Electric Cell-Substrate Impedance Sensing (ECIS) as a Platform for Evaluating Barrier-Function Susceptibility and Damage from Pulmonary Atelectrauma

Biophysical insults that either reduce barrier function (COVID-19, smoke inhalation, aspiration, and inflammation) or increase mechanical stress (surfactant dysfunction) make the lung more susceptible to atelectrauma. We investigate the susceptibility and time-dependent disruption of barrier function associated with pulmonary atelectrauma of epithelial cells that occurs in acute respiratory distress syndrome (ARDS) and ventilator-induced lung injury (VILI). This in vitro study was performed using Electric Cell-substrate Impedance Sensing (ECIS) as a noninvasive evaluating technique for repetitive stress stimulus/response on monolayers of the human lung epithelial cell line NCI-H441. Atelectrauma was mimicked through recruitment/derecruitment (RD) of a semi-infinite air bubble to the fluid-occluded micro-channel. We show that a confluent monolayer with a high level of barrier function is nearly impervious to atelectrauma for hundreds of RD events. Nevertheless, barrier function is eventually diminished, and after a critical number of RD insults, the monolayer disintegrates exponentially. Confluent layers with lower initial barrier function are less resilient. These results indicate that the first line of defense from atelectrauma resides with intercellular binding. After disruption, the epithelial layer community protection is diminished and atelectrauma ensues. ECIS may provide a platform for identifying damaging stimuli, ventilation scenarios, or pharmaceuticals that can reduce susceptibility or enhance barrier-function recovery.

Flow characteristics of urethral catheters of the same caliber vary between manufacturers

BACKGROUND

Clean intermittent catheterization (CIC) is frequently prescribed for bladder dysfunction, either per urethra or via a continent catheterizable channel. Small catheters may be required for infants or continent channels. Success with CIC is highly dependent upon patient and family compliance. The urinary flow rate through the catheter is an important factor, which can decrease CIC time and improve quality of life. There is little objective information regarding flow rate through urinary catheters to guide catheter recommendation or prescription. Clinically, we noted that there was a difference in flow among catheter brands, and we questioned if catheters of the same-labeled diameter exhibit the same flow characteristics, which could have implications for catheter selection.

METHODS

Twenty-one commercially available male pediatric urinary catheters from nine brands were tested (11 straight tip, 10 coude tip). Nine of the 21 tested catheters had a hydrophilic coating. All tested catheters shared a 10F outer diameter. For each, microscopic imaging and a precision caliper were used to measure the inner diameter and tip inlet area. A hydraulic system modified from ASTM standard testing specifications was used to simulate bladder catheterization. Measurement of each catheter was repeated five times using three different static hydraulic pressures (20, 40 and 50 cmH₂O). Catheter flow rate and structural measurements were identified and the fastest and slowest of the catheters are presented in the table. The variable flow rates between brands were due to the differences in catheter structural characteristics such as the inner diameter (ID) and the tip inlet area to inner lumen area ratio (AR). The maximum variation of flow rate of all tested 10F catheters was 48%, ID varied up to 22%, from 1.71 to 2.11 mm or 5.13-6.33F. AR varied up to 166%. The table delineates the fastest and slowest rates at three measured pressures. The outer diameter labeled 10F on packaging was true to size.

CONCLUSIONS

Based on packaging information, providers, and patients are unable to predict urinary flow through a catheter and thus use information regarding flow rate to guide catheter selection. This information cannot be calculated based on ideal flow calculations and could be listed on packaging to assist physicians and families in selecting the optimal urinary catheter for CIC.

Microscale distribution and dynamic surface tension of pulmonary surfactant normalize the recruitment of asymmetric bifurcating airways

We investigate the influence of bifurcation geometry, asymmetry of daughter airways, surfactant distribution, and physicochemical properties on the uniformity of airway recruitment of asymmetric bifurcating airways. To do so, we developed microfluidic idealized in vitro models of bifurcating airways, through which we can independently evaluate the impact of carina location and daughter airway width and length. We explore the uniformity of recruitment and its relationship to the dynamic surface tension of the lining fluid and relate this behavior to the hydraulic (PHyd) and capillary (PCap) pressure drops. These studies demonstrate the extraordinary importance of PCap in stabilizing reopening, even in highly asymmetric systems. The dynamic surface tension of pulmonary surfactant is integral to this stability because it modulates PCap in a velocity-dependent manner. Furthermore, the surfactant distribution at the propagating interface can have a very large influence on recruitment stability by focusing surfactant preferentially to specific daughter airways. This implies that modification of the surfactant distribution through novel modes of ventilation could be useful in inducing uniformly recruited lungs, aiding in gas exchange, and reducing ventilator-induced lung injury.

NEW & NOTEWORTHY The dynamic surface tension of pulmonary surfactant is integral to the uniformity of asymmetric bifurcation airway recruitments because it modulates capillary pressure drop in a velocity-dependent manner. Also, the surfactant distribution at the propagating interface can have a very large influence on recruitment stability by focusing surfactant preferentially to specific daughter airways. This implies that modification of the surfactant distribution through novel modes of ventilation could be useful in inducing uniformly recruited lungs, reducing ventilator-induced lung injury.

Magnesium iodide-catalyzed synthesis of 2-substituted quinazolines using molecular oxygen and visible light

We disclose a novel and efficient synthesis of 2-substituted quinazolines by aerobic photooxidative reaction catalyzed by magnesium iodide.

Correlation of circulating betatrophin concentrations with insulin secretion capacity, evaluated by glucagon stimulation tests

AIM

To investigate the relationship between plasma betatrophin concentrations and insulin secretion capacity in people with Type 2 diabetes.

METHODS

Glucagon stimulation tests (1 mg) were performed in 70 people with Type 2 diabetes after an overnight fast. Plasma betatrophin concentrations were measured using an enzyme-linked immunosorbent assay. Insulin secretion capacity was evaluated by measuring increments of C-peptide concentration in response to glucagon stimulation, and creatinine clearance was determined by comparing creatinine concentrations in serum and 24-h urine samples.

