Structural modeling of Nav1.5 pore domain in closed state

The voltage-dependent cardiac sodium channel plays a key role in cardiac excitability and conduction and it is the drug target of medically important. However, its atomic- resolution structure is still lack. Here, we report a modeled structure of Na_v1.5 pore domain in closed state. The structure was constructed by Rosetta-membrane homology modeling method based on the template of eukaryotic Na_v channel Na_vPaS and selected by energy and direct coupling analysis (DCA). Moreover, this structure was optimized through molecular dynamical simulation in the lipid membrane bilayer. Finally, to validate the constructed model, the binding energy and binding sites of closed-state local anesthetics (LAs) in the modeled structure were computed by the MM-GBSA method and the results are in agreement with experiments. The modeled structure of Na_v1.5 pore domain in closed state may be useful to explore molecular mechanism of a state-dependent drug binding and helpful for new drug development.

Anaphylactic reactions to local anesthetics in dental practice: a nationwide French retrospective study

OBJECTIVES

The primary aims of the present study were (1) to quantify and characterize anaphylactic type I reactions related to local anesthetics (LAs) drawing on the French Pharmacovigilance Database System over a 35-year period and (2) to focuse on reactions associated with dental procedures. The secondary aim was to infer an incidence rate in dental practice.

MATERIALS AND METHODS

All cases of anaphylactic reactions were selected using the algorithmic Standardized MeDRA Query "anaphylactic reaction." For each reaction, comprehensive data were collected, in particular the severity of symptoms, risk factors for anaphylaxis, and allergy testing. Imputability was assessed and a crude incidence rate in dental practice was estimated.

RESULTS

The first-line search identified 416 anaphylactic reactions, mostly of grade II (138) or III (240) severity. When restricted to dental practice, this number fell to 26 (grade I: 4; grade II: 10; grade III: 11; and grade IV: 1). Lidocaine was most often involved (81.49%) and mostly associated with anaphylactic reactions of grade II and III. Overall, 11 cases of fatal anaphylaxis were recorded, but no in dental practice. In dental practice, lidocaine was also the most frequently involved LA (57.69%).

CONCLUSIONS

All these findings highlight the very low incidence of type I-IgE-mediated reactions to LA, particularly in dental practice. The incidence rate of LA anaphylctic episodes in dental practice was estimated as 0.0261 anaphylactic episodes per million LA cartridges.

CLINICAL RELEVANCE

True anaphylactic reactions to LAs do occur and may justify a thorough investigation in dental practice.

Prolonged anesthesia and decreased toxicity of enantiomeric-excess bupivacaine loaded in ionic gradient liposomes

Bupivacaine is the most employed local anesthetic in surgical procedures, worldwide. Its systemic toxicity has directed the synthesis of the less toxic, S(-) enantiomer. This work describes a formulation of ionic gradient liposomes (IGL) containing _S75BVC, an enantiomeric excess mixture of 75% S(-) and 25% R(+) bupivacaine. IGL prepared with 250 mM (NH₄)₂SO₄ in the inner aqueous core of phosphatidylcholine and cholesterol (3:2 mol%) vesicles plus 0.5% _S75BVC showed average sizes of 312.5 ± 4.5 nm, low polydispersity (PDI < 0.18), negative zeta potentials (-14.2 ± 0.2 mV) and were stable for 360 days. The encapsulation efficiency achieved with IGL_S75BVC (%EE = 38.6%) was higher than with IGL prepared with racemic bupivacaine (IGL_RBVC, %EE = 28.3%). TEM images revealed spherical vesicles and µDSC analysis provided evidence on the interaction of the anesthetic with the lipid bilayer. Then, in vitro - release kinetics and cytotoxicity- and in vivo - toxic effects in Zebrafish and biochemical/histopathological analysis plus analgesia in Wistar rats - tests were performed. IGL_S75BVC exhibited negligible toxicity against Schwann cells and Zebrafish larvae, and it did not affect biochemical markers or the morphology of rat tissues (heart, brain, cerebellum, sciatic nerve). The in vitro release of _S75BVC from IGL was extended from 4 to 24 h, justifying the prolonged anesthetic effect measured in rats (~9 h). The advantages of IGL_S75BVC formulation over IGL_RBVC and plain bupivacaine formulations (prolonged anesthesia, preferential sensorial blockade, and no toxicity) confirm its potential for clinical use in surgical anesthesia.

