Synergistic cranberry juice combinations with natural-borne antimicrobials for the eradication of uropathogenic Escherichia coli biofilm within a short time

Urinary tract infections (UTI), one of the most common diseases in humans, are caused primarily by uropathogenic Escherichia coli (UPEC). Cranberry juice (CB) is a widely known prophylaxis for UTI, but the treatment of CB alone could not effectively eradicate preformed UPEC biofilms. The aim of this study was to develop enforced CB composites within a short time by adding a small quantity of natural borne antimicrobials. UPEC biofilms (initial: 6·0 log CFU per cm² ), formed on silicone coupons in artificial urine medium, were exposed to CB (4-8%), caprylic acid (CAR; 0·025-0·05%) and thymol (TM; 0·025-0·05%) at 37°C for 1 min. Individual treatment of each compound did not show the significant antibacterial effect on UPEC biofilms (P > 0·05). Otherwise, the survivor counts of biofilms were synergistically reduced with CB containing any of the antimicrobials. For example combined treatment with CB (8%) + CAR (0·05%) + TM (0·05%) resulted in a 6 log reduction in UPEC populations in the biofilm (no detectable bacteria remained) with 4·6 log of synergistic bactericidal effect. The confocal laser scanning microscope images indicated that any composites including TM might result in biofilm detachment from the surface. The present method is cost-effective and more acceptable to consumers as it is based on the synergistic interaction of natural borne antimicrobials. The results of this study could be widely applicable in the functional food, medical and healthcare field. SIGNIFICANCE AND IMPACT OF THE STUDY: Anti-biofilm effect of cranberry juice (CB) has been focused mainly on inhibiting biofilm formation of uropathogenic Escherichia coli (UPEC); however, combined treatment with natural borne antimicrobials derived from coconut oil (caprylic acid) and oregano essential oil (thymol) could synergistically enhance its eradicating activity against biofilms. This study developed novel CB composites showing marked anti-biofilm effects (complete eradication of UPEC biofilms within just 1 min).

Concomitant ALK translocation and EGFR mutation in lung cancer: a comparison of direct sequencing and sensitive assays and the impact on responsiveness to tyrosine kinase inhibitor

BACKGROUND

Epidermal growth factor receptor (EGFR) mutation and anaplastic lymphoma kinase (ALK) translocation are considered mutually exclusive in nonsmall-cell lung cancer (NSCLC). However, sporadic cases having concomitant EGFR and ALK alterations have been reported. The present study aimed to assess the prevalence of NSCLCs with concomitant EGFR and ALK alterations using mutation detection methods with different sensitivity and to propose an effective diagnostic and therapeutic strategy.

PATIENTS AND METHODS

A total of 1458 cases of lung cancer were screened for EGFR and ALK alterations by direct sequencing and flourescence in situ hybridization (FISH), respectively. For the 91 patients identified as having an ALK translocation, peptide nucleic acid (PNA)-clamping real-time PCR, targeted next-generation sequencing (NGS), and mutant-enriched NGS assays were carried out to detect EGFR mutation.

RESULTS

EGFR mutations and ALK translocations were observed in 42.4% (612/1445) and 6.3% (91/1445) of NSCLCs by direct sequencing and FISH, respectively. Concomitant EGFR and ALK alterations were detected in four cases, which accounted for 4.4% (4/91) of ALK-translocated NSCLCs. Additional analyses for EGFR using PNA real-time PCR and ultra-deep sequencing by NGS, mutant-enriched NGS increased the detection rate of concomitant EGFR and ALK alterations to 8.8% (8/91), 12.1% (11/91), and 15.4% (14/91) of ALK-translocated NSCLCs, respectively. Of the 14 patients, 3 who were treated with gefitinib showed poor response to gefitinib with stable disease in one and progressive disease in two patients. However, eight patients who received ALK inhibitor (crizotinib or ceritinib) showed good response, with response rate of 87.5% (7/8 with partial response) and durable progression-free survival.

CONCLUSIONS

A portion of NSCLC patients have concomitant EGFR and ALK alterations and the frequency of co-alteration detection increases when sensitive detection methods for EGFR mutation are applied. ALK inhibitors appear to be effective for patients with co-alterations.

A Fas-associated via death domain promoter polymorphism (rs10898853, -16C/T) as a risk factor for papillary thyroid cancer

PURPOSE

To determine whether a Fas-associated via death domain (FADD) promoter single-nucleotide polymorphism (SNP) is associated with susceptibility to papillary thyroid cancer (PTC) and clinicopathological features of PTC.

METHODS

To identify a possible association with PTC, 94 patients with PTC and 346 healthy controls were recruited. One promoter SNP (rs10898853, -16C/T) was analyzed by direct sequencing. Multiple logistic regression models (co-dominant, dominant, recessive, and log-additive models) were applied, and odds ratios (ORs), 95% confidence intervals (CIs), and p values were calculated.

RESULTS

The genotype of the promoter SNP (rs10898853) of FADD was found to be significantly associated with PTC in the co-dominant model 2 (T/T vs. C/C; p = 0.002, OR = 2.80, 95% CI = 1.39-5.65), the recessive model (p = 0.003, OR = 2.21, 95% CI = 1.31-3.71), and the log-additive model (p = 0.002, OR = 1.71, 95% CI = 1.20-2.44). Allele frequency analysis showed that the C allele of rs10898853 was significantly associated with an increased risk of PTC (p = 0.002, OR = 1.67, 95% CI = 1.21-2.32).

CONCLUSIONS

Our results suggest that the FADD promoter polymorphism is associated with susceptibility to PTC.

Proteins involved in DNA damage response pathways and survival of stage I non-small-cell lung cancer patients

BACKGROUND

Biological complexity leads to significant variation in the survival of patients with stage I non-small-cell lung cancer (NSCLC). DNA damage response (DDR) pathways play a critical role in maintaining genomic stability and in the progression of NSCLC. Therefore, the development of a prognostic biomarker focusing on DDR pathways is an intriguing issue.

PATIENTS AND METHODS

Expression of several proteins (ATM, ATMpS1981, γH2AX, 53BP1, 53BP1pS25, Chk2, Chk2pT68, MDC1, MDC1pS964, BRCA1pS1423, and ERCC1) and overall survival were investigated in 889 pathological stage I NSCLC patients.

RESULTS

Low expression of BRCA1pS1423 or ERCC1 was significantly associated with worse survival in the whole cohort of patients. Analysis performed based on histology revealed that low expression of γH2AX, Chk2pT68, or ERCC1 was a poor prognostic factor in squamous cell carcinoma patients [adjusted hazard ratio (aHR), Cox P: 1.544, 0.012 for γH2AX; 1.624, 0.010 for Chk2pT68; 1.569, 0.011 for ERCC1]. The analysis of the interaction between two proteins showed that this effect was more pronounced in squamous cell carcinoma patients. However, these effects were not detected in adenocarcinoma patients.

CONCLUSIONS

The proteins involved in DDR pathways exhibited differential expression between squamous cell carcinoma and adenocarcinoma and were important determinants of survival in stage I squamous cell carcinoma patients.

