A chromosome-level genome assembly of the spider mite Tetranychus piercei McGregor

Despite the rapid advances in sequencing technology, limited genomic resources are currently available for phytophagous spider mites, which include many important agricultural pests. One of these pests is Tetranychus piercei (McGregor), a serious banana pest in East Asia exhibiting remarkable tolerance to high temperature. In this study, we assembled a high-quality genome of T. piercei using a combination of PacBio long reads and Illumina short reads sequencing. With the assistance of chromatin conformation capture technology, 99.9% of the contigs were anchored into three pseudochromosomes with a total size of 86.02 Mb. Repetitive elements, accounting for 14.16% of this genome (12.20 Mb), are predominantly composed of long-terminal repeats (30.7%). By combining evidence of ab initio prediction, transcripts, and homologous proteins, we annotated 11,881 protein-coding genes. Both the genome and proteins have high BUSCO completeness scores (>94%). This high-quality genome, along with reliable annotation, provides a valuable resource for investigating the high-temperature tolerance of this species and exploring the genomic basis that underlies the host range evolution of spider mites.

[Clinical effects of flaps or myocutaneous flaps transplantation after titanium mesh-retaining debridement in repairing the wounds with exposed titanium mesh after cranioplasty]

Objective: To explore the clinical effects of flaps or myocutaneous flaps transplantation after debridement to repair the wounds with exposed titanium mesh after cranioplasty on the premise of retaining the titanium mesh. Methods: This study was a retrospective observational study. From February 2017 to October 2022, 22 patients with titanium mesh exposure after cranioplasty who met the inclusion criteria were admitted to the Department of Plastic, Aesthetic & Maxillofacial Surgery of the First Affiliated Hospital of Xi'an Jiaotong University, including 15 males and 7 females, aged from 19 to 68 years. After admission, treatments such as bacterial culture of wound exudate sample, anti-infection, and dressing change were carried out. Thorough surgical debridement was performed when the wound improved, and the wound area was 3.0 cm×2.0 cm to 11.0 cm×8.0 cm after debridement. The wound was repaired with local flaps, expanded flaps, or free latissimus dorsi myocutaneous flaps according to the size, location, severity of infection, and surrounding tissue condition of the wounds, and the areas of flaps or myocutaneous flaps were 5.5 cm×4.0 cm to 18.0 cm×15.0 cm. The donor areas of flaps were sutured directly or repaired by split-thickness skin grafts from head. The wound repair method was recorded. The survivals of flaps or myocutaneous flaps after surgery and wound healing in 2 weeks after surgery were recorded. During postoperative follow-up, recurrence of infection or titanium mesh exposure in the implanted area of titanium mesh was observed; the head shapes of patients, scar formation of the operative incision, and baldness were observed. At the last follow-up, the satisfaction of patients with the treatment effect (dividing into three levels: satisfied, basically satisfied, and dissatisfied) was evaluated. The total treatment costs of patients during their hospitalization were calculated. Results: The wounds in 11 cases were repaired with local flaps, the wounds in 5 cases were repaired with expanded flaps, and the wounds in 6 cases were repaired with free latissimus dorsi myocutaneous flaps. All flaps or myocutaneous flaps survived completely after surgery, and all wounds healed well in 2 weeks after surgery. Follow up for 6 to 48 months after operation, only one patient with local flap grafting experienced a recurrence of infection in the titanium mesh implanted area at more than one month after surgery, and the titanium mesh was removed because of ineffective treatment. Except for one patient who had a local depression in the head after removing the titanium mesh, the rest of the patients had a full head shape. Except for myocutaneous flap grafting areas in 6 cases and skin grafting area in 1 case with local flaps grafting had no hair growth, the other patients had no baldness. All the scars in surgical incision were concealed. At the last follow-up, 19 cases were satisfied with the treatment effects, 2 cases were basically satisfied, and 1 case was dissatisfied. The total treatment cost for patients in this group during hospitalization was 11 764-36 452 (22 304±6 955) yuan. Conclusions: For patients with titanium mesh exposure after cranioplasty, on the premise of adequate preoperative preparation and thorough debridement, the wound can be repaired with appropriate flaps or myocutaneous flaps according to the wound condition. The surgery can preserve all or part of the titanium mesh. The postoperative wound healing is good and the recurrence of infection or titanium mesh exposure in the titanium mesh implanted area is reduced, leading to good head shape, reduced surgical frequency, and decreased treatment costs.

Impact of preoperative [18F]FDG PET/CT vs. contrast-enhanced CT in the staging and survival of patients with clinical stage I and II non-small cell lung cancer: a 10-year follow-up study

OBJECTIVES

To elucidate the impact of [18F]FDG positron emission tomography/computed tomography (PET/CT) vs. CT workup on staging and prognostic evaluation of clinical stage (c) I-II NSCLC.

METHODS

We retrospectively identified 659 cI-II NSCLC who underwent CT (267 patients) or preoperative CT followed by PET/CT (392 patients), followed by curative-intended complete resection in our hospital from January 2008 to December 2013. Differences were assessed between preoperative and postoperative stage. Five-year disease-free survival (DFS) and overall survival (OS) rates were calculated using the Kaplan-Meier approach and compared with log-rank test. Impact of preoperative PET/CT on survival was assessed by Cox regression analysis.

RESULTS

The study included 659 patients [mean age, 59.5 years ± 10.8 (standard deviation); 379 men]. The PET/CT group was superior over CT group in DFS [12.6 vs. 6.9 years, HR 0.67 (95% CI 0.53-0.84), p < 0.001] and OS [13.9 vs. 10.5 years, HR 0.64 (95% CI 0.50-0.81), p < 0.001]. In CT group, more patients thought to have cN0 migrated to pN1/2 disease as compared with PET/CT group [26.4% (66/250) vs. 19.2% (67/349), p < 0.001], resulting in more stage cI cases being upstaged to pII-IV [24.7% (49/198) vs. 16.1% (47/292), p = 0.02], yet this was not found in cII NSCLC [27.5% (19/69) vs. 27.0% (27/100), p = 0.94]. Cox regression analysis identified preoperative PET/CT as an independent prognostic factor of OS and DFS (p = 0.002, HR = 0.69, 95% CI 0.54-0.88; p = 0.004, HR = 0.72, 95% CI 0.58-0.90).

CONCLUSION

Addition of preoperative [18F]FDG PET/CT was associated with superior DFS and OS in resectable cI-II NSCLC, which may result from accurate staging and stage-appropriate therapy.

Identification and characterization of an L-type lectin from obscure puffer Takifugu obscurus in response to bacterial infection

L-type lectins (LTLs) contain a carbohydrate recognition domain homologous to leguminous lectins, and have functions in selective protein trafficking, sorting and targeting in the secretory pathway of animals. In this study, a novel LTL, designated as ToERGIC-53, was cloned and identified from obscure puffer Takifugu obscurus. The open reading frame of ToERGIC-53 contained 1554 nucleotides encoding 517 amino acid residues. The deduced ToERGIC-53 protein consisted of a signal peptide, a leguminous lectin domain (LTLD), a coiled-coil region, and a transmembrane region. Quantitative real-time PCR showed that ToERGIC-53 was expressed in all examined tissues, with the highest expression level in the liver. The expression of ToERGIC-53 was significantly upregulated after infection with Vibrio harveyi and Staphylococcus aureus. Recombinant ToERGIC-53-LTLD (rToERGIC-53-LTLD) protein could not only agglutinate and bind to one Gram-positive bacterium (S. aureus) and three Gram-negative bacteria (V. harveyi, V. parahaemolyticus and Aeromonas hydrophila), but also bind to glycoconjugates on the surface of bacteria such as lipopolysaccharide, peptidoglycan, mannose and galactose. In addition, rToERGIC-53-LTLD inhibited the growth of bacteria in vitro. All these results suggested that ToERGIC-53 might be a pattern recognition receptor involved in antibacterial immune response of T. obscurus.

