The therapeutic effect of controlled reoxygenation on chronic hypoxia-associated brain injury

Cardiopulmonary bypass (CPB) is the most general technique applied in congenital heart disease (CHD). However, standard CPB poses a specific pathologic condition for patients during surgery: exposure to reoxygenation. When surgery is performed on cyanotic infants, standard CPB is usually initiated at a high concentration of oxygen without consideration of cytotoxic effects. Controlled reoxygenation is defined as using normoxic CPB with a pump primed to the PO2 (oxygen tension in the blood), which is matched to the patient's preoperative saturation. The aim of this study was to determine whether controlled reoxygenation could avoid standard reoxygenation injury and also to clarify the molecular signaling pathways during hypoxia. We successfully reproduced the abnormal brain observed in mice with chronic hypoxia during early postnatal development – equivalent to the third trimester in human. Mice were treated with standard reoxygenation and controlled reoxygenation after hypoxia for 24 h. We then assessed the brain tissue of these mice. In standard reoxygenation-treated hypoxia mice, the caspase-3-dependent neuronal apoptosis was enhanced by increasing concentration of oxygen. Interestingly, controlled reoxygenation inhibited neuron and glial cell apoptosis through suppressing cleavage of caspase-3 and PARP. We also found that controlled reoxygenation suppressed LCN2 expression and inflammatory cytokine (including TNF-α, IL-6, and CXCL10) production, in which the JAK2/STAT3 signaling pathway might participate. In conclusion, our findings propose the novel therapeutic potential of controlled reoxygenation on CPB during CHD.

Summary: Controlled reoxygenation may provide an effective therapeutic strategy for hypoxia-induced tissue injury via regulation of the JAK2/STAT3 signaling pathway. It will help make better informed clinical treatment decisions for cyanotic infants.

Fifty Percent Effective Dose of Intranasal Dexmedetomidine Sedation for Transthoracic Echocardiography in Children With Cyanotic and Acyanotic Congenital Heart Disease

OBJECTIVES

To determine the 50% and 95% effective dose of intranasal dexmedetomidine sedation for transthoracic echocardiography in children with cyanotic and acyanotic congenital heart disease.

DESIGN

A prospective, nonrandomized study.

SETTING

A tertiary care teaching hospital.

PARTICIPANTS

Patients younger than 18 months with known or suspected congenital heart disease scheduled for transthoracic echocardiography with sedation.

INTERVENTIONS

Patients were divided into a cyanotic group (blood oxygen saturation <85%) or an acyanotic group (blood oxygen saturation ≥85%). This study used Dixon's up-and-down method sequential allocation design. In both groups, the initial dose of intranasal dexmedetomidine was 2 μg/kg and the gradient of increase or decrease was 0.25 μg/kg.

MEASUREMENTS AND MAIN RESULTS

The 50% effective dose (95% confidence interval) of intranasal dexmedetomidine sedation for transthoracic echocardiography was 3.2 (2.78-3.55) μg/kg and 1.9 (1.69-2.06) μg/kg in the cyanotic and acyanotic groups, respectively. None of the patients experienced significant adverse events.

CONCLUSION

The 50% (95% confidence intervals) effective doses of intranasal dexmedetomidine sedation for transthoracic echocardiography were 3.2 (2.78-3.55) μg/kg and 1.9 (1.69-2.06) μg/kg in children with cyanotic and acyanotic congenital heart disease, respectively.

Determination of the 90% effective dose of intranasal dexmedetomidine for sedation during electroencephalography in children

BACKGROUND

The intranasal route of dexmedetomidine (DEX) administration is becoming increasingly popular for providing adequate sedation during short examinations in infants and children. However, data on the 90% effective dose (ED90) of intranasal DEX are rare in children under 3 years old.

METHODS

This is a double-blind trial using a biased coin design up-and-down sequential method (BCD-UDM). Fifty-three children aged under 3 years old requiring DEX for EEG were included in our study. The first patient received 2.5 μg kg^-1 DEX, and the dose of DEX administered to the subsequent patient was determined by the response of the previous patient. The patient responses were recorded and analysed to calculate the ED90 by isotonic regression. The 95% confidence interval (CI) was estimated using a bootstrapping method.

