Exploring the impact of dexmedetomidine on short-term outcomes in critically ill sepsis-associated encephalopathy patients.

OBJECTIVE: Dexmedetomidine has demonstrated potential in preclinical medical research as a protective agent against inflammatory injuries and a provider of neuroprotective benefits. However, its effect on the short-term prognosis of patients with sepsis-associated encephalopathy remains unclear. This study aims to explore the underlying value of dexmedetomidine in these patients. PATIENTS AND METHODS: This study enrolled patients with sepsis-associated encephalopathy from the Medical Information Mart for Intensive Care (MIMIC)-IV database, and they were divided into two groups based on dexmedetomidine therapy during hospitalization. Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were utilized to balance the inter-group baseline differences. Kaplan-Meier (KM) curves with log-rank test and subgroup analysis were also employed. The primary outcome was 28-day mortality, and the secondary outcomes were in-hospital mortality, intensive care unit (ICU) stay time, hospital stay time, and the incidence of ventilator-associated pneumonia (VAP). RESULTS: After PSM, 1,075 pairs of patients were matched. In contrast to the non-dexmedetomidine cohort, the dexmedetomidine cohort did not exhibit a shortened ICU [4.65 (3.16, 8.55) vs. 6.14 (3.66, 11.04), p<0.001] and hospital stay duration [10.04 (6.55, 15.93) vs. 12.76 (7.92, 19.95), p<0.001], and there was an elevated incidence of VAP [90 (8.4%) vs. 135 (12.6%), p=0.002]. The log-rank test for the KM curves of dexmedetomidine use and 28-day mortality was statistically significant (p<0.001). The results showed that dexmedetomidine was associated with improved 28-day mortality [hazard ratio (HR) 0.46, 95% confidence interval (CI) 0.35-0.61, p<0.001] and in-hospital mortality (HR 0.50, 95% CI 0.37-0.67, p<0.001) after adjusting for various confounders. In the following subgroup analysis, dexmedetomidine infusion was associated with decreased 28-day mortality in most subgroups. CONCLUSIONS: Dexmedetomidine administration was significantly associated with reduced short-term mortality among patients with sepsis-associated encephalopathy in the ICU. However, it also prolonged ICU and hospital stays and increased the incidence of VAP.

[Clinical study on the relationship between the exosomes in bronchoalveolar lavage fluid and plasma and the severity of lung injury and outcome in early acute respiratory distress syndrome patients].

Objective: To investigate the relationship between the levels of exosomes in bronchoalveolar lavage fluid (BALF) and plasma and the severity of lung injury and its outcome in patients with acute respiratory distress syndrome (ARDS). Methods: Patients who were admitted to the Department of Critical Care Medicine, Zhongda Hospital Affiliated to Southeast University and received invasive mechanical ventilation were selected from August 2020 to April 2021, and they were divided into ARDS group and non-ARDS group. Finally, 33 ARDS patients were included, including 18 males and 15 females, aged (65.5±15.5) years; 10 non-ARDS patients, 8 males and 2 females, aged (57.2±15.3) years. The BALF and plasma of the two groups of patients were collected within 24 hours after enrollment, and the total exosomes of the samples were collected by ultracentrifugation. Nanoparticle tracking analysis (NTA) was used to detect and compare the differences in exosome content between the two groups. Correlation of content with the severity and prognosis of lung injury in ARDS patients. Results: There was no significant difference in gender and age between ARDS group and non-ARDS group (both P>0.05). The exosome in plasma of ARDS group was significantly higher than that of non-ARDS group [(25.3±1.2)/ml vs (24.2±1.6)/ml, P=0.031], while the exosomes in BALF of ARDS group was also higher than that of non-ARDS group [(26.5±1.6)/ml vs (24.6±1.1)/ml, P=0.001]. The exosomes in BALF of patients with ARDS caused by intrapulmonary causes was higher than that in ARDS group caused by extrapulmonary causes [(26.9±1.5)/ml vs (25.2±0.9)/ml, P=0.01], and the infection caused by bacterial shows that the highest exosome level in BALF. The exosomes in the BALF of the mild ARDS group was significantly lower than that of the severe ARDS group [(25.7±1.3)/ml vs (27.2±1.5)/ml, P=0.038]; the exosomes in BALF of ARDS patients was negatively correlated with P/F ratio (r=-0.38, P=0.03); and it was positively correlated with Murray lung injury score (r=0.47, P=0.01). However, the static compliance levels, length of hospital stay, duration of mechanical ventilation, and 28-day outcome were not associated with the exosomes in BALF. Conclusion: Compared with non-ARDS patients, ARDS patients have significantly higher levels of exosomes in BALF and plasma, there is a certain correlation between exosomes derived from BALF and the severity of lung injury in ARDS.

