb. Instead of a TATA box, it has a transcriptional initiator located 801 bp upstream from the translation start codon. The gene was localized to chromosome 6p12 using fluorescence in situ hybridization. Northern blot analysis of 16 tissues from different human organs showed that GNMT was expressed only in liver, pancreas, and prostate.

A novel kinase, AATYK induces and promotes neuronal differentiation in a human neuroblastoma (SH-SY5Y) cell line

Apoptosis Associated Tyrosine Kinase (AATYK), a novel protein recently isolated from differentiating 32D mouse myeloid cells, contains a putative tyrosine kinase domain and several binding motifs for src homology 2 (SH-2) and src homology 3 (SH-3) domain containing proteins. We observed that AATYK is expressed in different regions of the brain. Although it might play a role in normal nervous system development by modulating apoptosis, little is known regarding its function in the brain or its intracellular localization and kinase activity. Recognizing its homology with Insulin like growth factor-I (IGF-I) receptor (IGF-IR) and the critical role of IGF-I in neuronal survival, we hypothesized that AATYK plays an important role in neuronal differentiation/apoptosis. To test this hypothesis, we transfected the human adrenergic neuroblastoma (NB):SH-SY5Y cells with AATYK cDNA under a tetracycline-repressible promoter and established stable cell lines that readily express AATYK on removal of tetracycline. AATYK immunoprecipitated from these cell lysates is an active kinase. Indirect immunofluorescent staining of the clones revealed AATYK to be localized in the cytoplasm. By itself, AATYK overexpression for short duration (2-3 days) did not induce differentiation in the stable SH-SY5Y clones. On the other hand, overexpression for longer periods (7-8 days) per se, significantly (P<0.05-0.001) increased the percent of differentiated cells as well as the neurite length. AATYK-induced differentiation was in the same range as the differentiation induced by agents like all-trans retinoic acid (RA), 12-O-Tetradecanoyl phorbol 13-acetate (TPA) and IGF-I. In addition, AATYK significantly promoted the neuronal differentiation induced by these agents. Our results demonstrate for the first time that AATYK is an active, non-receptor, cytosolic kinase which induces neuronal differentiation and also promotes differentiation induced by other agents in the SH-SY5Y cells.

Postcholecystectomy abdominal bile collections

HYPOTHESIS

The clinical syndromes caused by bile collections in the abdomen span a wide spectrum and their natural history and risks are not fully appreciated.

DESIGN

Analysis of 179 patients with bile fistulas after cholecystectomy, of which 154 patients had undrained bile collections.

OBJECTIVE

To characterize the manifestations and natural history of abdominal bile collections.

SETTING

A tertiary care teaching hospital.

PATIENTS AND METHODS

The clinical findings in 179 patients with bile fistulas resulting from iatrogenic laparoscopic bile duct injuries and other miscellaneous operations between 1990 and 1999 were analyzed. The group of main interest consisted of 154 patients with undrained bile collections. Of these 154 patients, 21% had serious complications, including sepsis and multiorgan failure. The data were analyzed to identify the variables associated with this undesirable outcome.

MAIN OUTCOME MEASURES

Symptoms, physical findings, course of illness, and laboratory and imaging findings.

RESULTS

The clinical manifestations of intra-abdominal bile collections were initially discounted in 77% of patients, so the problem went unsuspected for a variable and often lengthy period. Abdominal pain and tenderness (bile peritonitis) gradually developed in 18% of patients with bile ascites. There were no differences in the initial clinical findings in this group compared with those who did not develop peritonitis. Nineteen percent of patients with undrained bile collections experienced serious morbidity. The initial clinical findings did not differ in these patients compared with those with a less complicated illness. Serious illness, however, was associated with the following: (1) a longer period of undrained bile (15.4 vs 9.2 days, P=.04) and (2) a higher incidence of infected bile (45% vs 7%, P=.001).