RESULTS

Plasma betatrophin concentrations were positively correlated with duration of Type 2 diabetes (r = 0.34, P = 0.003), and negatively correlated with increments of C-peptide concentration (r = 0.37, P = 0.001) and creatinine clearance (r = 0.37, P = 0.001). The correlation with increments of C-peptide concentration remained significant after adjustment for age and duration of Type 2 diabetes (r = 0.25, P = 0.037). Multivariate analysis identified age and increments of C-peptide concentration as independent factors associated with plasma betatrophin levels.

CONCLUSION

Plasma betatrophin levels inversely correlate with insulin secretion capacity, suggesting that betatrophin levels are regulated by insulin secretion capacity in humans.

Aerobic photooxidative direct asymmetric aldol reactions of benzyl alcohols using water as the solvent

We report an aerobic photooxidative direct asymmetric aldol reaction using water as the solvent.

The unusual symmetric reopening effect induced by pulmonary surfactant

This study investigates the stability of a finger of air as it propagates into a liquid-filled model of a liquid-filled model of a pulmonary bifurcation. We seek to elucidate the stability characteristics of the reopening of daughter airways, an event that may be important to the treatment of acute lung disease. To do so, we investigated the symmetry of reopening under conditions of nearly constant surface tension with 1) purified H2O or 2) an anionic surfactant (sodium dodecyl sulfate). Dynamic surface tension was investigated using pulmonary surfactant (Infasurf) with and without the presence of albumin. Flow visualization was accomplished using a microparticle image velocimetry (μ-PIV)/shadowgraph system through which we measured 1) the propagation velocity of the finger of air that reopens each daughter branch, and 2) the instantaneous and averaged velocity field of liquid phase surrounding the tip of the propagating bubble. Only pulmonary surfactant demonstrated the ability of maintaining a nearly symmetric propagation in the daughter channels, which is likely to lead to homogeneous airway reopening. In contrast, when pulmonary surfactant was inactivated by albumin or when the system was held at a nearly constant surface tension, reopening occurred asymmetrically. Our analysis suggests that Infasurf's dynamic surface tension qualities are important to stabilize the removal of liquid obstructions. This demonstrates a new important function of pulmonary surfactant for airway reopening of a multibranched network.

Lagrangian transport properties of pulmonary interfacial flows

Disease states characterized by airway fluid occlusion and pulmonary surfactant insufficiency, such as respiratory distress syndrome, have a high mortality rate. Understanding the mechanics of airway reopening, particularly involving surfactant transport, may provide an avenue to increase patient survival via optimized mechanical ventilation waveforms. We model the occluded airway as a liquid-filled rigid tube with the fluid phase displaced by a finger of air that propagates with both mean and sinusoidal velocity components. Finite-time Lyapunov exponent (FTLE) fields are employed to analyse the convective transport characteristics, taking note of Lagrangian coherent structures (LCSs) and their effects on transport. The Lagrangian perspective of these techniques reveals flow characteristics that are not readily apparent by observing Eulerian measures. These analysis techniques are applied to surfactant-free velocity fields determined computationally, with the boundary element method, and measured experimentally with micro particle image velocimetry (μ-PIV). We find that the LCS divides the fluid into two regimes, one advected upstream (into the thin residual film) and the other downstream ahead of the advancing bubble. At higher oscillatory frequencies particles originating immediately inside the LCS experience long residence times at the air-liquid interface, which may be conducive to surfactant transport. At high frequencies a well-mixed attractor region is identified; this volume of fluid cyclically travels along the interface and into the bulk fluid. The Lagrangian analysis is applied to velocity data measured with 0.01 mg ml(-1) of the clinical pulmonary surfactant Infasurf in the bulk fluid, demonstrating flow field modifications with respect to the surfactant-free system that were not visible in the Eulerian frame.

A translating stage system for µ-PIV measurements surrounding the tip of a migrating semi-infinite bubble

We have designed, fabricated and evaluated a novel translating stage system (TSS) that augments a conventional micro particle image velocimetry (µ-PIV) system. The TSS has been used to enhance the ability to measure flow fields surrounding the tip of a migrating semi-infinite bubble in a glass capillary tube under both steady and pulsatile reopening conditions. With conventional µ-PIV systems, observations near the bubble tip are challenging because the forward progress of the bubble rapidly sweeps the air-liquid interface across the microscopic field of view. The translating stage mechanically cancels the mean bubble tip velocity, keeping the interface within the microscope field of view and providing a tenfold increase in data collection efficiency compared to fixed-stage techniques. This dramatic improvement allows nearly continuous observation of the flow field over long propagation distances. A large (136-frame) ensemble-averaged velocity field recorded with the TSS near the tip of a steadily migrating bubble is shown to compare well with fixed-stage results under identical flow conditions. Use of the TSS allows the ensemble-averaged measurement of pulsatile bubble propagation flow fields, which would be practically impossible using conventional fixed-stage techniques. We demonstrate our ability to analyze these time-dependent two-phase flows using the ensemble-averaged flow field at four points in the oscillatory cycle.

μ-PIV measurements of the ensemble flow fields surrounding a migrating semi-infinite bubble

Microscale particle image velocimetry (μ-PIV) measurements of ensemble flow fields surrounding a steadily-migrating semi-infinite bubble through the novel adaptation of a computer controlled linear motor flow control system. The system was programmed to generate a square wave velocity input in order to produce accurate constant bubble propagation repeatedly and effectively through a fused glass capillary tube. We present a novel technique for re-positioning of the coordinate axis to the bubble tip frame of reference in each instantaneous field through the analysis of the sudden change of standard deviation of centerline velocity profiles across the bubble interface. Ensemble averages were then computed in this bubble tip frame of reference. Combined fluid systems of water/air, glycerol/air, and glycerol/Si-oil were used to investigate flows comparable to computational simulations described in Smith and Gaver (2008) and to past experimental observations of interfacial shape. Fluorescent particle images were also analyzed to measure the residual film thickness trailing behind the bubble. The flow fields and film thickness agree very well with the computational simulations as well as existing experimental and analytical results. Particle accumulation and migration associated with the flow patterns near the bubble tip after long experimental durations are discussed as potential sources of error in the experimental method.

