Due to their persistence or continuous discharge, toxic substances are present in the aquatic environment, and can bioaccumulate and biomagnify in the food web, generating a significant ecological risk and a threat to human health. The present study assess the occurrence and tissue (muscle, liver, stomach and gills) distribution of 59 anthropogenic contaminants of emerging concern (CECs) in marine fish from Brazil. A simpler and faster analytical methodology based on vortex-assisted matrix solid-phase dispersion (VA-MSPD) and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was developed and validated. Limits of quantification ranged from 3.31 to 114 ng g-1 dw with recovery rates between 60 and 140 % and relative standard deviation below 20 %. The ultraviolet filters 4-hydroxybenzophenone (4HB) (benzophenone-3 metabolite) and benzocaine (Et-PABA), and the antibacterial salicylic acid were frequently accumulated in muscle and liver at concentrations between 39.5 and 21.0 ngg-1 dw. The determined concentrations resulted to be lower than the tolerable daily intake recommended by the European Food Safety Authority (EFSA).

Nanofibers (NFs) can be encapsulated with cyclodextrins (CDs) based host-guest complexes (HCs) in order to enable many biological applications. Here, benzocaine (BNZ) forms HCs with β-cyclodextrin (β-CD) that are co-precipitated and further added to polyacrylonitrile (PAN) solution for making BNZ:β-CD-HCs/PAN NFs material with the aid of electrospinning technique. The marginal increase in absorbance and fluorescence intensity along with the shift in spectral maxima of BNZ in the presence of β-CD suggested the host-guest interaction between BNZ and β-CD. NFs showed a uniform and clean morphology in SEM images and interestingly, the ICs revealed that significantly thinner in terms of average fiber diameter (AFD) than those of free BNZ on PAN medium. BNZ molecule is completely included in the PAN surface as the result of NFs and thus, the original sharp peaks for the BNZ have vanished and the peaks are much broader for the BNZ and BNZ:β-CD-HCs. BNZ is also found to be a good candidate for anti-inflammatory, anti-oxidant, and anti-diabetic. The results showed an improved activity when it is in the form of HCs on a PAN medium. Making HCs of drugs could be significant in biological applications.

Local anesthesia is essential for pain control in dentistry. The authors assessed the comparative effect of local anesthetics on acute dental pain after tooth extraction and in patients with symptomatic irreversible pulpitis.

Dapsone is used in the treatment of a variety of dermatological conditions and prophylaxis of opportunistic infections. However, if consumed at a dose of more than 200 mg/day, it can cause methemoglobinemia, a condition characterized by elevated methemoglobin levels in the blood; methemoglobin is an abnormal form of hemoglobin, containing iron in the ferric state (Fe3 +) rather than the reduced ferrous form (Fe2 +) found in hemoglobin. A small amount of it is produced in the body due to oxidant damage to the red blood cells. Methemoglobinemia can cause varied clinical manifestations involving the cardio-respiratory and nervous systems depending upon the level of methemoglobin. While it could be congenital, it is commonly caused by exposure to drugs that cause oxidation of hemoglobin, such as benzocaine, dapsone, and nitrates. We report a case of dapsone-induced methemoglobinemia in a previously healthy young female who had consumed 15 tablets of dapsone 100 mg with suicidal intent. She presented with central cyanosis, breathlessness, and altered sensorium after five days of consumption. While the pulse-oximeter showed oxygen saturation (SaO2) of 84%, arterial blood gas (ABG) analysis showed partial pressure of oxygen (PaO2) of 427 mmHg and SaO2 of 98%. This "saturation gap" occurred due to the presence of the abnormal hemoglobin variant. Her cyanosis did not improve despite giving 100% supplemental oxygen. There was no cardiac or respiratory cause to account for her cyanosis. Her methemoglobin level was 45.8%. She was successfully treated with specific antidote methylene blue, mechanical ventilation, and other symptomatic measures. The purpose of this presentation is to help clinicians recognize this condition early, because, if left untreated, it might prove fatal. The diagnostic clues include refractory hypoxemia, central cyanosis in the absence of cardiac and respiratory causes, saturation gap, and chocolate-colored blood.