Tankyrase-1 function at telomeres and during mitosis is regulated by Polo-like kinase-1-mediated phosphorylation

Telomere length is critical for chromosome stability that affects cell proliferation and survival. Telomere elongation by telomerase is inhibited by the telomeric protein, TRF1. Tankyrase-1 (TNKS1) poly(ADP-ribosyl)ates TRF1 and releases TRF1 from telomeres, thereby allowing access of telomerase to the telomeres. TNKS1-mediated poly(ADP-ribosyl)ation also appears to be crucial for regulating the mitotic cell cycle. In searching for proteins that interact with polo-like kinase-1 (Plk1) by using complex proteomics, we identified TNKS1 as a novel Plk1-binding protein. Here, we report that Plk1 forms a complex with TNKS1 in vitro and in vivo, and phosphorylates TNKS1. Phosphorylation of TNKS1 by Plk1 appears to increase TNKS1 stability and telomeric poly(ADP-ribose) polymerase (PARP) activity. By contrast, targeted inhibition of Plk1 or mutation of phosphorylation sites decreased the stability and PARP activity of TNKS1, leading to distort mitotic spindle-pole assembly and telomeric ends. Taken together, our results provide evidence of a novel molecular mechanism in which phosphorylation of TNKS1 by Plk1 may help regulate mitotic spindle assembly and promote telomeric chromatin maintenance.

The effect and optimal dose of sufentanil in reducing injection pain of microemulsion propofol

Background

Propofol is used as an induction and maintenance agent for general anesthesia but it can cause adverse reactions like hyperlipidemia, growth of microorganisms, and pulmonary embolisms. Microemulsion propofol was developed to avoid these side effects but incidence and severity of pain on injection is higher than with lipid emulsion propofol. We aimed to compare the effects of sufentanil in analgesic doses for reducing the injection pain of microemulsion propofol.

Methods

The candidates included eighty patients, 19-60 years old and ASA I-II. They were randomly classified into four groups and pretreated with normal saline, sufentanil 0.1 µg/kg, 0.2 µg/kg or 0.3 µg/kg before injection of microemulsion propofol. Five minutes after receiving pretreatment drug, 2 mg/kg of microemulsion propofol was injected and VAS was recorded.

Results

There were no significant differences in the incidence of injection pain among the groups. Severity of injection pain was significantly lower in the sufentanil 0.3 µg/kg group than normal saline and sufentanil 0.1 µg/kg group. Significant differences in blood pressure and heart rate were observed in sufentanil groups only after endotracheal intubation. One patient each in sufentanil 0.1 µg/kg and 0.3 µg/kg group experienced mild cough, one from sufentanil 0.3 µg/kg group experienced dizziness and another showed signs of hypoxia. One patient each in normal saline and sufentanil 0.1 µg/kg group showed clinical symptoms of phlebitis in the injection area.

Conclusions

Pretreatment with sufentanil 0.3 µg/kg reduced the severity of microemulsion propofol injection pain without increasing arterial blood pressure and heart rate after endotracheal intubation.

Multiple psoas abscess formation after pharmacopuncture -a case report-

Acupuncture has been widely used in alternative medicine for pain relief but may have many complications due to lack of appropriate cares. Pharmacopuncture is a sort of acupuncture that injects a herbal ingredient through a thin tube for the purpose of combining the effects of the herb and acupuncture and it has many pitfalls. The agents used in pharmacopuncture are not refined for a desired effect and not produced by sterile standard processes under strict medical surveillance. We report a case of a 44-yr-old male patient who had multiple abscesses in the psoas region with fever, right low back and hip pain that began after the pharmacopuncture treatment. This case shows that although pharmacopuncture has been practiced widely, it is important that the appropriate aseptic technique should be used to prevent severe infections and other complications.

Birch's Law: Why Is It So Good?

Birch's law arises in the physics of solids as a linear approximation, in a certain range of density, of a power law. For a change of chemical composition within the same crystal structure, the velocity-density relation is constant with a slope of nearly -0.5 in the first-order approximation.

Natural killer T cells are dispensable in the development of allergen-induced airway hyperresponsiveness, inflammation and remodelling in a mouse model of chronic asthma

Natural killer T (NK T) cells have been shown to play an essential role in the development of allergen-induced airway hyperresponsiveness (AHR) and/or airway inflammation in mouse models of acute asthma. Recently, NK T cells have been reported to be required for the development of AHR in a virus induced chronic asthma model. We investigated whether NK T cells were required for the development of allergen-induced AHR, airway inflammation and airway remodelling in a mouse model of chronic asthma. CD1d-/- mice that lack NK T cells were used for the experiments. In the chronic model, AHR, eosinophilic inflammation, remodelling characteristics including mucus metaplasia, subepithelial fibrosis and increased mass of the airway smooth muscle, T helper type 2 (Th2) immune response and immunoglobulin (Ig)E production were equally increased in both CD1d-/- mice and wild-type mice. However, in the acute model, AHR, eosinophilic inflammation, Th2 immune response and IgE production were significantly decreased in the CD1d-/- mice compared to wild-type. CD1d-dependent NK T cells may not be required for the development of allergen-induced AHR, eosinophilic airway inflammation and airway remodelling in chronic asthma model, although they play a role in the development of AHR and eosinophilic inflammation in acute asthma model.

Decreased phosphorylation of STAT-1, STAT-4 and cytokine release in MDR-TB patients with primary resistance

SETTING

We recently showed that treatment failure rate was higher among multidrug-resistant tuberculosis (MDR-TB) patients without a previous history of tuberculosis (TB) treatment, or so-called 'primary resistance'.

OBJECTIVE

To investigate the phosphorylation levels of signal transducers and activators of transcription-1 (STAT-1) and STAT-4 and the subsequent cytokine release as a possible cause of a poor prognosis in MDR-TB patients with primary resistance.

DESIGN

Ten patients with successfully treated pulmonary TB without resistance, 12 MDR-TB patients with acquired resistance and 10 MDR-TB patients with primary resistance were enrolled. After 24 h stimulation of peripheral blood mononuclear cells (PBMC) with interferon-gamma (IFN-gamma), interleukin-12 (IL-12), purified protein derivative (PPD), or lysate of Mycobacterium tuberculosis, flow cytometric analysis of intracellular pSTAT-1 and pSTAT-4 were performed and secretion of IFN-gamma, IL-12p40 and tumour necrosis factor-alpha (TNF-alpha) was measured in culture supernatant.

RESULTS

The mean fluorescent intensities of pSTAT-1 and pSTAT-4 in PBMC of MDR-TB patients with primary resistance decreased on stimulation of IFN-gamma, PPD or lysate of M. tuberculosis when compared with patients with acquired resistance. In addition, secretion of IFN-gamma, IL-12p40 and TNF-alpha in these patients decreased on various stimuli.

CONCLUSION

Decreased phosphorylation of STAT-1, STAT-4, and of subsequent cytokine release, might be associated with a poor prognosis in MDR-TB patients with primary resistance.

High tumour islet macrophage infiltration correlates with improved patient survival but not with EGFR mutations, gene copy number or protein expression in resected non-small cell lung cancer

The purpose of this study was to investigate the prognostic value of tumour-associated macrophages with a focus on micro-anatomical localisation and determine whether molecular changes of the epidermal growth factor receptor (EGFR) are related to macrophage infiltration in resected non-small cell lung cancer (NSCLC). One hundred and forty-four patients were included in this study. Immunohistochemistry was used to identify CD68+ macrophages in the tumour islet and surrounding stroma. Epidermal growth factor receptor mutations were studied by direct sequencing. The EGFR gene copy number and protein expression were analysed by fluorescence in situ hybridisation and immunohistochemistry. Patients with a high tumour islet macrophage density survived longer than did the patient with a low tumour islet macrophage density (5-year overall survival rate was 63.9 vs 38.9%, P=0.0002). A multivariate Cox proportional hazard analysis revealed that the tumour islet macrophage count was an independent prognostic factor for survival (hazard ratio 0.471, 95% confidence interval 0.300-0.740). However, EGFR mutations, gene copy number, and protein expression were not related to the macrophage infiltration. In conclusion, tumour islet macrophage infiltration was identified as a strong favourable independent prognostic marker for survival but not correlated with the molecular changes of the EGFR in patients with resected NSCLC.

