[Characteristics of SPECT/CT-derived pulmonary perfusion imaging in chronic pulmonary vascular stenosis with different etiologies].

Objective: To explore the characteristics of pulmonary blood flow perfusion imaging of single photo emission computer tomography/computer tomography (SPECT/CT) in chronic pulmonary vascular Stenosis (CPVS) caused by different etiological factors. Methods: This is a retropective study. Present study screened 50 consecutive cases diagnosed with chronic pulmonary vascular stenosis from January 2019 to January 2020 in the department of cardiology of Gansu Provincial Hospital and underwent SPECT/CT pulmonary blood flow perfusion examination. Thirteen patients were excluded because of pulmonary vascular lesions with a disease course of less than 3 months and poor image quality. According to the etiology, patients were divided into fibrosing mediastinitis (FM) group, Takyasu's arteritis (PTA) group, and chronic thromboembolic pulmonary hypertension/chronic thromboembolic pulmonary disease (CTEPH/CTED) group. The severity of pulmonary blood flow perfusion was evaluated in accordance with the Begic scoring principle in the three groups. The overall Begic score, lung lobe scores among three groups were compared. CT signs of lung SPECT/CT, such as enlargement of hilar lymph node, atelectasis, bronchial stenosis, were also analyzed in three groups. Results: A total of 37 patients with chronic pulmonary vascular stenosis were finally enrolled (18 in the FM group, 5 in the PTA group, and 14 in the CTEPH/CTED group). The total Begic score of pulmonary perfusions was similar among the three groups (F=0.657,P>0.05). There was a statistically significant difference in the left upper lobe Begic score among the three groups (H=4.081, P<0.05). The left upper lobe Begic score was higher in the FM group than in the PTA group (3.44±2.50 vs. 1.60±0.55, P<0.05). As compared to other two groups, patients in FM group were featured with CT signs of higher percent of hilar enlargement (FM group vs. PTA group: 16/18 vs. 1/5, P=0.008; FM group vs. CTEPH/CTED group: 16/18 vs. 3/14, P=0.000 2), enlargement of the pulmonary hilum lymph nodes (FM group vs. PTA group: 14/18 vs. 1/5, P=0.033; FM group vs. CTEPH/CTED group: 14/18 vs. 2/14, P=0.001), and calcification of mediastinal soft tissue (FM group vs. PTA group: 11/18 to 0/5, P=0.037; FM group vs. CTEPH/CTED group: 11/18 vs. 1/14, P=0.003). The proportion of CT signs of bronchial stenosis (9/18 vs. 0/14, P=0.002) and atelectasis (9/18 vs. 1/14, P=0.002) was also higher in the FM group than in the CTEPH/CTED group. In case of abnormal pulmonary blood flow perfusion, the diagnostic accuracy of CT signs hilar enlargement, hilar lymph node enlargement, mediastinal soft tissue calcification, bronchial stenosis, and atelectasis for the diagnosis of FM were 81.1%, 83.8%, 78.4%, 75.7%, and 73.0%, respectively. Conclusion: There is no significant difference in the Begic score of SPECT/CT pulmonary blood flow perfusion imagines among the three groups of patients. Impaired pulmonary blood flow perfusion combined with typical CT signs is useful for identifying patients with FM.

[The sleep condition and its association with cognitive function of the elderly in six provinces of China].

