Semi-rational evolution of ω-transaminase from Aspergillus terreus for enhancing the thermostability / 生物工程学报

ω-transaminase (ω-TA) is a natural biocatalyst that has good application potential in the synthesis of chiral amines. However, the poor stability and low activity of ω-TA in the process of catalyzing unnatural substrates greatly hampers its application. To overcome these shortcomings, the thermostability of (R)-ω-TA (AtTA) from Aspergillus terreus was engineered by combining molecular dynamics simulation assisted computer-aided design with random and combinatorial mutation. An optimal mutant AtTA-E104D/A246V/R266Q (M3) with synchronously enhanced thermostability and activity was obtained. Compared with the wild- type (WT) enzyme, the half-life t1/2 (35 ℃) of M3 was prolonged by 4.8-time (from 17.8 min to 102.7 min), and the half deactivation temperature (T1050) was increased from 38.1 ℃ to 40.3 ℃. The catalytic efficiencies toward pyruvate and 1-(R)-phenylethylamine of M3 were 1.59- and 1.56-fold that of WT. Molecular dynamics simulation and molecular docking showed that the reinforced stability of α-helix caused by the increase of hydrogen bond and hydrophobic interaction in molecules was the main reason for the improvement of enzyme thermostability. The enhanced hydrogen bond of substrate with surrounding amino acid residues and the enlarged substrate binding pocket contributed to the increased catalytic efficiency of M3. Substrate spectrum analysis revealed that the catalytic performance of M3 on 11 aromatic ketones were higher than that of WT, which further showed the application potential of M3 in the synthesis of chiral amines.

Structure Analysis of the Interfering Substance N-methyl-2-phenylpropan-1-amine of Methamphetamine in Wastewater / 法医学杂志

OBJECTIVES@#To analyze the chemical structure of the interfering substance that affects the result of methamphetamine analysis in wastewater.@*METHODS@#A combination of GC-MS and liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) was used to analyze the mass spectrum characteristics of the interfering substance that affects the result of methamphetamine analysis and to infer its possible structure. Liquid chromatography-triple quadrupole-mass spectrometry (LC-TQ-MS) was used to confirm the control material.@*RESULTS@#Using LC-QTOF-MS in positive electrospray ionization (ESI+) mode, the mass-to-charge ratio (m/z) of quasi-molecular ion in the MS1 mass spectrometry of interfering substance was identical to that of methamphetamine, indicating that the interfering substance was probably an isomer of methamphetamine. The MS2 mass spectra obtained at three collision energies of 15 V, 30 V and 45 V were highly similar to methamphetamine, suggesting that the interfering substance contained methylamino and benzyl groups. Further analysis using GC-MS in electron impact (EI) ionization mode showed that the base peak in the mass spectrum of the interfering substance was at m/z 44. The interfering substance was confirmed to be N-methyl-2-phenylpropan-1-amine by compared with the standard reference.@*CONCLUSIONS@#The chemical structure of N-methyl-2-phenylpropan-1-amine is highly similar to methamphetamine, which is easy to cause interference for the detection of trace amounts of methamphetamine in wastewater using LC-TQ-MS. Therefore, in the actual analysis, the chromatographic retention time can be used to distinguish between N-methyl-2-phenylpropan-1-amine and methamphetamine.

Research progress on the biomimetic remineralization of hard tooth tissues based on polyamide-amine dendrimer / 华西口腔医学杂志

Polyamide-amine (PAMAM) dendrimer, a new hyperbranched macromolecular polymer, is considered an "artificial protein" by many scholars on account of its excellent chemical and biological characteristics. PAMAM has internal cavities and a large number of reactive terminal groups. These structures allow the polymer to be used as a bionic macromoleculethat could simulate the biomimetic mineralization of the natural organic matrix on the surface of tooth tissue. Specifically, PAMAM can beused as an organic template to regulate mineral nucleation and crystal growth; thus, the polymerisa more ideal dental restoration material than traditional allogenic materials. This article reviews research progress on thePAMAM-induced biomimetic mineralization of hard tooth tissues.

Dental remineralization via poly(amido amine) and restorative materials containing calcium phosphate nanoparticles / 国际口腔科学杂志·英文版

Tooth decay is prevalent, and secondary caries causes restoration failures, both of which are related to demineralization. There is an urgent need to develop new therapeutic materials with remineralization functions. This article represents the first review on the cutting edge research of poly(amido amine) (PAMAM) in combination with nanoparticles of amorphous calcium phosphate (NACP). PAMAM was excellent nucleation template, and could absorb calcium (Ca) and phosphate (P) ions via its functional groups to activate remineralization. NACP composite and adhesive showed acid-neutralization and Ca and P ion release capabilities. PAMAM+NACP together showed synergistic effects and produced triple benefits: excellent nucleation templates, superior acid-neutralization, and ions release. Therefore, the PAMAM+NACP strategy possessed much greater remineralization capacity than using PAMAM or NACP alone. PAMAM+NACP achieved dentin remineralization even in an acidic solution without any initial Ca and P ions. Besides, the long-term remineralization capability of PAMAM+NACP was established. After prolonged fluid challenge, the immersed PAMAM with the recharged NACP still induced effective dentin mineral regeneration. Furthermore, the hardness of pre-demineralized dentin was increased back to that of healthy dentin, indicating a complete remineralization. Therefore, the novel PAMAM+NACP approach is promising to provide long-term therapeutic effects including tooth remineralization, hardness increase, and caries-inhibition capabilities.