RESULTS

Fifty-three patients were included in our study, of which 45 patients were successfully sedated, and the 8 instances of failed sedation were rescued using sevoflurane inhalation, allowing the completion of the procedure. The 90% effective dose of DEX was calculated to be 3.28 µg kg^-1 , and the 95% CI was 2.74 ~ 3.39 µg kg^-1 . No significant adverse events occurred in any of the patients.

CONCLUSION

The 90% effective dose of intranasal DEX sedation for EEG was 3.28 μg kg^-1 in children under 3 years old.

Anticonvulsant and Neuroprotective Effects of Dexmedetomidine on Pilocarpine-Induced Status Epilepticus in Rats Using a Metabolomics Approach

Background

Status epilepticus (SE) is the most extreme form of seizure. It is a medical and neurological emergency that requires prompt and appropriate treatment and early neuroprotection. Dexmedetomidine (DEX) is mainly used for its sedative, analgesic, anxiolytic, and neuroprotective effects with light respiratory depression. The purpose of this study was to comprehensively analyze the metabolic events associated with anticonvulsion and neuroprotection of DEX on pilocarpine-induced status epilepticus rats by LC-MS/MS-based on metabolomics methods combined with histopathology.

Material/Methods

In this research, rats were divided into 3 groups: a normal group, an SE group, and an SE+DEX group. Hippocampus of rats from each group were collected for further LC-MS/MS-based metabolomic analysis. We collected brains for HE staining and Nissl staining. Multivariate analysis and KEGG enrichment analysis were performed.

Results

Results of metabolic profiles of the hippocampus tissues of rats proved that dexmedetomidine relieved rats suffering from the status epilepticus by restoring the damaged neuromodulatory metabolism and neurotransmitters, reducing the disturbance in energy, improving oxidative stress, and alleviating nucleic acid metabolism and amino acid in pilocarpine-induced status epilepticus rats.

Conclusions

This integral metabolomics research provides an extremely effective method to access the therapeutic effects of DEX. This research will further development of new treats for status epilepticus and provide new insights into the anticonvulsive and neuroprotective effects of DEX on status epilepticus.

Analysis of 17 948 pediatric patients undergoing procedural sedation with a combination of intranasal dexmedetomidine and ketamine

BACKGROUND

Intranasal procedural sedation using dexmedetomidine is well described in the literature. The combination of intranasal dexmedetomidine and ketamine is a novel approach for which there are little data on the rate of successful sedation or adverse events.

OBJECTIVES

The aim of this study is to evaluate the rate of successful sedation and adverse events of intranasal procedural sedation using a combination of dexmedetomidine and ketamine for diagnostic examination in children.

METHODS

This was a retrospective study and data were collected after ethics approval. A total of 17 948 pediatric patients (7718 females, 10 230 males) in a tertiary hospital in China were evaluated. Patients received a combination of 2 μg kg^-1 of dexmedetomidine and 1 mg kg^-1 of ketamine intranasally for procedural sedation. The level of sedation and recovery was assessed by the Modified Observer Assessment of Alertness/Sedation scale and the Modified Aldrete Score.

RESULTS

The rate of intranasal sedation success was 93% (16691/17948), intranasal sedation rescue was 1.8% (322/17948), and intranasal sedation failure was 5.2% (935/17948). Sedation success was defined as successful completed the diagnostic examination and obtained adequate diagnostic-quality images and reports. Intranasal sedation success, rescue and failure were respectively defined as sedation success with intranasal a single dose, additional bolus dose and the need for intravenous (IV) medications/inhalation agents. Median sedation time was 62 min (interquartile range: 55-70 min), median time for onset of sedation was 15 min (interquartile range: 15-20 min), and median sedation recovery time was 45 min (interquartile range: 38-53 min). Incidence of adverse events was low (0.58%; 105/17948), with major and minor adverse event being reported in 0.02% (4/17948) and 0.56% (101/17948) patients, respectively. Postoperative nausea and vomiting was the most common (0.3%; 53/17948) minor adverse event.