Transversus Abdominis Plane Block Versus Intraperitoneal Local Anesthetics in Bariatric Surgery: A Systematic Review and Network Meta-analysis

BACKGROUND

Transversus abdominis plane (TAP) block and intraperitoneal local anesthetics (IPLA) are widely investigated techniques that potentially improve analgesia after bariatric surgery. The analgesic efficacy of TAP block has been shown in previous studies, but the performance of TAP block can be difficult in patients with obesity. We performed a systematic review and meta-analysis to compare the analgesic efficacy of TAP block and IPLA. An alternative technique is useful in clinical setting when TAP block is not feasible.

METHODS

We searched PubMed, Embase, and CENTRAL from inception until August 2020 for randomized controlled trials comparing both techniques. The primary outcome was cumulative morphine consumption at 24 h. Secondary pain-related outcomes included pain score at rest and on movement at 2, 6, 12, and 24 h; postoperative nausea and vomiting; and length of hospital stay.

RESULTS

We included 23 studies with a total of 2,178 patients. TAP block is superior to control in reducing opioid consumption at 24 h, improving pain scores at all the time points and postoperative nausea and vomiting. The cumulative opioid consumption at 24 h for IPLA is less than control, while the indirect comparison between IPLA with PSI and control showed a significant reduction in pain scores at rest, at 2 h, and on movement at 12 h, and 24 h postoperatively.

CONCLUSIONS

Transversus abdominis plane block is effective for reducing pain intensity and has superior opioid-sparing effect compared to control. Current evidence is insufficient to show an equivalent analgesic benefit of IPLA to TAP block.

Herpes Labialis: A New Possibility for Topical Treatment with Well-Elucidated Drugs

Mucocutaneous infections caused by Herpes simplex virus (HSV-1 and HSV-2) are characterized by the appearance of vesicles that cause pain and embarrassment to the carrier. The standard treatment is based on the use of antivirals in gels or ointments, however, relapses are common. Local anesthetics decrease the pain caused by the lesion, in addition to showing antiviral properties. Semi-solid form facilitates application and its transformation into a thin film favors the maintenance of the formulation in place, with a more discreet final aspect. The objective of this study was to develop and evaluate formulations containing anesthetics for the treatment of cold sores. For this purpose, two semi-solid film-forming formulations were developed and evaluated, containing HPMC K100, lidocaine (LIDO) and prilocaine (PRILO) combined with adjuvants, in the presence (F1T) or not (F1) of the absorption promoter Transcutol®. The mixture of PRILO and LIDO resulted in the formation of a eutectic mixture (EM), essential for penetration of drugs into the skin. The quantification of drugs was performed by HPLC (High Performance Liquid Chromatography), and Transcutol® did not influence the release of drugs from the formulation. The bioadhesiveness of the formulation was evaluate and the drugs did not impair the adhesive potential of the polymers used. The formulations were evaluated in vivo for skin irritation and did not show any negative sign on macroscopic examination. The in vivo efficacy test proved the anesthetics' ability to decrease the lesions caused by HSV-1. Thus, the proposed formulations proved to be good alternatives to the treatment of oral lesions caused by HSV-1.

Trigone as a diagnostic and therapeutic target for bladder-centric interstitial cystitis/bladder pain syndrome

The pathophysiology of interstitial cystitis/bladder pain syndrome (IC/BPS) may be bladder-centric, with afferent nerve hyperexcitability and/or due to neural central sensitization. In bladder-centric disease, the trigone's unmyelinated nociceptive C-fibers are thought to be upregulated, suggesting this as a potential target for diagnostic modalities and for treatment with local anesthetics and chemodenervation. We propose that the transvaginal trigone treatment (T3) route of administration of such treatments should be considered in women with IC/BPS, as this approach is easier and less invasive than cystoscopy. For T3, or other bladder-centric treatments to be successful, patient selection should attempt to exclude patients with predominantly neural central sensitization.

Comparing Articaine brands: A randomized non-inferiority controlled trial

Introduction

The substitution of reference drugs for similar, new or existing drugs in the market is a dilemma present in daily dental procedures. In order to decide whether or not to adopt a new drug in relation to the reference, a clinical trial can provide the necessary evidence.

Methods

A total of 179 healthy volunteers (18-25 years) requiring extraction of mandibular third molars completed the study. Subjects were randomized into 4 groups: right, left, Arteek-SP and Septanest. Allocations consisted of 4% Articaine hydrochloride with 1:10000 epinephrine. The primary aim of this randomized controlled trial was to determine whether the test drug Arteek-SP was noninferior by a margin of 10% in the proportion of patients with total absence of pain, compared to the reference drug Septanest in the extraction of mandibular third molars using inferior alveolar nerve blocks. Secondary outcomes included, hemodynamic parameters, volume (mL), pain scores assessed during one visit and reported postoperative discomfort assessed during 8 days. Noninferiority was declared if total absence of pain for both groups was equal to 0.9, with a significance level of 5% (P < 0.05) and power at 90% (β = 0.1) at 95% confidence level.

