ST Activity Research Articles

Pediatric Intensive Care Unit Early Mobility Program: Impact on Patient Functional Status.

Patients admitted to the pediatric Intensive Care Unit (PICU) are frequently sedated, restrained, and placed on bed rest. These practices have known negative impacts including prolonged hospital stay and diminished functional status after discharge. The authors' objective was to investigate the impact of a PICU early mobility protocol on the frequency of orders for physical, occupational, and speech therapy (PT, OT, ST) and improvement in patient functional status. Patients admitted in 2019 prior to the development of the PICU early mobility protocol were compared to those admitted in 2020 who underwent the protocol. Differences in clinical characteristics; PICU length of stay; rates of PT, OT, and ST orders; rates of bedside mobility activities; and functional status scores (FSSs) were assessed in bivariate and multivariate analyses. The protocol included early PT, OT, and ST order placement and frequent in-room mobility activities. Of the 384 patients included in the study, 216 (56%) were preprotocol patients, and 168 (44%) underwent the protocol. Patients in 2020 were more likely to receive a physical therapy order compared to their 2019 counterparts (79% vs 47%, p < 0.001). Patients in 2020 had a higher daily incidence of mobility activities compared to those in 2019 (4.88 activities vs 4.1 activities, p < 0.001). Changes in functional status scores were similar between the 2 groups. PICU early mobility was associated with increased physical, occupational, and speech therapy orders and daily mobility activities but was not associated with a reduction in functional morbidity at discharge or 3 months post-discharge.

Implementation of Self-Talk Cues for University Instructional Physical Activity Programs as a Best Practice Approach

The purpose of this article is to help instructors or other types of faculty to develop their own ST activity cues by working with individual students, or with the entire class in order to increase the students’ role in affecting the learning process.

Abstract IA019: Clinical trials of GUCY2C (GCC) agonists for colorectal cancer prevention

Abstract Guanylyl cyclase C (GUCY2C), expressed on intestinal epithelial cells, is the receptor for heat-stable enterotoxins (STs) produced by diarrheagenic bacteria. Fluid secretion reflects ST activation of GUCY2C, which produces cyclic (c)GMP activating ion channels. Beyond toxins, GUCY2C binds uroguanylin in small intestine and guanylin in colorectum, which also stimulate secretion. This mechanism is the basis for the oral agonists linaclotide (ST analog) and plecanatide (uroguanylin analog) to treat constipation. Guanylin is the most commonly lost gene product, while GUCY2C expression is retained, in colorectal tumors. Eliminating GUCY2C promotes tumor formation, while oral GUCY2C agonists or transgenic guanylin reduce intestinal tumors, in mice. These data support a hypothesis in which loss of guanylin silencing GUCY2C is a key step in intestinal transformation which can be prevented by oral GUCY2C agonists. However, GUCY2C agonists are formulated for duodenal activity, without bioavailability in the colorectum. Here, we explored whether this pharmacokinetic (PK) barrier could be abrogated with high doses (HD) of linaclotide. Indeed, HD linaclotide induced a cGMP response in mucosal biopsies obtained by colonoscopy following oral polyethylene glycol (PEG) preparation. This cGMP response was validated by VASP phosphorylation and suppression of crypt proliferation. Similarly, HD linaclotide induced cGMP in colon biopsies obtained by sigmoidoscopy following oral PEG. However, HD linaclotide failed to induce cGMP in colon biopsies obtained by sigmoidoscopy i n the absence of oral PEG . Thus, oral PEG abrogated the PK barrier, delivering linaclotide to the colorectum. Unfortunately, dolcanatide, a proteolysis-resistant analog of plecanatide, also failed to overcome the colorectal PK barrier, although it produced duodenal secretion and diarrhea. Thus, guanylin loss silencing GUCY2C appears to be a key step in intestinal transformation. Preclinical models suggest that oral GUCY2C agonists stimulate GUCY2C signaling, opposing tumorigenesis. However, translation of these observations appears to be constrained by a PK barrier, reflecting agonists formulated for duodenal activity, without colorectal bioavailability. Exploiting GUCY2C for chemoprevention awaits agonists formulated for the colorectum. We are exploring the ability of GUCY2C agonists to activate cGMP in duodenum (within the PK barrier), as a prelude to trials in patients with FAP at risk for duodenal tumors. Citation Format: Scott A. Waldman. Clinical trials of GUCY2C (GCC) agonists for colorectal cancer prevention [abstract]. In: Proceedings of the Second Biennial NCI Meeting: Translational Advances in Cancer Prevention Agent Development (TACPAD); 2022 Sep 7-9. Philadelphia (PA): AACR; Can Prev Res 2022;15(12 Suppl_2): Abstract nr IA019.