Interstitial lung disease in patients with polymyositis, dermatomyositis and amyopathic dermatomyositis

OBJECTIVE

To assess the prevalence, characteristics and prognostic factors of interstitial lung disease (ILD) in Korean patients with polymyositis (PM), dermatomyositis (DM) and amyopathic dermatomyositis (ADM).

METHODS

We reviewed the medical records of 72 consecutive PM and DM patients, including six patients with ADM, who were seen at the Rheumatology Clinic of Seoul National University Hospital between 1984 and 2003.

RESULTS

Twenty-nine PM/DM patients (40.3%) developed ILD. Anti-Jo-1 antibody and arthralgia were associated with the presence of ILD (P = 0.022 and P = 0.041, respectively), whereas dysphagia was more frequently found in patients without ILD (P = 0.041). Lung biopsies revealed diffuse alveolar damage (DAD) (n = 2), usual interstitial pneumonia (UIP) with DAD (n = 2), UIP (n = 1), and non-specific interstitial pneumonia (n = 2). Of the 29 patients, 11 (37.9%) died. The mean survival time in ILD patients was significantly shorter than in those without ILD (13.8+/-1.8 vs 19.2+/-0.9 yr, P = 0.017). Poor survival in ILD patients was associated with a Hamman-Rich-like presentation (P = 0.0000), ADM features (P = 0.0001) and an initial forced vital capacity (FVC) < or =60% (P = 0.024).

CONCLUSIONS

ILD was observed in 40.3% of Korean PM/DM patients and was associated with poor survival. A Hamman-Rich-like presentation, ADM features and an initial FVC < or =60% were associated with poor survival in ILD.

Autologous cardiomyocyte transplantation in an ovine myocardial infarction model

BACKGROUND

To evaluate the possibility of autologous cardiomyocyte transplantation, we transplanted cultured autologous cells into an infarct region developed by coronary artery ligation in an ovine model.

MATERIALS AND METHODS

A chronic heart failure model with a considerable portion of myocardial infarction was created in sheep using sequential ligation of the homonymous artery and its diagonal branch. Autologous cardiomyocytes were cultured and isolated from the right ventricular infundibulum. After a predetermined interval (one animal for two months and the other for three months), the two animals were reanesthetized and a suspension of cultured autologous vetricular cells in 0.3 ml of culture medium (1.2 x 10(7) cells) was injected into the center of three out of the four sites in the infarcted area using a tuberculin syringe. The same amount of culture medium was injected with an identical procedure into the center of the remaining site, as control. The animals were kept alive for a further month, and then sacrificed for postmortem heart examinations. Light microscopic analysis and immunohistochemical study for myoglobin were done.

RESULTS AND CONCLUSIONS

On postmortem gross examination, well-demarcated thin-walled anteroseptal infarcts with chamber enlargement were clearly seen in specimens from the two animals. Microscopic analysis showed homogenous fibrosis throughout the infarcted areas. In both animals, one of the three sites of cardiomycyte injection showed an islet of cardiomyocytes in the mid-myocardium, while none were observed in the control site of either animal. A layer of cardiomyocytes was observed in subendocardial regions, as it was in the control areas. In conclusion, cardiomyocyte transplantation into the infarct regions developed by coronary artery ligation in an ovine model was achieved with only limited success. An understanding of why only 33% of cardiomyocyte-injection sites demonstrated viable cardiomyocytes, in the form of tiny cell islets, remains to be elucidated.

Local expression and distribution of a storage protein in the ovary of Hyphantria cunea

Storage protein-1 (HcSP-1) is a major storage protein found in the hemolymph and fat body of Hyphantria cunea. HcSP-1 has a high methionine (6.0%) and low aromatic amino acid content (8.5%) (Cheon et al., 1998). In this study, the accumulation and expression of HcSP-1 in ovary was investigated using biochemical and immunocytochemical methods. HcSP-1 was detected in the ovaries in 6-day-old pupae and accumulated toward the end of pupal life, when HcSP-1 transcripts were detectable by Northern blot analysis and RT-PCR. In situ hybridization showed that the HcSP-1 mRNA was located in the nurse cells and follicular epithelial cells, but not in the oocyte. Though most of the HcSP-1 that is incorporated in the yolk bodies of the oocyte is probably sequestered from the surrounding hemolymph, HcSP-1 is an important yolk protein contributing to early yolk body formation before the development of patency by the follicular epithelium.

Effect of eccentric load cycling on microleakage of Class V flowable and packable composite resin restorations

Class V composite restorations are subject to the stresses that induce non-carious cervical lesions. This study evaluated the effect of eccentric oblique load on microleakage of restorations. Class V cavities were randomly prepared on the buccal surfaces of 40 recently extracted premolars and restored with composite resin according to manufacturers' directions. Teeth were randomly assigned to one of four treatment groups with 10 teeth per group: (1) flowable resin (Revolution) without load cycling; (2) packable resin (Prodigy Condensable) without load cycling; (3) flowable resin with load cycling (200,000 cycles) and (4) packable resin with load cycling (200,000 cycles). All teeth were then immersed in 2% methylene blue solution for 24 hours after thermocycling (500 cycles). Dye penetration was measured (scores 0-3). The results indicated that adding load cycling significantly increased microleakage (p < 0.05). No significant differences in microleakage were observed for flowable resin vs packable resin. Gingival margins had significantly more microleakage (p < 0.05) than occlusal margins.

LMP1-induced downregulation of CD99 molecules in Hodgkin and Reed-Sternberg cells

Hodgkin's and Reed-Sternberg (H-RS) cells are morphological hallmarks of Hodgkin's disease (HD). So far, several characteristics frequently seen in H-RS cells from different origins have been described, such as the high expression of Epstein-Barr virus latent membrane protein 1 (LMP1), the elevation of NF-kappaB activity, and the aberrant expression of molecules such as CD15, CD30, and CD99. Despite extensive studies on the nature of H-RS cells, the molecular mechanism by which H-RS cells are generated remained elusive. Recently, the forced down-regulation of CD99 was reported to induce typical H-RS phenotypes in vitro in a B cell line. Furthermore, it was revealed that LMP1 markedly reduces the CD99 expression at the transcriptional level. Since the presence of LMP1 is known to be associated with the H-RS cell formation, the data provide a possibility of linkage between LMP1 and HD via CD99, thus suggesting that, at least in part, the loss of CD99 may play a critical role in the pathogenic sequence to the formation of H-RS cells in HD. In this review, the role of CD99 in the generation of H-RS cells and its molecular mechanism will be suggested.

Butyrate sensitizes human colon cancer cells to TRAIL-mediated apoptosis

BACKGROUND

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a novel member of the tumor necrosis factor family, induces apoptosis in TRAIL-sensitive tumors through the activation of the caspase pathway. Sodium butyrate (NaBT) induces differentiation and apoptosis in certain colorectal cancers; the molecular mechanisms for these effects have not been clearly defined. The purpose of our study was to determine whether NaBT sensitizes TRAIL-resistant human colon cancer cells to the effects of TRAIL.