Results

Arteek-SP was applied during the first surgery to 90 volunteers (50.28%) and Septanest was applied to 89 subjects (49.72%). Less than 10% difference was identified, in the proportion of patients with total absence of tooth pain P < 0.05 and in the gum P < 0.1, at 95% CI, when Arteek-SP was applied first in comparison with Septanest, establishing noninferiority.

Conclusion

The clinical performance of the test drug Arteek-SP is noninferior to the reference drug Septanest. They can be considered interchangeable in terms of cost or convenience.

Registration

ClinicalTrials.org, number NCT4166890.

Lipid nanocapsules loaded with prilocaine and lidocaine and incorporated in gel for topical application

Lipid nanocapsules (LNC) are special drug delivery system (DDS) carriers obtained by the phase-inversion temperature method (PIT). This study describes the encapsulation of the local anesthetics (LA) prilocaine (PLC) and lidocaine (LDC) in lipid nanocapsules (LNC_PLC+LDC) optimized by 2³ factorial design, characterized through DLS, NTA, CRYO-EM and release kinetics and incorporated in carbopol gel (Gel_{LNC PLC+LDC}) prior to in vivo anesthetic effect (in mice) evaluation. A very homogeneous population of small (50 nm; polydispersity index = 0.05) spherical nanocapsules with negative zeta potentials (-21 mV) and ca. 2.3 × 10¹⁵ particles/mL was obtained. The encapsulation efficiency was high (81% and 89% for prilocaine and lidocaine, respectively). The release rate profile was free PLC = free LDC > LNC_PLC+LDC > Gel_{LNC PLC+LDC}. The hybrid system increased (4x) the anesthesia time in comparison to an equipotent gel formulation prepared without LNC. No tissue damage was detected on the tail skin of mice that received the formulations. This study shows that lipid nanocapsules are suitable carriers for PLC and LDC, promoting longer and safer topical anesthesia. Gel_{LNC PLC+LDC} is mucoadhesive and suitable for application in the mouth, where it could be used as a pre-anesthetic, to reduce pain of needle stick (infiltrative anesthesia).

Perturbation of Ca2+ stores and store-operated Ca2+ influx by lidocaine in neuronal N2A and NG108-15 cells

In this report we examined the effects of lidocaine on Ca²⁺ homeostasis of neuronal cells using microfluorimetric measurement of cytosolic Ca²⁺ with fura 2 as probe. In mouse neuroblastoma N2A cells, 10 mM lidocaine caused Ca²⁺ release from the cyclopiazonic acid (CPA)-dischargeable pool and abolished ATP-triggered Ca²⁺ release. Lidocaine-triggered Ca²⁺ release was not affected by xestospongin C (XeC), an inositol 1,4,5-trisphosphate receptor (IP3R) inhibitor. N2A cells did not have functional ryanodine receptors (RYR) (absence of caffeine response) and we used differentiated NG108-15 cells (presence of caffeine response) for further experiments. Caffeine-triggered Ca²⁺ release was unaffected by a brief lidocaine exposure, but was eliminated after a prolonged treatment of lidocaine, suggesting lidocaine abolished caffeine action possibly not by interfering caffeine binding but via Ca²⁺ store depletion. Lidocaine-elicited Ca²⁺ release was unaffected by XeC or a high concentration of ryanodine, suggesting Ca²⁺ release was not via IP3R or RYR. Lidocaine did not affect nigericin-dischargeable lysosomal Ca²⁺ stores. Lastly, we observed that lidocaine suppressed CPA-induced store-operated Ca²⁺ influx in both N2A cells and differentiated NG108-15 cells. Our results suggest two novel actions of lidocaine in neuronal cells, namely, depletion of Ca²⁺ store (via an IP3R- and RYR-independent manner) and suppression of store-operated Ca²⁺ influx.

