On-line identification of trans- and cis-resveratrol by nonaqueous capillary electrophoresis/fluorescence spectroscopy at 77 K

This work presents a novel method for the accurate determining trans- and cis-resveratrol (3,5,4'-trihydroxystilbene) by nonaqueous capillary electrophoresis/fluorescence spectroscopy at 77 K. The proposed method permits not only the separation of resveratrol isomers, but also ensures that on-line spectra are readily distinguishable and unambiguously assigned. The experimental results also indicate that the effect of nonaqueous capillary electrophoresis buffer and low-temperature technique increase the detection limit by more than 150-fold.

Comparison of the APACHE II and APACHE III scoring systems in patients with respiratory failure in a medical intensive care unit

BACKGROUND AND PURPOSE

This retrospective study compared the capability of the Acute Physiology and Chronic Health Evaluation (APACHE) II and APACHE III scoring systems to predict outcome and determined the independent predictors of survival in these scoring systems for patients with respiratory failure in a medical intensive care unit (ICU).

MATERIALS AND METHODS

Seven hundred and eight patients with respiratory failure admitted to the medical ICU throughout a 9-year period were studied. Patients with an ICU stay of less than 24 hours, patients under 12 years of age, and burn and surgery patients were excluded. APACHE scores were calculated at 24 hours after admission. Student's t-test was used to compare the total APACHE scores of survivor and non-survivor groups. Multivariate logistic regression analysis was used to determine which variables were predictors of mortality. The discriminative power of APACHE scores to predict in-hospital mortality was studied by the area under the receiver operating characteristic curves of the APACHE II and APACHE III systems, respectively.

RESULTS

Both systems showed a significant association between higher scores and higher mortality. The APACHE II system under-predicted the actual hospital mortality rate. The APACHE III systems had a higher discriminative power (area 0.7462) than the APACHE II systems (area 0.6856; p < 0.05). The independent predictors of survival as assessed by APACHE II and III systems were respiratory rate, arterial oxygen pressure, oxygen gradient between alveoli and artery, serum creatinine concentration, and the presence of neurologic abnormalities.

CONCLUSIONS

The APACHE III systems has greater discriminative power than the APACHE II systems for predicting in-hospital mortality. The variables of oxygenation, mean artery pressure, respiratory rate, serum creatinine concentration, and Glasgow Coma Scale play important roles in predicting survival for patients with respiratory failure.

Noise and related events in a neonatal intensive care unit

The purposes of this study were to explore noise distribution, its timing, and sources of peak noise in the neonatal intensive care unit (NICU) of a University Hospital in Southern Taiwan. Two surveys on noise distribution and peak noise of the warmer bed were conducted. Noise at radiate heated beds located in the central sites of two areas, one near (Area A) and the other away from (Area B) the nursing station, were measured continuously for one week using an electronic sound-meter. Peak noise with a sound level of > 65 on the A-weighted decibel scale (dBA) and associated sources were recorded for 48 hours. Monitoring periods of peak noise consisted of a weekday and a day on the weekend randomly selected for Area A. Results showed that mean noise levels at the warmer bed in Areas A and B were 62 and 61.4 dBA on average. In over 70% of the total observation time for both areas the sound levels were > 59 dBA. The noise intensity was particularly high between 8 a.m. and 4 p.m. The noise level on the weekend was lower than that on weekdays. During the 48-hour observation period, 4994 peak noises were recorded. Eighty-six percent of these peak noises were within ranges of 65-74 dBA and 90% were human-related factors. The primary non-human related source was monitor alarms. Additionally, peak noises occurred primarily during the 8-11 a.m. and 2-4 p.m. hours on the weekdays and weekends. These results indicate that modifications of staff behavior, care procedures, and apparatus may reduce the noise levels in the NICU.

An indicator cell assay for detection of human cytomegalovirus based on enhanced green fluorescent protein

An indicator cell line (ML-UL54-EGFP) for the detection of human cytomegalovirus (HCMV) by a simple and direct method was developed. The stable line was constructed by introducing into mink lung cells an expression cassette that contains the enhanced green fluorescent protein (EGFP) reporter gene under the control of an HCMV-inducible promoter. The promoter was from the upstream region of the HCMV UL54 (pol) gene, an early gene promoter that is activated in the early phase of HCMV infection. Following infection with HCMV for 48 h, the stable line expressed well detectable level of the EGFP as observed under a fluorescence microscope. The sensitivity of the indicator cell assay is at least comparable with that of a plaque assay as assessed with a panel of HCMV strains. There were no detectable fluorescent cells after inoculations with several viruses other than HCMV, indicating high specificity. Analysis with flow cytometry revealed that the induced fluorescence from the infected cells was proportional to the titer of HCMV inoculated, making it possible to quantify HCMV infectious particles. In summary, the EGFP-based indicator cell line is of potential use for rapid detection and quantification of HCMV in clinical specimens.

Physiological adaptation of crop plants to flooding stress

When crop plants are subjected to soil waterlogging, or an anaerobic condition, their root and shoot systems respond differently. A variety of morphological and anatomical alterations develop in the root system. Reduction of the root respiration rate has been reported in both flooding-tolerant and intolerant species. Besides alcoholic fermentation, several diverse fermentative bypasses take place, which ameliorate the poisoning through excessive accumulation of specific metabolic intermediates. Root systems starved of oxygen are also poor providers of mineral nutrients for both themselves and the shoot systems. Stomatal closure and non-stomatal metabolic alterations are responsible for the reduction of leaf CO2 incorporation. Plant hormones are much involved in regulation of these physiological adaptations.

Chyloperitoneum: a postoperative complication after repair of tracheoesophageal fistula

Chyloperitoneum is rare condition that can occur in response to various pathologic process. The authors described a newborn baby who had chyloperitoneum after primary surgical repair of esophageal atresia with tracheoesophageal fistula (Gross type C). This probably resulted from iatrogenic damage of the thoracic duct during ligation of azygous vein resulting in leaking lacteal within the intestinal wall. Biochemical analysis of ascitic fluid, plasma, and milk formula for triglyceride and cholesterol level can differentiate neonatal gastric intestinal perforation.

Evidence for an association between polymorphism in the serotonin-2A receptor variant (102T/C) and increment of N100 amplitude in schizophrenics treated with clozapine

Using event-related potentials (ERPs), a reduction in the auditory N100, N200 and P300 amplitude has been found in schizophrenic patients and may represent some pathophysiological deficit. Therefore, we investigated whether the genetic variant of the serotonin-2A receptor is associated with ERP change after clozapine treatment in schizophrenic patients. Ninety-nine schizophrenic patients were included in the study. The results demonstrated that patients with 102C/C genotype have higher N100 amplitude than other patients after clozapine treatment. Our findings suggested that serotonin-2A receptor polymorphism may relate to clozapine response in schizophrenic patients. An objective and reliable tool like ERPs to assess patients' treatment response may afford more consistent results in pharmacogenetic studies.