Three novel L-type lectins from obscure puffer Takifugu obscurus promote antimicrobial immune response

L-type lectins (LTLs) have leguminous lectin domains that bind to high-mannose-type oligosaccharides. LTLs are involved in glycoprotein secretory pathways and associated with many immune responses. In the present research, three LTL homologs from obscure puffer Takifugu obscurus, designated as ToVIP36-1, ToVIP36-2, and ToVIP36-3, were first cloned and identified. The open reading frames of ToVIP36-1, ToVIP36-2, and ToVIP36-3 were 1068, 1002, and 1086 bp in length, respectively, and encode polypeptides with 355, 333, and 361 amino acids, respectively. Key conserved residues and functional domains, including lectin_leg-like domain (LTLD), transmembrane region, and C-terminal trafficking signal KRFY, were identified in all ToVIP36s. Quantitative real-time PCR analysis showed that the three ToVIP36s were widely expressed in six examined tissues and had relatively high expression levels in the liver and intestine. The expression levels of ToVIP36s were remarkably altered in the liver and kidney after induction by Vibrio harveyi and Staphylococcus aureus. Subsequently, the recombinant LTLDs of ToVIP36s (rToVIP36-LTLDs) were prepared by prokaryotic expression. Three rToVIP36-LTLD proteins agglutinated with S. aureus, V. harveyi, Vibrio parahaemolyticus, and Aeromonas hydrophila in a calcium-dependent manner. In the absence of calcium, rToVIP36-LTLD proteins bound to the bacteria by binding to lipopolysaccharides, peptidoglycans, d-mannose, and d-galactose and inhibited the growth of S. aureus and V. harveyi. Our results indicated that ToVIP36s function as pattern-recognition receptors in T. obscurus immunity, providing insights into the role of LTLs in the antibacterial immunity of fishes.

The genome sequence of a spider mite, Tetranychus truncatus, provides insights into interspecific host range variation and the genetic basis of adaptation to a low-quality host plant

The phytophagous mite Tetranychus truncatus is a serious pest in East Asia but has a relatively narrower host range than the pest mite Tetranychus urticae, which can feed on over 1200 plant species. Here, we generated a high-quality chromosomal level genome of T. truncatus and compared it with that of T. urticae, with an emphasis on the genes related to detoxification and chemoreception, to explore the genomic basis underlying the evolution of host range. We also conducted population genetics analyses (in 86 females from 10 populations) and host transfer experiments (in 4 populations) to investigate transcription changes following transfer to a low-quality host (Solanum melongena, eggplant), and we established possible connections between fitness on eggplant and genes related to detoxification and chemoreception. We found that T. truncatus has fewer genes related to detoxification, transport, and chemoreception than T. urticae, with a particularly strong reduction in gustatory receptor (GR) genes. We also found widespread transcriptional variation among T. truncatus populations, which varied in fitness on eggplant. We characterized selection on detoxification-related genes through ω values and found a negative correlation between expression levels and ω values. Based on the transcription results, as well as the fitness and genetic differences among populations, we identified genes potentially involved in adaptation to eggplant in T. truncatus. Our work provides a genomic resource for this pest mite and new insights into mechanisms underlying the adaptation of herbivorous mites to host plants.

[Research advances on the treatment of diabetic foot ulcers with autologous platelet-rich fibrin]

Diabetic foot is one of the serious complications of diabetic patients, which makes the society and public health bear a huge economic burden. In recent years, more and more studies at home and abroad have been conducted on the treatment of chronic wounds with autologous platelet-rich fibrin, and the therapeutic concepts and methods have been updated constantly. In this paper, we reviewed the general situation of autologous platelet-rich fibrin, the mechanism of autologous platelet-rich fibrin in promoting the healing of diabetic foot ulcers and the new progress in its application, so as to provide a new strategy for the repair of diabetic foot ulcers.

Phylogenetic-Related Divergence in Perceiving Suitable Host Plants among Five Spider Mites Species (Acari: Tetranychidae)

Spider mites belonging to the genus Tetranychus infest many important agricultural crops in both fields and greenhouses worldwide and are diversified in their host plant range. How spider mites perceive their suitable host plants remains not completely clear. Here, through two-host-choice designs (bean vs. tomato, and bean vs. eggplant), we tested the efficacies of the olfactory and gustatory systems of five spider mite species (T. urticae, T. truncatus, T. pueraricola, T. piercei, and T. evansi), which differ in host plant range in sensing their suitable host plant, by Y-tube olfactometer and two-choice disc experiments. We found that spider mites cannot locate their suitable host plants by volatile odours from a long distance, but they can use olfactory sensation in combination with gustatory sensation to select suitable host plants at a short distance. Highly polyphagous species displayed strong sensitivity in sensing suitable host plants rather than the lowered sensitivity we expected. Intriguingly, our principal component analyses (PCAs) showed that the similarity among five spider mite species in the performance of perceiving suitable host plants was highly correlated with their relative phylogenetic relationships, suggesting a close relationship between the chemosensing system and the speciation of spider mites. Our results highlight the necessity of further work on the chemosensing system in relation to host plant range and speciation of spider mites.

[Analysis of low-dose computed tomography compliance and related factors among high-risk population of lung cancer in three provinces participating in the cancer screening program in urban China]

Objective: To analyze the compliance and related factors of low-dose computed tomography (LDCT) screening among the high-risk population of lung cancer in three provinces participating in the cancer early diagnosis and early treatment program in urban areas of China. Methods: From October 2017 to October 2018, 17 983 people aged between 40 and 74 years old at high risk of lung cancer were recruited from Zhejiang, Anhui and Liaoning provinces. The basic demographic characteristics, living habits, history of the disease and family history of cancer were collected by using a cancer risk assessment questionnaire, and the data of participants examined by LDCT were obtained from the hospitals participating in the program. The screening compliance was quantified by the screening participation rate, and it was calculated as the proportion of participants completing LDCT scan among high-risk population. The related factors of LDCT screening compliance were analyzed by using a multivariate logistic regression model. Results: The age of 17 983 participants was (56.52±8.22) years old. Males accounted for 51.9% (N=9 332), and 69.5% (N=12 495) had ever smoked, including former smokers and current smokers. A total of 6 269 participants were screened by LDCT, and the screening participation rate was 34.86%. The results of multivariate logistic regression analysis showed that the age group of 50 to 69 years old, female, passive smokers, alcohol consumption, family history of lung cancer and history of chronic respiratory diseases were more likely to be screened by LDCT, while the compliance of LDCT screening in current smokers was low. Conclusions: The LDCT screening compliance of the high-risk population of lung cancer in urban areas of China still needs to be improved. Age, sex, smoking, drinking, family history of lung cancer and history of chronic respiratory disease are associated with screening compliance.

[Research advances in the relationship of dietary factors and prostate cancer risk]

Prostate cancer is the second most common malignancy in men worldwide. An increasing trend for prostate cancer incidence was observed in China. Enormous studies have been conducted to investigate the association between dietary factors and prostate cancer, however conflicted results were obtained. Red meat, processed meat, and dairy products consumption were reported to be associated with the increased prostate cancer risk, while tomatoes, soybeans and green tea might reduce the risk of prostate cancer occurance. However, no consensus could be reached without strong evidence. Furthermore, further studies are needed to investigate the association between vitamin and mineral supplements and prostate cancer risk. Some studies reported that men with higher dietary inflammatory index scores increased prostate cancer risk. There may be a long susceptible period when dietary factors affect prostate cancer risk, which poses challenges for collecting exposure and the follow-up. Measure bias and detection bias are the main reasons which impair the authenticity of studies on the relationship of dietary factors and prostate cancer risk. Researchers should apply various methods to measure participants' dietary consumption levels and ascertain essential outcomes, such as prostate cancer death. This article reviews updated epidemiological evidences on the association of dietary factors and prostate cancer, aims to benefit future nutritional epidemiology studies focus on the prostate cancer prevention.