[Prevalence betel nut abuse and its related factors among residents in Haikou City from 2013 to 2014].

From 2013 to 2014, the age of 924 residents recruited in Haikou City was (38±13) years old, of which 57.3% (529) were males. Those who chewed betel nuts accounted for 17.4% (161). According to the diagnostic criteria of substance abuse in the Fourth Edition of the Diagnostic and Statistical Manual of Mental Disorders, the detection rate of betel nut abuse was 7.0% (65). Compared with those who were>30 years old, educated>6 years and non-smokers, people aged 15 to 30 years, education level less than 6 years and smoking behavior had higher risk of betel nut abuse, with the OR (95%CI) about 4.21 (1.48-11.99), 7.81 (1.92-31.69), and 13.53 (4.15-44.11), respectively.

[Clinical analysis and laboratory diagnosis of three cases with infantile botulism caused by Clostridium botulinum type B].

Objective: To summarize the clinical characteristics and laboratory diagnostic methods of infant botulism caused by Clostridium botulinum type B. Methods: Clinical data of 3 infants with type B botulism who were admitted to Children's Hospital Affiliated to Capital Institute of Pediatrics from May to November 2018 were retrospectively analyzed. Botulinum toxin was detected in fecal samples or fecal enrichment solution of the patients, and Clostridium botulinum was cultured and isolated from fecal samples. Results: The age of onset of the patients (two boys and one girl) was 3, 3 and 8 months old, respectively. Two cases had the onset in May and one case had the onset in November. There were two cases with mixed feeding and one case with breast feeding. One case's family members engaged in meat processing. All of them were previously healthy. All the children presented with acute flaccid paralysis, cranial nerve involvement and difficult defecation. Two cases had secondary urinary tract infection. Electromyograms of two cases showed that action potential amplitude of the motor nerve were lower than those of their peers. After treatments including intravenous human immunoglobulin, respiratory tract management, urethral catheterization, nasal feeding, etc., three cases recovered completely 2 to 4 months later. Type B botulinum toxin was detected in the fecal diluent of one patient, and the TPGYT enrichment solution and cooked meet medium of the feces of 3 patients, respectively. Clostridium botulinum B was identified from the feces of 3 infants after culture, isolation and purification. Conclusions: Combined with typical clinical manifestations including acute flaccid paralysis, cranial nerve involvement symptoms and difficult defecation examination, infant botulism can be clinically diagnosed. The detection of fecal botulinum toxin and the culture and isolation of Clostridium botulinum are helpful for the diagnosis.

Landing strategies focusing on the control of tibial rotation in the initial contact period of one-leg forward hops.