Edible bird's nest (EBN) is a popular and expensive food material. The limited supply and great demand result in the use of adulterants. The authenticity concern is raised due to the lack of appropriate quality markers. Herein, this study aims to provide a specific oligosaccharide marker for rapid EBN authentication. Comparing the benzocaine (ABEE)-labeled saccharide profiles of multiple batches of EBN and adulterants indicates seven unique EBN oligosaccharides. The most abundant one, named BNM001, was selected as a marker and characterized to be Neu5Ac (2-3) Gal by MS and NMR spectra. This new oligosaccharide marker enables a rapid authentication of EBN within 10 min. ABEE labelling of this marker further upgraded the accuracy and sensitivity of the LC-qTOF-MS quantitative analysis. The relative marker content was associated with the quality of EBN products. These results suggest a specific and efficient quality marker for rapid authentication of EBN and related products.

Inflammatory diseases of the pharynx occupy one of the leading places in the structure of otorhinolaryngological pathology. Acute and chronic inflammatory processes in the pharynx, as well as exacerbations of the latter, are faced by doctors of a wide range of specialties. Oropharyngeal swab laboratory testing is required to identify a specific pathogen, which takes time. In this regard, of particular interest are local drugs with the necessary spectrum of action, the use of which is possible, both as monotherapy and in combination with systemic therapy. The combination of tyrothricin (tyrothricin), benzalkonium chloride (benzalkonium chloride), and benzocaine (benzocaine) (dorithricin) is highly effective in the treatment of bacterial, viral and fungal infections of the pharynx, and microorganisms consistently demonstrate high sensitivity to the components of the drug.

Agarose (AG) is a naturally occurring biocompatible marine seaweed extract that is converted to hydrocolloid gel in hot water with notable gel strength. Currently, its mucoadhesion properties have not been fully explored. Therefore, the main aim of this study was to evaluate the mucoadhesive potential of AG binary dispersions in combination with Carbopol 934P (CP) as mucoadhesive gel preparations. The gels fabricated via homogenization were evaluated for ex vivo mucoadhesion, swelling index (SI), dissolution and stability studies. The mucoadhesive properties of AG were concentration dependent and it was improved by the addition of CP. Maximum mucoadhesive strength (MS) (27.03 g), mucoadhesive flow time (FT) (192.2 min), mucoadhesive time in volunteers (MT) (203.2 min) and SI (23.6% at 4 h) were observed with formulation F9. The mucoadhesive time investigated in volunteers (MT) was influenced by AG concentration and was greater than corresponding FT values. Formulations containing 0.3%, w/v AG (F3 and F9) were able to sustain the release (~99%) for both drugs till 3 h. The optimized formulation (F9) did not evoke any inflammation, irritation or pain in the buccal cavity of healthy volunteers and was also stable up to 6 months. Therefore, AG could be considered a natural and potential polymer with profound mucoadhesive properties to deliver drugs through the mucosal route.

Benzocaine is a local anesthetic used in pain control management, and it is in the ester local anesthetic class of medications. This activity describes the indications, action, and contraindications for benzocaine as a valuable agent in managing pain control. This activity will highlight the mechanism of action, adverse event profile, and other key factors (e.g., off-label uses, dosing, pharmacodynamics, pharmacokinetics, monitoring, relevant interactions) pertinent for members of the interprofessional team in the management of patients undergoing procedures requiring local anesthetic and pain control.

