Incidence, Predictors, and Strategies for Retrograde Wire Tracking Failure via Poor Septal Collateral Channels in Chronic Total Occlusion.

Background: Retrograde guidewire (GW) tracking success via a poor septal collateral channel (CC) when an antegrade approach fails is crucial for successful revascularization of coronary chronic total occlusion (CTO) with poor septal CC. However, the incidence, predictors, and management strategies for retrograde GW tracking failure via poor septal CC remain unclear. Methods: In total, 122 CTO patients who underwent retrograde septal percutaneous coronary intervention (PCI) with poor CC between January 2017 and May 2022 were retrospectively analyzed. Patients were divided into the retrograde GW tracking success group (success group) and the retrograde GW tracking failure group (failure group). Clinical and angiographic data were compared to investigate the predictors of retrograde GW tracking failure. Results: The incidence of GW tracking failure was 22.1% (27/122). Patients in the failure group had a higher prevalence of left anterior descending artery (LAD) CTO (66.7% vs 37.9%; p = 0.009) and a higher incidence of well-developed non-septal collateral (66.7% vs 30.5%; p = 0.001). Patients with a septal CC diameter ≥ 1 mm (48.1% vs 70.5%; p = 0.040), ≥ 3 septal CCs (44.4% vs 66.3%; p = 0.046), and initial retrograde application of Guidezilla (37.0% vs 60.0%; p = 0.048) were significantly lower in the failure group than in the success group. The binary logistics regression model showed that a CC diameter < 1 mm, well-developed non-septal collateral, and LAD CTO were independent predictors for GW tracking failure in patients undergoing retrograde CTO PCI via poor septal CC. Conclusion: The success rate of retrograde GW tracking via poor septal CC was high, with a relatively high procedural success rate. A CC diameter < 1 mm, well-developed non-septal collateral, and LAD CTO were independent predictors of GW tracking failure in patients undergoing retrograde CTO PCI via poor septal CC.

Association between triglyceride glucose index and adverse clinical outcomes in patients with acute myocardial infarction and LDL-C≤1.8 mmol/L who underwent percutaneous coronary intervention: a prospective cohort study.

Background: Recently, the triglyceride glucose (TyG) index has emerged as a reliable predictive indicator for adverse outcomes of cardiovascular disease. However, the roles of the TyG index in patients with acute myocardial infarction (AMI) and low-density lipoprotein cholesterol (LDL-C)≤1.8 mmol/L after percutaneous coronary intervention (PCI) remain unclear. Methods: A total of 599 patients diagnosed with AMI and LDL-C ≤ 1.8 mmol/L at the 1-month follow-up after PCI were consecutively enrolled between January 2017 and January 2020. The patients were subsequently divided into three groups based on tertiles of the TyG index. The parameters, including the TyG index, were compared to explore the risk factors associated with major adverse cardiovascular and cerebrovascular events (MACCEs) during the 1-year follow-up. Results: Sixty-nine patients (11.5%) with 90 MACCEs were recorded during the 1-year follow up, including 13 patients (8.6%) in the Tertile 1 group, 36 (12.0%) in the Tertile 2 group, and 20 (13.4%) in the Tertile 3 group. Patients with a higher TyG index had a significantly increased incidence of MACCEs compared to those with a lower TyG index (22.1% vs. 14.0% vs. 9.9%, p=0.010). Kaplan-Meier analysis demonstrated that patients with a higher TyG index had a significantly lower probability of survival without MACCEs. Furthermore, a binary logistic regression model indicated that the TyG index was the only independent predictor for MACCEs in these patients. Conclusion: A higher TyG index was associated with a higher incidence of MACCEs in patients with AMI and well-controlled LDL-C levels after PCI. This suggests that the TyG index can serve as a predictive indicator for adverse cardiovascular outcomes in these patients.

Innovation of Platform Economy Business Model Driven by BP Neural Network and Artificial Intelligence Technology.