METHODS

Human colon cancer cells (KM12C, KML4A, and KM20) that are resistant to TRAIL treatment alone were treated with TRAIL (100 ng/mL), NaBT (5 mmol/L), or a combination of these agents and harvested for total RNA and protein. Western blots were performed to assess intracellular expression of Flice-like inhibitory protein (FLIP), a caspase inhibitor. Percent-specific apoptosis, relative caspase-3 activity, and Annexin-V immunofluorescence were determined at 24 and 48 hours. Cell cycle--related gene expression was assessed by RNase protection.

RESULTS

Treatment with NaBT for 24 and 48 hours decreased FLIP protein expression in all cell lines. Furthermore, NaBT sensitized these resistant cancer cells to the effects of TRAIL with significant increases noted in cell death, caspase-3 activity, and Annexin-V staining compared with NaBT alone.

CONCLUSIONS

Our findings suggest that the reduction of FLIP protein levels by NaBT renders TRAIL-resistant human colon cancer cells sensitive to TRAIL-mediated apoptosis. The combination of TRAIL with agents (such as NaBT, which target proteins that prevent cell death) may provide a more effective and less toxic regimen for the treatment of resistant colon cancers.

Competitive inhibition in vivo and skewing of the T cell repertoire of antigen-specific CTL priming by an anti-peptide-MHC monoclonal antibody

We have recently described a mAb, KP15, directed against the MHC-I/peptide molecular complex consisting of H-2D(d) and a decamer peptide corresponding to residues 311-320 of the HIV IIIB envelope glycoprotein gp160. When administered at the time of primary immunization with a vaccinia virus vector encoding gp160, the mAb blocks the subsequent appearance of CD8(+) CTL with specificity for the immunodominant Ag, P18-I10, presented by H-2D(d). This inhibition is specific for this particular peptide Ag; another H-2D(d)-restricted gp160 encoded epitope from a different HIV strain is not affected, and an H-2L(d)-restricted epitope encoded by the viral vector is also not affected. Using functional assays and specific immunofluorescent staining with multivalent, labeled H-2D(d)/P18-I10 complexes (tetramers), we have enumerated the effects of blocking of priming on the subsequent appearance, avidity, and TCR Vbeta usage of Ag-specific CTL. Ab blocking skews the proportion of high avidity cells emerging from immunization. Surprisingly, Vbeta7-bearing Ag-specific TCR are predominantly inhibited, while TCR of several other families studied are not affected. The ability of a specific MHC/peptide mAb to inhibit and divert the CD8(+) T cell response holds implications for vaccine design and approaches to modulate the immune response in autoimmunity.

Molecular mechanisms contributing to necrotizing enterocolitis

OBJECTIVE

To examine the cellular mechanisms involved in the pathogenesis of necrotizing enterocolitis (NEC).

SUMMARY BACKGROUND DATA

Necrotizing enterocolitis is a major cause of death and complications in neonates; the cellular mechanisms responsible for NEC are unknown. The inducible form of cyclooxygenase (i.e., COX-2) is activated by the transcription factor nuclear factor (NF)-kappaB and is thought to play a role in inflammation.

METHODS

Segments of perforated and adjacent uninvolved small intestine from neonates with NEC were analyzed for COX-2 expression by immunohistochemistry. NEC was induced in weanling (18 days old) rats by occlusion of superior mesenteric vessels for 1 hour and intraluminal injection of platelet activating factor (50 micro/kg). Small intestine was harvested for protein extraction. Western immunoblot was performed to determine expression of COX-2. Gel shift assays were performed to assess NF-kappaB binding activity.

RESULTS

Immunohistochemical analysis showed increased COX-2 protein expression in the perforated intestinal sections of all 36 neonates but not in adjacent normal intestine. Increased expression of COX-2 protein and NF-kappaB binding activity was noted in the small intestine of weanling rats at 0 and 3 hours after induction of NEC.

CONCLUSIONS

Increased COX-2 expression was identified in all neonatal intestinal segments resected for perforated NEC. In addition, a coordinate induction of COX-2 expression and NF-kappaB binding was noted in a rodent model of NEC. These findings suggest that the COX-2/NF-kappaB pathway may play a role in the pathogenesis of NEC. Therapeutic agents that target this pathway may prove useful in the treatment or possible prevention of NEC.

cDNA sequence and gene expression of storage protein-2--a juvenile hormone-suppressible hexamerin from the fall webworm, Hyphantria cunea Drury

We isolated and sequenced a cDNA clone corresponding to storage protein-2 (SP-2) from the fall webworm, Hyphantria cunea. The cDNA for SP-2 (2572 bp) codes for a 747-residue protein with a predicted molecular mass of 88.5 kDa. The calculated isoelectric point is 7.6. Multiple alignment analysis of amino acid sequence revealed that SP-2 is most similar to BJHSP2 (74.3% identity). According to both the phylogenetic analyses and criteria for amino acid composition, SP-2 belongs to the subfamily of moderately methionine-rich storage proteins (3.2% methionine, 11.8% aromatic amino acid). Topical application of the JH analog, methoprene, after head ligation of larvae, suppressed transcription of the SP-2 gene, indicating hormonal effects at the transcriptional level. The SP-2 transcript was detected by Northern blot analysis in Malpighian tubules, in addition to the fat body where it was most abundant. The local expression of SP-2 in Malpighian tubules suggests that it may have some function in that organ.

Special phase matching of second-harmonic generation in helical ferroelectric liquid crystal cells

The helical structures in ferroelectric liquid crystals can be utilized to realize a special phase matching for second-harmonic generation (SHG) when two counter fundamental waves propagate along the helical axis and the wavelength of SHG is near the photonic (selective reflection) band edge. On the basis of the exact theory [Drevensek-Olenik and Copic, Phys. Rev. E 56, 581 (1997)], a simple analytical description is derived and some characteristic features of the special phase matching are shown. (1) Special phase matching is definitely achieved under particular combinations of polarization. (2) The SH spectrum is related to a subsidiary oscillating structure in the selective reflection spectrum. The maximum SH intensity is realized at the first dip of the oscillation near one of the edges in the selective reflection band. (3) The thickness (d) dependence of the maximum SH intensity is d4 in thick cells, while it is d2 for conventional phase matching. (4) The linewidth for the SH peak is d(-3) dependent, which is much narrower than in conventional phase matching.

Incidence and characterization of Listeria spp. from foods available in Korea

A total of 410 domestic Korean food samples were analyzed for the presence of Listeria spp. by the conventional U.S. Department of Agriculture protocol, and presumptive strains were identified by morphological, cultural and biochemical tests according to Bergey's manual and confirmed by API-Listeria kit. Among the total 410 food samples, 46 samples (11.2%) were found to be contaminated with Listeria species. Among the 46 strains of Listeria spp. isolates, 8 strains (17.42%) for Listeria monocytogenes, 3 strains (6.5%) for Listeria seeligeri, 33 strains (71.7%) for Listeria innocua, and 2 strains (4.4%) for Listeria welshimeri were identified, respectively. Also, only beef, chicken, pork, frozen foods, and sausage were contaminated with L. monocytogenes, and the other products were free of L. monocytogenes. Of 46 Listeria spp. isolates, L. innocua (71.7%) was the most predominantly isolated in a variety of foods compared to other Listeria spp. An in vitro virulence assay for Listeria spp. using myeloma and hybridoma cells from murine and human sources was performed. The result showed that only L. monocytogenes killed approximately 95 to 100% hybridoma cells after 6 h and the other Listeria species, such as L. innocua, L. seeligeri, and L. welshimeri strains had about 0 to 10% lethal effect on hybridoma cells. Also, an antibiotic susceptibility test showed that Listeria spp. isolates were very susceptible to the antibiotics tested, except for nalidixic acid. Also, serotyping results showed 75% of L. monocytogenes isolates from beef, chicken, and frozen pizza belonged to serotype 1 and 25% from sausage were type 4.