4-Phenyl-1, 3-thiazole-2-amines as scaffolds for new antileishmanial agents

There is still a need for new alternatives in pharmacological therapy for neglected diseases, as the drugs available show high toxicity and parenteral administration. That is the case for the treatment of leishmaniasis, particularly to the cutaneous clinical form of the disease. In this study, we present the synthesis and biological screening of eight 4-phenyl-1,3-thiazol-2-amines assayed against Leishmania amazonensis. Herein we propose that these compounds are good starting points for the search of new antileishmanial drugs by demonstrating some of the structural aspects which could interfere with the observed activity, as well as suggesting potential macromolecular targets. Methods: The compounds were easily synthesized by the methodology of Hantzsch and Weber, had their purities determined by Gas Chromatography-Mass spectrometry and assayed against the promastigote forms of Leishmania amazonensis as well as against two white cell lines (L929 and THP-1) and the monkey's kidney Vero cells. PrestoBlue® and MTT viability assays were the methodologies applied to measure the antileishmanial and cytotoxic activities, respectively. A molecular modeling target fishing study was performed aiming to propose potential macromolecular targets which could explain the observed biological behavior. Results: Four out of the eight compounds tested exhibited important anti-promastigote activity associated with good selectivity indexes when considering Vero cells. For the most promising compound, compound 6, IC50 against promastigotes was 20.78 while SI was 5.69. Compounds 3 (IC50: 46.63 µM; SI: 26.11) and 4 (IC50: 53.12 µM; SI: 4.80) also presented important biological behavior. A target fishing study suggested that S-methyl-5-thioadenosine phosphorylase is a potential target to these compounds, which could be explored to enhance activity and decrease the potential toxic side effects. Conclusions: This study shows that 4-phenyl-1,3-thiazol-2-amines could be good scaffolds to the development of new antileishmanial agents. The S-methyl-5-thioadenosine phosphorylase could be one of the macromolecular targets involved in the action.(AU)

Two Cases of Corneal Edema Due to Vaporized Amine

PURPOSE: We report two cases of corneal edema in patients who presented with bilateral blurry vision due to vaporized amines while working in a polyurethane processing plant. CASE SUMMARY: A 28-year-old male presented with bilateral blurred vision. His work involved solidifying polyurethane liquid and he often found himself exposed to polyurethane heat and gas. On examination, the patient's uncorrected visual acuity (UCVA) was 20/40 (right) and 30/50 (left). A slit lamp examination revealed subepithelial microbullae in both eyes. The central corneal thickness (CCT) was also increased in both eyes, measuring 698 µm (right) and 672 µm (left). After prescribing 0.5% moxifloxacin and, 1% fluorometholone eye drops for 3 days in both eyes, the UCVA recovered to 20/40 (right) and 20/20 (left). The CCT decreased to 644 µm (right) and 651 µm (left), and the microbullae improved significantly in the left eye. The second patient was a 34-year-old female who presented with bilateral decreased visual acuity while at work. She worked in a factory that produced car seat filling. Her UCVA was 20/25 (right) and 20/20 (left). The CCT by specular microscopy was 537 µm (right) and 541 µm (left). On slit lamp examination, both eyes demonstrated bilateral central subepithelial edema. The patient did not attend any follow-up outpatient appointments after the initial presentation. CONCLUSIONS: Exposure to vaporized amines such as polyurethane may causereversible corneal toxicityeven without direct contact. Further consideration should be given to ocular safety and protection from amine compounds in the industrial field.

Synthesis and Biocompatibility Characterizations of in Situ Chondroitin Sulfate–Gelatin Hydrogel for Tissue Engineering

Novel hydrogel composed of both chondroitin sulfate (CS) and gelatin was developed for better cellular interaction through two step double crosslinking of N-(3-diethylpropyl)-N-ethylcarbodiimide hydrochloride (EDC) chemistries and then click chemistry. EDC chemistry was proceeded during grafting of amino acid dihydrazide (ADH) to carboxylic groups in CS and gelatin network in separate reactions, thus obtaining CS–ADH and gelatin–ADH, respectively. CS–acrylate and gelatin–TCEP was obtained through a second EDC chemistry of the unreacted free amines of CS–ADH and gelatin–ADH with acrylic acid and tri(carboxyethyl)phosphine (TCEP), respectively. In situ CS–gelatin hydrogel was obtained via click chemistry by simple mixing of aqueous solutions of both CS–acrylate and gelatin–TCEP. ATR-FTIR spectroscopy showed formation of the new chemical bonds between CS and gelatin in CS–gelatin hydrogel network. SEM demonstrated microporous structure of the hydrogel. Within serial precursor concentrations of the CS–gelatin hydrogels studied, they showed trends of the reaction rates of gelation, where the higher concentration, the quicker the gelation occurred. In vitro studies, including assessment of cell viability (live and dead assay), cytotoxicity, biocompatibility via direct contacts of the hydrogels with cells, as well as measurement of inflammatory responses, showed their excellent biocompatibility. Eventually, the test results verified a promising potency for further application of CS–gelatin hydrogel in many biomedical fields, including drug delivery and tissue engineering by mimicking extracellular matrix components of tissues such as collagen and CS in cartilage.