[Application of the Virtual Reality-Pattern Visual Evoked Potential in Forensic Visual Acuity Evaluation]

Abstract

Objective To explore a kind of visual evoked potential test equipment and method that is more suitable for the application of forensic clinical visual acuity evaluation. Methods Thirty-four volunteers （68 eyes） were selected, including 15 males and 19 females, aged between 20 and 40 years. Test lenses were placed before the tested eyes of volunteers to induce refractive myopia with insert method, and the diopter lenses were adjusted so that the visual acuity level of one eye of volunteers was above 0.8, and the visual acuity of the other eye was at moderate damage level （<0.3 and ≥0.1）. The tests were carried out under the binocular simultaneous asynchronous stimulation mode （hereinafter referred to as "binocular mode"） and monocular separate stimulation mode （hereinafter referred to as "monocular mode"） of virtual reality-pattern visual evoked potential （VR-PVEP）, and the amplitude of PVEP of volunteers under the two modes was compared at four spatial frequencies of 8×8, 16×16, 24×24 and 32×32. Results The differences in the amplitude of P100 wave between monocular and binocular modes at 8×8 spatial frequency had no statistical significance and the differences in amplitude of P100 wave between monocular and binocular modes at 16×16, 24×24, and 32×32 spatial frequencies had statistical significance （P<0.05）. The amplitude of the same eye in monocular mode was higher than that in binocular mode. Through correlation analysis, it was found that the amplitude of P100 wave in monocular mode was moderately correlated with amplitude of P100 wave in binocular mode. Conclusion In forensic identification practice, VR-PVEP is helpful for overcoming the disturbance of poor fixation, and to increase the reliability of PVEP evaluation results. It can greatly shorten the detection time of PVEP and improve work efficiency.

[The prognostic significance of dynamic monitoring of minimal residual disease (MRD) status in patients with newly-diagnosed multiple myeloma]

Objective: To evaluate the prognostic value of kinetic changes in minimal residual disease (MRD) status, as well as its relationship with risk stratification, therapeutic response and treatment in patients with newly-diagnosed multiple myeloma (MM) . Methods: A total of 135 patients with newly-diagnosed MM were screened, and 105 patients who achieved VGPR or more as the best responses were included into this study. The MRD status was determined by multiparameter flow cytometry (MFC) at multiple intervals after two cycles of treatment until clinical relapse, death, or last follow-up. The statistical methods included Kaplan-Meier analysis, Cox regression, etc. Results: ①In all 135 patients, 57.8% (78/135) patients achieved MRD negativity (MRD(-)) after treatment. In 105 patients who achieved VGPR and thus included in this study, the MRD(-) rate was 72.4% (76/105) , with a median interval of 3 months from starting treatment to achievement of MRD(-) status. ②The 2-year PFS rate of patients with MRD(-) status was significantly higher than that of MRD(+) status (62.2% vs 41.3%, P=0.001) , while MRD persistence (MRD(+)) was an independent factor for poor prognosis (multivariate analysis for PFS: P=0.044, HR=3.039, 95%CI 1.029-8.974) . ③Loss of MRD(-) status (i.e., MRD reappearance) showed inferior outcomes compared with MRD sustained negative ones, the PFS was 18 months versus not reach (P<0.001) and the OS was not reach for both (P=0.002) . ④The 2-year PFS and OS rates of patients with duration of MRD(-)status≥12 months were significantly higher than those of the control group (PFS: 77.7% vs 36.7%, P<0.001; OS: 96.4% vs 57.9%, P<0.001 respectively) . Duration of MRD(-) status was associated with a marked reduction in risk of relapse or death (univariate analysis for PFS: P<0.001, HR=0.865, 95%CI 0.815-0.918; for OS: P=0.001, HR=0.850, 95%CI 0.741-0.915 respectively) . ⑤Moreover, even in patients carrying high-risk cytogenetic abnormalities (CA) or ineligible for ASCT, MRD negativity remained its prognostic value to predict PFS (high-risk CA medianPFS: not reach vs 19 months, P=0.006; ineligible for ASCT medianPFS: not reach vs 25 months, P=0.052 respectively) . ⑥Last, treatment with the bortezomib-based regimens contributed to prolonged MRD(-) duration (median MRD(-) duratio: 25 months vs 10 months, P=0.034) . Conclusion: Our findings supported MRD(+) status as an independent poor prognostic factor in MM patients, which implicated that duration of MRD(-) status also played a significant role in evaluation of prognosis, while loss of MRD(-)status might serve as an early biomarker for relapse. Therefore, monitoring of MRD kinetics might more precisely predict prognosis, as well as guide treatment decision, especially for when to start retreatment in relapsed patients.

[A multicenter cross-sectional study on chronic critical illness and surgery-related chronic critical illness in China]

Objective: To understand the prevalence, diagnosis and treatment of chronic critical illness (CCI) in China. Methods: The clinical data of 472 adult patients admitted to ICU in 53 hospitals, including basic information, disease-related data, nutrition program, etc., were collected on May 10, 2019, by means of multi-center cross-sectional study. If surgical intervention was needed or the occurrence of the disease was directly related to the surgery, ICU patients were regarded as surgical ICU cases (n=211). In this study, the diagnostic criteria for CCI were: (1) admission to ICU >14 days;(2) combined with persistent organ dysfunction. The prevalence,distribution and treatment of CCI and surgery-related CCI were recorded and analyzed. The Mann-Whitney U test, chi-square test or Fisher exact test were used for comparative analysis. Results: Among the 472 ICU patients from 53 hospitals, 326 were male (69.1%) and 146 were female (30.9%). The prevalence of CCI was 30.7% (145/472). Among 211 surgery-related ICU patients, 57 developed CCI with a prevalence of 27.0%. As compared to non-CCI patients, higher APACHE II score [median (IQR) 13.5 (10.0, 18.3) vs. 11.0 (7.0, 16.0), U=2970.000, P=0.007], higher Charlson comorbidity index [median (IQR) 4.0 (2.0, 7.0) vs. 3.0 (1.0, 5.0), U= 3570.000, P=0.036] and higher ratio of breath dysfunction [68.4% (39/57) vs. 48.1% (74/154), χ(2)=6.939, P=0.008] and renal dysfunction [42.1% (24/57) vs. 18.2% (28/154), χ(2)=12.821, P<0.001] were found in surgery-related CCI patients. While SOFA score, Glasgow coma score and other visceral function were not significantly different between surgery-related CCI and non-CCI patients (all P>0.05). NUTRIC score showed that surgery-related CCI patients had higher nutritional risk [43.9% (25/57) vs. 26.6%(41/154), U=5.750, P=0.016] and higher ratio of mechanical ventilation [66.7% (38/57) vs. 52.3% (79/154), χ(2)=3.977, P=0.046] than non-CCI patients. On the survey day, the daily caloric requirements of 50.2% (106/211) of surgery-related ICU patients were calculated according to the standard adult caloric intake index (104.6 to 125.5 kJ·kg(-1)·d(-1), 1 kJ=0.239 kcal), and the daily caloric requirements of 46.4% (98/211) of patients were calculated by physicians according to the severity of the patient's condition. 60.2% (127/211) of nutritional support therapy was enteral nutrition (including a combination of enteral and parenteral nutrition), while the remaining patients received parenteral nutrition (24.6%, 52/211), simple glucose infusion (9.0%, 19/211), or oral diet (6.2%, 13/211). The target calorie of CCI group was 104.6 (87.9, 125.5) kJ·kg(-1)·d(-1), and the actual calorie intake accounted for 0.98 (0.80, 1.00) of the target calory. In the non-CCI group, the target calorie was 104.6 (87.9, 125.5) kJ·kg(-1)·d(-1), and the actual calorie consumed accounted for 0.91 (0.66, 1.00) of the target calorie. There was no statistically significant difference between two groups (P=0.248, P=0.150). Conclusion: The prevalence of CCI and surgery-related CCI in ICU is high, along with severe complications, respiratory and renal dysfunction and mechanical ventilation. Surgical patients admitted to ICU are at high nutritional risk, and active and correct nutritional support is essential for such patients.