CONCLUSION

Procedural sedation using a combination of intranasal dexmedetomidine and ketamine is associated with acceptable effectiveness and low rates of adverse events.

[Propofol combined with hypoxia induces cognitive dysfunction in immature rats via p38 pathway]

OBJECTIVE

To investigate the effects of propofol combined with hypoxia on cognitive function of immature rats and the possible role of p38 pathway and tau protein in mediating such effects.

METHODS

Ninety 7-day-old (P7) SD rats were randomized for daily intraperitoneal injection of propofol (50 mg/kg) or lipid emulsion (5.0 mL/kg) for 7 consecutive days. After each injection, the rats were placed in a warm box (38 ℃) with an oxygen concentration of 18% (hypoxia), 21% (normal air), or 50% (oxygen) until full recovery of the righting reflex. Another 90 P7 rats were similarly grouped and received intraperitoneal injections of p-p38 blocker (15 mg/kg) 30 min before the same treaments. The phosphorylated tau protein, total tau protein and p-p38 content in the hippocampus were detected using Western blotting. The spatial learning and memory abilities of the rats were evaluated with Morris water maze test.

RESULTS

Compared with lipid emulsion, propofol injection resulted in significantly increased levels of p-p38, phosphorylated tau and total tau proteins in rats with subsequent hypoxic or normal air treatment (P &lt; 0.05), but propofol with oxygen and injections of the blocker before propofol did not cause significant changes in the proteins. Without subsequent oxygenation, the rats receiving injections of propofol, with and without prior blocker injection, all showed significantly prolonged latency time and reduced platform-crossing times and third quadrant residence time compared with the corresponding lipid emulsion groups (P &lt; 0.05). With oxygen treatment, the rats in propofoland blocker-treated groups showed no significant difference in the performance in Morris water maze test from the corresponding lipid emulsion group. The results of Morris water maze test differed significantly between blocker-propofol group and propofol groups irrespective of exposures to different oxygen levels (P &lt; 0.05), but not between the lipid emulsion and blocker group pairs with exposures to different oxygen levels.

CONCLUSIONS

Propofol combined with hypoxia can affect the expression of tau protein through p38 pathway to impair the cognitive function of immature rats, in which oxygen plays a protective role.

Performance of prenatal screening using maternal serum and ultrasound markers for Down syndrome in Chinese women: a systematic review and meta-analysis

BACKGROUND

Controversies about the performance of conventional prenatal screening using maternal serum and ultrasound markers (PSMSUM) in detecting Down syndrome (DS) have been raised as a result of a recently available noninvasive prenatal test based on cell-free fetal DNA sequencing.

OBJECTIVES

To evaluate the screening performance of PSMSUM in detecting DS in Chinese women.

SEARCH STRATEGY

An exhaustive literature search of MEDLINE, Embase, the Cochrane Library, ISI Web of Science and China BioMedical Disc.

SELECTION CRITERIA

Primary studies, published from January 2004 to November 2014, which examined the screening accuracy of PSMSUM in pregnant Chinese women, compared with a reference standard, either chromosomal verification or inspection of the newborn.

DATA COLLECTION AND ANALYSIS

Data were extracted as screening positive/negative results for Down and non-Down syndrome pregnancies, allowing estimation of sensitivities and specificities. Risks of bias within and across studies were assessed. Screening accuracy measures were pooled using a bivariate random effects regression model.

MAIN RESULTS

Seventy-eight studies, involving six categories of PSMSUM, were included. Second-trimester double serum [pooled sensitivity (SEN) = 0.80, pooled specificity (SPE) = 0.95] and triple-serum (pooled SEN = 0.79, pooled SPE = 0.96) screening were the predominant PSMSUM methods. The screening performances of these methods achieved the national standard but varied enormously across studies. First-trimester combined screening (pooled SEN = 0.92, pooled SPE = 0.93) and second-trimester quadruple serum screening (median SEN = 0.86, median SPE = 0.96) performed better, but were rarely used.