In order to enhance the competitiveness of enterprises, how to evaluate and enhance the competitiveness of B2B e-commerce enterprises and promote the orderly and healthy development of B2B e-commerce industry are discussed. This paper puts forward the research on the innovation of platform economic business model driven by BP neural network and artificial intelligence technology. BP neural network is used to study and evaluate the competitiveness of B2B e-commerce companies. According to the B2B e-commerce company competitiveness theory and BP neural network algorithm, combined with BP neural network and B2B e-commerce company competitiveness evaluation index system, a BP neural network model is designed to analyze the competitiveness of B2B e-commerce enterprises. Determine the expected value of network samples, select G1 method to determine the subjective weight, and select entropy weight method to determine the objective weight. With the help of the function in the MATLAB neural network toolbox, the neural network is trained. The results show that when the training times reach 3297 times, the sample mean square error is 9.9869e - 06, and the training network reaches convergence. The samples of three enterprises test the trained neural network and input the data of three test samples into the trained BP neural network, and the output results are 0.1531, 0.1371, and 0.1557, respectively. The network model constructed in this paper is effectively close to the training samples. The established BP neural network has good performance and can be used to evaluate the competitiveness of B2B e-commerce companies. Accelerate technological change and realize innovation. Technological capability is the inexhaustible driving force for the development of enterprises. Only with the innovation of keeping pace with the times can application-oriented e-commerce enterprises meet the needs of customers and the market, form the difference between goods or services, and then enable enterprises to win more customers and market share.

Programmable Pump for Intrathecal Morphine Delivery to Cisterna Magna: Clinical Implications in Novel Management of Refractory Pain Above Middle Thoracic Vertebrae Level Utilizing a Prospective Trial Protocol and Review.

BACKGROUND: The cisterna Intrathecal Drug Delivery system (IDDS) with morphine has proven to be effective in treating refractory cancer pain above the middle thoracic vertebrae level in some countries. However, it has not been fully investigated in others. We designed the current project to investigate the efficacy and safety of cisterna IDDS for pain relief in refractory pain above the middle thoracic vertebrae level in advanced cancer patients. METHODS: This study protocol allows for eligible cancer patients to receive the cisterna IDDS operation. Pain intensity (Visual Analogue scale, VAS), quality of life (36-Item Short-Form Health Survey, SF-36), and depression (Self-Rating Depression scale, SDS) are assessed along with side effects in the postoperative follow-up visits. Recent literature suggests a potential role for cisterna IDDS morphine delivery for refractory pain states above the middle thoracic level. CONCLUSION: The results of this study may provide further evidence that cisterna IDDS of morphine can serve as an effective and safe pain relief strategy for refractory pain above the middle thoracic vertebrae level in advanced cancer patients.

Revascularization of Coronary Artery Chronic Total Occlusion by Active Antegrade Reverse Wire Technique.

OBJECTIVES: To assess the effectiveness and safety of ARW for vascular recanalization in CTO patients. BACKGROUND: Chronic total occlusion (CTO) of coronary artery accompanied with large branch distal to the occluded segment (<2 mm) is one of the challenges physicians are facing during the coronary intervention. In cases where the antegrade wire passed the occluded segment reaching the branch vessel, but could not access the main vessel through various adjustments, application of active antegrade reverse wire technique (ARW) could be considered. Patients and Methods. A total of 301 consecutive CTO patients who received the antegrade percutaneous coronary intervention (PCI) between December 2015 and December 2019 at our institution were included, of whom 11 were treated with ARW (10 successfully) for vascular recanalization. The applicability and safety of ARW were assessed. RESULTS: Among the 301 CTO patients who received antegrade vascular recanalization, 11 were treated with ARW. ARW was successful in 10 patients as follows: from the diagonal branch (D) to anterior descending branch (LAD) in 4 patients; from the septal branch (S) to LAD in 1 patient; from D to S and LAD in 1 patient; from the circumflex branch (LCX) to obtuse marginal branch (OM) in 1 patient; from OM to LCX in 1 patient; from a posterior descending artery (PDA) to the posterior lateral vein (PLV) in 2 patients. Yet, ARW in patient with RCAm CTO failed, while the consequent retrograde PCI succeeded. The mean J-CTO score of the 11 patients was 2.7 ± 0.65, among whom eight were accompanied with calcifications. Sion Black and Fielder XTR reverse wires were used in 9 and 2 patients, respectively. No loss of side branches or severe procedure-related complications occurred in 11 patients. CONCLUSION: Therefore, ARW can improve procedural efficiency and should be popularized for further application.