Genome-wide hypomethylation in hepatocellular carcinogenesis

Aberrant genome-wide hypomethylation has been thought to be related to tumorigenesis. However, its mechanism and implications in hepatocellular carcinogenesis remain to be elucidated. Samples of hepatoma (hepatocellular carcinoma, HCC) and paired non-HCC liver tissues were obtained from 17 HCC patients. Normal liver tissues obtained from three individuals were used as controls. Compared with the paired non-HCC liver tissues, genome-wide 5-methylcytosine content in HCC was reduced in all of the tested HCC samples (P < 0.001). Conversely, genome-wide 5-methylcytosine content did not significantly differ among normal, noncirrhotic, and cirrhotic liver tissues. Moreover, the degree of reduced DNA methylation was related to late histopathological HCC grade (P = 0.005) and large tumor size (P = 0.079). Compared with the paired non-HCC liver tissues, expression of DNA methyltransferases DNMT-1, DNMT-3A, and DNMT-3B and the DNA methyltransferase-like gene, DNMT-2, was up-regulated in 53, 41, 59, and 47% of the HCC samples, respectively. Surprisingly, small amounts of LINE-1 retrotransposon transcripts were detected in HCC and non-HCC as well as normal liver tissues, and the expression levels were not significantly different in HCC compared with the paired non-HCC or normal liver tissues. Of interest, the 3' ends of these LINE-1 transcripts were truncated. Our findings suggest that genome-wide hypomethylation in HCC is a continuing process that persists throughout the lifetime of the tumor cells rather than a historical event occurring in precancer stages or in cell origins for HCC. Up-regulation of DNA methyltransferases might simply be a result of increased cell proliferation in cancer. In addition, our results did not support the hypothesis of activation of transposable elements in HCC via genome-wide hypomethylation.

A water-based triphenyltetrazolium chloride method for the evaluation of green plant tissue viability

A water-based 2,3,5-triphenyltetrazolium chloride (TTC) partitioning method using n-hexane for the evaluation of green plant tissue viability has been developed. Conventionally, the reduction of TTC to insoluble red-coloured triphenylformazan (TPF) has been used to detect seed, bud, leaf and cultured cell viability. However, the 95% ethanol used to extract TPF also extracts various pigments, such as chlorophyll, from plant tissues which interfere with the absorption of TPF at 485 nm. This new water-based method improves upon the current method by eliminating the interfering pigments in the hexane layer, and by minimising the non-enzymatic oxidation of the sample. When used to evaluate the tissue viability of chillstressed waxapple (Syzygium samarangense) plants, the refined method had a greater sensitivity than the electrolyte leakage method and thus provided a more precise assessment for the physiological state of various plant tissues.

Association analysis of polymorphism in the promoter region of the alpha2a-adrenoceptor gene with schizophrenia and clozapine response

There exists considerable evidence implicating the alpha (alpha) adrenergic system in the superior therapeutic effects of clozapine for the treatment of schizophrenia, as also its associated adverse hypersalivation side effect. It would seem plausible for variants of the adrenoceptors to be associated with the clozapine response. The present study tested the hypothesis that a biallelic polymorphism in the promoter region of the alpha2a-adrenoceptor gene confers susceptibility to schizophrenia, and is associated with a clozapine-induced (favorable) therapeutic response and/or a clozapine-induced hypersalivation. Ninety-seven treatment-resistant schizophrenic patients were assessed using the Brief Psychiatric Rating Scale before and after clozapine treatment. The results of clozapine treatment demonstrated that the alpha2a-adrenoceptor gene variants did not play a major role in the susceptibility, hypersalivation adverse effect or clozapine response of patients with schizophrenia. The polymorphism of the alpha2a-adrenoceptor gene investigated is not likely to play a major role in the pathogenesis of schizophrenic disorders or clozapine response, although the hypothesis that these genes are implicated in the cognitive deficit and polydipsia associated with schizophrenic disorders may, however, still warrant further study.

Mechanisms in the inhibition of neointimal hyperplasia with triflavin in a rat model of balloon angioplasty

RGD-containing peptides are able to inhibit the binding of ligands to certain beta3 integrins, such as alpha(IIb)beta3 and alpha(v)beta3, both of which are involved in neointimal hyperplasia. The present study was designed to elucidate the detailed mechanisms involved in the inhibition of neointimal hyperplasia with triflavin in a rat model of balloon angioplasty. Triflavin (0.25 mg x kg(-1) x d(-1)), an RGD-containing disintegrin, time dependently inhibited both neointimal hyperplasia and lumen occlusion after angioplasty in carotid arteries of rats. Furthermore, electron micrographs highlighted that SMCs were phenotypically different from the typical contractile, spindle-shaped SMCs normally seen in uninjured vessel walls. PDGF-BB was strongly produced in thrombus formation and neointimal SMCs after angioplasty, and triflavin significantly reduced PDGF-BB expression in vessel lumens and neointimal SMCs after angioplasty. Balloon angioplasty caused a significant increase of nitrate and cyclic guanosine monophosphate levels compared with levels found in sham-operated rats, and these were not significantly changed with infusion of triflavin (0.25 mg x kg(-1) x d(-1)). Furthermore, the plasma level of TXB2 obviously increased after angioplasty, and triflavin markedly suppressed the elevation of plasma TXB2 concentration. The results indicate that triflavin effectively prevents neointimal hyperplasia, possibly through the following 2 mechanisms. First, triflavin binds to alpha(IIb)beta3 integrin on platelet membranes, resulting in inhibition of platelet adhesion, secretion, and aggregation in injured arteries, followed by inhibition of TXA2 formation and PDGF-BB release from platelets. Second, triflavin may also bind to alpha(v)beta3 integrin on SMCs, thus subsequently inhibiting cell migration and proliferation. These results provide new insights into the mechanisms of neointimal hyperplasia and have significant implications for disintegrin therapy for the treatment of restenosis and atherosclerosis.

Effect of antenatal dexamethasone on the expression of endothelial nitric oxide synthase in the lungs of postnatal pups

Activities of endothelial nitric oxide synthase (eNOS) are developmentally regulated and its presence at birth may play a role in the transition of cardiopulmonary circulation. Antenatal dexamethasone (Dex) therapy accelerates fetal lung maturation. We speculate that Dex therapy may enhance pulmonary eNOS protein expression in the newborn. This article examines whether antenatal Dex therapy affected the expression of eNOS in the lungs of rat pups in the postnatal period. Time-dated pregnant Wistar rats were subjected to 2 doses of Dex (0.8 mg/kg, intramuscularly, daily) or equivalent volume of normal saline at the 18th and 19th gestational day and delivered naturally. The newborn pups were randomly assigned to 4 groups by age: days 1, 3, 5, and 7. After homogenization, abundance of eNOS protein in lungs was determined by Western blot analysis. There were 7 dams in each group. Mean body weights of the pups in the Dex group were lighter than those in the control at birth and remained stunted up to day 7 (5.68+/-0.47 g v 6.34+/-0.47 g, P <.01). However, there were no differences in wet lung weights and lung/body weight ratios between both groups in the study period. Abundance of eNOS protein expression decreased in both the control and Dex groups (P < .01). Pups that received antenatal Dex had 39% more in abundance of eNOS protein expression in lungs when compared to the control on day 1 (P < .05) but there were no differences between both groups from day 3 to 7. We conclude that antenatal Dex therapy enhances the abundance of eNOS protein expression in the lung at birth and could be a factor in improving respiratory functions in infants who received antenatal steroid therapy.

