[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 (CA_19-9) 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 CA_19-9 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 (CA_19-9) 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 CA_19-9. (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.

Identification of the Fosl1/AMPK/autophagy axis involved in apoptotic and inflammatory effects following spinal cord injury

Strategies for reducing spinal cord injury (SCI) have become a research focus because an effective treatment of SCI is unavailable. The objective of this study was to explore the underlying mechanisms of Fosl1 following SCI. Based on the analysis of the Gene Expression Omnibus (GEO) database, Fosl1 was found to be highly enhanced in SCI. This result was confirmed in our animal model, and Fosl1 was found to be obviously expressed in neurons. Next, we treated PC-12 cells with H₂O₂ to mimic injured neurons and further verified that Fosl1 silencing upregulated AMPK expression, promoted autophagy and inhibited inflammation and apoptosis. Subsequently, a special inhibitor of AMPK was used to examine the role of AMPK, and we learned that the inhibition of AMPK suppressed autophagy and promoted inflammation and apoptosis following Fosl1 silencing. These changes completely reversed the beneficial effects of Fosl1 silencing on injured PC-12 cells. Moreover, treatment with an AMPK activator resulted in effects that were opposite those of the inhibitor. Finally, rats were injected intrathecally with si-Fosl1 to detect its role in vivo. The results showed that si-Fosl1 improved neurological function and decreased apoptosis and inflammation at 14 d postoperation, and the activator further benefited the rats of si-Fosl1 treatment. In conclusion, Fosl1 inhibits autophagy and promotes inflammation and apoptosis through the AMPK signaling pathway following SCI in vivo and in vitro.

[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.

Bioinformatics-based study to identify immune infiltration and inflammatory-related hub genes as biomarkers for the treatment of rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic autoimmune disease whose principal pathological change is aggressive chronic synovial inflammation; however, the specific etiology and pathogenesis have not been fully elucidated. We downloaded the synovial tissue gene expression profiles of four human knees from the Gene Expression Omnibus database, analyzed the differentially expressed genes in the normal and RA groups, and assessed their enrichment in functions and pathways using bioinformatics methods and the STRING online database to establish protein-protein interaction networks. Cytoscape software was used to obtain 10 hub genes; receiver operating characteristic (ROC) curves were calculated for each hub gene and differential expression analysis of the two groups of hub genes. The CIBERSORT algorithm was used to impute immune infiltration. We identified the signaling pathways that play important roles in RA and 10 hub genes: Ccr1, Ccr2, Ccr5, Ccr7, Cxcl5, Cxcl6, Cxcl13, Ccl13, Adcy2, and Pnoc. The diagnostic value of these 10 hub genes for RA was confirmed using ROC curves and expression analysis. Adcy2, Cxcl13, and Ccr5 are strongly associated with RA development. The study also revealed that the differential infiltration profile of different inflammatory immune cells in the synovial tissue of RA is an extremely critical factor in RA progression. This study may contribute to the understanding of signaling pathways and biological processes associated with RA and the role of inflammatory immune infiltration in the pathogenesis of RA. In addition, this study shows that Adcy2, Cxcl13, and Ccr5 have the potential to be biomarkers for RA treatment.

Identification of Regeneration and Hub Genes and Pathways at Different Time Points after Spinal Cord Injury

Spinal cord injury (SCI) is a neurological injury that can cause neuronal loss around the lesion site and leads to locomotive and sensory deficits. However, the underlying molecular mechanisms remain unclear. This study aimed to verify differential gene time-course expression in SCI and provide new insights for gene-level studies. We downloaded two rat expression profiles (GSE464 and GSE45006) from the Gene Expression Omnibus database, including 1 day, 3 days, 7 days, and 14 days post-SCI, along with thoracic spinal cord data for analysis. At each time point, gene integration was performed using "batch normalization." The raw data were standardized, and differentially expressed genes at the different time points versus the control were analyzed by Gene Ontology enrichment analysis, the Kyoto Encyclopedia of Genes and Genomes pathway analysis, and gene set enrichment analysis. A protein-protein interaction network was then built and visualized. In addition, ten hub genes were identified at each time point. Among them, Gnb5, Gng8, Agt, Gnai1, and Psap lack correlation studies in SCI and deserve further investigation. Finally, we screened and analyzed genes for tissue repair, reconstruction, and regeneration and found that Anxa1, Snap25, and Spp1 were closely related to repair and regeneration after SCI. In conclusion, hub genes, signaling pathways, and regeneration genes involved in secondary SCI were identified in our study. These results may be useful for understanding SCI-related biological processes and the development of targeted intervention strategies.