Anterior cruciate ligament (ACL) reconstruction (ACLR) surgeries successfully restore anterior tibial translation but not tibial rotation. This study aimed to explore landing strategies focusing on the control of tibial rotation at landing when the ACL is most vulnerable. Three groups of male subjects (50 ACLRs, 26 basketball players, and 31 controls) participated in one-leg forward hop tests for determining the tibial rotatory landing strategies adopted during the initial landing phase. The differences in knee kinematics and muscle activities between internal and external tibial rotatory (ITR, ETR) landing strategies were examined. A higher proportion of basketball players (34.6%) were found to adopt ITR strategies (controls: 6.5%), exhibiting significantly greater hopping distance and knee strength. After adjusting for hopping distance, subjects adopting ITR strategies were found to hop faster with straighter knees at foot contact and with greater ITR and less knee adduction angular displacement during the initial landing phase. However, significantly greater angular displacement in knee flexion, greater medial hamstring activities, and greater co-contraction index of hamstrings and medial knee muscles were also found during initial landing. Our results support the importance of the recruitments of medial hamstrings or the local co-contraction in assisting the rotatory control of the knee during initial landing for avoiding ACL injuries.

The performance of enhanced coagulation for treating slightly polluted raw water combining polyaluminum chloride with variable charge soil.

The feasibility and effectiveness of treating pollutants in slightly polluted raw water by variable charge soil and polyaluminum chloride (PAC) was investigated. Removal efficiencies of turbidity, phenol, aniline, algae and heavy metals (Cu(2+), Zn(2+) and Pb(2+)) were used to evaluate the coagulation performance. The results indicated that the addition of variable charge soil as a coagulant aid is advantageous due to the improvement of removal efficiencies. The tests also demonstrated that the presence of variable charge soil increased the removal of turbidity rather than adding residuary turbidity. The use of variable charge soil produced settleable flocs of greater density and bigger size. The main mechanism involved in the PAC coagulation was supposed to be sweep flocculation as well as charge-neutralization. Variable charge soil played a promoted aid role by adsorption in the enhanced coagulation process. It is concluded that the enhanced coagulation by PAC and variable charge soil, as coagulant and adsorbent, is more effective and efficient than traditional coagulation.

Cetylpyridinium chloride suppresses gene expression associated with halitosis.

OBJECTIVE: Halitosis is a common complaint affecting the majority of the population. Mouthrinses containing cetylpyridinium chloride (CPC) have been used as oral hygiene aids to suppress oral malodor. Although the clinical efficacy of these mouthrinses has been well-documented, the mechanism whereby CPC reduces malodor is less-well-understood. We hypothesized that CPC suppresses expression of the genes (mgl and cdl) and enzymes responsible for methyl mercaptan (CH3SH) and hydrogen sulfide (H2S) production by oral anaerobes associated with halitosis. In this study, the mgl and cdl expression of Porphyromonas gingivalis and Fusobacterium nucleatum in the presence of CPC was investigated. MATERIALS AND METHODS: We used a microdilution method to determine the growth and production of volatile sulfur compounds (VSCs) by P. gingivalis W83 and F. nucleatum ATCC 10953 in respective media containing CPC (0.5 µg/mL to 1.5 µg/mL). For metabolic activity, we used an XTT {2,3-bis(2-methyloxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide} reduction assay. We used real-time RT-PCR and Western blotting to evaluate the effect of CPC at sub-MIC levels on mgl and cdl expression at the transcriptional and enzymatic levels. RESULTS: CPC inhibited the growth of P. gingivalis and F. nucleatum at MICs of 3 µg/mL and 2 µg/mL, and at MBCs of 6 µg/mL and 3 µg/mL, respectively. Compared with untreated controls, CPC at 1.5 µg/mL suppressed CH3SH production of P. gingivalis by 69.84%±2.88% and H2S production of F. nucleatum by 82.55%±8.36% (p<0.05) without affecting metabolic activity. Inhibition of mgl mRNA (81.58%±20.33%) and protein (39.15%±6.65%) expression in P. gingivalis and inhibition of cdl mRNA (61.76%±13.75%) and protein (64.34%±1.62%) expression in F. nucleatum were also noted (p<0.05). CONCLUSION: CPC represents an effective agent for halitosis reduction by inhibiting the growth and suppressing the expression of specific genes related to VSC production in anaerobic periodontal pathogens.