Ets-1 proto-oncogene as a potential predictor for poor prognosis of lung adenocarcinoma

The proto-oncogene Ets-1 is a transcription factor that is known to regulate certain matrix metalloproteinases and plasminogen activator, which have been associated with malignant behaviors in solid carcinomas. We hypothesized that Ets-1 expression is also associated with tumor progression and a worse prognosis in lung carcinoma patients. To clarify the role of the Ets-1 proto-oncogene, the expression of Ets-1 in non-small cell lung carcinomas using 156 paraffin-embedded specimens was determined in surgically resected tissue samples. Immunohistochemical staining showed Ets-1 expression in 82 cases of 156 carcinomas (53%): 36 of 52 (69%) squamous cell carcinomas, 41 of 96 (43%) adenocarcinomas, and 5 of 8 (63%) other carcinomas. In adenocarcinomas, a higher proportion of acinar type expressed Ets-1 compared to papillary or alveolar type (p < 0.05). The proportion of adenocarcinoma that expressed Ets-1 increased with poorer histologic differentiation of the adenocarcinoma (p < 0.05). Ets-1 positive adenocarcinomas had a larger mean size than Ets-1 negative adenocarcinomas (p < 0.01). In adenocarcinoma patients, expression of Ets-1 was associated with disease-free (p = 0.09) and overall survivals (p < 0.05) after lung resection. Such relationship was not observed among squamous cell carcinoma patients. Our findings indicate that Ets-1 expression is related to histopathological differentiation, morphogenesis, and tumor progression of lung adenocarcinomas. Ets-1 appears to be a useful predictor of poor prognosis after surgical resection in lung adenocarcinoma patients. Ets-1 expression could be used to evaluate the malignant behaviors of lung adenocarcinomas.

136 CLOSED SYSTEM OF GEL-LOADING-TIP VITRIFICATION FOR IN VITRO-PRODUCED BOVINE BLASTOCYSTS BEFORE AND AFTER BIOPSY

Ultra-rapid cooling by direct plunging of gel-loading-tip (GL-tip) into liquid nitrogen (LN2) contributed to the high post-warm survival rates of in-vitro-produced (IVP) bovine embryos (Tominaga and Hamada 2001 J. Reprod. Dev. 47, 267–273). Since GL-tip vitrification and other ultra-rapid vitrification methods have potential risk of microbiological contamination in the LN2, the current study was undertaken to develop a closed system of GL-tip vitrification for IVP bovine blastocysts before and after biopsy. Day 7 blastocysts were produced in vitro (Tominaga et al. 2000 Theriogenology 53, 1669–1680), and biopsied for sex determination (Tominaga and Hamada 2004 Theriogenology 61, 1181–1191). The blastocysts were exposed first to 10% ethylene glycol (EG) +10% DMSO in TCM-199/20% FCS for 2 min at 37°C, and then placed in vitrification medium with 20% EG + 20% DMSO + 0.6 M sucrose in TCM 199/20% FCS for 30 s at 37°C. Three to 4 blastocysts in 0.6 µL of the vitrification medium were aspirated into a GL-tip (NK-tip; Nippon Medical &amp; Chemical Instruments Co., Ltd., Osaka, Japan). Immediately before being plunged into LN2, the tip of the GL-tip was sealed by dipping into 100% glycerol at 4°C, and the opposite open end of the GL-tip was sealed by inserting a holding stick under LN2 vapor. After warming in 0.25 M sucrose solution at 37°C, the glycerol-seal was removed from the tip by gentle shaking. The blastocysts diluted in a two-step manner were cultured up to 72 h for survival assay. Within the 72 h of culture, intact embryos that initiated hatching and biopsied embryos that re-expanded were considered as surviving. Two more biopsied blastocysts derived from ovum pickup, IVF, and IVC were vitrified–warmed in the closed system, and then transferred to 2 recipients. The results indicate no significant difference in the post-thaw survival rates of either intact or biopsied blastocysts in both closed and open systems (Table 1). One recipient became pregnant and delivered a female calf. Gestation period (287 days) and birth weight (22 kg) were within the normal range of the Tajima strain of Japanese Black cattle. We reached the conclusion that the closed system of GL-tip vitrification was simple and highly effective for IVP bovine blastocysts before and after biopsy. Table 1. In vitro survival of intact and biopsied bovine blastocysts after GL-tip vitrification in closed and open systems

Role of macrophage migration inhibitory factor in ovalbumin-induced airway inflammation in rats

Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine that reportedly counteracts the anti-inflammatory effect of endogenous glucocorticoids. There have only been a few reports that demonstrate a potential link between MIF and bronchial asthma. In an attempt to further clarify the precise role of MIF in asthma, the present authors examined the effect of anti-MIF antibody (Ab) on airway inflammation and airway hyperresponsiveness in an ovalbumin-immunised rat asthma model. Actively immunised Brown Norway rats received ovalbumin inhalation with or without treatment of anti-MIF Ab. The levels of MIF in bronchoalveolar lavage fluid were significantly elevated after the ovalbumin challenge. An immunohistochemical study revealed positive immunostaining for MIF in bronchial epithelium, even in nonsensitised rats, and the MIF staining in bronchial epithelium was enhanced after the ovalbumin challenge. Anti-MIF Ab significantly decreased the number of total cells, neutrophils and eosinophils in the bronchoalveolar lavage fluid of the ovalbumin-challenged rats, and also attenuated the ovalbumin-induced airway hyperresponsiveness to ovalbumin and methacholine. However, anti-MIF Ab did not affect the level of serum ovalbumin-specific IgE, suggesting that anti-MIF Ab did not suppress immunisation itself. The results indicate that macrophage migration inhibitory factor plays a crucial role in airway inflammation and airway hyperresponsiveness in asthma.