Effect of the Bis-Dimethylamino Benzydrol Coinitiator on the Mechanical and Biological Properties of a Composite

Abstract To examine the effect of the alternative coinitiator 4,4'bis dimethylamino benzydrol (BZN) in degree of conversion (DC), mechanical and biological properties of experimental composites. The coinitiator BZN was used in three concentrations (0.2, 0.5 and 1.2%), and the coinitiator DMAEMA was used as control at the same concentrations as above. The molar concentration of camphorquinone (CQ) and coinitiators was kept constant (1:1). The composites were manipulated and submitted to microhardness test (VHN), flexural and compressive strength (in MPa), elastic modulus (GPa), DC (FT-IR) and in vitro cytotoxicity (against 3T3 fibroblastic cells) of the experimental resins. Data were subjected to two-way ANOVA and Tukey post-test (α=0.05). The experimental composite resin with BZN showed higher DC values compared to control DMAEMA groups. For the mechanical properties, microhardness values were higher in BZN groups; flexural strength and elastic modulus were similar between all the groups. Compressive strength for groups BZN0.5 and DMAEMA0.5 were not statistically different, being the lowest values attributed to group BZN0.2. The experimental resins with BZN and DMAEMA were considered nontoxic against 3T3 fibroblasts. The inclusion of the coinitiator BZN in experimental composites was considered nontoxic against 3T3 fibroblast cells, without compromising DC and mechanical properties.

Resumo Analisar o efeito do co-iniciador alternativo 4,4'bisdimetilaminobenzidrol (BZN) no grau de conversão (GC) e nas propriedades mecânicas e biológicas de resinas compostas experimentais. O co-iniciador BZN foi utilizado em três concentrações (0,2, 0,5 e 1,2), e o co-iniciador DMAEMA como controle, nas mesmas concentrações acima. A concentração molar entre canforoquinona (CQ) e os co-iniciadores foi mantida constante (1:1). As resinas compostas foram manipuladas e submetidas aos testes de microdureza (VHN), resistência à compressão e flexural (em MPa), módulo de elasticidade (em GPa), GC (em %, por meio de espectroscopia micro-Raman e FTIR com KBr), citotoxicidade in vitro (frente às células fibroblásticas 3T3) das resinas experimentais. Os resultados foram submetidos ao teste ANOVA 1 fator e pós-teste de Tukey (α=0,05). As resinas compostas experimentais com o BZN apresentaram GC e propriedades mecânicas satisfatórias, além de serem consideradas atóxicas a fibroblastos 3T3. A inclusão do co-iniciador BZN à resina composta foi considerada não tóxica frente a células fibroblásticas 3T3 e sem comprometer o grau de conversão e as propriedades mecânicas da mesma.

Influence of Different Concentration and Ratio of a Photoinitiator System on the Properties of Experimental Resin Composites

Abstract The aim in this study was to evaluate the influence of different ratio of camphorquinone/tertiary amine concentration on the flexural strength (FS), elastic modulus (EM), degree of conversion (DC), yellowing (YL), water sorption (WS) and water solubility (WSL) of experimental composites. Thus, acrylate blends were prepared with different camphorquinone (CQ) and amine (DABE) concentrations and ratios by weight: (CQ/DABE%): 0.4/0.4% (C1), 0.4/0.8% (C2), 0.6/0.6% (C3), 0.6/1.2% (C4), 0.8/0.8% (C5), 0.8/1.6% (C6), 1.0/1.0% (C7), 1.0/2.0% (C8), 1.5/1.5% (C9), 1.5/3.0% (C10). For the FS and EM, rectangular specimens (7x2x1 mm, n=10) were photo-activated by single-peak LED for 20 s and tested at Instron (0.5 mm/min). Then, the same specimens were evaluated by FTIR for DC measurement. For YL, disks (5x2 mm, n=10) were prepared, light-cured for 20 s and evaluated in spectrophotometer using the b aspect of the CIEL*a*b* system. For WS and WSL, the volume of the samples was calculated (mm³). For WS and WSL, composites disks (5x0.5 mm, n=5) were prepared. After desiccation, the specimens were stored in distilled water for 7 days and again desiccated, in order to measure the WS and WSL. Data were submitted to one-way ANOVA and Tukey's test (5%). The groups C8, C9 and C10 showed higher DC, EM and YL means, compared to other composites. Therefore, the FS and WS values were similar among all groups. Also, C1, C2 and C3 presented higher WSL in 7 days, compared to other composites. In general, higher concentrations of camphorquinone promoted higher physical-mechanical properties; however, inducing higher yellowing effect for the experimental composites

