Efectividad de los desinfectantes Lysol® y Amonio Cuaternario durante la evaluación de tres áreas críticas del sillón odontológico / Antimicrobial effectiveness of Lysol® and quaternary ammonium during evaluation of three critical areas of the dental chair

Objetivo. Determinar la eficacia antimicrobiana de Lysol® y amonio cuaternario durante la evaluación de tres áreas críticas de la unidad dental (bandeja / botones de mando, respaldo del sillón odontológico y mango de la jeringa triple). Métodos. A través de un estudio experimental comparativo transversal, se analizó un universo de 8 sillones dentales: tres fueron desinfectadas con Lysol®; tres con amonio cuaternario; dos sillones se seleccionaron como controles (positivo y negativo). Todos los sillones odontológicos se muestrearon dos veces día: antes de comenzar y al finalizar su uso, durante tres días. La toma de muestras fue realizada en las Clínicas de la Universidad Hemisferios antes y después de la colocación del desinfectante; las muestras fueron transportadas en caldo de tioglicolato para ser analizadas. Se sembraron diluciones 1:2 y 1:10 de cada muestra en Agar Plate Count y se incubaron por 24 horas a 37°C. Posteriormente, se realizó un recuento de colonias por duplicado, analizándose un total de 864 muestras. Resultados. Lysol® y amonio cuaternario 5% mostraron igual efectividad antimicrobiana ante las tres áreas analizadas (p>0.05); el área en la que se halló una mayor cantidad de microorganismos fue la bandeja (incluyendo botones de mando). Conclusión. Se determinó que tanto Lysol® como amonio cuaternario 5% son altamente eficaces para eliminar los microorganismos presentes en las superficies críticas de la unidad dental; además, el área más contaminada antes del uso de los tratamientos fue la bandeja, incluyendo los botones de mando.

Objective. Determine the antimicrobial efficacy of Lysol® and quaternary ammonium during the evaluation of three critical areas of the dental unit (control tray/buttons, dental chair back, and triple syringe handle). Methods. Through a cross-sectional comparative experimental study, a total of 8 dental chairs were analyzed: three were disinfected with Lysol®, three with quaternary ammonium, and two armchairs were selected as controls (positive and negative). All dental chairs were sampled twice a day: before use and at the end of use, for three days. Sampling was carried out at the Hemisferios University Clinics before and after the application of the disinfectant. The samples were transported in thioglycollate broth for analysis. 1:2 and 1:10 dilutions of each sample were plated on Plate Count Agar and incubated for 24 hours at 37°C. Subsequently, duplicate colony counts were performed, analyzing a total of 864 samples. Results. Lysol® and 5% quaternary ammonium showed equal antimicrobial effectiveness against the three areas analyzed (p>0.05). The area with the highest number of microorganisms was the tray (including control buttons). Conclusion. It was determined that both Lysol® and 5% quaternary ammonium are highly effective in eliminating microorganisms present on the critical surfaces of the dental unit. Furthermore, the tray, including the control buttons, was found to be the most contaminated area before treatment.

Effect of a new liquid dressing of quaternary ammonium chitosan on facial laceration healing and scar inhibition / 中华医学美学美容杂志

Objective:To investigate the effect of a novel liquid dressing of quaternary chitosan on facial laceration healing and inhibition of scar formation.Methods:This study was a prospective study, including 113 cases of facial skin soft tissue laceration 52 males, 61 females, age range of 18-30 years, with mean (25.8±5.2) years in the Department of Plastic and Reconstructive Surgery, Sichuan Provincial People′s Hospital from May 2022 to February 2023. Patients were divided into two groups: the experimental group (62 cases) used quaternary ammonium chitosan rinsing wounds in the suture, and trauma spray quaternary ammonium chitosan liquid dressing in the dressing change; saline instead of an equal amount of chitosan was used to rinse wounds during the suture process and routine dressing change in the control group (51 cases). Follow-up visits were carried out in 30 d, 60 d, and 90 d postoperatively, and standardized photographs were taken preoperatively in the immediate postoperative period, before and after dressing change. The healing of the patients′ facial lacerations and patient satisfaction were recorded and assessed at the follow-up visits.Results:A total of 113 patients were included in this study, with no lost visits. During postoperative dressing change, 1 d NRS (1.03±0.18), 3 d NRS (2.69±0.53), and 5 d NRS (0.53±0.50) were lower in the experimental group than those in the control group [1 d NRS (2.35±0.59), 3 d NRS (3.27±0.75), and 5 d NRS (0.80±0.40) (all P<0.05)]. Grade A healing rate was 93.5% (58 patients) in the test group were higher than 78.4% (40 patients) in the control group (χ 2= 5.56, P<0.05); the total scores of the Vancouver Scar Rating Scale in the experimental group were lower than those of the control group at 30 d (1.65±0.48), 60 d (3.97±1.11), and 90 d (2.90±0.76) vs. 30 d (2.43 ±0.50), 60 d (5.16±1.21), and 90 d (3.55±0.78) ( t=8.48, 5.44, t=4.43; P<0.05); the overall satisfaction rate in the experimental group (93.6%) was higher than that of the control group (82.3%) (χ 2=8.16, P<0.05). Conclusions:Quaternary chitosan liquid dressing has obvious advantages in reducing wound pain, promoting wound healing, and reducing scar formation. It can improve patients′ satisfaction and worthwhile to be applied clinically.

