[A multicenter epidemiological study of acute bacterial meningitis in children].

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum ß-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ2=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.

[Risk factors and resistance patterns of invasive Acinetobacter Baumannii infection in Children].

Objective: To understand the risk factors and antibiotics-resistant patterns of invasive Acinetobacter baumannii infection in Children. Methods: This retrospective study was conducted in 6 tertiary hospitals from January 2016 to December 2018. The basic information, clinical data and the results of antimicrobial susceptibility testing were collected from the 98 pediatric inpatients with Acinetobacter baumannii isolated from blood or cerebrospinal fluid and analyzed. According to the susceptibility of the infected strains to carbapenems, they were divided into carbapenem-sensitive Acinetobacter baumannii (CSAB) group and carbapenem-resistant Acinetobacter baumannii (CRAB) group. According to the possible sources of infection, they were divided into nosocomial infection group and community infection group. Chi-square test or Fisher exact test were used to analyze categorical variables and rank sum test were used to analyze continuous variables. The risk factors of invasive CRAB infection in children were analyzed by Logistic regression. Result: There were 56 males and 42 females in 98 cases. The onset age of patients was 8 (2, 24) months. There were 62 cases (63%) from rural area. A total of 87 cases (89%) were confirmed with bloodstream infection, and 12 cases (12%) confirmed with meningitis (1 case was accompanied with bloodstream infection). In these patients, 66 cases (67%) received invasive medical procedures or surgery, 54 cases (55%) received carbapenems-containing therapy. Twenty-four cases were infected with CRAB, and 74 cases with CSAB. The onset age of cases in CRAB group was lower than that in CSAB group (4 (1, 9) vs. 10 (4, 24) months, Z=-2.16, P=0.031). The proportions of hospitalization in intensive care unit, carbapenem antibiotics using, pneumonia and adverse prognosis in CRAB group were higher than those in CSAB group (6 cases (25%) vs. 4 cases (5%), 18 cases (75%) vs. 36 cases (49%), 17 cases (71%) vs. 17 cases (23%), 6 cases (25%) vs. 4 cases (5%), χ2=5.61, 5.09, 18.32, 5.61, all P<0.05). Seventy-seven cases were nosocomial infection and 21 cases were hospital-acquired infection. The proportion of children hospitalized in high-risk wards for nosocomial infections, length of hospitalization, number of antimicrobial therapy received and duration of antimicrobial therapy were higher in the hospital associated infection group than those in the community acquired infection group (all P<0.05). Logistic regression analysis showed that children from rural area (OR=8.42, 95%CI 1.45-48.88), prior mechanical ventilation (OR=12.62, 95%CI 1.31-121.76), and prior antibiotic therapy (OR=4.90, 95%CI 1.35-17.72) were independent risk factors for CRAB infection. The resistance percentage of CSAB isolates to many classes of antibiotics was <6% except to gentamicin, which was as high as 20% (13/65). All CRAB isolates of resistant to ampicillin-sulbactam (20/20), cefepime (23/23), piperacillin (17/17), meropenem (23/23) and imipenem (24/24) were 100%. The resistance percentage to other antibiotics were up to 42%-96%. Conclusions: Most of invasive Acinetobacter baumannii infection in children in China are hospital-acquired. The outcome of invasive CRAB infection was poorer than that of CSAB infection. The drug resistance rate of CRAB strains isolated is high. Living in rural area, prior invasive mechanical ventilation and prior antibiotic therapy were independent risk factors for invasive CRAB infection. The prevention and control of nosocomial infection and appropriate use of antibiotics to reduce Acinetobacter baumannii infection.

Development of a narrow stopband filter for spectroscopic fast ion deuterium-alpha measurements.

A new technique to attenuate the unshifted deuterium Balmer-alpha (D-alpha) emission is developed and tested for the fast ion D-alpha (FIDA) diagnostic. The unshifted D-alpha emission, at λ = 656.1 nm, is around three orders of magnitude higher than the desired FIDA emission. Blocking the strong emission feature is essential to prevent blooming and light smearing on the CCD chip and scattered light contamination. The new method is a notch filter approach that utilizes the reflection from ultra-narrow bandpass filters to block the saturating signal before it enters the spectrometer. Collimated light from the fibers is reflected off the filter at a 15° angle of incidence. Measurements show that a center wavelength transmission of 0.006 and a blocking full width at half maximum of ∼1 nm are achieved by using a 200 µm fiber and a 20 mm focal length collimator with two filters.