The role of lymphadenectomy in the radical nephrectomy for renal cell carcinoma

BACKGROUND

The value of lymphadenectomy in the management of renal cell carcinoma (RCC) remains controversial. Most would agree that lymphadenectomy (LD) provides accurate pathologic staging for prognostic data. The question remains whether there is any significant therapeutic benefit from extensive lymph node dissection with radical nephrectomy. The aim of this study was to compare outcomes in sampled lymphadenectomy (SLD) and extensive lymphadenectomy (ELD) with radical nephrectomy for RCC.

METHODS

One hundred and thirty-seven patients with RCC were enrolled in this study from Oct. 1982 to Dec. 1996. Eighty-one patients received radical nephrectomy with SLD (stage I: 43, II: 16, III: 22). Fifty-six patients received radical nephrectomy with ELD (stage I: 30, II: 11, III: 15).

RESULTS

The mean number of lymph nodes removed by SLD was 4 (ranged from 1 to 8). The mean number of lymph nodes removed by ELD was 16.1 (ranged from 9 to 32). Overall 5-year survivals for SLD in stages I, II and III were 98%, 80% and 38%, respectively. Overall 5-year survivals for ELD in stages I, II and III were 92%, 84% and 40%, respectively.

CONCLUSIONS

There is no significant therapeutic benefit from ELD in patients with RCC receiving radical nephrectomy.

HLA-DQA1 genotyping in patients with rheumatoid arthritis in Taiwan

To investigate the role of HLA-DQA1 genotypes and their interaction with HLA-DRB1 in the pathogenesis of rheumatoid arthritis (RA) in Taiwan, HLA-DQA1 was determined in 71 patients with RA and 108 healthy controls by SSP-PCR method. HLA-DRB1 and HLA-DQA1 were simultaneously detected in 55 RA patients and 101 healthy controls. PCR/SSOP method was used to determine the HLA-DRB1 genotypes, and the subtypes of HLA-DR4 were determined by cloning and sequencing. The phenotypic frequency of HLA-DQA1*0301 was significantly lower in RA than in controls, and, in contrast, the HLA-DQA1*0302 and DQA1*0303 were significantly higher in RA than in controls. The associations of DQA1*0301, *0302, and *0303 with RA were independent of DR4 and DRB1*0405. Moreover, the interactions between HLA-DR4 and HLA-DQA1*0302 or DQA1*0303 could enhance the development of RA. We also found that the prevalence of bone erosion and seropositivity of rheumatoid factor (RF) were significantly higher in HLA-DQA1*0303 positive RA patients than in healthy controls. HLA-DQA1*0302 and DQA1*0303 are the risk factors for susceptibility to RA, while HLA-DQA1*0301 is a protective factor. A synergistic effect for the susceptibility to RA can be found between HLA-DR4 and HLA-DQA1*0302 or DQA1*0303. We also found that the HLA-DQA1*0303 was related to bone erosion and seropositivity of RF in RA patients.

Study of anticipation in Chinese families with schizophrenia

The anticipation phenomenon is an important aspect in several genetic disorders in which the age at onset (AAO) decreases and the severity of illness increases in successive generations. This phenomenon has been reported in several schizophrenic family studies, and expanded repeat mutations are implicated. In the present study, we investigate the anticipation phenomenon in Chinese schizophrenic families. We compare the AAO between two generations of 38 unilinear schizophrenic families. Intergenerational comparisons show that the AAO was significantly earlier in the offspring generation (mean AAO, 22.2 years) than that in the parental generation (mean AAO, 31.0 years) (P < 0.001). When only including the offspring generation who married, the AAO difference between the two generations was not significant (28.4 years vs 31.0 years, P = 0.151). Our findings suggest that a selection bias in the parental group might greatly impact the study of anticipation in schizophrenia. Other unavoidable biases associated with these analyses are discussed in the text.

Genetic variants of the serotonin system and weight change during clozapine treatment

Clozapine-induced weight gain may impair health and affect patient compliance. The aim of this study is to investigate the relationship between the genetic variants of the serotonin system and clozapine-induced body weight change (BWC). Ninety-three treatment-resistant schizophrenic patients were weighed monthly for 4 months during clozapine treatment. At the conclusion of treatment, patients had gained an average of 2.4 kg body weight, with BWC ranging from -17.5 to +12.9 kg. The levels of the serotonin transporter variants, serotonin 2A, serotonin 2C and serotonin 6, demonstrated no statistically significant relationship to BWC. Patients with a lower initial body mass index demonstrated a greater weight gain associated with clozapine treatment. Further exploration of the neurotransmitters implicated in the antipsychotic-induced BWC is important in order to reduce the morbidity and noncompliance associated with weight gain.

Molecular topology of polycyclic aromatic carcinogens determines DNA adduct conformation: a link to tumorigenic activity

We report below on the solution structures of stereoisomeric "fjord" region trans-anti-benzo[c]phenanthrene-N2-guanine (designated (BPh)G) adducts positioned opposite cytosine within the (C-(BPh)G-C).(G-C-G) sequence context. We observe intercalation of the phenanthrenyl ring with stereoisomer-dependent directionality, without disruption of the modified (BPh)G.C base-pair. Intercalation occurs to the 5' side of the modified strand for the 1S stereoisomeric adduct and to the 3' side for the 1R stereoisomeric adduct, with the S and R-trans-isomers related to one another by inversion in a mirror plane at all four chiral carbon atoms on the benzylic ring. Intercalation of the fjord region BPh ring into the helix without disruption of the modified base-pair is achieved through buckling of the (BPh)G.C base-pair, displacement of the linkage bond from the plane of the (BPh)G base, adaptation of a chair pucker by the BPh benzylic ring and the propeller-like deviation from planarity of the BPh phenanthrenyl ring. It is noteworthy that intercalation without base-pair disruption occurs from the minor groove side for S and R-trans-anti BPh-N2-guanine adducts opposite C, in contrast to our previous demonstration of intercalation without modified base-pair disruption from the major groove side for S and R-trans-anti BPh-N6-adenine adducts opposite T. Further, these results on fjord region 1S and 1R-trans-anti (BPh)G adducts positioned opposite C are in striking contrast to earlier research with "bay" region benzo[a]pyrene-N2-guanine (designated (BP)G) adducts positioned opposite cytosine, where 10S and 10R-trans-anti stereoisomers were positioned with opposite directionality in the minor groove without modified base-pair disruption. They also are in contrast to the 10S and 10R-cis-anti stereoisomers of (BP)G adducts opposite C, where the pyrenyl ring is intercalated into the helix with directionality, but the modified base and its partner on the opposite strand are displaced out of the helix. These results are especially significant given the known greater tumorigenic potential of fjord region compared to bay region polycyclic aromatic hydrocarbons. The tumorigenic potential has been linked to repair efficiency such that bay region adducts can be readily repaired while their fjord region counterparts are refractory to repair. Our structural results propose a link between DNA adduct conformation and repair-dependent mutagenic activity, which could ultimately translate into structure-dependent differences in tumorigenic activities. We propose that the fjord region minor groove-linked BPh-N2-guanine and major groove-linked BPh-N6-adenine adducts are refractory to repair based on our observations that the phenanthrenyl ring intercalates into the helix without modified base-pair disruption. The helix is therefore minimally perturbed and the phenanthrenyl ring is not available for recognition by the repair machinery. By contrast, the bay region BP-N2-G adducts are susceptible to repair, since the repair machinery can recognize either the pyrenyl ring positioned in the minor groove for the trans-anti groove-aligned stereoisomers, or the disrupted modified base-pair for the cis-anti base-displaced intercalated stereoisomers.