Application of PRVEP Waveform Amplitude Ratio to Evaluate Visual Acuity and Its Forensic Significance

Abstract

Objective To research the correlation between the visual acuity ratio and pattern reversal visual evoked potential （PRVEP） P100 waveform amplitude ratio of both eyes. Methods Forty-seven volunteers were selected, and the visual chart visual acuity of both eyes was measured. The visual acuity ratio of the eye with poor vision to the eye with better vision was calculated by five grade notation method. The amplitudes of P100 waveforms of both eyes were recorded respectively by using black-and-white checkerboard PRVEP and chosing 1°, 15' stimulating visual angle, and the ratio of amplitudes between the two eyes was also calculated. SPSS 20.0 software was used to analyze the correlation between the visual acuity ratio and the ratio of P100 waveform amplitudes between the two eyes. Return test and linear regression analysis with the binocular ratio of P100 waveform amplitudes as the independent variable （x） and the binocular visual acuity ratio as the dependent variable （y） were made. Results There was a positive correlation between the binocular visual acuity ratio and the ratio of P100 waveform amplitudes under 15' stimulating visual angle （Pearson correlation coefficient was 0.62, P=0.000）. The fitting linear regression equation was y=0.090 x+0.846 （F=20.954, P=0.000）. There was no significant correlation between the binocular ratio of visual acuity and the binocular ratio of P100 waveform amplitudes under 1° stimulating visual angle （P>0.05）. Results of return test showed that there was no statistical significance in the difference between visual acuity estimated by equation and actual detected visual acuity. Conclusion In forensic appraisal of monocular injury, fitting linear regression equation of binocular visual acuity ratio and the binocular ratio of P100 waveform amplitudes under 15' stimulating visual angle, is helpful for visual acuity level estimation of the injured eye to some extent.

Assessment of the Original Height of L1~2 after Vertebral Compression Fracture

OBJECTIVES

To explore the assessment method of original height of L_1-2 after vertebral compression fracture and its application value in forensic clinical practice.

METHODS

A total of 154 normal thoracic and lumbar X-ray films were collected, and 140 cases were used as experimental group while 14 cases as validation group. The heights of anterior （Ha） and posterior （Hp） vertebral body of T₁₂-L₃ vertebrae in each X-ray image were measured. In the experimental group, the correlation analysis between Ha_L₁ and Ha_T₁₂, Hp_T₁₂, Hp_L₁, Ha_L₂ and Hp_L₂ was carried out, and regression equation was established via fitting. The correlation analysis between Ha_L₂ and Ha_L₁, Hp_L₁, Hp_L₂, Ha_L₃, Hp_L₃ was performed, and the regression equation was also established via fitting. The difference between the predicted and measured values of Ha_L₁ and Ha_L₂ in validation group was compared.

RESULTS

In the 140 normal subjects, Ha_L₁ （y₁） was well correlated with Ha_T₁₂ （x₁） and Ha_L₂（x₂）, and the multiple linear regression equation was y₁=2.545+0.423 x₁+0.486 x₂ （determining coefficient R²=0.712, P<0.05; F=169.206, P<0.05）. There was no significant difference between the predicted and actual measured values of Ha_L₁ in the validation group （ P>0.05）. HaL₂ （y₂） was well correlated with Ha_L₁ （x₃） and Ha_L₃ （x₄）, and the multiple linear regression equation was y₂=4.354+0.530 x₃+0.349 x₄ （determining coefficient R²=0.689, P<0.05; F=151.575, P<0.05）. There was no significant difference between the predicted and actual measured values of Ha_L₂ in the validation group （ P>0.05）.

CONCLUSIONS

It is more appropriate to evaluate the original height of L₁ or L₂ single vertebrae by comparing with the height of the anterior edge of the upper and lower adjacent vertebral bodies.

Enabling liquid vapor analysis using synchrotron VUV single photon ionization mass spectrometry with a microfluidic interface

Vacuum ultraviolet (VUV) single photon ionization mass spectrometry (SPI-MS) is a vacuum-based technique typically used for the analysis of gas phase and solid samples, but not for liquids due to the challenge in introducing volatile liquids in a vacuum. Here we present the first demonstration of in situ liquid analysis by integrating the System for Analysis at the Liquid Vacuum Interface (SALVI) microfluidic reactor into VUV SPI-MS. Four representative volatile organic compound (VOC) solutions were used to illustrate the feasibility of liquid analysis. Our results show the accurate mass identification of the VOC molecules and the reliable determination of appearance energy that is consistent with ionization energy for gaseous species in the literature as reported. This work validates that the vacuum-compatible SALVI microfluidic interface can be utilized at the synchrotron beamline and enable the in situ study of gas-phase molecules evaporating off the surface of a liquid, which holds importance in the study of condensed matter chemistry.

[Contrast Visual Evoked Potentials under Pattern Stimulus in Ocular Trauma]

OBJECTIVES

To study the characteristic of contrast visual evoked potentials （CVEP） in patients with ocular trauma.

METHODS

Sixty patients defined as ocular trauma by forensic clinical examination in our center were selected, and split into 0.2-0.3 （Group A）, 0.3-0.5 （Group B） and ≥0.5 （Group C） according to the best corrected visual acuity. The variation characteristics of wave amplitude and latency of CVEP under 100%, 25% and 10% contrast were observed and analyzed statistically.

RESULTS

（1） Under the same contrast, the wave amplitude of P₁₀₀ decreased with the decrease of stimulus perspective. （2） Under the same stimulus perspective, the wave amplitude of P₁₀₀ decreased with the decrease of contrast （P<0.05）. （3） Under the contrast of 100% and 25% with the same stimulus perspective （except 100% 7' perspective stimulus）, the difference between group A and group B had no statistical significance （P>0.05）. Between group A and group C, group B and group C, the wave amplitude of P₁₀₀ gradually increased with the increase of vision （P<0.05）. Under the contrast of 10% with 15' stimulus perspective, the wave amplitude of P₁₀₀ increased with the increase of vision （P<0.05）. （4） Under the same contrast with the same stimulation perspective, the latency of P₁₀₀ wave shortened with the increase of vision, while the difference had no statistical significance （P>0.05）. Under the same stimulus perspective, the latency of P₁₀₀ wave was prolonged with the decrease of contrast （P>0.05）.

CONCLUSIONS

CVEP may become one of the possible methods for the evaluation of contrast visual acuity.

[Comparison of Measurement Methods of Exophthalmos and Its Forensic Significance]

OBJECTIVES

To compare the differences between Hertel exophthalmometry and CT on exophthalmos measurement, and explore its practical application value in forensic medicine.

METHODS

Fifty-six normal individuals without eye injuries or diseases were selected as the control group. The absolute values of exophthalmos were measured in the standardized CT image workstation. The difference of binocular exophthalmos was compared in normal group. Forty-seven cases with unilateral orbital fracture were divided into injured eye group and normal eye group according to the presence of binocular orbital fractures. The differences of the absolute values of eophthalmos from the same eye and the relative values of eophthalmos between two eyes for same person measured by Hertel exophthalmometry and CT were analyzed.

RESULTS

There was no statistical difference of exophthalmos between the normal eyes measured by CT method. In the normal eye group, the absolute value of exophthalmos measured by CT method was （16.66±5.41） mm, which was （16.16±4.45） mm when measured by the Hertel exophthalmometry method. There was no statistical difference between two groups （P>0.05）. In the injured eye group, there was statistical difference between the absolute values of exophthalmos measured by two measurement methods （ P<0.05）. There was no statistical difference of the relative values of exophthalmos between the injured eyes and the normal eyes by two measurement methods （P>0.05）.

CONCLUSIONS

CT method has a good consistency with Hertel exophthalmometry, which can be applied into the practice of medicolegal expertise.

