Characterization of gut microbial and metabolite alterations in faeces of Goto Kakizaki rats using metagenomic and untargeted metabolomic approach

BACKGROUND

In recent years, the incidence of type 2 diabetes (T2DM) has shown a rapid growth trend. Goto Kakizaki (GK) rats are a valuable model for the study of T2DM and share common glucose metabolism features with human T2DM patients. A series of studies have indicated that T2DM is associated with the gut microbiota composition and gut metabolites. We aimed to systematically characterize the faecal gut microbes and metabolites of GK rats and analyse the relationship between glucose and insulin resistance.

AIM

To evaluate the gut microbial and metabolite alterations in GK rat faeces based on metagenomics and untargeted metabolomics.

METHODS

Ten GK rats (model group) and Wistar rats (control group) were observed for 10 wk, and various glucose-related indexes, mainly including weight, fasting blood glucose (FBG) and insulin levels, homeostasis model assessment of insulin resistance (HOMA-IR) and homeostasis model assessment of β cell (HOMA-β) were assessed. The faecal gut microbiota was sequenced by metagenomics, and faecal metabolites were analysed by untargeted metabolomics. Multiple metabolic pathways were evaluated based on the differential metabolites identified, and the correlations between blood glucose and the gut microbiota and metabolites were analysed.

RESULTS

The model group displayed significant differences in weight, FBG and insulin levels, HOMA-IR and HOMA-β indexes (P < 0.05, P < 0.01) and a shift in the gut microbiota structure compared with the control group. The results demonstrated significantly decreased abundances of Prevotella sp. CAG:604 and Lactobacillus murinus (P < 0.05) and a significantly increased abundance of Allobaculum stercoricanis (P < 0.01) in the model group. A correlation analysis indicated that FBG and HOMA-IR were positively correlated with Allobaculum stercoricanis and negatively correlated with Lactobacillus murinus. An orthogonal partial least squares discriminant analysis suggested that the faecal metabolic profiles differed between the model and control groups. Fourteen potential metabolic biomarkers, including glycochenodeoxycholic acid, uric acid, 13(S)-hydroxyoctadecadienoic acid (HODE), N-acetylaspartate, β-sitostenone, sphinganine, 4-pyridoxic acid, and linoleic acid, were identified. Moreover, FBG and HOMA-IR were found to be positively correlated with glutathione, 13(S)-HODE, uric acid, 4-pyridoxic acid and allantoic acid and ne-gatively correlated with 3-α, 7-α, chenodeoxycholic acid glycine conjugate and 26-trihydroxy-5-β-cholestane (P < 0.05, P < 0.01). Allobaculum stercoricanis was positively correlated with linoleic acid and sphinganine (P < 0.01), and 2-methyl-3-hydroxy-5-formylpyridine-4-carboxylate was negatively associated with Prevotella sp. CAG:604 (P < 0.01). The metabolic pathways showing the largest differences were arginine biosynthesis; primary bile acid biosynthesis; purine metabolism; linoleic acid metabolism; alanine, aspartate and glutamate metabolism; and nitrogen metabolism.

CONCLUSION

Metagenomics and untargeted metabolomics indicated that disordered compositions of gut microbes and metabolites may be common defects in GK rats.

[Two cases of herpes simplex keratitis after trans-epithelial photorefractive keratectomy]

We herein report 2 cases of herpes simplex keratitis after trans-epithelial photorefractive keratectomy. Patients' medical histories, symptoms, signs, clinical examination results, diagnosis and treatment were showed in detail. Following precision diagnosis and medical intervention, including topical and systemic antiviral treatmented for 1 to 2 weeks. The two patients were cured with full reepithelialization without corneal scar.

[Efficacy of mitomycin C 0.02% for prevention of haze after transepithelial photorefractive keratectomy for mild and moderate myopia]

Objective: To investigate the efficacy of mitomycin C (MMC) 0.02% for prevention of haze after transepithelial photorefractive keratectomy (Trans-PRK) for mild and moderate myopia. Methods: Retrospective cohort study. We reviewed medical records of 295 patients (588 eyes) who underwent Trans-PRK with or without use of MMC. There were 45 patients (90 eyes) in the mild myopia group (aged between 18 and 41 years; 37 males and 8 females; myopia diopter <3.00 D) and 250 patients (498 eyes) in the moderate myopia group (aged between 18 and 46 years; 168 males and 82 females; myopia diopter: 3.00 to 6.00 D). The two groups were divided into subgroups with MMC 0.02% and without MMC, respectively. The time of intraoperative application of MMC, if there was, was 15 s and 30 s in the mild myopia group and the moderate myopia group, respectively. The mean follow-up time was 6 months. Postoperative best corrected visual acuity (BCVA), spherical equivalent (SE) and haze were analyzed and compared using an independent Student t-test or Mann-Whitney U test between subgroups. Haze variables were compared using chi-square statistics. Results: Haze was quantified with Fantes from grade 0.5 to 4. In the mild myopia group, all haze grades were 0.5 within 3 months. The incidence of haze was 6.25% (2/32) in eyes treated with MMC and 8.62% (5/58) in eyes treated without MMC; there was no statistical significance (χ²=0.00, P>0.999). In the moderate myopia group, the incidence of haze was 9.19% (24/261) in eyes treated with MMC within 3 months; the grade was 0.5 in 91.67% (22/24) of eyes with haze and 1 in 8.33% (2/24). The incidence of haze was 29.53% (70/237) in eyes treated without MMC; the grade was 0.5 in 60.00% (42/70) of eyes with haze, 1 in 18.57% (13/70), and 2 in 5.71% (4/70) within 3 months, and 0.5 in 15.71% (11/70) after 3 months (χ²=12.36, P=0.002). In the mild myopia group, BCVA was 5.0(5.0, 5.1) versus 5.0(5.0, 5.1) in the subgroups with MMC and without MMC (Z=-0.34, P=0.733). In the moderate myopia group, BCVA was 5.0(5.0, 5.1) versus 5.0(5.0, 5.1) in the subgroups with and without MMC (Z=-2.05, P=0.040). In the mild myopia group, SE was (0.33±1.07) D versus (0.32±0.57) D in the subgroups with and without MMC (t=0.25, P=0.805). In the moderate myopia group, SE was (0.66±0.85) D versus (0.53±0.67) D in the subgroups with and without MMC (t=2.97, P=0.003). Conclusions: MMC 0.02% was effective in preventing haze after Trans-PRK in the treatment of moderate myopia. However, it was not effective in mild myopia.

Effect of berberine on hyperglycaemia and gut microbiota composition in type 2 diabetic Goto-Kakizaki rats

BACKGROUND

A recent investigation showed that the prevalence of type 2 diabetes mellitus (T2DM) is 12.8% among individuals of Han ethnicity. Gut microbiota has been reported to play a central role in T2DM. Goto-Kakizaki (GK) rats show differences in gut microbiota compared to non-diabetic rats. Previous studies have indicated that berberine could be successfully used to manage T2DM. We sought to understand its hypoglycaemic effect and role in the regulation of the gut microbiota.

AIM

To determine whether berberine can regulate glucose metabolism in GK rats via the gut microbiota.

METHODS

GK rats were acclimatized for 1 wk. The GK rats were randomly divided into three groups and administered saline (Mo), metformin (Me), or berberine (Be). The observation time was 8 wk, and weight, fasting blood glucose (FBG), insulin, and glucagon-like peptide-1 (GLP-1) were measured. Pancreatic tissue was observed for pathological changes. Additionally, we sequenced the 16S rRNA V3-V4 region of the gut microbiota and analysed the structure.

RESULTS

Compared with the Mo group, the Me and Be groups displayed significant differences in FBG (P < 0.01) and GLP-1 (P < 0.05). A significant decrease in weight and homeostatic model assessment-insulin resistance was noted in the Be group compared with those in the Me group (P < 0.01). The pancreatic islets of the Me- and Be-treated rats showed improvement in number, shape, and necrosis compared with those of Mo-treated rats. A total of 580 operational taxonomic units were obtained in the three groups. Compared to the Mo group, the Me and Be groups showed a shift in the structure of the gut microbiota. Correlation analysis indicated that FBG was strongly positively correlated with Clostridia_UCG-014 (P < 0.01) and negatively correlated with Allobaculum (P < 0.01). Body weight showed a positive correlation with Desulfovibrionaceae (P < 0.01) and a negative correlation with Akkermansia (P < 0.01). Importantly, our results demonstrated that Me and Be could significantly decrease Bacteroidetes (P < 0.01) and the Bacteroidetes/Firmicutes ratio (P < 0.01). Furthermore, Muribaculaceae (P < 0.01; P < 0.05) was significantly decreased in the Me and Be groups, and Allobaculum (P < 0.01) was significantly increased.