Griseofulvin potentiates antitumorigenesis effects of nocodazole through induction of apoptosis and G2/M cell cycle arrest in human colorectal cancer cells

In this study, we demonstrate that apoptosis and G2/M cell cycle arrest were easily induced by treatment with the oral-antifungal agent, griseofulvin (GF). The mechanisms of GF-induced G2/M arrest were characterized as (a) induction of abnormal mitotic spindle formation, (b) elevation of cyclin B1/cdc2 kinase activity and (c) down-regulation of myt-1 protein expression. On the other hand, caspase 3 activation, Bcl-2 hyperphosphorylation and inhibition of the normal function of Bcl-2 associated with Bax were demonstrated to be the mechanisms of GF-induced apoptosis. DNA fragmentation and flow cytometry analyses demonstrated that combined treatment of GF with the cancer chemotherapeutic agent, nocodazole (ND), strongly potentiates the apoptotic effect and arrest of the G2/M cell cycle in 5 types of human cancer cells, but not in normal human keratinocytes (#76 KhGH). The combined treatment of GF and ND triggered the polymerization of purified tubulin in HT 29 but not in #76 KhGH cells. To further confirm these observations, the therapeutic efficacy was further examined in vivo by treating athymic mice bearing COLO 205 tumor xenografts, with GF (50 mg/kg), ND (5 mg/kg) or GF + ND. Combined treatment of GF and ND significantly enhanced the effect of ND, and led to cessation of tumor growth. These results suggest that chemotherapeutic agents (such as ND) administered in the presence of GF might provide a novel therapy for colorectal cancer.

Association study of apolipoprotein E epsilon4 with clinical phenotype and clozapine response in schizophrenia

Schizophrenic patients with the apolipoprotein E (APOE = gene; apoE = protein) epsilon4 allele exhibited lower psychosis scores than patients without the epsilon4 allele in previous reports. The present study tested the hypothesis that the APOE epsilon4 allele confers association with the clinical manifestations of schizophrenia or clozapine response. A total of 95 schizophrenic patients who were treatment resistant were included in the study. The results demonstrated that the presence of the APOE epsilon4 allele did not influence the response to clozapine in schizophrenic patients, neither was the baseline psychopathology related to the APOE epsilon4 allele. Given the multiple functions of the apoE protein in the brain, further study of the influence of APOE on CNS medication response is needed.

Development of a capillary electrophoresis-77 K luminescence detection system for online spectral identification

We have demonstrated that capillary electrophoresis (CE) can be easily interfaced with 77 K luminescence spectroscopy (LS) for separation and online spectral identification of structurally similar analytes. This novel CE-LS apparatus consists of a regular CE system, instrumentation for LS and a specially designed capillary Dewar. When the separating molecules traverse into the cryostat detection window, liquid nitrogen is added, freezing the separating analyte zones within the capillary. At low temperature, detection limits are improved via signal averaging and the inherent increase in quantum yield at 77 K. We present the first application of the CE-LS system to structural isomers (2,3- and 3,4-methylenedioxymethamphetamine) and stereoisomers (trans- and cis-resveratrol). With this approach, the CE-LS interfacing provides a sensitive, accurate, rapid, simple and economic methodology for analytical chemistry.

Multiple pleural nodules without effusion--a rare presentation of tuberculous pleurisy

We report a rare case of tuberculous pleurisy presenting with multiple pleural nodules without associated effusion or parenchymal lung lesions. A 62-year-old man had multiple discrete pleural nodules in the right hemithorax on chest radiography without any clinical symptoms. Thoracoscopic biopsy of the pleural nodules revealed a caseous granuloma with acid-fast bacilli. The patient received antituberculous therapy, with resolution of tuberculomas on chest film within 2 months. To our knowledge, only two similar cases have been previously reported in the English literature, and our observation should lead to broadening of the spectrum of the differential diagnosis of multiple pleural nodules.

Optimization of separation and migration behavior of chloropyridines in micellar electrokinetic chromatography

The separation and migration behavior of pyridine and eight chloropyridines, including three monochloropyridines, four dichloropyridines, and 2,3,5-trichloropyridine were investigated by micellar electrokinetic chromatography using either sodium dodecyl sulfate (SDS) as an anionic surfactant or SDS-Brij 35 mixed micelles. Various parameters such as buffer pH, SDS concentration, Brij 35 concentration and methanol content that affect the separation were optimized. Complete separation of these chloropyridines was optimally achieved with a phosphate buffer containing SDS (30 mM) and methanol (10%, v/v) at pH 7.0. The resolution and selectivity of analytes could be considerably affected by the addition of methanol and/or Brij 35 to the background electrolyte. The migration order of these chloropyridines depends primarily on their hydrophobicity. However, electrostatic interactions may also play a significant role in the determination of the migration order of the positional isomers of chloropyridines.

Mechanisms involved in the inhibition of neointimal hyperplasia by abciximab in a rat model of balloon angioplasty

Monoclonal antibodies raised against beta(3) integrin are able to inhibit the binding of ligands to certain beta(3) integrins such as alpha(IIb)beta(3) (glycoprotein IIb/IIIa complex) and alpha(v)beta(3) (vitronectin receptor) and as such are inhibitors of platelet aggregation and smooth muscle cell (SMC) migration, both of which are involved in neointimal hyperplasia. The present study was designed to explore the detailed mechanisms of abciximab (Reopro), a monoclonal antibody (mAb) raised against alpha(IIb)beta(3) integrin in neointimal hyperplasia. In this study, carotid arteries of Wistar rats were damaged, and neointimal hyperplasia and lumen occlusion was determined at different time points. Abciximab was administered intravenously by an implanted osmotic pump. Abciximab (0.25 mg/kg/day) time-dependently inhibited both neointimal hyperplasia and lumen occlusion after angioplasty in carotid arteries of rats. Furthermore, the electromicrographs highlighted that SMCs were phenotypically different from the typical contractile, spindle-shaped SMCs normally seen in uninjured vessel walls. Platelet-derived growth factor (PDGF)-BB was strongly produced in thrombus formation and neointimal SMCs after angioplasty, while abciximab significantly reduced PDGF-BB expression in vessel lumens and neointimal SMCs after angioplasty. Balloon angioplasty caused a significant increase of nitrate and cyclic GMP as compared with sham-operated rats. Infusion of abciximab (0.25 mg/kg/day) did not significantly change. Furthermore, the plasma level of thromboxane B(2) (TxB(2)) obviously increased after angioplasty, while abciximab markedly suppressed the elevation of plasma TxB(2) concentration. The results indicate that abciximab effectively prevents neointimal hyperplasia, possibly through the following 2 mechanisms: (1) Abciximab binds to alpha(IIb)beta(3) integrin on platelet membranes resulting in inhibition of platelet adhesion, secretion, and aggregation in injured arteries, followed by inhibition of thromboxane A(2) formation and PDGF-BB release from platelets. (2) Abciximab may also bind to alpha(v)beta(3) integrin on SMCs, thus, subsequently inhibiting cell migration and proliferation.