Removal of aniline and phenol from water using raw and aluminum hydroxide-modified diatomite.

The feasibility of using raw diatomite and aluminum hydroxide-modified diatomite (Al-diatomite) for removal of aniline and phenol from water was investigated. Their physicochemical characteristics such as pHsolution, point of zero charge (pHPZC), surface area, Fourier transform infrared (FT-IR) and scanning electron microscopy was determined. After the raw diatomite was modified, the surface area of Al-diatomite increases from 26.67 to 82.65 m(2) g(-1). The pHPZC and pHsolution (10%) occurred around pH 5.2 and pH 8.6, respectively. The removal rates of aniline and phenol on diatomite and Al-diatomite decreased with increasing solution pH, while surface charge density decreased. The adsorption of aniline and phenol on diatomite presented a good fit to the Langmuir and Freundlich models, but the models are not fit to forecast the adsorption of aniline and phenol on Al-diatomite. The study indicated that electrostatic interaction was a dominating mechanism of aniline and phenol sorption onto Al-diatomite.

Single-solute and bisolute sorption of phenol and trichloroethylene from aqueous solution onto modified montmorillonite and application of sorption models.

The single-solute and bisolute sorption behaviour of phenol and trichloroethylene, two organic compounds with different structures, onto cetyltrimethylammonium bromide (CTAB)-montmorillonite was studied. The monolayer Langmuir model (MLM) and empirical Freundlich model (EFM) were applied to the single-solute sorption of phenol or trichloroethylene from water onto monolayer or multilayer CTAB-montmorillonite. The parameters contained in the MLM and EFM were determined for each solute by fitting to the single-solute isotherm data, and subsequently utilized in binary sorption. The extended Langmuir model (ELM) coupled with the single-solute MLM and the ideal adsorbed solution theory (IAST) coupled with the single-solute EFM were used to predict the binary sorption of phenol and trichloroethylene onto CTAB-montmorillonite. It was found that the EFM was better than the MLM at describing single-solute sorption from water onto CTAB-montmorillonite, and the IAST was better than the ELM at describing the binary sorption from water onto CTAB-montmorillonite.

Tea catechin EGCg suppresses the mgl gene associated with halitosis.

Epigallocatechin gallate (EGCg), the main antimicrobial tea catechin, has been reported to inhibit growth and virulence factors of oral pathogens in vitro. Although the mechanism is unclear, the potential of EGCg in reducing halitosis caused by volatile sulfur compounds (VSCs) has been suggested. This study tested the hypothesis that EGCg reduces VSCs by suppressing mgl, the gene encoding L-methionine-α-deamino-γ-mercaptomethane-lyase, responsible for methyl mercaptan (CH3SH) production by oral anaerobes. In this study, the effect of EGCg on in vitro growth, CH3SH production, and mgl gene expression in P. gingivalis W83 was investigated. EGCg inhibited growth of P. gingivalis W83 (MIC = 97.5 µg/mL) and was bactericidal (MBC = 187.5 µg/mL). At sub-MIC levels, EGCg inhibited CH3SH production, and mgl mRNA and protein expression (p < 0.05). We conclude that EGCg may represent a natural and alternative agent to the antimicrobial chemicals currently available for halitosis control.

The effect of lactoferrin on oral bacterial attachment.

