Regiodivergent metal-catalyzed B(4)- and C(1)-selenylation of o-carboranes.

Regiodivergent transition metal-catalyzed B(4)- and C(1)-selenylation reactions of o-carboranes have been demonstrated. Namely, Ru(ii)-catalysis selectively generated B(4)-selenylated o-carboranes from the reaction of o-carborane acids with arylselenyl bromides with the release of carbon dioxide. In contrast, Pd(ii) catalysis provided exclusively C(1)-selenylated o-carboranes from the decarboxylative reaction of o-carborane acids with diaryl diselenides. In contrast to previous milestones in this area, these reactions demonstrate broad substrate scope with excellent yields. Combination of these methods leads to the formation of B(4)-C(1)-diselenylated o-carboranes. DFT studies revealed the mechanism of the Ru-process, with initial selenylation of the carborane cluster discovered to be essential for an energetically reasonable decarboxylation. This results in selenylation on the B(4) position prior to the decarboxylation event at C(1). This contrasted with the Pd-process in which the ready decarboxylation at C(1) leads to selenylation at C(1).

Synthesis of o-Carborane-Fused Pyrazoles through Sequential C-N Bond Formation.

Transition-metal-free synthetic method for o-carborane-fused pyrazoles as a new scaffold has been developed from the reaction of B(4)-acylmethyl or B(3,5)-diacylmethyl o-carborane with 2-azido-1,3-dimethylimidazolinium hexafluorophosphate (ADMP) in the presence of DBU in acetonitrile through sequential diazotization and cyclization reaction in one pot, consequently allowing twofold C-N bond formation under extremely mild conditions and high functional group tolerance.

Regional analgesia techniques for video-assisted thoracic surgery: a frequentist network meta-analysis / 대한마취과학회지

Background@#Various regional analgesia techniques are used to reduce postoperative pain in patients undergoing video-assisted thoracic surgery (VATS). This study aimed to determine the relative efficacy of regional analgesic interventions for VATS using a network meta-analysis (NMA). @*Methods@#We searched the Medline, EMBASE, Cochrane Controlled Trial Register, Web of Science, and Google Scholar databases to identify all randomized controlled trials (RCTs) that compared the analgesic effects of the following interventions: control, thoracic paravertebral block (TPVB), erector spinae plane block (ESPB), serratus plane block (SPB), and intercostal nerve block (INB). The primary outcome was opioid consumption during the first 24-h postoperative period. Pain scores were also collected during three different postoperative periods: the early (0–6 h), middle (6–18 h), and late (18–24 h) periods. @*Results@#A total of 21 RCTs (1391 patients) were included. TPVB showed the greatest effect on opioid consumption compared with the control (mean difference [MD] = −13.2 mg; 95% CI [−16.2, −10.1]). In terms of pain scores in the early period, ESPB had the greatest effect compared to control (MD = −1.6; 95% CI [−2.3, −0.9]). In the middle and late periods, pain scores showed that TPVB, ESPB and INB had superior analgesic effects compared to controls, while SPB did not. @*Conclusions@#TPVB had the best analgesic efficacy following VATS, though the analgesic efficacy of ESPBs was comparable. However, further studies are needed to determine the optimal regional analgesia technique to improve postoperative pain control following VATS.

Iridium-Catalyzed Cage B(4)-Amidation Reaction of o-Carboranes with Dioxazolones: Selective Synthesis of Amidated o-Carboranes and Amidated and Methoxycarbonylated nido-Carboranes.

Described is the Ir-catalyzed cage B(4)-amidation of o-carboranes with dioxazolones by carboxylic acid-assisted B(4)-H bond activation under extremely mild conditions, affording amidated o-carboranes and amidated and methoxycarbonylated nido-carboranes through sequential B(4)-amidation, O-methylation, and B(3)-deboronation in one pot. Carboxylic acid used as a directing group after the cage B(4)-amidation is efficiently trapped by trimethylsilyldiazomethane instead of undergoing decarboxylation. Mechanism studies demonstrated that the O-methylation through trapping of acid occurred first, followed by the B(3)-deboronation.

The Sonozotz project: Assembling an echolocation call library for bats in a megadiverse country.

Bat acoustic libraries are important tools that assemble echolocation calls to allow the comparison and discrimination to confirm species identifications. The Sonozotz project represents the first nation-wide library of bat echolocation calls for a megadiverse country. It was assembled following a standardized recording protocol that aimed to cover different recording habitats, recording techniques, and call variation inherent to individuals. The Sonozotz project included 69 species of echolocating bats, a high species richness that represents 50% of bat species found in the country. We include recommendations on how the database can be used and how the sampling methods can be potentially replicated in countries with similar environmental and geographic conditions. To our knowledge, this represents the most exhaustive effort to date to document and compile the diversity of bat echolocation calls for a megadiverse country. This database will be useful to address a range of ecological questions including the effects of anthropogenic activities on bat communities through the analysis of bat sound.