Griseofulvin potentiates antitumorigenesis effects of nocodazole through induction of apoptosis and G2/M cell cycle arrest in human colorectal cancer cells

In this study, we demonstrate that apoptosis and G2/M cell cycle arrest were easily induced by treatment with the oral-antifungal agent, griseofulvin (GF). The mechanisms of GF-induced G2/M arrest were characterized as (a) induction of abnormal mitotic spindle formation, (b) elevation of cyclin B1/cdc2 kinase activity and (c) down-regulation of myt-1 protein expression. On the other hand, caspase 3 activation, Bcl-2 hyperphosphorylation and inhibition of the normal function of Bcl-2 associated with Bax were demonstrated to be the mechanisms of GF-induced apoptosis. DNA fragmentation and flow cytometry analyses demonstrated that combined treatment of GF with the cancer chemotherapeutic agent, nocodazole (ND), strongly potentiates the apoptotic effect and arrest of the G2/M cell cycle in 5 types of human cancer cells, but not in normal human keratinocytes (#76 KhGH). The combined treatment of GF and ND triggered the polymerization of purified tubulin in HT 29 but not in #76 KhGH cells. To further confirm these observations, the therapeutic efficacy was further examined in vivo by treating athymic mice bearing COLO 205 tumor xenografts, with GF (50 mg/kg), ND (5 mg/kg) or GF + ND. Combined treatment of GF and ND significantly enhanced the effect of ND, and led to cessation of tumor growth. These results suggest that chemotherapeutic agents (such as ND) administered in the presence of GF might provide a novel therapy for colorectal cancer.

Neurological abnormalities in a knock-in mouse model of Huntington's disease

Mice representing precise genetic replicas of Huntington's disease (HD) were made using gene targeting to replace the short CAG repeat of the mouse Huntington's disease gene homolog (HDH:) with CAG repeats within the length range found to cause HD in humans. Mice with alleles of approximately 150 units in length exhibit late-onset behavioral and neuroanatomic abnormalities consistent with HD. These symptoms include a motor task deficit, gait abnormalities, reactive gliosis and the formation of neuronal intranuclear inclusions predominating in the striatum. This model differs from previously described HDH: knock-ins by its method of construction, longer repeat length and more severe phenotype. To our knowledge, this is the first knock-in mouse model of HD to show increased glial fibrillary acidic protein immunoreactivity in the striatum, suggesting that these mice have neuronal injury similar to that found early in the course of HD. These mice will serve as useful reagents in experiments designed to reveal the molecular nature of neuronal dysfunction underlying HD.

Enzymatic and Chemical Approaches for the Synthesis of Sialyl Glycoconjugates

In conclusion, either enzymatic or chemical approaches have their unique features and unavoidable disadvantages. Enzyme-catalyzed sialylations provide the desired sialo-glycosidic linkages in the two enzyme reactions (CMP-NeuAc synthetase and sialyltransferase) with exclusive stereoselectivity and high yield as long as the required sialyltransferase is available. High substrate specificity of the two enzymes is a limitation so that many unnatural glycoconjugates cannot be prepared enzymatically. As for chemical glycosylations of sialic acids, it is possible to introduce any modification in sialyl donor and acceptor, in addition to create special sugar linkages. Nevertheless, reducing the number of reaction steps (for preparing both donors and acceptors of glycosylation), and enhancing stereoselectivity, as well as reaction yield are still problems to be overcome.

Ketoconazole induces G0/G1 arrest in human colorectal and hepatocellular carcinoma cell lines

Ketoconazole is an oral-antifungal agent that has been used worldwide in the treatment of some hormone-dependent human cancer. In this study, we demonstrated that ketoconazole (20 microM) induced various types of human cancer cell growth arrest in the G0/G1 phase. Our results revealed that ketoconazole-induced growth arrest was more profound in COLO 205 and Hep G2 (with wild-type p53) than in HT 29 (p53 His(273) mutant) and Hep 3B (with deleted p53) cells. The protein levels of p53, p21/Cip1, and p27/Kip1 were significantly elevated by ketoconazole (10 microM) treatment in COLO 205 but not in HT 29 cells. The ketoconazole-induced G0/G1 phase arrest in COLO 205 cells was attenuated by p53-specific antisense oligodeoxynucleotides (20 microM) treatment. These results suggested that the p53-associated signaling pathway is involved in the regulation of ketoconazole-induced cancer cell growth arrest. By Western blot analysis, we demonstrated that cyclin D3 and CDK4 protein but not other G0/G1 phase regulatory protein levels were decreased by ketoconazole-treatment in both COLO 205 and HT 29 cells. Our study provides the basis of molecular mechanisms for ketoconazole in growth inhibition of human cancer cells and such results may have significant applications for cancer chemotherapy.

Helicobacter pylori culture and antimicrobial susceptibility from pediatric patients in Michigan

BACKGROUND

We recently observed a high failure rate in the eradication of Helicobacter pylori infection in children with 2-week triple therapy using lansoprazole, amoxicillin and clarithromycin. We performed a prospective evaluation of antral biopsies of all children subsequently diagnosed with H. pylori gastritis for culture and antimicrobial susceptibility assessment.

METHODS

All children with antral nodularity and/or an elevated anti-H. pylori IgG titer underwent antral biopsies for histology, urease test and culture while undergoing an upper endoscopy for routine indications. All positive cultures were tested for antimicrobial susceptibility by E-test for clarithromycin, amoxicillin, tetracycline and metronidazole.

RESULTS

Thirty-one children (16 male, 15 female) between 2 and 19 years of age were diagnosed with H. pylori gastritis by histology. However, culture was positive in only 22 of 31 (71%) patients. The E-test in vitro antimicrobial susceptibility testing revealed that 95.6% of the isolates were susceptible to amoxicillin, 59% to clarithromycin and 54.6% to metronidazole. There was no resistance to tetracycline.