Comparison of methods for extraction of insect fusion antifreeze protein / 中国生物制品学杂志

@#Objective To compare the concentration and protein relative yield of insect fusion antifreeze protein EGFP-OcAFP4 extracted by low temperature ethanol method,ammonium sulfate salting-out method and isoelectric point method. Methods By screening different concentrations of ethanol(5%-65%)and ammonium sulfate(0. 2-3. 0 mol/L)and different the pH values(5. 6,5. 4,5. 2,5. 0,4. 8,4. 7,4. 6,4. 5,4. 4),EGFP-OcAFP4 was extracted from the supernatant of the induced expression solution of recombinant plasmid pET28a-EGFP-OcAFP4,and detected for the purity and protein relative yield.Results When prepared by ethanol method,EGFP-OCAFP4 had the highest purity of 86. 21% at the ethanol final concentration of 30%,and the relative yield was 6. 89%;when it was prepared by ammonium sulfate salting-out,the purity was up to 42. 33% with the protein relative yield of 30. 83% at the ammonium sulfate final concentration of 2. 0 mol/L;the purity of EGFP-OcAFP4 extracted by isoelectric point method with pH of 5. 0 was the highest 15. 46%,and the relative yield was 11. 97%. Conclusion Low temperature ethanol method,ammonium sulfate salting-out and isoelectric point method can all be used for the extraction of EGFP-OcAFP4,but low temperature ethanol method and ammonium sulfate salting-out method have higher extraction purity and protein relative yield,which are more suitable for the extraction of EGFP-OcAFP4

In vitro activity comparison between anti-human T lymphocyte porcine immunoglobulin prepared by Cohn ethanol fractionation and ammonium sulphate precipitation and same type of rabbit-derived products / 中国生物制品学杂志

@#Objective To compare the in vitro activity of anti-human T lymphocyte porcine immunoglobulin(P-ATG)prepared by Cohn ethanol fractionation and ammonium sulphate precipitation,commercial rabbit anti-human thymocyte immunoglobulin(trade name:Thymoglobuline),and anti-human T lymphocyte rabbit immunoglobulin(trade name:Grafalon)so as to evaluate the properties of P-ATG prepared by two processes.Methods The four products were detected for the antibody-dependent cell-mediated cytotoxicity(ADCC)by lactate dehydrogenase(LDH)method,measured for the complement dependent cytotoxicity(CDC)by CCK-8 assay,and detected for the affinity for binding with different T cell antigens(CD3,CD4,CD8)by double immunofluorescence staining method.Results Among the four products,only Thymoglobuline at the high concentration(1 mg/mL)had a weak ADCC effect on human peripheral blood mononuclear cell(PBMC).All products could induce the CDC effect in human PBMC in a dose-dependent manner,among which the effect of Thymoglobuline was higher than that of P-ATG or Grafalon preared by two processes,about 3 to 4 times,and the effect of Grafalon was comparable to that of P-ATG.In the proportion of four products binding with T cell surface antigens CD3 and CD4 was similar,However the proportion of Thymoglobuline and Grafalon binding with CD8 antigen was slightly lower than that of P-ATG.Conclusion The in vitro activity of the P-ATG prepared by Cohn ethanol fractionation and ammonium sulphate precipitation was in good agreement,and was not lower than that of imported products at the clinical dose.

Determination of glufosinate ammonium and three metabolites in urine by ultra performance liquid chromatography-tandem mass spectrometry / 环境与职业医学