Trends and publication rates of abstracts presented at the British Association of Head and Neck Oncologists' (BAHNO) annual meetings: 2009 - 2015.

The British Association of Head and Neck Oncologists (BAHNO) hosts an annual meeting at which research from all specialties involved in the management of head and neck oncology is presented. We have analysed the rate of publication of the abstracts presented, and reviewed the finalised programmes from the meetings between 2009 and 2015. The 2014 meeting was excluded as it was a combined international meeting. Key terms were searched in PubMed and Google Scholar to identify publications in peer-reviewed journals. If none was identified, these platforms were searched for the authors' names. Published abstracts were excluded. Study and journal demographic data were extracted. A total of 363 abstracts were presented, including 75 oral, 271 poster, and 17 of unclear presentation method. The total publication rate was 31.1%, representing 46.7% of oral abstracts and 27.3% of poster presentations. The mean time to publication was 16.5 months. Research was published in 45 individual journals with a mean (range) impact factor of 2.559 (0.886-36.418). There was a trend towards an increasing number of presentations over time with a decreasing publication rate. However, there was no trend in mean impact factor by year. The publication rate of abstracts presented at the BAHNO annual meetings is comparable with that of other large otolaryngology and head and neck conferences. The mean impact factor has not previously been utilised within this field, but may prove a useful metric that enables monitoring of the quality of presented research and comparison of the impact of the conferences.

Treatment outcomes of laryngectomy compared to non-surgical management of T3 laryngeal carcinomas: a 10-year multicentre audit of 179 patients in the northeast of England.

OBJECTIVE: Wide-ranging outcomes have been reported for surgical and non-surgical management of T3 laryngeal carcinomas. This study compared the outcomes of T3 tumours treated with laryngectomy or (chemo)radiotherapy in the northeast of England. METHODS: The outcomes of T3 laryngeal carcinoma treatment at three centres (2007-2016) were retrospectively analysed using descriptive statistics and survival curves. RESULTS: Of 179 T3 laryngeal carcinomas, 68 were treated with laryngectomies, 57 with chemoradiotherapy and 32 with radiotherapy. There was no significant five-year survival difference between treatment with laryngectomy (34.1 per cent) and chemoradiotherapy (48.6 per cent) (p = 0.184). The five-year overall survival rate for radiotherapy (12.5 per cent) was significantly inferior compared to laryngectomy and chemoradiotherapy (p = 0.003 and p < 0.001, respectively). The recurrence rates were 22.1 per cent for laryngectomy, 17.5 per cent for chemoradiotherapy and 50 per cent for radiotherapy. There were significant differences in recurrence rates when laryngectomy (p = 0.005) and chemoradiotherapy (p = 0.001) were compared to radiotherapy. CONCLUSION: Laryngectomy and chemoradiotherapy had significantly higher five-year overall survival and lower recurrence rates compared with radiotherapy alone. Laryngectomy should be considered in patients unsuitable for chemotherapy, as it may convey a significant survival advantage over radiotherapy alone.

Prognostic impact of prognostic nutritional index in advanced (stage IIIB/IV) non-small cell lung cancer patients.

Prognostic nutritional index (PNI) is a parameter reflecting prognosis for various cancers, including resected lung cancer. However, there were few reports to study the relationship between the PNI and overall survival (OS) in patients with advanced (stage IIIB/IV) non-small lung cancer (NSCLC). In this study, we collected the clinical data of 315 patients with advanced (stage IIIB/IV) NSCLC who had received chemotherapy or epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) between January 2010 and June 2011. Survival curves were plotted using the Kaplan-Meier method. Multivariate analyses were used to evaluate prognostic significance of PNI in patients with advanced (stage IIIB/IV) NSCLC. In our analysis, we found that PNI (p=0.001) was significantly associated with OS in patients with advanced (stage IIIB/IV) NSCLC, so was smoking (p<0.001) and disease stage (p=0.005). We demonstrated that PNI could be utilized to predict survival outcomes in patients with advanced (stage IIIB/IV) NSCLC. Patients with a lower PNI may have worse prognosis.