Resumo O objetivo foi avaliar a influência da concentração e proporção de canforoquinona (CQ)/amina terciária (DABE) na resistência à flexão (RF), módulo flexural (MF), grau de conversão (GC), amarelamento (AM), sorpção (SA) e solubilidade em água (SL) de compósitos experimentais. Blendas acrilatas foram preparadas com diferentes concentrações e proporções de CQ/DABE em peso, como segue: (CQ/DABE%): 0,4/0,4% (C1); 0,4/0,8% (C2); 0,6/0,6% (C3); 0,6/1,2% (C4); 0,8/0,8% (C5); 0,8/1,6% (C6); 1,0/1,0% (C7); 1,0/2,0% (C8); 1,5/1,5% (C9); 1,5/3,0% (C10). Para RF e MF, espécimes retangulares (7x2x1 mm, n=10) foram fotoativados com LED de pico único (Radii Cal) por 20 s e testados em máquina Instron (0,5 mm/min). Após, o GC dos mesmos espécimes (fragmentos) foi mensurado por FTIR. Para AM, discos de compósito (5x2 mm, n=10) foram preparados, fotoativados por 20 s e imediatamente avaliados em espectrofotômetro, considerando o aspecto b do sistema CIEL*a*b*. Para SA e SL, discos de compósito (5x0,5 mm, n=5) foram preparados e seus volumes calculados (mm³). Após desidratação, as amostras foram pesadas e armazenadas em água destilada por 7 dias, pesadas e novamente desidratadas e pesadas, para se calcular o SA e SL. Os dados foram submetidos a one-way ANOVA e teste de Tukey (5%). Os grupos C8, C9 e C10 mostraram maior GC, MF e AM, comparado aos outros grupos. No entanto, RF e SA foram similares entre todos os grupos. Ainda, C1, C2 e C3 apresentaram maior SL em 7 dias comparado aos outros grupos. Em geral, maiores concentrações de CQ promoveram melhores propriedades físico-mecânicas; no entanto, levaram ao maior amarelamento dos compósitos.

Impact of drug therapy on brachioradial pruritus

Abstract: Few studies have described therapeutic options in brachioradial pruritus. We describe a cross-sectional study of brachioradial pruritus patients treated in an outpatient unit. We reviewed medical records and interviewed brachioradial pruritus patients without indication for decompressive surgery, in order to access the perceptions of intensity of pruritus prior to treatment and response to therapy. We found that antidepressants and anticonvulsants were the most frequently prescribed drugs. Best reductions in pruritus were associated with its highest intensities prior to treatment, and with longer periods of therapy.

Prophylactic use of gabapentin to reduce postoperative nausea and vomiting in patients undergoing diagnostic gynecological laparoscopy

Introduction: Postoperative nausea and vomiting [PONV] occurs in patients during the first 24 hours of the surgery. Many drugs have been used for the prevention and treatment of PONV. In this trial, we used gabapentin to evaluate its prophylactic effect in reducing the severity and incidence of PONV in patients undergoing diagnostic laparoscopic gynecological surgery

Methodology: This, double blind randomized controlled trial, was done in operation theatre complex over a period of six months. 140 patients undergoing diagnostic gynecological laparoscopic surgery were selected. Two groups were formed and 70 patients were recruited in each group using lottery method as method of randomization. Group C [control group] was given placebo medication orally two hours before surgery and group G [gabapentin group] received 600 mg of gabapentin orally two hours before the procedure. Standard general anesthesia technique was used in all patients and incidence and severity of postoperative nausea and vomiting [PONV] was recorded in these patients till 24 hours of laparoscopy

Results: Severity of PONV was graded from mild to severe. There was no PONV in 25 patients [35.7%] in group C and 47 patients [67.1%] in group G. It was mild in severity in 8 patients [11.4%] in group C and 5 patients [7.1%] in group G, moderate in 31 patients [44.3%] in group C and 15 patients[21.4%] in group G and severe PONV was seen in 6 patients [8.6%] in group C and 3 patients [4.3%] in group G [P=0.003]. Postoperative nausea and vomiting within 24 hours after procedure was present in 45 patients [64.3%] in group C and 23 patients [32.9%] in group G. Results were significant between two groups after statistical analysis with p value of 0.001

Conclusion: Administration of 600 mg of gabapentin two hours before diagnostic gynecological laparoscopy decreases the frequency and severity of PONV

Psychotropics in different causes of itch: systematic review with controlled studies

Abstract Among the wide range of symptoms neglected or resistant to conventional treatments in clinical practice, itch is emerging gradually as a theme to be studied. Itch complaints and the negative effects in the quality of life are observed in several medical fields. Although the partially obscure pathophysiology, some researchers decided to check and test the use of psychotropic drugs in resistant itch to conventional topical treatments and antihistamines. The objective of this study was to evaluate scientific evidence in psychotropic use in the treatment of itch of various causes. This is a systematic review of scientific literature. The following databases were used: PubMed, Web of Science, Scopus and Scielo. Randomized controlled trials that should focus on treatment with psychotropic drugs of pruritus of various causes were the inclusion criteria. All articles were analyzed by the authors, and the consensus was reached in cases of disagreement. Fifteen articles were included after analysis and selection in databases, with the majority of clinical trials focusing on psychopharmacological treatment of itch on account of chronic kidney disease. Clinical trials with psychotropic drugs mostly indicated significant improvement in the itching. In most trials of chronic kidney disease as basal disease for itch, greater effectiveness was observed with the use of psychotropic drugs compared with placebo or other antipruritic. However, the small amount of controlled trials conducted precludes the generalization that psychiatric drugs are effective for itch of various causes.