The frog sciatic nerve provides a robust physiological preparation students may conveniently use to investigate the properties of compound action potentials. Electrical stimulation with standard physiology teaching equipment elicits compound action potentials that are easily recorded by upper-level undergraduate students. The amplitude of compound action potentials increases with greater stimulation voltages, up until a maximum response is achieved. Plotting action potential size as a function of stimulating voltage produces a curve that illustrates the responsiveness of a nerve. In the present study, several local anesthetics (MS-222, procaine, lidocaine, benzocaine, and tetracaine) were used to reversibly suppress compound action potentials within a time frame consistent with the limitations of teaching labs. Highly responsive nerves generate steep response curves that reach asymptotes at relatively low stimulating voltages. Less active nerves require higher stimulating voltages and appear "right-shifted." Anesthetized response curves may also appear "flatter," exhibiting lower peak amplitude, when compared to fully active nerves. The magnitude of action potential suppression and time course of recovery depended upon the specific anesthetic applied. Nerves anesthetized with MS-222 were the fastest to recover, reaching their original responsiveness within 20 min. Tetracaine had the most dramatic effects, with nerves typically requiring more than a day to fully recover physiological responses. Carefully dissected nerves maintained their physiological responses for many days when stored in Ringer solution at 4°C, making this preparation particularly useful for undergraduate lab experiences. Quantitative analyses may be performed on the data collected, providing students with opportunities to design and implement their own experiments.NEW & NOTEWORTHY The frog sciatic nerve preparation represents a "classical" physiology lab for demonstrating principles of action potentials. Local anesthetics provide an inexpensive tool to manipulate the physiological activity of nerves and other excitable tissues. Isolated nerves retain their physiological activity for up to several days when kept in Ringer solution at 4°C. Quantitative data analysis from this robust nerve preparation should present students with many opportunities for designing their own experiments with anesthetics.

Cocaine is one of the most commonly trafficked and abused drugs in the United States, and deployable field tests are important for rapid identification in nonlaboratory settings. At present, colorimetric tests exist for in-field determination, but these fundamentally suffer from interferent effects. Cocaine is an organic salt that is readily water soluble as a cation and almost insoluble in the deprotonated neutral form. Here, we take advantage of the electrochemical window of water to increase the pH at the electrode surface by driving water reduction, effectively electroprecipitating the cocaine base. The precipitate on the electrode surface is then electrochemically oxidized by a voltammetric sweep through sufficiently positive potentials. We demonstrate excellent selectivity to cocaine compared to common adulterants, such as procaine, lidocaine, benzocaine, caffeine, and levamisole. Finally, we detect cocaine on a carbon fiber microelectrode, demonstrating miniaturizability and allowing access to low-resistance media (e.g., tap water).

We managed to obtain three different series of 2,3-dimethyl-1,4-benzoquinones, named nonhalogenated and halogenated (brominated and chlorinated) PQ analogues, via the molecular hybridization strategy. Sixteen of eighteen hybrid molecules were selected by the National Cancer Institute (NCI) of Bethesda for their in vitro antiproliferative potential against the full NCI 60 cell line panel. The hybrid molecules (BrPQ5, CIPQ1, and CIPQ3) showed good growth inhibition at 10 μM concentration, particularly against breast cancer cell lines. As per the results obtained from in vitro antiproliferative evaluation, cytotoxic activities of the hybrid molecules (BrPQ5, CIPQ1, and CIPQ3) were evaluated with an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in T47D and MCF7 breast cancer and human umbilical vein endothelial (HUVEC) cells. Molecules exhibited cytotoxic activity, and especially, CIPQ1 showed remarkable cytotoxic activity and good selectivity on T47D and MCF7 cells. Furthermore, CIPQ1 could inhibit cell proliferation, cause apoptotic cell death and disturb the cell cycle in T47D and MCF7 cells. Additionally, CIPQ1 caused oxidative stress induction in both cells, more so in T47D. In vitro study results indicated that the anticancer activity of CIPQ1 was more prominent in T47D cells than in MCF7 cells. The compound CIPQ1 showed a prominent binding with JNK3 in silico. Thus, the obtained hybrid molecules via the molecular hybridization strategy of two important pharmacophores could be useful in the discovery of novel antiproliferative agents, and CIPQ1 could be considered a promising drug candidate.

