Graphene based widely-tunable and singly-polarized pulse generation with random fiber lasers

Pulse generation often requires a stabilized cavity and its corresponding mode structure for initial phase-locking. Contrastingly, modeless cavity-free random lasers provide new possibilities for high quantum efficiency lasing that could potentially be widely tunable spectrally and temporally. Pulse generation in random lasers, however, has remained elusive since the discovery of modeless gain lasing. Here we report coherent pulse generation with modeless random lasers based on the unique polarization selectivity and broadband saturable absorption of monolayer graphene. Simultaneous temporal compression of cavity-free pulses are observed with such a polarization modulation, along with a broadly-tunable pulsewidth across two orders of magnitude down to 900 ps, a broadly-tunable repetition rate across three orders of magnitude up to 3 MHz, and a singly-polarized pulse train at 41 dB extinction ratio, about an order of magnitude larger than conventional pulsed fiber lasers. Moreover, our graphene-based pulse formation also demonstrates robust pulse-to-pulse stability and wide-wavelength operation due to the cavity-less feature. Such a graphene-based architecture not only provides a tunable pulsed random laser for fiber-optic sensing, speckle-free imaging, and laser-material processing, but also a new way for the non-random CW fiber lasers to generate widely tunable and singly-polarized pulses.

Cemented allograft-prosthesis composite reconstruction for the proximal femur tumor

INTRODUCTION

Cemented allograft-prosthesis composite (APC) reconstruction is one option following resection of the proximal femur tumor. However, rare studies have focused on the indications and complications. The goal of the present study was to (1) ascertain the indications for cemented APC arthroplasty in the proximal femur; (2) identify the detailed perioperative management; and (3) illustrate our experiences to avoid the complications of cemented APC.

MATERIALS AND METHODS

A total 28 patients who underwent cemented APC reconstruction of the proximal femur after tumor resection were retrospectively evaluated at a median follow-up of 56 months. Clinical records and radiographs were reviewed to evaluate patients' outcome.

RESULTS

In our series, excluding three cases of death that had a short follow-up period, union occurred in 22 (88.0%) patients (range 9-18 months). Nonunion of the greater trochanter was seen in six of the 12 patients (50.0%). Eight (32.0%) hips had resorption. There were two (8.0%) hips that were observed to have asymptomatic wear of the acetabulum. The average Musculoskeletal Tumor Society (MSTS) score was 26.5 points. The average Harris Hip Score (HHS) score was 80.6 points. There were no cases of recurrence, but metastasis was found in two hips.

CONCLUSIONS

Mastering indications, perioperative management, and complication prevention are all very important in the APC reconstruction after resection of the proximal femur.

All optical mode controllable Er-doped random fiber laser with distributed Bragg gratings

An all-optical method to control the lasing modes of Er-doped random fiber lasers (RFLs) is proposed and demonstrated. In the RFL, an Er-doped fiber (EDF) recoded with randomly separated fiber Bragg gratings (FBG) is used as the gain medium and randomly distributed reflectors, as well as the controllable element. By combining random feedback of the FBG array and Fresnel feedback of a cleaved fiber end, multi-mode coherent random lasing is obtained with a threshold of 14 mW and power efficiency of 14.4%. Moreover, a laterally-injected control light is used to induce local gain perturbation, providing additional gain for certain random resonance modes. As a result, active mode selection of the RFL is realized by changing locations of the laser cavity that is exposed to the control light.

Stark effect induced microcavity polariton solitons

This paper proposes a way of generating polariton solitons (PSs) in a semiconductor microcavity using Stark effect as the trigger mechanism. A Stark pulse performing as the writing beam is used to excite non-resonant fluctuations of polariton, which finally evolves into bright PSs. It is found that a branch of PS solutions versus pump parameters could be found through optimizing parameters of the Stark pulse, and polarization of the generated PS is dependent on the writing beam.

Effects of ultrasound combined with ozone on the degradation of organophosphorus pesticide residues on lettuce

Methamidophos (MDP) and dichlorvos (DDVP) are organophosphorous pesticides which are commonly used for pest control in agriculture to obtain better yields.

Graphene enhanced evanescent field in microfiber multimode interferometer for highly sensitive gas sensing

Graphene based new physics phenomena are leading to a variety of stimulating graphene-based photonic devices. In this study, the enhancement of surface evanescent field by graphene cylindrical cladding is observed, for the first time, by using a graphene-coated microfiber multi-mode interferometer (GMMI). It is found theoretically and experimentally that the light transmitting in the fiber core is efficiently dragged by the graphene, hence significantly enhancing the evanescent fields, and subsequently improving the sensitivity of the hybrid waveguide. The experimental results for gas sensing verified the theoretical prediction, and ultra-high sensitivities of ~0.1 ppm for NH(3) gas detection and ~0.2 ppm for H(2)O vapor detection are achieved, which could be used for trace analysis. The enhancement of surface evanescent field induced by graphene may pave a new way for developing novel graphene-based all-fiber devices with compactness, low cost, and temperature immunity.