Dose dependency PM2.5 aggravated airway inflammation in asthmatic mice via down-regulating expression of ITGB4.

OBJECTIVE: We aimed to investigate whether PM2.5 has the potential to exacerbate neutrophil airway inflammation and to analyze the underlying mechanisms. MATERIALS AND METHODS: The high-volume air sampler (Laoying 2033B, Qingdao, China) was used to collect PM2.5 from January 01, 2016 to December 21, 2016 in Yantai, Shandong Province, China. BALB/c mice were divided into the following four groups: control group, ovalbumin (OVA) group, low-dose PM2.5 group and high-dose PM2.5 group. Mice except for control group were sensitized and challenged by OVA, and those in low-dose PM2.5 group and high-dose PM2.5 group were intranasally administered by PM2.5 suspension. Airway responsiveness of mice was measured. Enzyme-linked immunosorbent assay (ELISA) kit was used to evaluate the expressions of interleukin 17 (IL-17) and tumor necrosis factor-α (TNF-α) in bronchoalveolar lavage fluid (BALF) and serum samples. Cell counting in BALF and histological examination were measured to explore PM2.5-induced airway inflammation. Protein expression of Integrin ß4 (ITGB4) was assessed by Western blot. RESULTS: Airway hyperresponsiveness (AHR) exacerbated in PM2.5 exposed asthmatic mice in progressively increased doses of acetylcholine chloride (ACH). Levels of IL-17 and TNF-αin BALF and serum increased significantly in PM2.5 groups compared with other groups with significant differences between two PM2.5 groups. PM2.5 exposure exacerbated inflammatory cell infiltration and mucus secretion in airways of asthmatic mice. Percentage of neutrophils in PM2.5 groups was significantly higher in dose-dependent manner. OVA and PM2.5 co-exposure inhibited the expression of ITGB4. In particular, ITGB4 expression in mice of high-dose PM2.5 group was significantly lowered than the low-dose PM2.5 group. CONCLUSIONS: We showed that PM2.5 exposure exacerbates neutrophil airway inflammation in asthmatic mice though up-regulating expressions of IL-17 and TNF-α but down-regulating the expression of ITGB4.

Single-stage helical rim reconstruction using a post-auricular bipedicled flap.

BACKGROUND: Middle-third helical rim defects may arise from trauma or oncological resection, and pose a challenging reconstructive problem. Reconstructing defects larger than 2 cm using traditional methods commits patients to the inconvenience of staged procedures. METHOD: This paper describes a single-stage helical rim reconstruction technique using a post-auricular bipedicled flap and ipsilateral conchal cartilage graft for delayed middle-third helical rim reconstruction. RESULTS: Two examples of this technique used in post-trauma and oncological reconstruction cases are presented, with pre- and post-operative photographs provided for demonstration. CONCLUSION: Contralateral graft harvest and staged operations for helical rim reconstruction are associated with donor site morbidity and the inconvenience of multiple operations to achieve the desired reconstructive outcome. Our single-stage helical rim reconstruction technique was well tolerated by patients, and showed satisfactory aesthetic results in terms of size and symmetry.

[Clinical analysis of the risk factors for No.12p LN metastasis in advanced gastric cancer].

Objective: To analyse the risk factors for periportal lymphnode (No.12p LN) in advanced gastric cancer. Methods: A retrospective analysis of 183 patients with advanced gastric cancer from January 2005 to December 2010, and all patients were underwent D2 lymphadenectomy in addition to No. 12p LN dissections. Potential clinicopathological factors that could influence No. 12p LN metastasis were statistically analyzed. Results: There were 18 cases (9.8%) with periportal lymphnode metastasis. A logistic regression analysis suggested that the Borrmann type (Ⅲ/Ⅳ versus Ⅰ/Ⅱ, P=0.008), tumor size (≥6 cm vs <6 cm, P=0.001), and depth of invasion (pT4 vs pT2/pT3, P=0.049) were associated with 9.5-, 8.5-, and 3.2-fold increases, respectively, for risk of No. 12p LN metastasis. A logistic regression analysis also showed that No. 5 (P=0.002) and No. 12a (P=0.002) LN metastasis were associated with 7.5- and 7.3-fold increases, respectively, for risk of No. 12p LN metastasis. In addition, significant differences in 5-year survival of patients with and without No. 12p LN metastasis were observed (11.1% vs 32.7%, P=0.042). Conclusions: Borrmann type, tumor size and depth of invasion are significant factors for identifying patients with No. 12p LN metastasis. Patients with No. 5 or No. 12a LN metastasis should be higher possibility of No.12p LN metastasis.