Agarose (AG) forms hydrocolloid in hot water and possesses a noteworthy gel strength. However, no reasonable scientific work on investigating the mucoadhesive character of AG has been reported. Therefore, the current study was designed to develop AG and carbopol (CP) based buccal gel scaffold for simultaneous release of benzocaine (BZN) and tibezonium iodide (TIB). Gels' scaffold formulations (F1-F12) were prepared with varied concentrations (0.5-1.25% w/v) of AG and CP alone or their blends (AG-CP) using homogenization technique. The prepared formulations were characterized for solid-state, physicochemical, in vitro, ex vivo, and in vivo mucoadhesive studies in healthy volunteers. The results showed that mucoadhesive property of AG was concentration dependent but improved by incorporating CP in the scaffolds. The ex vivo mucoadhesive time reached >36 h when AG was used alone or blended with CP at 1% w/v concentration or above. The optimized formulation (F10) depicted >98% drugs release within 8 h and was also storage stable up to six months. The salivary concentration of BZN and TIB from formulation F10 yielded a Cmax value of 9.97 and 8.69 µg/mL at 2 and 6 h (tmax), respectively. In addition, the FTIR, PXRD, and DSC results confirmed the presence of no unwanted interaction among the ingredients. Importantly, the mucoadhesive study performed on healthy volunteers did not provoke any signs of inflammation, pain, or swelling. Clearly, it was found from the results that AG-CP scaffold provided better mucoadhesive properties in comparison to pure AG or CP. Conclusively, the developed AG based mucoadhesive drug delivery system could be considered a potential alternative for delivering drugs through the mucoadhesive buccal route.

Methemoglobinemia is a rare cause of hypoxia and can be a diagnostic challenge early in the disease course. The incidence of medication-induced methemoglobinemia is more common than congenital-related methemoglobinemia. The most common cause of methemoglobinemia is exposure to household detergents, illicit drugs, or medications with nitrate or sulfonamide chemical groups. The 2 main medications accounting for up to 45% of medication-induced cases are dapsone and benzocaine. We report a case of hypoxia and diarrhea with an arterial blood gas (ABG) showing methemoglobinemia at 26%. Infectious and autoimmune workup were negative. Methemoglobinemia level returned to normal level within 2 weeks of hydrochlorothiazide discontinuation, suggesting medication-induced methemoglobinemia at appropriate hypertension dosage. In this case, there was an acute rise in methemoglobin levels following initiation of an hydrochlorothiazide-losartan combination, which improved following the discontinuation of hydrochlorothiazide. Extensive workup ruled out cytochrome b5 reductase (Cb5R) and Glucose-6-phosphate dehydrogenase (G6PD) deficiency, which raised the suspicion of hydrochlorothiazide-induced methemoglobinemia, as it is part of the sulfa drug family.

Allergic diseases are among the most common diseases worldwide. For appropriate management knowledge of the allergy trigger is crucial. The clinical picture of allergic diseases is diverse and correct diagnosis is often a challenge. The allergist needs to distinguish intolerances from allergies and infectious diseases from non-infectious triggers. Test results have to be interpreted accordingly to differentiate sensitizations from allergies. In this review current state of the art diagnostic measures to diagnose type I and type IV allergies are described and discussed.Immediate type allergies such as allergic rhinoconjunctivitis, asthma and anaphylaxis are mediated by allergen-specific IgE antibodies detectable both in serum and tissue. Typical triggers are pollen, mites, animal epithelia, food, insect toxins and pharmaceuticals. In everyday practice, diagnostics are based on three complementary pillars: the allergy-specific anamnesis as a prerequisite of correct interpretation of subsequent diagnostic tests like skin testing and serological immunoglobulin detection. These can be supplemented as required and available by provocation tests to prove clinical reactivity and cellular assays to demonstrate the cellular immune response.Type IV allergic reactions are mediated by T cells causing contact allergy with a local eczematous reaction with a latency of several hours to days. Some 3,500 triggers, often from occupational environment, are known; e. g., nickel, chromium, cobalt, fragrances, rubber, plastics, preservatives, dyes, neomycin, benzocaine, sulfonamides, quinidine, wool wax, perubalsam, eye therapeutics, light filter substances, disinfectants, pesticides, technical oils or plants. Diagnosis of contact allergy combines the history of cutaneous exposure with associated symptoms and patch testing, with detection of a late phase clinical reaction after 6 to 48, up to a maximum of 96 hours after antigen contact.