INTRODUCTION: Lactoferrin (Lf), an iron-binding salivary glycoprotein, plays an important role in human innate defense against local mucosal infection. We hypothesized that Lf interferes with initial oral bacterial attachment to surfaces by iron sequestration, so inhibiting subsequent biofilm formation. The objective was to investigate the effect of Lf on the early stages of single-species and multi-species oral biofilm development. METHODS: Streptococcus gordonii, Streptococcus mutans, Fusobacterium nucleatum and Porphyromonas gingivalis were used in this study. Glass disks of a two-track flow cell coated with flowing artificial saliva (0.3 ml/min) with and without Lf (100 microg/ml) were used for studying bacterial attachment (3 h, 37 degrees C). Attachment was also examined by incubating single or multiple species of test bacteria (10(7) colony-forming units/ml) with Lf-coated (20-100 microg/ml) and uncoated glass slides. The effects of beta-lactoglobulin, 2,2'-dipyridyl (25-100 microg/ml), an iron chelator, and FeCl3 on attachment were also examined. RESULTS: Lf inhibited the initial attachment of S. gordonii (50.3%, P < 0.05) but not that of F. nucleatum and P. gingivalis. However, the attachment of a dual-species biofilm containing S. gordonii (i.e. S. gordonii/F. nucleatum or S. gordonii/P. gingivalis) was significantly reduced (48.7% or 62.1%, respectively, P < 0.05) in the presence of Lf. beta-Lactoglobulin did not affect the attachment of S. gordonii. In the presence of 100 microm 2,2'-dipyridyl, attachment of S. gordonii was reduced by 53.87%. No reduction in attachment was noted in S. gordonii pretreated with Lf (100 microg/ml) and FeCl3 (20-200 microm). CONCLUSION: Lf suppresses initial attachment of S. gordonii and S. gordonii coaggregates by iron sequestration. This may lead to subsequent inhibition of oral biofilm development.

Development of an assay for rapid identification of meat from yak and cattle using polymerase chain reaction technique.

Yak meat is of good quality with fine texture, high protein and low fat content, and rich in amino acids compared with that of cattle, and it lacks anabolic steroids or other drugs. In general terms, however, the meat yield of yak is relatively low compared with that of the cattle. In order to prevent possible adulteration of yak meat with cattle meat, based on the sequence of mitochondrial 12S rRNA gene, a multiplex PCR-based approach was proposed for rapid identification of the meat from yak and cattle using three primers designed in this work. Through the combinatorial usage of three primers with a single reaction set, two fragments of 290 and 159bp were amplified from the cattle meat DNA, whereas only a fragment of 290bp was obtained from the yak meat DNA. Using the assay described, satisfactory amplification was accomplished in the analysis of raw and heat-treated binary meat mixtures of yak/cattle with a detection limit of 0.1% for cattle meat. The technique is fast and straightforward. It might be a useful tool in the quality control of yak meat and meat products.

In situ biofilm formation by multi-species oral bacteria under flowing and anaerobic conditions.

An understanding of biofilm behavior of periodontopathic bacteria is key to the development of effective oral therapies. We hypothesized that interspecies bacterial aggregates play an important role in anaerobic biofilm establishment and proliferation, and contribute to the survivability of the biofilm against therapeutic agents. The system developed in this study assessed a multi-species (Streptococcus gordonii, Actinobacillus actinomycetemcomitans, and Fusobacterium nucleatum) biofilm formation under anaerobic and flowing conditions with the use of an in situ image analysis system. The biofilm was comprised of a base film of non-aggregated cells and complex interspecies aggregates that formed in the planktonic phase which rapidly colonized the surface, reaching 58 +/- 9% and 65 +/- 11.8% coverage by 5 and 24 hrs, respectively. Upon SDS (0.1%) treatment of a 24-hour biofilm, substantial detachment (55 +/- 14%, P < 0.05) of the aggregates was observed, while the base film bacteria remained attached but non-viable. Rapid re-establishment of the biofilm occurred via attachment of viable planktonic aggregates.

QSPR-based prediction of adsorption of halogenated aromatics on yellow-brown soil.

Halogenated aromatic compounds exist widely in soil and aqueous environment. The study of their transport and distribution is quite important for pollution control and risk assessment. In the present work the adsorption coefficients of 28 halogenated benzenes, anilines and phenols on yellow-brown soil were measured with batch equilibrium method, and a prediction model was developed through the quantitative structure-property relationship (QSPR) technique. Then the obtained model was tested with Monte Carlo simulation and Jacknife methods. The results indicated that it was robust enough to estimate soil adsorption behaviors for the tested compounds. Based on the obtained model it could be deduced that the adsorption of halogenated aromatics on yellow-brown soil was not a simple partitioning process but involved complicated interactions.