CONCLUSION

Berberine has a substantial effect in improving metabolic parameters and modulating the gut microbiota composition in T2DM rats.

[Methods to establishment of serum induced syndrome of liver-depression and spleen-deficiency cell model]

To explore the method of establishing a cell model of traditional Chinese medicine (TCM) syndromes, HepG2 cells were induced by human serum of liver-depression and spleen-deficiency syndrome(LDSDS) to establish a cell model of LDSDS in this research. The concentration of cells, the content of human serum in culture medium and the growth characteristics of model-cell (cell growth curve, the survival rate and apparent morphology were investigated by MTT assay and microscopy. Evaluation of syndrome cell model: metabolomics was used to analyze the human serum of normal individuals and patients with LDSDS, and cell models induced by these serums, respectively. We obtained the difference metabolites from serums and cell models of LDSDS, respectively; then compared the biomarkers from two metabolomics and their metabolic pathways, to verify that the reliability and applicability of the model. Metabolomics data were collected by UPLC-Q-TOF-MS, and then all data were analyzed by multivariate statistical (PCA，OPLS-DA). The results showed that, model cells have the characteristics of normal growth, slow proliferation and stable morphological structure inducted by 10% serum of LDSD in 24-72 h. There were the same 19 difference metabolites which from the human serum of normal individuals and patients with LDSDS, and cell models induced by these serums; including 9 metabolic pathways that play an important role in maintaining normal physiological activities of the human body, such as lipids, amino acids, nucleotides, and energy metabolism etc. It was shown that the established syndrome cell model can reflect the biological basis of LDSDS to some extent. This research provides a reference method for the establishment of TCM syndrome cell model.

[Clinical significance of continuous transfixion suture for nasal septum in septoplasty]

Objective:To systemically evaluate the clinical significance of continuous transfixion suture for nasal septum in septoplasty. Method:Forty patients with nasal septum deviation were randomly assigned to the suture group including 20 patients who underwent endoscopic septoplasty followed by continuous transfixion suture for nasal septum, or the nasal packing group including 20 patients who underwent endoscopic septoplasty followed by nasal packing. Two groups were compared for the visual analogue scale (VAS) scores for postoperative rhinalgia, headache, lacrimation, dysphagia and sleep disorder, changes in mucociliary transport time (MTT) before and after surgery, and postoperative capillary hemorrhage. Patients were followed up for 2 weeks to observe the short-term postoperative complications. Result:Mean VAS scores for rhinalgia, headache, lacrimation, dysphagia and sleep disorder were all higher in nasal packing group than those in suture group (P<0.05); compared to suture group, there was greater prolongation of MTT before and after surgery in packing group (P<0.05); there was significant difference between two groups in postoperative capillary hemorrhage volume (P<0.05); in the nasal packing group, nasal synechia, nasal dryness and hyposmia were observed in 1, 3 and 2 patients, respectively, within 2 weeks postoperatively, whereas no short-term complications were observed in the suture group. Conclusion:Use of continuous transfixion suture in place of nasal packing following septoplasty can significantly improve the postoperative symptoms, protect nasal mucociliary clearance, and reduce short-term postoperative complications.

[Value discussion of radical sinus surgery for difficult-to-treat rhinosinusitis]

Objective:To investigate the efficacy of radical sinus surgery (RSS) on difficult-to-treat rhinosinusitis(DTRS) with nasal polyps. Method: We retrospectively analyzed the clinical data of 26 patients with DTRS that treated with RSS and patients who were not treated with RSS in our hospital from August 2013 to June 2017.The effect of RSS were evaluated by comparing the CT Lund-Kennery score,endoscope Lund-Kennery score,global VAS score and dysosmia VAS score before operation and 6 months after operation. Result: RSS group had more severe Lund-Kennery score,global VAS score and dysosmia VAS score than non-RSS group,and also had more previous surgeries,higher ratio of olfactory region polyps,and higher ratio of co-existing asthma and allergic rhinitis. However RSS group had a lower ratio with pus anot than non-RSS group. The eosinophil count in periheral blood between two groups had no statistical significance. Six months after RSS,the score of endoscope Lund-Kennery,global VAS and dysosmia VAS dependence. 14 patients were successfully cured(53.8%), 12 patients showed improvement(46.2%), no invalid cases. Conclusion: The global symptoms and olfaction of DTRS patients can be improved by RSS combine individual perioperative drug therapy.

[Research progress in therapeutic action of mesenchymal stem cell in allergic rhinitis]

Allergic rhinitis (AR) is an allergic disease of nasal mucosa, currently the consensus has been reached that there is a Th1/Th2 imbalance in AR's pathogenesis, meanwhile there are defects in the number and/or function of Treg cells. Mesenchymal stem cells (MSCs) have characteristics of multiple differentiation potential, low immunogenicity and immunomodulation function, which can be migrated and implanted into the nasal inflammatory mucosal, recovering the Th1/Th2 immune balance and up-regulate the Treg cells by immunomodulatory function to improve AR. For the present, the treatment of AR by MSCs is basically at the animal experiment stage. This paper reviews the progress of MSCs in AR's treatment and provides a basis for the clinical treatment of MSCs.

Large-scale screening and characterisation of Lemna aequinoctialis and Spirodela polyrhiza strains for starch production

Duckweed is considered a promising feedstock for bioethanol production due to its high biomass and starch production. Selection of duckweed strains with high starch accumulation is essential for application of duckweeds to bioethanol production. Geographic differentiation had a large influence on genetic diversity of duckweeds. Biomass production, starch content and starch amount in geographically isolated strains of 20 Lemna aequinoctialis and Spirodela polyrhiza were calculated to evaluate their potential for bioethanol production. The influence of different collection time, culture medium and NaCl concentration on starch accumulation of the best strains were analysed. The results showed that biomass production, starch content and starch production of duckweeds demonstrated clonal dependency. The best strain was L. aequinoctialis 6000, with biomass production of 15.38 ± 1.47 g m^-2 , starch content of 28.68 ± 1.10% and starch production of 4.39 ± 0.25 g m^-2 . Furthermore, starch content of L. aequinoctialis 6000 was highest after 8 h of light, tap water was the best medium for starch induction, and NaCl did not induce starch accumulation. This study suggests duckweed biomass production and starch production demonstrate clonal dependency, indicating that extensive clonal comparisons will be required to identify the most suitable isolates for duckweed selective breeding for bioethanol.

[RNA interference targeting DNA-PKcs inhibits glioma cells malignancies and enhances temozolomide sensitivity]

Objective: To investigate the effect of DNA dependent protein kinase catalytic subunit (DNA-PKcs) on glioma proliferation, invasion and temozolomide sensitivity, and also to explore the potential mechanisms. Methods: Human glioma cell lines H4 and U87 were chosen to carry out RNA interference transfection, and then divided into negative control group (blank group) and siRNA group (test group). The knockdown efficacy of DNA-PKcs siRNA was tested by quantitative PCR and Western blot. The MTS assay and Transwell assay were used to investigate the effect of DNA-PKcs knockdown on glioma cell growth and invasion, respectively. We also used MTS assay to investigate the IC(50) value of temozolomide in negative control group and siRNA groups. Result: Compared with blank group, DNA-PKcs specific siRNA significantly downregulated both mRNA and protein level of DNA-PKcs. MTS assay results demonstrated that 72-hours proliferation of test group were only 52.48%, 54.70% (H4) and 52.98%, 50.45% (U87) of the blank group's counterpart. Transwell assay results showed that the invasiveness abilities of blank and test groups were 1.00±0.03, 0.41±0.05, 0.39±0.04 (H4) and 1.00±0.02, 0.28±0.04, 0.27±0.04 (U87). Moreover, knockdown of DNA-PKcs significantly decreased the temozolomide IC(50) value (H4: 249±27, 97±39, 88±35; U87: 485±41, 86±49, 73±38). Further we applied the Western blot to reveal the mechanism of inhibitory effect of DNA-PKcs knockdown on glioma malignancies and temozolomide sensitivity. We found that downregulation of DNA-PKcs reduced the activity of AKT signal and the expression of its downstream effectors, such as c-Myc, MMP9, and Survivin. Conclusion: RNA interference targeting DNA-PKcs could inhibit glioma malignancies and enhance temozolomide sensitivity. The inhibitory effect of DNA-PKcs knockdown on those biological activities were mainly through inhibition of AKT signal and its downstream effectors.