Incidence, Predictors, and Strategies for Failure of Retrograde Microcatheter Tracking After Successful Wiring of Septal Collateral Channels in Chronic Total Occlusions.

BACKGROUND: Retrograde microcatheter collateral channel (CC) tracking after successful wiring of septal CC is crucial for retrograde revascularization of coronary chronic total occlusion (CTO). However, the incidence, predictors, and strategies for failure of retrograde microcatheter CC tracking after successful wiring of septal CC remain unclear. METHODS: In total, 298 patients with CTO who underwent retrograde septal CC PCI between January 2015 and May 2019 were retrospectively analyzed. Clinical data were compared to investigate the predictors of initial microcatheter tracking failure. RESULTS: The initial and final microcatheter tracking success rates were 79.2% (236/298) and 96.6% (288/298), respectively. The procedural success rate was 94.0% (280/298). The right coronary artery-to-left anterior descending artery septal ratio (48.4% vs 33.1%, p=0.037) and CC tortuosity (34.6% vs 20.8%, p=0.045) were significantly higher in the initial microcatheter CC tracking failure group than in the successful tracking group. Multivariate logistic regression analysis revealed that severe collateral tortuosity (odds ratio [OR]: 13.241, 95% confidence interval [CI]: 3.429-27.057, p=0.038), CC entry angle of <90° (OR:4.921, 95% CI: 1.128-9.997, p=0.002), CC exit angle of <90° (OR:5.037, 95% CI: 2.237-11.182, p=0.004), use of Finecross MG as initial microcatheter (OR:1.826, 95% CI: 1.127-3.067, p=0.035), and shunning initial retrograde application of Guidezilla (OR:0.321, 95% CI: 0.267-0.915, p=0.024) were variables independently associated with initial microcatheter CC tracking failure in patients with CTO undergoing retrograde septal CC PCI. CONCLUSION: The overall initial microcatheter CC tracking failure was 20.8%. Severecollateral tortuosity, CC entry, and exit angle of <90°, use of Finecross MG as initial microcatheter, and shunning initial retrograde application of Guidezilla were variables independently associated with initial microcatheter CC tracking failure in patients with CTO undergoing retrograde septal PCI.

Active Retrograde Extra Backup with a Mother-and-Child Catheter to Facilitate Retrograde Microcatheter Collateral Channel Tracking in Recanalization of Coronary Chronic Total Occlusion.