CONCLUSIONS

(1) Prominent abdominal pain and tenderness developed in only 21% of patients with abdominal bile collections; (2) the symptoms caused by bile collections were often subtle and their significance was overlooked, which resulted in a delay in diagnosis; (3) the early clinical findings could not distinguish patients who did become critically ill from those who did not; and (4) seriously ill patients more often had delayed drainage and infected bile. Still, failure to drain a bile collection within just 5 days resulted in serious illness in a few patients. Surgeons must watch for the clinical manifestations of bile ascites after laparoscopic cholecystectomy. This diagnosis should be suspected whenever persistent bloating and anorexia last for more than a few days; failure to recover as smoothly as expected is the most common early symptom of bile ascites. If bile collections were promptly diagnosed and drained, the rate of serious illness resulting from this complication would decline.

Cerebral infarction in newborns: report of two cases

Neonates with cerebral infarction do not present with specific symptoms and the condition is usually insidious, so many atypical cases are not diagnosed properly during the neonatal stage. Normal neurological examination results may be found in newborns who have actually had a cerebral infarction insidiously. We present two newborns with cerebral infarction. One had clinical symptoms of seizures. Brain computed tomography showed a low-attenuated area and magnetic resonance angiography showed a decreased caliber and number of cerebral artery branches. The other had normal neurological examination results. He was referred to our hospital due to cyanosis. Brain sonography revealed a focal hyperechoic area and T2 weighted magnetic resonance image showed an increased signal intensity area. The incidence, etiologies, clinical and radiographic findings are also reviewed.

Fibronectin/fibroblast growth factor/cell matrix signaling pathways and reciprocal membrane interaction may be the regulators of cell growth and apoptosis in Trypanosoma musculi in co-cultures with fibroblasts

Trypanosoma musculi cultivated in medium containing serum alone or in the absence of fibroblasts in vitro were transformed into rounded, immotile cells, incapable of division and infectivity. Only in close contact with fibroblasts could the parasites survive and grow indefinitely. This report established the identity of the splenic 'sustentacular' cells as fibroblasts and utilized immunocytochemistry to demonstrate the putative cytoskeletal and membrane-associated molecules that may be involved in the control of growth and division, and apoptosis of T. musculi in vitro. The results indicated that cells that reacted intensely for fibroblast growth factor (FGF) also displayed a complex cytoskeletal system of F-actin bands underlying the plasma membrane of the fibroblast cell body and its numerous processes. Among the cytoskeletal and membrane glycoproteins, fibronectin, I-CAM, laminin, occludin, vinculin and desmin were most prominent. Fibronectin was most highly enhanced on the cell membrane and deposited as 'finger prints or tracks' on the extracellular culture surfaces. Transmission and scanning electron microscopy confirmed the intimate contact between trypanosomes and fibroblasts, however, neither membrane fusion or junctions were apparent. Our results suggested that a fibroblast-derived, membrane-associated factor appeared to be the putative growth regulator and apoptosis inhibitor in co-cultures of spleen-derived fibroblasts and T. musculi.

Telomerase activity in rat liver allografts

BACKGROUND

Telomerase activity in grafts may be involved in the alteration of cellular senescence after transplantation or its relevant immunological events.

METHODS

At the age of 20 weeks, donor livers harvested from DA (RT1a) were orthotopically transplanted into PVG (RT1c) or LEW (RT1(1)) rats. Rats having undergone orthotopic liver transplantation (OLT; DA-PVG) naturally overcome rejection, whereas all OLT (DA-LEW) rats die from acute rejection within 14 days. Telomerase activity in liver allografts was measured at various intervals post OLT.

RESULTS

At day 7 when the most severe rejection episode was observed in OLT (DA-LEW) and OLT (DA-PVG), the telomerase activity was significantly higher than in syngeneic OLT (DA-DA) rats, in which no rejection occurred. Telomerase activity in tolerogenic OLT (DA-PVG) livers remained elevated for at least 2 months.