Objective: To analyze the association between sleep duration and cognitive function of the elderly in six provinces of China. Methods: Based on the cross-sectional survey data of the elderly from the Healthy Ageing Assessment Cohort Study in 2019, 4 644 participants' sociodemographic and economic indicators, lifestyle, prevalence of major chronic diseases, and sleep status, including night-time sleep duration, daytime sleep duration and insomnia, were collected by questionnaires. Cognitive function was evaluated by the Mini-Mental State Examination. Multivariate logistic regression was used to analyze the association between night-time sleep duration, daytime sleep duration and cognitive function. Results: The mean age of 4 644 respondents was (72.3±5.7) years, and 2 111 of them were males (45.5%). The mean total daily sleep time of the elderly was (7.9±1.9) hours, and the proportion of those who slept less than 7.0, 7.0-8.9 and≥9.0 hours was 24.1% (1 119), 42.1% (1 954) and 33.8% (1 571), respectively. The mean sleep time at night was (6.9±1.7) hours. About 23.7% (1 102) of the elderly did not sleep during the day, and the mean duration of the elderly who slept during the day was (78±51) minutes. Among the elderly with insomnia, 47.9% were still satisfied with their sleep quality. The mean value of MMSE score of 4 644 respondents was (24.5±5.3), and the cognitive impairment rate was 28.3% (1 316). The results of multivariate logistic regression model analysis showed that the OR (95%CI) value of the risk of cognitive impairment in older people who did not sleep, slept for 31 to 60 minutes and slept more than one hour was 1.473 (1.139 to 1.904), 1.277 (1.001 to 1.629) and 1.496 (1.160 to 1.928), respectively, compared with those who slept for 1 to 30 minutes during the daytime. Compared with those who slept for 7.0‒8.9 hours at night, the OR (95%CI) value of the risk of cognitive impairment in older people who slept more than 9.0 hours was 1.239 (1.011 to 1.519). Conclusion: The cognitive function is related to sleep duration in the Chinese elderly.

[Efficacy of dienogest versus gonadotropin-releasing hormone agonist combined with dienogest sequential therapy in the treatment of adenomyosis].

Objective: To investigate the efficacy and safety of dienogest (DNG) alone and gonadotropin-releasing hormone agonist (GnRH-a) combined with DNG sequential treatment to adenomyosis. Methods: The clinical data of 110 patients with adenomyosis attending the First Affiliated Hospital of Nanjing Medical University from December 2019 to March 2022 were retrospectively analyzed, including 40 patients treated with DNG (2 mg/day) alone (DNG group) and 70 patients treated with sequential DNG (2 mg/day) after 3-6 injections of GnRH-a (GnRH-a+DNG group). The clinical data before and after treatment were compared between the two groups. Results: (1) The dysmenorrhea visual analogue scale (VAS) scores, cancer antigen 125 (CA125) and cancer antigen 19-9 (CA19-9) levels at different time periods after treatment were significantly lower than before treatment in both groups (median before treatment: DNG group 70.0 mm, 68.55 kU/L, 22.45 kU/L respectively, GnRH-a+DNG group 80.0 mm, 151.50 kU/L, 20.44 kU/L respectively; all P<0.001). (2) The hemoglobin (Hb) levels of patients in both groups at different time periods after treatment were significantly higher than those before treatment (median: DNG group 102.00 g/L, GnRH-a+DNG group 94.00 g/L; all P<0.001). (3) Treatment with DNG alone did not have a significant effect on uterine volume in patients of DNG group (P>0.05), and uterine volume decreased significantly in the 15th-24th months of GnRH-a+DNG group compared with that before treatment (median: 167.76 vs 227.77 cm3; P<0.05). (4) There were no significant differences in hepatic and renal function and coagulation indexes between the two groups before and after treatment (all P>0.05), and no significant abnormal lesions were observed in breast tissue during the follow-up period. (5) The incidence of amenorrhea of GnRH-a+DNG group was higher than that of DNG group, and the incidences of irregular spotting bleeding and breakthrough hemorrhage were lower than those in DNG group. Conclusions: Whether DNG is used alone or in combination with GnRH-a in sequence, it could significantly relieve dysmenorrhea symptoms, improve the level of Hb, reduce the levels of CA125 and CA19-9 in patients with adenomyosis, with no adverse effects on coagulation and hepatic or renal function. GnRH-a sequential DNG therapy is superior to DNG alone in improving uterine bleeding patterns and controlling the growth of uterine volume in patients with adenomyosis.

[Changes of coagulation function in patients with adenomyosis].