[Comparison of the anterior corneal asphericity after small incision lenticule extraction and femtosecond laser in situ keratomileusis]

OBJECTIVE

To evaluate and compare the anterior corneal asphericity after small incision lenticule extraction(SMILE)and femtosecond laser in situ keratomileusis(FS-LASIK).

METHODS

In this case-control study, 45 subjects who underwent SMILE operation comprised the study group, and 33 subjects with FS-LASIK operation comprised the control group. The asphericity coefficient Q-value of the right eyes in both groups was measured at diameters of 6, 7, 8 and 9 mm, respectively, before surgery and at 1 day, 1 week, 1 month and 6 months following surgery. The correlation between the variation of Q-value and the central cutting depth was analyzed.

RESULTS

The Q-value of anterior corneal surface was 0.85 ± 0.31, 0.80±0.28, 0.69±0.25 and 0.51±0.23 after SMILE, and 1.13±0.56, 1.01±0.47, 0.80±0.39 and 0.51±0.31 after FS-LASIK at 1 week. In both groups, the Q-value was significantly different before and after surgery(P< 0.05); there were interaction effects between the operation method and time; the difference between the two groups at 6-mm and 7-mm diameters was statistically significant(P<0.05). The variation of the Q-value before and after operation(ΔQ)showed significant difference(P6mm=0.004, P7mm=0.014)between the two groups at 6-mm and 7-mm diameters. The cap diameter of the SMILE group was smaller than that of the FS-LASIK group, but the cutting depth was larger. There was no correlation between ΔQ and the cap/disc diameter. It showed a linear relationship(P<0.05)between ΔQ and the central cutting depth at all examined diameters in the two groups, and the relation degree in the FS-LASIK group was superior to the SMILE group.

CONCLUSIONS

Both SMILE and FS-LASIK operations can change the negative Q-value of the anterior corneal surface to the positive. The impact of SMILE on the asphericity is smaller than that of FS-LASIK. (Chin J Ophthalmol, 2016, 52: 681-685).

[An analysis of changes in posterior corneal elevation and relevant factors after small incision lenticule extraction]

OBJECTIVE

To investigate changes in posterior corneal elevation after small incision lenticule extraction (SMILE) and related factors.

METHODS

Retrospective case series study. Eighty-three eyes of 44 myopic patients undergoing SMILE were examined with the Pentacam preoperatively, and at 1 day, 1 month, 3 months, and 6 months postoperatively. Posterior corneal elevation at the corneal apex and 0°, 45°, 90°, 135°, 180°, 225°, 270° and 325° points of the 2 mm and 6 mm diameter (total, 17 points) was analyzed.

RESULTS

The changes in posterior corneal elevation at 1 day, 1 month, 3 months, and 6 months were(-1.72±2.59), (-0.98±2.37), (-0.45±1.81) and (-0.25±2.20) μm, respectively, at the corneal apex. The results were statistically significant (t=6.07, 3.75, 6.07; P<0.05), except 6 months. The changes in posterior corneal elevation were (-1.42±2.06),(-0.69±1.86), (-0.30±1.50) and(-0.22±1.58) μm, respectively, in the 2 mm circle. The results of 1 day and 1 month were statistically significant (t=6.28, 6.28, P<0.05). The changes in posterior corneal elevation were (1.48±1.47),(0.98±1.32),(0.90±1.31) and (0.90±1.16) μm, respectively, in the 6 mm circle .The results were totally statistically significant (t=6.28, 6.28, P<0.05). There were statistically significant differences between 1 month and 1 day postoperatively in the corneal apex, 2 mm and 6 mm circles. The changes were (0.75±2.55),(0.73±1.97) and(-0.50±1.60) μm. There were statistically significant differences between 3 months and 1 month postoperatively in the corneal apex and 2 mm circle. The changes were (0.53±2.22) and (0.39±1.80) μm. No significant change was found in the 6 mm circle. Between postoperative 6 months and 3 months, there were no statistically significant differences. The spherical equivalent, intraocular pressure, ablation depth, residual bed thickness, corneal hysteresis, and corneal resistance factor had no obvious correlation with the changes in posterior corneal elevation.

CONCLUSIONS

After SMILE, the surrounding cornea was slightly forward, while the central posterior cornea was slightly backwards, and returned gradually. The spherical equivalent, intraocular pressure, ablation depth, residual bed thickness, corneal hysteresis, and corneal resistance factor had no obvious correlation with the changes in posterior corneal elevation. (Chin J Ophthalmol, 2016, 52: 494-498).

Correlation between CO2 storage at the last minute of gas insufflation and area of retroperitoneal lacuna during retroperitoneal laparoscopic radical nephrectomy

Background

Adequate operation interspace is the premise of laparoscopy, and carbon dioxide (CO₂) was an ideal gas for forming lacuna. A retroperitoneal space is used to form operation interspace in retroperitoneal laparoscopic radical nephrectomy by making ballooning, and the retroperitoneal space has no relative complete and airtight serous membrane, therefore CO₂ absorption may be greater in retroperitoneal than transperitoneal laparoscopic radical nephrectomy. Excess CO₂ absorption may induce hypercapnemia and further cause physiopathological change of respiratory and circulatory system. Therefore, exact evaluation of amount of CO₂ which is eliminated from body via minute ventilation is important during retroperitoneal laparoscopic radical nephrectomy. The aim of the paper is to study the correlation between CO2 storage at the last minute of gas insufflation and area of retroperitoneal lacuna during retroperitoneal laparoscopic radical nephrectomy.

Methods

Forty ASA I/II patients undergoing retroperitoneal laparoscopic radical nephrectomy were enrolled. CO₂ storage at the last minute of gas insufflation and area of a retroperitoneal lacuna were observed. Linear correlation and regression were performed to determine the correlation between them.

Results

There was positive correlation between CO₂ storage at the last minute of gas insufflation and area of retroperitoneal lacuna (r = 0.880, P = 0.000), and the equation of linear regression was y = −83.097 + 0.925x (R² = 0.780, t = 11.610, P = 0.000).

Conclusions

Amount of CO₂ which is eliminated from body via mechanical ventilation could be calculated by measuring the area of retroperitoneal lacuna during retroperitoneal laparoscopic radical nephrectomy, and an anesthetist should be aware of the size of lacuna to predict high CO₂ storage at the last minute of gas insufflation.

Elevated survivin mediated multidrug resistance and reduced apoptosis in breast cancer stem cells

PURPOSE

Overexpression of survivin in breast cancer cells is associated with aberrant inhibition of apoptosis which leads to massive proliferation of cancer cells. Downregulation of survivin by the anticancer agent prodigiosin can efficiently induce apoptosis in cancer cells.

METHODS

The levels of survivin expression in breast cancer stem like side population (SP) cells were assessed. Analyzed were also the rate of apoptosis, drug resistance and the efficiency of clone formation of breast cancer SP cells after treatment with progiosin.

RESULTS

Breast cancer samples contained about 2.7% of cancer stem like SP cells which possessed elevated mRNA expression of stem cell proteins Oct-4, EpCAM and ABC transporter ABCG2, essential for the maintenance of SP cells. Furthermore, the SP cells displayed overexpression of survivin in conjunction with reduced apoptosis and increased multidrug resistance. After treatment with prodigiosin, the SP cells became more sensitive to apoptosis and to several chemotherapeutic agents.

CONCLUSION

These data suggest that increased expression of survivin in SP cells is one of the major factors involved in apoptosis and resistance to chemotherapy.

S100A8 contributes to postoperative cognitive dysfunction in mice undergoing tibial fracture surgery by activating the TLR4/MyD88 pathway

Neuro-inflammation plays a key role in the occurrence and development of postoperative cognitive dysfunction (POCD). Although S100A8 and Toll-like receptor 4 (TLR4) have been increasingly recognized to contribute to neuro-inflammation, little is known about the interaction between S100A8 and TLR4/MyD88 signaling in the process of systemic inflammation that leads to neuro-inflammation. Firstly, we demonstrated that C57BL/6 wide-type mice exhibit cognitive deficit 24h after the tibial fracture surgery. Subsequently, increased S100A8 and S100A9 expression was found in the peripheral blood mononuclear cells (PBMCs), spleen, and hippocampus of C57BL/6 wide-type mice within 48h after the surgery. Pre-operative administration of S100A8 antibody significantly inhibited hippocampal microgliosis and improved cognitive function 24h after the surgery. Secondly, we also observed TLR4/MyD88 activation in the PBMCs, spleen, and hippocampus after the surgery. Compared with those in their corresponding wide-type mice, TLR4(-/-) and MyD88(-/-) mice showed lower immunoreactive area of microglia in the hippocampal CA3 region after operation. TLR4 deficiency also led to reduction of CD45(hi)CD11b(+) cells in the brain and better performance in both Y maze and open field test after surgery, suggesting a new regulatory mechanism of TLR4-dependent POCD. At last, the co-location of S100A8 and TLR4 expression in spleen after operation suggested a close relationship between them. On the one hand, S100A8 could induce TLR4 activation of CD11b(+) cells in the blood and hippocampus via intraperitoneal or intracerebroventricular injection. On the other hand, TLR4 deficiency conversely alleviated S100A8 protein-induced hippocampal microgliosis. Furthermore, the increased expression of S100A8 protein in the hippocampus induced by surgery sharply decreased in both TLR4 and MyD88 genetically deficient mice. Taken together, these data suggest that S100A8 exerts pro-inflammatory effect on the occurrence and development of neuro-inflammation and POCD by activating TLR4/MyD88 signaling in the early pathological process of the postoperative stage.