OBJECTIVE: To explore the feasibility and safety of the active retrograde backup (ARB) for treatment of chronic total occlusion (CTO) during retrograde percutaneous coronary intervention (PCI). BACKGROUND: Guiding support plays an important role in guidewire and microcatheter coronary channel (CC) tracking in retrograde PCI therapy for patients with CTO. However, the feasibility and safety of retrograde active use of a mother-and-child catheter are still unclear. Patients and Methods. A total of 271 consecutive patients with CTO who underwent retrograde PCI between January 2015 and January 2020 were retrospectively analyzed. Clinical data of two groups were compared to evaluate the feasibility and safety of ARB. RESULTS: Of the 271 patients, 69.0% (187/271) underwent therapy through the septal branch, 31.0% (84/271) through the epicardial collateral channel, and 47.6% (129/271) through active retrograde extra backup with a mother-and-child catheter to facilitate retrograde microcatheter collateral CC tracking. The time of wire CC tracking was shorter in the ARB group than that in the non-ARB group (25.4 ± 8.5 vs 26.4 ± 9.7, p=0.348), but there was no significant difference. The duration of the retrograde microcatheter tracking (10.2 ± 3.8 vs 15.5 ± 6.8, p=0.012) and the retrograde approach (62.8 ± 20.3 vs 70.4 ± 24.3, p=0.026) in the ARB group was significantly shorter than that in the non-ARB group. The radiation dose (223.6 ± 112.7 vs. 295.2 ± 129.3, p=0.028), fluoroscopy time (50.6 ± 21.3 vs 62.3 ± 32.1, p=0.030), and contrast volume (301.8 ± 146.7 vs 352.2 ± 179.5, p=0.032) in the ARB group were significantly lower than that in the non-ARB group. There were no life-threatening procedural complications in either group. Complications unrelated to ARB included two cases of donor-vessel dissection, one case of CC perforation, and two cases of target-vessel perforation. There was no statistically significant difference in major adverse cardiac and cerebrovascular events between the groups during hospitalization (p > 0.05). CONCLUSION: ARB is feasible, safe, and conducive to guidewire and microcatheter CC tracking in the recanalization of coronary CTO. It improves procedural efficiency and is worthy of further promotion.

Gender Disparities in Clinical Outcome After Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy in the Chinese Han Population: A Cohort Study.

BACKGROUND: Sex differences in the long-term prognosis of symptomatic hypertrophic obstructive cardiomyopathy (HOCM) patients undergoing alcohol septal ablation (ASA) remain unclear, especially in the Chinese Han population. METHOD: This cohort study included 320 HOCM Chinese Han patients who underwent ASA because of symptomatic left ventricular outflow tract (LVOT) obstruction. Patients were grouped according to sex: females (mean±standard deviation age [SD] 50.7±6.8 years) and males (mean±SD age 52.6±7.3 years). Individuals were followed over the long term. RESULTS: Pre-procedure, women had more symptoms (New York Heart Association [NYHA] class III-IV 67.3% vs 56.3%, p=0.03), more atrial fibrillation (23.5% vs 14.6%, p=0.047) than men. Transient complete atrioventricular block after ASA was more common in woman than in men (34.0 vs 23.4%; p=0.048). Residual LVOT gradient, post-procedural residual left ventricular wall thickness, NYHA functional class, and adverse arrhythmic events were comparable between the two groups. The 10-year survival rate (77% vs 89%, p=0.037) and the annual adverse arrhythmic event rate (1.3% vs 0.4%, p<0.01) following ASA were significantly worse in women compared with men. Kaplan-Meier analysis showed a significantly lower survival in women compared with men (p=0.023). In multivariable modelling, female sex remained independently associated with higher all-cause mortality (hazard ratio, 1.12; 95% confidence interval, 1.08-1.27; p=0.03) when adjusted for age, NYHA class III-IV symptoms, and other cardiovascular comorbidities. CONCLUSIONS: Female patients with HOCM undergoing ASA tended to have more severe symptoms and adverse arrhythmic events. The 10-year survival rate after ASA was significantly worse in women compared with men with HOCM. Sex may need to be considered as an important factor in the clinical management of patients with symptomatic HOCM.

Efficacy and safety of standard and low dose ticagrelor versus clopidogrel in east AsianPatients with chronic total occlusion undergoing percutaneous coronary intervention: a single center retrospective study.