Innovation and Development of Guangdong-Hong Kong-Macao Capital Market Based on Fintech

The development of the capital market will face challenges. Promoting the optimization of the capital market in the guangdong-hong kong-macao (CHM) Greater Bay Area (GBA) with the development of emerging FT is not only of practical significance to the development of the GBA, but also of great significance to promoting the country's overall economic competitiveness and realizing modernization. In the context of the rapid development of FT, the practical and theoretical significance of capital market optimization in the CHM GBA is analyzed. The new generation of FT means such as big data, cloud computing, artificial intelligence, blockchain, and Internet payment are the mainstays of CHM University. Possibilities analysis of Bay Area capital market optimization offers. Based on this background, this paper conducts research on the innovative development of capital markets in CHM based on financial technology (FT).This paper mainly studies the status quo of financial support for technological innovation in the CHM GBA, summarizes the main practices of financial support for technological innovation in the three major bay areas in the world, and draws the following points: First, it is necessary to establish a ST innovation system according to the national conditions of a country. financial support system. Second, policy finance plays a guiding role in the initial stage of ST innovation activities. Third, commercial banks play an important role as a booster in technological innovation activities. Fourth, a sound credit guarantee system provides a strong guarantee for technological innovation. Fifth, developed venture capital and perfect multi-level capital market can effectively speed up the development of ST innovation.

Convolutional Neural Networks Quantization with Double-Stage Squeeze-and-Threshold.

It has been proven that, compared to using 32-bit floating-point numbers in the training phase, Deep Convolutional Neural Networks (DCNNs) can operate with low-precision during inference, thereby saving memory footprint and power consumption. However, neural network quantization is always accompanied by accuracy degradation. Here, we propose a quantization method called double-stage Squeeze-and-Threshold (double-stage ST) to close the accuracy gap with full-precision models. While accurate colors in pictures can be pleasing to the viewer, they are not necessary for distinguishing objects. The era of black and white television proves this idea. As long as the limited colors are filled reasonably for different objects, the objects can be well identified and distinguished. Our method utilizes the attention mechanism to adjust the activations and learn the thresholds to distinguish objects (features). We then divide the numerically rich activations into intervals (a limited variety of numerical values) by the learned thresholds. The proposed method supports both binarization and multi-bit quantization. Our method achieves state-of-the-art results. In binarization, ReActNet [Z. Liu, Z. Shen, S. Li, K. Helwegen, D. Huang and K. Cheng, arXiv:abs/2106.11309] trained with our method outperforms the previous state-of-the-art result by 0.2 percentage points. Whereas in multi-bit quantization, the top-1 accuracy of the 3-bit ResNet-18 [K. He, X. Zhang, S. Ren and J. Sun, Deep residual learning for image recognition, 2016 IEEE Conf. Computer Vision and Pattern Recognition, CVPR 2016, 27-30 June 2016, Las Vegas, NV, USA (IEEE Computer Society, 2016), pp. 770-778] model exceeds the top-1 accuracy of its full-precision baseline model by 0.4 percentage points. The double-stage ST activation quantization method is easy to apply by inserting it before the convolution. Besides, the double-stage ST is detachable after training and introducing no computational cost in inference.

Effects of camphor and related compounds on slowly adapting mechanoreceptors in the rat sinus hair follicle.

IntroductionCamphor is a popular compound for therapeutic and cosmetic use with a distinctive odour, and somatosensory warming and cooling properties. The mechanisms for its action remain unclear.ObjectiveThe current study examined the effects of two enantiomers of camphor and related monoterpenoid compounds on mechanoreceptors.MethodsExtracellular recordings were made in an in vitro bath preparation. Camphor, borneol, eugenol, carveol, and thymol were tested on the neural activity of St I and St II slowly adapting mechanoreceptors in the rat vibrissal hair follicle preparation.ResultsAll compounds tested (0.5 – 2 mM bath concentrations) resulted in dose-dependent depression of spontaneous and mechanically evoked firing (dynamic and static phases). The mean latency of responses also increased. Both St I and St II were similarly affected, although (-)-camphor had a greater depressant effect on St II than on St I units. Differences were found across the different compounds for their effect on the dynamic and static phases. Thymol was found to have the greatest depressant effect on these phases. The broad spectrum TRP blocker ruthenium red did not reverse the depressant effects of camphor. The depressant effects of the compounds appeared similar to those obtained using the local anaesthetic lignocaine. The depressant effects of camphor and of lignocaine were partially reversed by the K+ channel blocker tetraethylammonium.ConclusionsThe results question whether the depressant effects of camphor and related compounds act through TRP channels. Perhaps the use of more selective blockers may reveal the molecular mechanisms through which these compounds act.