CONCLUSION

These results suggest that telomerase activity in allogeneic OLT livers may reflect regenerating hepatocytes or activation of lymphocytes and/or hematopoietic stem cells associated with rejection or tolerance.

The role of 67Ga in the early detection of spinal epidural abscesses

In this study, we evaluated the role of 67Ga whole-body and single photon emission tomographic (SPET) imaging in the early diagnosis and lesion localization of spinal epidural abscess before confirmation by gadolinium-enhanced magnetic resonance imaging (MRI). Six patients with fever of unknown origin had a 67Ga whole-body scan, four of whom also underwent SPET imaging. For further confirmation of a spinal epidural abscess, gadolinium-enhanced MRI was performed in all patients. All patients had increased 67Ga uptake in a spinal or paraspinal area on the whole-body scan. They were later confirmed to have a spinal epidural abscess after gadolinium-enhanced MRI. Of these six patients, five underwent surgical drainage plus parenterally administered antibiotics, and had complete or partial recovery. One died before operation due to sepsis. In conclusion, we suggest performing a 67Ga whole-body survey as early as possible in patients with fever of unknown origin, fever and back pain and/or the spinal syndrome, before MRI is performed. If a spinal epidural abscess is strongly suspected, SPET is needed for further confirmation of spinal versus non-spinal and contiguous versus non-contiguous lesion(s). If MRI is unavailable, then 67Ga scintigraphy is a satisfactory method for investigating spinal epidural abscesses.

Pedal (99m)Tc-sulfur colloid lymphoscintigraphy in primary isolated chylopericardium

Primary isolated chylopericardium is a rare disorder in which chylous fluid accumulates in the pericardial space. In this case report of a 61-year-old man with chylopericardium, pedal (99m)Tc-sulfur colloid (SC) lymphoscintigraphy was performed after emergent pericardiocentesis, and when there was a recurrent massive pericardial effusion. The results showed that (99m)Tc-SC lymphoscintigraphy can clearly reveal the lymphodynamics in patients with primary isolated chylopericardium. This noninvasive investigation is valuable and can be easily performed either before or after pericardiocentesis.

Transcriptional regulation of endothelial nitric-oxide synthase by an interaction between casein kinase 2 and protein phosphatase 2A

We previously demonstrated that lysophosphatidylcholine up-regulated endothelial nitric-oxide synthase promoter activity by increasing Sp1 binding via the action of protein serine/threonine phosphatase 2A (Cieslik, K., Zembowicz, A., Tang, J.-L., and Wu, K.K. (1998) J. Biol. Chem. 273, 14885-14890). To characterize the regulation of basal endothelial nitric-oxide synthase promoter activity and the signaling pathway through which lysophosphatidylcholine augments endothelial nitric-oxide synthase transcription, we used a casein kinase 2 inhibitor coupled with immunoprecipitation to demonstrate that basal Sp1 binding and endothelial nitric-oxide synthase promoter activity were controlled by casein kinase 2 complexed with protein serine/threonine phosphatase 2A. Casein kinase 2 catalyzed protein serine/threonine phosphatase 2A phosphorylation thereby inhibiting its activity. Lysophosphatidylcholine selectively activated p42/p44 mitogen-activated protein kinase. Purified extracellular regulated kinase 2 blocked casein kinase 2 activity and increased protein serine/threonine phosphatase 2A activity, resulting in an increased Sp1 binding and endothelial nitric-oxide synthase promoter activity. These results indicate that Sp1 binding to its cognate site on the endothelial nitric-oxide synthase promoter and its transactivation of endothelial nitric-oxide synthase is regulated by post-translational Sp1 phosphorylation and dephosphorylation through a dynamic interaction between casein kinase 2 and protein serine/threonine phosphatase 2A.