Backgroud At present, there is no unified standard for the detection of glufosinate ammonium and three metabolites in urine, which affects the accurate assessment of occupational exposure risk to a certain extent. It is of great significance to establish a rapid and effective inspection method to ensure occupational safety and public health. Objective To establish an ultra performance liquid chromatography-tandem mass spectrometry for simultaneous determination of glufosinate ammonium and three metabolites in urine. Methods The effects of dilution solvents and dilution ratios on the response values of glufosinate ammonium and three metabolites were compared, and the retention capacities of solid phase extraction columns for targets as well as the effects of chromatographic columns and mobile phase systems on chromatographic peaks were analyzed. Samples were quantified by matrix effect matching external standard method. Accuracy of the method was evaluated by recovery rate of standard addition, and precision of the method was evaluated by relative standard deviation of intra-day and inter-day measurements. Urine samples of 30 health individuals were collected to evaluate the application of the method. Results The urine samples were diluted with 0.2 mL water and 0.6 mL acetonitrile, purified by HLB solid phase extraction columns, and separated by Dikma Polyamino HILIC columns, and gradient elution was carried out with 0.5 mmol·L−1 ammonium acetate and 0.1% ammonia water as mobile phase, which achieved a good peak shape and mass spectrum response. The linearities of the four target compounds were good in the range of 0.5-50 ng·mL−1, and the correlation coefficients (r) were all greater than 0.998. The detection limits were 0.56-2.86 μg·L−1, the quantification limits were 1.87-29.54 μg·L−1, and the recovery rates of standard addition ranged from 75.0% to 103.6%, The relative standard deviations of intra-batch and inter-batch were from 2.5% to 8.1% and from 4.3% to 9.3% respectively. The method was applied to detect 30 urine samples of subjects, and no target was detected. Conclusion The method is simple, rapid, sensitive, and accurate. It is suitable for the determination of glufosinate ammonium and its metabolites in human urine without derivatization.

Synthesis and evaluation for anti-HCoV-OC43 activity of novel aloperine derivatives with different core structures / 药学学报

In this study, we designed and synthesized 12 novel aloperine derivatives with different core structures. Among them, compound 3 with a ten-membered ring core was obtained through a special ring expansion reaction after γ-H Huffman elimination of quaternary ammonium salt, and the structure was verified by X-single crystal diffraction. Furthermore, their antiviral activity against human β-coronavirus HCoV-OC43 was evaluated by CCK-8 assay. Quaternary ammonium salt 2a and 3 had a good inhibitory effect against HCoV-OC43, and 2a had the highest anti-HCoV-OC43 activity with an EC50 values of 3.77 μmol·L-1 and a SI value of over 53.1. Schrӧdinger molecular docking results showed that both 2a and 3 might display their anti-HCoV-OC43 activity by directly acting on host TMPRSS2 and SR-B1. The results expanded the structural types of endocyclic aloperine and the function against coronavirus, and provided useful scientific data for the development of pharmaceutical applications of these compounds.

Cytotoxicity evaluation, antibacterial effect, and degree of conversion of QAM-containing adhesives

Abstract The aim of this study was to evaluate the influence of adding quaternary ammonium methacrylates (QAMs) to experimental adhesives by assessing the degree of conversion (DC), cytotoxicity against keratinocytes and fibroblasts, and antibacterial activity against biofilm formation. Two QAMs were added to an experimental adhesive: dimethylaminododecyl methacrylate bromododecane (DMADDM) or dimethylaminododecyl methacrylate bromohexadecane (DMAHDM) at three concentrations each: 1, 2.5, and 5 wt.%. Experimental adhesive without QAMs (control group) and commercially available Transbond XT Primer (3M Unitek, Monrovia, California, USA) were used for comparisons. The adhesives were tested for DC, cytotoxicity against keratinocytes and fibroblasts, and antibacterial activity against biofilm formation. DC, cytotoxicity against fibroblasts, and antibacterial activity were analyzed using one-way ANOVA and Tukey's multiple comparisons. Cytotoxicity against keratinocytes was evaluated using the Kruskal Wallis and Dunn's post-hoc (α = 5%) tests. Transbond showed lower DC as compared to 5% DMAHDM, 1% DMADDM, and 5% DMADDM (p < 0.05). However, all groups presented proper DC when compared to commercial adhesives in the literature. In the evaluation of cytotoxicity against keratinocytes, Transbond induced higher viability than 2.5 wt.% groups (p < 0.05). Against fibroblasts, Transbond induced higher viability as compared to 5 wt.% groups (p < 0.05). DMAHDM at 5 wt.% reduced biofilm formation when compared to all the other groups (p < 0.05). Despite their cytotoxic effect against keratinocytes, gingival fibroblasts showed higher viability. DMAHDM at 5 wt.% decreased Streptococcus mutans viability. The incorporation of DMAHDM at 5 wt.% may be a strategy for reducing the development of white spot lesions.