Acute myeloid leukemia causing acute thrombosis of the\xa0coronary arteries: a\xa0case report

BackgroundThis case report demonstrates acute myeloid leukemia causing acute thrombosis of coronary arteries with anterolateral ST elevation myocardial infarction and ventricular tachycardia in an otherwise healthy woman. Few case reports have been documented on patients with concomitant conditions of acute myeloid leukemia and acute myocardial infarction, and it is important to note that prognosis for patients with both is worse than that of either condition. While both conditions together are rare, other non-atherosclerotic causes of acute coronary syndromes are likewise important considerations in the context of myocardial ischemia.Case presentationA 59-year-old Caucasian woman with no notable past medical history presented to her primary care provider with 2 weeks of severe fatigue, anorexia, and malaise, associated with chills, night sweats, and myalgias. Peripheral blood smear identified 92% blasts consistent with acute myeloid leukemia and computed tomography identified a right segmental pulmonary embolism and thrombotic infarcts in the spleen, bilateral kidneys, right lung, and liver. Laboratory testing also demonstrated disseminated intravascular coagulopathy. She was admitted to the intensive care unit for treatment and subsequently developed ventricular tachycardia, anterolateral ST segment elevation, acute dysarthria, and nonreactive pupils. Pulseless electrical activity developed with unsuccessful resuscitative measures. The patient died secondary to presumed cerebrovascular and coronary thromboses causing stroke and anterolateral infarct complicated by ventricular tachycardia and pulseless electrical activity.ConclusionThis case is notable as a case of acute myeloid leukemia causing acute thrombosis of coronary arteries with anterolateral ST elevation myocardial infarction, ventricular tachycardia, and pulseless electrical activity. Prognosis of concomitant acute myeloid leukemia and acute myocardial infarction is poor. Management is challenging due to thrombocytopenia, platelet dysfunction, and systemic coagulopathy, and administration of thrombolytic agents can be fatal. This is an extreme presentation of a case of acute myocardial infarction with disseminated intravascular coagulopathy causing acute coronary thrombosis and sudden death with dramatic electrocardiogram and telemetry findings recorded with rapid progression from normal sinus rhythm to acute myocardial infarction to terminal rhythm.

P–356 Oral administration of sodium tungstate to a swine model improves embryo implantation rate

Abstract Study question Does sodium tungstate treatment improve embryo implantation and therefore, fertility in large mammals? Summary answer Oral administration of sodium tungstate increases embryo implantation and reproductive efficiency in large mammals. What is known already Sodium tungstate (ST) has shown its capacity to modulate critical molecules in the embryo implantation process. ST showed a positive effect on PCOS-like model to restore ovulation and fertility. Moreover, ST proved to act directly on the endometrium to increase embryo adhesion in in vitro assays. There is an inherent difficulty in studying implantation using in vivo models due to the close communication between ovary, embryo and endometrium. For the current study, the Large-White swine breed has been selected because of its high efficiency in ovulatory and fertilisation processes, minimising low embryo quality interferences in the implantation process. Study design, size, duration A randomised, blinded, prospective, placebo-controlled study was performed to evaluate ST effect on fertility, ovulation, and embryo implantation rates in swine, which is characterised by a high fertilisation rate but a limiting implantation rate. Forty-four primiparous Large-White sows (8 months old) were orally-treated with ST or placebo for 44–46 days, from 10 days prior to starting a progestin-based treatment for ovulation induction to gestational days 11th–13th (i.e., the window of implantation in swine). Participants/materials, setting, methods: Animals were randomised in treatment groups based on body weight ranges and housed individually in temperature-controlled conditions. 2.5g ST (diluted in 5ml of distilled water) or vehicle were once-daily orally administered with a syringe. Sows responding to ovulation-induction protocols were inseminated with high-quality sperm from untreated pigs and euthanised at gestational days 28–30 (1st pregnancy trimester) to recover genital tracts. Pregnancy, number of ovulations, number of viable/non-viable implanted embryos and fetal measurements were immediately recorded. Main results and the role of chance All 44 sows involved in the study responded to ovulation induction and were inseminated, but 4 females were excluded from the study because of uterine anatomical abnormalities (unicornuate uterus) or abnormalities during pregnancy. Hence, 19 ST-treated and 21 placebo sows were eligible.There were no differences in pregnancy rate (pregnancy was observed in 17 ST-treated sows 19 placebo-treated sows; 89.47% and 90.48%, respectively) or number of ovulations (21.5±4.1 vs 21.8±2.9 in placebo and treated animals, respectively; p = 0.300). However, implantation rate was significantly improved in ST-treated animals, since the number of implanted embryo was found to be increased by 15% per sow in the ST-treated group; which means two additional good-quality embryos per sow (16.5±3.2 in the ST group vs 14.4±3.9 in the placebo group, p &amp;lt; 0.05). The percentage of viable implantations, calculated as the number of viable embryos divided by the total number of viable and non-viable implanted embryos was also increased by the ST treatment (91.6±7.9 vs 96.2±4.7 in treated vs placebo groups, p &amp;lt; 0,05). Finally, there were no effects of the treatment on the foetal phenotype, body mass and size. Limitations, reasons for caution The current study is the first attempt to evaluate ST effect on reproductive outcomes, in healthy large mammals. Having in mind that the selected model is high reproductive efficient, further studies assessing ST effects in infertile and sub-fertile mammals should be performed to elucidate ST activity in suboptimal fertility conditions. Wider implications of the findings: Sodium tungstate treatment proves, for the first time, the improvement of fertility in healthy large mammals. Sodium tungstate treatment improves endometrial implantation and therefore, fertility efficiency. Thus, after subsequent further research, sodium tungstate may become a potential treatment for improving embryo implantation, an unmet medical need. Trial registration number Not applicable