Review of animal models in carotenoid research

Foods containing provitamin A carotenoids are the primary source of vitamin A in many countries, despite the poor bioavailability of carotenoids. In addition, epidemiologic studies suggest that dietary intake of carotenoids influences the risk for certain types of cancer, cardiovascular disease and other chronic diseases. Although it would be ideal to use humans directly to answer critical questions regarding carotenoid absorption, metabolism and effects on disease progression, appropriate animal models offer many advantages. This paper will review recent progress in the development of animal models with which to study this class of nutrients. Each potential model has strengths and weaknesses. Like humans, gerbils, ferrets and preruminant calves all absorb beta-carotene (betaC) intact, but only gerbils and calves convert betaC to vitamin A with efficiency similar to that of humans. Mice and rats efficiently convert betaC to vitamin A but absorb carotenoids intact only when they are provided in the diet at supraphysiologic levels. Mice, rats and ferrets can be used to study cancer, whereas primates and gerbils are probably more appropriate for studies on biomarkers of heart disease. No one animal model completely mimics human absorption and metabolism of carotenoids; thus the best model must be chosen with consideration of the specific application being studied, characteristics of the model, and the available funding and facilities.

The graded effect of hyperhomocysteinemia on the severity and extent of coronary atherosclerosis

It is not clear to what extent methylenetetrahydrofolate reductase (MTHFR) gene and hyperhomocysteinemia effect the severity and extent of coronary atherosclerosis in Asian populations. We examined the MTHFR genotypes and plasma homocysteine (HCY) concentrations in 192 Taiwanese and investigated their relationship with coronary artery disease (CAD), and the severity and extent of coronary atherosclerosis. The distribution of MTHFR genotypes was similar in 116 CAD patients and 76 non-CAD subjects. Homozygosity was noted in 8% of CAD patients and 13% of non-CAD subjects (P=0.33; 95% CI, 0. 2-1.6). The geometric mean of HCY values was higher in CAD patients (11.10+/-1.51 micromol/l) than in non-CAD subjects (9.21+/-1.55 micromol/l) (P=0.003). HCY levels were higher in patients with multi-vessel disease (P<0.05) or in patients with > or = 90% stenotic lesions (P=0.005), compared with non-CAD subjects. The CAD risks in the top two HCY quartiles (> or = 14.0 and 10.1-13.9 micromol/l) were 4.0 (95% CI, 1.7-9.2) and 3.2 (95% CI, 1.4-7.4) times higher than in the lowest quartile (< or = 7.9 micromol/l) (P=0.001 and 0.007, respectively). Linear regression analysis showed significant correlations between HCY concentrations and the severity and extent of atherosclerosis (P=0.0001 for both). In conclusion, hyperhomocysteinemia appears to have a graded effect on the risk of CAD as well as the severity and extent of coronary atherosclerosis. Our findings do not support the homozygous genotype of MTHFR as a genetic risk factor for CAD in this Taiwanese population. Perhaps a further study including assessment of vitamin status is needed to better clarify the relationship between MTHFR genotypes and CAD.

Protocerebral neurons inhibiting proliferation of corpus allatum cells in the cockroach, Diploptera punctata

A mitotic wave before an increase in juvenile hormone (JH) synthesis was observed in the corpora allata during each ovarian cycle in the cockroach Diploptera punctata and was shown subsequently to be inhibited by the brain until adult females mated. Each corpus allatum (CA) was innervated by groups of neurons in the contralateral pars intercerebralis (PI) and the ipsilateral pars lateralis (PL). In this article, a third set of neurons is identified that innervates the CA located extralaterally in the contralateral PL. The topography of the brain neurons innervating the CA was reconstructed from confocal optical sections after vital staining with two fluorescent carbocyanine dyes, 1,1'-dihexadecyl-3, 3,3',3'-tetramethylindocarbocyanine perchlorate [DiIC(16) (3)] and 3, 3'-dioctadecyloxacarbocyanine perchlorate [DiOC(18) (3)]. This provided information necessary to disconnect specific pathways within the brain of virgin females and to determine the effect on mitosis in the corpora allata and on the growth of oocytes. Disconnection of the CA from the PI neurons was followed by a prolonged period of moderate mitotic activity in the glands. Disconnection of the CA from PI and contralateral PL neurons was followed by a rapid wave of high mitotic activity in the CA similar to that observed after mating. The ipsilateral PL neurons did not appear to influence CA cell proliferation, because mitotic activity in glands was similar whether or not glands were connected to these neurons. Disconnection of the contralateral PI and/or ipsilateral PL neurons, but not the contralateral PL neurons, from the CA resulted in oocyte growth indicative of increased JH synthesis. The authors conclude that, whereas contralateral PI neurons inhibit both CA cell proliferation and JH synthesis, ipsilateral PL neurons affect only JH synthesis, and contralateral PL neurons modulate cell proliferation slightly only.