Trace of native cattle in Japanese Holstein assessed by mitochondrial DNA sequence polymorphism

On the basis of sequence variation in the displacement loop region of mtDNA, 588 Japanese and North American Holstein cows were classified into 5 mitochondrial haplotypes, which were found in Japanese Black cattle. One of the haplotypes (named type 1), which was present at the highest frequency in Japanese Black cattle, was not observed in either European or African cattle. This haplotype is characterized by 2 single-nucleotide polymorphisms. One is called the type B polymorphism, and it refers to a base change from T to C at nucleotide 16042 of the mitochondrial genome (T160042C). The other is called the type I polymorphism, and it refers to the base change as G16093A. The proportion of the Japanese Holstein population with both polymorphisms was 18.3%, whereas none of the North American cows had this genotype. Because the mitochondrial types were inherited maternally, it is clear that a considerable number of Japanese Holstein cows are descended from native Japanese cattle. Polymorphisms B and I accounted for no variance in the estimated breeding value for milk production among cows from the Hyogo herd (582 cows) or the Chiba region herd (758 cows). This result suggests that most autosomal genes of native animals have been successively replaced by those of pure Holstein after grading up of over 15 generations, even though resulting animals have native animal-oriented mitochondrial types and may still have some number of the native autosomal genes.

Association between interleukin-18 gene polymorphism 105A/C and asthma

BACKGROUND

IL-18 has been shown to exert anti-allergic or allergy-promoting activities, but the existence of genetic polymorphisms in the coding regions of IL-18 gene has not been demonstrated.

OBJECTIVE

The aim of this study was to investigate whether polymorphism is present in the coding regions of the IL-18 gene and, if so, to further analyse the association between polymorphism and asthma in a case-control study.

METHODS

We screened the coding regions of the IL-18 gene for polymorphisms by using PCRsingle-stranded conformation polymorphism and direct sequencing of PCR products, followed by analysis of the association between polymorphism and asthma.

RESULTS

We identified one polymorphism (105A/C) in the coding regions. The frequency of the 105A allele was significantly higher in asthmatic patients than in controls (P<0.01; odds ratio (OR)=1.83 (1.37-2.26)). Significant linkage disequilibrium was observed between the 105A/C and -137G/C polymorphisms in the 5' flanking region of the IL-18 gene (D=0.58, P<0.0001). However, in asthmatic patients the 105A allele was not associated with either total serum IgE or IL-18 levels.

CONCLUSION

The 105A/C polymorphism of the IL-18 gene may be associated with the pathogenesis of asthma.

Increased levels of interleukin-8 in BAL fluid from smokers susceptible to pulmonary emphysema

BACKGROUND

It has previously been shown that smokers with computed tomographic (CT) evidence of subclinical emphysema have signs of neutrophil activation, despite having no appreciable increase in the number of neutrophils in their bronchoalveolar lavage (BAL) fluid.

METHODS

The levels of the following chemoattractants in BAL fluid from 61 community based older volunteers classified into four groups according to current smoking status and the presence or absence of emphysema were determined: interleukin 8 (IL-8), epithelial neutrophil activating protein 78 (ENA-78) and leukotriene B(4) (LTB(4)) which are primarily chemotactic for neutrophils; monocyte chemoattractant protein 1 (MCP-1) and macrophage inflammatory protein-1alpha (MIP-1alpha) which are predominantly chemotactic for mononuclear leucocytes.

RESULTS

Of the five chemoattractants studied, only the level of IL-8 in BAL fluid clearly distinguished between subjects with and without emphysema among current smokers (median values 34.7 and 12.2 pg/ml, respectively, p<0.01). In addition, the levels of IL-8 and neutrophil elastase-alpha(1) protease inhibitor complex in BAL fluid were significantly correlated (r=0.65, p<0.01). There was no difference in either the release of IL-8 from cultured alveolar macrophages at 24 hours or the expression of IL-8 messenger RNA of alveolar macrophages in the two groups of current smokers with and without emphysema.

CONCLUSION

An accelerated response of IL-8 to chronic smoking is a factor that characterises those smokers who are susceptible to pulmonary emphysema, although the cellular source of IL-8 remains to be determined.

Angiotensin-converting enzyme gene polymorphism in relation to HLA-DR in sarcoidosis

OBJECTIVES

To investigate if an insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme (ACE) gene associates with HLA-DR alleles previously found to be of prognostic interest in Scandinavian sarcoidosis patients. This may contribute to characteristics associated with these HLA-DR alleles, such as a good (DR17) or poor (DR14 or 15) prognosis. DESIGN, SETTINGS AND SUBJECTS: Polymerase chain reaction (PCR) was used for analysing an I/D polymorphism in the gene coding for ACE in 138 subjects; 65 controls and 73 sarcoidosis patients, and for HLA-DR genotyping 67 patients. Serum ACE level (S-ACE) was measured in all controls and 72 patients. Sixty-one patients were classified as chronic or nonchronic after 2 years follow-up. All patients were recruited and followed at our outpatient clinic.

RESULTS

No significant differences in ACE alleles or genotypes were seen between controls and patients or between patients positive and negative for DR17 or DR14/15. The ACE genotype did not differ between nonchronic and chronic patients. The ACE genotype tended to influence the S-ACE in patients, whilst in controls S-ACE significantly differed between the ACE genotypes.

CONCLUSION

This study does not support an association between ACE genotype and sarcoidosis or disease outcome. However, because significantly (P < 0.001) more DR17 positive (17 of 19) than DR14/15 positive (seven of 26) patients were classified as nonchronic, these results instead strengthen the prognostic importance of HLA-DR alleles in Scandinavian sarcoidosis patients.

(CCTTT)n repeat polymorphism in the NOS2 gene promoter is associated with atopy

BACKGROUND

Several studies have shown that nitric oxide (NO) plays a role in the regulation of the T(H)1/T(H)2 balance, indicating the potential for NO to contribute to the development of atopy and several other allergic diseases, including bronchial asthma. NO synthase 2 (NOS2) is critically involved in the synthesis of NO during several inflammatory states, and the gene encoding NOS2 is located at chromosome 17q11.2-q12, where 2 genome scans have identified a candidate locus for atopy and asthma.

OBJECTIVE

The 14-repeat allele of the (CCTTT)(n) repeat polymorphism in the NOS2 promoter region is a powerful enhancer of promoter activity in reporter constructs in vitro. We tested whether this potentially functional allele in the NOS2 gene influences the development of atopy and asthma.