Application of ammonium cerium sulfate spectrophotometry for determination of iodide in water / 中华地方病学杂志

Objective:To study the application of ammonium cerium sulfate spectrophotometry for determination of iodide in water.Methods:Ammonium cerium sulfate spectrophotometry was used to determine the iodine content of tap water and source water in the range of 0 - 20 and 0 - 200 μg/L iodine concentration. The effect of the method was verified in terms of linear range, detection limit, precision and accuracy.Results:In the range of 0 - 20 and 0 - 200 μg/L iodine concentration, the absolute values of linear correlation coefficients were > 0.999 0; the detection limits were 0.18 and 1.02 μg/L, respectively; the coefficient of variation of low, medium and high iodine concentrations in tap water and source water was less than 5%. In the range of 0 - 20 μg/L iodine concentration, the spiked recovery rates of tap water and source water were 90.33% - 110.46% and 92.21% - 102.82%, respectively; in the range of 0 - 200 μg/L iodine concentration, the spiked recovery rates of tap water and source water were 90.14% - 102.62% and 91.36% - 106.18%, respectively. The national first level standard materials GBW09113g and GBW09114g were tested, and the results of water iodine determination were within the given range of the standard materials.Conclusion:Ammonium cerium sulfate spectrophotometry has a wide linear range, high accuracy, and good precision, making it suitable for widespread application in grassroots areas.

Preparation and performance of an adhesive hemostatic dual-network hydrogel / 安徽医科大学学报

Objective@#To prepare an adhesive hemostatic hydrogel and examine its hemostatic performance and biocompatibility．@*Methods@#The precursor components were homogenously dissolved and photo-crosslinked in order to form dual-network hydrogel．The electron microscopy morphology was then analyzed ; mechanical properties were tested ; in vitro hemostatic performances were investigated by whole blood clotting test and simulation trial of cutaneous bleeding．Further，the hemocompatibility was evaluated. @*Results@#A characteristic porous network structure was presented through microscopy observation of the sample．The tensile strength of hydrogel reached 46 kPa，and strong adhesion was achieved between the hydrogel and ex vivo biological tissues．Hydrogel had significant effect on wound closure and clotting time could be shortened to 1 minute．@*Conclusion@#The hydrogel was capable of accelerating coagulation due to its ability to accumulate platelets and red cells after blood contact．The dual-network hydrogel with good hemocompatibility enabled excellent hemostatic performance by the synergistic effects of the chemical activation mechanism and physical hemostatic effect.

Research progress of bacterial biofilm eradication agents based on modifications of natural products / 药学学报

Bacterial biofilm widely exists in all kinds of bacteria, and is related to about 80 percent of bacterial infections. It is one of the main reasons for bacterial tolerance and resistance to existing antibiotics. Therefore, there is unmet clinical need for new anti-biofilm drugs. At present, there are three kinds of anti-biofilm agents under research, including biofilm inhibitors, biofilm dispersal agents and biofilm eradication agents. Among them, the biofilm eradication agent is unique, which can not only kill bacteria in biofilm but also eliminate biofilm as a monotherapy. Based on modifications of natural products with antibacterial activity, a variety of compounds with biofilm eradicating activities have been obtained, such as, acyldepsipeptides, pyrrolomycins, halogenated phenazines and halogenated 8-hydroxyquinolines. In this review, we summarize several major biofilm eradication agents above according to their structures and mechanisms.

A single-center clinical study of 61 children with ammonium urate stones / 现代泌尿外科杂志

【Objective】 To analyze the clinical characteristics of children with ammonium urate stones in Xinjiang, so as to provide reference for the prevention and treatment of this disease. 【Methods】 The clinical data of all children with ammonium urate stones admitted to the People’s Hospital of Xinjiang Uygur Autonomous Region from 2016 to 2021 were retrospectively analyzed, including age, sex, body mass index, stone site, stone size, stone component, urine pH, urine culture and biochemical examination results. The serum total protein, albumin, sodium, potassium, calcium, magnesium, uric acid and urine pH were compared between the pure and mixed groups. 【Results】 A total of 61 children (31.6%) had ammonium urate stones, their average age was (4.05±3.37) years, and the male to female ratio was 2.21∶1. Among them, there were 37 cases (60.7%) of renal calculi and 50 cases (82.0%) of upper urinary calculi. The most common component of mixed ammonium urate stones was calcium oxalate, including calcium oxalate monohydrate, calcium oxalate monohydrate and calcium oxalate dihydrate. Compared with mixed type, children with pure stone type had a younger age (P=0.001) and a smaller stone size (P=0.003). Positive urine culture was detected in 14 cases (23.0%), 7 of which (50% were infected with Escherichia coli, and 11 (78.6%) with non-urease bacteria. 【Conclusion】 Non-urease bacteria are the main pathogens of urinary tract infection in children with ammonium urate stones. The incidence is higher in boys, and the most common stone location is upper urinary tract. Calcium oxalate is the most common mixed component. Pure type is more common in young children and the stones are relatively small.