Precipitation of calcium oxalate monohydrate at phospholipid monolayers

Studies of calcium oxalate monohydrate (COM) precipitation at Langmuir monolayers of the phospholipids dipalmitoylphosphatidylglycerol (DPPG), dipalmitoylphosphatidylcholine (DPPC), and dipalmitoylphosphatidylserine (DPPS) are reported. The precipitation is heterogeneous and selective, with a majority of crystals orienting with the COM (101) face toward the monolayer interface for each phospholipid. The number density of COM crystals depends on the identity of the phospholipid monolayer, decreasing in the order DPPG > DPPS > DPPC. It was also found that COM precipitation increases as the surface pressure of the monolayer is lowered and with the addition of low levels (<0.1%) of cholesterol. The possibility that changes in monolayer fluidity influence COM attachment is discussed.

Excess mortality from hepatocellular carcinoma in an HCV-endemic township of an HBV-endemic country (Taiwan)

Taiwan is an endemic area of hepatitis B virus (HBV). All previous studies have concluded that HBV is the major cause of hepatocellular carcinoma (HCC) in Taiwan. An HBV- and hepatitis C virus (HCV)-endemic township, Tzukuan, in southern Taiwan has been identified with the prevalence of 24% for HB surface antigen (HBsAg) and 37% for anti-HCV antibodies. To elucidate the aetiology of HCC and impact of HCV in this township, we conducted a case-control study and compared HBV-related liver cancer mortality in Tzukuan and Taiwan as a whole. Based on cancer registration datasets of 2 medical centres from 1991 to 1995, we recruited 18 male and 9 female HCC cases from the study township. Their mean age (+/- standard deviation) was 60.3 (+/- 7.3) years. Randomly sampled from a community-based survey, 4 age- (+/- 2 years) and sex-matched residents were selected as community controls for each HCC case. The HBsAg carrier rate was 40.7% in cases and 25.0% in controls (P = 0.1). Anti-HCV positive rate was 88.9% in cases and 53.7% in controls (P = 0.008). Age-adjusted liver cancer mortality in Tzukuan (36.5 per 10(5)) was significantly higher than that of Taiwan as a whole (20 per 10(5)). Based on the HBsAg-positive rate among HCC patients (40.7% in Tzukuan and 77.4-86.6% in Taiwan), the estimated HBV-related liver cancer mortality was similar in Tzukuan (14.9 per 10(5)) and Taiwan (15.8-17.3 per 10(5)). We concluded that HCV was the major risk factor for excess liver cancer mortality in this HCV-endemic township of the HBV-endemic country.

DNA computing the Hamiltonian path problem

The directed Hamiltonian path (DHP) problem is one of the hard computational problems for which there is no practical algorithm on a conventional computer available. Many problems, including the traveling sales person problem and the longest path problem, can be translated into the DHP problem, which implies that an algorithm for DHP can also solve all the translated problems. To study the robustness of the laboratory protocol of the pioneering DNA computing for the DHP problem performed by Leonard Adleman (1994), we investigated how the graph size, multiplicity of the Hamiltonian paths, and the size of oligonucleotides that encode the vertices would affect the laboratory procedures. We applied Adleman's protocol with 18-mer oligonucleotide per node to a graph with 8 vertices and 14 edges containing two Hamiltonian paths (Adleman used 20-mer oligonucleotides for a graph with 7 nodes, 14 edges and one Hamiltonian path). We found that depending on the graph characteristics such as the number of short cycles, the oligonucleotide size, and the hybridization conditions that used to encode the graph, the protocol should be executed with different parameters from Adleman's.