Effect of tobacco smoke on hydrogen sulfide-induced rat thoracic aorta relaxation

Levels of hydrogen sulfide (H₂S), a gaseous signaling molecule, are reduced in the serum of individuals who smoke. We hypothesized that tobacco smoke influenced smooth muscle relaxation by decreasing H₂S levels and this effect could also influence expression of cystathionine γ-lyase (CSE) and sulfonylurea receptor-2 (SUR-2). The aim of this study was to explore the effect of tobacco smoke on H₂S-mediated rat thoracic aorta relaxation and its possible mechanism. Thirty-two Sprague-Dawley rats were divided into four groups: control (C) group, short-term smoker (SS) group, mid-term smoker (MS) group, and long-term smoker (LS) group. H₂S concentrations in serum, action of H₂S on rat aortic vascular relaxation, and expression of CSE and SUR-2 in thoracic aortic smooth muscle were measured. Although there was no significant difference in H₂S between the C and the SS groups, concentration of H₂S was significantly reduced in both the LS and MS groups compared to control (P<0.01). Furthermore, H₂S was significantly lower in the LS than in the MS group (P<0.05). Rat aortic vascular relaxation was lower in all three treatment groups compared to the control, with the most significant decrease observed in the LS group (P<0.05 compared to the MS group). Expression of CSE and SUR-2 was reduced in the LS and MS groups compared to control (P<0.05), with the lowest levels observed in the LS group (P<0.05). Therefore, tobacco smoke reduced expression of CSE and SUR-2 in rat thoracic aorta, which may inhibit H₂S production and vascular dilation.

Modulating the function of ATP-binding cassette subfamily G member 2 (ABCG2) with inhibitor cabozantinib

Cabozantinib (XL184) is a small molecule tyrosine kinase receptor inhibitor, which targets c-Met and VEGFR2. Cabozantinib has been approved by the Food and Drug Administration to treat advanced medullary thyroid cancer and renal cell carcinoma. In the present study, we evaluated the ability of cabozantinib to modulate the function of the ATP-binding cassette subfamily G member 2 (ABCG2) by sensitizing cells that are resistant to ABCG2 substrate antineoplastic drugs. We used a drug-selected resistant cell line H460/MX20 and three ABCG2 stable transfected cell lines ABCG2-482-R2, ABCG2-482-G2, and ABCG2-482-T7, which overexpress ABCG2. Cabozantinib, at non-toxic concentrations (3 or 5μM), sensitized the ABCG2-overexpressing cells to mitoxantrone, SN-38, and topotecan. Our results indicate that cabozantinib reverses ABCG2-mediated multidrug resistance by antagonizing the drug efflux function of the ABCG2 transporter instead of downregulating its expression. The molecular docking analysis indicates that cabozantinib binds to the drug-binding site of the ABCG2 transporter. Overall, our findings demonstrate that cabozantinib inhibits the ABCG2 transporter function and consequently enhances the effect of the antineoplastic agents that are substrates of ABCG2. Cabozantinib may be a useful agent in anticancer treatment regimens for patients who are resistant to ABCG2 substrate drugs.

Cardiac progenitor cell-derived exosomes prevent cardiomyocytes apoptosis through exosomal miR-21 by targeting PDCD4

Cardiac progenitor cells derived from adult heart have emerged as one of the most promising stem cell types for cardiac protection and repair. Exosomes are known to mediate cell–cell communication by transporting cell-derived proteins and nucleic acids, including various microRNAs (miRNAs). Here we investigated the cardiac progenitor cell (CPC)-derived exosomal miRNAs on protecting myocardium under oxidative stress. Sca1⁺CPCs-derived exosomes were purified from conditional medium, and identified by nanoparticle trafficking analysis (NTA), transmission electron microscopy and western blotting using CD63, CD9 and Alix as markers. Exosomes production was measured by NTA, the result showed that oxidative stress-induced CPCs secrete more exosomes compared with normal condition. Although six apoptosis-related miRNAs could be detected in two different treatment-derived exosomes, only miR-21 was significantly upregulated in oxidative stress-induced exosomes compared with normal exosomes. The same oxidative stress could cause low miR-21 and high cleaved caspase-3 expression in H9C2 cardiac cells. But the cleaved caspase-3 was significantly decreased when miR-21 was overexpressed by transfecting miR-21 mimic. Furthermore, miR-21 mimic or inhibitor transfection and luciferase activity assay confirmed that programmed cell death 4 (PDCD4) was a target gene of miR-21, and miR-21/PDCD4 axis has an important role in anti-apoptotic effect of H9C2 cell. Western blotting and Annexin V/PI results demonstrated that exosomes pre-treated H9C2 exhibited increased miR-21 whereas decreased PDCD4, and had more resistant potential to the apoptosis induced by the oxidative stress, compared with non-treated cells. These findings revealed that CPC-derived exosomal miR-21 had an inhibiting role in the apoptosis pathway through downregulating PDCD4. Restored miR-21/PDCD4 pathway using CPC-derived exosomes could protect myocardial cells against oxidative stress-related apoptosis. Therefore, exosomes could be used as a new therapeutic vehicle for ischemic cardiac disease.

[The effect of phospholipid transfer protein on cigarette smoke extract induced epithelial-mesenchymal transition of rat alveolar type Ⅱ cells]

OBJECTIVE

To investigate the effect of phospholipid transfer protein(PLTP) on cigarette smoke extract(CSE) induced epithelial-mesenchymal transition(EMT) in rat alveolar Type Ⅱ cells (RLE-6TN).

METHODS

CSE of different concentrations (0%, 0.25%, 0.5% and 1%) was co-cultured for 2 or 3 days with RLE-6TN, either pre-treated or not pre-treated with siRNA-PLTP for 6 h. Expression levels of E-cadherin mRNA and Vimentin mRNA were examined by RT-PCR, while expression levels of PLTP, E-cadherin, N-cadherin and Vimentin were examined by Western blot.

RESULTS

Our results showed that the expression of E-cadherin mRNA decreased in CSE-treated groups: 1.01±0.05, 0.74±0.05, 0.65±0.03, 0.30±0.08 respectively at different concentrations of CSE (0 %, 0.25%, 0.5 %, and 1.0%); while the level of Vimentin mRNA increased significantly in 1% CSE treated cells(1.88±0.49), compared with control cells (1.01±0.20). Treatment with CSE at different concentrations (0%, 0.25%, 0.5% and 1%) showed that the protein levels of PLTP were 0.42±0.02, 0.89±0.25, 1.08±0.18, 1.61±0.06 respectively; those of E-cadherin were 1.61±0.04, 1.08±0.10, 0.62±0.08, 0.68±0.17, respectively; those of N-cadherin were 0.60±0.14, 0.57±0.26, 0.88±0.30, 1.94±0.54, respectively; and those of Vimentin were 0.61±0.05, 0.98±0.16, 1.07±0.14, 1.34±0.19, respectively; all P<0.05 when the 1% CSE group was compared with the control group. EMT induced by CSE was significantly inhibited by siRNA-PLTP.

CONCLUSION

PLTP may be involved in CSE induced EMT of rat alveolar cells.

Evaluation of Cellular Antioxidant and Antiproliferative Activities of Five Main Phyllanthus Emblica L. Cultivars in China

The cell-based antioxidant activity assay as more biological relevant assay was considered to be more accurate to predict antioxidant activity in vivo than chemical activity assays. In the present study, the five main Phyllanthus emblica L. cultivars in China were subjected for cellular antioxidant activity based on HepG2 cells as well as antiproliferative activity. Total phenolics, total flavonoids and oxygen radical absorbance capacity were also measured. The results showed that Qingyougan, Binggan and Boligan (832±100, 774±52 and 704±28 μmol of quercetin equivalents/100 g) had higher cellular antioxidant activity than Tianyougan and Yougan (553±50 and 457±24 μmol of quercetin equivalents/100 g) in phosphate buffered saline wash protocol whereas, Boligan (3735±217 μmol of quercetin equivalents/100 g) had the highest cellular antioxidant activity and Tianyougan (2025±171 μmol of quercetin equivalents/100 g) had the lowest cellular antioxidant activity in no phosphate buffered saline wash protocol. The highest and lowest antiproliferative activities were observed in Binggan and Tianyougan (median effective dose: 6.95±0.11 and 14.03±0.10 mg/ml), respectively. The significant correlation was only observed between total flavonoids and cellular antioxidant activity from no phosphate buffered saline wash protocol (R(2) =0.908, P<0.05), and total flavonoids and antiproliferative activity (R(2) =0.887, P<0.05), suggesting the major contribution of flavonoids to the bioactivities of emblica. Overall, the data obtained revealed that different Phyllanthus emblica L. cultivars had strong cellular antioxidant and antiproliferative activities, thus should be recommended to increase consumption for health.