Costoclavicular brachial plexus block reduces hemidiaphragmatic paralysis more than supraclavicular brachial plexus block: retrospective, propensity score matched cohort study

Background@#Hemidiaphragmatic paralysis, a frequent complication of the brachial plexus block performed above the clavicle, is rarely associated with an infraclavicular approach. The costoclavicular brachial plexus block is emerging as a promising infraclavicular approach. However, it may increase the risk of hemidiaphragmatic paralysis because the proximity to the phrenic nerve is greater than in the classical infraclavicular approach. @*Methods@#This retrospective analysis compared the incidence of hemidiaphragmatic paralysis in patients undergoing costoclavicular and supraclavicular brachial plexus blocks. Of 315 patients who underwent brachial plexus block performed by a single anesthesiologist, 118 underwent costoclavicular, and 197 underwent supraclavicular brachial plexus block. Propensity score matching selected 118 pairs of patients. The primary outcome was the incidence of hemidiaphragmatic paralysis, defined as a postoperative elevation of the hemidiaphragm > 20 mm. Factors affecting the incidence of hemidiaphragmatic paralysis were also evaluated. @*Results@#Hemidiaphragmatic paralysis was observed in three patients (2.5%) who underwent costoclavicular and 47 (39.8%) who underwent supraclavicular brachial plexus blocks (P < 0.001; odds ratio, 0.04; 95% confidence interval, 0.01-0.13). Both the brachial plexus block approach and the injected volume of local anesthetic were significantly associated with hemidiaphragmatic paralysis. @*Conclusions@#The incidence of hemidiaphragmatic paralysis is significantly lower with costoclavicular than with supraclavicular brachial plexus block.

Trigeminocardiac reflex: sudden severe bradycardia during open reduction for temporomandibular joint dislocation: A case report

BACKGROUND: The trigeminocardiac reflex (TCR), which occurs after stimulation of the territory of the trigeminal nerve, is very rarely reported to be caused by stimulation of the mandibular branch. We report a case of TCR in open reduction for temporomandibular joint (TMJ) dislocation. CASE: A 74-year-old female presented for TMJ dislocation. During open reduction of TMJ under general anesthesia, severe bradycardia (15 beats/min) occurred. Immediately 0.5 mg atropine was administered intravenously, and the surgical manipulation was stopped. After 30 seconds, heart rate normalized. During surgery, severe bradycardia occurred one more time. It disappeared spontaneously as soon as surgical manipulation was stopped. The surgery was completed uneventfully. CONCLUSIONS: Because of the possibility of profound bradycardia, asystole, or even death when evoked, it is important to be aware of the trigeminocardiac reflex during manipulation of the mandibular divisions, especially during surgical stimulation of the TMJ.

Appropriate angle and depth in thoracic transforaminal epidural block in Koreans

BACKGROUND: Selective transforaminal epidural block has come to the for as a targetspecific modality in the treatment and diagnosis of spinal pain. Thoracic transforaminal epidural block (TTFEB) has the associated risk of pneumothorax. This article describes a retrospective study conducted using computed tomography (CT) imaging to investigate the TTFEB angle and depth appropriate to minimize the risk of pneumothorax in Koreans. METHODS: The subjects of the present study were 100 randomly selected patients between 50 and 70 years of age found be free of thoracic disease according to chest CT performed in the present hospital. On the chest CT, the superior, middle, and inferior thoracic vertebrae were observed at the T2, T7, and T11 levels, respectively. RESULTS: The average distance and the needle insertion angle from the skin point at which the needle may be inserted without piercing the lung to the intervertebral foramen were 117.8 ± 12.1 mm and 58.1 ± 6.1° at the T2 level, 85.6 ± 10.0 mm and 61.7 ± 4.3° at the T7 level, and 94.3 ± 8.7 mm and 64.4 ± 7.0° at the T11 level, respectively. CONCLUSIONS: The needle insertion at the point further than 40 mm, on the upper, middle thorax, if the needle pass from the inner vertebral body to lamina, it could be safer. However, on the lower thorax, needle could pierce the lung though the needle start from the inner vertebral body. Thus, it can be safer if the needle pass toward the exterior margin of lamina.

Acute neck pain due to crowned dens syndrome: A case report

Crowned dens syndrome (CDS) is a cause of neck pain characterized by calcium deposition in the periodontoid tissues. Clinical features of the syndrome are acute onset of neck pain and headache with fever. Computed tomographic imaging is necessary for diagnosis. The prognosis of CDS is excellent. Symptoms disappear within several weeks and calcifications may be absorbed. We report a case of CDS with acute onset of severe neck pain, facial pain, and pharyngeal pain provoked by swallowing.