Objective: To explore the different coagulation state in patients with adenomyosis and its clinical significance. Methods: Clinical data of the patients admitted to the First Affiliated Hospital of Nanjing Medical University from January 2017 to December 2021 were retrospectively analyzed. (1) Differential coagulation state between 25 healthy women and 25 patients with adenomyosis were compared during menstrual and non-menstrual periods. (2) The coagulation indexes of 145 patients with adenomyosis (observation group 1) and 129 patients with cervical intraepithelial neoplasia grade Ⅲ (control group 1) who underwent hysterectomy in non-menstrual period were compared. (3) The coagulation indexes of 154 patients with adenomyosis (observation group 2) and 147 women without myometrial lesions (control group 2) who underwent endometrial curettage during uterine bleeding period were compared. (4) Correlations of coagulation index with cancer antigen 125 (CA125), cancer antigen 19-9 (CA19-9) and uterine volume in patients with adenomyosis were analyzed. Results: (1) The coagulation state of each health women during the menstrual and non-menstrual period showed no significant differences (all P>0.05). For the 25 patients with adenomyosis, fibrinogen [FIB; 2.61 g/L(2.50-3.10 g/L)] and D-dimer [0.60 mg/L (0.40-1.00 mg/L)] in the menstrual period were significantly higher than those in the non-menstrual period [2.25 g/L (1.90-2.70 g/L) and 0.27 mg/L (0.20-0.40 mg/L), respectively; both P<0.01], while thrombin time [TT; 16.70 s (16.10-17.40 s)] in the menstrual period was significantly lower than that in the non-menstrual period [17.95 s (17.20-18.40 s); P<0.01]. (2) In the non-bleeding period, D-dimer [0.26 mg/L (0.20-0.40 mg/L)] and platelet count [257.0×109/L (212.0×109/L-308.5×109/L)] of observation group 1 were significantly higher than those of control group 1 (all P<0.01). Besides, FIB (r=0.237, P=0.004) and D-dimer (r=0.373, P<0.001) were positively correlated with CA125, while prothrombin time (PT; r=-0.208, P=0.012) and internationalized normalized ratio of plasma prothrombin time (PT-INR; r=-0.201, P=0.015) were negatively correlated with CA19-9. (3) In the bleeding period, PT [10.70 s (10.10-11.20 s)] and PT-INR [0.93 (0.90-1.00)] of observation group 2 were significantly lower than those of control group 2 (all P<0.01), while D-dimer [0.41 mg/L (0.20-0.80 mg/L)] was significantly higher than that in the control group 2 (P<0.001). Furthermore, FIB (r=0.252, P=0.038) and D-dimer (r=0.321, P=0.008) were positively correlated with uterine volume, while activated partial thromboplastin time (APTT; r=-0.190, P=0.018) and TT (r=-0.304, P=0.012) were negatively correlated with uterine volume. (4) During non-menstrual period and uterine bleeding period, APTT and TT in patients of observation group 1 and 2 combined with anemia were significantly lower than those of non-anemia patients (all P<0.05). Conclusion: Patients with adenomyosis have a tendency to hypercoagulability in both the uterine bleeding and non-bleeding periods, which may be related to enlarged uterine volume, increased serum CA125 and anemia.

[Short-term efficacy and perioperative safety of catheter-based intervention for pulmonary vein stenosis caused by fibrosing mediastinitis].