Research progress on root canal irrigation disinfection drugs / 口腔疾病防治

@#Endodontic infection control is crucial to successful root canal treatment. Irrigation is the key step in endodontic procedures, and the application of root canal irrigation and disinfection medications play an important role. How to enhance antibacterial effects and functions in removing tissues while maintaining biocompatibility is a hot topic in endodontics. Currently, insights to address this issue can be split into two categories: one, the modification or combination of conventional endodontic irrigation solutions, and two, the development of novel endodontic irrigation solutions with new technologies and materials, for instance, nanomaterials and natural exacts. However, conventional endodontic irrigation solutions, such as sodium hypochlorite and chlorhexidine, are still the first choice in clinical practice. Most novel endodontic irrigation solutions remain at the pre-clinical laboratory stage. Clinical research and relevant data are required to determine whether various methods can improve endodontic irrigation. From basic research to clinical application is the direction for advancing to the next stage. The present article focuses on research progress on endodontic irrigation, especially concerning its antibacterial mechanism, characteristics and efficacy, to provide a reference for future clinical translation.

Establecimiento de biofloc a tres relaciones carbono/nitrógeno, tendiente a la producción de zooplancton / Establishment of biofloc at three carbon/nitrogen ratios, tending to the production of zooplankton

RESUMEN El objetivo de esta investigación fue establecer el biofloc a tres relaciones carbono/ nitrógeno (C/N): 10/1, 15/1 y 20/1, determinando la secuencia de remoción de N, el perfil de sólidos y la caracterización del zooplancton, para tal fin se dispuso de tres tanques con volumen de 7000 L, incorporando oxígeno al agua a través de un aireador tipo soplador. Se utilizó como fuente de N balanceado, fuente de carbono melaza y bicarbonato de sodio como fuente alcalinizante. Al inicio se incrementó el nitrógeno amoniacal total NAT a 2 mg/L, la alcalinidad total (AT) a 120 mg/L y se adicionó como inóculo 10 litros/tanque de agua proveniente de un estanque de cultivo, al sexto y décimo días se adicionó balanceado incrementando teóricamente el NAT en 4 mg/L y a partir del día 12 en 1 mg/L. En las tres relaciones C/N se evidenciaron procesos de nitrificación durante la estabilización del biofloc, hasta llegar en el tiempo a concentraciones no letales de amonio y nitrito para peces, menores a 1 mg/L. En cuanto a los sólidos volátiles, se encontró una mayor concentración en la relación 20/1, lo cual puede atribuirse a la mayor adición de melaza, con la consecuente producción de SSV a partir de la dominancia de comunidades heterotróficas, en los tres macrocosmos se presentaron comunidades del zooplancton, no obstante, el T2 presentaron la mayor abundancia y riqueza de organismos. Las tres relaciones C/N en biofloc establecieron condiciones de calidad de agua y alimento vivo.

ABSTRACT The objective of this research was to establish the biofloc at three carbon/nitrogen (C/N) relationships: 10/1, 15/1 and 20/1, determining the N removal sequence, the solids profile and the characterization of the zooplankton, for this purpose three tanks with a volume of 7000 L were available, incorporating oxygen into the water through a blower-type aerator. It was used as a source of balanced N, a source of carbon molasses and sodium bicarbonate as an alkalizing source. At the beginning, the total ammoniacal nitrogen NAT was increased to 2 mg/L, the total alkalinity (AT) to 120 mg/L and 10 liters / tank of water from a culture pond was added as inoculum, on the sixth and tenth days it was he added balanced, theoretically increasing the NAT by 4 mg/L and from day 12 by 1 mg/L. In the three C / N relationships, nitrification processes were evidenced during the stabilization of the biofloc, until reaching non-lethal concentrations of ammonium and nitrite for fish, less than 1 mg/L in time. Regarding volatile solids, a higher concentration was found in the 20/1 ratio, which can be attributed to the greater addition of molasses, with the consequent production of SSV from the dominance of heterotrophic communities, in the three macrocosms there were Zooplankton communities, however, T2 presented the highest abundance and richness of organisms. The three C / N relationships in biofloc established conditions of water quality and live food.

Simultaneous determination of seven constituents in Chenxiang Lubailu tablet by HPLC / 药学实践与服务