BACKGROUND: Patients with coronary chronic total occlusion (CTO) require effective antiplatelet therapy after percutaneous coronary intervention (PCI). Ticagrelor has more pronounced platelet inhibition than clopidogrel. However, the most appropriate dose of ticagrelor in East Asian populations remains unclear. METHOD: We compared ticagrelor (180 mg loading dose, 90 mg twice daily thereafter and 120 mg loading dose, 60 mg twice daily thereafter) and clopidogrel (300 mg loading dose, 75 mg daily thereafter) for prevention of cardiovascular events in 525patients with CTO undergoing PCI. RESULTS: The rate of in-hospital major adverse cardiac and cerebral events (MACCE) was not different between the groups. At 1-year follow-up, target vessel revascularization (TVR) in both ticagrelor groups were significantly lower than that in the clopidogrel group (p = 0.047); TVR was significantly decreased in 60 mg ticagrelor compared to standard dose clopidogrel (p = 0.046). At 1-year follow-up, overall MACCE in both ticagrelor groups were significantly lower than that in the clopidogrel group (p = 0.023). Kaplan-Meier analysis showed MACCE-free survival was significantly higher in both ticagrelor groups than in the clopidogrel group (p = 0.024). During hospitalization, minor bleeding was significant increased in the 90 mg ticagrelor group (p = 0.021). At 1-year follow-up, risk of major and minor bleeding were significantly increased in the 90 mg ticagrelor group. CONCLUSION: In East Asian patients with CTO undergoing PCI, 60 mg ticagrelor was as effective as 90 mg, at the same time significantly reduced risk of bleeding.

Incidence, Predictors, and Prognosis of Coronary Slow-Flow and No-Reflow Phenomenon in Patients with Chronic Total Occlusion Who Underwent Percutaneous Coronary Intervention.

BACKGROUND: The incidence and prognosis of coronary slow-flow (CSF) and no-reflow phenomenon (NRP) in patients with coronary chronic total occlusion (CTO) who underwent percutaneous coronary intervention (PCI) remain unclear. METHODS: This single-center prospective study aimed to investigate the incidence of CSF/NRP during CTO interventional therapy, determine predictors of CSF/NRP, and evaluate its effect on patient outcomes. RESULTS: In this study, 552 patients with CTO who underwent PCI were included. CSF/NRP occurred in 16.1% of them. They had higher incidences of diabetes mellitus (53.9% vs 36.3%, p=0.002) and hypertension (50.6% vs 37.1%, p=0.018) and a lower incidence of retrograde filling grade >2 (34.8% vs 47.1%, p=0.036). Patients with CSF/NRP had a higher neutrophil ratio (55.6±19.4 vs 52.4±18.3, p=0.038) and levels of low-density lipoprotein (LDL; 3.0±0.8 vs 2.8±0.6, p=0.029), fasting glucose (FG; 8.3±1.3 vs 6.8±1.1, p=0.005), uric acid (332.6±82.9 vs 308.2±62.8, p=0.045), and high-sensitivity C-reactive protein (Hs-CRP; 9.8±4.8 vs 7.3±3.9, p=0.036). A multivariate logistic regression analysis revealed that diabetes mellitus (odds ratio [OR], 1.962; 95% confidence interval [CI]: 1.198-2.721; p=0.042), mean platelet volume (MPV; OR,1.284; 95% CI, 1.108-1.895; p=0.046), LDL cholesterol (LDL-C; OR, 1.383; 95% CI, 1.105-2.491; p=0.036), FG (OR, 2.095; 95% CI, 1.495-2.899; p=0.018), Hs-CRP(OR, 2.218; 95% CI, 1.556-3.519; p=0.029), and retrograde filling of grade >2 (OR, 0.822; 95% CI, 0.622-0.907; p=0.037) were independent predictors of CSF/NRP in CTO patients who underwent PCI. Kaplan-Meier analysis revealed that the patients in the CSF/NRP group had a significantly lower cumulative major cardiac and cerebrovascular events (MACCE)-free survival than those in the non-CSF/NRP group (p<0.0001). CONCLUSION: Of the patients with CTO who underwent PCI, 16.1% developed CSF/NRP and had a significantly lower cumulative MACCE-free survival rate. Diabetes mellitus; higher levels of MPV, LDL-C, FG, and Hs-CRP; and a lower incidence of retrograde filling grade >2 were independent predictors of CSF/NRP in CTO patients who underwent PCI. Thus, they can be used for risk stratification.

Intrathecal Morphine Delivery at Cisterna Magna to Control Refractory Cancer-Related Pain: A Prospective Cohort Study.