Variants -250G/A and -514C/T in the LIPC gene are associated with hypertensive disorders of pregnancy in Chinese women

We examined the influence of the promoter polymorphisms -250G/A (rs2070895) and -514C/T (rs1800588) in the human hepatic lipase (LIPC) gene on dyslipidemia and hypertensive disorders complicating pregnancy (HDCP) in a Chinese population. Clinically defined HDCP patients (N = 321) and healthy pregnant women (N = 331) were recruited and genotyped using polymerase chain reaction-restriction fragment length polymorphism for the two LIPC single nucleotide polymorphisms (SNPs). The results showed significant relationships between HDCP and triglycerides, apolipoprotein A1, and high-density lipoprotein cholesterol (P < 0.05), which confirmed that HDCP was accompanied by dyslipidemia. The results also demonstrated that in gestational hypertension (GH) patients, both total cholesterol (TC) and systolic blood pressure (SBP) levels were related to the two SNPs (P ≤ 0.004), although no significant association was found between HDCP and LIPC genotypes or alleles. Significant linkage disequilibrium of the two SNPs was found in both HDCP patients (R(2) = 0.867) and controls (R(2) = 0.91). Body mass index (BMI) was associated with -250G/A in women with mild preeclampsia (MPE) (P = 0.01). Carriers of the mutant homozygote -250AA genotype presented higher BMI in the MPE group. In conclusion, the LIPC -250G/A and -514C/T variants influenced TC and SBP levels in GH patients and the BMI level in the MPE group, although there was no evidence to validate an association between HDCP and LIPC allele, genotype, or haplotype frequencies.

Involvement of Src tyrosine kinase and protein kinase C in the expression of macrophage migration inhibitory factor induced by H2O2 in HL-1 mouse cardiac muscle cells

Macrophage migration inhibitory factor (MIF), a pleiotropic cytokine, plays an important role in the pathogenesis of atrial fibrillation; however, the upstream regulation of MIF in atrial myocytes remains unclear. In the present study, we investigated whether and how MIF is regulated in response to the renin-angiotensin system and oxidative stress in atrium myocytes (HL-1 cells). MIF protein and mRNA levels in HL-1 cells were assayed using immunofluorescence, real-time PCR, and Western blot. The result indicated that MIF was expressed in the cytoplasm of HL-1 cells. Hydrogen peroxide (H₂O₂), but not angiotensin II, stimulated MIF expression in HL-1 cells. H₂O₂-induced MIF protein and gene levels increased in a dose-dependent manner and were completely abolished in the presence of catalase. H₂O₂-induced MIF production was completely inhibited by tyrosine kinase inhibitors genistein and PP1, as well as by protein kinase C (PKC) inhibitor GF109203X, suggesting that redox-sensitive MIF production is mediated through tyrosine kinase and PKC-dependent mechanisms in HL-1 cells. These results suggest that MIF is upregulated by HL-1 cells in response to redox stress, probably by the activation of Src and PKC.

A refinement to the liquidus-tracking method for vitreous preservation of articular cartilage

The recent liquidus-tracking method developed by Pegg et al. (2006a), as an alternative pathway to vitrification, achieved reasonable survival of post-thawing chondrocytes in situ. One of the main drawbacks of this method is the long duration of the cryoprotectant addition/removal process. This study was conducted to investigate the possibility of reducing the time by rationalizing the final dimethyl sulfoxide (Me2SO) concentration loaded in tissue before being plunged into liquid nitrogen. Using the differential scanning calorimetric technique, the critical cooling and warming rates for solutions of Me2SO in CPTes2 (a potassium-rich medium, modified slightly from Taylor's original formulation by Pegg et al.) were obtained. The critical cooling and warming rates for 47.5 percent (w/w) solution are < 2.5 degree C per min and < 10 degree C per min, respectively, which could be readily realized for 4 ml solution samples held in polypropylene cryovials as demonstrated by experiments. For articular cartilage, 47.5 percent (w/w) may be recommended as the final concentration of Me2SO loaded in the tissue, which will lead to a time cut of about one-third compared with the original protocol of Pegg et al. (2006a).

Assessing genetic divergence in interspecific hybrids of Aechmea gomosepala and A. recurvata var. recurvata using inflorescence characteristics and sequence-related amplified polymorphism markers

Conventional hybridization and selection techniques have aided the development of new ornamental crop cultivars. However, little information is available on the genetic divergence of bromeliad hybrids. In the present study, we investigated the genetic variability in interspecific hybrids of Aechmea gomosepala and A. recurvata var. recurvata using inflorescence characteristics and sequence-related amplified polymorphism (SRAP) markers. The morphological analysis showed that the putative hybrids were intermediate between both parental species with respect to inflorescence characteristics. The 16 SRAP primer combinations yield 265 bands, among which 154 (57.72%) were polymorphic. The genetic similarity was an average of 0.59 and ranged from 0.21 to 0.87, indicating moderate genetic divergence among the hybrids. The unweighted pair group method with arithmetic average (UPGMA)-based cluster analysis distinguished the hybrids from their parents with a genetic distance coefficient of 0.54. The cophenetic correlation was 0.93, indicating a good fit between the dendrogram and the original distance matrix. The two-dimensional plot from the principal coordinate analysis showed that the hybrids were intermediately dispersed between both parents, corresponding to the results of the UPGMA cluster and the morphological analysis. These results suggest that SRAP markers could help to identify breeders, characterize F(1) hybrids of bromeliads at an early stage, and expedite genetic improvement of bromeliad cultivars.

Loss of macrophage migration inhibitory factor impairs the growth properties of human HeLa cervical cancer cells

OBJECTIVES

  This study aims to determine the role of macrophage migration inhibitory factor (MIF), a proinflammatory cytokine associated with cell proliferation and tumour growth in vivo.

MATERIALS AND METHODS

  Our team used RNA interference technology to knock down MIF expression in human HeLa cervical cancer cells and to establish a stable cell line lacking MIF function.

RESULTS

  Our results showed that long-term loss of MIF had little effect on cell morphology, but significantly inhibited their population growth and proliferation. The HeLa MIF-knockdown cells retained normal apoptotic signalling pathways in response to TNF-alpha treatment; however, they exhibited unique DNA profiles following doxorubicin treatment, suggesting that MIF may regulate a cell cycle checkpoint upon DNA damage. Our data also showed that knockdown of MIF expression in HeLa cells led to increased cell adhesion and therefore impaired their migratory capacity. More importantly, cells lacking MIF failed to either proliferate in soft agar or form tumours in vivo, when administered to nude mice.

CONCLUSION

  MIF plays a pivotal role in proliferation and tumourigenesis of human HeLa cervical carcinoma cells, and may represent a promising therapeutic target for cancer intervention.

Comparison of approaches for efficient gene silencing induced by microRNA-based short hairpin RNA and indicator gene expression

MicroRNA-based short hairpin RNAs (shRNAs) are natural inducers of RNA interference and have been increasingly used in shRNA expression strategies. In the present study, we compared the efficiencies of exogenous green fluorescence protein (GFP) and endogenous glyceraldehyde-3-phosphate dehydrogenase (GAPDH) knockdown and red fluorescent protein (RFP) indicator expression mediated by three differently designed plasmids. RFP was introduced either at the 5' end, at the 3' end of the human mir155-based target gene (TG) (e.g., GFP or GAPDH) shRNA expression cassette (EC), or at the 3' end of the chimeric intron-containing TG shRNA EC. Comparisons with the control vector showed an obvious reduction of GFP or GAPDH expression with the various shRNA expression plasmids (P < 0.05). When RFP was located at the 5' end or at the 3' end of the TG shRNA EC, RFP expression was low; whereas when RFP was connected with the chimeric intron-containing TG shRNA EC, RFP expression was high. Taken together, this study demonstrated an efficient plasmid design for both TG silencing induced by microRNA-based shRNA and indicator gene expression in vitro.