Local Anesthetic Usage Among Dentists: German and International Data

The aim of this study was to analyze the use of dental local anesthetics in Germany compared with international data. The type and distribution of dental local anesthetics and added vasoconstrictors based on a representative sample of German dentists itemized over a period of 7 years (2011 to 2017) were evaluated and statistically analyzed. The results were compared with international dental local anesthetic consumption data published since 2005. With a consistent market share of nearly 98%, articaine was the first-line local dental anesthetic agent in Germany. During the investigation period, German dental local anesthetics with epinephrine 1:200,000 had ∼50% market shares, whereas formulations with epinephrine 1:100,000 had 40% to 45% market shares. Articaine, with market shares between 38% and 81%, was also the preferred anesthetic agent in various other countries, with the notable exceptions of the United Kingdom and the United States, where lidocaine was the preferred local anesthetic agent. Epinephrine was the preferred vasoconstrictor internationally, similar to Germany. The larger market share of higher concentrated epinephrine 1:100,000 was remarkable, considering the increasing number of medically compromised patients. Increased consideration for using agents with reduced dosages of epinephrine (1:200,000) is generally recommended.

Treatment of Localized Vulvar Pain with Neural Therapy: A Case Series and Literature Review

BACKGROUND

Localized vulvar pain (LVP) is a common condition among fertile women, with physical and psychosexual implications. Treatment is complex with limited benefits. Neural therapy is a regulatory therapy that uses injections of local anesthetics in low concentrations in specific points to treat different conditions.

CASE PRESENTATION

We present the cases of 5 women, ages 33-44 years, with LVP treated with procaine 0.5% injections in painful points. Complete relief from pain occurred in 2 patients, and significant improvement in 3. Only 1 or 2 sessions were required. Initial VAS score was ≥70 and decreased to ≤30 after the intervention. The improvement was maintained over time, with a minimum follow-up period of 6 months. None of the patients were able to have sex or use tampons due to pain, but they were able to resume after the intervention.

CONCLUSIONS

In this case series, local injections of procaine showed a favorable outcome. Future randomized clinical trials could help elucidate the role of this intervention in LVP.

Topical anesthetic and pain relief using penetration enhancer and transcriptional transactivator peptide multi-decorated nanostructured lipid carriers

Many strategies have been developed to overcome the stratum corneum (SC) barrier, including functionalized nanostructures. Chemical penetration enhancers (CPEs) and cell-penetrating peptides (CPP) were applied to decorate nanostructured lipid carriers (NLC) for topical anesthetic and pain relief. A novel pyrenebutyrate (PB-PEG-DSPE) compound was synthesized by the amide action of the carboxylic acid group of PB with the amido groups of DSPE-PEG. PB-PEG-DSPE has a hydrophobic group, hydrophilic group, and lipid group. The lipid group can be inserted into NLC to form PB functional NLC. In order to improve the penetrability, TAT and PB multi-decorated NLC were designed for the delivery of lidocaine hydrochloride (LID) (TAT/PB LID NLC). The therapeutic effects of NLC in terms of in vitro skin penetration and in vivo in animal models were further studied. The size of TAT/PB LID NLC tested by DLS was 153.6 ± 4.3 nm. However, the size of undecorated LID NLC was 115.3 ± 3.6 nm. The PDI values of NLC vary from 0.13 ± 0.01 to 0.16 ± 0.03. Zeta potentials of NLC were negative, between -20.7 and -29.3 mV. TAT/PB LID NLC (851.2 ± 25.3 µg/cm²) showed remarkably better percutaneous penetration ability than PB LID NLC (610.7 ± 22.1 µg/cm²), TAT LID NLC (551.9 ± 21.8 µg/cm²) (p < .05) and non-modified LID NLC (428.2 ± 21.4 µg/cm²). TAT/PB LID NLC exhibited the most prominent anesthetic effect than single ligand decorated or undecorated LID NLC in vivo. The resulting TAT/PB LID NLC exhibited good skin penetration and anesthetic efficiency, which could be applied as a promising anesthesia system.

Local anesthetics impair the growth and self-renewal of glioblastoma stem cells by inhibiting ZDHHC15-mediated GP130 palmitoylation

BACKGROUND

A large number of preclinical studies have shown that local anesthetics have a direct inhibitory effect on tumor biological activities, including cell survival, proliferation, migration, and invasion. There are few studies on the role of local anesthetics in cancer stem cells. This study aimed to determine the possible role of local anesthetics in glioblastoma stem cell (GSC) self-renewal and the underlying molecular mechanisms.

METHODS

The effects of local anesthetics in GSCs were investigated through in vitro and in vivo assays (i.e., Cell Counting Kit 8, spheroidal formation assay, double immunofluorescence, western blot, and xenograft model). The acyl-biotin exchange method (ABE) assay was identified proteins that are S-acylated by zinc finger Asp-His-His-Cys-type palmitoyltransferase 15 (ZDHHC15). Western blot, co-immunoprecipitation, and liquid chromatograph mass spectrometer-mass spectrometry assays were used to explore the mechanisms of ZDHHC15 in effects of local anesthetics in GSCs.