Age, gender, and local geographic variations of viral etiology of hepatocellular carcinoma in a hyperendemic area for hepatitis B virus infection

BACKGROUND

There are etiologic variations of hepatocellular carcinoma (HCC) in different geographic areas. Taiwan is a hyperendemic area for hepatitis B virus (HBV) infection. Hepatitis C virus (HCV) infection also plays an important role in HCC development in Taiwan. Identification of local HCV-endemic areas is important to keep HCV from spreading. This study investigated the etiologic variations of HCC in different geographic areas of Taiwan.

METHODS

The authors evaluated the hepatitis B surface antigen (HBsAg) and antibodies to HCV (anti-HCV) status of 284 patients (232 male, 52 female) with HCC. They also evaluated the gender ratio and mean age of these patients.

RESULTS

The mean age of HBsAg positive patients was significantly lower than the mean age of HBsAg negative patients (52.6 +/- 12.3 vs. 61.3 +/- 11.2 years) (P < 0.05). The male-to-female ratio was 4.5:1 for all HCC patients, 7:1 for HBsAg positive HCC patients, and 2.8:1 for anti-HCV positive HCC patients. In Chaiyi County in southern Taiwan, the prevalence of anti-HCV in male HCC patients was 52%, significantly greater than that of Taiwan as a whole (27.6%) (P = 0.07). However, the prevalence of anti-HCV in male HCC patients in Taipei County in northern Taiwan was 8.7%, significantly less than that of Taiwan as a whole (P = 0.043). Of a total of 65 Chiayi-based HCC patients, 55.4% were anti-HCV positive and 46.2% were HBsAg positive. In the Chiayi area, results of multiple logistic regression showed that the HCC patients who were age 60 years or older or who were living in the city area both had highly HCV-related disease.

CONCLUSIONS

The mean age of patients with HBV-related HCC was significantly lower than that of patients with non-HBV-related HCC. The male-to-female ratio for patients with HBV-related HCC was significantly higher than that of patients with HCV-related HCC. The authors identified an area of Taiwan in which HCV-related HCC was prevalent.

Age, gender, and local geographic variations of viral etiology of hepatocellular carcinoma in a hyperendemic area for hepatitis B virus infection

BACKGROUND

There are etiologic variations of hepatocellular carcinoma (HCC) in different geographic areas. Taiwan is a hyperendemic area for hepatitis B virus (HBV) infection. Hepatitis C virus (HCV) infection also plays an important role in HCC development in Taiwan. Identification of local HCV-endemic areas is important to keep HCV from spreading. This study investigated the etiologic variations of HCC in different geographic areas of Taiwan.

METHODS

The authors evaluated the hepatitis B surface antigen (HBsAg) and antibodies to HCV (anti-HCV) status of 284 patients (232 male, 52 female) with HCC. They also evaluated the gender ratio and mean age of these patients.

RESULTS

The mean age of HBsAg positive patients was significantly lower than the mean age of HBsAg negative patients (52.6 +/- 12.3 vs. 61.3 +/- 11.2 years) (P < 0.05). The male-to-female ratio was 4.5:1 for all HCC patients, 7:1 for HBsAg positive HCC patients, and 2.8:1 for anti-HCV positive HCC patients. In Chaiyi County in southern Taiwan, the prevalence of anti-HCV in male HCC patients was 52%, significantly greater than that of Taiwan as a whole (27.6%) (P = 0.07). However, the prevalence of anti-HCV in male HCC patients in Taipei County in northern Taiwan was 8.7%, significantly less than that of Taiwan as a whole (P = 0.043). Of a total of 65 Chiayi-based HCC patients, 55.4% were anti-HCV positive and 46.2% were HBsAg positive. In the Chiayi area, results of multiple logistic regression showed that the HCC patients who were age 60 years or older or who were living in the city area both had highly HCV-related disease.