Positional change of the hyoid bone after bilateral sagittal split osteotomy with rigid and wire fixation

The purpose of this study was to compare positional changes of the hyoid bone and the amount of postsurgical compensation in mandibular position in patients who received either wire or rigid fixation after surgery. Data were analyzed from 97 patients (25 males and 72 females) who were randomized to receive wire (43) or rigid (54) fixation after mandibular advancement surgery as part of a multicenter clinical trial. Radiographs were digitized before surgery (T2), immediately after surgery (T3), and 8 weeks (T4), 6 months (T5), 1 year (T6), and 2 years (T7) after surgery. The wire group had greater sagittal relapse of the hyoid bone at T6 (P =.007), which persisted at T7 (P =.02). Both groups showed upward movement of the hyoid bone after surgery. There was no relationship between the vertical change in the the hyoid bone position and the vertical position of mandible (B point y coordinate, mandibular plane). However, there was a relationship between the horizontal hyoid bone position and B point during the postsurgical period (rigid, r = 0.450; wire, r = 0.517). The direct distance from the hyoid bone to basion increased (P <.001) in both groups at T3 and then recovered its original length after 8 weeks (P <.001). The rigid group showed no significant change in distance from the hyoid to the genial tubercles, but the wire group showed recovery of the muscle length at T6 (P <.05) and T7 (P <.05).

CD99 regulates the transport of MHC class I molecules from the Golgi complex to the cell surface

The down-regulation of surface expression of MHC class I molecules has recently been reported in the CD99-deficient lymphoblastoid B cell line displaying the characteristics of Hodgkin's and Reed-Sternberg phenotype. Here, we demonstrate that the reduction of MHC class I molecules on the cell surface is primarily due to a defect in the transport from the Golgi complex to the plasma membrane. Loss of CD99 did not affect the steady-state expression levels of mRNA and protein of MHC class I molecules. In addition, the assembly of MHC class I molecules and the transport from the endoplasmic reticulum to the cis-Golgi occurred normally in the CD99-deficient cells, and no difference was detected between the CD99-deficient and the control cells in the pattern and degree of endocytosis. Instead, the CD99-deficient cells displayed the delayed transport of newly synthesized MHC class I molecules to the plasma membrane, thus causing accumulation of the molecules within the cells. The accumulated MHC class I molecules in the CD99-deficient cells were colocalized with alpha-mannosidase II and gamma-adaptin in the Golgi compartment. These results suggest that CD99 may be associated with the post-Golgi trafficking machinery by regulating the transport to the plasma membrane rather than the endocytosis of surface MHC class I molecules, providing a novel mechanism of MHC class I down-regulation for immune escape.

Mapping the ligand of the NK inhibitory receptor Ly49A on living cells

We have used a recombinant, biotinylated form of the mouse NK cell inhibitory receptor, Ly49A, to visualize the expression of MHC class I (MHC-I) ligands on living lymphoid cells. A panel of murine strains, including MHC congenic lines, was examined. We detected binding of Ly49A to cells expressing H-2D(d), H-2D(k), and H-2D(p) but not to those expressing other MHC molecules. Cells of the MHC-recombinant strain B10.PL (H-2(u)) not only bound Ly49A but also inhibited cytolysis by Ly49A(+) effector cells, consistent with the correlation of in vitro binding and NK cell function. Binding of Ly49A to H-2D(d)-bearing cells of different lymphoid tissues was proportional to the level of H-2D(d) expression and was not related to the lineage of the cells examined. These binding results, interpreted in the context of amino acid sequence comparisons and the recently determined three-dimensional structure of the Ly49A/H-2D(d) complex, suggest a role for amino acid residues at the amino-terminal end of the alpha1 helix of the MHC-I molecule for Ly49A interaction. This view is supported by a marked decrease in affinity of an H-2D(d) mutant, I52 M, for Ly49A. Thus, allelic variation of MHC-I molecules controls measurable affinity for the NK inhibitory receptor Ly49A and explains differences in functional recognition in different mouse strains.

Antibodies directed against the MHC-I molecule H-2Dd complexed with an antigenic peptide: similarities to a T cell receptor with the same specificity

alphabeta TCRs, which use an Ab-like structure to form a combining site, recognize molecular complexes consisting of peptides bound to MHC class I (MHC-I) or class II (MHC-II) molecules. To explore the similarities and differences between Ab and T cell recognition of similar structures, we have isolated two mAbs, KP14 and KP15, that specifically bind H-2D(d) complexed with an HIV envelope gp160-derived peptide, P18-I10. These Abs are MHC and peptide specific. Fine specificity of mAb binding was analyzed using a panel of synthetic peptides, revealing similarities between the mAb and a cloned TCR with the same specificity. These two mAbs used the same V(H) and J(H) gene segments, but different D, Vkappa, and Jkappa genes. Administered in vivo, mAb KP15 blocked the induction of CTL specific for recombinant vaccinia virus-encoded gp160, indicating its ability to bind endogenously generated MHC/peptide complexes. Analysis of the fine specificity of these mAbs in the context of their encoded amino acid sequences and the known three-dimensional structure of the H-2D(d)/P18-I10 complex suggests that they bind in an orientation similar to that of the TCR. Thus, the plasticity of the B cell receptor repertoire and the structural similarities among BCR and TCR allow Abs to effectively mimic alphabeta TCRs. Such mAbs may be useful in the therapeutic modulation of immune responses against infectious agents or harmful self Ags as well as in tracing steps in Ag processing.

A novel point mutation of the splicing donor site in the intron 2 of the plasmin inhibitor gene

Plasmin inhibitor (PI) is a major physiological inhibitor of plasmin-mediated fibrinolysis; hence, its deficiency results in a severe haemorrhagic diathesis. We analyzed the PI gene of a French boy apparently homozygous for PI deficiency and his heterozygous parents. Both alleles of the homozygous patient had a novel G to A transition at the consensus splicing donor site in the intron 2 of the PI gene. In an expression assay using the heterologous cells transfected with the mutant PI expression vector, 3 types of aberrant transcripts using a cryptic splicing donor site within the intron 2 were detected. All of these mRNAs had a stop codon upstream of the cryptic splicing site and encode only 25 amino acids, comprising the first 21 amino acids of the signal peptide (27 amino acids) plus 4 new amino acids. This mutant was designated as PI-Paris-Trousseau.

Segmenting skin lesions with partial-differential-equations-based image processing algorithms

In this paper, a partial-differential equations (PDE)-based system for detecting the boundary of skin lesions in digital clinical skin images is presented. The image is first preprocessed via contrast-enhancement and anisotropic diffusion. If the lesion is covered by hairs, a PDE-based continuous morphological filter that removes them is used as an additional preprocessing step. Following these steps, the skin lesion is segmented either by the geodesic active contours model or the geodesic edge tracing approach. These techniques are based on computing, again via PDEs, a geodesic curve in a space defined by the image content. Examples showing the performance of the algorithm are given.