microRNA-142-3p inhibits apoptosis and inflammation induced by bleomycin through down-regulation of Cox-2 in MLE-12 cells.

microRNA (miR)-142-3p is implicated in malignancy and has been identified as a biomarker for aggressive and recurrent lung adenocarcinomas. This study aimed to evaluate the inhibitory effect of miR-142-3p on apoptosis and inflammation induced by bleomycin in MLE-12 cells. MLE-12 cells were first transfected either with miR-142-3p mimic or miR-142-3p inhibitor and then the cells were exposed to 50 µg/mL of bleomycin. Thereafter, cell viability, apoptosis and the expression of pro-inflammatory cytokines were assessed using CCK-8, flow cytometry, RT-PCR and western blot analyses. Cox-2, PI3K, AKT and mTOR expressions were detected by western blotting after bleomycin was administered together with NS-398 (an inhibitor of Cox-2). As a result, cell viability was significantly decreased, as well as apoptosis and the expression of IL-1 and TNF-α were remarkably increased after 50 and 100 µg/mL of bleomycin administration. miR-142-3p overexpression alleviated bleomycin-induced apoptosis and overproduction of these two pro-inflammatory cytokines, while miR-142-3p suppression exhibited completely opposite results. Up-regulation of Cox-2 and inactivation of PI3K/AKT/mTOR were found in bleomycin-pretreated cells, while these abnormal regulations were partially abolished by miR-142-3p overexpression and NS-398. In conclusion, this study demonstrated that miR-142-3p overexpression protected bleomycin-induced injury in lung epithelial MLE-12 cells, possibly via regulating Cox-2 expression and PI3K/AKT/mTOR signaling pathway. These findings provide evidence that miR-142-3p may be a therapeutic strategy for idiopathic pulmonary fibrosis (IPF) treatment.

microRNA-142-3p inhibits apoptosis and inflammation induced by bleomycin through down-regulation of Cox-2 in MLE-12 cells

microRNA (miR)-142-3p is implicated in malignancy and has been identified as a biomarker for aggressive and recurrent lung adenocarcinomas. This study aimed to evaluate the inhibitory effect of miR-142-3p on apoptosis and inflammation induced by bleomycin in MLE-12 cells. MLE-12 cells were first transfected either with miR-142-3p mimic or miR-142-3p inhibitor and then the cells were exposed to 50 μg/mL of bleomycin. Thereafter, cell viability, apoptosis and the expression of pro-inflammatory cytokines were assessed using CCK-8, flow cytometry, RT-PCR and western blot analyses. Cox-2, PI3K, AKT and mTOR expressions were detected by western blotting after bleomycin was administered together with NS-398 (an inhibitor of Cox-2). As a result, cell viability was significantly decreased, as well as apoptosis and the expression of IL-1 and TNF-α were remarkably increased after 50 and 100 μg/mL of bleomycin administration. miR-142-3p overexpression alleviated bleomycin-induced apoptosis and overproduction of these two pro-inflammatory cytokines, while miR-142-3p suppression exhibited completely opposite results. Up-regulation of Cox-2 and inactivation of PI3K/AKT/mTOR were found in bleomycin-pretreated cells, while these abnormal regulations were partially abolished by miR-142-3p overexpression and NS-398. In conclusion, this study demonstrated that miR-142-3p overexpression protected bleomycin-induced injury in lung epithelial MLE-12 cells, possibly via regulating Cox-2 expression and PI3K/AKT/mTOR signaling pathway. These findings provide evidence that miR-142-3p may be a therapeutic strategy for idiopathic pulmonary fibrosis (IPF) treatment.