METHODS

We studied a total of 497 unrelated Japanese subjects (141 nonatopic healthy controls, 102 atopic healthy controls, 56 nonatopic asthmatic subjects, and 198 atopic asthmatic subjects). The odds ratio (OR) was calculated for atopy and asthma in carriers of the 14-repeat allele through use of logistic regression models. Atopy was defined as a positive specific IgE level to at least 1 of 10 common inhaled allergens.

RESULTS

The 14-repeat allele was inversely associated with atopy (OR = 0.42, P < .01). The association remained significant when the model was controlled for asthmatic status (OR = 0.36, P < .01). This allele, however, was associated neither with the development of asthma nor with total serum IgE levels.

CONCLUSION

Our findings suggest that the (CCTTT)(n) repeat polymorphism in the promoter of the NOS2 gene that affects promoter activity is a risk factor for the development of atopy, and this genetic effect seems independent of asthma.

Measurement of serum hyaluronic acid level during the perioperative period of liver resection for evaluation of functional liver reserve

BACKGROUND AND AIM

The serum hyaluronic acid (HA) concentrations reflect the degree of hepatic fibrosis and sinusoidal endothelial cell damage. The HA concentrations were examined to evaluate liver damage during the perioperative period of hepatectomy.

METHODS

The HA level of serum samples from 79 patients who underwent a hepatectomy was measured, and the results were compared to conventional liver function tests, the degree of fibrosis, liver regeneration and complications.

RESULTS

Hyaluronic acid concentrations correlated with the severe fibrosis or histological activity index, and also correlated with liver function tests including transaminase level, platelet counts, prothrombin time activity, indocyanine green retention rate at 15 min (ICG R15), liver activity at 15 min by technetium-99m galactosyl human serum albumin scintigraphy (LHL 15), and portal pressure. The HA level postoperatively correlated with liver function, especially with total bilirubin. Hyaluronic acid levels at day 28 postoperatively correlated with ICG R15 and LHL 15. The hyaluronic acid level before surgery and at day 28 postoperatively correlated with the regeneration of remnant liver in major hepatectomy. The HA levels were significantly higher in patients with hepatic failure or prolonged ascites.

CONCLUSION

Our results indicate that the measurement of the HA level is useful for monitoring liver damage or predicting complications associated with liver surgery.

Prognostic factors in hepatic metastases of colorectal carcinoma: immunohistochemical analysis of tumor biological factors

The present study was designed to provide a systemic analysis of prognosis in 62 patients who underwent hepatic resection for colorectal liver metastasis. The analyzed factors included microvessel counts stained by CD34 and expression of two adhesion molecules, E-cadherin and CD44 variant exon 6-(v6) in these tumors. No significant factors related to recurrence were identified and only negative expression of CD44v6 tended to correlate with recurrence (P = 0.075). A short disease-free period to recurrence was noted in patients with high CEA levels (>10 ng/ml) and H2/3 classification. A short surgical margin, H2/3 classification, high microvessel counts (>60/field, x200), and negative expression of CD44v6 and E-cadherin tended to be associated with poor prognosis. A high microvessel count was the most significant prognostic factor by multivariate Cox proportional hazards regression model. Hepatic resection without tumor exposure and a careful follow-up in cases identified with poor prognostic factors are necessary.

Increased total serum IgE levels in patients with asthma and promoter polymorphisms at CTLA4 and FCER1B

BACKGROUND

Increasing evidence indicates that total serum IgE levels are largely determined by genetic factors, and we recently established that the -109C/T promoter polymorphism at FCER1B is a genetic factor that affects total serum IgE levels. The gene encoding cytotoxic T lymphocyte antigen 4 (CTLA4) is another candidate factor in high IgE responsiveness, because B7-CD28/CTLA4 interaction can promote the differentiation and development of the T(H)2 lymphocyte subset.

OBJECTIVE

We intended to determine whether CTLA4 is associated with increased levels of total serum IgE or with the development of asthma or atopy.

METHODS

We performed a case-control study involving 339 patients with asthma and 305 healthy control subjects, of whom 226 of the patients with asthma and 219 of the healthy control subjects had previously been genotyped for the -109C/T promoter polymorphism at FCER1B. In the current study, we genotyped 2 polymorphisms in the CTLA4 gene, one involving the promoter (-318C/T) and the other involving exon 1 (+49A/G), in addition to the FCER1B promoter polymorphism.

RESULTS

Patients with asthma who were homozygous for the -318C allele at the CTLA4 promoter region had higher levels of total serum IgE than patients with asthma carrying the -318T allele (P =.00470). The analysis of -318C/T (at CTLA4) and -109C/T (at FCER1B) promoter polymorphisms showed a significant correlation between the combined genotypes and increased levels of total IgE in patients with asthma (P =.000014). In contrast, no correlation between total serum IgE levels and -318C/T or +49A/G genotypes was detected in 305 healthy control subjects. There was no evidence indicating an association between a putative allele for asthma or atopy and alleles at any of the CTLA4 polymorphic loci.

CONCLUSION

Our findings suggest that promoter polymorphisms of both CTLA4 and FCER1B are genetic factors that influence total serum IgE levels in patients with asthma. This supports the theory that variance in total serum IgE levels in patients with asthma is determined by mutations in multiple genes, each of which has a relatively small effect on the phenotype.

Coexpression of inducible nitric oxide synthase and COX-2 in hepatocellular carcinoma and surrounding liver: possible involvement of COX-2 in the angiogenesis of hepatitis C virus-positive cases

Expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) has been reported to be responsible for enhanced tumor growth and angiogenesis in various tumors. However, the relationships between tumor vascularity and COX-2 and iNOS expression have not been evaluated in hepatocellular carcinoma (HCC). In this study, we examined the expression of iNOS and COX-2 and microvessel density (MVD) by immunohistochemical staining in 100 tissue sections collected from HCC patients. iNOS expression was significantly higher in hepatitis C virus (HCV)-positive HCCs (P = 0.011). COX-2 expression was significantly correlated with iNOS expression (P = 0.046) and tumor MVD (P = 0.011) in HCV-positive HCCS: iNOS expression was neither correlated with MVD nor had any influence on patient survival; however, combined negative expression of iNOS and COX-2 had a significant impact on patient survival (P = 0.041 and 0.018, log-rank test for overall and recurrence-free survival rate, respectively). The present findings suggest that combined expression of iNOS and COX-2 may play an important role in prognosis of HCV-positive HCC patients and that this could be partially attributable to modulation of angiogenesis by COX-2.