High-efficiency direct-pumped Nd:YVO4 laser operating at 1.34 microm

We report a high-efficiency Nd:YVO(4) laser operating at 1342 nm pumped by an all-solid-state Q-switched Ti:Sapphire laser at 879 nm. A plano-concave cavity was optimized to obtain high efficiency and good beam quality. Output power for two Nd:YVO(4) crystals with 1.0- and 3.0- at.% Nd(3+) doping under 879-nm pumping was measured respectively. Comparative results obtained by traditional pumping at 808 nm into the highly absorbing (4)F(5/2) level were presented, showing that the slope efficiency of the 1.0-at.% Nd:YVO(4) laser under 879-nm pumping was 10.5% higher than that of 808-nm pumping. In a 4-mm-thick, 1.0-at.% Nd:YVO(4)4 crystal, a high slope efficiency of 64% was achieved under 879-nm pumping, with an optical-to-optical conversion efficiency of 41.3%.

Generation of 3.5W high efficiency blue-violet laser by intracavity frequency-doubling of an all-solid-state tunable Ti:sapphire laser

In this paper, we report a high power, high efficiency blue-violet laser obtained by intracavity frequency-doubling of an all-solid-state Q-switched tunable Ti:sapphire laser, which was pumped by a 532 nm intracavity frequency-doubled Nd:YAG laser. A beta-BaB2O4 (BBO) crystal was used for frequency-doubling of the Ti:sapphire laser and a V-shape folded three-mirror cavity was optimized to obtain high power high efficiency second harmonic generation (SHG). At an incident pump power of 22 W, the tunable output from 355 nm to 475 nm was achieved, involving the maximum average output of 3.5 W at 400 nm with an optical conversion efficiency of 16% from the 532 nm pump laser to the blue-violet output. The beam quality factor M(2) was measured to be Mx(2)=2.15, My(2)=2.38 for characterizing the tunable blue laser.

Esmolol inhibits Na+ current in rat ventricular myocytes

Esmolol is a unique cardioselective, intravenous, ultra-short acting, beta1-adrenergic blocking agent. It has been widely applied in treating ventricular and supraventricular arrhythmias, especially in emergency situations. In this study the effects of esmolol on sodium current (I(Na)) were investigated by the whole cell patch-clamp recording technique in isolated adult rat ventricular myocytes. The results indicated that esmolol reversibly inhibited I(Na) in a concentration-dependent manner, with an IC50 of 74.2 +/- 0.60 micromol l(-1) with a Hill coefficient of 1.02 +/- 0.04. This inhibition was voltage- and frequency-dependent. Esmolol decreased the peak of the I-V relationship curve at -35 mV from 16.97 +/- 1.68 pA/pF to 6.96 +/- 0.51 pA/pF. The steady-state inactivation curve of I(Na) was shifted to more negative potentials, the voltage at half-inactivation changing from -78.75 +/- 2.3 mV in control to -85.94 +/- 3.2 mV in the presence of esmolol. The development of resting inactivation from closed states was accelerated by esmolol, the time constant was shortened from 62.75 +/- 3.21 ms to 24.93 +/- 2.43 ms, whereas the activation curve was not altered. I(Na) from inactivation could not be recovered completely in the presence of esmolol. These results suggest that esmolol inhibits I(Na) through sodium channel in rat ventricular myocytes by mechanisms involving preferential interaction with the inactivated state and acceleration of the development of inactivation directly from resting state. Therefore, the effect of inhibitory sodium of esmolol may play a vital role in its antiarrhythmic efficacy.

A series of quinoline analogues as potent inhibitors of C. albicans prolyl tRNA synthetase

A series of quinoline inhibitors of C. albicans prolyl tRNA synthetase was identified. The most potent analogue, 2-(4-bromo-phenyl)-6-chloro-8-methyl-4-quinolinecarboxylic acid, showed IC50 = 5 nM (Ca. ProRS) with high selectivity over the human enzyme.

[Preparation of novel magnetic dextran affinity adsorbents and their application to purify urokinase]

The reverse phase suspension and embedment technique were adopted to prepare magnetic dextran microsphere (MDMS). The dispersion medium was mixture of some organic solvents. Span-80 was used as stabilizer. The aqueous dextran with magnetic fluid was suspended in dispersion medium with epichlorohydrin as cross-linking reagent. The mixture was stirred for 30 minutes at room temperature and then heated at 70 degrees C for 4 hours, MDMS was thus obtained. MDMS was activated by epichlorohydrin on which 6-aminohexanoic acid, glycine or ethylene diamine was bonded as spacers. Then it was coupled with p-aminobenzamide, L-arginine methyl ester or guanidohexanoic acid and five magnetic affinity adsorbents were prepared. The MDMS was polydisperse particles with the size of 50-300 meshes and the content of Fe3O4 was about 6.2 per cent in the MDMS. Influence of some parameters such as viscosity and density of organic phase, the volume ratio of organic and aqueous phase, the quantity of surfactant and stirring speed on preparing MDMS was studied. Magnetic affinity adsorbents were used to purify crude urokinase in a bath mode and the effect of coupling reagents and ligands on results of purification was discussed. The bioactivity recovery was 40.0 to 60.7 per cent, the purification-fold was between 14.9 and 32.8, and the adsorptive capacity varies from 89 mg to 121 mg per milliliter of adsorbent.

De novo expression of macrophage migration inhibitory factor in atherogenesis in rabbits

Macrophage migration inhibitory factor (MIF) has been shown to play an important role in macrophage-mediated diseases. We investigate the potential role of MIF in atherogenesis using a hypercholesterolemic rabbit model. New Zealand White rabbits fed with a 2% cholesterol diet developed hypercholesterolemia and early fatty streaks at 1 month. The lesions became advanced at 3 months and were associated with de novo MIF expression by vascular endothelial cells (VECs) and smooth muscle cells (SMCs), as demonstrated by immunohistochemistry, reverse transcriptase-polymerase chain reaction, and in situ hybridization. By contrast, there was no increase in MIF levels in rabbits fed a normal diet. In early atherogenesis, marked upregulation of MIF mRNA and protein by VECs and some intimal cells were closely associated with CD68(+) monocyte adhesion onto and subsequent migration into subendothelial space. Of significance, the accumulation of macrophages was exclusively localized to areas of strong MIF expression, which may be associated with the macrophage-rich fatty streak lesion formation. Upregulation of MIF by SMCs is transient during atherogenesis. Importantly, strong MIF expression by activated macrophages may be responsible for the development of foam cell-rich lesions. Finally, the ability of MIF to induce intercellular adhesion molecule-1 expression by VECs implicates its pathogenic role in atherogenesis. In conclusion, the present study provides the first demonstration that MIF is markedly upregulated during atherogenesis. Upregulation of MIF by VECs and SMCs may play a role in macrophage adhesion, transendothelial migration, accumulation, and, importantly, transformation into foam cells. Furthermore, strong MIF expression by macrophages may both initiate and amplify the atherogenesis process.

[Detection of GLO I phenotypes in blood and blood stains using agarose starch gel electrophoretic analysis]

The distribution of GLO I phenotypes was studied using mixed agarose starch gel electrophoresis in 234 Chinese Han population in Changsha area. Three GLO I phenotypes were detected. The gene frequencies were as follows: GLO I1 = 0.1303 and GLO I2 = 0.8697. The phenotype frequencies of GLO I were compared not only among the different nationalities but with those reported by other countries. Both the 20 bloodstain samples kept at room temperature for 40 days and the other 20 bloodstain samples kept at 4 degrees C for at least 100 days could be correctly phenotyped. Two out of 8 watered bloodstains, their GLO I2-1 phenotype was changed to GLO I2-2. In blind trial, 15 bloodstain samples kept at room temperature for 40 days could be phenotyped correctly.

Coherent acoustic phonon oscillations in semiconductor multiple quantum wells with piezoelectric fields

Large coherent acoustic phonon oscillations were demonstrated using InGaN/GaN multiple quantum wells with piezoelectric fields. With UV femtosecond pulse excitation, photogenerated carriers screened the piezoelectric field and initiated the displacive coherent phonon oscillations. The specific phonon frequency was selected by the coupling between the periodic carrier distribution and the corresponding acoustic phonon mode. The induced acoustic phonon oscillation resulted in piezoelectric field modulation and then caused absorption variation through the quantum confined Franz-Keldysh effect. The wave vector uncertainty due to the finite sample width was found to determine the observed dephasing time.