Objective To establish the method for the simultaneous determination of liquiritin, ammonium glycyrrhizinate, hesperidin, nobiletin;tangeretin;costunolide, dehydrocostuslactone in Chenxiang Lubailu tablet by HPLC. Methods ZORBAX Eclipse XDB-C18 chromatographic column (4.6 mm×250 mm, 5 μm) was used. The mobile phase was methanol-0.1% phosphoric acid solution. Gradient elution with flow rate of 1.0 ml/min was used. Column temperature was 35 ℃. Detection wavelength for liquiritin, ammonium, tangeretin, and costunolide was at 237 nm. Detection wavelength for glycyrrhizinate was at 283 nm. Detection wavelength for hesperidin and nobiletin was at 330 nm. Injection volume was 10 μl. 16 batches of samples were tested. Results The linear ranges for the detection of liquiritin, ammonium, glycyrrhizinate, hesperidin, nobiletin, tangeretin, and costunolide were 1.110 - 55.72 (r=0.9992), 22.15 - 1108 (r=0.9999), 6.140 - 307.2 (r=0.9995), 1.130 - 56.25 (r=0.9997), 0.3700 - 18.75 (r=0.9982), 0.5200 - 26.01 (r=0.9991), and 1.180 - 58.95 (r=0.9999) μg/ml respectively. The average recoveries were 98.71%, 98.12%, 98.44%, 98.22%, 99.17%, 99.18%, and 97.93%, and the RSDs were 0.16%, 0.67%, 0.57%, 0.62%, 0.48%, 0.56%, and 0.58% respectively. The contents of the seven components in 16 batches of samples were 0.1250 - 1.174, 2.354 - 7.426, 1.822 - 27.21, 0.0370 - 1.399, 0.0723 - 0.4433, 0.0140 - 0.1990, and 0.2207 - 1.407 mg/g respectively. Conclusion The method is accurate, reproducible and durable, which could be used to the quality control and evaluation of Chenxiang Lubailu tablet.

Determination of arsenic in urine by hydride generation atomic fluorescence spectrometry with ammonium persulfate digestion / 中华地方病学杂志

Objective:To establish a hydride generation atomic fluorescence method using ammonium persulfate as the digestion reagent for determination of arsenic in urine (hereinafter referred to as this method).Methods:The collected urine samples with ammonium persulfate were heated and digested on the tubular electric heating automatic control constant temperature digester (60 holes), with 5% hydrochloric acid solution as reaction medium and current carrier and 1.5% potassium borohydride solution as reducing agent. Arsenic content was determined with a four-channel atomic fluorescence spectrometer. The arsenic standard solution of 0 - 10 μg/L was prepared to determine the standard curve of this method, and the method was evaluated from the detection limit, linear range, correlation coefficient, precision, standard addition recovery experiment, and urine arsenic quality control sample detection. The standard method "Determination of Arsenic in Urine by Hydride Generation Atomic Fluorescence Spectrometry" (WS/T 474-2015, referred to as the standard method) was used for comparison experiments.Results:When the sampling volume was 1 ml, the detection limit of this method (digest with 1 ml 1.5 mol/L ammonium persulfate) was 0.03 μg/L. In the range of arsenic content from 0 - 10 μg/L, the linear relationship between arsenic content and fluorescence intensity was good, and the correlation coefficients ( r) were all 0.999 9. The relative standard deviations( RSD) of the three replicates of urine samples with different concentrations were 1.00%, 0.89% and 0.49%, respectively. Urine arsenic quality control samples were tested, and the test results were all within the range of public values; the overall average recovery was 102.29%, and the recovery range was 92.10% - 108.15%. Compared with the standard method in the determination results of 20 urine samples, the difference was not statistically significant ( t = - 0.40, P > 0.05). Conclusions:The hydride generation atomic fluorescence spectrometry using ammonium persulfate as digestion reagent for the determination of arsenic in urine has the advantages of low detection limit, good precision, high accuracy, small amount of sampling and digestion reagent, simple operation, and less harmful gas generation in sample pretreatment. It is suitable for rapid determination of arsenic in urine in large quantities.

Evaluation of current disinfection practice of transvaginal ultrasound probes in a Philippine Tertiary Referral Hospital: A comparative study on the performance of manual reprocessing methods

Objectives@#There are no standard infection control regulations in transvaginal ultrasound probe disinfection followed in the most prominent local public tertiary referral hospital. Likewise, no studies have evaluated the efficacy of the current method that uses an inexpensive multipurpose antiseptic spray solution. This study aims to evaluate the efficacy of the current practice of manual disinfection of TVS probes and compare it with the performance of an acceptable manual reprocessing method. @*Methods@#A prospective, randomized, controlled study was carried out using a crossover, quasi-experimental design, collecting 119 total samples from the ultrasound transducers before (35 samples) and after disinfection with two manual reprocessing methods, either a locally manufactured multipurpose antiseptic spray (A-Septic® Multipurpose Antiseptic Spray) that is currently used for disinfection or Mikrozid Sensitive®, a ready to use impregnated wipes (42 samples each arm). Disinfection efficacy was evaluated based on microbial culture results. @*Results@#Before disinfection, bacterial growth was observed in 77.1% (27/35) of the probes. After disinfection, 80.95% (34/42) remained contaminated with the antiseptic spray and 21.43% (9/42) with the wipes. The cultures revealed many environmental and pathogenic bacterial isolates, including Burkholderia, Staphylococcus, Acinetobacter, Diphtheroids, and Pseudomonas. @*Conclusions@#The currently used method for disinfecting transvaginal transducers in the division is not adequate for decontamination and decreasing the risk of cross contamination among patients. The results call for aggressive disinfection measures and highlight the need to update local standards and formulate and institutionalize these recommendations.