CONCLUSION

Evaluation of antibiotic resistance profiles from pediatric patients from different geographic areas can help in optimizing therapeutic regimen to prevent treatment failures. Metronidazole and clarithromycin resistance is much higher in our pediatric population than reported in adults and could be a major contributor to failure of H. pylori eradication.

Intelligence and event-related potentials for young female human volunteer apolipoprotein E epsilon4 and non-epsilon4 carriers

The apolipoprotein E (APOE) epsilon4 allele is associated with late-onset Alzheimer's disease and cognitive function in aging normal populations. To study the effect of the presence of the epsilon4 allele on cognitive function, we compared intelligence-test scores and component values for event-related potentials for epsilon4 and non-epsilon4 carriers in a group of 134 young females. The results demonstrate modest increases in performance intelligence quotient (IQ) and N100 amplitude for epsilon4 carriers (P=0.038 and 0.068, respectively). Our findings suggest that cognitive impairment, associated with the presence of the epsilon4 allele, is age-dependent and thus not probable for young women. The higher performance IQ scores demonstrated for epsilon4 carriers require further exploration.

Origin of antimony segregation in GaInSb/InAs strained-layer superlattices

We show how cross-sectional scanning tunneling microscopy may be used to reconstruct the Sb segregation profiles in GaInSb /InAs strained-layer superlattices. These profiles are accurately described by a one-dimensional model parametrizing the spatial evolution of an Sb seed at the InAs-on-GaInSb interface in terms of two-anion-layer exchange. We argue that the segregation seed, which decreases from 2 / 3 to 1 / 2 monolayer when growth conditions are made less anion rich, has its origin in the Sb-bilayer reconstruction maintained during GaInSb epitaxy.

Diverticulosis of the appendix with diverticulitis: case report

Diverticulum of the appendix is rarely encountered. A case of appendiceal diverticulosis is described. A 46-year-old male patient was sent to our hospital with presentation of acute appendicitis-like symptoms. The appendix was removed by laparoscopic appendectomy, and it showed erythematous change with local peritoneal reaction and omental shift at the tip. Pathological examination revealed three diverticula in the appendix. One of them was inflamed but the appendix itself was not. All three diverticula were pseudodiverticula, lacking muscularis propria. The appendix in this case showed only focal inflammatory change, which differs from what occurs in acute appendicitis, where diffuse inflammation of the appendix is usually noted. In cases of an appendix with only focal erythematous change, minor lesions such as diverticulitis may be revealed by pathological examination, and an appendectomy is still warranted. Diverticulitis of the appendix cannot be differentiated from acute appendicitis preoperatively. Image studies including abdominal computed tomography scan, ultrasonography, and plain film cannot improve the diagnosis. To our knowledge, diverticulosis of the appendix has never been reported in Taiwan.

Mortality, morbidity, length and cost of hospitalization in very-low-birth-weight infants in the era of National Health Insurance in Taiwan: a medical center's experience

The impact of implementation of the National Health Insurance on the outcome, cost, and length of hospitalization of very-low-birth-weight (VLBW) infants is not clear in Taiwan. These data are important for the planning of medical care and regionalization in this area. This study was an attempt to examine these questions. We retrospectively collected mortality, morbidity, and length and cost of hospitalization data of VLBW (BW < 1500 g) infants between March 1995 and February 1998. There were totally 162 patients enrolled. The overall mortality rate was 21.6%; the birth weight (BW)-specific mortality rate was 72%, 31%, 19%, and 3% for infants with BWs of < 750 g, 750-999 g, 1000-1249 g, and 1250-1499 g, respectively. The incidence of morbidities were: respiratory distress syndrome (74%), patent ductus arteriosus (36%), necrotizing enterocolitis (9%), sepsis (42%), intraventricular hemorrhage (15%), retinopathy of prematurity (31%), failure to pass auditory brainstem response (ABR) (34%), and chronic lung disease (17%). The average length of hospitalization was 67.2 days, and the cost per infant was 62 x 10(4) NT dollars; 108 +/- 38 days, 73 +/- 32 x 10(4) NT dollars if BW < 750 g; 94 +/- 15 days, 99 +/- 35 x 10(4) NT dollars if BW 750-999 g; 66 +/- 23 days, 64 +/- 36 x 10(4) NT dollars if BW 1000-1249 g; and 43 +/- 14 days, 39 +/- 37 x 10(4) NT dollars if BW 1250-1499 g. In conclusion, VLBW infants are associated with high mortality and morbidity rates. They have long lengths and high costs of hospitalization, and therefore deserve attention in the implementation of the National Health Insurance and regionalization.

Functional implication of human serine/threonine kinase, hAIK, in cell cycle progression

Protein phosphorylation is involved in many biological activities and plays important roles in cell cycle progression. In the present study, we identified a serine/threonine kinase, hAIK, from human hepatic cells using degenerated polymerase chain reactions with a pair of primers derived from the highly conserved sequence in the catalytic domain of kinases. The full-length hAIK cDNA was then obtained, which contained 403 amino acids and was homologous to Drosophila Aurora2 and yeast Ipl1 proteins. Northern blotting analysis revealed that hAIK was highly expressed in the testis but not in other tissues. Expressions of hAIK drastically increased in cancer tissues/cell lines but not in fibroblasts or nontumorigenic cell lines. The recombinant hAIK protein phosphorylated itself and histone H1; this phosphorylation activity was totally abolished after a point mutation at the catalytic domain (hAIKm). During the interphase cell, hAIK was found mainly in the cytoplasm; during mitosis hAIK accumulated at the centrosomes. In addition, overexpression of hAIK in cancer cell lines (HEK293T and HeLa) appeared to inhibit cell cycle progression. None of these phenomena were observed in hAIKm whose kinase activity was rendered inactive. Our results suggest that hAIK protein/activity might modulate cell cycle progression by interacting with the centrosomes and/or proteins associated with these structures.

Rapid diagnosis and quantification of herpes simplex virus with a green fluorescent protein reporter system

A genetically modified cell line (Vero-ICP10-EGFP) was constructed for detection of herpes simplex virus (HSV) by a simple, rapid and direct method. The cell line was developed by stable transfection of Vero cell with a plasmid encoding the green fluorescent protein (GFP) driven by the promoter of the HSV-2 ICP10 gene. As early as 6 h after infection with HSV, fluorescence-emitting cells can be observed under a fluorescence microscope. A single infected cell emitting fluorescence can be observed with soft agar overlay by inverted fluorescence microscopy. No induction of detectable fluorescence was seen following infections with human cytomegalovirus (HCMV), varicella zoster virus (VZV), coxsackievirus A16 and enterovirus 71. Analysis by flow cytometry also demonstrated that intensity of the triggered fluorescence is proportional to the titer of HSV inoculated. Taken together, this novel GFP reporter system could become a useful means for rapid detection and quantification of HSV in clinical specimens.