Chemical characterization of rainwater at Singapore.

A short term study of the chemical composition of rainwater was carried out from November 1999 to October 2000 in Singapore. The rainwater was typically acidic with a mean pH of 4.2. Sulfate was the most abundant ion and comparable to the results reported for other industrialized regions. The concentrations of major ions (NH(4)(+), Ca(2+), K(+), Na(+), Mg(2+), SO(4)(2+), NO(3)(2-), Cl(-), HCOO(-), CH(3)COO(-)) varied monthly. Results show that local meteorological conditions influence the chemical compositions to a significant extent. The pollutants in rainwater were derived from long range and local (industry and traffic) sources.

Evaluating biofilm growth of two oral pathogens.

AIMS: To determine the expediency of a microtitre assay system for establishing, quantifying and antimicrobial testing of two representative oral pathogens. METHODS AND RESULTS: Streptococcus mutans and Porphyromonas gingivalis were used. Morphological characteristics of the attached population were evaluated. Biofilm growth was evaluated spectrophotometrically (undisturbed and 1 N NaOH dissipated biofilm). The minimum concentration of chlorhexidine gluconate that inhibited biofilm growth was determined. Growth of the biofilms was successfully monitored by direct optical density measurements or those re-suspended in 1 N NaOH. The latter was necessary when glucans were present in Strep. mutans biofilms. The minimum concentration of chlorhexidine gluconate that inhibited biofilm growth was 1.25 microg ml(-1) for both species. The attached bacteria exhibited common biofilm characteristics. SIGNIFICANCE AND IMPACT OF THE STUDY: The assay system developed was especially useful for monitoring the growth of adherent Strep. mutans in the presence of glucans, which is particularly significant for the study of anti-plaque chemicals.

Chewing sticks: timeless natural toothbrushes for oral cleansing.

It is generally accepted that oral hygiene maintenance through regular removal of dental plaque and food deposits is an essential factor in the prevention of dental caries and periodontal disease. Methods for oral hygiene vary from country to country and from culture to culture. Despite the widespread use of toothbrushes and toothpastes, natural methods of tooth cleaning using chewing sticks selected and prepared from the twigs, stems or roots from a variety of plant species have been practised for thousands of years in Asia, Africa, the Middle East and the Americas. Selected clinical studies have shown that chewing sticks, when properly used, can be as efficient as toothbrushes in removing dental plaque due to the combined effect of mechanical cleaning and enhanced salivation. It has also been suggested that antimicrobial substances that naturally protect plants against various invading microorganisms or other parasites may leach out into the oral cavity, and that these compounds may benefit the users by protection against cariogenic and periodontopathic bacteria. Some clinical epidemiological studies are in support of this, and many laboratory investigations have suggested the presence of heterogeneous antimicrobial components extractable using different chemical procedures. A few recent studies have identified some of the active antimicrobial compounds. Today, chewing sticks are still used in many developing countries because of religion and or tradition, and because of their availability, low cost and simplicity. The World Health Organization also encourages their use. The Year 2000 Consensus Report on Oral Hygiene states that chewing sticks may have a role to play in the promotion of oral hygiene, and that evaluation of their effectiveness warrants further research.

Predicting octanol/water partition coefficient using solvation free energy and solvent-accessible surface area.

The regression model for octanol/water partition coefficients (Kow), is founded with only two molecular descriptors available through quantum chemical calculations: solvation free energy (delta Gs), and solvent-accessible surface area (SASA). For the properties of 47 organic compounds from 17 types, the model gives a correction coefficient (adjusted for degrees of freedom) of 0.959 and a standard error of 0.277 log unit. It is a suitable way to predict the partition properties that are related to solute-solvent interactions in the water phase.