Relationship between the angle of vertebral screws and spinal lateral angulation after fixation of thoracolumbar fractures via an anterior approach

This study investigated possible contributors to lateral spinal angulation after surgical fixation of thoracolumbar fractures via an anterior approach. We retrospectively examined lateral angulation in 172 cases of thoracolumbar fractures treated in this manner. The coronal Cobb angle and angles of the screws relative to the endplates were determined from radiographs. The patients completed the Short Form 36, Oswestry Disability Index, Japanese Orthopaedic Association Back Pain Evaluation Questionnaire, and Visual Analogue Scale at the final follow-up visit. The mean coronal Cobb angle was 0.75° ± 3.91° (-14.25° to 14.55°) preoperatively, 3.17° ± 4.07° (-8.18° to 14.01°) immediately postoperatively, and 3.46° ± 4.21° (-1.05° to 17.27°) at the final follow-up visit. The superior posterior and inferior anterior screws were more parallel to their respective endplates when the approach was made ≥2 vs ≤1 vertebral levels above the fracture (P < 0.001). Lateral angulation was more likely when the approach was made ≤1 vs ≥2 levels above the fracture (P < 0.001). The coronal Cobb angle differed significantly (P < 0.01) between patients with lumbar and thoracic fractures. The immediate postoperative coronal Cobb angle correlated tightly with the sum of the screw angles (superior plus inferior posterior and/or inferior plus superior anterior). Lateral angulation may occur after surgical fixation of thoracic and lumbar fractures via an anterior approach. Non-parallelism between the vertebral screws and their corresponding endplates may predict postoperative lateral spinal angulation. Postoperative lateral angulation does not correlate with low back pain, quality of life, or preoperative lateral angulation.

Graphene Bragg gratings on microfiber

Graphene Bragg gratings (GBGs) on microfiber are proposed and investigated in this paper. Numerical analysis and simulated results show that the mode distribution, transmission loss, and central wavelength of the GBG are controllable by changing the diameter of the microfiber or the refractive index of graphene. Such type of GBGs with tunability may find important applications in optical fiber communication and sensing as all-fiber in-line devices.

[Clinical features and laboratory findings of adult Epstein-Barr virus associated T/NK lymphoproliferative disease]

The aim of this study was to analyze the clinical features and laboratory findings of adult Epstein-Barr virus associated T/NK cell lymphoproliferative disease (EBV+T/NK-LPD) and to investigate the early diagnosis and prognosis of EBV+T/NK-LPD. The clinical data of 19 adult patients with EBV+T/NK-LPD were retrospectively analyzed. The results indicated that there were 11 males and 8 females. The median age was 32 years (range: 20-70 years). The average duration from onset of symptoms to diagnosis was 3.5 months. The median survival time was 2.5 months. Unkown fever, hepatosplenomegaly, liver dysfunction and interstitial pneumonia were the main clinical features. High levels of β2-MG, LDH, TNF, IL-6 and significantly increased EBV-DNA level (median level > 10(6) copies/ml) were occurred in all the patients. Cytopenia was seen in 18 cases. Morphologically, atypical large granular lymphocytes and hemophagocytosis were common in bone marrow smears. Deletion of CD5 or CD7 were frequently observed in T/NK lymphocytes in bone marrow cells by flow cytometry. Bone marrow biopsy showed atypical lymphocyte interstitial infiltrated in 10 cases, while a few large cells infiltrated in 6 cases. Immunohistochemistry showed the expression of CD3(+)CD56(+) were seen in 2 cases, CD3(+)CD8(+) in 11 cases and CD3(+)CD4(+) in 3 cases. TIA-1 and EBER were positive in all biopsy specimens. Three cases underwent biopsy of lymph nodes showed reactive proliferations of lymphocytes. All the patients died of multiorgan failure. It is concluded that the fever, hepatosplenomegaly are the most common clinical features in adult EBV+T/NK-LPD, the bone marrow infiltration of EBV-infected T/NK lymphocytes and significantly increased EBV-DNA level can be observed in all cases, the clinical outcome of this disease is poor, these clinical and experimental features can be served as a reliable marker for the timely diagnosis of adult EBV+T/NK-LPD.

Cadmium exposure and its health effects: a 19-year follow-up study of a polluted area in China

BACKGROUND

Dayu County, which is located in southwestern Jiangxi Province in China, has been a cadmium (Cd)-contaminated area since the 1960s. A series of studies about Cd pollution were carried out in the 1980s. However, no further studies of the area were conducted during the following 19 years.