Pharmacokinetics of atenolol enantiomers in 12 Chinese healthy men

AIM

To study the pharmacokinetics of atenolol (Ate) stereoisomers in Chinese.

METHOD

A single oral dose of 100 mg of racemic Ate tablets were given to 12 healthy volunteers of Han nationality. Plasma and urine concentrations were determined by the reversed phase HPLC method.

RESULTS

The disposition of d-Ate and l-Ate was conformed to one-compartment model. Maximal plasma concentration (Cmax): l-Ate (331 +/- 79) micrograms.L-1, d-Ate (342 +/- 78) micrograms.L-1. Area under blood concentration-time curve (AUC): d-Ate (2635 +/- 610) micrograms.h.L-1, l-Ate (2442 +/- 588) micrograms.h.L-1. Renal clearance (Clr): l-Ate (6.9 +/- 1.2) L.h-1, d-Ate (6.5 +/- 1.3) L.h-1.

CONCLUSION

The disposition of Ate stereoisomers is of stereoselectivity.

Synthesis and structure-activity relationships of a series of novel thiazoles as inhibitors of aminoacyl-tRNA synthetases

A series of novel aminoacyl adenylate mimics has been prepared and evaluated for their inhibitory activity against aminoacyl-tRNA synthetases. Several of these thiazole derivatives displayed potent and selective enzyme activity against both Gram-positive and Gram-negative bacteria.

Positional candidate gene approach and functional genomics strategy in atopy gene discovery

As part of our effort in searching for genetic factors contributing to the susceptibility to atopy and asthma, we have focused on a 'positional candidate' approach in identifying CC chemokine gene polymorphisms and their functional correlates. To date, a single-nucleotide polymorphism was found in the RANTES proximal promoter region, and a high degree of sequence variation was identified in the 3'-untranslated region -of the eotaxin gene. Also, we are pursuing a series of functional genomics' studies designed to identify differentially expressed genes in a panel of allergen-specific human Th2 cells and in antigen-induced hyperreactive murine airways. This is performed using a combination of protocols including suppression-subtractive hybridization and cDNA array hybridizations with 18,363 nonredundant sequences. A data base is being generated from a list of subtracted cDNA sequences and array-positive clones to categorize differentially expressed genes. Sequences are being placed in biologically relevant categories on the basis of function (i.e., receptor, signal transduction pathways, transcription, and translation). With the increasing amount of sequence information compiled by the Human Genome Project, it will be particularly challenging to integrate functional gene-mapping efforts to define and compare aberrant genotypes/phenotypes in atopic diseases.

Antisense oligodeoxynucleotides downregulated c-sis mRNA expression to inhibit proliferation of vascular smooth muscle cells

AIM

To assess the inhibitory effect of c-sis antisense oligodeoxynucleotides (ODN) on vascular smooth muscle cells (VSMC) proliferation and c-sis proto-oncogene mRNA expression.

METHODS

The VSMC were cultured with Dulbecco's modified Engle's medium (DMEM) containing synthesized c-sis antisense or sense oligomers, [3H]thymidine (TdR) incorporation into DNA was determined by liquid scintillation counter and the numbers of cells were counted by cell counting plate, the mRNA level was observed by using of reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

C-sis antisense ODN 2, 4, 6, 8, and 10 mumol.L-1 inhibited VSMC proliferation (10.3% +/- 0.7%, 22.6% +/- 0.9%, 31.0% +/- 1.1%, 35.4% +/- 0.9%, and 43.3% +/- 1.2%) and [3H]TdR incorporation (6.8% +/- 0.3%, 9.7% +/- 0.7%, 29.0% +/- 0.6%, 32.0% +/- 0.7%, and 50.6% +/- 1.3%) in a concentration-dependent manner. When VSMC were treated with antisense ODN 10 mumol.L-1 for 4 d, the highest inhibitory rate of VSMC growth and that of [3H]TdR incorporation were 60.3% +/- 1.0% and 56.3% +/- 0.9%, respectively. RT-PCR showed that c-sis proto-oncogene antisense ODN downregulated c-sis mRNA expression obviously, while c-sis sense ODN did not inhibit VSMC proliferation and expression of c-sis proto-oncogene mRNA.

CONCLUSION

The c-sis antisense ODN inhibited VSMC proliferation and downregulated c-sis mRNA level.

Protective effect of substance P on permeability of airway epithelial cells in culture

Although substance P (SP) has been shown to mediate microvascular leakage in response to various stimuli, some data suggest that, in contrast, SP may play a protective role in the maintenance of airway epithelial integrity. To investigate the effect of SP on epithelial barrier function, we measured paracellular mannitol flux and the transepithelial potential difference (PD) of human bronchial epithelial (HBE) and canine bronchial epithelial (CBE) cells. Incubation of confluent cell cultures with SP had no effect on baseline flux. However, pretreatment inhibited the flux-enhancing effects of 0.5 ppm ozone by 50% in HBE cells and 40% in CBE cells and inhibited the ozone-induced decrease in PD in CBE cells by 54%. SP-afforded protection was reduced by the neurokinin (NK)-1 receptor antagonist CP-96,345.NK1 and NK3 receptor agonists also inhibited ozone-induced permeability, whereas an NK2 receptor agonist was without significant effect. These data indicate that SP exerts a protective effect on bronchial epithelial barrier function under conditions of challenge, which appears to be mediated in large part through NK1 receptors.

Expression of ICAM-1 in airway epithelium after acute ozone exposure in the mouse

We investigated the time course and regional distribution of the expression of intercellular adhesion molecule-1 (ICAM-1) on airway epithelial cells and the polymorphonuclear leukocyte (PMN) inflammatory response in the lung after acute exposure to ozone (O3). C57BL/6J mice were exposed to air or 2 ppm O3 for 3 h and killed immediately or 3, 6, 9, or 21 h after exposure. Expression of ICAM-1 was examined by immunohistochemical staining of frozen sections. PMN influx was evaluated by lavage and by histochemical staining of myeloperoxidase (MPO) and measurement of tissue MPO activity. ICAM-1 expression exhibited regional selectivity and temporal patterns that were unique to each region. Upregulation of ICAM-1 expression on the epithelial cells in the trachea, and to a lesser extent in the lobar and segmental bronchi, was observed 3-9 h after exposure and remained present at 21 h. Enhanced ICAM-1 expression in bronchioles and terminal bronchiole/alveolar duct regions was evident earlier (immediately to 3 h after exposure) but returned to baseline levels by 21 and 9 h, respectively. Maximal ICAM-1 expression and PMN influx in the lung parenchyma were concurrently observed at 3 h, followed by transepithelial migration of PMNs to the airway lumen. These results demonstrate regional variations in airway inflammatory activity and are supportive of the notion that upregulation of ICAM-1 on the airway epithelium may play a role in local regulation of PMN influx to the airways after acute O3 exposure.

Specific binding of endothelin-1 to canine tracheal epithelial cells in culture

We have studied the binding of endothelin-1 (ET-1) to cultured canine tracheal epithelial cells. A single specific binding site for 125I-labeled ET-1 was identified with an apparent dissociation constant (Kd) of 0.2 nM, maximal binding sites (Bmax) of 6.7 x 10(3) sites/cell, and half-maximal inhibition (IC50) of 0.3 nM during a 2-h incubation period. The binding of 125I-ET-1 to these cells was inhibited by the presence of unlabeled ET-1, ET-2, or BQ-123, whereas ET-3 and sarafotoxin S6c did not compete for this binding site. These binding characteristics are consistent with those of the ETA receptor. At 37 degrees C, specific binding continuously increased over 18 h, while at 4 degrees C, it reached a plateau by 2 h. The increase in binding at 37 degrees C was not associated with DNA synthesis but was dependent upon protein synthesis, suggesting that epithelial binding sites were produced continuously under these incubation conditions. Our results indicate that canine tracheal epithelial cells possess specific binding sites for ET-1 with characteristics similar to those of the ETA receptor subtype. Because these cells are demonstrated to both release and bind ET-1, the results further suggest that ET-1 is involved in paracrine and/or autocrine control mechanisms in the airway epithelium.