Coupled with an azo coupling reaction, a simple, rapid, sensitive, and effective surface-enhanced resonance Raman scattering (SERRS) detection method for benzocaine was developed. In our study, benzocaine which is used clinically as a local anesthetic was derived with p-aminothiophenol into a corresponding azo product within 5 min, resulting in a strong SERRS response with the simple addition of Ag NPs excited with a 532 nm laser. The linear correlation between SERRS intensity of dominant bands and logarithm of benzocaine concentration was investigated for quantitative determination. The method reached a limit of detection (LOD) down to 0.139 and 0.0788 μg/mL calculated with two peak intensity ratios (I1568/I2260 and I1331/I2260), which is comparable to most studies reported previously, and meanwhile had superiority in simplicity and rapidness. The quantitative measurements for pharmaceutical preparations with benzocaine were conducted without complex extraction and enrichment processes. It was indicated that the SERRS assay combined with azo derivatization reaction has implications for practical applications in more complicated systems involving biological samples, in which appropriate and simplified pretreatments were conducted to remove interfering components.

UV filters (UVFs) and paraben preservatives (PBs) are widely used components in many personal care products. However, there has been a rising concern for their endocrine-disrupting effects on wildlife once they reach aquatic ecosystems via recreative activities and wastewater treatment plants effluents. This study addresses UVFs and PBs occurrence in seawater and sediment impacted by tourism and sewage discharges along the coast of Mahdia, center East Tunisia. Samples of water and sediment were collected for 6 months from 3 coastal areas. Among the 14 investigated UVFs, 8 were detected in seawater and 4 were found in sediment. All PBs were present in seawater and only methylparaben (MePB) was detected in sediment. Benzophenone-3 (oxybenzone, BP3), benzocaine (EtPABA), and MePB were present in all water samples with concentrations in the ranges 16.4-66.9, 7.3-37.7, and 17.6-222 ng/L, respectively. However, the highest value, 1420 ng/L, corresponded to octinoxate (EHMC). In sediments, avobenzone (AVO), 4-methyl benzylidene camphor (4MBC), EHMC, 5-methyl-1-H-benzotriazole (MeBZT), and MePB were detected at concentrations within the range 1.1-17.6 ng/g dw, being MePB the most frequently detected (89%). MePB and MBZT presented the highest sediment-water partition coefficients and MePB also showed a positive correlation with total suspended solids' water content. Overall, pollutants concentrations remained rather constant along the sampling period, showing little seasonal variation. This study constitutes the first monitoring of UVFs and PBs on the Tunisian coastline and provides occurrence data for reference in further surveys in the country.

Methaemoglobinaemia is defined as elevated methaemoglobin in the blood which is characterised by conversion of some of the reduced ferrous iron elements [Fe2+] to the oxidised ferric [Fe3+] form which does not have capacity to bind and transport oxygen resulting in functional anaemia. Causes can be genetic mutations or acquired by medications such as dapsone, nitrates or benzocaine. Benzocaine is currently being used as a topical anaesthetic agent before certain procedures. We report a case of benzocaine spray-induced methaemoglobinaemia in a patient who underwent oesophagogastroduodenoscopy for evaluation of upper gastrointestinal bleeding.