The consistency and reliability of periodontal bone level measurements using digital scanning radiographic image analysis--a pilot study

The purpose of the present study was to evaluate the consistency and reliability of alveolar bone height measurement using digital scanning radiographic image analysis (DSRIA). A randomly selected (standardized paralleling technique) periapical radiographs of 20 molar teeth (10 maxillary molars and 10 mandibular molars) from 178 individuals with periodontitis were reporting or referred to the patient population of the dental clinics of the teaching hospital. Radiographic measurements were performed and read by two examiners, with a separation time of three weeks of different tooth groups and as established by double reading of 20 molar teeth in 10 individuals using the DSRIA. The calculating data of radiographic alveolar bone loss (RABL) measured and analyzed by the DSRIA for each molar group were compared based on the inter- and intra-examiners' data. The means and standard deviations were calculated to compare radiographs of the inter- and intra-examiners' groups. The reliability coefficients were computed to assess the consistency and reliability for each molar group. The results revealed that the intra- and inter-examiners' reliability coefficients ranged from 0.986 to 0.995 (p < 0.001, significantly different from 0). An excellent reproducibility was indicated in maxillary molar, mandibular molar and of both arches, respectively. It was concluded that the standard periapical radiograph using the DSRIA has the potential to be a valuable and reliable method in measuring linear alveolar bone defects caused by periodontitis.

An acidic amino acid cluster regulates the nucleolar localization and ribosome assembly of human ribosomal protein L22

The control of human ribosomal protein L22 (rpL22) to enter into the nucleolus and its ability to be assembled into the ribosome is regulated by its sequence. The nuclear import of rpL22 depends on a classical nuclear localization signal of four lysines at positions 13-16. RpL22 normally enters the nucleolus via a compulsory sequence of KKYLKK (I-domain, positions 88-93). An acidic residue cluster at the C-terminal end (C-domain) plays a nuclear retention role. The retention is concealed by the N-domain (positions 1-9) which weakly interacts with the C-domain as demonstrated in the yeast two-hybrid system. Once it reaches the nucleolus, the question of whether rpL22 is assembled into the ribosome depends upon the presence of the N-domain. This suggests that the N-domain, on dissociation from its interaction with the C-domain, binds to a specific region of the 28S rRNA for ribosome assembly.

Regeneration of PAPS for the enzymatic synthesis of sulfated oligosaccharides

This paper describes the study of 3'-phosphoadenosine-5'-phosphosulfate (PAPS) regeneration from 3'-phosphoadenosine-5'-phosphate (PAP) for use in practical syntheses of carbohydrate sulfates which are catalyzed by sulfotransferases. Among the regeneration systems, the one with recombinant aryl sulfotransferase proved to be the most practical. This regeneration system was coupled with a sulfotransferase-catalyzed reaction, using a recombinant Nod factor sulfotransferase, for the synthesis of various oligosaccharide sulfates that were further glycosylated using glycosyltransferases.

Association study of a functional serotonin transporter gene polymorphism with schizophrenia, psychopathology and clozapine response

Serotonin is implicated in the pathogenesis of schizophrenia. Following serotonin release, the serotonin transporter (5-HTT) is the major determinant of serotonin inactivation. The present study tested the hypothesis that a biallelic polymorphism in the 5' regulatory region of the 5-HTT gene (5-HTTLPR) confers susceptibility to schizophrenia, association with the clinical manifestations of schizophrenia or clozapine response. 90 treatment-resistant schizophrenic patients were assessed using the Brief Psychiatric Rating Scale before and after clozapine treatment. The results demonstrated that the 5-HTTLPR variants did not play a major role in the susceptibility, clinical manifestations or clozapine response in schizophrenia.

Major hematological diseases associated with cleft lip and palate

OBJECTIVE

Cleft lip and palate is among the most common congenital anomalies. Its association with major blood disorders has rarely been reported. The purpose of this study was to report two patients who had major blood diseases associated with cleft lip and palate.

PATIENTS AND RESULTS

From June 1995 to December 1997, there were 2700 patients with cleft lip, cleft palate, or both who received treatment at Chang Gung Memorial Hospital. Two of them were found to have major hematological disorders. In both cases, the disorder was detected by preoperative blood cell counts and white cell differentiation. Case 1 was a 21-year-old woman patient with repaired right cleft lip. She was admitted for alveolar bone grafting and closure of oronasal fistula. Abnormal presentation of blast cells was found, and subsequent bone marrow study confirmed acute lymphocytic leukemia. Case 2 was a 26-year-old man with left secondary cleft lip nasal deformity scheduled to receive staged reconstructive operations. An elevated platelet count was found and subsequently confirmed to represent essential thrombocytosis. In both cases, reconstructive operations for the cleft-related deformities were performed.

CONCLUSIONS

Association of major hematological disorders and cleft lip, palate, or both is rare and is reported herein.

Protein N-arginine methylation in subcellular fractions of lymphoblastoid cells

Arginine methylation in RNA-binding proteins containing arginine- and glycine-rich RGG motifs is catalyzed by specific protein arginine N-methyltransferase in cells. We previously showed that lymphoblastoid cells grown in the presence of an indirect methyltransferase inhibitor, adenosine dialdehyde (AdOx), accumulated high level of hypomethylated protein substrates for the endogenous protein methyltransferases or recombinant yeast arginine methyltransferase [Li, C. et al. (1998) Arch. Biochem. Biophys. 351, 53-59]. In this study we fractionated the lymphoblastoid cells to locate the methyltransferases and the substrates in cells. Different sets of hypomethylated methyl-accepting polypeptides with wide range of molecular masses were present in cytosolic, ribosomal, and nucleus fractions. The methylated amino acid residues of the methyl-accepting proteins in these fractions were determined. In all three fractions, dimethylarginine was the most abundant methylated amino acid. The protein-arginine methyltransferase activities in the three fractions were analyzed using recombinant fibrillarin (a nucleolar RGG protein) as the methyl-accepting substrate. Fibrillarin methylation was strongest in the presence of the cytosolic fraction, followed by the ribosomal and then the nucleus fractions. The results demonstrated that protein-arginine methyltransferases as well as their methyl-accepting substrates were widely distributed in different subcellular fractions of lymphoblastoid cells.

Synthesis and structure determination of 6-methylbenzo[a]pyrene-deoxyribonucleoside adducts and their identification and quantitation in vitro and in mouse skin