Gabapentin Differentially Modulate c-Fos Expression in Hypothalamus and Spinal Trigeminal Nucleus in Surgical Molar Extraction

Abstract The study on the efficacy of oral analgesics reported that no single class of drug is effective in post-surgical dental pain. Pain following removal of third molar is most commonly used and widely accepted acute pain model for assessing the analgesic effect of drugs in humans. Reports demonstrated that analgesic efficacy in the human dental model is highly predictive. The high incidence of false-negative findings in analgesic investigations hinders the process of molecular discovery. Molecular mechanism of post-surgical pain is not known. More importantly, the animal model for postoperative dental pain is not well established. In an attempt to discover an effective post-surgical dental pain blocker with acceptable side effects, it is essential to elucidate the molecular mechanism of post-operative dental pain. The present study investigated mandibular molars extraction in rat as an animal model for the post-operative dental pain in central nervous system. Using c-Fos immunohistochemistry, we demonstrated that pre administration of GBP (150 mg/kg. i.p) significantly (p< 0.01) neutralized the surgical molar extraction induced c-Fos expression bilaterally in rat hypothalamus. Present results indicate that pain after surgical molar extraction might follow novel neural pathways therefore difficult to treat with existing anti-nociceptive drugs.

Resumo O estudo da eficácia relativa dos analgésicos orais relatou que nenhuma classe única de fármaco é eficaz na dor pós-cirúrgica dental. A dor após a remoção do terceiro molar é o modelo de dor aguda mais comumente usado e amplamente aceito para avaliar o efeito analgésico de drogas em seres humanos. Os relatos demonstraram que a eficácia analgésica no modelo dental humano é altamente preditiva. A alta incidência de achados falso-negativos em investigações analgésicas dificulta o processo de descoberta molecular. O mecanismo molecular da dor pós-cirúrgica não é conhecido. Mais importante ainda, o modelo animal para a dor pós-operatória não está bem estabelecido. Numa tentativa de descobrir um bloqueador de dor dental pós-cirúrgico eficaz com efeitos secundários aceitáveis, é essencial elucidar o mecanismo molecular da dor pós-operatória dental. Neste estudo investigamos a extração de molares inferiores de ratos como modelo animal para a dor pós-operatória no sistema nervoso central. Utilizando análise imunohistoquímica de c-Fos, demonstrou-se que a administração prévia de GBP (150 mg/kg i.p) significativamente (p<0,01) neutralizou a expressão c-Fos induzida por extração molar cirúrgica bilateralmente no hipotálamo de rato. Os resultados indicam que a dor após a extração molar cirúrgica pode seguir novas vias neurais, portanto, difícil tratar com as drogas anti-nociceptivas existentes.

Effect of gabapentin pretreatment on myoclonus after etomidate: a randomized, double-blind, placebo-controlled study / Efeito do pré-tratamento com gabapentina sobre a mioclonia após etomidato: um estudo randômico, duplo-cego e controlado por placebo

Abstract Aim: To evaluate the effects of three different doses of gabapentin pretreatment on the incidence and severity of myoclonic movements linked to etomidate injection. Method: One hundered patients, between 18 and 60 years of age and risk category American Society of Anesthesiologists I-II, with planned elective surgery under general anesthetic were included in the study. The patients were randomly divided into four groups and 2 h before the operation were given oral capsules of placebo (Group P, n = 25), 400 mg gabapentin (Group G400, n = 25), 800 mg gabapentin (Group G800, n = 25) or 1200 mg gabapentin (Group G1200, n = 25). Side effects before the operation were recorded. After preoxygenation for anesthesia induction 0.3 mg kg−1 etomidate was administered for 10 s. A single anesthetist with no knowledge of the study medication evaluated sedation and myoclonic movements on a scale between 0 and 3. Two minutes after induction, 2 µg kg−1 fentanyl and 0.8 mg kg−1 rocuronium were administered for tracheal intubation. Results: Demographic data were similar. Incidence and severity of myoclonus in Group G1200 and Group G800 were significantly lower than in Group P; sedation incidence and level were appreciably higher compared to Group P and Group G400. While there was no difference in the incidence of myoclonus between Group P and Group G400, the severity of myoclonus in Group G400 was lower than in the placebo group. In the two-hour period before induction other than sedation none of the side effects related to gabapentin were observed in any patient. Conclusion: Pretreatment with 800 mg and 1200 mg gabapentin 2 h before the operation increased the level of sedation and reduced the incidence and severity of myoclonic movements due to etomidate.