Isolated familial pneumothorax in a Taiwanese family with Birt-Hogg-Dubé syndrome

Primary spontaneous pneumothorax usually occurs as a sporadic event, but may be clustered in certain families with an underlying inherited disorder. Birt-Hogg-Dubι (BHD) syndrome is a rare autosomal dominant disease accounting for familial pneumothorax. BHD syndrome, caused by mutation of the folliculin gene, is characterized by skin fibrofolliculoma, pulmonary cysts, pneumothorax, and renal cancer. We describe a BHD-affected Taiwanese family with clinical and genetic study. A rare mutation of the folliculin gene was detected in the patient and members with pulmonary cysts or pneumothorax, but no skin or renal lesions were found. This mutation was reported in a Taiwanese family and might indicate a pneumothorax-predominant phenotype. Isolated pneumothorax is an uncommon initial presentation of BHD syndrome. Family history should be carefully reviewed when managing a patient with pneumothorax.

Factors associated with adherence to low-tidal volume strategy for acute lung injury and acute respiratory distress syndrome and their impacts on outcomes: an observational study and propensity analysis

BACKGROUND

The purpose of this study was to investigate the factors affecting adherence to the low-tidal volume (LTV) strategy in acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) and their impacts on outcomes.

METHODS

This prospective observational study included 111 patients with ALI/ARDS admitted to six intensive care units between March 2010 and February 2011. The patients were divided into the LTV group, which received a TV ≤7.5 mL/kg predicted body weight (PBW), and the non-LTV group, which received a TV >7.5 mL/kg PBW. We studied the association of selected clinical factors and adherence to the LTV strategy, and evaluated their impacts on 28-day mortality and 1-year mortality by the propensity-match process.

RESULTS

Adherence to the LTV strategy was only 44%, which was related to lung injury severity (odds ratio [OR]: 3.15, P=0.038), muscle relaxant use (OR: 3.28, P=0.031), and depth of sedation (OR: 0.65, P=0.008). Propensity score-based analysis showed that the LTV group had modestly better 28-day survival (P=0.081) and 1-year survival (P=0.067) than the non-LTV group. Moreover, muscle relaxant use was strongly associated with reducing the risk of death at both 28 days (hazard ratio [HR]: 0.122, 95% confidence interval [CI]: 0.027-0.542, P=0.006) and 1 year ([HR]: 0.111, 95% [CI]: 0.030-0.408, P=0.001).

CONCLUSION

Adherence to the LTV strategy was strongly associated with the lung injury score, muscle relaxant use, and depth of sedation. Propensity score-based analysis showed that the use of LTV ventilation and muscle relaxants reduced 28-day and 1-year mortality in ALI/ARDS patients.

Effect of the beta secretase-1 inhibitor on the amyloid C-terminal fragment of amyloid precursor protein processing in a hyperphosphorylated tau rat model

The amyloid C-terminal fragment (βCTF) of the amyloid precursor protein (APP) is the cleaved component of APP by beta secretase-1 (BACE1), which shows similar neurotoxicity as amyloid beta (Aβ) in many ways. Evidence suggested that in addition to Aβ, βCTF might also participate in the pathogenesis of Alzheimer's disease (AD). In recent years, the relationship between βCTF processing and hyperphosphorylated tau has attracted increasing research attention. In this study, we established an animal model of tau hyperphosphorylation with okadaic acid (OA) treatment, and analyzed βCTF processing in vivo. The βCTF level was found to increase in neurons, which was most likely caused by the induction of OA and BACE1 overexpression. Furthermore, these results provide the first evidence that βCTF can predominately accumulate in the axons of neurons in a hyperphosphorylated tau state in vivo, and suggested that the redistribution of βCTF is involved in the pathogenesis of AD. These results indicate that BACE1 could be a therapeutic target of AD by affecting the processing of βCTF.

Elastase induced lung epithelial cell apoptosis and emphysema through placenta growth factor

Chronic pulmonary obstructive disease (COPD) is the fourth leading cause of death worldwide, however, the pathogenic factors and mechanisms are not fully understood. Pulmonary emphysema is one of the major components of COPD and is thought to result from oxidative stress, chronic inflammation, protease–antiprotease imbalance and lung epithelial (LE) cell apoptosis. In our previous studies, COPD patients were noted to have higher levels of placenta growth factor (PlGF) in serum and bronchoalveolar lavage fluid than controls. In addition, transgenic mice overexpressing PlGF developed pulmonary emphysema and exposure to PlGF in LE cells induced apoptosis. Furthermore, intratracheal instillation of porcine pancreatic elastase (PPE) on to PlGF wild type mice induced emphysema, but not in PlGF knockout mice. Therefore, we hypothesized that PPE generates pulmonary emphysema through the upregulation of PlGF expression in LE cells. The elevation of PlGF then leads to LE cell apoptosis. In the present study, we investigated whether PPE induces PlGF expression, whether PlGF induces apoptosis and whether the downstream mechanisms of PlGF are related to LE cell apoptosis. We found that PPE increased PlGF secretion and expression both in vivo and in vitro. Moreover, PlGF-induced LE cell apoptosis and PPE-induced emphysema in the mice were mediated by c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38 MAPK) pathways. Given these findings, we suggest that the increase in PlGF and PlGF-induced JNK and p38 MAPK pathways contribute to PPE-induced LE cell apoptosis and emphysema. Regulatory control of PlGF and agents against its downstream signals may be potential therapeutic targets for COPD.

X-ray reflectivity study on the structure and phase stability of mixed phospholipid multilayers

Vertically oriented multilayers composed of two saturated phospholipids, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphoserine (DPPS), were deposited on silicon. X-ray reflectivity was used to investigate the structures of the variously mixed phospholipid multilayers as a function of composition. Then, the phase stability was investigated at various annealing temperatures under humid conditions. The results indicated that the lipid spacing of the mixed phospholipid multilayers varied systematically as a function of the DPPC/DPPS ratio and that no macroscopic phase separation occurred during the annealing process under both dry and humid conditions.

Pandrug-resistant Pseudomonas aeruginosa among hospitalised patients: clinical features, risk-factors and outcomes

Between 1 January 2003 and 31 December 2003, 37 patients had positive cultures of pandrug-resistant Pseudomonas aeruginosa (PDRPA) resistant to all commercially available anti-pseudomonal antimicrobial agents in Taiwan, including anti-pseudomonal penicillins, ceftazidime, fourth-generation cephalosporins, aztreonam, carbapenems, aminoglycosides and ciprofloxacin. Nineteen (51.4%) patients had PDRPA infections, including pneumonia (17 patients), catheter-related bacteraemia (one patient) and anal abscess (one patient). Eighteen patients were classified as having PDRPA colonisation, based on absence of clinical signs or symptoms of infection. In total, 92 isolates were recovered from various specimens, with the majority (85.9%) recovered from respiratory tract secretions (sputa, bronchial washings and pleural effusions), followed by urine (4.3%) and catheter tips (3.3%). Twenty-eight (75.7%) patients yielded cultures of non-PDR P. aeruginosa isolates before isolation of PDRPA, with a mean period between the first isolation of non-PDR P. aeruginosa and the isolation of PDRPA of 128.3 days. Most patients had received beta-lactam antibiotics, fluoroquinolones or carbapenems for prolonged periods. Univariate analysis showed that PDRPA infection, male gender and the presence of fever at the time of PDRPA isolation were associated with increased mortality.