Effect of hindlimb unloading on recruitment of gastrocnemius medialis muscle during treadmill locomotion in rats.

After hindlimb unloading (HU), the adaptive changing of the rat step cycle duration, kinematics of the ankle and knee joints, and duration of one-joint ankle extensor m. soleus (SOL) activity are detected. However, how the activity of their synergist gastrocnemius medialis muscle (GM) changes in locomotion after HU remains unknown. GM is a two-joint muscle that produces both extension and flexion torques at the ankle and knee, respectively, regardless of the step cycle phase. The aim of our study was to assess changes in the flexor and extensor activity of GM and their influence on hindlimb kinematics after HU. The hindlimb kinematics, activity of GM, and SOL were evaluated, and semitendinosus muscle (ST) activity was registered in six Wistar rats in treadmill locomotion before and after HU. The mean EMG of the GM activity, which was co-active with ST burst activity, significantly increased after HU. The mean EMG of the GM activity, which was co-active with SOL activity, was unchanged after HU, but both SOL and GM bursts had a tendency to increase in duration. Hyperextension of the knee joint and the tendency to overextension of the ankle joint in the late of the stance phase were revealed after HU. The results show that the absence of weight bearing leads to an increase only in the flexor activity of GM and does not affect the extensor GM activity. Possible mechanisms of changes in GM activity and joint kinematics after HU are discussed.

Medio-Lateral Hamstring Muscle Activity in Unilateral vs.Bilateral Strength Exercises in Female Team Handball Players - A Cross-Sectional Study.

BackgroundReduced activation of the hamstring muscles and specifically the medial semitendinosus muscle (ST) has been shown to be a risk factor for non-contact anterior cruciate ligament (ACL) injury. Specific hamstring strength exercises may show high ST activity, however the effect of unilateral vs. bilateral exercise execution on ST activation remains unknown.PurposeTo investigate selected lower limb strengthening exercises performed either unilaterally or bilaterally to identify 1) which exercise elicited the highest hamstring activation, 2) which exercise elicited the highest ST activation, and 3) to examine if unilateral exercise execution altered the medio-lateral hamstring activation pattern. Furthermore, the kinematic characteristics of each specific exercise and execution modality were determined to reveal possible causes for differences in medio-lateral hamstring activation between the different exercise conditions.Study designCross-sectional study.MethodsSingle-session repeated measures were obtained in a randomized manner. Twenty-three female elite team handball players were recruited. Hamstring electromyographic (EMG) activity and 3D kinematics were obtained during selected lower limb exercises (hip thrust, kettlebell swing, Romanian deadlift). Hamstring EMG activity, normalized to maximal voluntary contraction (MVC) (nEMG), and inter-muscular activation difference between the ST and lateral hamstring biceps femoris (BF) were compared across exercises using two-way repeated measures ANOVA.ResultsBilateral hip thrust demonstrated highest overall hamstring activity (68.9±16.6 %). Kettlebell swing (Δ13%-point, p<0.01) and Romanian deadlift (Δ20-24%-point, p<0.01) demonstrated greater ST-BF activation differences (Δ=ST-BF) in favor of ST compared to hip thrust (Δ2-7%). Positive correlations were observed between knee joint angle and ST activity in kettlebell swing and deadlift.ConclusionKettlebell swing, deadlift and hip thrust all produced high activation of the hamstring muscles. Kettlebell swing and both deadlift exercises were superior in activating ST over BF, favoring these exercises in the prevention of non-contact ACL injury in female athletes, which should be evaluated in future intervention studies.Level of evidence3

Orthologous CRISPR/Cas9 systems for specific and efficient degradation of covalently closed circular DNA of hepatitis B virus.

Covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV) is the major cause of viral persistence and chronic hepatitis B. CRISPR/Cas9 nucleases can specifically target HBV cccDNA for decay, but off-target effects of nucleases in the human genome limit their clinical utility. CRISPR/Cas9 systems from four different species were co-expressed in cell lines with guide RNAs targeting conserved regions of the HBV genome. CRISPR/Cas9 systems from Streptococcus pyogenes (Sp) and Streptococcus thermophilus (St) targeting conserved regions of the HBV genome blocked HBV replication and, most importantly, resulted in degradation of over 90% of HBV cccDNA by 6days post-transfection. Degradation of HBV cccDNA was impaired by inhibition of non-homologous end-joining pathway and resulted in an erroneous repair of HBV cccDNA. HBV cccDNA methylation also affected antiviral activity of CRISPR/Cas9. Single-nucleotide HBV genetic variants did not impact anti-HBV activity of St CRISPR/Cas9, suggesting its utility in targeting many HBV variants. However, two or more mismatches impaired or blocked CRISPR/Cas9 activity, indicating that host DNA will not likely be targeted. Deep sequencing revealed that Sp CRISPR/Cas9 induced off-target mutagenesis, whereas St CRISPR/Cas9 had no effect on the host genome. St CRISPR/Cas9 system represents the safest system with high anti-HBV activity.

Comparing coagulation activity of Selaginella tamariscina before and after stir-frying process and determining the possible active constituents based on compositional variation

Context: Selaginella tamariscina (P. Beauv.) Spring (Selaginellaceae) (ST) has been widely used in China as a medicine for improving blood circulation. However, its processed product, S. tamariscina carbonisatus (STC), possesses opposite haemostatic activity.Objective: To comprehensively evaluate the activity of ST and STC on physiological coagulation system of rats, and seek potential active substances accounting for the activity transformation of ST during processing.Materials and methods: The 75% methanol extracts of the whole grass (fine powder) of ST and STC were prepared, respectively. Male Sprague–Dawley rats were randomly divided into five groups: control group, model group, model + ST group, model + STC group and positive control group (model + Yunnanbaiyao). The duration of intragastric administration was 72 h at 12 h intervals. Haemorheology parameters were measured using an LB-2 A cone-plate viscometer and the existed classic methods, respectively. SC40 semi-automatic coagulation analyzer was employed to determine coagulation indices. Meanwhile, HPLC and LC-MS were applied for chemical analyses of ST and STC extracts.Results: STC shortened tail-bleeding time, increased whole blood viscosity (WBV) and plasma viscosity (PV), decreased erythrocyte sedimentation rate blood (ESR), reduced activated partial thromboplastin time (APTT) and increased the fibrinogen (FIB) content in the plasma of bleeding model rats. Although ST could shorten APTT and TT, the FIB content was significantly decreased by ST. Dihydrocaffeic acid with increased content in STC vs. ST showed haemostatic activity for promoting the platelet aggregation induced by collagen and trap-6, and reducing APTT and PT significantly with a concentration of 171.7 μM in vitro. Amentoflavone with reduced content in STC vs. ST inhibited ADP and AA-induced platelet aggregation significantly with a concentration of 40.7 μM.Discussion and conclusions: As the processed product of ST, STC showed strong haemostatic activity on bleeding rat through regulating the parameters involved in haemorheology and plasma coagulation system. Two active compounds, dihydrocaffeic acid and amentoflavone, might be partially responsible for the haemostatic and anticoagulant activity of STC and ST, respectively.