RESULTS

In this study, we identified a novel mechanism through which local anesthetics can damage the malignant phenotype of glioma. We found that local anesthetics prilocaine, lidocaine, procaine, and ropivacaine can impair the survival and self-renewal of GSCs, especially the classic glioblastoma subtype. These findings suggest that local anesthetics may weaken ZDHHC15 transcripts and decrease GP130 palmitoylation levels and membrane localization, thus inhibiting the activation of IL-6/STAT3 signaling.

CONCLUSIONS

In conclusion, our work emphasizes that ZDHHC15 is a candidate therapeutic target, and local anesthetics are potential therapeutic options for glioblastoma.

Downregulation of microRNA-199a-5p alleviated lidocaine-induced sensory dysfunction and spinal cord myelin lesions in a rat model

Lidocaine induces neurotoxicity in the spinal cord, but the underlying mechanisms remain unclear. In this study, we evaluated the effects of miR-199a-5p on 10 % lidocaine neurotoxicity. Increased expression of miR-199a-5p in the spinal cord of rats treated with 10 % lidocaine was assessed by qRT-PCR. Furthermore, after miR-199a-5p antagomir administration, the sensory dysfunction and myelin sheath lesions (evaluated by semithin sections stained with toluidine blue, electron microscopy, g-ratios and myelin thickness) induced by 10 % lidocaine were alleviated. Myelin regulatory factor (MYRF), a key molecule of myelin sheath development, was predicted to be a target gene of miR-199a-5p by the TargetScan and miRBase databases. MYRF and its downstream factors myelin basic protein (MBP), proteolipid protein (PLP) and myelin oligodendrocyte glycoprotein (MOG) were significantly decreased after intrathecal 10 % lidocaine administration. Moreover, these changes were reversed after miR-199a-5p antagomir administration. FISH-immunofluorescence showed coexpression of miR-199a-5p and MYRF in the spinal cord white matter of rats. A luciferase reporter assay further demonstrated the functional association between miR-199a-5p and MYRF. Overall, miR-199a-5p upregulation is involved in 10 % lidocaine-induced spinal cord toxicity through regulation of MYRF. Therefore, downregulating miR-199a-5p expression may be a potential strategy to ameliorate spinal cord neurotoxicity induced by 10 % lidocaine.

[Intranasal lidocaine atomization as novel and noninvasive treatment option for postdural puncture headache : Two case reports from obstetric anesthesiology]

Hintergrund

Der Postpunktionskopfschmerz („postdural puncture headache“ [PDPH]) stellt eine ernsthafte anästhesiologische Komplikation geburtshilflich behandelter Patientinnen dar. Führen konservativ-medikamentöse Therapieversuche nicht zu einer Symptomlinderung, empfehlen aktuelle Leitlinien die frühzeitige Durchführung eines epiduralen Blut-Patch. Als potenzielle Alternative wird die transnasale Blockade des Ganglion sphenopalatinum mittels Lokalanästhetika diskutiert.

Methode

In dieser Falldarstellung wird erstmals von einer Modifikation dieser Technik unter Anwendung eines Medikamentenzerstäubers („mucosal atomization device“ [MAD]) zur Therapie eines PDPH bei zwei geburtshilflichen Patientinnen berichtet. Über dieses Verfahren existieren bislang keine Erfahrungen aus der geburtshilflichen Anästhesiologie.

Ergebnisse

Die erste Patientin (25-jährige Zweitgravida, BMI 54,7 kg/m²) zeigte am ersten Tag nach Sectio caesarea in Spinalanästhesie einen ausgeprägten PDPH mit starker Übelkeit und Erbrechen. Bei der zweiten Patientin (32-jährige Drittgravida, BMI 27,3 kg/m²) kam es 4 Tage nach Spontanpartus unter Periduralanästhesie zu einer PDPH-bedingten Wiederaufnahme. Während konservative Maßnahmen sowie Therapieversuche mit Nichtopioidanalgetika und Koffein keinen hinreichenden Behandlungserfolg erzielten, führte die intranasale Lidocainapplikation mittels MAD zu einer unmittelbaren und persistierenden Linderung der Beschwerden. Von beiden Patientinnen wurde die Lidocaingabe sehr gut vertragen; sie konnten am Folgetag aus dem Krankenhaus entlassen werden.