Objective: To evaluate the short-term efficacy and perioperative safety of catheter-based intervention in patients with pulmonary vein stenosis caused by fibrosing mediastinitis (FM). Methods: It was a case series study. Consecutive patients with pulmonary vein stenosis caused by FM, who underwent percutaneous pulmonary vein angioplasty in Gansu Provincial Hospital from January 2018 to June 2020, were retrospective enrolled. The baseline characteristics, comorbidities, exercise capacity and hemodynamic data before and after treatment were compared, and the procedural related complications were evaluated. Results: A total of 30 patients ((64.3±7.1) years, 15 males) were included. Sixty-three pulmonary vein stenosis were treated by 32 percutaneous pulmonary vein angioplasty procedures. Forty-four stents were implanted in 41 pulmonary veins after balloon angioplasty, and the diameter of implanted stents was (8.3±1.2)mm. Balloon angioplasty was performed on 22 pulmonary vein stenosis, the mean balloon diameter was (4.2±2.1)mm. The pulmonary vein diameter increased from (2.6±1.3) to (6.6±2.6) mm (P<0.001) and the pressure gradient across the pulmonary vein stenotic segment reduced from 19 (12, 29) to 2 (0, 4) mmHg (1 mmHg=0.133 kPa) (P<0.001) immediately post procedure. The pulmonary vein flow grade was significantly improved compared with baseline (P<0.001). The most common operation related complications were lung injury (44.0% (11/25)) and hemoptysis (18.8% (6/32)), which did not need special treatment. During the 2.0 (1.3, 3.2) months follow-up, the WHO functional class was significantly improved (P<0.05), the 6-minute walking distance increased from (254.8±114.5) m to (342.8±72.4)m (P<0.05), the mean pulmonary arterial pressure decreased from (40.9±8.3) mmHg to (35.4±7.7) mmHg (P<0.01), 17 out of 19 patients with refractory pleural effusion experienced total remission during the follow-up period (P<0.001). CT pulmonary venography was repeated in 17 patients. The incidence of in-stent restenosis of pulmonary vein was 24.0% (6/25). Conclusions: Percutaneous pulmonary vein angioplasty is effective for the treatment of pulmonary vein stenosis caused by fibrosing mediastinitis. However, it's not so safe, procedural related complication should be paid attention to and the rate of in-stent restenosis is relative high during the short-term follow-up.

MiR-200b-5p inhibits proliferation of ovarian cancer cells by targeting ATAD2 and regulating PI3K/AKT signaling pathway.

OBJECTIVE: The purpose of this study was to investigate the influences of micro ribonucleic acid (miR)-200b-5p on proliferation and apoptosis of ovarian cancer (OC) cells, and to explore its correlations with the target gene ATPase family, AAA domain containing 2 (ATAD2), and the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. MATERIALS AND METHODS: Human ovarian fibroblasts (HOFs) or human OC cell lines (A2780) were cultured in vitro, and then, A2780 cells were separately transfected with miR-200b mimics or miR-NC or cultured with ATAD2-specific inhibitor BAY-850. Thereafter, the expression levels of miR-200b and ATAD2 messenger RNA (mRNA) were measured via qRT-PCR, and the proliferative capacity of cells was detected by CCK-8 assay. Next, the cell apoptosis was determined by means of flow cytometry and one-step TUNEL assay. Finally, the targeted regulatory relationship between miR-200b and ATAD2 was examined using a Luciferase reporter assay system, and the protein expressions were detected through Western blot (WB) assay. RESULTS: It was found that the expression level of miR-200b was remarkably lower (p<0.05), while the mRNA expression level of ATAD2 was notably higher (p<0.05) in A2780 cells than those in HOFs. The transfection with miR-200b mimics markedly reduced the mRNA expression level of ATAD2 (p<0.05) and the proliferative capacity (p<0.05) and increased the apoptosis rate (p<0.05) of A2780 cells. Besides, it was detected via the Luciferase reporter assay system that miR-200b inhibited ATAD2. BAY-850 significantly decreased the expression level of ATAD2 protein (p<0.05) and the proliferative capacity (p<0.05) but improved the apoptosis rate (p<0.05) of cells. Moreover, both miR-200b mimics and BAY-850 could distinctly repress the protein expression levels of PI3K and p-Akt of the PI3K/Akt signaling pathway (p<0.05) and enhance the expression of suppressor gene p53 (p<0.05). CONCLUSIONS: MiR-200b-5p can inhibit the proliferation and promote the apoptosis of OC cells through targeted inhibition of ATAD2 expression and regulation of the PI3K/Akt signaling pathway.