Resumo Objetivo: Avaliar os efeitos de três doses diferentes de gabapentina como pré-tratamento sobre a incidência e a gravidade dos movimentos mioclônicos associados à injeção de etomidato. Método: Cem pacientes, entre 18-60 anos, estado físico ASA I-II, programados para cirurgia eletiva sob anestesia geral, foram incluídos no estudo. Os pacientes foram randomicamente divididos em quatro grupos e duas horas antes da operação receberam cápsulas orais de placebo (Grupo P, n = 25), 400 mg de gabapentina (Grupo G400, n = 25), 800 mg de gabapentina (Grupo G800, n = 25) e 1.200 mg de gabapentina (Grupo G1.200, n = 25). Os efeitos colaterais antes da cirurgia foram registados. Após pré-oxigenação para a indução da anestesia, etomidate (0,3 mg.kg−1) foi administrado por 10 segundos. Um único anestesista, cego para a medicação do estudo, avaliou a sedação e os movimentos mioclônicos com uma escala de 0 a 3. Dois minutos após a indução, fentanil (2 µgr.kg−1) e rocurônio (0,8 mg.kg−1) foram administrados para a intubação traqueal. Resultados: Os dados demográficos foram semelhantes. A incidência e a gravidade da mioclonia nos grupos G1.200 e G800 foram significativamente menores do que no Grupo P; a incidência e o nível de sedação foram consideravelmente maiores comparados com o Grupo P e o Grupo G400. Enquanto não houve diferença na incidência de mioclonia entre os grupos P e G400, a gravidade da mioclonia no Grupo G400 foi menor do que no grupo placebo. No período de duas horas antes da indução, nenhum dos efeitos colaterais relacionados à gabapentina, exceto sedação, foi observado em qualquer paciente. Conclusão: O pré-tratamento com 800 mg e 1.200 mg de gabapentina duas horas antes da operação aumentou o nível de sedação e reduziu a incidência e a gravidade dos movimentos mioclônicos associados ao etomidato.

Effect of preoperative gabapentin on pain intensity and development of chronic pain after carpal tunnel syndrome surgical treatment in women: randomized, double-blind, placebo-controlled study / Efeito da gabapentina pré-operatória na intensidade da dor e desenvolvimento de dor crônica após o tratamento cirúrgico da síndrome do túnel do carpo em mulheres: estudo randomizado duplo-cego controlado com placebo

ABSTRACT CONTEXT AND OBJECTIVES: Effective postoperative analgesia is important for reducing the incidence of chronic pain. This study evaluated the effect of preoperative gabapentin on postoperative analgesia and the incidence of chronic pain among patients undergoing carpal tunnel syndrome surgical treatment. DESIGN AND SETTINGS: Randomized, double-blind controlled trial, Federal University of São Paulo Pain Clinic. METHODS: Forty patients aged 18 years or over were randomized into two groups: Gabapentin Group received 600 mg of gabapentin preoperatively, one hour prior to surgery, and Control Group received placebo. All the patients received intravenous regional anesthesia comprising 1% lidocaine. Midazolam was used for sedation if needed. Paracetamol was administered for postoperative analgesia as needed. Codeine was used additionally if the paracetamol was insufficient. The following were evaluated: postoperative pain intensity (over a six-month period), incidence of postoperative neuropathic pain (over a six-month period), need for intraoperative sedation, and use of postoperative paracetamol and codeine. The presence of neuropathic pain was established using the DN4 (Douleur Neuropathique 4) questionnaire. Complex regional pain syndrome was diagnosed using the Budapest questionnaire. RESULTS: No differences in the need for sedation, control over postoperative pain or incidence of chronic pain syndromes (neuropathic or complex regional pain syndrome) were observed. No differences in postoperative paracetamol and codeine consumption were observed. CONCLUSIONS: Preoperative gabapentin (600 mg) did not improve postoperative pain control, and did not reduce the incidence of chronic pain among patients undergoing carpal tunnel syndrome surgery.

RESUMO CONTEXTO E OBJETIVOS: Analgesia pós-operatória eficaz é importante para reduzir a incidência de dor crônica. Este estudo avaliou o efeito da gabapentina pré-operatória na analgesia pós-operatória e na incidência de dor crônica em pacientes submetidos à cirurgia para tratamento da síndrome do túnel do carpo. DESENHO E LOCAL: Randomizado, duplo cego, Universidade Federal de São Paulo. MÉTODOS: Os 40 pacientes com 18 anos ou mais de idade foram distribuídos aleatoriamente em dois grupos: o Grupo Gabapentina recebeu 600 mg de gabapentina no pré-operatório uma hora antes da cirurgia, e o Grupo Controle recebeu placebo. Todos os pacientes receberam anestesia regional intravenosa com lidocaína a 1%. Midazolam foi utilizado para sedação, se necessário. Paracetamol foi administrado para analgesia pós-operatória, conforme necessário, e codeína, se o paracetamol fosse insuficiente. Foram avaliados: a intensidade da dor pós-operatória (durante seis meses), a incidência de dor neuropática pós-operatória (durante seis meses), a necessidade de sedação intra-operatória e o uso de paracetamol e codeína no pós-operatório. A presença de dor neuropática foi estabelecida utilizando-se o questionário DN4 (dor neuropática 4). Síndrome de dor regional complexa foi diagnosticada através do questionário Budapeste. RESULTADOS: Não foram observadas diferenças na necessidade de sedação, no controle da dor pós-operatória e na incidência de síndromes dolorosas crônicas (neuropáticas ou síndrome de dor regional complexa). Não foram observadas diferenças no consumo de paracetamol e codeína. CONCLUSÕES: Gabapentina pré-operatória (600 mg) não melhorou o controle da dor pós-operatória e não reduziu a incidência de dor crônica em pacientes submetidos à cirurgia para tratamento da síndrome do túnel do carpo.