Effect of dexmedetomidine on endotracheal intubating conditions during endotracheal intubation without neuromuscular blocker following propofol/remifentanil

BACKGROUND: In the present study, we investigated the effect of dexmedetomidine on the intubating conditions and hemodynamic changes during endotracheal intubation following anesthetic induction performed using propofol and remifentanil without a neuromuscular blocking agent. METHODS: We selected 70 adult patients aged 20 to 65 years scheduled to undergo general anesthesia. Induction was performed using 2 mg/kg of propofol and 1.5 µg/kg of remifentanil. The patients were divided into two groups, a dexmedetomidine group (Group D) and a control group (Group C). Group D received an infusion of dexmedetomidine 1 µg/kg for 10 minutes before induction, and Group C received the same volume of normal saline infused in the same manner. Intubating conditions were evaluated and blood pressure and heart rate were recorded at various time points to assess hemodynamic stability. RESULTS: Intubating conditions were evaluated as excellent for 34 patients and good for 1 patient in Group D, and excellent for 4 patients, good for 20 patients, poor for 4 patients, and bad for 7 patients in Group C (P < 0.001). The heart rate was significantly lower in Group D than in Group C at all measurement times. The mean arterial blood pressure was significantly lower in Group C than in Group D at 10 minutes after dexmedetomidine administration (P = 0.049), after the induction of anesthesia (P < 0.001), immediately after endotracheal intubation (P = 0.008), and 3 minutes after endotracheal intubation (P < 0.001). CONCLUSIONS: Dexmedetomidine 1 µg/kg improved the intubating conditions and stabilized hemodynamic changes following anesthetic induction performed using propofol 2 mg/kg and remifentanil 1.5 µg/kg without a neuromuscular blocking agent.

Successful Treatment of Occipital Radiating Headache Using Pulsed Radiofrequency Therapy

Rheumatoid arthritis (RA) is a chronic inflammatory disease involving multiple joints. The cervical spine is often affected, and cases involving atlantoaxial joint can lead to instability. Anterior atlantoaxial subluxation in RA patients can lead to posterior neck pain or occipital headache because of compression of the C2 ganglion or nerve. Here, we report the successful treatment of a RA patient with occipital radiating headache using pulsed radiofrequency therapy at the C2 dorsal root ganglion.

Comparison of etomidate and propofol on intubating conditions and the onset time associated with cisatracurium administration / 대한마취과학회지

BACKGROUND: This study compared intubating conditions and the onset time associated with administration of cisatracurium, a nondepolarizing neuromuscular blocker with a relatively slow onset, according to prior injection of one of two intravenous anesthetic agents: propofol or etomidate. METHODS: Forty-six female patients, undergoing general anesthesia and endotracheal intubation for elective surgery, were randomized to two groups; group P were administered propofol (2 mg/kg) prior to cisatracurium (0.2 mg/kg); group E were administered etomidate (0.3 mg/kg) prior to cisatracurium (0.2 mg/kg). We measured intubating conditions and the onset time according to the types of intravenous anesthetic administered. Measurements of heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were taken immediately prior to induction; immediately and 1 min after IV anesthetic administration; and immediately and 1, 2, 3, 4, 5, 7, and 15 min after endotracheal intubation. RESULTS: Intubating conditions were superior in group E compared with group P (P = 0.009). The average onset time of cisatracurium was more rapid in group E (155.74 +/- 32.92 s vs. 185.26 +/- 38.57 s in group P; P = 0.008). There were no group differences in SBP, DBP, and HR following intravenous anesthetic drug injection and endotracheal intubation. However, SBP and DBP were substantially higher in group E after endotracheal intubation. CONCLUSIONS: Etomidate improves intubating conditions and provide a more rapid onset time of cisatracurium during anesthetic induction compared to propofol.

Spinal anesthesia during cesarean section in a liver transplant recipient: A case report

Liver transplantation (LT) has been widely performed and has become the treatment of choice in patients with medically non-treatable liver disorders. With surgical and medical advancements, LT recipients are now able to live a near-to-normal life. Pregnancy has also become possible in female LT patients. However, there are still several potential risk factors that must be considered in these particular patients. LT patients have a higher risk of anesthesia and are at high risk for delivering babies with prematurity and low birth weight. We report a case of successful spinal anesthesia in a 31-year-old LT patient for cesarean section.

Alexithymia and the Recognition of Facial Emotion in Schizophrenic Patients

OBJECTIVES: Schizophrenic patients have been shown to be impaired in both emotional self-awareness and recognition of others' facial emotions. Alexithymia refers to the deficits in emotional self-awareness. The relationship between alexithymia and recognition of others' facial emotions needs to be explored to better understand the characteristics of emotional deficits in schizophrenic patients. METHODS: Thirty control subjects and 31 schizophrenic patients completed the Toronto Alexithymia Scale-20-Korean version (TAS-20K) and facial emotion recognition task. The stimuli in facial emotion recognition task consist of 6 emotions (happiness, sadness, anger, fear, disgust, and neutral). Recognition accuracy was calculated within each emotion category. Correlations between TAS-20K and recognition accuracy were analyzed. RESULTS: The schizophrenic patients showed higher TAS-20K scores and lower recognition accuracy compared with the control subjects. The schizophrenic patients did not demonstrate any significant correlations between TAS-20K and recognition accuracy, unlike the control subjects. CONCLUSIONS: The data suggest that, although schizophrenia may impair both emotional self-awareness and recognition of others' facial emotions, the degrees of deficit can be different between emotional self-awareness and recognition of others' facial emotions. This indicates that the emotional deficits in schizophrenia may assume more complex features.