Schlussfolgerung

Die vorgestellte nichtinvasive und einfach durchzuführende Maßnahme stellt eine wertvolle Ergänzung bisheriger Therapieoptionen und eine potenzielle Alternative zum epiduralen Blutpatch bei geburtshilflichen Patientinnen mit PDPH dar.

[Autophagy activation attenuates the neurotoxicity of local anaesthetics by decreasing caspase-3 activity in rats]

BACKGROUND AND OBJECTIVES

The mechanisms by which local anaesthetics cause neurotoxicity are very complicated. Apoptosis and autophagy are highly coordinated mechanisms that maintain cellular homeostasis against stress. Studies have shown that autophagy activation serves as a protective mechanism in vitro. However, whether it also plays the same role in vivo is unclear. The aim of this study was to explore the role of autophagy in local anaesthetic-induced neurotoxicity and to elucidate the mechanism of neurotoxicity in an intrathecally injected rat model.

METHODS

Eighteen healthy adult male Sprague-Dawley rats were randomly divided into three groups. Before receiving an intrathecal injection of 1% bupivacaine, each rat received an intraperitoneal injection of vehicle or rapamycin (1 mg.kg^-1) once a day for 3 days. The pathological changes were examined by Haematoxylin and Eosin (HE) staining. Apoptosis was analysed by TdT-mediated dUTP Nick-End Labelling (TUNEL) staining. Caspase-3, Beclin1 and LC3 expression was examined by Immunohistochemical (IHC) staining. Beclin1 and LC3 expression and the LC3-II/LC3-I ratio were detected by western blot analysis.

RESULTS

After bupivacaine was injected intrathecally, pathological damage occurred in spinal cord neurons, and the levels of apoptosis and caspase-3 increased. Enhancement of autophagy with rapamycin markedly alleviated the pathological changes and decreased the levels of apoptosis and caspase-3 while increasing the expression of LC3 and Beclin1 and the ratio of LC3-II to LC3-I.

CONCLUSIONS

Enhancement of autophagy decreases caspase-3-dependent apoptosis and improves neuronal survival in vivo. Activation of autophagy may be a potential therapeutic strategy for local anaesthetic-induced neurotoxicity.

A controlled release bupivacaine-alginate construct: Effect on chondrocyte hypertrophy conversion

Objective:

Osteoarthritis is a degenerative disease of the joint, affecting over 30 million people in the US¹. A key characteristic of OA is chondrocyte hypertrophy, characterized by chondrocyte changes to a more rounded and osteoblastic phenotype, characterized by increased IL-6 and IL-8 secretion². While there are no cures for OA, treatments focus on mitigating pain and inflammation, the two main symptoms of OA. However, the analgesics, NSAIDS and corticosteroids commonly used, do not target regeneration and have negative side effects. Local anesthetics (LA) can be used as a pain management alternative but are usually short lasting and therefore, not suited for chronic conditions such as OA. Our engineered sustained release local anesthetic construct successfully delivers bupivacaine for an extended period of time^3–5. This study is designed to evaluate the effect of the LA system on chondrocytes in an inflammatory OA-like environment.

Design:

Chondrocytes were cultured with bolus, liposomal, or construct LA and either untreated or treated with TNF-α and IL-1α for 24 hrs, 48 hrs, or 96 hrs. Chondrocyte viability, interleukin-8 (IL-8), interleukin-6 (IL-6), collagenase activity and proteoglycan deposition were assessed.

Results:

In the presence of the engineered construct, the chondrocytes retained viability and regenerative function. Moreover, the construct allowed for higher initial doses to be used, which promoted more regeneration and decreased inflammation without compromising cellular viability.

Conclusions:

The construct promotes a less hypertrophic chondrocyte environment while promoting a more anti-inflammatory environment. These two factors are consistent with a less OA progressive environment when using the engineered construct, compared to bolus LA.

"Thaumaturgy"- A Novel Behavior-shaping Technique

Aim

To compare and evaluate the effectiveness of thaumaturgy in alleviation of anxiety in children aged 2-13 years.

Materials and methods

Two hundred and forty children aged 2-13 years, identified as manifesting strong-willed behavior were selected for this study. The children were randomly assigned to be managed by one of the three thaumaturgic distraction techniques. Anxiety was assessed before and after the local anesthetic procedure using the anxiety facial scale.

Results

There was a significant decrease in anxiety with the use of thaumaturgic techniques. Thumb and light trick significantly reduced anxiety in children aged 2-7 years, book trick reduced anxiety in children aged 7-11 years, and item tricks in children aged 11-13 years.