CONCLUSIONS

The mean age of patients with HBV-related HCC was significantly lower than that of patients with non-HBV-related HCC. The male-to-female ratio for patients with HBV-related HCC was significantly higher than that of patients with HCV-related HCC. The authors identified an area of Taiwan in which HCV-related HCC was prevalent.

Modulation of inducible nitric oxide synthase induction by prostaglandin E2 in macrophages: distinct susceptibility in murine J774 and RAW 264.7 macrophages

Prostaglandin E2 (PGE2) is the major cyclooxygenase metabolite in macrophages with complex proinflammatory and immunoregulatory properties. In the present study, we have compared the modulatory role of PGE2/cAMP-dependent signaling on induced nitric oxide (NO) production in two murine macrophages, J774 and RAW 264.7. With no effect on NO release by itself, PGE2 co-addition with lipopolysaccharide (LPS) resulted in a concentration-dependent enhancement in NO release and inducible NO synthase induction in J774, but not in RAW 264.7, macrophages. The potentiation effect of PGE2 in J774 cells was still seen when applied within 9 h after LPS treatment. Whereas RAW 264.7 macrophages release PGE2 with greater extent than J774 macrophages in response to LPS, indomethacin and NS-398, upon abolishing LPS-induced PGE2 release, caused a more obvious inhibition of NO release from J774 than RAW 264.7 cells. Thus, we suggest a higher positive modulatory role of PGE2--either endogenous or exogenous--on NO formation in J774 cells. Supporting these findings, exogenous PGE2 triggers cAMP formation in J774 cells with higher potency and efficacy. Of interest, dBcAMP also elicits higher sensitivity in potentiating NO release in J774 cells. We conclude that the opposite effect of PGE2/cAMP signaling on macrophage NO induction depends on its signaling efficacy and might be associated with the difference in endogenous PGE2 levels.

Susceptibility testing and clinical effect of fusidic acid in oxacillin-resistant Staphylococcus aureus infections

One hundred and six oxacillin-resistant Staphylococcus aureus (ORSA) isolates collected from various clinical specimens at Mackay Memorial Hospital during the period from 1997 to 1998 were tested. The MICs of fusidic acid against ORSA isolates were in the range of 0.06 microgram/mL to 4 micrograms/mL. There was only one ORSA isolate (0.9%) resistant to fusidic acid in this study. Twenty-four patients with ORSA infection were enrolled into the study between July 1997 to June 1998. Four patients without the evidence of sepsis received oral fusidic acid only. The other 20 patients with sepsis received intravenous glycopeptide first, and then the oral fusidic acid for 7 to 10 days. Oral fusidic acid was used for mild ORSA infection and achieved satisfactory clinical outcome. In severe ORSA infection, it was found that sequential therapy with fusidic acid had relapsed in three patients. We concluded that oral fusidic acid achieved a satisfactory outcome in our patients with mild ORSA infection. In such cases, fusidic acid may provide an effective alternative treatment of choice. The rare side effect of granulocytopenia and jaundice was noted in our case series. The side effect may be not so rare as previously thought, if it had been carefully looked for.

Additive effect of Sp1 and Sp3 in regulation of the ED-L1E promoter of the EBV LMP 1 gene in human epithelial cells

The ED-L1E promoter of the LMP 1 gene is a GC box-containing promoter. To test if Sp1/Sp3 are important for modulating ED-L1E promoter activity through the GC box, site-specific mutation and deletion constructs carrying a reporter gene were transfected into NPCTW076 and C33A cells. Results showed that deletion or mutation of the GC box abolished ED-L1E activity. Association of Sp1/Sp3 with the GC box was confirmed by electrophoretic mobility shift and supershift assays using Sp1- and Sp3-specific antibodies. Transfection of Sp1- and Sp3-expressing vectors into NPCTW076 and Sp-deficient Drosophila SL2 cells activated ED-L1E in a dose-dependent fashion and showed an additive effect. Data suggest that both factors may function as transcriptional activators and regulate the ED-L1E promoter in human epithelial cells.