AIM

To observe cadmium (Cd) exposure levels and its health risks among residents living in contaminated areas that have been exposed to environmental cadmium pollution for 45 years.

METHODS

Subjects involved in the survey in 1987 were interviewed again in 2006. Rice and urine samples from surviving subjects were collected to assess the level of cadmium exposure. Urinary Cd (U-Cd), urinary β2-microglobulin (U-β2-M) and urinary N-acetyl-β-d-glucosaminidase (U-NAG) were used as biomarkers to evaluate renal function. A medical examination was also performed on all subjects to diagnose clinical symptoms of Cd-exposure.

RESULT

Of the 96 subjects of the 1987 study who were alive in 2006, a total of 76 subjects were successfully recruited to this study. The average cadmium concentration in rice from the exposed areas was 0.59 ± 0.41 mg/kg in 2006, the average concentration of U-Cd, U-β2-M and U-NAG from cadmium-exposed areas was 25.82 ± 0.20 μg/g Cr, 6525.71 ± 0.93 μg/g Cr and 13.65 ± 0.24 μmol/g Cr, respectively, in 2006. Compared with the 1987 results, the 2006 results showed that the U-β2-M level in the exposed areas increased significantly after 19 years (p<0.05). The levels of U-Cd and U-NAG did not significantly change over time.

CONCLUSION

The concentration of Cd in polluted areas in 2006 is higher than it was in 1987. Renal dysfunction has worsened after 45 years of continuous exposure. Thus, environmental protection and special procedures to remove cadmium in these areas require urgent consideration.

[Clinical analysis of 10 patients with de novo CD5 positive diffuse large B cell lymphoma]

To explore the clinical characteristics, diagnosis, treatment outcome and prognosis of de novo CD5 positive diffuse large B cell lymphoma (CD5(+)DLBCL), clinical data of 10 patients with pathologically confirmed CD5(+)DLBCL were retrospectively analyzed. The results indicated that 9 out of 10 patients were older than 60 years. All cases were in III/IV stages according to Ann-Arbor Staging System. Bone marrow biopsy with immunohistochemistry showed lymphoma involvement in 5 cases. Nine patients received chemotherapy with anti-CD20 monoclonal antibody (Rituximab) except one. Five cases achieved CR, two cases achieved PR, two cases achieved SD, one case achieved PD. Eight cases died within 2 years because of relapse or disease progression, in which 3 cases developed central nervous system lymphoma. The median survival time was 16 (1-23) months, 2-year survival rate was 20.40%. It is concluded that de novo CD5(+) DLBCL is rare in clinic, but it is a kind of highly aggressive lymphoma with poor prognosis. So, new treatment strategy should be explored.

Random fiber laser formed by mixing dispersion compensated fiber and single mode fiber

Taking advantage of relatively strong Rayleigh scattering and Raman gain of dispersion compensated fiber (DCF), three configurations to form efficient random fiber lasers (RFL) are proposed in this paper. Compared with the reported RFL formed by single-mode fiber (SMF) solely, lasing threshold and length of the proposed RFL are effectively reduced through combination of DCF and SMF. In addition, FBGs with central wavelengths at the 1st and 2nd -order Raman Stokes wavelengths are also added to the hybrid SMF/DCF cavity to further reduce the lasing threshold, leading to realization of a new kind of 2nd-order RFL.

Hybrid lasing in an ultra-long ring fiber laser

In this paper, we reported the realization of an ultra-long ring fiber laser (RFL) with hybrid emission related to both random lasing and cavity resonance. Compared with a linear random fiber laser (LRFL), the Rayleigh scattering (RS) inducting distributed feedback effect and the cavity inducting resonance effect exist simultaneously in the laser, which reduces the lasing threshold considerably and provides a hybrid way to form random lasing (RL). The laser output can be purely modeless RL when pump power is high enough. It is also discovered that the laser is insensitive to temperature variation and mechanical disturbance, this is unique and quite different from conventional RFLs which are environmentally unstable due to existence of the cavity modes.

Long-distance fiber-optic point-sensing systems based on random fiber lasers

We find that the random fiber laser (RFL) without point-reflectors is a temperature-insensitive distributed lasing system for the first time. Inspired by such thermal stability, we propose the novel concept of utilizing the RFL to achieve long-distance fiber-optic remote sensing, in which the RFL offers high-fidelity and long-distance transmission for the sensing signal. Two 100 km fiber Bragg grating (FBG) point-sensing schemes based on RFLs are experimentally demonstrated using the first-order and the second-order random lasing, respectively, to verify the concept. Each sensing scheme can achieve >20 dB optical signal-to-noise ratio (OSNR) over 100 km distance. It is found that the second-order random lasing scheme has much better OSNR than that of the first-order random lasing scheme due to enhanced lasing efficiency, by incorporating a 1455 nm FBG into the lasing cavity.