The gene polymorphism of tumor necrosis factor-beta, but not that of tumor necrosis factor-alpha, is associated with the prognosis of sarcoidosis

OBJECTIVES

Few genetic markers for the prognosis of sarcoidosis have been found. Tumor necrosis factor (TNF)-alpha has been implicated in the pathogenesis of sarcoidosis. Induced TNF-alpha or TNF-beta levels have been shown to be associated with the polymorphisms of the TNF genes. We investigated the roles of such polymorphisms in the development and prolongation of sarcoidosis.

SUBJECTS AND MEASUREMENTS

One hundred ten Japanese patients with sarcoidosis and 161 control subjects were genotyped for three biallelic polymorphisms in the promoter region of TNF-alpha gene by direct sequencing of polymerase chain reaction (PCR) products. A polymorphism of the TNF-beta gene (TNFB*1/TNFB*2) was detected by NCO: I restriction fragment length polymorphism analysis of PCR products spanning intron 1 and exon 2 of the TNF-beta gene.

RESULTS

None of the polymorphisms conferred susceptibility to sarcoidosis. However, our study identified the allele TNFB*1, detected by the presence of a NCO: I restriction site, as a marker of prolonged clinical course, with the resolution of sarcoidosis being defined as the disappearance of all clinical symptoms, physical signs of active lesions, abnormal chest radiograph findings, and abnormal results of pulmonary function and biochemical tests. When the probability of remission in patients homozygous for TNFB*2 was defined as 1.00, it was 0.48 (95% confidence interval, 0.26 to 0.88; p < 0.05) in patients with TNFB*1 (genotypes TNFB*1/1 and TNFB*1/2).

CONCLUSIONS

The TNFB*1 allele is a marker for prolonged clinical course in patients with sarcoidosis. Our study is the first to link a cytokine gene polymorphism to the prognosis of sarcoidosis.

The ACE gene polymorphism and cough threshold for capsaicin after cilazapril usage

Persistent dry cough is an occasional but clinically important adverse reaction to angiotensin I-converting enzyme (ACE) inhibitors (ACEI). Its reported incidence is variable, and why cough occurs in only certain individuals has been unclear. An insertion/deletion (I/D) polymorphism of the ACE gene is associated with serum ACE activity. We have previously shown that susceptibility to cough induced by ACEI is associated with this polymorphism such that patients with genotype II are more susceptible to cough than patients with other genotypes. In order to confirm and extend our previous observation, we conducted a randomized, placebo-controlled, double-blind, cross-over study in 10 healthy volunteers with genotype II and 10 with genotype DD. The cough threshold was determined by the concentration of inhaled capsaicin causing two or more coughs. After the usage of an ACEI, cilazapril, for 4 weeks, changes in the cough threshold in subjects with genotype II [before: 6.6+/-3.7 nM (mean+/-SD); after: 5.0+/-4.6 nM] significantly differed from those in subjects with genotype DD (before: 9.0+/-9.4 nM; after: 9.3+/-9.1 nM). Skin responses to intradermal bradykinin, which is a substrate of ACE and tussigenic, were significantly increased in subjects with genotype II (before: 1.6+/-0.6 vs. after: 2.6+/-0.5 cm2, P<0.05) but not in subjects with genotype DD (before: 1.4+/-0.5 vs. after: 1.6+/-0.6 cm2, n.s.) after usage of cilazapril. By contrast, skin responses to intradermal substance P did not change in subjects with either genotype. These findings provide further evidence of a link between ACEI-induced cough and I/D polymorphism of the ACE gene and suggest that ACEIs induce cough by modulating the tissue level of bradykinin.

Association between a C+33T polymorphism in the IL-4 promoter region and total serum IgE levels

Susceptibility to asthma and other atopic diseases is known to be associated with elevated total IgE levels. Several investigators have linked the interleukin-4 (IL-4) gene and nearby markers located on chromosome 5q to elevated total IgE levels. A single nucleotide polymorphism in the IL-4 gene promoter region (C+33T) has recently been identified. As part of an effort to identify genetic variants contributing to the susceptibility to elevated total serum IgE levels, an association analysis of a newly identified promoter polymorphism (C+33T) with total serum IgE levels was conducted. The study was conducted using 240 Japanese subjects (120 asthmatics and 120 healthy controls). The IL-4 C+33T polymorphism was genotyped by PCR-restriction fragment length polymorphism analysis. The frequency of the T allele was 0.675 in asthmatic subjects and 0.671 in healthy controls. An ANOVA model adjusted for age, sex and disease status suggested a genetic association of C+33T polymorphism with elevated total serum IgE levels (P < 0.05). The data suggest that IL-4 promoter C+33T polymorphism may be one of the genetic polymorphisms that explain genetic linkage or association between elevated total serum IgE levels and markers on chromosome 5q.

Macrophage migration inhibitory factor (MIF) in bronchial asthma

BACKGROUND

Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine favouring the secretion of TNFalpha and IL-8 and counteracts anti-inflammatory effects of corticosteroids. Airways inflammation is a central feature of bronchial asthma and is characterized by the accumulation of eosinophils.

OBJECTIVE

The aim of this study was to investigate whether MIF is related to asthma symptoms and eosinophil accumulation in the airways.

METHODS

Serum MIF levels were measured by an enzyme-linked immunosorbent assay in 44 healthy subjects and 44 asthmatics. Levels of MIF in induced sputum were measured in 10 healthy subjects and 15 asthmatics. Levels of eosinophil cationic protein (ECP) in induced sputum were measured by a radioimmunosorbent assay. Fluorescence double immunostaining was conducted to examine cellular source and localization of MIF.