Resistencia antimicrobiana y daño al medio ambiente, en el contexto COVID-19: Una revisión sistemática / Antimicrobial resistance and damage to the environment, in the context of COVID-19: A systematic review

Las pautas de abordaje de los pacientes con COVID-19, al inicio de la pandemia, se realizó por ensayo, ya que se desconocía la fisiopatología de esta nueva enfermedad, entre las acciones médicas se describió el uso de antiboticoterapias de manera indiscriminada, también se instó a realizar desinfección profundas, muchas veces, con sustancias químicas con impacto negativo en la salud ambiental, tanto a nivel de la microbiota encargada del equilibrio ecológico, como en la contaminación ambiental, principalmente del agua. Aunado a esto, debido a la emergencia sanitaria, se requirió usar en mayor cantidad equipos de protección personal de un solo uso y, como consecuencias el aumento de desechos sólidos peligrosos, cuya composición son de degradación tardía. Por tanto, la respuesta sanitaria ante la pandemia, probablemente fue escenario para acentuar la resistencia antimicrobiana y el riesgo de daño ambiental. En este, artículo se realizó una revisión sistemática de la literatura científicas en torno a estos tópicos, las evidencias demostraron el aumento de mecanismos de resistencias de bacterias, principalmente, patógenas del tracto respiratorio. De igual manera, el impacto negativo por uso irracional de desinfectantes químicos, traducido en bacterias resistentes especialmente a compuestos de amonio cuaternario. La bioacumulación y biomagnificación de estas sustancias ha provocado toxicidad, mutaciones, propagación de genes de resistencia. Por lo tanto, se sugiere que se priorice las estrategias que mitiguen el rastro que ha venido extendiéndose al paso de la pandemia por el SAR- CoV-2(AU)

The guidelines for the approach of patients with COVID-19, at the beginning of the pandemic, were carried out by trial, since the pathophysiology of this new disease was unknown, among the medical actions the use of antibiotic therapies indiscriminately was described, also the urged to carry out deep disinfection, many times, with chemical substances with a negative impact on environmental health, both at the level of the microbiota responsible for the ecological balance, and in environmental pollution, mainly of water. In addition to this, due to the health emergency, it was required to use more single-use personal protective equipment and, as a consequence, the increase in hazardous solid waste, whose composition is delayed degradation. Therefore, the health response to the pandemic was probably the setting to accentuate antimicrobial resistance and the risk of environmental damage. In this article, a systematic review of the scientific literature on these topics was carried out, the evidence demostrated the increase in resistance mechanisms of bacteria, mainly pathogens of the respiratory tract. Anyways, the negative impact due to the irrational use of chemical disinfectants, translated into resistant bacteria, especially to quaternary ammonium compounds. The bioaccumulation and biomagnification of these substances has caused toxicity, mutations, propagation of resistance genes. Therefore, it is suggested that strategies be prioritized that mitigate the trail that has been spreading as the pandemic passed by SAR-CoV-2(AU)

Use of ammonium chloride to prevent urolithiasis in sheep / [Utilização do cloreto de amônio na prevenção de urolitíase em ovinos]

Urolithiasis has a high incidence among confined sheep. It is multifactorial and may cause economic damage. Our aim was to determine the capacity of urinary acidification using ammonium chloride in sheep. Twenty-five 3-month-old male sheep were confined and randomly divided into three groups; the G200 and G500 groups received 200mg/kg/GW and 500mg/kg/GW of ammonium chloride daily for 56 consecutive days, respectively, whereas the CG group did not receive ammonium chloride. Sampling times and clinical evaluation were performed weekly, starting from the 14th day of confinement (M1 or immediately before administering ammonium chloride) until the 17th day (M9) of the feedlot. Hemogasometry, biochemical examination of serum urea and creatinine concentration and ultrasound evaluation of the urinary tract were performed. The urinalysis indicated a higher incidence of ammonium magnesium phosphate crystals at the beginning of the study, showing a migration to urate crystal formation, mainly in the G500 group because of urinary acidification. No hemogasometric, serum biochemistry, ruminal fluid, or ultrasonographic changes were observed. Urinary acidification was achieved and maintained after M7 during the administration of ammonium chloride in the G500 group, but not in the other study groups.(AU)