Conclusion

The use of thaumaturgy plays an important role in shaping the behavior of a child in pediatric dentistry. The age and cognitive development of child dictates the technique to be used.

Clinical significance

Thaumaturgy helps to render effective dental treatment in uncooperative children and instill a positive attitude.

How to cite this article

Konde S, Sumaiyya S, Agarwal M, et al. "Thaumaturgy"-A Novel Behavior-shaping Technique. Int J Clin Pediatr Dent 2020;13(4):318-321.

[Autophagy activation attenuates the neurotoxicity of local anaesthetics by decreasing caspase-3 activity in rats]

BACKGROUND AND OBJECTIVES

The mechanisms by which local anesthetics cause neurotoxicity are very complicated. Apoptosis and autophagy are highly coordinated mechanisms that maintain cellular homeostasis against stress. Studies have shown that autophagy activation serves as a protective mechanism in vitro. However, whether it also plays the same role in vivo is unclear. The aim of this study was to explore the role of autophagy in local anesthetic-induced neurotoxicity and to elucidate the mechanism of neurotoxicity in an intrathecally injected rat model.

METHODS

Eighteen healthy adult male Sprague-Dawley rats were randomly divided into three groups. Before receiving an intrathecal injection of 1% bupivacaine, each rat received an intraperitoneal injection of vehicle or rapamycin (1 mg.kg^-1) once a day for 3 days. The pathological changes were examined by Haematoxylin and Eosin (HE) staining. Apoptosis was analysed by TdT-mediated dUTP Nick-End Labelling (TUNEL) staining. Caspase-3, Beclin1 and LC3 expression was examined by Immunohistochemical (IHC) staining. Beclin1 and LC3 expression and the LC3-II/LC3-I ratio were detected by western blot analysis.

RESULTS

After bupivacaine was injected intrathecally, pathological damage occurred in spinal cord neurons, and the levels of apoptosis and caspase-3 increased. Enhancement of autophagy with rapamycin markedly alleviated the pathological changes and decreased the levels of apoptosis and caspase-3 while increasing the expression of LC3 and Beclin1 and the ratio of LC3-II to LC3-I.

CONCLUSIONS

Enhancement of autophagy decreases caspase-3-dependent apoptosis and improves neuronal survivalin vivo. Activation of autophagy may be a potential therapeutic strategy for local anaesthetic-induced neurotoxicity.

LAW Trial - The Impact of Local Anesthetics Infiltration in Surgical Wound for Gastrointestinal Procedures (LAW): A Double-Blind, Randomized Controlled Trial

INTRODUCTION AND AIMS

Prior studies have suggested that infiltration of local anesthetics reduce the rate of surgical site infections (SSIs). Opioid usage has become an epidemic. Some analgesic modalities, such as epidural analgesia and transversus abdominis plane block are associated with shorter length of stay and lower opioid use. The aim of our study was to assess the relationship between local infiltration of bupivacaine with rates of SSI and pain control.

MATERIALS AND METHODS

We conducted a prospective, double-blinded randomized controlled trial in patients who underwent open major gastrointestinal procedures from July 2016 to June 2017. Patients were divided into two groups based on administration of 0.5% bupivacaine (n = 30) (group 1) or placebo (n = 30) (control group). Outcomes evaluated were SSI, postoperative opioid requirements and pain scores.

RESULTS

Patients in the bupivacaine group required a lower dose of epidural analgesia during the first 24 h (5.3 mcg/kg/h vs. 6.4 mcg/kg/h; p = 0.05). Opioid requirement was shorter in the bupivacaine group (3.5 ± 2.3 days vs. 5.7 ± 2.9 days; p = 0.01). No difference was found between groups in terms of SSI rates (0% vs. 6.7%, p = 0.49).

CONCLUSIONS

There is no clear association between bupivacaine infiltration and reduction of SSI rate according to our study. Wound bupivacaine infiltration is associated with a lower dose of epidural infusion and opioid requirements.