Relationship between time of initial diagnosis of acute myocardial infarction to primary angioplasty on patient’s outcome

OBJECTIVES: To explore the relationship between time of initial diagnosis of acute myocardial infarction to primary angioplasty on patient’s outcome. MATERIAL AND METHODS: A systematic review of published articles in international databases (CENTRAL, SCOPUS and MEDLINE). A time limited criterion was applied related to the articles publication (articles published between 2012 and 2016). Seventeen articles were found that met the criteria for participation in the review. RESULTS: According to the results, the majority of studies showed that time to treatment (primary angioplasty) was less than 90 minutes from the initial assessment, resulting in better outcomes of patients. The time from patient presentation to hospital in ST segment elevetion myocardial infarction (STEMI) diagnosis and laboratory activation for catheterization is a powerful guide to the total time from admittance to primary percutaneous coronary intervention (PPCI). In some of the stydies were described the effect of time from assessment on initiation of angioplasty in patients short-term or long-term outcomes and in others were investigated the reasons of delay until the onset of primary angioplasty. Endly in some were found time reduction practices from assessment to the onset of angioplasty and improving the clinical outcome. CONCLUSION: Early treatment is important for the best clinical outcomes of patients with acute myocardial infarction (AMI) and seems to be feasible.

The structural features of the sulfated heteropolysaccharide (ST-1) from Sargassum thunbergii and its neuroprotective activities

Polysaccharide (ST) was prepared from Sargassum thunbergii using hot water. Two fractions (ST-1 and ST-2) were prepared using anion exchange chromatography. One desulfated polysaccharide (ST-1-DS) was also prepared. Electrospray ionization mass spectrometry (ESI–MS) performed on ST-1-DS showed that the desulfated polysaccharides contained methyl glycosides of mono-sulfated and di-sulfated galacto-fucooligosaccharides. This result suggested that ST-1 might contain sulfated galactofucan, which consists of a backbone of alternating (Gal)n and (Fuc)n and sulfated randomly on Gal and mainly on C-2 in Fuc. In addition, ST-1 was degraded in 1M sulfuric acid. The solution was centrifuged, and the supernatant was concentrated and precipitated in ethanol to obtain the precipitate (ST-1-P). ST-1-P was then separated using gel chromatography and anion exchange chromatography to obtain the oligomers. ESI–MS spectra of oligomers indicated that ST-1 mostly contained sulfated glucuronomannan and fucoglucuronan. ESI–MS with collision-induced dissociation tandem mass spectrometry (ESI-CID-MS/MS) suggested that glucuronomannan contained alternating 2-linked Man and 4-linked GlcA, while fucoglucuronan contained 4-linked glucuronan with branched Fuc at C-3. Finally, the neuroprotective activities of ST, ST-1, ST-2 and MIX (a mixture of ST-1 and ST-2) were determined. ST showed the most neuroprotective activity, which indicated that ST might be a good candidate for curing neurodegenerative diseases.

Variation of active constituents and antioxidant activity in Scabiosa tschiliensis Grunning from different stages.

It has been claimed that inflorescences of Scabiosa tschiliensis Grunning (ST) may prevent liver diseases because of its higher chlorogenic acid. There was scant information on the phytochemical profiles and antioxidant activities of the whole plant from different growing stages. The changes of active-compounds and antioxidant activities of ST from three growing stages were studied. Total phenolic and flavonoid contents were analyzed and ranged from 0.00 to 140.03mg GAE/g and 9.10 to 460.01mg RE/g, respectively. The pre-flowering stage ethyl acetate (PFSEA) fraction of ST appeared to contain the highest content of chlorogenic acid, and demonstrated the highest DPPH radical-scavenging activity with the IC50 value of 8.47±0.23µg/mL which was nearly equal to the IC50 value of vitamin C (7.60±0.61µg/mL). Principal component analysis suggested that the PFSEA fraction of ST might be a desirable antioxidant natural resource due to the highest potential antioxidant properties.

Two N-terminally truncated variants of human β-galactoside α2,6 sialyltransferase I with distinct properties for invitro protein glycosylation.

Sialic acid groups of protein N-glycans are important determinants of biological activity. Exposed at the end of the glycan chain, they are potential targets for glycan remodeling. Sialyltransferases (STs; EC 2.4.99) are the enzymes that catalyze the sialic acid transfer from a CMP-activated donor on to a carbohydrate acceptor in vivo. Recombinant expression of the full-length human β-galactoside α2,6 sialyltransferase I (ST6Gal-I) was hampered and therefore variants with truncated N-termini were investigated. We report on the distinct properties of two N-terminally truncated versions of ST6Gal-I, namely Δ89ST6Gal-I and Δ108ST6Gal-I, which were successfully expressed in human embryonic kidney cells. The different properties of these enzymes result most probably from the loss of interactions from helix α1 in the Δ108ST6Gal-I variant, which plays a role in acceptor substrate binding. The Km for N-acetyl-d-lactosamine was 10-fold increased for Δ108ST6Gal-I (84 mM) as compared to Δ89ST6Gal-I (8.3 mM). The two enzyme variants constitute a suitable tool box for the terminal modification of N-glycans. While the enzyme Δ89ST6Gal-I exhibited both ST (di-sialylation) and sialidase activity on a monoclonal antibody, the enzyme Δ108ST6Gal-I showed only ST activity with specificity for mono-sialylation.