A urolitíase apresenta alta incidência em ovinos confinados, etiologia multifatorial, e pode causar prejuízo econômico. O objetivo do presente estudo foi determinar a capacidade da acidificação urinária mediante o uso de cloreto de amônio em ovinos. Foram utilizados 25 ovinos de três meses de idade, confinados e divididos aleatoriamente em três grupos: grupo CG (controle) não recebeu cloreto de amônio; grupo G200 (200mg/kg/PV) recebeu cloreto de amônio por 56 dias consecutivos; grupo G500 (500mg/kg/PV) recebeu cloreto de amônio por 56 dias consecutivos, administrados diariamente por via oral. Os momentos (M) de colheita de amostras e de avaliação clínica foram realizados com intervalo de sete dias, sendo M1 (imediatamente antes do cloreto de amônio), M2 (sete dias após) até M9, totalizando 70 dias de confinamento. Foram realizadas hemogasometria, concentração sérica de ureia e creatinina e avaliação ultrassonográfica do trato urinário. Na urinálise, houve uma maior incidência de cristais de fosfato amônio magnesiano no início do estudo, com migração para formação de cristais de urato, principalmente no G500, devido à acidificação urinária. Não houve alterações hemogasométricas, na bioquímica sérica, no líquido ruminal, ou alterações ultrassonográficas. A acidificação urinária foi obtida e mantida a partir do M7 durante a administração do cloreto de amônio no grupo G500, não ocorrendo nos outros grupos de estudo.(AU)

Polifluoruro de amonio como alternativa de acondicionamiento para laminados ultradelgados de disilicato de litio. Reporte de caso / Ammonium polyfluoride as an alternative for the surface conditioning of ultrathin lithium disilicate veneers. A case report

RESUMEN: Los laminados vitrocerámicos ultradelgados constituyen una alternativa conservadora para la resolución de alteraciones estéticas. Sin embargo, su acondicionamiento con ácido fluorhídrico suele no estar exento de complicaciones, por lo que el uso de un sistema autograbante en base a polifluoruro de amonio (Monobond Etch&Prime, MEP) permite disminuir el riesgo de sobregrabado, simplificando la técnica. El presente reporte presenta el seguimiento a dieciocho meses de un caso clínico resuelto mediante laminados vitrocerámicos acondicionados únicamente con MEP. Caso. Paciente joven con alteraciones estéticas en el sector anterosuperior. Se realizaron preparaciones conservadoras para la confección de laminados ultradelgados en disilicato de litio (e.maxPress). Las vitrocerámicas fueron acondicionadas sólo con MEP y se cementaron con Variolink Esthetic LC. Al año y medio las restauraciones se observaron indemnes, manteniendo un buen ajuste marginal y ausencia de tinciones. Conclusiones. MEP aparece como una alternativa prometedora para reemplazar al ácido fluorhídrico en la cementación de laminados vitrocerámicos.

ABSTRACT: Ultrathin glass-ceramic veneers are a conservative approach for the restorative treatment of aesthetic disorders in the anterior region. However, surface conditioning with hydrofluoric acid of the thin structures can be usually a challenging step. Therefore, the use of a self-etching ceramic primer containing ammonium polyfluoride (Monobond Etch&Prime, MEP) offers a simplified technique with a reduced risk of overetching. Here we present an 18-month follow-up of ultrathin glass-ceramic veneers conditioned with MEP only. Case. Young female patient with an aesthetic disorder in the front region. The four upper incisors were conservatively prepared for ultrathin lithium disilicate (e.maxPress) veneers. Pre-treatment of the glass-ceramics consisted only of MEP application, followed by adhesive cementation with Variolink Esthetic LC. At the 1.5-year recall, the restorations appeared undamaged, with no marginal gap or staining. Conclusions. MEP constitutes a promising alternative to hydrofluoric acid for the adhesive cementation of glass-ceramic veneers.

Improved synthetic process of apremilast / 中国药科大学学报

@#To optimize the process of hydrogenation reduction in the synthesis of apremilast (APST), 3-nitrophthalic anhydride (4) and (S)-1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl) ethanamine-(S)-2-acetamido-4-methylpentanoate (7) were used as starting materials to synthesize (S)-2-(1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethyl)-4-nitroisoindoline-1,3-dione (8) by amination.Then compound 8 was reduced to (S)-4-amino-2-(1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl) ethyl) isoindoline-1,3-dione (9) with ammonium formate as hydrogen source and palladium hydroxide as catalyst.Finally, apremilast was obtained by the acetylation reaction with acetic anhydride.The structure of the products were verified by optical rotation, 1H NMR, 13C NMR, MS and elemental analysis.And the total yield of three steps was increased to 67.0%.The improved reduction process can avoid the special reaction of hydrogenation and pressurization, and reduce the safety risk and production costs with high commercial value.