AUTHOR'S CONCLUSIONS

Second-trimester maternal serum screening has the potential to achieve satisfactory screening performance in middle- and low-income countries. The reported enormous range in screening performance of second-trimester PSMSUM calls for urgent implementation of methods for performance optimization.

TWEETABLE ABSTRACT

Meta-analysis results show good accuracy of maternal serum and ultrasound screening for trisomy 21 in Chinese women.

Extensions to the Time-Oriented Database Model to Support Temporal Reasoning in Medical Expert Systems

Physicians faced with diagnostic and therapeutic decisions must reason about clinical features that change over time. Database-management systems (DBMS) can increase access to patient data, but most systems are limited in their ability to store and retrieve complex temporal information. The Time-Oriented Databank (TOD) model, the most widely used data model for medical database systems, associates a single time stamp with each observation. The proper analysis of most clinical data requires accounting for multiple concurrent clinical events that may alter the interpretation of the raw data. Most medical DBMSs cannot retrieve patient data indexed by multiple clinical events. We describe two logical extensions to TOD-based databases that solve a set of temporal reasoning problems we encountered in constructing medical expert systems. A key feature of both extensions is that stored data are partitioned into groupings, such as sequential clinical visits, clinical exacerbations, or other abstract events that have clinical decision-making relevance. The temporal network (TNET) is an object-oriented database that extends the temporal reasoning capabilities of ONCOCIN, a medical expert system that provides chemotherapy advice. TNET uses persistent objects to associate observations with intervals of time during which “an event of clinical interest” occurred. A second object-oriented system, called the extended temporal network (ETNET), is both an extension and a simplification of TNET. Like TNET, ETNET uses persistent objects to represent relevant intervals; unlike the first system, however, ETNET contains reasoning methods (rules) that can be executed when an event “begins”, and that are withdrawn when that event “concludes”. TNET and ETNET capture temporal relationships among recorded information that are not represented in TOD-based databases. Although they do not solve all temporal reasoning problems found in medical decision making, these new structures enable patient database systems to encode complex temporal relationships, to store and retrieve patient data based on multiple clinical contexts and, in ETNET, to modify the reasoning methods available to an expert system based on the onset or conclusion of specific clinical events.

Median effective dose of intranasal dexmedetomidine sedation for transthoracic echocardiography in pediatric patients with noncyanotic congenital heart disease: An up-and-down sequential allocation trial

BACKGROUND

Intranasal dexmedetomidine can provide adequate sedation during short procedures. However, previous literature investigating the single-dose use of intranasal dexmedetomidine for sedation during transthoracic echocardiography in younger children is scarce, and the effects of age on sedation with intranasal dexmedetomidine remain controversial.

OBJECTIVE

This study was to determine the 50% effective dose and estimate the 95% effective dose of single-dose intranasal dexmedetomidine to induce sedation in pediatric patients with noncyanotic congenital heart disease, and also determine the effect of age on the dose required for sedation.

METHODS

Patients were stratified into three age groups of 1-6 months, 7-12 months, and 13-36 months. Intranasal dexmedetomidine started at a dose of 2 μg kg^-1 on the first patient. The dose of dexmedetomidine for each subsequent patient was determined by the previous patient's response using Dixon's up-and-down method with an interval of 0.25 μg kg^-1 . Sedation scale and recovery were assessed by the Modified Observer Assessment of Alertness and Sedation Scale and Modified Aldrete Recovery Score. The 50% effective dose was determined by Dixon's up-and-down method. In addition, both 50% effective dose and 95% effective dose were obtained using a probit regression approach. Other variables included sedation onset time, echocardiography time, wake-up time, discharge time, heart rate, blood pressure, oxygen saturation, respiratory rate, and adverse events such as vomiting, regurgitation, and apnea.