Formation and removal of alkylthiolate self-assembled monolayers on gold in aqueous solutions

We report the development of novel reagents and approaches for generating recyclable biosensors. The use of aqueous media for the formation of protein binding alkylthiolate monolayers on Au surfaces results in accelerated alkylthiolate monolayer formation and improvement in monolayer integrity as visualized by fluorescence microscopy and CV techniques. We have also developed an electrocleaning protocol that is compatible with microfluidics devices, and this technique serves as an on-chip method for cleaning Au substrates both before and after monolayer formation. The techniques for the formation and dissociation of biotinylated SAMs from aqueous solvents reported here may be applied towards the development of Au-based sensor devices and microfluidics chips in the future. A potential use of these devices includes the specific capture and triggered release of target cells, proteins, or small molecules from liquid samples.

Minicraniotomy treatment of an intracerebral epidermoid cyst

Intracerebral epidermoid cysts are extremely rare. We report the case of a 16-year-old girl with an intracerebral epidermoid cyst in the left temporal lobe. The lesion was totally removed through a minimally invasive minicraniotomy by which we could obtain satisfactory intraoperative disclosure and manipulation. The incidence, clinical course, radiological features, surgical treatment, and complications of such a rare lesion are discussed.

Interfacial Electron-Transfer Kinetics of Ferrocene through Oligophenyleneethynylene Bridges Attached to Gold Electrodes as Constituents of Self-Assembled Monolayers: Observation of a Nonmonotonic Distance Dependence

The standard heterogeneous electron-transfer rate constants (k(n)0) between substrate gold electrodes and the ferrocene redox couple attached to the electrode surface by variable lengths of substituted or unsubstituted oligophenyleneethynylene (OPE) bridges as constituents of mixed self-assembled monolayers were measured as a function of temperature. The distance dependences of the unsubstituted OPE standard rate constants and of the preexponential factors (An) obtained from an Arrhenius analysis of the unsubstituted OPE k(n)0 versus temperature data are not monotonic. This surprising result, together with the distance dependence of the substituted OPE preexponential factors, may be assessed in terms of the likely conformational variability of the OPE bridges (as a result of the low intrinsic barrier to rotation of the phenylene rings in these bridges) and the associated sensitivity of the rate of electron transfer (and, hence, the single-molecule conductance which may be estimated using An) through these bridges to the conformation of the bridge. Additionally, the measured standard rate constants were independent of the identity of the diluent component of the mixed monolayer, and using an unsaturated OPE diluent has no effect on the rate of electron transfer through a long-chain alkanethiol bridge. These observations indicate that the diluent does not participate in the electron-transfer event.

Genetic polymorphism of epoxide hydrolase and glutathione S-transferase in COPD

Genetic susceptibility to the development of chronic obstructive pulmonary disease (COPD) might depend on variation in the activities of enzymes that detoxify cigarette smoke products, such as microsomal epoxide hydrolase (mEPHX) and glutathione S-transferase (GST). It was investigated whether polymorphisms in these genes had any association with susceptibility to COPD and COPD severity. The genotypes of 184 patients with COPD and 212 control subjects were determined by polymerase chain reaction followed by restriction fragment length polymorphism analysis of the mEPHX, GSTM1, GSTT1 and GSTP1 genes. All subjects were smokers or exsmokers. The proportion of GSTM1-null genotypes was significantly higher in patients with COPD than in control subjects (61.4 versus 42.5%). No differences were observed in the frequency of polymorphic genotypes for mEPHX, GSTT1 and GSTP1. During combined analysis of genetic polymorphisms for mEPHX, GSTM1 and GSTP1, it was found that there are strong indicators for susceptibility to COPD (genotype combination with at least one mutant mEPHX exon-3 allele (histidine 113), GSTM1 null and homozygous for the GSTPI isoleucine 105 allele). The frequencies of homozygous mutant alleles of mEPHX exon 3 and the GSTMI-null genotype were significantly higher in patients with severe COPD (forced expiratory volume in one second of <35% of the predicted value). It is proposed that the combination of genetic variants including at least one mutant microsomal epoxide hydrolase exon-3 allele and glutathione S-transferase M1-null and homozygous isoleucine 105 glutathione S-transferase P1 genotypes are significant indicators of susceptibility to chronic obstructive pulmonary disease in the Taiwanese population. In addition, the homozygous variant of microsomal epoxide hydrolase exon 3 and the glutathione S-transferase M1-null genotype are independent risk factors for developing severe chronic obstructive pulmonary disease.

Structural characterization of thin hydroxypropylcellulose films. X-ray reflectivity studies

Thin solid films of hydroxypropylcellulose (HPC) have been investigated using synchrotron X-ray reflectivity. Evidence of preferential alignment of HPC molecules at the substrate surface is obtained. In the surface region the liquid crystalline domains ofHPC are preferentially oriented parallel to the substrate, whereas in the bulk they are mostly distributed randomly. Incorporation of colloidal particles in the film-substrate region destroys the preferential alignment. It is also found that in conditions of restricted geometry (very thin films), a minimum film thickness is required to produce lateral packing order perpendicular to the substrate surface.

Patient mortality of active pulmonary tuberculosis requiring mechanical ventilation

Mortality remains high among patients with pulmonary tuberculosis requiring mechanical ventilation (TBMV). This study was carried out to establish the mortality rates of TBMV and to identify factors that contribute to in-hospital mortality. From January 1996-April 2001, there were 825 patients with active pulmonary tuberculosis at the National Taiwan University Hospital, Taipei, Taiwan. Of these, 41 suffered acute respiratory failure and required mechanical ventilation in the intensive care unit (ICU). Of these 41 patients, 38 were followed up for 180 days. In-hospital deaths were documented in the medical records and all possible parameters contributing to mortality were collected. Of the 41 patients, 27 died in the hospital and 14 were discharged alive (in-hospital mortality rate 65.9%), with (mean +/- SD) 40.7 +/- 35.4 admission days before death. Of the 27 that died, 25 died during ICU admission and two died after being transferred to the ward. The mortality rate for the 180-day monitoring period was 79%. Factors contributing to in-hospital mortality included consolidations on chest radiographs and multiple organ failure. The mortality rate in the patients with pulmonary tuberculosis requiring mechanical ventilation is very high, with two factors affecting in-hospital mortality. These factors were multiple organ failure and consolidation on chest radiographs.

Electronic detection of single-base mismatches in DNA with ferrocene-modified probes

Genotyping and gene-expression monitoring is critical to the study of the association between genetics and drug response (pharmacogenomics) and the association of sequence variation with heritable phenotypes. Recently, we developed an entirely electronic method for the detection of DNA hybridization events by the site-specific incorporation of ferrocenyl derivatives into DNA oligonucleotides. To perform rapid and accurate point mutation detection employing this methodology, two types of metal-containing signaling probes with varying redox potentials are required. In this report we describe a new ferrocene-containing phosphoramidite 9 that provides a range of detectable redox potentials. Using automated DNA/RNA synthesis techniques the two ferrocenyl complexes were inserted at various positions along oligonucleotide probes. Thermal stability analysis of these metal-containing DNA oligonucleotides indicates that incorporation of 9 resulted in no destabilization of the duplex. A mixture of oligonucleotides containing compounds 9 and I was analyzed by alternating current voltammetry (ACV) monitored at the 1st harmonic. The data demonstrate that the two ferrocenyl oligonucleotide derivatives can be distinguished electrochemically. A CMS-DNA array was prepared on an array of gold electrodes on a printed circuit board substrate with a self-assembled mixed monolayer, coupled to an electronic detection system. Experiments for the detection of a single-base match utilizing two signaling probes were carried out. The results demonstrate that rapid and accurate detection of a single-base mismatch can be achieved by using these dual-signaling probes on CMS-DNA chips.

Application of mucin quantitative competitive reverse transcription polymerase chain reaction in assisting the diagnosis of malignant pleural effusion

Aberrant expression of mucin genes occurs frequently in advanced cancer. Using quantitative competitive reverse transcriptase/polymerase chain reaction (QC RT-PCR), the expression of three mucin genes--MUC1 (widely expressed in epithelial cells), MUC2 (mainly expressed in intestinal epithelial cells), and MUC5AC (mainly from airway and gastric epithelial cells)--was evaluated in 112 patients with pleural effusions (including 54 cytologically positive malignant pleural effusions, 35 benign exudative pleural fluids, and 23 cytologically negative pleural effusions from cancer patients). The expression ratios of MUC1 and MUC5AC, but not MUC2 gene, were significantly higher in malignant than benign pleural fluids (p < 0.000). The cutoff value, sensitivity, and specificity of MUC1 expression ratio were: 0.126, 64.6%, and 95.7%; and were 0.028, 72.3%, and 95.7%, respectively, for MUC5AC. In combined evaluation with both MUC1 and MUC5AC, the sensitivity was 86.1% and specificity was 91.5%. The positive and negative predictive values were 93.3%, and 82.7%, respectively. We considered mucin QC RT-PCR to be a useful tool in assisting the diagnosis of malignant pleural effusion.