[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.

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.

High-throughput sample preparation procedures for the quantitation of a new bone integrin ανβ3 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.

[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.

[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.

[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.

Hyperselective posterior rhizotomy in treatment of spasticity of paralytic limbs

One hundred and eight patients with spasticity of the paralytic limbs were treated successfully with hyperselective posterior rhizotomy (SPR). Of the 108 patients, 100 had cerebral palsy, 2 hemiplegia, 3 sequelae of cerebral injury, 2 paraplegia and 1 multiple sclerosis. Twelve patients received cervical SPR and 96 lumbosacral SPR. Laminectomy is performed to open the dura and to separate the posterior spinal root into several rootlets. The lower threshold rootlets were divided after electrical stimulation. Follow-up for 6 to 30 months showed that the effective rate of reducing spasticity was over 95% and functional improvement rate over 80%.

[Regulation of riboflavin biosynthesis in Salmonella typhimurium]

7 independent rib genes fusions with MudJ (lacZ, Kanr) were isolated by transposon MudJ mutagenesis in Salmonella typhimurium. 5 of them are blue on the X-gal plate, and the beta-galactosidase activity of the cells grown in E medium containing various concentration of riboflavin were assayed. The results showed that the expression of rib gene are not repressed by riboflavin. It appears to be synthesized constitutively in Salmonella typhimurium.

Phosphate groups as substrate determinants for casein kinase I action

Phosphorylation of rabbit muscle glycogen synthase by cyclic AMP-dependent protein kinase has been shown to enhance subsequent phosphorylation by casein kinase I (Flotow, H., and Roach, P. J. (1989) J. Biol. Chem. 264, 9126-9128). In the present study, synthetic peptides based on the sequences of the four phosphorylated regions in muscle glycogen synthase were used to probe the role of substrate phosphorylation in casein kinase I action. With all four peptides, prior phosphorylation significantly stimulated phosphorylation by casein kinase I. A series of peptides was synthesized based on the NH2-terminal glycogen synthase sequence PLSRTLS7VSS10LPGL, in which phosphorylation at Ser7 is required for modification of Ser10 by casein kinase I. The spacing between the P-Ser and the acceptor Ser was varied to have 1, 2, or 3 intervening residues. The peptide with a 2-residue spacing (-S(P)-X-X-S-) was by far the best casein kinase I substrate. When the P-Ser residue at Ser7 was replaced with P-Thr, the resulting peptide was still a casein kinase I substrate. However, substitution of Asp or Glu residues at Ser7 led to peptides that were not phosphorylated by casein kinase I. Phosphorylation of one of the other peptides showed that Thr could also be the phosphate acceptor. From these results, we propose that there are substrates for casein kinase I for which prior phosphorylation is a critical determinant of protein kinase action. In these instances, an important recognition motif for casein kinase I appears to be -S(P)/T(P)-Xn-S/T- with n = 2 much more effective than n = 1 or n = 3. Thus, casein kinase I may be involved in hierarchal substrate phosphorylation schemes in which its activity is controlled by the phosphorylation state of its substrates.

[Transpon Tn5 mutagenesis in Citrobacter]

When E. coli 1830/PJB4JI mating with four Citrobacter strains all were Kanamycin resistant, but a majority of KanrGens transconjugants were obtained from C-3-1. Among 3000 KanrGens 21 were auxotrophs, these are Lys-(1), Ura-(1), Arg-(2), Iso-(2), His-(2), Met-(1), Phe-(1), Tyr-(1), Ser-(1), Thr-(1), Leu-(3), Pro-(1), Ade-(3), Lac-(1), PJB4JI plasmid DNA were detected in parent strain E. coli 1830, but not in auxotrophs strains which carrying Tn5 induced mutations. Twenty auxotrophs chromosome DNA were hybridized with Tn5 DNA labeled with 32P respectively, all auxotrophs has positive reaction. Therefore, we concluded from genetic and physical data that auxotrophs resulted from Tn5 transposition from PJB4JI into C-3-1 chromosome.