RESULTS

The study population was comprised of 70 patients. The 50% effective dose (95% confidence interval) and the 95% effective dose (95% confidence interval) of intranasal dexmedetomidine for sedation were 1.8 (1.58-2.00) μg kg^-1 and 2.2 (1.92-5.62) μg kg^-1 in patients aged 1-6 months, 1.8 (1.61-1.95) μg kg^-1 and 2.1 (1.90-2.85) μg kg^-1 in patients aged 7-12 months, 2.2 (1.92-2.37) μg kg^-1 and 2.7 (2.34-6.88) μg kg^-1 in patients aged 13-36 months, respectively. The 50% effective dose in age group 13-36 months was higher than those of age group 1-6 months (P = .042) and 7-12 months (P = .043). There were no differences in sedation onset time, echocardiography time, wake-up time, and discharge time between groups. None of the patients experienced oxyhemoglobin desaturation, hypotension, or bradycardia during the procedure. No significant adverse events occurred.

CONCLUSION

Single-dose of intranasal dexmedetomidine was an effective agent for patients under the age of 3 years requiring sedation for transthoracic echocardiography. The 50% effective dose of intranasal dexmedetomidine for transthoracic echocardiography sedation in children aged 13-36 months was higher than in children <13 months.

Blood Pressure Is Associated with Tea Consumption: A Cross-sectional Study in a Rural, Elderly Population of Jiangsu China

OBJECTIVES

Tea has long been hypothesized to possess hypotensive effects. However, there is uncertainty regarding the association of tea consumption with arterial blood pressure (BP). We aimed to examine the association between tea consumption and BP components including systolic BP (SBP) and diastolic BP (DBP).

DESIGN

Community-based, cross-sectional study of Suzhou City, Jiangsu Province, China.

SETTING

Tea consumption has protective influence on BP and presence of hypertension.

PARTICIPANTS

4579 older adults aged 60 years or older from the Weitang Geriatric Diseases study.

MEASUREMENTS

Detailed information regarding tea consumption was collected using a pre-designed questionnaire. BP components were measured at least 3 times with a minimum 5-minute interval, by well-trained research nurses.

METHODS

Data of 4579 older adults (response rate: 82%) aged 60 years or older from the Weitang Geriatric Diseases study were included in the analysis and we estimated the relationship of tea consumption and BP using linear regression models and the association between tea consumption and risk of hypertension using logistic regression models.

RESULTS

In linear regression models, higher tea consumption frequency was found to be associated with lower systolic BP values, after adjusting for the effect of age, sex, education level, lifestyle-related factors, and cardiometabolic confounding factors in overall (coefficient =-1.49, P=0.0003), normotensive (coefficient =-0.91, P=0.017) and participants without anti-hypertensive treatment (coefficient =-1.26, P=0.027). Significant inverse association between diastolic BP and frequency of tea consumption was also observed in the overall subjects (coefficient =-0.74, P=0.003). In multivariate logistic analyses, habitual tea drinking was inversely associated with presence of hypertension [odds ratio (OR)=0.79, P=0.011] , and there was a progressive reduction in risk associated with higher frequency of tea consumption (P for trend=0.011).

CONCLUSION

Habitual tea consumption was found to be associated with lower values of components of BP and a reduced likelihood of having hypertension in older adults. Given the widespread consumption of tea throughout China and the world, together with the major cardiovascular disease risk, our findings have important implications for human health.

Development of a New Meat Analog Through Twin-Screw Extrusion of Defatted Soy Flour-lean Pork Blend

A pilot scale co-rotating, self-wiping twin-screw extruder was used to produce high-moisture texturised meat analogue products from defatted soy protein and lean pork blend with different combinations of operational variables and feed compositions. The effects of operational variables and feed compositions that include temperature setting in five heating zones of the extruder, screw speed, throughput, moisture content, oil content, and pork percentage upon sensory textual quality were determined. The optimal sensory texture and energy consumption of extrusion cooking of the feed blend were obtained with a die of rectangular slit configuration, barrel temperature setting at 60-100-120-150-110°C, screw speed at 80rpm, 50% moisture content, lean pork content ranging from 30-50%, and the oil content ranging from 12-16% (depending upon the fat content of the pork) for optimal extrudate texture formation and stable operation.