Decapod crustaceans (crabs, hermit crabs, lobsters, crayfish, shrimps, prawns) are sentient beings, not only responding to noxious stimuli but also being capable of feeling pain, discomfort, and distress. General anaesthesia aims at producing analgesia, immobilization, and unconsciousness, while sedation reduces consciousness, stress, and anxiety, though without analgesia. Anaesthesia is recommended to ensure animal welfare and suppress nociception, pain, and suffering in painful and distressing practice that impairs decapods' welfare. These include long term restrain, surgical procedures, pain control, examination, diagnostic, sampling, treatment, transportation, and euthanasia. The necessary anaesthetic depth, from sedation to surgical anaesthesia, depends on the procedure type. Anaesthetic bath and injection are commonly used, besides inhalation, local anaesthesia, and intracardiac injection. Agents used for the anaesthetic bath include eugenol, isoeugenol, lidocaine, halothane, and essential oils of lemon balm, lemongrass, lemon verbena, and sandalwood. While alphaxalone, eugenol, ketamine-xylazine, lidocaine, morphine, procaine, tiletamine-zolazepam, and xylazine can be used as injectable agents administered on the arthrodial membrane or intramuscular injection. Halothane can be used on inhalation anaesthesia. Local anaesthetics include lidocaine and benzocaine. Notwithstanding, many others are detrimental or ineffective to decapods, thus discouraged. They include but not limited to hypothermia, carbon dioxide, chlorpromazine, chloroform, ethanol, ether, magnesium salts, tricaine methanesulfonate (MS-222), mint and lavender essential oils, passionflower extract, and valerian. Decapods' welfare, protection, and veterinary attention should not be neglected, but they must receive ethical treatment, including the best of our knowledge and available tools to ensure they are free of pain and discomfort whenever we deal with them.

Background Lichen planus (LP) is a pathology that affects the skin and the mucosa. The lips are rarely involved but represent a diagnostic challenge in those cases. Oral lichenoid lesions (OLL) are defined as lesions that resemble oral lichen planus (OLP) but do not fully meet the clinical and/or histologic criteria for OLP. This study aimed to present our case series and to study the correlation between the location of the lesion and the dental factor (resin composite, amalgams, crowns, abrasive teeth, and mandibular crossbite) that could cause the lesion. Methods We conducted a retrospective observational study of 23 patients with LP/OLL of the lips treated in the Department of Oral Mucosal Pathology of the Department of Stomatology and Maxillofacial Surgery of the Pitié-Salpêtrière Hospital in Paris between January 2017 and February 2021. We noted the location of the lesion (upper, lower, or both lips), medical history, treatments, smoking habits, and the aspect of the teeth facing the lesion. Patients received a local corticoid treatment and were monitored via follow-up. Results Sixteen patients had lesions on the upper lip, two on the lower lip, and five on both lips, and most patients (n = 14, 60.1%) had a dental factor facing the lesion (e.g., abrasive teeth, resin composites, dental crowns, and mandibular crossbite). Six patients received clobetasol propionate, and 15 patients received a preparation combining betamethasone and benzocaine (Orabase, ConvaTec, Deeside, UK). Fourteen patients returned for post-treatment follow-up consultations approximately two months after treatment. Seven patients saw clinical improvement, five had partial improvement, and two had no improvement. Conclusions Lesions of the labial mucosa appear to be a rare condition in LP/OLL. The difference between LP and OLL can be difficult, even with histological analysis. Its pathogenesis remains unknown, although some studies found evidence of lichenoid reactions of the lips in contact with dental composite restorations. In our study, 14 of our patients had a dental factor facing the lesions. However, our study failed to show a correlation between the presence of an inducing factor and the lesion. In a future study, the potential effect of dental inducing factor removal could be studied. This topic requires further investigations, particularly regarding the inducing factor and the optimal therapeutic approach.

Euthanasia in zebrafish (Danio rerio) younger than 5 days post fertilization (dpf) is poorly described in the literature, and standardized protocols are lacking, most likely because larvae not capable of independent feeding are often not protected under national legislations. We assessed the euthanasia efficacy in laboratories in different countries of a one hour anesthetic overdose immersion with buffered lidocaine hydrochloride (1 g/L, with or without 50 mL/L of ethanol), buffered tricaine (1 g/L), clove oil (0.1%), benzocaine (1 g/L), or 2-phenoxyethanol (3 mL/L), as well as the efficacy of hypothermic shock (one hour immersion) and electrical stunning (for one minute), on zebrafish at <12 h post fertilization (hpf), 24 hpf, and 4 dpf. Based on the survival/recovery rates 24 h after treatment, the most effective methods were clove oil, lidocaine with ethanol, and electrical stunning. For 4 dpf larvae, signs of aversion during treatment demonstrated that all anesthetics, except lidocaine, induced aversive behavior. Therefore, the most suited euthanasic treatment was lidocaine hydrochloride 1 g/L, buffered with 2 g/L of sodium bicarbonate and mixed with 50 mL/L of ethanol, which euthanized both embryos and larvae in an efficient and stress-free manner. Electrical stunning also euthanized embryos and larvae efficiently and without signs of aversion; this method needs further assessment in other laboratories to draw firm conclusions.