Validation of an HPLC-UV method for the identification and quantification of bioactive amines in chicken meat / Validação de metodologia por HPLC/UV para identificação e quantificação de aminas bioativas em carne de frango de corte

A high-performance liquid chromatography with ultraviolet detection (HPLC-UV) method was validated for the study of bioactive amines in chicken meat. A gradient elution system with an ultraviolet detector was used after extraction with trichloroacetic acid and pre-column derivatization with dansyl chloride. Putrescine, cadaverine, histamine, tyramine, spermidine, and spermine standards were used for the evaluation of the following performance parameters: selectivity, linearity, precision, recovery, limits of detection, limits of quantification and ruggedness. The results indicated excellent selectivity, separation of all amines, a coefficient of determination greater than 0.99 and recovery from 92.25 to 102.25% at the concentration of 47.2mg.kg-1, with a limit of detection at 0.3mg.kg-1 and a limit of quantification at 0.9mg.kg-1 for all amines, with the exception of histamine, which exhibited the limit of quantification, of 1mg.kg-1. In conclusion, the performance parameters demonstrated adequacy of the method for the detection and quantification of bioactive amines in chicken meat.(AU)

Um método de cromatografia líquida de alta eficiência (CLAE) para pesquisa de aminas bioativas em carne de frango foi validado. Foi utilizado um sistema de gradiente de eluição com detector ultravioleta, após extração com ácido tricloroacético e derivação pré-coluna com cloreto de dansila. Os padrões de putrescina, cadaverina, histamina, tiramina, espermidina e espermina foram utilizados para avaliação dos seguintes parâmetros de desempenho: seletividade, linearidade, precisão, recuperação, limites de detecção, limites de quantificação e robustez. Os resultados mostraram excelente seletividade e separação de todas as aminas, coeficiente de determinação superior a 0,99, recuperação entre 92,25 e 105,25% na concentração 47,2mg.kg-1, limites de detecção de 0,3mg.kg-1 e limite de quantificação de 0,9mg.kg-1 para todas as aminas, com exceção da histamina, que apresentou o limite de quantificação mais alto, de 1mg.kg-1. Foi concluído que os parâmetros de desempenho demonstraram adequação do método para detecção e quantificação de aminas bioativas em carne de frango.(AU)

Treatment of patients with painful blind eye using stellate ganglion block / Tratamento de pacientes portadores de olho cego doloroso por meio de bloqueio de gânglio estrelado

BACKGROUND AND OBJECTIVES: management of pain in painful blind eyes is still a challenge. Corticosteroids and hypotensive agents, as well as evisceration and enucleation, are some of the strategies employed so far that are not always effective and, depending on the strategy, cause a deep emotional shock to the patient. Given these issues, the aim of this case report is to demonstrate a new and viable option for the management of such pain by treating the painful blind eye with the stellate ganglion block technique, a procedure that has never been described in the literature for this purpose. CASE REPORT: six patients with painful blind eye, all caused by glaucoma, were treated; in these patients, VAS (visual analogue scale for pain assessment, in which 0 is the absence of pain and 10 is the worst pain ever experienced) ranged from 7 to 10. We opted for weekly sessions of stellate ganglion block with 4 mL of bupivacaine (0.5%) without vasoconstrictor and clonidine 1 mcg/kg. Four patients had excellent results at VAS, ranging between 0 and 3, and two remained asymptomatic (VAS = 0), without the need for additional medication. The other two used gabapentin 300 mg every 12 h. CONCLUSION: currently, there are several therapeutic options for the treatment of painful blind eye, among which stand out the retrobulbar blocks with chlorpromazine, alcohol and phenol. However, an effective strategy with low rate of serious complications, which is non-mutilating and improves the quality of life of the patient, is essential. Then, stellate ganglion block arises as a demonstrably viable and promising option to meet this demand.