Background: For patients suffering from primary or metastatic cancer above the middle thoracic vertebrae, refractory pain management still remains a great challenge. Theoretically, inserting a catheter tip into the cisterna magna may be a promising solution. However, at present, there have been no reliable data regarding this novel technique. We therefore investigated the efficacy and safety of an advanced approach for pain relief in a specific population. Methods: Thirty participants from two hospitals received the intrathecal deliveries of opioid to either one of two sites: cisterna magna (n = 15) or lower thoracic region (n = 15). Pain relief (visual analogue scale, VAS), quality of life (short form (36) health survey, SF-36) as well as depression (self-rating depression scale, SDS) were assessed in the follow-up visits and compared between the two groups. Results: Patients receiving intrathecal morphine delivery to cisterna magna achieved greater pain improvement indicated as significant decrease of VAS scores at day 1 and 7, and achieved better improvement in physical function (day 7 and 30), role physical (day 7 and 30), body pain (day 7, 30 and 90), general health (day 7, 30 and 90), vitality (day 7, 30 and 90), social function (day 90), role emotional (day 7 and 90), mental health (day 7, 30 and 90) and SDS (day 1 and 7). Conclusions: Intrathecal morphine delivery to cisterna magna might be an effective and safe technique for patients suffering from cancer at the middle thoracic vertebrae or above to control refractory pain. Trial registration: No. ChiCTR-ONN-17010681.

Efficacy and safety of bivalirudin during percutaneous coronary intervention in high-bleeding-risk elderly patients with chronic total occlusion: A prospective randomized controlled trial.

OBJECTIVES: To assess the efficacy and safety of bivalirudin during percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) in high-bleeding-risk elderly patients. BACKGROUND: Bivalirudin reduces PCI-related bleeding; however, its efficacy and safety in patients with CTO, especially elderly patients with a high bleeding risk, remain unclear. METHODS: This single-center prospective randomized controlled trial assigned 123 high-bleeding-risk elderly patients with CTO to either the unfractionated heparin (UFH) group (n = 55) or the bivalirudin group (n = 68). The primary efficacy endpoint was the incidence of major adverse cardiac events (MACEs) during hospitalization and at the 6-month follow-up. The safety endpoint was bleeding or procedure (access)-related complications after PCI. RESULTS: MACE incidence was 17.6% and 20.0% in the bivalirudin and UFH groups, respectively (P = 0.82). Bleeding Academic Research Consortium (BARC) type 1-2 bleeding events during hospitalization were comparable between the groups (UFH: 10.9% vs. bivalirudin: 8.8%, P = 0.77). No BARC type 3-5 bleeding events or severe procedure (access)-related complications (subcutaneous hematoma >5 cm) occurred in either group. At the 6-month follow-up, MACE incidence was comparable between the groups (UFH: 3.6% vs. bivalirudin: 1.5%, P = 0.59). The Kaplan-Meier analysis revealed that MACE-free survival rates were comparable between the groups (P = 0.43). One case of BARC type 3-5 bleeding (fatal intracranial hemorrhage) was observed in the UFH group at the 6-month follow-up. CONCLUSIONS: Bivalirudin and UFH showed comparable efficacy and safety in elderly patients with a high bleeding risk, undergoing PCI for CTO lesions.

[Effect of L-arabinose on the postprandial blood glucose and body weight].

OBJECTIVE: To study the effect of L-arabinose on the blood glucose level of adult, and to find out the optimal amount of daily L-arabinose intake for maintaining their health. METHODS: 50 adult were randomly selected and assigned to 5 group with different dose of L-arabinose or placebo, respectively. The preprandial blood glucose level and 1 h and 2h postprandial blood glucose were detected per 3 days. To investigate the variation of weight, 20 fat person was performed with daily L-arabinose or placebo intake for given daily for six months. Results After 30 days feeding, the decrease of postprandial blood glucose level was observed in group with 3% L-arabinose sample, and the groups with 5% - 10% have a significantly decreasing in the postprandial blood glucose level compared with control group result in (5.60 +/- 0.08) and (5.24 +/- 0.12), respectively (P < 0.05). The average body weight have a significantly reduce and after six months averagely reduced 5.5 kg, and the control group have no obviously variation. CONCLUSION: The daily consumption of L-arabinose would inhibit the postprandial blood glucose level and slimming down body which have a benefit for heath.