Ultrasound diagnosis of a case of transient bilateral vocal cord paralysis secondary to local anesthetic infiltration

One of the most important complications associated with thyroid and parathyroid surgery is vocal cord paralysis due to a recurrent laryngeal nerve injury. Recurrent laryngeal nerve injury paralysis induced by local anesthetics is a rare complication with very few published cases Various techniques are available for diagnosing vocal cord paralysis, including, flexible fiberoptic laryngoscopy, videostrobolaryngoscopy and indirect laryngoscopy. However, these techniques are expensive and are often associated with pain and discomfort among patients. Considering these disadvantages, transcutaneous laryngeal ultrasound is an alternative imaging tool for vocal cord examination in patients undergoing thyroid and parathyroid surgery. We describe a case which was sonographically diagnosed a transient bilateral vocal cord paralysis after the local infiltration of 10mL of 2% mepivacaine administered for the revision of the surgical wound due to a subcutaneous hematoma that occurred after a subtotal parathyroidectomy.

Effect of local anesthetics on viability and differentiation of various adult stem/progenitor cells

BACKGROUND

Local anesthetics (LAs) are widely used to control pain during various clinical treatments. One of the side effects of LAs, cytotoxicity, has been investigated in various cells including stem/progenitor cells. However, our understanding of the effects of LAs on the differentiation capacity of stem/progenitor cells still remains limited. Therefore, a comparative study was conducted to investigate the effects of multiple LAs on viability and multi-lineage differentiation of stem/progenitor cells that originated from various adult tissues.

METHOD

Multiple types of stem/progenitor cells, including bone marrow mesenchymal stem/progenitor cells (MSCs), dental pulp stem/progenitor cells (DPSCs), periodontal ligament stem/progenitor cells (PDLSCs), and tendon-derived stem/progenitor cells, were either obtained from a commercial provider or isolated from adult human donors. Lidocaine (LD) and bupivacaine (BP) at various doses (1×, 0.75×, 0.5×, and 0.25× of each physiological dose) were applied to the different stem/progenitor cells for an hour, followed by induction of fibrogenic, chondrogenic, osteogenic, and adipogenic differentiation. Live/dead and MTT assays were performed at 24 h after the LD or BP treatment. At 2 weeks, qRT-PCR was conducted to evaluate the gene expressions associated with differentiation. After 4 weeks, multiple biochemical staining was performed to evaluate matrix deposition.

RESULTS

At 24 h after LD or BP treatment, 1× and 0.75× physiological doses of LD and BP showed significant cytotoxicity in all the tested adult stem/progenitor cells. At 0.5×, BP resulted in higher viability than the same dose LD, with variance between cell types. Overall, the gene expressions associated with fibrogenic, chondrogenic, osteogenic, and adipogenic differentiation were attenuated in LD or BP pre-treated stem/progenitor cells, with notable dose-effect and dependence on types. In contrast, certain doses of LD and/or BP were found to increase specific gene expression, depending on the cell types.

CONCLUSION

Our data suggest that LAs such as LD and BP affect not only the viability but also the differentiation capacity of adult stem/progenitor cells from various anatomical sites. This study sheds light on stem cell applications for tissue regeneration in which isolation and transplantation of stem cells frequently involve LA administration.

Subcoracoid tunnel block as an alternative infraclavicular brachial plexus approach -a case series

BACKGRUOND

Magnetic resonance neurography shows the brachial plexus cords in the subcoracoid tunnel beneath the pectoralis minor. With an ultrasound scan along the brachial line, the brachial plexus cords in the subcoracoid tunnel can be targeted using an in-plane needle approach. We describe this new approach to the infraclavicular block called the "subcoracoid tunnel block."

CASE

Twenty patients were administered with the ultrasound-guided subcoracoid tunnel block for the below-elbow surgery. The contact of the needle tip with cords was visible in all 20 patients. With neurostimulation, the posterior cord was identified in 11 (55%) and medial cord in 9 (45%) patients on the first needle pass. The subcoracoid tunnel block was successful in 16 patients (80%).

CONCLUSIONS

Our case series shows that the subcoracoid tunnel block is an excellent alternative technique for the infraclavicular block. Its advantages include better needle-cord visibility and easy identification of the brachial plexus cords.

Topical agents: a thoughtful choice for multimodal analgesia

For over a thousand years, various substances have been applied to the skin to treat pain. Some of these substances have active ingredients that we still use today. However, some have been discontinued due to their harmful effect, while others have been long forgotten. Recent concerns regarding the cardiovascular and renal risk from nonsteroidal anti-inflammatory drugs, and issues with opioids, have resulted in increasing demand and attention to non-systemic topical alternatives. There is increasing evidence of the efficacy and safety of topical agents in pain control. Topical analgesics are great alternatives for pain management and are an essential part of multimodal analgesia. This review aims to describe essential aspects of topical drugs that physicians should consider in their practice as part of multimodal analgesia. This review describes the mechanism of popular topical analgesics and also introduces the most recently released and experimental topical medications.