New discovery of cryptorchidism: Decreased retinoic acid in testicle

This study focuses on investigation of cryptorchidism induced by flutamide (Flu) and its histopathological damage, and detects retinoic acid concentration in testicle tissue, in order to find a new method for clinical treatment to infertility caused by cryptorchidism. Twenty SD (Sprague Dawley) pregnant rats were randomly divided into Flu cryptorchidism group (n = 10) and normal control group (n = 10). HE stained for observing morphological difference. Transmission electron microscope (TEM) was used for observing the tight junction structure between Sertoli cells. Epididymal caudal sperms were counted and observed in morphology. The expression of stimulated by retinoic acid gene 8 (Stra8) was detected using immunohistochemistry, western blot, and Q-PCR. High performance liquid chromatography (HPLC) analysis was made on retinoic acid content. Sperm count and morphology observation confirmed cryptorchidism group was lower than normal group in sperm quantity and quality. The observation by TEM showed a loose structure of tight junctions between Sertoli cells. Immunohistochemistry, western blot, and Q-PCR showed that cryptorchidism group was significantly lower than normal group in the expression of Stra8. HPLC showed that retinoic acid content was significantly lower in cryptorchid testis than in normal testis. In the cryptorchidism model, retinoic acid content in testicular tissue has a significant reduction; testicles have significant pathological changes; damage exists in the structure of tight junctions between Sertoli cells; Stra8 expression has a significant reduction, perhaps mainly contributing to spermatogenesis disorder.

Meta-analysis of association between IL-6 -634C/G polymorphism and osteoporosis

Osteoporosis is a common disease in the aging population and studies have shown that interleukin-6 (IL-6) is potentially implicated in its pathogenesis. This study was designed to assess the association between the IL-6 gene -634C/G polymorphism and osteoporosis. PubMed, Embase, China National Knowledge Infrastructure, and Wanfang databases were searched for eligible studies published up to and including December 2014 in English or Chinese. Meta-analysis was conducted by the RevMan5.2 software. Weighted mean difference and 95% confidence interval (95%CI) were calculated by a fixed-effect or random-effect model. Bone mineral density (BMD) was regarded as the assessment index. As a result, a total of four articles with 3068 subjects were included. Differences in BMD between the CC and GG genotypes were 0.03 g/cm(2) (95%CI = 0.01 to 0.05) at total body, 0.01 g/cm(2) (95%CI = 0.00 to 0.03) at femoral neck, and 0.03 g/cm(2) (95%CI = 0.00 to 0.06) at the lumbar spine (P < 0.05). For the CG versus GG genotypes, the differences in BMD were 0.03 g/cm(2) (95%CI = 0.02 to 0.05) at total body and 0.02 g/cm(2) (95%CI = 0.00 to 0.03 at the femoral neck (P < 0.05). For the CC versus CG genotypes, the differences in BMD were not significant (P > 0.05). In conclusion, the GG genotype of the -634C/G polymorphism in IL-6 appears to play a role in reducing BMD, which affects normal bone metabolism and leads to osteoporosis.

The accumulation and subcellular distribution of arsenic and antimony in four fern plants

In the present study, Pteris cretica 'Albo-Lineata' (PC), Pteris fauriei (PF), Humata tyermanii Moore (HT), and Pteris ensiformis Burm (PE), were selected to explore additional plant materials for the phytoremediation of As and Sb co-contamination. To some extent, the addition of As and Sb enhanced the growth of HT, PE, and PF. Conversely, the addition of As and Sb negatively affected the growth of PC and was accompanied with the accumulation of high levels of As and Sb in the roots. The highest concentration of Sb was recorded as 6405 mg kg(-1) in the roots of PC, and that for As was 337 mg kg(-1) in the rhizome of PF. To some degree, As and Sb stimulated the uptake of each other in these ferns. Arsenic was mainly stored in the cytoplasmic supernatant (CS) fraction, followed by the cell wall (CW) fraction. In contrast, Sb was mainly found in the CW fraction and, to a lesser extent, in the CS fraction, suggesting that the cell wall and cytosol play different roles in As and Sb accumulation by fern plants. This study demonstrated that these fern plants show a good application potential in the phytoremediation of As and Sb co-contaminated environments.