Butanol production from corncob residue using Clostridium beijerinckii NCIMB 8052

AIMS

 To determine whether corncob residue (CCR) could be a good substrate for butanol production.

METHODS AND RESULTS

In this study, Ca(OH)₂ detoxification technique was used to remove inhibitors of lignocellulose enzymatic hydrolysis. During fermentation of untreated corncob residue hydrolysate (CCRH) by Clostridium beijerinckii NCIMB 8052, cell growth was inhibited and only 3·8 g l⁻¹ acetone, butanol and ethanol (ABE) was produced. After pretreatment with Ca(OH)₂, enzymatic hydrolysis of CCR resulted in 49·3 g l⁻¹ total sugars, about twofold of that of untreated one. In the fermentation of the Ca(OH)₂-detoxified CCRH, sugar utilization ratio was increased by 27·3%. When using the Ca(OH)₂-detoxified CCRH supplemented with 10 g l⁻¹ glucose, 16·0 g l⁻¹ ABE was produced, resulting in an ABE yield of 0·32 and a productivity of 0·33 g l⁻¹ h⁻¹.

CONCLUSION

The results in this study suggest that CCR was a good carbon source for ABE fermentation.

SIGNIFICANCE AND IMPACT OF THE STUDY

 It is the first time to use CCR as substrate for butanol production. Ca(OH)₂ detoxification pretreatment was proved to be an effective method to improve enzymatic digestibility of lignocellulose.

An improved reverse dot hybridization for simple and rapid detection of adefovir dipivoxil-resistant hepatitis B virus

Early detection of adefovir dipivoxil-resistant mutants during long-term treatment of chronic hepatitis B virus (HBV) infection with this drug is of great clinical importance. We developed an improved reverse dot hybridization test for simple and rapid detection of the rtA181V/T and rtN236T mutations associated with adefovir dipivoxil resistance in chronic hepatitis B patients. Probes were designed for genotypes B, C, and D of this resistance characteristic; a total of 70 clinical samples were analyzed with this improved reverse dot hybridization assay. Its usefulness was validated by comparing with sequencing data. Discordant results were confirmed by subclone sequencing. This reverse dot hybridization assay was sufficiently sensitive to detect 10(3) copies/mL; it also detected adefovir dipivoxil-resistant mutant strains when they comprised more than 5% of a mixed virus population. This reverse dot hybridization array correctly identified adefovir dipivoxil-resistant mutants; it had high concordance (98.5%) with direct sequencing data. There was no clear relationship between the HBV genotype and the development of adefovir dipivoxil-resistant mutants. This reverse dot hybridization assay proved to be simple and rapid for detection of rtA181V/T and rtN236T mutations associated with resistance to adefovir dipivoxil.

Detection of dental root fractures by using cone-beam computed tomography

OBJECTIVES

The purpose of this study was to compare the diagnostic accuracy of cone beam CT (CBCT) with that of conventional dental radiography in the detection of root fractures and to evaluate the influence of root canal fillings on root fracture detection.

METHODS

We investigated 128 patients with clinically suspected root fractures in 135 teeth. These patients underwent conventional dental radiography, CBCT and eventually surgical exploration. Among the 135 teeth, 86 were non-endodontically treated teeth and 49 were endodontically treated teeth. Two oral radiologists independently analysed the dental radiographs and CBCT images of each patient and reached a consensus. The CBCT findings of root fractures were set as the detection of a separation of the adjacent root segments on at least two contiguous sections and on at least two of the three-dimensional (3D) planes.

RESULTS

Root fracture was intraoperatively detected in 95 of the 135 teeth. The sensitivity and specificity of root fractures diagnosed on the basis of the consensus between the 2 evaluators were 26.3% and 100%, respectively, for dental radiography and 89.5% and 97.5%, respectively, for CBCT. CBCT was significantly more accurate than dental radiography in detecting root fractures (P < 0.001). The sensitivity of CBCT was reduced in the presence of root canal fillings but its specificity remained unaffected. Both the sensitivity and specificity of dental radiography were not influenced by the presence of root canal fillings.

CONCLUSIONS

CBCT appears to be more accurate than conventional dental radiography in the detection of root fractures.

[Macrophage apoptosis and the levels of interleukin-1 and interleukin-8 in the rats exposed to silica]

OBJECTIVE

To study the roles of macrophage apoptosis, IL-1, and IL-8 in the pathogenesis of rat pulmonary fibrosis induced by silica.