Downregulation of lncRNA CCHE1 inhibits cell proliferation, migration and invasion by suppressing MEK/ERK/c-MYC pathway in nasopharyngeal carcinoma.

OBJECTIVE: The current study was designed to investigate the functionality of lncRNA CCHE1 in nasopharyngeal carcinoma. MATERIALS AND METHODS: MiRNA levels of lncRNA CCHE1 were examined by RT-qPCR. CCK8 assay and colony formation assay were together performed to detect cell proliferation viability. Furthermore, wound healing assay and transwell assay were respectively conducted to assess cell migration and invasion. In addition, proteins related to MEK/ERK/c-MYC pathway were detected by Western blot. RESULTS: Elevated levels of CCHE1 were verified in NPC cell lines. Downregulation of CCHE1 significantly inhibited tumor growth and suppressed A549 cell proliferation, migration and invasion. MEK/ERK/c-MYC pathway was activated in nasopharyngeal carcinoma. Treatment of PD98059 (MEK inhibitor) or SCH772984 (ERK inhibitor) reversed the effects of CCHE1 on cell proliferation, migration and invasion in NPC. CONCLUSIONS: The present study suggested that downregulation of lncRNA CCHE1 could inhibit cell proliferation, migration and invasion by suppressing MEK/ERK/c-MYC pathway in nasopharyngeal carcinoma.

[Blood-borne occupation exposures in dental practice of medical staff: status and protection].

Objective: To understand the status of blood-borne occupational exposure and protection among health care workers (HCWs) in dental practice, and provide evidence for making effective prevention. Methods: From April 1 to 15, 2019, a stratified random sampling method was conducted to investigate the data of blood-borne occupational exposure among 221 dental HCWs in 2018, and Chi-squared Test was used to evaluate the differences of status on occupational exposure and protection among different professionals, such as nurses, doctors and trainees, and among different-grade hospitals. Results: A total of 166 HCWs were exposed to occupational exposure 269 times, with the annual incidence of 75.11% (166/221) , and 37.55% (101/269) of exposures were reported. However, all source patients of exposures had failed to be traced. 89.59% (241/269) of exposures were sharp injuries. The top three instruments caused injuries were syringe/bilan needles, suture needles and vehicle needles, accounting for 35.68% (86/241) 、16.60% (40/241) and 16.18% (39/241) , respectively; and the top three exposure operations were removal/disposal of needles or instruments, suture/assisting suture and injection of anesthetic, accounting for 37.17% (100/269) 、22.30% (60/269) and 17.84% (48/269) , respectively. There were statistically significant differences among different professionals in occupational exposure frequency, reporting rate, the types of instruments caused injuries, exposure operations and hepatitis B vaccinated time (P<0.01) . The compliance rate of standard precautions, safe operation, post-exposure reporting and prevention, and training on occupational protection were generally poor among HCWs, with significant differences in different-grade hospitals (P<0.01) . Conclusion: There is a high incidence, low reporting rate and poor self-protection of blood-borne occupational exposure among dental HCWs. Strongly suggesting that standard precautions, safe use and disposal of oral instruments, active post-exposure report and prevention must be improved for everyone.

Evaluation of Dietary Palygorskite Supplementation on Growth Performance, Mineral Accumulations, Antioxidant Capacities, and Meat Quality of Broilers Fed Lead-Contaminated Diet.