The Presence of Sterols Favors Sticholysin I-Membrane Association and Pore Formation Regardless of Their Ability to Form Laterally Segregated Domains.

Sticholysin I (St I) is a pore-forming toxin (PFT) produced by the Caribbean Sea anemone Stichodactyla helianthus belonging to the actinoporin protein family, a unique class of eukaryotic PFT. As for actinoporins, it has been proposed that the presence of cholesterol (Chol) and the coexistence of lipid phases increase binding to the target membrane and pore-forming ability. However, little is known about the role of membrane structure and dynamics (phase state, fluidity, and the presence of lipid domains) on the activity of actinoporins or which regions of the membrane are the most favorable for protein insertion, oligomerization, and eventually pore formation. To gain insight into the role of membrane properties on the functional activity of St I, we studied its binding to monolayers and vesicles of phosphatidylcholine (PC), sphingomyelin (SM), and sterols inducing (ergosterol -Erg and cholesterol -Chol) or not (cholestenone - Cln) membrane phase segregation in liquid ordered (Lo) and liquid disordered (Ld) domains. This study revealed that St I binds and permeabilizes with higher efficiency sterol-containing membranes independently of their ability to form domains. We discuss the results in terms of the relevance of different membrane properties for the actinoporins mechanism of action, namely, molecular heterogeneity, specially potentiated in membranes with sterols inducers of phase separation (Chol or Erg) or Cln, a sterol noninducer of phase separation but with a high propensity to induce nonlamellar phase. The role of the Ld phase is pointed out as the most suitable platform for pore formation. In this regard, such regions in Chol-containing membranes seem to be the most favored due to its increased fluidity; this property promotes toxin insertion, diffusion, and oligomerization leading to pore formation.

Sceptridium ternatum attenuates allergic contact dermatitis-like skin lesions by inhibiting T helper 2-type immune responses and inflammatory responses in a mouse model

BackgroundSceptridium ternatum (ST) is a medicinal herb used in folk remedies for the treatment of various disorders such as pertussis, allergic asthma, abdominalgia, diarrhea, and external use for wound healing. However, the biological and pharmacological activities of ST are not fully clarified besides anti-asthmatic effect. ObjectiveWe studied a Sceptridium ternatum ethanol extract (ST) with respect to its anti-inflammatory and immune regulatory activities in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells, concanavalin A (conA)-stimulated BALB/c mice splenocytes, and a 2,4-dinitrochlorobenzene (DNCB)-induced allergic contact dermatitis (ACD) mouse model. MethodsRAW 264.7 cells were pretreated with ST for 1h and then stimulated with LPS. To determine the anti-inflammatory effects of ST, the production of nitric oxide (NO), interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) were measured using an enzyme-linked immunosorbent assay (ELISA). To determine its anti-allergic effects, splenocytes from BALB/c mice were incubated and stimulated with conA in the absence or presence of ST for 48h. The production of IL-4 and interferon (IFN)-γ in culture supernatants were evaluated by ELISA. To test the effects of ST on ACD, 100μL of 1% DNCB was applied to the dorsal skin of BALB/c mice for 2 weeks, and ST was administered 2 h before DNCB application. The thicknesses of the epidermis and dermis were determined by skin histological analysis. Serum immunoglobulin (Ig) E levels, the production of IL-1β, IL-4, and IL-6 in dorsal skin tissue, and T helper (Th) 2 cytokines production of CD4+ T cells were analyzed by ELISA. The expression of nuclear transcription factor-κB (NF-κB) both in vitro and in vivo was determined via immunoblotting. ResultsIn RAW 264.7 cells, ST inhibited LPS-induced inflammation mediator production and NF-κB expression. ST upregulated IFN-γ production and downregulated IL-4 production in conA-stimulated splenocytes. ST application reduced the thicknesses of the epidermis and dermis by decreasing serum IgE level and the expressions of IL-1β, IL-4, IL-6, and NF-κB in the dorsal skin of the DNCB-induced ACD model mice. Furthermore, ST treated group showed reduction of the Th2 cytokines production in activated CD4+ T cells. ConclusionThese findings not only indicate that application of ST reduced skin thickening by regulating Th 2-type allergic responses and inhibiting expression of inflammatory mediators in a DNCB-induced ACD mouse model, but also suggest that Sceptridium ternatum is a natural option for the treatment of skin inflammation.