METHODS

Forty eight male Wistar rats were divided into the 4 control groups (24 rats) and 4 experimental groups (24 rats). Rats in the control groups were treated with 1 ml normal saline by trachea instillation, whereas the rats in experimental groups were exposed 1 ml silica suspension (100 mg/ml) by trachea instillation for 1, 7, 14 and 28 days, respectively. Six rats of each group were sacrificed, then the bronchoalveolar lavage fluid and lung tissues were collected, respectively. Pulmonary inflammation, fibrosis and other pathological changes were detected with H.E. staining. Morphological changes of the early stage apoptosis in macrophages were detected with transmission electron microscope (TEM). The early apoptosis rates of macrophages in BALF were also assessed using Annexin V-FITC/PI kit. The IL-1 and IL-8 levels of serum were measured with the ELISA.

RESULTS

The apoptotic rates (11.48% +/- 0.24%, 16.03% +/- 0.68%, 15.53% +/- 1.07%, 18.92% +/- 2.70%, respectively) of macrophage in the experimental groups increased obviously with time, as compared to the controls (5.47% +/- 2.06%, 6.39% +/- 0.215, 9.07% +/- 0.61% and 8.54% +/- 0.16%, Respectively) (P < 0.05). The IL-1 levels of serum in the experimental groups were 23.64 +/- 0.84, 23.38 +/- 1.10, 22.21 +/- 0.86 and 24.29 +/- 1.31 pg/ml, respectively, which were significantly higher than those (18.52 +/- 1.23, 18.40 +/- 1.6, 17.92 +/- 2.21 and 18.53 +/- 2.64 pg/ml, respectively) in the control groups (P < 0.05) without time-effect relationship. The serum IL-8 levels on the 1st, 7th and 14th days in the experimental groups were 21.32 +/- 1.44, 21.90 +/- 2.08 and 22.00 +/- 2.80 pg/ml, respectively, which were significantly higher than those (17.69 +/- 1.09, 16.98 +/- 2.09 and 17.54 +/- 1.62 pg/ml, respectively) in the control groups (P < 0.05).

CONCLUSION

The early macrophage apoptosis and changes of IL-1 and IL-8 may in lungs may play an important role in the development of pulmonary fibrosis induced by silica.

Reduced tibial speed of sound in Chinese infants at birth compared with Caucasian peers: the effects of race, gender, and vitamin D on fetal bone development

SUMMARY

This study compared bone status between Chinese and Caucasian infants at birth, showing that Chinese neonates have lower tibial speed of sound, which is influenced by gender, gestational age, season of birth, and maternal vitamin D status. The effects of these factors on fetal bone development were discussed.

INTRODUCTION

We compared the differences of speed of sound (SOS) accessed by quantitative ultrasound between Chinese and Caucasian infants at birth and explored the relationship between the concentrations of serum 25-hydroxyvitamin D [25(OH)D] and bone SOS in maternal-infant pairs.

METHODS

SOS for the tibial bone was measured at birth in 267 Chinese infants. We used the Z-scores for the direct comparisons which were available from the instrument based data of gender and age-matched Caucasian peers. The concentrations of serum 25(OH)D and bone SOS in 32 maternal-infant pairs were measured at birth in winters.

RESULTS

the Chinese infants had lower SOS demonstrated by the Z-scores. Significant differences of SOS and Z-scores were found between genders, gestational ages, birth weight, and seasons of birth. The differences of Z-scores negatively decreased with gestational age, suggesting that the bone status of Chinese infants lags behind that of the Caucasian infants during the last trimester of pregnancy in utero. The tibial SOS of infants born in winters was 2.0% higher than those born in summers after adjustment. The infant SOS correlated with maternal serum 25(OH)D (r = 0.399, P = 0.024) and infant serum 25(OH)D (r = 0.394, P = 0.026).

CONCLUSIONS

Chinese neonates have lower SOS which is influenced by gender, gestational age, season of birth, and maternal vitamin D status. It is inferred that, in pace with gestational age, race and gender effects on fetal bone development are modified by materno-fetal vitamin D status.

Vectorial polariton solitons in semiconductor microcavities

This paper presents numerical studies of vectorial polariton solitons in semiconductor microcavities. In the simulation, polarization degree of freedom of the polariton fields is taken into consideration. In the bistable regime, bright and/or dark solitons are found to bifurcate from the homogonous solutions of the two circular polarization modes. The combinations of solitons in the two polarization directions can be bright-dark, dark-bright, bright-bright, and dark-dark.