Activation of the moderate carcinogen 6-methylbenzo[a]pyrene (6-CH(3)BP) by one-electron oxidation to form DNA adducts was studied. Iodine oxidation of 6-CH(3)BP in the presence of dGuo produces BP-6-CH(2)-N(2)dGuo, BP-6-CH(2)-N7Gua and a mixture of 6-CH(3)BP-(1&3)-N7Gua, whereas in the presence of Ade the adducts BP-6-CH(2)-N1Ade, BP-6-CH(2)-N3Ade, BP-6-CH(2)-N7Ade and 6-CH(3)BP-(1&3)-N1Ade are obtained. Furthermore, for the first time an aromatic hydrocarbon radical cation afforded an adduct with dThd, the stable adduct BP-6-CH(2)-N3dThd. Formation of these adducts indicates that the 6-CH(3)BP radical cation has charge localized at the 6, 1 and 3 position. When 6-CH(3)BP was activated by horseradish peroxidase in the presence of DNA, two depurinating adducts were identified, BP-6-CH(2)-N7Gua (48%) and 6-CH(3)BP-(1&3)-N7Gua (23%), with 29% unidentified stable adducts. In the binding of 6-CH(3)BP catalyzed by rat liver microsomes, the same two depurinating adducts, BP-6-CH(2)-N7Gua (22%) and 6-CH(3)BP-(1&3)-N7Gua (10%), were identified, with 68% unidentified stable adducts. In 6-CH(3)BP-treated mouse skin, the two depurinating adducts, BP-6-CH(2)-N7Gua and 6-CH(3)BP-(1&3)-N7Gua, were identified. Although quantitation of these two adducts was not possible due to coelution of metabolites on HPLC, they appeared to be the major adducts found in mouse skin. These results show that 6-CH(3)BP forms depurinating adducts only with the guanine base of DNA, both in vitro and in mouse skin. The weaker reactivity of 6-CH(3)BP radical cation vs. BP radical cation could account for the weaker tumor-initiating activity of 6-CH(3)BP in comparison to that of BP.

Antiplatelet activity of Staphylococcus aureus lipoteichoic acid is mediated through a cyclic AMP pathway

In this study, Gram-positive Staphylococcus aureus lipoteichoic acid (LTA) dose dependently (0.1-1.0 microg/mL) and time dependently (10-60 min) inhibited platelet aggregation in human platelets stimulated by agonists (i.e., thrombin and collagen). LTA also dose dependently inhibited intracellular Ca(2+) mobilization in human platelets stimulated by collagen. In addition, LTA (0.5 and 1.0 microg/mL) dose dependently increased the formation of cyclic AMP but not cyclic GMP in platelets. LTA (0.5 and 1.0 microg/mL) did not significantly increase the production of nitrate within a 10-min incubation period. Rapid phosphorylation of a platelet protein of M(r) 47,000, a marker of protein kinase C activation, was triggered by PDBu (0.03 microM). This phosphorylation was dose dependently inhibited by LTA (0.5 and 1.0 microg/mL) within a 10-min incubation period. Furthermore, LTA (0.5 and 1.0 microg/mL) also inhibited platelet aggregation induced by PDBu (0.03 microM) in human platelets. These results indicate that the antiplatelet activity of LTA may be involved in the increase of cyclic AMP, leading to inhibition of intracellular Ca(2+) mobilization and protein kinase C activity. Therefore, LTA-mediated alteration of platelet function may contribute to bleeding diathesis in septicemic and endotoxemic patients.

Chromosomal changes and clonality relationship between primary and recurrent hepatocellular carcinoma

BACKGROUND & AIMS

Hepatocellular carcinoma (HCC) is highly malignant and prone to recur after surgical treatment. Differentiation between a true relapse of HCC and a second primary tumor is of clinical importance. However, no convenient method is currently available.

METHODS

Comparative genomic hybridization (CGH) was used to analyze 31 pairs of initial and recurrent HCC samples obtained from patients undergoing 2 consecutive surgeries. The resulting chromosomal aberration profiles were used as genomic fingerprints to determine tumor clonalities and their relationships.

RESULTS

Eleven recurrent tumors with high clonal relationship (CR) values (>0.95) were found to be relapsed HCCs, and 11 tumors with CR values close to 0 were found to be second primary HCCs. The other 9 paired samples had inconclusive CR values between 0.95 and 0.4. Two were confirmed by hepatitis B virus integration and X chromosome inactivation analysis to be de novo cancers (CR values, 0.35 and 0. 23, respectively). Initial HCCs that subsequently relapsed accumulated more chromosomal aberration events than those that developed de novo HCC (mean, 16.1 +/- 4.5 vs. 5.4 +/- 4.8 events; P < 0.01). Also, they more frequently showed gains on chromosome arms 3q, 6p, 8q, and 17q and losses on 4q and 16p.

CONCLUSIONS

CGH is useful for chromosomal aberration study and tumor clonality analysis. More and characteristic genomic changes in the initial HCC suggest that subsequent tumor recurrence is a true relapse.

The antiplatelet activity of tetramethylpyrazine is mediated through activation of NO synthase

Tetramethylpyrazine (TMPZ) is an active ingredient of a Chinese herbal medicine (Ligusticum wallichii Franchat). In this study, TMPZ (50-200 microM) significantly increased production of nitrate and cyclic GMP in human platelets within a 15-min incubation period. TMPZ concentration-dependently inhibited intracellular Ca2+ mobilization in human platelets stimulated by collagen (5 microg/ml). Furthermore, TMPZ concentration (50 and 200 microM)- and time (15 and 30 min)-dependently triggered endothelial-type constitutive nitric oxide synthase (ecNOS) protein expression in human platelets. These results indicated that TMPZ at micromolar concentrations stimulated nitric oxide production in human platelets via a novel mechanism that activated ecNOS protein expression.

Airway obstruction caused by a congenital epiglottic cyst

Congenital epiglottic cyst is a rare affliction with potential for airway obstruction. A newborn boy was referred to our department for evaluation of respiratory distress and inspiratory stridor 7 h after birth. Through a transnasal fiberoptic laryngoscopy examination, a diagnosis of an obstructive upper laryngeal cyst was made. Immediate endoscopic surgery was performed 20 h after birth to completely remove the lesion. Two days after surgery, the patient resumed normal breathing pattern and showed no further episodes of stridor or airway obstruction.

Assembly of a functional beta interferon enhanceosome is dependent on ATF-2-c-jun heterodimer orientation

Heterodimeric transcription factors, including the basic region-leucine zipper (bZIP) protein ATF-2-c-jun, are well-characterized components of an enhanceosome that mediates virus induction of the human beta interferon (IFN-beta) gene. Here we report that within the IFN-beta enhanceosome the ATF-2-c-jun heterodimer binds in a specific orientation, which is required for assembly of a complex between ATF-2-c-jun and interferon regulatory factor 3 (IRF-3). We demonstrate that correct orientation of the ATF-2-c-jun binding site is required for virus induction of the IFN-beta gene and for IRF-3-dependent activation of a composite ATF-2- c-jun-IRF site in the IFN-beta promoter. We also show that in vitro the DNA-bound ATF-2-c-jun heterodimer adopts a fixed orientation upon the binding of IRF-3 at an adjacent site in the IFN-beta enhancer and that the DNA-binding domain of IRF-3 is sufficient to mediate this effect. In addition, we show that the DNA-binding domain of ATF-2 is necessary and sufficient for selective protein-protein interactions with IRF-3. Strikingly, in vivo chromatin immunoprecipitation experiments with IFN-beta reporter constructs reveal that recruitment of IRF-3 to the IFN-beta promoter upon virus infection is dependent on the orientation of the ATF-2-c-jun heterodimer binding site. These observations demonstrate functional and physical cooperativity between the bZIP and IRF transcription factor families and illustrate the critical role of heterodimeric transcription factors in formation of the IFN-beta enhanceosome.