Severe community-acquired pneumonia due to Acinetobacter baumannii

STUDY OBJECTIVES

To investigate the clinical, epidemiologic, and microbiological characteristics of community-acquired pneumonia (CAP) due to Acinetobacter baumannii.

METHODS

Retrospective chart and radiographic reviews of all patients who were admitted to National Taiwan University Hospital from January 1993 to August 1999, fulfilled the criteria for CAP, and had an isolate of A. baumannii from blood or pleural fluid at hospital admission.

RESULTS

Thirteen patients (9 men and 4 women; age range, 37 to 85 years) met the criteria. Conditions associated with the infection included male gender, old age, alcoholism, malignancy, cerebrovascular disease, diabetes mellitus, renal disease, and liver cirrhosis. Eleven patients (85%) acquired the infection during the warmer months of April to October. Twelve patients (92%) had a fulminant course presenting with septic shock and respiratory failure, and 11 patients (85%) needed ventilator support and were treated in an ICU. Six patients (46%) had leukopenia. Lobar consolidations were found in 12 patients (92%), and pleural effusions were present in 4 patients (31%). All patients had positive blood culture results, two patients (15%) had positive pleural effusion culture findings, and nine patients (69%) positive sputum culture results. All the isolates were susceptible to imipenem, and most were susceptible to aminoglycosides, ceftazidime, ciprofloxacin, and extended-spectrum penicillins. Eight patients (62%) died. Four of the five survivors were initially treated with combination of a third-generation cephalosporin and an aminoglycoside.

CONCLUSION

A. baumannii should be considered as a possible etiologic agent in community-acquired lobar pneumonia when (1) patients with a fulminant course present during the warmer and more humid months of the year, and (2) patients are younger alcoholics. A good sputum smear, defined as a Gram stain smear of an adequate sputum specimen that comes from the lower respiratory tract and contains > 25 leukocytes per high-power (100x) field on microscopic examination, can help early diagnosis and treatment. A combination of a third-generation cephalosporin and an aminoglycoside may be appropriate empirical therapy.

Collapsin response mediator protein-1 and the invasion and metastasis of cancer cells

BACKGROUND

Numerous genetic changes are associated with metastasis and invasion of cancer cells. To identify differentially expressed invasion-associated genes, we screened a panel of lung cancer cell lines (CL(1-0), CL(1-1), CL(1-5), and CL(1-5)-F(4) in order of increasing invasive activity) for such genes and selected one gene, collapsin response mediator protein-1 (CRMP-1), to characterize.

METHODS

We used a microarray containing 9600 gene sequences to assess gene expression in the cell panel and selected the differentially expressed CRMP-1 gene for further study. We confirmed the differential expression of CRMP-1 with northern and western blot analyses. After transfecting and overexpressing CRMP-1 in highly invasive CL(1-5) cells, the cells were assessed morphologically and with an in vitro invasion assay. We used enhanced green fluorescent protein-tagged CRMP-1 and fluorescence microscopy to localize CRMP-1 intracellularly. CRMP-1 expression in 80 lung cancer specimens was determined by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR). All statistical tests were two-sided.

RESULTS

Expression of CRMP-1 was inversely associated with invasive activity in the cell panel, an observation confirmed by northern and western blot analyses. CRMP-1-transfected CL(1-5) cells became rounded and had fewer filopodia and statistically significantly lower in vitro invasive activity than untransfected cells (all P< .001). During interphase, CRMP-1 protein was present uniformly throughout the cytoplasm and sometimes in the nucleus; during mitosis, CRMP-1 was associated with mitotic spindles, centrosomes, and the midbody (in late telophase). Real-time RT-PCR of lung cancer specimens showed that reduced expression of CRMP-1 was statistically significantly associated with advanced disease (stage III or IV; P = .010), lymph node metastasis (N1, N2, and N3; P =.043), early postoperative relapse (P = .030), and shorter survival (P = .016).

CONCLUSIONS

CRMP-1 appears to be involved in cancer invasion and metastasis and may be an invasion-suppressor gene.

Acute respiratory distress syndrome in a woman with heroin and methamphetamine misuse

Methamphetamine, heroin, and cannabis are three of the most commonly misused drugs in Asia. In Taiwan, cases of misuse of methamphetamine have been increasing. In this paper, we report the case of a 23-year-old woman who had a 10-year history of smoking methamphetamine and intermittent use of heroin for 3 to 4 years. She developed pulmonary toxic effects associated with misuse of heroin and methamphetamine. She was brought to the emergency room because of consciousness disturbance and acute respiratory failure. Her symptoms of rapid progression of refractory hypoxemia, ill-defined densities over both lung fields, and normal pulmonary artery wedge pressure were consistent with acute respiratory distress syndrome. Rapid resolution of infiltrations and improvement of oxygenation were observed after mechanical ventilation with positive end-expiratory pressure support and oxygen therapy. She was discharged on the fifteenth hospital day without any sequela except for mild exertional dyspnea.

Pulmonary tuberculosis in allogeneic hematopoietic stem cell transplantation

Pulmonary tuberculosis (TB) is an endemic infectious disease in Taiwan. A retrospective study was conducted to define clinical manifestations and outcomes of patients with pulmonary TB among hematopoietic stem cell transplantation (HSCT) recipients. We identified eight out of 350 HSCT recipients as having pulmonary TB over a 6-year period. The relative risk of having pulmonary TB after HSCT was 13.1-fold higher than in the general population. There was a trend toward increased risk of having pulmonary TB in allogeneic HSCT as compared to autologous HSCT (4.8 +/- 1.8% vs 0, P = 0.067). All the eight patients with pulmonary TB received allogeneic HSCT and most (seven of eight patients) developed the infection during treatment for GVHD. Computed tomography of the chest was normal in one patient, with the rest showing either interstitial (two patients) or alveolar infiltrates (five patients) at the onset of pulmonary TB. The four fatal cases had an obviously shorter duration between HSCT and onset of infection. Our data suggest that pulmonary TB in HSCT recipients is not uncommon in this endemic area. Therefore, an effective strategy of prophylactic treatment for candidates and recipients of allogeneic HSCT, who may have latent pulmonary TB infection, must be developed.

2'-Ribose-ferrocene oligonucleotides for electronic detection of nucleic acids

We have synthesized two novel phosphoramidites with a ferrocenyl moiety at the 2'-ribose position linked through a butoxy linker. Using automated DNA/RNA synthesis techniques, oligonucleotides containing ferrocene at various positions were prepared and characterized by HPLC, MALDI-TOF mass spectrometry, and electrochemistry. Thermal stability studies of the ferrocene-modified DNA duplexes revealed that introduction of one or two ferrocenyl complexes does not result in an observed change of the T(m) values of the corresponding DNA duplexes when compared to the nonmodified hybrids. These data indicate that the introduction of a ferrocenyl group at the 2'-position of the ribose ring containing either a purine or pyrimidine base has no effect on the stability of the modified DNA. The electrochemical behavior of the ferrocene-containing DNA was examined by cyclic voltammetry. The modified 2'-ferrocene-oligonucleotides are electrochemically active and can be used as signaling probes for the electronic detection of nucleic acids on bioelectronic sensors.

Electronic detection of nucleic acids: a versatile platform for molecular diagnostics

A novel platform for the electronic detection of nucleic acids on microarrays is introduced and shown to perform well as a selective detection system for applications in molecular diagnostics. A gold electrode in a printed circuit board is coated with a self-assembled monolayer (SAM) containing DNA capture probes. Unlabeled nucleic acid targets are immobilized on the surface of the SAM through sequence-specific hybridization with the DNA capture probe. A separate signaling probe, containing ferrocene-modified nucleotides and complementary to the target in the region adjoining the capture probe binding site, is held in close proximity to the SAM in a sandwich complex. The SAM allows electron transfer between the immobilized ferrocenes and the gold, while insulating the electrode from soluble redox species, including unbound signaling probes. Here, we demonstrate sequence-specific detection of amplicons after simple dilution of the reaction product into hybridization buffer. In addition, single nucleotide polymorphism discrimination is shown. A genotyping chip for the C282Y single nucleotide polymorphism associated with hereditary hemochromatosis is used to confirm the genotype of six patients' DNA. In addition, a gene expression-monitoring chip is described that surveys five genes that are differentially regulated in the cellular apoptosis response. Finally, custom modification of individual electrodes through sequence-specific hybridization demonstrates the potential of this system for infectious disease diagnostics. The versatility of the electronic detection platform makes it suitable for multiple applications in diagnostics and pharmacogenetics.