The objective of this study was to evaluate influence of dietary palygorskite (Pal) supplementation on growth performance, mineral accumulations in the tissues (livers, kidneys, and muscles), antioxidant capacities, and meat quality of broilers fed lead (Pb)-contaminated diet. One-hundred forty-four male broiler chicks were randomly divided into three treatment groups, receiving a corn-soybean meal basal diet (the control group), the basal diet contaminated with 10 mg/kg Pb (the Pb group), and the basal diet with 10-g/kg Pal supplementation and 10-mg/kg Pb contamination (the Pal/Pb group) from 1 to 42 days of age, respectively. Treatments did not affect growth performance of broilers in the 42-day study (P > 0.05). Compared with the control group, Pb contamination increased Pb accumulation in the livers, kidneys, and muscles (P < 0.05); elevated malondialdehyde accumulation in the livers, kidneys, and breast muscles; glutathione peroxidase activity in the livers and superoxide dismutase activity in the kidneys (P < 0.05); exacerbated drip loss in the pectoralis muscles (P < 0.05); and reduced glutathione peroxidase activity in the pectoralis muscles (P < 0.05) of broilers at 42 days of age. The values of these parameters were reversed in the Pal/Pb group to levels comparable with those in the control group (P < 0.05). Additionally, Pal supplementation reduced redness value in the pectoralis muscles (P < 0.05), and decreased Cu concentration in the pectoralis muscles and livers at 42 days of age as well as its accumulation in the kidneys at both 21 and 42 days of age compared with the other two groups (P < 0.05). The results suggested that dietary Pal supplementation would decrease Pb residue in the tissues, alleviate oxidative stress, and affect meat quality of broilers exposed to Pb.

Urban Fringe Land Use Transitions in Hong Kong: From New Towns to New Development Areas.

Land in urban fringe area is the primary source for land supply and development. In Hong Kong (HK), nine new towns have been built in New Territories since 1970s, providing 172.6 km2 built-up land and large amount of residences for 3.4 million people. However, due to land scarcity, development restriction, and social opposition, New Development Area (NDA), as the small-scale extension of New Town (NT), was designated as one of the main approaches for HK medium and long term land supply. To demonstrate the characteristics of urban fringe land use transitions in Hong Kong, literature review and case study were used in this research. The history of new town development and the scheme of new development areas were introduced firstly. Afterwards, the land use features of NT and NDA were compared and the case of Hung Shui Kiu NDA was illustrated. It is concluded that while housing, infrastructure and facility were the main elements in NTs, employment, vibrancy and environment were suggested to be the new compulsory elements in NDAs integrated to the traditional planning concepts. As for the development approach, lease modification was adopted in NDA to allow private landowners directly develop their land, in addition to the traditional development approach of land resumption in NT. It is suggested to ensure the development of NDA, the proposed development plan should be persuasive to provide the optimal land use distribution as a trade-off among the profits of developers, the interests of local villager, government concern and the provision of land for future residents. Also, community engagement will play a more important role in NDA planning process. Referring to the analysis of urban fringe land use transitions and strategies for planning and development, the study would also be helpful to others growing cities.

Preclinical evaluation of a mercaptobenzamide and its prodrug for NCp7-targeted inhibition of human immunodeficiency virus.

Although the effective use of highly active antiretroviral therapy results in the suppression of virus production in infected individuals, it does not eliminate the infection and low level virus production in cells harboring virus in sanctuary sites. Thus, the continued search for new antiretroviral agents with unique and different mechanisms of HIV inhibition remains critical, and compounds that can reduce the level of virus production from cells already infected with HIV, as opposed to preventing de novo infection, would be of great benefit. A mercaptobenzamide (MDH-1-38) and its prodrug (NS1040) are being developed as potential therapeutic compounds targeting the zinc finger of HIV nucleocapsid. In the presence of esterase enzymes, NS1040 is designed to be converted to MDH-1-38 which has antiviral activity. While we presume that NS1040 is rapidly converted to MDH-1-38 in all experiments, the two compounds were tested side-by-side to determine whether the presence of a prodrug affects the antiviral activity or mechanism of action. The two compounds were evaluated against a panel of HIV-1 clinical isolates in human PBMCs and monocyte-macrophages and yielded EC50 values ranging from 0.7 to 13 µM with no toxicity up to 100 µM. MDH-1-38 and NS1040 remained equally active in human PBMCs in the presence of added serum proteins as well as against HIV-1 isolates resistant to reverse transcriptase, integrase or protease inhibitors. Cell-based and biochemical mechanism of antiviral action assays demonstrated MDH-1-38 and NS1040 were virucidal at concentrations of 15 and 50 µM, respectively. Cell to cell transmission of HIV in multiple passages was significantly reduced in CEM-SS and human PBMCs by reducing progeny virus infectivity at compound concentrations greater than 2 µM. The combination of either MDH-1-38 or NS1040 with other FDA-approved HIV drugs yielded additive to synergistic antiviral interactions with no evidence of antiviral antagonism or synergistic toxicity. Serial dose escalation was used in attempts to select for HIV strains resistant to MDH-1-38 and NS1040. Virus at several passages failed to replicate in cells treated at increased compound concentrations, which is consistent with the proposed mechanism of action of the virus inactivating compounds. Through 14 passages, resistance to the compounds has not been achieved. Most HIV inhibitors with mechanism of antiviral action targeting a viral protein would have selected for a drug resistant virus within 14 passages. These studies indicate that these NCp7-targeted compounds represent new potent anti-HIV drug candidates which could be effectively used in combination with all approved anti-HIV drugs.