Prevention of mucosal atrophy: role of glutamine and caspases in apoptosis in intestinal epithelial cells

Glutamine starvation induces apoptosis in enterocytes; therefore glutamine is important in the maintenance of gut mucosal homeostasis. However, the molecular mechanisms are unknown. The caspase family of proteases constitutes the molecular machinery that drives apoptosis. Caspases are selectively activated in a stimulus-specific and tissue-specific fashion. The aims of this study were to (1) identify specific caspases activated by glutamine starvation and (2) determine whether a general caspase inhibitor blocks glutamine starvation-induced apoptosis in intestinal epithelial cells. Rat intestinal epithelial (RIE-1) cells were deprived of glutamine. Specific caspase activation was measured using fluorogenic substrate assay. Apoptosis was quantified by DNA fragmentation and Hoechst nuclear staining. Glutamine starvation of RIE-1 cells resulted in the time-dependent activation of caspases 3 (10 hours) and 2 (18 hours), and the induction of DNA fragmentation (12 hours). Caspases 1 and 8 remained inactive ZVAD-fluoromethyl ketone, a general caspase inhibitor, completely blocked glutamine starvation-induced caspase activation, DNA fragmentation, and nuclear condensation. These results indicate that glutamine starvation selectively activates specific caspases, which leads to the induction of apoptosis in RIE-1 cells. Furthermore, inhibition of caspase activity blocked the induction of apoptosis, suggesting that caspases are potential molecular targets to attenuate apoptotic responses in the gut.

Mannose trimming targets mutant alpha(2)-plasmin inhibitor for degradation by the proteasome

We have previously characterized the molecular and cellular mechanisms of alpha(2)-plasmin inhibitor (alpha(2)PI) deficiency. The mutant alpha(2)PI-Nara and alpha(2)PI-Okinawa proteins were found to be retained and degraded in cells stably expressing these mutant forms of alpha(2)PI. Degradation of the two mutant alpha(2)PI proteins, mediated by proteasomes, occurred after a lag time of 1.5 h during which glucose trimming took place. The mutant alpha(2)PI proteins were not ubiquitinated. Inhibition of mannosidase activity blocked the degradation of the mutant alpha(2)PI proteins without resulting in any changes in their binding to calnexin. Inhibition of glucose removal completely blocked the interaction between the alpha(2)PI proteins and the molecular chaperone calnexin. Under these conditions, mannose residues were removed from the oligosaccharides even when glucose residues were not processed. With mannose removal, the glucose-untrimmed mutant forms of alpha(2)PI, which failed to bind to calnexin, were degraded by proteasomes. The initiation of mannose trimming was a prerequisite for their degradation. Our findings show that modification of oligosaccharides of the mutant forms of alpha(2)PI determines their recognition by the degradation apparatus and that mannose trimming is important for targeting the mutant alpha(2)PI proteins for the degradation pathway.

Three cases of pancreas allograft dysfunction

We present dincopathologic features of three cases of biopsy-proven pancreas allograft dysfunction in Korea. All patients had advanced insulin-dependent diabetes mellitus (IDDM). Case 1 was a 30-year-old woman who underwent a simultaneous pancreas-kidney transplantation. Urinary infection developed 6 days after the operation, which remitted and reappeared, when urine amylase level was normal. Since the 55th day after the operation, intermittent hematuria has persisted. Cytomegalovirus inclusions were detected on the urinary bladder and grafted duodenal mucosa. The graft was removed due to perforation of the grafted duodenum and panperitonitis. Case 2 was a 27-year-old man undergoing pancreas transplantation alone (PTA). Ten days after the transplatation, the level of 24 urine amylase decreased and the graft was not delineated by 99mTc DTPA scintigraphy. Allograft needle biopsy revealed multiple acinar cell necrosis and mild lymphocytic infiltration which were compatible with mild acute rejection. Case 3 was a 25-year-old man undergoing cadevaric PTA. Three months after the transplantation, graft was removed due to gastric perforation associated with cytomegalovirus and angiodestructive fungal infection. Various causes of pancreas allograft dysfunction can be diagnosed by needle biopsy, thus appropriate biopsy specimen should be taken using improved biopsy technique.

Development of new adherent mutant from human myeloma-derived cell line: in vitro model of anaplastic transformation of myeloma

Anaplastic myeloma is a rare but distinct, biologically aggressive variant of myeloma which usually results from dedifferentiation or anaplastic transformation of the myeloma cells. The molecular mechanisms that determine the biologic behavior of anaplastic myeloma and effective treatment modalities have not been well known due to lack of in vitro models. In the present study, we have developed an anaplastically transformed mutant from a human myeloma-derived cell line. In the process of long-term culture of the myeloma-derived IM-9 cell line in low serum and nutrient conditions, an adherent mutant line was developed and named IM-9/AD. This mutant cell line displayed several characteristics resembling anaplastic myeloma such as: 1, large cells with large vesicular nucleus and prominent nucleolus, multinuclearity and high mitotic figures; 2, loss of leukocyte-associated antigens; and 3, higher tumorigenecity in scid mice than its parental cell line. This newly developed mutant cell line may serve as a readily available in vitro model to investigate the biology of anaplastic myeloma.

NK and CTL recognition of a single chain H-2Dd molecule: distinct sites of H-2Dd interact with NK and TCR

We generated transgenic mice expressing a single-chain beta2-microglobulin (beta2m)-H-2Dd. The cell-surface beta2m-H-2Dd molecule was expressed on a beta2m-deficient background and reacted with appropriate mAbs. It was of the expected m.w. and directed the normal development of CD8+ T cells in the thymus of a broad TCR repertoire. It also presented both exogenously provided and endogenous peptide Ags to effector CD8+ T cells. In tests of NK cell education and function, it failed to reveal any interaction with NK cells, suggesting that the site of the interaction of NK receptors with H-2Dd was disrupted. Thus, the sites of TCR and NK receptor interaction with H-2Dd are distinct, an observation consistent with independent modes of TCR and NK receptor evolution and function.

Thrombomodulin with the Asp468Tyr mutation is expressed on the cell surface with normal cofactor activity for protein C activation

Thrombomodulin (TM) is an endothelial cell glycoprotein that acts as an anticoagulant. Mutation in the TM gene is a potential risk factor for thrombosis. The first TM mutation identified was a heterozygous substitution of T for G at nucleotide position 1456, which predicted Asp468 with Tyr in a Ser/Thr-rich domain. To evaluate the reported TM gene mutation as a possible cause of thrombosis, we transiently tranfected a vector for TM gene carrying the mutation to mammalian COS7 cells. TM antigen levels in lysates of cells transfected with variant TM were comparable to those in preparations of normal TM. The TM cofactor activity for protein C (PC) activation on the variant TM-expressing cells was similar to that of the control. The Michaelis constant Km and Vmax. of variant TM for PC activation were shown to be similar compared to those of normal TM. The affinity of each TM for thrombin in PC activation was also similar. We obtained several stable cell lines expressing normal and variant TM. Lysate of the cell lines with normal and variant TM genes had a similar expression level of TM antigen. Pulse-chase analysis showed that normal and variant TM were glycosylated and resistant to endoglycosidase H, indicating that the variant TM was expressed on the cell surface in a mature form. Variant TM protein is apparently expressed on the cell surface with normal cofactor activity for PC activation. It is unlikely that the TM variant directly causes thrombosis by mechanism of reduced expression or impaired cofactor activity for PC activation, which comprises a major anticoagulant activity of TM.