Expression of integrins in human cultured mesothelial cells: the roles in cell-to-extracellular matrix adhesion and inhibition by RGD-containing peptide

Integrins play key roles in cell-to-cell and cell-to-extracellular matrix (ECM) adhesion. We investigated integrin expression on pleural mesothelial cells (PMCs) and the inhibitory effect of arginine-glycine-asparate (RGD)-containing peptide on the adhesion of PMCs to fibronectin and collagen. Using flow cytometry and immunostaining, PMCs freshly isolated from pleural effusions and one mesothelial cell line were screened for different integrins. Intact pleural tissue was evaluated by immunohistochemistry. The adhesion of Met-5A cells to fibronectin and collagen types I, III and IV was assayed with prior treatment of various concentrations of glycine-arginine-glycine aspartate-serine (GRGDS). On primary PMCs, alpha2, alpha3, alpha5, beta1, beta3 and alphavbeta3 were highly expressed (>70%); alpha1 expression was intermediate (30-70%); and alpha4 and alpha6 expressions were low (< 30%). On Met-SA cells, alpha3, alpha5, alpha6 and beta1 were highly expressed (>70%); alpha1 was intermediate (30-70%); and alpha2, alpha4, beta3 and alphavbeta3 were low (<30%). The patterns of immunostaining on pleural tissues were similar to the results of flow cytometry for primary PMCs except for beta3. There was no statistically different expression in various disease states (transudate vs. exudate, benign vs. malignant). The inhibitory effect of GRGDS peptide on Met-5A cell adhesion to all four matrix proteins was dose-dependent.

Structure of interfacial liquids: X-ray scattering studies

We have used synchrotron x rays to study three different liquids near solid-liquid interfaces. For either ultrathin (45-90 A) or thick ( approximately 5000 A) liquid films on silicon substrates, we find (on the basis of diffraction peaks or specular reflectivity data) that the molecules form 3-6 layers at the interface, with plane spacings close to the molecular dimensions. Rough surfaces and/or impurities reduce the density oscillation amplitudes. Making the liquid film very thin does not observably enhance the effect, which implies that layering is present even at an isolated interface (i.e., in a semi-infinite liquid). On the other hand, predeposited impurities diffuse away from the interface more easily if the liquid films are thick. The liquids studied are nonconducting, nonpolar, and nonreactive; the molecules are roughly spherical; and our substrate surface has no lateral structure. Thus our observations should apply to any liquid near a hard wall.

Vascular endothelial growth factor 189 mRNA isoform expression specifically correlates with tumor angiogenesis, patient survival, and postoperative relapse in non-small-cell lung cancer

PURPOSE

The purpose of this study was to evaluate the correlation between the expression of four different vascular endothelial growth factor (VEGF) mRNA isoforms (VEGF121, VEGF165, VEGF 189, and VEGF206) and the clinicopathologic characteristics, tumor angiogenesis, and outcome of patients with non-small-cell lung cancer.

PATIENTS AND METHODS

We examined the expression of four different VEGF mRNA isoforms in 57 non-small-cell lung cancers using reverse transcriptase polymerase chain reaction and the tumor angiogenesis using immunohistochemical staining.

RESULTS

All 57 lung cancer samples expressed the VEGF121, VEGF165, and VEGF189 mRNA isoforms, and three expressed the VEGF206 mRNA isoform. A high tumoral VEGF189 mRNA isoform expression ratio was associated with a high intratumoral microvessel count (P = .013), short survival (< 24 months; P = .001), and early postoperative relapse (< 12 months; P = .001). Survival and postoperative relapse time were significantly shorter in patients with a high compared with a low tumor VEGF189 mRNA isoform expression ratio (P = .0001 and P = .0086, respectively, log-rank test). In contrast, the VEGF165 and VEGF 206 mRNA isoform expression ratios showed no statistical correlation with tumor angiogenesis, postoperative relapse time, or survival. A high VEGF121 mRNA isoform expression ratio was associated with short survival (< 24 months) and early relapse (< 12 months). Multivariate analysis showed that VEGF 189 mRNA isoform expression, microvessel count, and nodal status were the most important independent prognostic factors for patient survival and postoperation recurrence.

CONCLUSION

The VEGF189 mRNA isoform expression ratio shows a greater correlation with tumor angiogenesis, postoperative relapse time, and survival than do the expression ratios for the VEGF121, VEGF165, and VEGF206 mRNA isoforms and can be used as a prognostic indicator for patients with non-small-cell lung cancers.

Melioidosis: an emerging infection in Taiwan?

From January 1982 to May 2000, 17 infections caused by Burkholderia pseudomallei were diagnosed in 15 patients in Taiwan; almost all the infections were diagnosed from 1994 to May 2000. Of the 15 patients, 9 (60%) had underlying diseases, and 10 (67%) had bacteremic pneumonia. Thirteen (76%) episodes of infection were considered indigenous. Four patients died of melioidosis. Seventeen B. pseudomallei isolates, recovered from eight patients from November 1996 to May 2000, were analyzed to determine their in vitro susceptibilities to 14 antimicrobial agents, cellular fatty acid and biochemical reaction profiles, and randomly amplified polymorphic DNA patterns. Eight strains (highly related isolates) were identified. All isolates were arabinose non-assimilators and were susceptible to amoxicillin-clavulanate, piperacillin-tazobactam, imipenem, and meropenem. No spread of the strain was documented.

Correlation of total VEGF mRNA and protein expression with histologic type, tumor angiogenesis, patient survival and timing of relapse in non-small-cell lung cancer

We have quantified the expression of all 4 isoforms of vascular endothelial growth factor (VEGF) mRNA in non-small-cell lung cancer (NSCLC) using a new kinetic quantitative PCR method, real-time quantitative (RTQ) RT-PCR, and investigated the association between VEGF expression at the mRNA and protein levels and the clinicopathologic variables, tumor angiogenesis, patient survival and timing of relapse. Surgical tumor specimens from 72 NCSLC patients (37 squamous-cell carcinomas, 35 adenocarcinomas) were examined. Twenty-eight patients had stage I, 10 stage II and 34 stage IIIA or IIIB disease. Total VEGF mRNA (all 4 isoforms) was quantified by RTQ RT-PCR, while VEGF protein expression and microvessel number in tumors were assessed immunohistochemically. VEGF mRNA was detected in all 72 tumor samples at significantly higher levels than in adjacent normal tissue. Tumoral VEGF mRNA levels correlated strongly with the VEGF protein staining score and microvessel count. Adenocarcinomas showed significantly higher VEGF mRNA expression and a higher protein staining score than squamous-cell carcinomas. High tumoral VEGF mRNA expression was associated with advanced (IIIA or IIIB) tumor stage, lymph node metastasis, high tumoral microvessel counts, short patient survival (<24 months) and early relapse (<12 months), while a high VEGF protein staining score was associated with high tumoral microvessel counts, short patient survival and early relapse. Patients with high tumoral levels of both VEGF mRNA and protein had significantly shorter survival and earlier relapse. In multivariate analysis, the VEGF protein staining score and nodal status were the most important independent predictors of survival and recurrence. We conclude that RTQ RT-PCR is a sensitive method for detecting and quantifying VEGF mRNA expression in NSCLC and that the expression levels of total VEGF mRNA and protein in NSCLC are strongly associated with histologic type, tumor angiogenesis, survival and timing of relapse. High VEGF expression in adenocarcinomas may contribute to their greater metastatic potential.

US-guided transthoracic cutting biopsy for peripheral thoracic lesions less than 3 cm in diameter

PURPOSE

To evaluate the safety and accuracy of ultrasonography (US)-guided transthoracic cutting biopsy for diagnosing peripheral thoracic lesions (<3 cm).

MATERIALS AND METHODS

Fifty consecutive patients with peripheral thoracic lesions less than 3 cm in diameter underwent US-guided percutaneous transthoracic cutting biopsy with a modified technique. Fifty lesions (43 parenchymal lung, two pleural, two chest wall, and three anterior mediastinal lesions) were sampled for biopsy. The final diagnosis was based on histopathologic analysis of surgical specimens (n = 18) or clinical follow-up (n = 32).