Fast numerical method for electromagnetic scattering from an object above a large-scale layered rough surface at large incident angle: vertical polarization.

A fast numerical method has been proposed in this paper for calculating the electromagnetic scattering from a perfectly electric conducting object above a two-layered dielectric rough surface. The focus in this study is large incidence. The parallel fast multipole method is combined with the method of moments for fast implementation of the scattering from this composite model. The biconjugate gradient method is adopted to solve the unsymmetrical matrix equation and parallelized. The simulating time and parallel speedup ratio with different processors are provided. Several numerical results are shown and analyzed to discuss the influences of the parameters of the rough surface, the object, and the intermediate medium on the bistatic scattering.

High-throughput sample preparation procedures for the quantitation of a new bone integrin alpha(nu)beta(3) antagonist in human plasma and urine using liquid chromatography-tandem mass spectrometry.

High throughput LC-MS/MS assays to quantitate a new alpha(nu)beta(3) bone integrin antagonist (I) in human plasma and urine have been developed using instruments programmed to automate sample preparation procedures. Packard liquid handling system-MultiPROBE II EX was programmed for preparing calibration standards in control plasma and urine, acidifying all standards, quality control (QC), and clinical samples with necessary dilutions, and adding the internal standard to the acidified samples. TOMTEC Quadra 96 was programmed to perform the solid phase extraction (SPE) process on a 3M 96-well mixed phase cation standard density (MPC-SD) plate to isolate the analytes from the sample matrix. The extract collected from both types of matrices was directly injected into reversed-phase LC-MS/MS system with a Turbo Ion Spray (TIS) interface in the positive ionization mode. The plasma and urine assays have the calibration range of 0.5-1500 and 2-6000 ng/mL, respectively. Validation of the automated and the manual plasma assays showed that application of MultiPROBE II to sample preparation gave comparable accuracy and precision. Overall, the automated approaches with minimum manual intervention enhanced the throughput of sample preparation.

Determination of a beta(3)-agonist in human plasma by LC/MS/MS with semi-automated 48-well diatomaceous earth plate.

Methods for the determination of a beta(3)-agonist (A) in human plasma were developed and compared based on high-performance liquid chromatography (HPLC) with tandem mass spectrometric (MS/MS) detection using a turbo ion spray (TIS) interface. Drug and internal standard were isolated from plasma by three sample preparation methods, liquid-liquid extraction, Chem Elut cartridges and 48-well diatomaceous earth plates, that successively improved sample throughput for LC/MS/MS. MS/MS detection was performed on a PE Sciex API 365 tandem mass spectrometer operated in positive ion mode and using multiple reaction monitoring (MRM). The precursor/product ion combinations of m/z 625/607 and 653/515 were used to quantify A and internal standard, respectively, after chromatographic separation of the analytes. Using liquid-liquid extraction and Chem Elut cartridges, the assay concentration range was 0.5-100 ng/ml. Using diatomaceous earth plates, the concentration range of the assay was extended to 0.5-200 ng/ml. For all three assays, the statistics for precision and accuracy is comparable. The assay accuracy ranged from 91-107% and intraday precision as measured by the coefficient of variation (CV) ranged 2-10%. The sample throughput was tripled when the diatomaceous earth plate method was compared with the original liquid-liquid extraction method.