JUSTIFICATIVA E OBJETIVOS: o manejo da dor em olhos cegos dolorosos ainda é um desafio. Corticosteroides e hipotensores, bem como evisceração e enucleação, são algumas das estratégias até então empregadas, nem sempre eficazes e que, a depender da estratégia, causam um profundo abalo emocional no paciente. Dadas essas questões, o objetivo deste relato de caso é demonstrar uma nova e viável opção para o manejo desse tipo de dor por meio do tratamento do olho cego doloroso com bloqueios de gânglio cervicotorácico, técnica nunca descrita na literatura para esse fim. RELATO DE CASO: foram tratados seis pacientes portadores de olho cego doloroso, todos por glaucoma, nos quais a EVA (escala visual analógica para avaliação da dor em que 0 é ausência de dor e 10 é a maior dor já experimentada) variava de 7 a 10. Optou-se por sessões semanais de bloqueio de gânglio cervicotorácico com 4 mL de bupivacaína (0,5%) sem vasoconstritor e clonidina 1 mcg/Kg. Quatro pacientes apresentaram excelente resultado EVA, com variação entre 0 e 3, e dois permaneceram assintomáticos (EVA = 0), sem necessidade de medicação suplementar. Os outros dois usaram gabapentina 300 mg de 12 em 12 horas. CONCLUSÃO: atualmente, várias são as opções terapêuticas para o tratamento do olho cego doloroso, entre as quais se destacam os bloqueios retrobulbares com clorpromazina, álcool e fenol. No entanto, uma estratégia eficaz, com pequeno índice de complicações graves, não mutilante e que melhore a qualidade de vida do paciente é imprescindível. O bloqueio do gânglio cervicotorácico surge, pois, como uma opção comprovadamente viável e promissora para atender a essa demanda.

The Effectiveness of Oral Corticosteroids for Management of Lumbar Radiating Pain: Randomized, Controlled Trial Study

BACKGROUND: Although both pregabalin and gabapentin are known to be useful for treating lumbar radiating pain and reducing the incidence of surgery, the oral corticosteroids sometimes offer a dramatic effect on severe radiating pain despite the lack of scientific evidence. METHODS: A total of 54 patients were enrolled among 703 patients who complained of lumbar radiating pain. Twenty patients who received an oral corticosteroid was classified as group A and 20 patients who received the control drugs (pregabalin or gabapentin) as group B. Oswestry Disability Index (ODI), Revised Roland Morris disability questionnaire (RMDQ), Short Form 36 (SF-36) questionnaire, lumbar radiating pain, objective patient satisfaction, and objective improvement of patients or physicians were assessed at 2, 6, and 12 weeks after medication. RESULTS: No difference in the sex ratio and age was observed between the groups (p = 0.70 and p = 0.13, respectively). Group A showed greater improvement in radiating pain after 2, 6, and 12 weeks than group B (p < 0.001, p = 0.001, and p < 0.001, respectively). No differences were observed between the groups in satisfaction at the beginning and 12 weeks after taking the medication (p = 0.062 and p = 0.061, respectively) and in objective improvement of patients and physicians (p = 0.657 and p = 0.748, respectively). Group A was less disabled and had greater physical health scores than group B (p = 0.014 and p = 0.017, respectively). CONCLUSIONS: Oral corticosteroids for the treatment of lumbar radiating pain can be more effective in pain relief than gabapentin or pregabalin. The satisfaction of patients and physicians with the drug and objective improvement status were not inferior to that with gabapentin or pregabalin.

Study on biomimetic mineralization of lipopolysaccharide-amine nanopolymersomes/hyaluronic acid polyelectrolyte films on titanium surface / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To explore biomimetic mineralization of polyelectrolyte multilayer films (PEM) of gene-loaded lipopolysaccharide-amine nanopolymersomes/hyaluronic acid self assembled on titanium surface.</p><p><b>METHODS</b>Via lay-by-layer self assembly technology, PEM were constructed on titanium or quartz surface using bone morphogenetic protein-2(BMP-2) plasmid-loaded lipopolysaccharide-amine nanopolymersomes(pLNP) as a polycation, and hyaluronic acid(HA) as a polyanion. The constructed PEM were defined as substrate-pLNP-(HA-pLNP)n, where a successive deposition of HA and pLNP on substrate surface was defined as one assembly cycle, and n was the cycle number. Biomimetic mineralization on surfaces of Ti-pLNP-(HA-pLNP)4(Group A, with outermost layer of pLNP), Ti-pLNP-(HA-pLNP)4.5(Group B, with outermost layer of HA), blank control(polished titanium, Ti) and alkaline-heat treated titanium(Ti-OH) were investigated. The biomimetic mineralization was analyzed by observing the topography under field-emisssion electron microscopy(FE-SEM), characterizing the surface chemical structure and components via X-ray diffractometer(XRD) and X-ray energy disperse spectroscopy(EDS).</p><p><b>RESULTS</b>For experiment groups, XRD analysis showed that the diffraction peak of hydroxyapatite appeared, and its intensity was higher than that for Ti group. FE-SEM images showed that its surface was homogeneously covered by discrete agglomerate of big particles. EDS spectra showed that the percentage of Ca and P were 77.24% and 64.23%, and these were much higher than those in Ti group.</p><p><b>CONCLUSIONS</b>The surface of Ti-pLNP-(HA-pLNP)n is favorable for in vitro biomimetic mineralization.</p>