Inflammatory pseudotumor of carotid artery: a case report

Inflammatory pseudotumor is an uncommon round and spindle cell proliferative lesion of unknown etiology that occurs most commonly in the lung. But it also occurs in diverse extrapulmonary locations such as the abdomen, retroperitoneum, pelvis, heart, head and neck, upper respiratory tract, trunk, bladder and extremities. The extrapulmonary inflammatory pseudotumor is often larger, less well circumscribed and multinodular. Proximity of the tumor to vital structures or involvement of vital organs compromises the opportunity for complete resection, thus higher recurrence rates are often reported even after surgical treatment. The authors report a case of inflammatory pseudotumor originating from the common carotid artery in a 42-year-old female patient with a rapidly growing neck mass, treated by en-bloc resection of inflammatory pseudotumor and a long segment of common carotid artery followed by PTFE graft interposition.

Clonal analysis of a solitary follicular nodule of the thyroid with the polymerase chain reaction method

Solitary follicular nodules of the thyroid occasionally create a diagnostic problem, especially in the differential diagnosis between adenoma and nodular hyperplasia To obtain confident histologic parameters of clonal lesions, we analyzed DNA samples prepared from paraffin-embedded archival tissue from 20 solitary follicular nodules of the thyroid for clonality with the polymerase chain reaction (PCR) method. On the base of X chromosome inactivation mosaicism, we tested restriction fragment-length polymorphism of the phosphoglycerate kinase (PGK) gene and a highly polymorphic short tandem repeat of the human androgen receptor (HUMARA) gene. Of 18 informative cases, 10 were monoclonal, 7 were polyclonal, and 1 showed microsatellite instability. All of the five completely encapsulated nodules were monoclonal. Four of the five unencapsulated nodules showed polyclonality. Of the seven partially encapsulated nodules, four were monoclonal, and the others were polyclonal. The former showed 50% or more of encapsulation degree, whereas the latter showed less than 50%. The capsule tended to be thicker in monoclonal nodules (mean, 0.33 mm) than in polyclonal nodules (mean, 0.13 mm). Other histologic features of the nodules and surrounding parenchymal changes had no significance with respect to predicting clonality. This study suggests that the degree of encapsulation and capsular thickness are morphologically important for predicting the clonality of the thyroid nodule.

Effect of implant number on transverse bending moments during simulated unilateral loading of mandibular fixed-detachable prostheses

High bending moments acting on osseointegrated implants due to transverse forces are believed to be potential contributors to mechanical implant failure. Theoretically, the rigidity of a system comprised of five implants would seem to counter these moments more effectively than one with only three implants. To study this, we built an experimental model comprised of five Brånemark implants embedded in an acrylic mandibular edentulous arch and connected by a metal framework. This lower prosthesis was mounted with an opposing maxillary complete denture in nonbalanced lingualized occlusion on a semiadjustable articulator. Eccentric static bites were simulated by fixing the dentures at 1.5 mm left and right working side (WS) and balancing side (BS) positions, respectively, and loading the upper member of the articulator with 50 N. The distal right implant abutment was transformed into a loadcell by bonding four strain gauges at 90 degrees intervals across its surface. Three 10-second static load ramps were carried out for each of 4 experiments: (1) WS loadcell with five implants, (2) BS loadcell with five implants, (3) WS loadcell with three implants, and (4) BS loadcell with three implants. Transverse bending moments were found to be significantly higher on the WS for the three-implant prosthesis as compared to the five-implant design (1.469 Ncm for five implants vs 2.151 Ncm for three implants; p = 0.001, Student's t-test). This difference was insignificant on the BS (0.532 Ncm for five implants vs 0.521 Ncm for three implants; p = 0.34). These results suggest that a higher number of mandibular implants may decrease the bending moments affecting mandibular fixed-detachable prostheses during unilateral biting tasks.

Engagement of CD99 induces apoptosis through a calcineurin-independent pathway in Ewing's sarcoma cells

Programmed cell death (PCD) is a prominent feature of the development of the immune and nervous systems. In both systems, widespread PCD occurs in primitive progenitor cells during development. In this study, we demonstrated that Ewing's sarcoma (ES) cells, undifferentiated neural precursors, underwent apoptosis upon engagement of CD99 with anti-CD99 monoclonal antibody. Apoptosis via CD99 occurred only in the undifferentiated state of ES cells, but not in differentiated ES cells. CD99-induced apoptosis in ES cells appeared to require de novo synthesis of RNA and protein as well as caspase activation. Cyclosporin A, known to be a potent inhibitor of both calcineurin activation and mitochondrial permeability transition pore opening, inhibited CD99-mediated apoptosis, whereas FK-506, a specific calcineurin inhibitor, did not, indicating the induction of CD99-mediated apoptosis through a calcineurin-independent pathway. Furthermore, the dying cells displayed the reduction of mitochondrial transmembrane potential (delta psi m). These results suggest that CD99 engagement induce CsA-inhibitable mitochondrial permeability transition pore opening, followed by a reduction of delta psi m and caspase activation, thereby leading to apoptosis. Based on these results, we suggest the possible involvement of CD99 in the apoptotic processes that occur during nervous system development and also its application in immunotherapeutic trials for ES cases.

Generation of cells with Hodgkin's and Reed-Sternberg phenotype through downregulation of CD99 (Mic2)

Despite the fact that Hodgkin's and Reed-Sternberg (H-RS) cells are morphological hallmarks of Hodgkin's disease (HD), the nature of H-RS cells still remains to be resolved. Here we report that downregulation of CD99 (Mic2) leads to the generation of cells with an H-RS phenotype. IM9 and BJAB B-cell lines that were transfected with an antisense CD99 expression construct showed the morphological and immunological characteristics of H-RS cells such as multinuclearity, expression of CD15, decreased expression of major histocompatibility complex (MHC) class I and CD45RB, and deregulated secretion of cytokines. The reduced expression of CD99 was also confirmed in H-RS cells of patient's lymph nodes and three HD-derived cell lines, L428, KM-H2, and HDLM-2. Moreover, features characteristic of H-RS cells were completely abolished by forced expression of CD99 and by a constitutively active form of Rac, which functions downstream of CD99. We suggest that CD99 molecules play a crucial role in regulating functions and morphology of cells through a Rac-Rho signaling pathway and that the loss of CD99 expression is a significant molecular event to generate H-RS cells.

Fundoplication and gastrostomy

Fundoplication and gastrostomy are among the most frequently performed procedures in infants and children. A laparoscopic approach with decreased morbidity has made fundoplication (with or without gastrostomy) more acceptable for patients who have significant gastroesophageal reflux disorders. Diagnostic evaluations to determine the presence of pathological gastroesophageal reflux have remained the same for patients being considered for open or laparoscopic procedures. Gastrostomy alone also is performed for patients who have swallowing difficulties or failure to thrive, after excluding the presence of gastroesophageal reflux. The authors review the indications and techniques of laparoscopic fundoplication and gastrostomy, as well as their experience with 390 patients.

A cell surface molecule, JL1; a specific target for diagnosis and treatment of leukemias

We previously reported a novel differentiation antigen, which is specifically expressed in stage II double positive (CD4+CD8+) human cortical thymocytes (Park et al, J Exp Med 1993; 178: 1447-1451). This study was designed to investigate the expression pattern of JL1 in various types of leukemic cells from patients and normal hematopoietic cells to evaluate the possibility as a tool for diagnosis and treatment of leukemia. The expression of JL1 antigen was observed in 75.6% of leukemic cases (117 out of 154 leukemic patients tested) on flow cytometric analysis. The percentage of JL1-positive cases of T lineage acute lymphoblastic leukemia (T-ALL) (92.6%) was higher than that of other types of leukemias (75%). The presence of JL1 antigen was also confirmed by immunoblotting and immunoprecipitation. Since the JL1 antigen is selectively expressed on the surface of human leukemic cells but not on the mature human peripheral blood cells, normal bone marrow cells and various types of normal tissues, JL1 could be an excellent candidate for an immunodiagnostic and immunotherapeutic tool for hematopoietic malignancies such as leukemia.