Topical delivery of local anesthetics (LAs) is commonly used to decrease painful sensations, block pain throughout procedures, and alleviate pain after surgery. Dermal and/or transdermal delivery of LAs has other advantages, such as sustained drug delivery and decreased systemic adverse effects. This study reports the development of poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles coated with chitosan for the sustained release and topicality of benzocaine (BZC) and topical delivery. BZC PLGA nanoparticles or nonencapsulated drugs were further incorporated into Poloxamer hydrogels (Pluronic™ F-127). The nanoparticles showed a mean diameter of 380 ± 4 nm, positive zeta potential after coating with chitosan (23.3 ± 1.7 mV), and high encapsulation efficiency (96.7 ± 0.02%). Cellular viability greater than 70% for both fibroblasts and keratinocytes was observed after treatment with nanoparticles, which is in accordance with the preconized guidelines for biomedical devices and delivery systems. Both the nanoparticles and hydrogels were able to modulate BZC delivery and increase drug permeation when compared to the nonencapsulated drug. Furthermore, the incorporation of limonene into hydrogels containing BZC-loaded nanoparticles increased the BZC permeation rates. Non-Newtonian and pseudoplastic behaviors were observed for all hydrogel nanoformulations with or without nanoparticles. These results demonstrate that the hydrogel-nanoparticle hybrids could be a promising delivery system for prolonged local anesthetic therapy.

The use of drugs of abuse has grown significantly in recent decades. In forensic chemistry, methods of identifying and characterizing illicit drugs contribute to the interests of researchers, experts, and public security authorities. Among existing methods, portable Raman spectroscopy is notable for performing rapid, non-destructive, and highly selective analysis in the laboratory or on-site. When the resulting spectral data are paired with chemometric tools, methods of exploratory analysis and multivariate calibration can be developed. Thus, this work describes the application of Raman spectroscopy associated with principal component analysis (PCA) and interval principal component analysis (iPCA) to assessing trends in samples of cocaine (n = 40), crack (n = 33), and their main adulterants (n = 5) and diluents (n = 5), tablets of ecstasy (n = 14), designer drugs papers (n = 27), and alcoholic solutions adulterated with benzodiazepines (alprazolam and diazepam). In addition, competitive adaptive reweighted sampling (CARS) combined with partial least squares (PLS) regression (CARSPLS) was used to quantify adulterants (benzocaine, lidocaine, and procaine) in binary mixtures with crack (n = 21) and solutions of cachaça adulterated with bromazepam (n = 11).

Methaemoglobinaemia is a potentially life-threatening condition characterised by hypoxaemia, cyanosis, pallor, fatigue, metabolic acidosis, headache and in severe cases, coma or death. Topical anaesthetics have been reported to cause methaemoglobinaemia. Topical benzocaine was specifically implicated in roughly 66% of anesthetic-induced methaemoglobinaemia cases in a large systematic review in adults. This complication has occurred often in adult patients with pre-existing comorbidities resulting in diminished use in children overall with only few paediatric cases reported worldwide. Additionally, there is growing evidence of a link between sepsis and methaemoglobinaemia due to increased circulating nitrous oxide from infectious pathogen metabolism. In this report, we discuss a case of a 16-year-old young boy, being evaluated for suspected endocarditis, presenting with acute methaemoglobinaemia after use of topical benzocaine spray for transesophageal echocardiogram. This case exemplifies the importance of blood gas with co-oximetry testing in all cases of refractory hypoxemia who have had procedures requiring topical anaesthetics.