RESULTS

The histology recovery rate was 98% (49 lesions), and the correct diagnosis was obtained in 48 lesions (96%). Twenty-four (48%) lesions were malignant, and 26 (52%) were benign. The diagnostic accuracy for malignant lesions was 92% (22 of 24 lesions). A specific benign diagnosis was made in 17 (65%) of the 26 benign lesions, and the negative predictive value for malignancy was 93% (26 of 28 lesions). Only two patients (4%) developed postbiopsy pneumothorax, and three (6%) developed postbiopsy hemoptysis. Biopsy helped prevent surgery or thoracoscopy in 32 patients (64%): 18 patients with benign disease and 14 with multiple metastases or inoperable cancer.

CONCLUSION

US-guided transthoracic cutting biopsy appears to be a safe and effective method for diagnosing peripheral thoracic lesions less than 3 cm in diameter. The high diagnostic accuracy for benign lesions and metastatic lung cancer can help prevent surgery in many cases.

Correlation of total VEGF mRNA and protein expression with histologic type, tumor angiogenesis, patient survival and timing of relapse in non-small-cell lung cancer

We have quantified the expression of all 4 isoforms of vascular endothelial growth factor (VEGF) mRNA in non-small-cell lung cancer (NSCLC) using a new kinetic quantitative PCR method, real-time quantitative (RTQ) RT-PCR, and investigated the association between VEGF expression at the mRNA and protein levels and the clinicopathologic variables, tumor angiogenesis, patient survival and timing of relapse. Surgical tumor specimens from 72 NCSLC patients (37 squamous-cell carcinomas, 35 adenocarcinomas) were examined. Twenty-eight patients had stage I, 10 stage II and 34 stage IIIA or IIIB disease. Total VEGF mRNA (all 4 isoforms) was quantified by RTQ RT-PCR, while VEGF protein expression and microvessel number in tumors were assessed immunohistochemically. VEGF mRNA was detected in all 72 tumor samples at significantly higher levels than in adjacent normal tissue. Tumoral VEGF mRNA levels correlated strongly with the VEGF protein staining score and microvessel count. Adenocarcinomas showed significantly higher VEGF mRNA expression and a higher protein staining score than squamous-cell carcinomas. High tumoral VEGF mRNA expression was associated with advanced (IIIA or IIIB) tumor stage, lymph node metastasis, high tumoral microvessel counts, short patient survival (<24 months) and early relapse (<12 months), while a high VEGF protein staining score was associated with high tumoral microvessel counts, short patient survival and early relapse. Patients with high tumoral levels of both VEGF mRNA and protein had significantly shorter survival and earlier relapse. In multivariate analysis, the VEGF protein staining score and nodal status were the most important independent predictors of survival and recurrence. We conclude that RTQ RT-PCR is a sensitive method for detecting and quantifying VEGF mRNA expression in NSCLC and that the expression levels of total VEGF mRNA and protein in NSCLC are strongly associated with histologic type, tumor angiogenesis, survival and timing of relapse. High VEGF expression in adenocarcinomas may contribute to their greater metastatic potential.

Quantification of VEGF mRNA expression in non-small cell lung cancer using a real-time quantitative reverse transcription-PCR assay and a comparison with quantitative competitive reverse transcription-PCR

A reliable quantitative method for measuring gene product expression is important in investigating the relationship between growth factors and tumor biological behavior. In this study, we quantified the expression of vascular endothelial growth factor (VEGF) mRNA in 104 paired samples of lung cancer tissue and the surrounding nontumorous lung tissue using a new kinetic quantitative polymerase chain reaction (PCR) method, ie, real-time quantitative reverse transcription-PCR (RTQ RT-PCR). The samples consisted of 46 squamous cell carcinomas, 50 adenocarcinomas, and 8 undifferentiated cell carcinomas. In 17 cases, the results obtained were compared with those obtained using quantitative competitive RT-PCR (QC RT-PCR). Using RTQ RT-PCR, VEGF mRNA expression was detected and quantified in all 104 (100%) lung cancer samples and their normal counterparts. VEGF mRNA expression in the lung cancer tissue was significantly higher than in the normal counterparts (95% CI: 0.575 approximately 1.727, p < 0.001; paired t test). In 68 (65.4%) cases, VEGF mRNA expression was higher in the cancer tissue than normal tissue. VEGF mRNA expression was higher in nonsquamous cell carcinoma (p = 0.02), and higher in tumor with hilar or mediastinal lymph node metastasis (p = 0.024). QC RT-PCR was able to detect and quantify VEGF mRNA expression in 15/17 (88%) lung cancer samples and 12/17 (70.6%) normal tissue samples. The values for VEGF mRNA expression were higher in the tumor in 13 (76%) cases. Comparison of the values of the VEGF mRNA expression quantified using RTQ RT-PCR or QC RT-PCR showed a good correlation between results obtained using these two methods, both in cancer tissue (r = 0.68, p = 0.0025) and normal counterpart (r = 0.53, p = 0.027). Agreement between the results for the relative expression of VEGF mRNA expression in cancer and normal tissue obtained using these two methods was seen in 14/16 cases (88%). We conclude that RTQ RT-PCR is as accurate as QC RT-PCR and is more sensitive than QC RT-PCR in detecting and quantifying VEGF mRNA expression in lung cancer and normal tissues, and both methods reveal that the VEGF mRNA expression is higher in lung cancer tissue than in healthy lung tissue.

Interleukin-8 messenger ribonucleic acid expression correlates with tumor progression, tumor angiogenesis, patient survival, and timing of relapse in non-small-cell lung cancer

Tumor-associated angiogenesis is important for tumor growth and metastasis. Interleukin (IL)-8 was recently reported to be an important angiogenic factor both in vitro and in vivo. In this study we evaluated, for the first time, IL-8 messenger RNA (mRNA) expression in non-small-cell lung cancer (NSCLC), using real-time quantitative reverse-transcription-polymerase chain reaction, and correlated IL-8 mRNA expression in tumor and nontumor lung samples from 58 patients with NSCLC (29 with squamous cell carcinoma and 29 with adenocarcinoma, of whom 20 had Stage I, 10 had Stage II, and 28 had Stage III disease) with these patients' clinicopathologic characteristics, angiogenesis, and outcome. IL-8 protein expression and tumor microvessel count (MC) were assessed immunohistochemically. IL-8 mRNA expression was significantly greater in tumor tissue; high expression was highly associated with tumor in advanced stages (p = 0.03), distant lymph node metastasis (p = 0.02), high tumor MC (> 123) (p = 0.00003), short survival (< 26 mo) (p < 0.00001), and early relapse (< 16 mo) (p < 0.00001). Tumor MC correlated strongly with IL-8 mRNA expression (r = 0.56, p < 0.001). Multivariate analysis showed IL-8 mRNA expression and intratumor MC to be the most important predictors of patient survival and relapse. Thus, in NSCLC, IL-8 mRNA expression is strongly associated with tumor progression, tumor angiogenesis, survival, and time to relapse, suggesting its use as a prognostic indicator.

Clinical spectrum of acute respiratory distress syndrome in a tertiary referral hospital: etiology, severity, clinical course, and hospital outcome

BACKGROUND AND PURPOSE

The clinical picture of patients with acute respiratory distress syndrome (ARDS) in Taiwan has seldom been reported, although new definitions of ARDS have been introduced over the past years. The purpose of this study was to investigate the clinical characteristics, modalities of management, and outcomes in patients with ARDS treated in a tertiary referral hospital.

METHODS

Case records were selected through a computerized search of diagnosis codified at discharge during the period from January 1995 to June 1997. Patients who met the criteria of the American-European Consensus Conference definition of ARDS were included and their medical records were retrospectively reviewed.

RESULTS

A total of 145 patients (91 men, 54 women; mean age, 58 years) who fulfilled the criteria for ARDS were identified. Malignancy (n = 53) and diabetes mellitus (n = 23) were the most common co-morbid conditions. Pneumonia (n = 90), including community-acquired pneumonia in 45 (31%) patients, was the most common risk factor. The lung injury score at the time of ARDS diagnosis was 2.89 +/- 0.40 (mean +/- standard error, SE). The worst value of PaO2/FIO2 was 86.8 +/- 3.8 mm Hg (mean +/- SE). Among the 145 patients, 130 (90%) received mechanical ventilation and 118 (81%) were treated in the intensive care unit. In-hospital mortality was 87%. Seventy (48%) patients received intensive treatment for ARDS, among whom 52 (74%) died; the most common causes of death were multiple organ failure (54%) and respiratory failure (23%).

CONCLUSIONS

The mortality in patients with ARDS was high in this tertiary referral institution. Our findings suggest that aggressive ventilatory, pharmacologic, and supportive therapy may be important to achieve a higher survival rate.