Nanostructured lipid carriers constituted from high-density lipoprotein components for delivery of a lipophilic cardiovascular drug

To investigate the possibility of reconstituted protein-free high-density lipoprotein (HDL) being a carrier for delivering a lipophilic cardiovascular drug, Tanshinone IIA-loaded HDL-like nanostructured lipid carriers (TA-NLC) were prepared by a nanoprecipitation/solvent diffusion method. The physicochemical parameters of TA-NLC were characterized in terms of particle size, zeta potential, morphology, entrapment efficiency, differential scanning calorimetry (DSC) and stability. A novel two-step method has been employed to determine entrapment efficiency of TA-NLC. The binding properties of TA-NLC to apolipoproteins were investigated by in vitro incubation competition assay in the presence of native HDL and electrophoresis test. Phagocytosis and cytotoxicity was evaluated using mouse macrophage cell line RAW 264.7 with TA-NLC and incubated TA-NLC with native HDL (TA-NLC-apo). The results showed that TA-NLC had an average diameter of 8.0+/-1.2 nm, zeta potential of -29.0+/-0.0 mV, drug loading of 6.17+/-0.3% and entrapment efficiency of 97.84+/-1.2%. TA-NLC were demonstrated spheres with drug incorporated in lipid core forming a shell-core structure. DSC analysis showed that TA was dispersed in NLC in an amorphous state. The incorporation of glycerol trioleate to NLC led to crystal order disturbance. Agarose gel electrophoresis and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-SPAGE) patterns indicated that TA-NLC could bind to apolipoprotein A-I (apoA-I) specifically in vitro. Phagocytosis studies showed significant differences in uptake between TA-NLC and TA-NLC-apo and demonstrated that TA-NLC incubated with native HDL could turn endogenous by association to apolipoproteins, which cannot trigger immunological responses and could escape from recognition by macrophages.

Focal adhesion plaque associated cytoskeletons are involved in the invasion and metastasis of human colorectal carcinoma

The protein and mRNA expression of focal adhesion plaque associated cytoskeletons, including talin, vinculin, paxillin, and tensin, was studied using immunofluorescence in combination with confocal laser scanning microscopy and fluorescent quantitative polymerase chain reaction in 41 matched samples of human normal colorectal mucosae, primary colorectal adenocarcinomas, and 19 separate lymph node metastases. All specimens showed expression. The results showed talin, vinculin, tensin, and paxillin expression were correlated with carcinogenesis, invasion, and metastasis of colorectal carcinoma (CRC). Talin, vinculin, and tensin underwent downregulation while paxillin went up. So these cytoskeletons may play bidirectional regulating roles during the progression of CRC.

Stealth tanshinone IIA-loaded solid lipid nanoparticles: effects of poloxamer 188 coating on in vitro phagocytosis and in vivo pharmacokinetics in rats

Stealth tanshinone IIA-loaded solid lipid nanoparticles (TA-SSLNs) have been prepared and the influence of poloxamer 188 coating on in vitro phagocytosis and in vivo pharmacokinetics in rats were evaluated. TA-SSLNs have been prepared by a nanoprecipitation/solvent diffusion method. Poloxamer 188 was used as a stealth agent. The physicochemical parameters of TA-SSLNs were characterized in terms of particle size, zeta potential, transmission electron microscopy and stability. In vitro, phagocytosis was investigated by incubating TA-SSLNs and non-stealth tanshinone IIA-loaded solid lipid nanoparticles (TA-NSLNs) with murine macrophages. In vivo, pharmacokinetics of TA-SSLNs and TA-NSLNs after a single dose intravenous injection to rat has been studied. The control was tanshinone IIA solution (TA-SOL). The results showed that TA-SSLNs had an average diameter of (91.3 +/- 3.4) nm, zeta potential of (-19.7 +/- 1.6) mV, drug loading of (4.7 +/- 0.5) % and entrapment efficiency of (92.5 +/- 2.1) %. Phagocytosis studies showed significant differences between TA-SSLNs and TA-NSLNs and demonstrated that the poloxamer 188 coating could decrease the macrophage uptake. In vivo experiments showed that the plasma concentration data of TA-SSLNs, TA-NSLNs and TA-SOL were all fitted to a two-compartment model. Areas under curve (AUCs) of TA-NSLNs and TA-SSLNs were 1.28 and 3.70 times than that of TA-SOL, respectively. TA-SSLNs had generated a long circulating time in blood with a mean residence time (MRT) of 5.286 h, compared to 3.051 h of TA-NSLNs and 0.820 h of TA-SOL. Poloxamer 188 modification on solid lipid nanoparticles (SLNs) reduced opsonization by serum proteins and the macrophage uptake. AUC of tanshinone IIA increased as a function of SLNs. In addition, TA-SSLNs exhibited much longer circulation lifetimes for tanshinone IIA than TA-NSLNs. The pharmacokinetic behavior of the incorporated drug can be modified by changing the surface characteristics of SLNs with the use of poloxamer 188.