The effects of dyslipidemia on left ventricular systolic function in patients with stable angina pectoris

Large-scale clinical trials have shown that long-term treatment with lipid-lowering therapy results in a significant reduction in the occurrence of heart failure among patients with coronary artery disease without previous evidence of congestive heart failure, suggesting dyslipidemia may have an adverse effect on left ventricular performance. To examine whether dyslipidemia has a detrimental effect on left ventricular systolic function and whether this effect is dependent on the corresponding severity of coronary atherosclerosis, 114 consecutive patients with stable angina and a positive exercise thallium-201 myocardial perfusion single-photon emission computed tomography were studied. All patients underwent measurement of serum lipid profiles, right-sided heart catheterization, left ventriculography, and selective coronary arteriography. Mean serum levels of total cholesterol and triglycerides were 4.5 and 1.4 mmol/l, respectively. In univariate analysis, a significant positive correlation between serum high-density lipoprotein (HDL) cholesterol and left ventricular ejection fraction (LVEF) (r = 0.49, P<0.0001) was found. Patients in the lower tertile of serum HDL cholesterol had a significantly lower mean LVEF than those in the upper tertile (55.9+/-15.2 vs. 72.8+/-6.8%, P<0.0001). Stepwise multiple linear regression analysis revealed that LVEF significantly correlated with HDL cholesterol (P<0.0001), the Gensini score (P = 0.008), and diabetes mellitus (P = 0.08) (r = 0.55, P<0.0001). In subgroup analysis of patients with angiographically normal coronary arteries, serum HDL cholesterol was still significantly associated with LVEF. The present study demonstrated an independent association between low HDL cholesterol and subclinical left ventricular systolic dysfunction in Chinese patients with stable angina whose serum levels of total cholesterol and triglycerides were relatively low. Moreover, this correlation remained significant even in patients with normal coronary angiograms, suggesting HDL cholesterol might influence left ventricular systolic performance through extra-atherosclerotic mechanisms.

Investigation of an outbreak of Pseudomonas putida using antimicrobial susceptibility patterns, pulsed-field gel electrophoresis of genomic DNA and restriction fragment length polymorphism of PCR-amplified rRNA operons

Seventeen Pseudomonas putida isolates were investigated which were collected from the urine specimens of 14 patients and one reflectrometer by comparing antimicrobial susceptibility patterns, pulsed-field gel electrophoresis (PFGE) of genomic DNA, and restriction fragment length polymorphism (RFLP) of PCR-amplified rRNA operons. Three susceptibility patterns were defined by testing 22 antimicrobial agents, with 14 isolates resistant to all agents. PFGE of XbaI-genomic DNA fragments divided the 17 isolates into 9 distinct types. One type, seen in 6 isolates showing identical patterns of approximately 35 fragments of 10 to 350 kb, was defined as the outbreak strain. Another 4 types, in a total of 6 isolates, were considered closely related to the outbreak strain; 2 types in 1 isolate each were possibly related to the outbreak strain; and 2 types in a total of 3 isolates were different from the outbreak strain. All 12 outbreak or closely related isolates were from patients in the surgical intensive care unit and a surgical ward, and were different from isolates in other wards, clearly indicating an outbreak of P. putida. Only two types were defined by the RFLP of 4.5 kb PCR-amplified rRNA operons; one type was seen in 15 isolates, while the other was seen in only 2 isolates. In conclusion, PFGE of genomic DNA is a highly discriminatory and reproducible method for epidemiological typing of P. putida.