Diagnostic yield of repeated smear microscopy examinations among patients suspected of pulmonary TB in Shandong province of China.

OBJECTIVES: To analyse the yield of five repeated smear microscopy examinations for the diagnosis of smear-positive pulmonary tuberculosis (TB). METHODS: Patients with respiratory symptoms and abnormal chest X-rays provided five spontaneous sputum samples for acid-fast bacilli (AFB) smear microscopy in one of nine county laboratories. RESULTS: Of 9302 patients with respiratory symptoms and abnormal X-rays, 6437 (69%) had at least one smear-positive sputum. Of these, 84.5% were diagnosed on the first smear, 96.7% on the first two smears, and 99.9% on the first three sputum smears. The fourth and fifth sputum smears yielded only seven additional cases (0.1%). CONCLUSIONS: Smear microscopy examination of two spontaneous sputum specimens is the most efficient, and three sputum smear examinations provide a diagnosis in almost all cases.

[Regulation of purine biosynthetic genes expression in Salmonella typhimurium].

To study binding funtion of 4 consensus bases in 16 bp PUR box with purR protein, the directed site mutation for each was carried out, which mutate from C to G, A to G, A to G, T to C, respectively. Gel retardation showed that the PUR box carrying a reserved mutation could not bind with purR protein. It suggested that all these consensus base pairs are necessary to hold the normal binding function of PUR box with purR protein.

[Studies of gene regulation of de novo biosynthetic pathway of purine in Salmonella typhimurium. X. Isolation of purR(am) mutants and preliminary studies of amino acid substitution].

Starting from a super-repressed mutant of purR, 3-18, 439 independent candidates of purR- mutants were isolated by using NCE selecting plate with lactose as sole carbon source. Among these mutants. 11 amber mutants were detected by introducing a tRNA suppressor gene. Cotransduction analysis proved that the amber mutation sites of 11 amber mutants all located on purR. Amino acid substitution experiments were performed with three tRNA suppressors, supD, supE and supF, for each purR(am). The results showed that the same amino acid substitution occurred in different site of PurR protein could result in varied effects on purR function; different amino acid substitution occurred at the same position of PurR protein also could produced varied effects on purR function.

[Studies on non-anthraquinones in Rheum officinale Baill].

OBJECTIVE: To investigate the non-anthraquinones from the root and rootstock of Rheum officinale. METHOD: The chemical constituents were obtained from the 85% alcohol extract of the radix and rhizoma of R. officinale by column chromatography and identified by spectroscopic analysis. RESULT: Ten non-anthraquinones were obtained, of which eight were identified by spectroscopic analysis as rheosmine, daucosterol, d-catechin, 6-cinnamoylisolindleyin, (-)-epicatechin-3-O-gallate, resveratrol-4'-O-beta-D-(6"-O-galloyl)-glucopyranoside, gallic acid, D-sorbitol. CONCLUSION: Compounds rheosmine and D-sorbitol were obtained from the genus Rheum for the first time.

[Expression regulation of purine biosynthetic genes in Salmonella typhimurium. VI. Isolation and characterization of super-repressor mutants].

Starting from strain of Salmonella typhimurium purD::lac, 86 exponential cultures were mutagenized with NTG and white or light blue clones on E + ado + Xgal plate were selected as candidates of purRs mutant. Total 66 independent candidate strains were obtained. By assaying their beta-galactosidase activity under the repressed and derepressed conditions, determining their frequency of revertional mutation, Conducting transductional analysis of mutational site and dorminance test, 11 candidates strains were proved to be super-repressor mutants. These mutants are useful for studying the expression of purine biosynthetic gene and relationship between protein structure and function in general.