RESULTS

Serum MIF levels were significantly increased in asthmatic patients compared with age and sex-matched control subjects. Symptomatic patients had a higher MIF level than asymptomatic patients. Induced sputum obtained from asthmatics contained higher levels of MIF than those from control subjects. MIF levels in induced sputum were correlated with ECP levels in induced sputum. MIF was colocalized with eosinophil peroxidase staining in the cytoplasm of sputum cells.

CONCLUSION

Increased MIF levels are associated with asthma symptoms and one of the cellular sources of MIF in the airways are eosinophils.

Modulatory roles of RANTES in IL-4 production by human blood CD4(+)T cells

An increase in serum IgE levels has been reported in several thrombotic cardiovascular diseases. Since such diseases are associated with the activation of platelets, we hypothesized that platelets are implicated in a mechanism leading to heightened IgE synthesis. To this end, we performed an in vitro investigation of the effects on IL-4 production caused by several bioactive substances potentially released from platelets. Human blood CD4(+)T cells from blood donors were stimulated with anti-CD3 antibody and costimulatory signals delivered via CD58 and CD80 in the presence or absence of IL-4. One of the following test substances was also included in the culture: platelet factor-4, beta-thromboglobulin, platelet-derived growth factor, serotonin, platelet activating factor, or RANTES. The cells were restimulated in the absence of IL-4 and test substances. Among the six substances, RANTES alone exhibited significant effects on IL-4 production. RANTES enhanced IL-4 production in the presence of IL-4, whereas it suppressed IL-4 production in the absence of IL-4. The enhancing effect of RANTES was positively correlated with plasma IgE levels in the donors. We concluded that RANTES may induce IgE synthesis by increasing IL-4 production in individuals predisposed to high IgE responses. Our observations indicate a link between platelets and immune phenomena associated with increased IgE responses.

Hyposensitization attenuates airway inflammation and antigen-induced proliferative response by lymphocytes in a rat model of bronchial asthma

The mechanism of hyposensitization in bronchial asthma has not been fully elucidated. We established a hyposensitization model of bronchial asthma in rats and examined airway responses and immunological parameters. Brown Norway rats were sensitized by a subcutaneous injection of ovalbumin (OA) at day 1 and by the inhalation of 2% OA aerosol at day 15. Animals were hyposensitized by intraperitoneal injections of OA from day 17 to day 22. They were challenged with OA or acethylcholine (Ach) aerosol at day 23 and changes in intratracheal pressure were recorded. Lungs were lavaged and OA-induced proliferative responses by blood lymphocytes were examined for animals without aerosol challenge at day 23. OA-specific serum IgE levels were measured by enzyme-linked immunosorbent assay. Hyposensitization significantly reduced the OA-induced immediate airway response, accumulation of CD4+ lymphocytes and eosinophils recovered by bronchoalveolar lavage, and the OA-induced proliferative response by blood lymphocytes. The airway responses to Ach and serum OA-specific IgE levels in hyposensitized group were not significantly different from those in the sensitized group. These results indicate that amelioration of airway inflammation and hyporesponsiveness of lymphocytes against OA are involved in the attenuated immediate antigen-induced airway response following hyposensitization.

Kinetics of peripheral blood stem cell collection in large-volume leukapheresis for pediatric patients undergoing chemotherapy and adult patients before chemotherapy

The present study investigated the kinetics involved in collection CD34+ cells and colony-forming units-granulocyte-macrophages (CFU-GMs) during large-volume leukapheresis (LVL) in pediatric patients with malignancies and attempted to correlate the number of cells with the processed blood volume. In addition, adult cases were also examined using the same continuous flow blood cell separator to investigate the difference between children and adults. We examined 5 pediatric patients who had undergone chemotherapy before apheresis and 3 adult patients who were scheduled to undergo chemotherapy following apheresis. Collection was performed using a continuous-flow blood cell separator. Patients received granulocyte-colony-stimulating factor (G-CSF) to mobilize peripheral blood stem cells (PBSCs), except in the case of acute myelocytic leukemia. The processed blood volume was set to approximately 300 ml in children and 500 ml/kg of body weight in adults and the leukapheresis component was collected when approximately 50 ml of blood was processed. Six sequential samples were taken from each component in pediatric patients and 10 sequential samples from adults to obtain CD34+ cells and CFU-GMs. Counts of mononuclear cells (MNCs) and CD34+ cells in peripheral blood were measured just before and after each apheresis. Hemoglobin, hematocrit, and platelet counts in peripheral blood were monitored during apheresis. A total of 11 collections were performed for pediatric patients. The mean total CD34+ cells and CFU-GMs in each fractionated yield did not show a remarkable increase with increasing volume of blood processed. In adults, the kinetics of CD34+ cells in each fractionated yield were determined on a continuous basis and CFU-GMs increased during the course of apheresis. In pediatric patients, circulating MNCs and CD34+ cells were stable during apheresis, whereas in adult patients these cells decreased in the peripheral blood after apheresis. In both pediatric and adult patients, the platelet count in the peripheral blood decreased after apheresis. In contrast to adults, in pediatric patients who had been undergone chemotherapy, the collection efficiency did not appear to increase with increased volume of blood processed. Moreover, there was a marked platelet reduction in peripheral blood following apheresis. We conclude that the kinetics of collecting PBSCs by continuous flow blood cell separator is different between pediatric cases and adults cases. The application of LVL may be prudent in some children with malignancies, including those with a low platelet count and low body weight.