Changes in Carbohydrate Accumulation and Activities of Enzymes Involved in Starch Synthesis in Maize Kernels at Different Positions on an Ear during Grain Filling

Kernels at the upper position of a maize ear usually show slower filling rate and lower weight than those at the basal and middle positions. The mechanism is little understood. The objective of this study was to understand if changes in carbohydrate accumulation and activities of the enzymes involved in starch synthesis in the kernels at different positions on a maize ear were associated with grain filling. A maize cultivar Denghai 11 was planted in spring and summer. Contents of the soluble sugar,sucrose and starch and the activities of the adenosine diphosphoglucose pyrophosphorylase(AGPase),starch synthase(St S),and starch branching enzyme(SBE) in kernels at different positions on an ear and their relationships with grain filling rate were determined. The results showed that kernel number per ear,100-kernel weight,and grain yield were more or higher for the spring maize than for the summer maize. Although the grain yield was different between the spring maize and the summer maize,the maximum kernel filling rate,mean kernel filling rate,100-kernel weight,the contents of both soluble sugar and sucrose in kernels,the maximum starch accumulation rate and mean starch accumulation rate in kernels all exhibited an order of basal position middle position upper position. The activities of AGPase,St S,and SBE in kernels at different positions on an ear showed the changes of single peak curves,and the peak and mean enzymatic activities in kernels at the upper position were significantly lower than those at both middle and basal positions. The starch accumulation rate and kernel filling rate were very significantly and positively correlated with activities of AGPase,St S,and SBE in kernels. The results suggested that a smaller starch accumulation rate and lower weight for the kernels at the upper position on a maize ear are mainly attributed to lower activities of the enzymes involved in starch synthesis in these kernels. A higher kernel weight for the spring maize is closely associated with its stronger ability of starch synthesis in the kernels.

Biological and Histological Studies of Purified Product from Streptomyces janthinus M7 Metabolites

Fifteen clinical samples were taken out from patients suffering cancer, these patients being under the treatment with radio- and/or chemotherapy. The samples were used for the isolation of bacterial cells surrounding tumor; the samples were collected from Center of Cancer Therapy, Ain Shams University, Cairo, Egypt. The clinical bacterial isolates were purified and identified according to Bergey's manual of determinative bacteriology ninth edition (1994). The bacterial isolates were found to be Klebsiella oxytoca m1; Enterobacter cancerogenus m2; P. aeruginosa m3; Citrobacter diversus m4; Enterobacter agglomerans m5; Klebsiella oxytoca m6; Enterobacter dissolvens m7; Serratia fonticola m8; Escherichia coli m9; Citrobacter freundii m10; Staphylococcus aureus m11; Escherichia coli m12; P. aeruginosa m13; Staphylococcus aureus m14; and Bacillus cereus m15. In the present study both primary and secondary screening methods were used to screen the antibacterial activity of St. janthinus M7 against fifteen clinical bacterial isolates. The St. janthinus M7 showed an increase in antibacterial activity against all the tested human bacterial pathogens. In this study Gamma irradiation at dose levels (0.5 and 1.5 kGy) was used for the enhancement of the antibacterial activity of Streptomyces strain against the clinical isolates. Several commercial antibiotic discs (Doxorubicin, Augmentin, Norfloxacin, Ofloxacin, Oxacillin, and Cefazolin) were used for comparing their antimicrobial activity with purified product. The results declared a significant increase in the antibacterial activity in most cases. The physiochemical properties of the purified product were carried out for determination of Rf, empirical formula, M.W, and chemical structure of product and then analyzed by thin layer chromatography, elemental analysis, UV, Mass, and NMR. The result exhibited brown color, one spot, Rf (0.76), M.W (473), while it recorded 270 nm in UV region and the calculated empirical formula was (C22H19NS2O7). In in vitro antitumor activity of the purified product against human tumor cell lines (Hepg2) the IC50 was measured to be 3.0 μg/ml and in in vitro antitumor activity of purified product measured against Ehrlich ascites carcinoma (EAC) the IC50 was measured to be 33.0 μg/ml. In in vivo study of the cytotoxic effect of St. janthinus M7 purified product MYN7 was investigated. The result of histopathological alteration in female mice infected with Ehrlich tumor showed a significant effect on abnormal cells.