[Expressions of heat shock protein (HSP) family HSP 60, 70 and 90alpha in colorectal cancer tissues and their correlations to pathohistological characteristics]

BACKGROUND AND OBJECTIVE

Colorectal cancer is the third common malignant tumor in the world. Heat shock protein (HSP) family has been reported to play an important role in carcinogenesis of various cancers. However, little is known about expressions of HSP60,HSP70 and HSP90alpha in colorectal cancer. This study was to investigate expressions of HSP 60, 70 and 90alpha, and analyzed their correlations to pathohistologic characteristics in colorectal cancer.

METHODS

Colorectal cancer tissues and adjacent normal tissues 2 cm away from the tumor focus were collected from 49 patients. Expressions of HSP60, HSP70 and HSP90alpha mRNA were detected by RT-PCR. The protein expressions of HSP60, HSP70 and HSP90alpha were determined by immunohistochemistry and western blot.

RESULTS

The mRNA and protein levels of HSP60, HSP70 and HSP90alpha, as well as their positive rates were significantly increased in tumor tissues compared with those in para-cancerous tissues. The overexpression rates of HSP60, HSP70 and HSP90alpha were also significantly higher in the colorectal cancer tissues than those in the corresponding para-cancerous tissues. The positive and overexpression rates of HSP60, HSP70 and HSP90alpha in well, moderately and poorly differentiated colorectal cancer were not significantly different.

CONCLUSIONS

HSP60, HSP70 and HSP90alpha may play important roles in the pathogenesis of colorectal cancer, although they are not correlated with the pathological grading.

Coffee consumption and risk of cardiovascular events and all-cause mortality among women with type 2 diabetes

AIMS/HYPOTHESIS

Coffee has been linked to both beneficial and harmful health effects, but data on its relationship with cardiovascular disease and mortality in patients with type 2 diabetes are sparse.

METHODS

This was a prospective cohort study including 7,170 women with diagnosed type 2 diabetes but free of cardiovascular disease or cancer at baseline. Coffee consumption was assessed in 1980 and then every 2-4 years using validated questionnaires. A total of 658 incident cardiovascular events (434 coronary heart disease and 224 stroke) and 734 deaths from all causes were documented between 1980 and 2004.

RESULTS

After adjustment for age, smoking and other cardiovascular risk factors, the relative risks were 0.76 (95% CI 0.50-1.14) for cardiovascular diseases (p trend = 0.09) and 0.80 (95% CI 0.55-1.14) for all-cause mortality (p trend = 0.05) for the consumption of >or=4 cups/day of caffeinated coffee compared with non-drinkers. Similarly, multivariable RRs were 0.96 (95% CI 0.66-1.38) for cardiovascular diseases (p trend = 0.84) and 0.76 (95% CI 0.54-1.07) for all-cause mortality (p trend = 0.08) for the consumption of >or=2 cups/day of decaffeinated coffee compared with non-drinkers. Higher decaffeinated coffee consumption was associated with lower concentrations of HbA(1c) (6.2% for >or=2 cups/day versus 6.7% for <1 cup/month; p trend = 0.02).

CONCLUSIONS

These data provide evidence that habitual coffee consumption is not associated with increased risk of cardiovascular diseases or premature mortality among diabetic women.

catena-Poly[[[bis-(4-amino-benzoato-κO)copper(II)]-μ-1,1'-(pentane-1,5-di-yl)diimidazole] trihydrate]

In the title compound, {[Cu(C(7)H(6)NO(2))(2)(C(11)H(16)N(4))]·3H(2)O}(n), each Cu(II) atom is coordinated by two O atoms from two 4-amino-benzoate anions, and two N atoms from two different 1,1'-(pentane-1,5-di-yl)diimidazole (biim-5) ligands, to furnish a distorted square-planar geometry. The biim-5 ligand coordinates to two copper(II) cations, acting as a bridging ligand; as a result the copper(II) cations are connected to form an infinite chain structure. The polymeric chains are linked through a variety of hydrogen bonds to form a three-dimensional structure.

Short Communication: Optimal Random Regression Models for Milk Production in Dairy Cattle

Legendre polynomials of orders 3 to 8 in random regression models (RRM) for first-lactation milk production in Canadian Holsteins were compared statistically to determine the best model. Twenty-six RRM were compared using LP of order 5 for the phenotypic age-season groupings. Variance components of RRM were estimated using Bayesian estimation via Gibbs sampling. Several statistical criteria for model comparison were used including the total residual variance, the log likelihood function, Akaike's information criterion, the Bayesian information criterion, Bayes factors, an information-theoretic measure of model complexity, and the percentage relative reduction in complexity. The residual variance always picks the model with the most parameters. The log likelihood and information-theoretic measure picked the model with order 5 for additive genetic effects and order 7 for permanent environmental effects. The currently used model in Canada (order 5 for both additive and permanent environmental effects) was not the best for any single criterion, but was optimal when considering all criteria.