ILK (beta1-integrin-linked protein kinase): a novel immunohistochemical marker for Ewing's sarcoma and primitive neuroectodermal tumour

ILK (beta1-integrin-linked protein kinase) is a recently identified 59-kDa serine/threonine protein kinase that interacts with the cytoplasmic domain of the beta1-integrin containing four ankyrin-like repeats. We have developed a polyclonal antibody against ILK and explored the ILK immunoreactivity in normal human cells and tissues. ILK was mainly expressed in cardiac muscle and skeletal muscles. Surprisingly, ILK expression was observed in Ewing's sarcoma (ES; 100%), primitive neuroectodermal tumour (PNET; 100%), medulloblastoma (100%), and neuroblastoma (33.3%), whereas other small round cell sarcomas were not stained by the anti-ILK antibody. These results suggest that ILK could be a novel marker for tumours with primitive neural differentiation. Our findings support the notion that ES is a tumour that is closely related to PNET and that both originate from the neuroectoderm. ILK may be a sensitive and specific immunohistochemical marker and useful for the positive identification of ES and PNET in formalin-fixed, paraffin-embedded tissue sections.

Development of a new anti-CD4 monoclonal antibody (YG23) which inhibits the formation of colonies of human bone marrow progenitor cells

We have previously reported CD4 expression in CD34+ hematopoietic progenitor cells and suggested a role of CD4 in normal hematopoiesis and its possible relationship with the pathogenesis of acquired immunodeficiency syndrome (AIDS). To investigate whether CD4 expression in bone marrow progenitor cells can explain bone marrow suppression in AIDS, monoclonal antibodies (mAbs) against human CD4 were developed by immunizing Balb/c mice with human thymocytes. Three mAbs completely blocked the binding of Leu3a antibody, a well-known anti-CD4 mAb, to thymocytes, which indicates overlap between the epitopes recognized by these and Leu3a antibodies. Interestingly, one of these mAbs, YG23, significantly inhibited colony formation of human bone marrow progenitor cells treated with GM-CSF. This is the first demonstration that ligation of CD4 by an anti-CD4 mAb suppresses GM-CSF mediated proliferation and differentiation of human hematopoietic progenitor cells by modifying the intracellular signaling pathway through CD4 molecules. Based on these findings, we propose that alteration of CD4 signaling by either cross-linked gp120 or antibodies directed against a certain epitope shared with the YG23 binding site of the CD4 molecule may play a role in bone marrow dysfunction in AIDS patients.

Butyrate attenuates BCLX(L) expression in human fibroblasts and acts in synergy with ionizing radiation to induce apoptosis

Ionizing radiation is a poor inducer of apoptosis in many cell types. In this study we investigated what effect the differentiation agent butyrate had on the cellular levels of the apoptosis regulators BCL2, BCLX(L) and BAX and on radiation-induced apoptosis. It was found that butyrate significantly lowered the level of the apoptosis antagonist BCLX(L) in a time- and dose-dependent manner in diploid human fibroblasts. The reduction of the level of BCLX(L) protein by butyrate correlated with an increased induction of apoptosis in cells irradiated with ionizing radiation. Butyrate also acted in synergy with ultraviolet (UV) light and cisplatin to induce apoptosis in human fibroblasts. Radiosensitization was obtained when butyrate was added before and/or after irradiation, although the combination of treatment both before and after irradiation was the most effective. Our results suggest that butyrate acts in synergy with ionizing radiation, UV light and cisplatin to induce apoptosis, perhaps by lowering the level of the apoptosis antagonist BCLX(L) in cells.

Central venous catheter access

Central venous access for the purpose of supplying parenteral nutrition to the pediatric age group requires a careful definition of the patient's caloric need, estimated duration of therapy, and an assessment of available sites. Peripheral vein parenteral nutrition is limited by caloric density of the nutrient fluids, while peripherally inserted central catheters (PICC) offers a new technology for accessing central veins while obviating the risk of central vein access. Routes of central vein access are several and there are also a variety of catheters available for placement. Tunneled percutaneous placement of silicone rubber cuffed catheters via the subclavian vein approach is that technique we use most commonly. The risks of such access catheters include mechanical risks of placement, venous thrombosis of the access sites, and most importantly catheter related infections, either at the exit site, the subcutaneous tunnel or pouch, or even generalized sepsis. With a full knowledge of the spectrum of access techniques, access materials, and risks, safe total parenteral nutrition can be safely delivered to the children in need.

CD99 (MIC2) regulates the LFA-1/ICAM-1-mediated adhesion of lymphocytes, and its gene encodes both positive and negative regulators of cellular adhesion

Despite the fact that integrin-mediated lymphocyte adhesion is a crucial event for an appropriate immune response, little is known about the mechanisms that control the adhesion and deadhesion processes generated by the engagement of CD99 between various types of immune cells. Here we report that the CD99 gene encodes two distinct proteins with opposite functions in the LFA-1/intercellular adhesion molecule 1 (ICAM-1)-mediated cell adhesion process. The two forms of the CD99 protein are produced by alternative splicing of the CD99 gene transcript. The major form induced homotypic adhesion of the human B lymphoblastoid cell line IM-9, whereas the minor, truncated form inhibited the adhesion process. Activation of the major form of CD99 with anti-CD99 monoclonal antibodies induced rapid aggregation of IM-9 cells, which was blocked by the addition of mAbs to LFA-1 or intracellular adhesion molecule 1. Overexpression of the minor truncated form of CD99 markedly down-regulated the expression of LFA-1. The two forms of CD99 are differentially expressed in most human cells tested and are highly conserved in monkey. Taken together, these observations suggest that the two forms of CD99 function in vivo in both positive and negative regulation of LFA-1-mediated adhesion of lymphocytes during an immune response.

CD99 (MIC2) regulates the LFA-1/ICAM-1-mediated adhesion of lymphocytes, and its gene encodes both positive and negative regulators of cellular adhesion

Despite the fact that integrin-mediated lymphocyte adhesion is a crucial event for an appropriate immune response, little is known about the mechanisms that control the adhesion and deadhesion processes generated by the engagement of CD99 between various types of immune cells. Here we report that the CD99 gene encodes two distinct proteins with opposite functions in the LFA-1/intercellular adhesion molecule 1 (ICAM-1)-mediated cell adhesion process. The two forms of the CD99 protein are produced by alternative splicing of the CD99 gene transcript. The major form induced homotypic adhesion of the human B lymphoblastoid cell line IM-9, whereas the minor, truncated form inhibited the adhesion process. Activation of the major form of CD99 with anti-CD99 monoclonal antibodies induced rapid aggregation of IM-9 cells, which was blocked by the addition of mAbs to LFA-1 or intracellular adhesion molecule 1. Overexpression of the minor truncated form of CD99 markedly down-regulated the expression of LFA-1. The two forms of CD99 are differentially expressed in most human cells tested and are highly conserved in monkey. Taken together, these observations suggest that the two forms of CD99 function in vivo in both positive and negative regulation of LFA-1-mediated adhesion of lymphocytes during an immune response.