[Risk factors for pulmonary fibrosis in patients with paraquat poisoning].

Objective: To investigate the risk factors for pulmonary fibrosis in patients with paraquat (PQ) poisoning. Methods: A total of 120 patients with PQ poisoning who were admitted from January 2012 to December 2014 were enrolled. According to the presence or absence of pulmonary fibrosis, the patients were divided into non-pulmonary fibrosis group (67 patients) and pulmonary fibrosis group (53 patients) . The Acute Physiology and Chronic Health Evaluation II (APACHE II) score was obtained on days 1 and 3 of poisoning. Routine blood test results, blood biochemical parameters, and radiological parameters were recorded, and the patients with PQ poisoning were followed up for survival and pulmonary fibrosis. Results: A total of 39 patients with PQ poisoning died, resulting in a mortality rate of 32.5%. There were 53 patients who developed pulmonary interstitial fibrosis, yielding an incidence rate of 44.2%. Compared with the non-pulmonary fibrosis group, the pulmonary fibrosis group had a significantly higher age, a significantly higher dose of PQ, and significantly higher APACHE II scores on days 1 and 3 of poisoning (P<0.01) , as well as significantly higher white blood cell (WBC) count and neutrophil count on day 1, significantly higher levels of urea nitrogen, creatinine, and blood glucose on days 1 and 3, and significantly higher activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) (P<0.01) . The logistic regression analysis showed that the dose of PQ, WBC count and neutrophil count on day 1, APACHE II scores on days 1 and 3 of poisoning, levels of urea nitrogen, creatinine, and blood glucose, and activities of AST and ALT were associated with the development of pulmonary fibrosis in patients with PQ poisoning. Conclusion: Oral dose of PQ, APACHE II scores on days 1 and 3 of poisoning, levels of urea nitrogen, creatinine, and blood glucose, activities of AST and ALT, and WBC count and neutrophil count on day 1 are risk factors for pulmonary fibrosis in patients with paraquat poisoning.

Effect of gadobutrol on VX2 magnetic resonance diffusion-weighted imaging.

The aim of this study was to evaluate the effect of contrast agent gadobutrol on the magnetic resonance diffusion-weighted imaging (MR DWI). Gadobutrol has higher relaxivity than Gd-DTPA and it also has higher formulation 1.0 M than Gd-DTPA 0.5 M. VX2 tumor implanted on the left thigh of each New Zealand rabbit was used as the animal model. The MR scanning was performed using a 1.5 T clinical whole-body MR scanner with an 8-channel knee coil. The results showed that there were significant differences in the signal-to-noise ratio (SNR) and apparent diffusion coefficient (ADC) values between tumor and muscle both before and after gadobutrol injection (0.1 mmol/kg). However, there were no significant differences in the SNR and ADC values of tumor or muscle before and after gadobutol administration. There were also no significant difference in the contrast-to-noise ratio (CNR) values of tumor and muscle before and after gadobutrol injection.

Oridonin-induced apoptosis in leukemia K562 cells and its mechanism.

Oridonin, an extract from the Chinese herb Rabdosia rubescens, is currently one of the most important traditional Chinese herbal medicines. Recently oridonin has been reported to have anti- tumor effects in a large variety of malignant diseases. In this study, we investigated the apoptotic inducing effect of oridonin in leukemia K562 cells and its mechanism. Cell growth inhibition was measured using a microculture tetrazolium assay, apoptosis was measured by flow cytometry and electron microscopy as well as by DNA fragmentation analysis. Telomerase activity was measured by TRAP-enzyme- linked immunosorbent assay, and the expression of Bcl-2 and Bax proteins was detected by western blot analysis. The results showed that oridonin could inhibit the proliferation and induce apoptosis on leukemia K562 cells remarkably. Telomerase activity as well as Bcl-2 expression was down- regulated, while Bax expression was up-regulated concurrently, when apoptosis ocurred. We therefore conclude that oridonin demonstrated anti-proliferative and apoptosis-inducing effects on K562 cells in vitro, and that changes in bcl-2 and bax protein levels as well as telomerase activity may play an important role in its mechanism of action.

Expression of survivin and bax/bcl-2 in peroxisome proliferator activated receptor-gamma ligands induces apoptosis on human myeloid leukemia cells in vitro.