Heavy metal and Pb isotopic compositions of aquatic organisms in the Pearl River Estuary, South China

The accumulation of trace metals in aquatic organisms may lead to serious health problems through the food chain. The present research project aims to study the accumulation and potential sources of trace metals in aquatic organisms of the Pearl River Estuary (PRE). Four groups of aquatic organisms, including fish, crab, shrimp, and shellfish, were collected in the PRE for trace metal and Pb isotopic analyses. The trace metal concentrations in the aquatic organism samples ranged from 0.01 to 2.10 mg/kg Cd, 0.02 to 4.33 mg/kg Co, 0.08 to 4.27 mg/kg Cr, 0.15 to 77.8 mg/kg Cu, 0.17 to 31.0 mg/kg Ni, 0.04 to 30.7 mg/kg Pb, and 8.78 to 86.3 mg/kg Zn (wet weight). High concentrations of Cd were found in crab, shrimp and shellfish samples, while high concentration of Pb was found in fish. In comparison with the baseline reference values in other parts of the world, fish in the PRE had the highest elevated trace metals. The results of Pb isotopic compositions indicated that the bioaccumulation of Pb in fish come from a wide variety of food sources and/or exposure pathways, particularly the anthropogenic inputs.

Monitoring of pollution of air fine particles (PM2.5) and study on their genetic toxicity

OBJECTIVE

To compare PM2.5 pollation level between the city of coal-fuel pollution (Taiyuan) and the city of pollution mixed with coal fuels and vehicle exhausts (Beijing), to analyze the concentration of B[a]p and Pb in the pollutants, and to study the DNA damage by PM2.5.

METHODS

Air fine particles (PM2.5) were collected in Beijing and Taiyuan by means of the filter membrane method, the concentration of B[a]p and Pb were analyzed by high performance liquid chromatography and atomic absorption spectroscopy respectveily, and the damage of DNA by PM2.5 was detected by single cell gel-electrophoresis (SCGE) using the human lung epithelial cells (A549) as target cells.

RESULTS

The concentration of PM2.5 in the winter of Beijing was 0.028-0.436 mg/m(3), and that in Taiyuan was 0.132-0.681 mg/m(3). The concentration of B[a]p was 0.104 and 0.156 microg/mg on PM2.5 of Beijing and Taiyuan, respectively, whereas the concentration of Pb was 1.094 and 1.137 microg/mg on PM2.5 of Beijing and Taiyuan, respectively. Exposure to PM2.5 at the concentrations of 5, 50, and 200 microg/mL for 12 h and 24 h caused DNA damage of the human alveolar epithelium, and the ratios of the tailing and length of the tail were all significantly different from those of the negative control group (P < 0.05), and indicated a dose-response relationship.

CONCLUSION

PM2.5 has certain genetic toxicity.

[On cleanliness of hands in diminution of Ascaris lumbricoides infection in children]

OBJECTIVE

To study the relationship between cleanliness of children's hands and diminution of Ascaris lumbricoides infection.

METHODS

Before the study all persons positive for ascaris eggs in the preliminary survey were treated with albendazole. Hand-washing habit before meal and after defecation was kept in children of experimental group, but not in the control group. Kato thick smear stool examination was done once every two months for one year to compare the new infection rates in children without ascaris infection in the two groups, and the reinfection rates in the cured negative cases were also compared between them in half a month after chemotherapy.

RESULTS

All the new infection rates as well as reinfection rates of each reexamination in the experimental group were significantly lower than that of the control group (P < 0.001). Reexamination one year later showed that the ascaris infection rate of the experimental group was 35.2%, reducing by 48.5% as compared with 68.3% before the operation of the project; while ascaris infection rate of the control group was 73.7%, increasing by 78.0% as compared with 41.4% before the operation of the project.

CONCLUSION

Washing hands with toilet soap to keep hands clean can significantly reduce ascaris infection rate.

Preliminary study of phosphorus runoff and drainage from a paddy field in the Taihu Basin

An investigation into phosphorus runoff and drainage from a paddy field was carried out at Changshu Agricultural Ecological Station of CAS during the year 2000. According to the preliminary study, some results indicated: (1) Total phosphorus (TP) content of regular irrigation water was 19 times higher than TP content of P0 (zero rate of P fertilization) stand water. This indicates that paddy fields are a potential source of phosphorus pollution by runoff and drainage into the Taihu Lake Basin (TLB); (2) During the first 10 days after phosphate fertilizer application, the TP concentration of stand water in the paddy field was very high, therefore this was the high risk period for Taihu Lake phosphorus contamination; (3) Four mathematical models of P losses from a paddy field in the TLB are developed. These are based on data for the year 2000, but they will be improved as more data is acquired in future years.