Improved co-production of S-adenosylmethionine and glutathione using citrate as an auxiliary energy substrate.

The effects of sodium citrate on the fermentative co-production of S-adenosylmethionine (SAM) and glutathione (GSH) using Candida utilis CCTCC M 209298 were investigated. Sodium citrate was beneficial for the biosynthesis of SAM and GSH and in turn improved intracellular SAM and GSH contents. Adding 2 g/L of sodium citrate at 15 h was the most efficient approach for achieving elevated co-production of SAM and GSH. Using this sodium citrate addition mode, co-production of SAM and GSH reached 663.9 mg/L, which was increased by 27.5% compared to the control. Based on analysis of the kinetic parameters, evaluation of the energy metabolism and assay of key enzymes, sodium citrate was verified to act as an auxiliary energy substrate for the overproduction of SAM and GSH.

Efficient preparation of selenium/glutathione-enriched Candida utilis and its biological effects on rats.

The main purpose of this study was to prepare selenium/glutathione-enriched Candida utilis and investigate its effect on growth performance, antioxidant capacity, and immune response in rats. The preparation of the selenium/glutathione-enriched yeast was conducted using fed-batch culture for high cell density. The optimal culture conditions for increased intracellular organic selenium and glutathione contents were as follows: the concentrated medium was fed beginning at 12 h using a polynomial feeding strategy until a total glucose concentration of 150 g/l was reached, and sodium selenite was continuously added together with glucose to a total concentration of 60 mg/l. As a result, 81 % of sodium selenite was assimilated and transformed into organic selenium by C. utilis under optimal conditions, which in turn resulted in greater glutathione accumulation and lower malondialdehyde cellular content in the yeast. To investigate and compare the effects of the prepared selenized C. utilis and other dietary supplements, 40 female rats were divided into five groups of eight rats each, following a randomized block design. Experimental feeding was conducted for a period of 6 weeks. Selenium supplementation with inorganic selenium (sodium selenite) and organic selenium (selenized C. utilis) showed better results than the control and other groups supplemented with yeast with or without glutathione. The body mass of rats, selenium deposition, and oxidative enzymes activities in both serum and liver samples, and immunity responses were all significantly improved by selenium supplementation, and between the two sources, organic selenium was more effective than inorganic selenium.

Anatomy of the replication origin of plasmid ColE2-P9.

The plasmid ColE2-P9 origin is a 32-bp region which is specifically recognized by the plasmid-specified Rep protein to initiate DNA replication. We analyzed the structural and functional organization of the ColE2 origin by using various derivatives carrying deletions and single-base-pair substitutions. The origin may be divided into three subregions: subregion I, which is important for stable binding of the Rep protein; subregion II, which is important for binding of the Rep protein and for initiation of DNA replication; and subregion III, which is important for DNA replication but apparently not for binding of the Rep protein. The Rep protein might recognize three specific DNA elements in subregions I and II. The relative transformation frequency of the autonomously replicating plasmids carrying deletions in subregion I is lower, and nevertheless the copy numbers of these plasmids in host bacteria are higher than those of the wild-type plasmid. Efficient and stable binding of the Rep protein to the origin might be important for the replication efficiency to be at the normal (low) level. Subregion II might be essential for interaction with the catalytic domain of the Rep protein for primer RNA synthesis. The 8-bp sequence across the border of subregions II and III, including the primer sequence, is conserved in the (putative) origins of many plasmids, the putative Rep proteins of which are related to the ColE2-P9 Rep protein. Subregion III might be required for a step that is necessary after Rep protein binding has taken place.