The protonation site of molecules can be varied by their surrounding environment. Gas-phase studies, including the popular techniques of infrared spectroscopy and ion mobility spectrometry, are a powerful tool for the determination of protonation sites in solvated clusters but often suffer from inherent limits for larger hydrated clusters. Here, we present collision-assisted stripping infrared (CAS-IR) spectroscopy as a new technique to overcome these problems and apply it in a proof-of-principle experiment to hydrated clusters of protonated benzocaine (H+BC), which shows protonation-site switching depending on the degree of hydration. The most stable protomer of H+BC in the gas phase (O-protonated) is interconverted into its most stable protomer in aqueous solution (N-protonated) upon hydration with three water molecules. CAS-IR spectroscopy enables us to unambiguously assign protonation sites and quantitatively determine the relative abundance of various protomers.

Benzocaine (BZC) is a local anaesthetic drug coupled with numerous adverse effects, and thus poses a great challenge for its simple and highly sensitive detection. For resolving this issue, hydroxypropyl-β-cyclodextrin-carbon black (HP-β-CD-CB) nanohybrid that possesses the collaborative advantages of CB (e.g., excellent electrical properties, large surface area) and HP-β-CD (e.g., high molecule recognition and preconcentration capability) was synthesized in this study via a simple process and then utilized as a novel electrode material to electrochemically detect BZC. With the optimized experimental conditions, the HP-β-CD-CB nanohybrid-modified electrode shows wide linearity from 0.05 to 7.0 μM and very low detection limit (0.015 μM) for BZC detection. In addition, the repeatability, stability, and selectivity as well as practical-sample analysis of the HP-β-CD-CB electrode were investigated, and the observed results are desirable. The superior sensing performances coupled with its advantages including low-cost, simple and highly sensitive detection suggest that HP-β-CD-CB has important potential application for BZC analysis in practical samples.

To evaluate the impact of photobiomodulation therapy (PBMT) on injection pain perception and compare it with a topical oral anesthetic gel. A total of 30 patients of 6 to 9 years-old seeking pulpotomy treatment of maxillary secondary primary molars of both sides were considered for this split-mouth triple-blind randomized clinical trial. On one side of the maxilla, the low-level laser (diode laser, 808 nm, 250 mW; 16.25 J; 32.5 J cm-2) was irradiated upon the buccal gingiva of the tooth, while a Benzocaine 20% topical anesthetic gel was applied on the other side. A gel with the same taste (strawberry) was applied for the placebo. The Wong-Baker Faces Pain Rating Scale was used to evaluate the injection pain and postoperation pain at two timestamps, 1 h and 24 h after treatment. Patients' heart rate was also evaluated. Paired t, Wilcoxon signed-rank test, McNemar and Friedman tests were used for statistical analyses. Results demonstrated that PBMT could significantly decrease the injection pain perception and heart rate alternations compared to the topical anesthetic gels (P = 0.000). However, no significant differences were documented between the two methods concerning the 1-h (P = 0.26) and 24-h (P = 1.00) postoperation pain. PBMT can be an effective nonpharmacological technique for controlling injection pain.

The need for new chemotherapeutics to overcome development of resistance merits research to discover new agents. Benzocaine derivatives are essential compounds in medicinal chemistry due to their various biological activities including antibacterial and anticancer activities. Therefore, this study focuses on the synthesis of new benzocaine derivatives 3a-e, 6, 7a and 7b, 8, 10-14, and 16a-d and their in vitro evaluation as antibacterial agents against gram +ve and -ve strains and as anticancer agents against HepG-2, HCT-116, and MCF-7 human cancer cell lines. The obtained results demonstrated that thiazolidines 6 and 7b showed higher antibacterial and anticancer activity in comparison with the reference drugs. In addition, 6 and 7b showed high potency as inhibitors toward their biological targets, that is DNA gyrase and human topoisomerase IIα, as compared to the reference standard drugs novobiocin and etoposide, respectively. Molecular docking demonstrated that both compounds could identify the active site of their target enzymes and develop effective binding interactions. Absorption, distribution, metabolism and elimination (ADME) and drug-likeness predictions of both compounds showed that they both have good ADME profiles and no structural alerts that might cause toxicity. Based on this, 6 and 7b could serve as lead compounds for the design of more potent antibacterial and anticancer agents.