Different expression of sialyl Tn antigen between polypoid and nonpolypoid growth types of advanced colorectal carcinoma

Colorectal tumors can be classified based on their growth pattern into the polypoid growth type (PG-type) and nonpolypoid growth type (NPG-type). We examined sialyl Tn antigen expression in advanced colorectal carcinomas that were classified as PG-type and NPG-type cancers in order to ascertain whether or not such expression correlates with other biologically and clinically important differences. A total of 94 advanced colorectal carcinomas were examined for sialyl Tn antigen expression, which was immunohistochemically detected by the monoclonal antibody TKH2. Univariate and multivariate analyses using logistic regression models were performed. Forty carcinomas (42.6%) were negative and 54 (57.5%) were positive for sialyl Tn antigen. Eighteen carcinomas (19.2%) were of PG type and 76 (80.8%) of NPG type. NPG-type cancers had a higher proportion of positive lymph node metastasis than PG-type cancers. Furthermore, sialyl Tn antigen was less often detected in NPG-type cancers (39 of 76; 51.3%) than in PG-type cancers (15 of 18; 83.3%; p = 0.0167). Multivariate analysis showed that two variables, lymph node metastasis and sialyl Tn antigen expression in carcinoma, were independently related to tumor growth patterns, that is NPG type and PG type. These data suggest that the difference in sialyl Tn antigen expression between two kinds of tumor growth patterns of advanced colorectal carcinomas, PG type and NPG type, may reflect different biological behaviors during tumor progression.

Gene polymorphism for microsomal epoxide hydrolase and susceptibility to emphysema in a Japanese population

Recently, it was reported that gene polymorphism for microsomal epoxide hydrolase (mEPHX), an enzyme involved in the first-pass metabolism of epoxide intermediates, was associated with susceptibility to emphysema. This association was examined in a Japanese population, performing polymerase chain reaction (PCR)-based direct sequencing and restriction fragment length polymorphism assays for variant forms of mEPHX. The subjects consisted of 79 smokers with moderate to severe emphysema diagnosed by lung computed tomography scans, 58 smokers without emphysema, with a comparable smoking history, and 114 consecutive subjects who undertook annual health checkups. The allele frequency of exon 3 Tyr113 to His113, which was reported to confer slow mEPHX activity, was substantially higher in the population control group compared with that of the Caucasian control subjects in a previous study. However, neither the genotype distribution of exon 3, nor that of exon 4 His139 to Arg139, was significantly different between the two groups of smokers. These data indicate that the gene polymorphism for mEPHX is not associated with susceptibility to emphysema in the Japanese population. The discrepancy between the two studies may be explained either by racial difference or by the selection bias of subjects in the previous study, which examined those who had only mild to moderate emphysema with lung cancer or those who were clinically diagnosed as having chronic obstructive pulmonary disease.

High serum concentrations of sialyl Tn antigen in carcinomas of the biliary tract and pancreas

Sialyl-Tn (STn) antigen is a cancer-associated carbohydrate antigen expressed in cancers of the digestive tract. In the present study, we compared the serum level of STn antigen in 14 patients with benign diseases of the biliary tract and pancreas, 15 patients with bile duct cancers, and 9 patients with cancer of the pancreas. High levels of serum STn (>45 U/ml) were frequently detected in patients with carcinoma of the biliary tract (53.3%) or pancreas (55.6%), compared with the detection of high levels in those with benign diseases (14.3%; P < 0.05). Serum levels of STn did not correlate with the presence of jaundice, cholangitis, or pancreatitis, or with the level of carcinoembryonic antigen (CEA) or carbohydrate antigen (CA) 19-9. In cancer tissues, the expression of STn antigen detected by immunostaining correlated significantly with serum STn (P < 0.05). Our results indicate that measurement of serum STn level may be potentially useful for the diagnosis of carcinomas of the biliary tract and pancreas, particularly when combined with other tumor markers such as CEA or CA19-9.

A common FCER1B gene promoter polymorphism influences total serum IgE levels in a Japanese population

Genetic factors are important in defining total serum IgE levels. Linkage analyses have localized a gene or genes that influence atopic phenotype at chromosome 11q13. Variants of the FCER1B gene have been identified, which are associated with an increased risk of developing atopy and bronchial asthma. Given uncertain functional consequences and low frequencies of these coding variants of FCER1B, we screened for new mutations using 24 subjects with atopic asthma. A common -109C/T polymorphism at the promoter region of FCER1B was identified, although no variant was found in the entire coding region. We genotyped this promoter polymorphism in 226 healthy control subjects and 226 asthmatic subjects using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. Allele frequencies were 0.697 for -109T and 0.303 for -109C in 226 healthy control subjects. No significant difference in the distribution of -109C/T polymorphism was found between asthmatic subjects and healthy control subjects. A homozygosity for the -109T allele, however, was associated with increased total serum IgE levels in 226 subjects with asthma (p = 0.0015). The strongest evidence for an association between total serum IgE levels and -109C/T polymorphism (p = 0.0004) was obtained when age at onset of asthma was incorporated into the analysis. Our findings may represent genetic heterogeneity and complex interactions between genetic and environmental components involved in the regulation of total IgE levels, providing evidence that the -109C/T polymorphism of the FCER1B promoter region is one of the genetic factors identified thus far, which affects total serum IgE levels in a Japanese population.

Expression of adhesion molecules in hepatic metastases of colorectal carcinoma: relationship to primary tumours and prognosis after hepatic resection

BACKGROUND

Adhesion molecules are closely involved in the development and growth of metastatic tumours.

METHODS

We examined the expression of two adhesion molecules in liver metastatic tumours originating from colorectal carcinomas and correlated the expression of E-cadherin (EC) and CD44 variant exon 6 (v6) in these tumours with prognosis after hepatic resection. We examined 39 primary colorectal and 44 liver metastatic tumours obtained from 39 patients and 30 non-metastatic colorectal carcinomas as controls. The expression of EC in primary colorectal carcinomas of the metastasis group was significantly lower than in the non-metastasis group (P < 0.05). The expression of EC was low in metastatic liver tumours.

RESULTS

The expression of CD44v6 in primary colorectal carcinomas of the metastasis group was significantly higher than in the non-metastasis group (P < 0.01). Expression of CD44v6 was high in metastatic liver tumours. However, there was no correlation between the expression of EC and CD44v6 or between each of these molecules and clinicopathological features of primary and metastatic tumours. Negative expression of EC and CD44v6 was a poor prognostic factor for survival after hepatic resection.

CONCLUSIONS

Our results indicate that the lack of expression of EC and CD44v6 in liver metastases of colorectal cancer is associated with poor survival after surgery.