The present study was undertaken to investigate the mechanisms of peroxisome proliferator activated receptor-gamma (PPAR-gamma) ligand-induced apoptosis on human myeloid leukemia K562 and HL-60 cell lines. The results revealed that both 15-deoxy-delta(12,14)-prostaglandin J2 (15d-PGJ2) and troglitazone (TGZ) have significant anti-proliferation- and apoptosis-inducing effects on these two kinds of leukemia cells. Marked morphological changes of cell apoptosis including condensation of chromatin and nuclear fragmentation were observed clearly using Wright's and Hoechst 33258 staining. Reverse transcription-PCR and western blot analyses demonstrated that both survivin and bcl-2 expression were downregulated markedly, while bax expression was upregulated concurrently when apoptosis occurred. We therefore conclude that 15d-PGJ2 and TGZ have significant apoptosis effects on K562 and HL-60 cells in vitro, and that upregulation of bax as well as downregulation of survivin and bcl-2 expression may be the important apoptosis-inducing mechanisms. The results suggest that PPAR-gamma ligands may serve as potential therapeutic agents for both acute and chronic myeloid leukemia.

Anti-proliferative effects of oridonin on SPC-A-1 cells and its mechanism of action.

Oridonin, an extract from the Chinese herb Rabdosia rubescens, is currently one of the most important traditional Chinese herbal medicines. We investigated the anti-proliferative effect of oridonin on the lung cancer cell line SPC-A-1 and its mechanism of action. Growth inhibition was measured using a microculture tetrazolium assay and apoptosis was measured by several standard methods. Western blot analysis measured the expression of bcl-2 and bax proteins. Oridonin (> 28 micromol/l) inhibited the growth of SPC-A-1 cells and induced apoptosis. Marked morphological changes indicative of apoptosis were observed, especially in cells treated with oridonin for 48 - 60 h. Western blot analysis revealed downregulation of bcl-2 and upregulation of bax proteins following treatment with oridonin for 48 h. We conclude that oridonin demonstrated anti-proliferative and apoptosis-inducing effects on SPC-A-1 cells in vitro, and that changes in bcl-2 and bax protein levels may play an important role in its mechanism of action.

Effect of chromium content on structure and mechanical properties of Ti-7.5Mo-xCr alloys.

The present work is a study of a series of Ti-7.5Mo-xCr alloys with the focus on the effect of chromium content on the structure and mechanical properties of the alloys. Experimental results show that low hardness, strength and modulus binary Ti-7.5Mo alloy is comprised primarily of fine, acicular martensitic alpha' phase. When 1 wt % Cr is added, a small amount of beta phase is retained. With 2 wt % or more chromium added, the entire alloy becomes equi-axed beta phase with bcc crystal structure. The average beta grain size decreases with Cr content. When the alloy contains about 2-4 wt % Cr, a metastable omega phase is present. In Ti-7.5Mo-2Cr alloy appears the highest omega intensity accompanied with high microhardness, bending strength and modulus. The omega-induced embrittling effect is most profound in Ti-7.5Mo-2Cr alloy that exhibits a terrace type fracture surface covered with numerous micron-sized dimples. The alloys with higher Cr contents show normal ductile type fractography with much larger deformation dimples. The present results indicate that Ti-7.5Mo-(4-6)Cr alloys seem to be potential candidates for implant application.

Nonlinear bio-photonic crystal effects revealed with multimodal nonlinear microscopy.

Highly optically active nonlinear bio-photonic crystalline and semicrystalline structures in living cells were studied by a novel multimodal nonlinear microscopy. Numerous biological structures, including stacked membranes and aligned protein structures are highly organized on a nanoscale and have been found to exhibit strong optical activities through second-harmonic generation (SHG) interactions, behaving similarly to man-made nonlinear photonic crystals. The microscopic technology used in this study is based on a combination of different imaging modes including SHG, third-harmonic generation, and multiphoton-induced fluorescence. With no energy release during harmonic generation processes, the nonlinear-photonic-crystal-like SHG activity is useful for investigating the dynamics of structure-function relationships at subcellular levels and is ideal for studying living cells, as minimal or no preparation is required.