Effect of esketamine on the EC50 of remifentanil for blunting cardiovascular responses to endotracheal intubation in female patients under general anesthesia: a sequential allocation dose-finding study

BACKGROUND

This study aimed to investigate the effect of esketamine on the dose-effect relationship between remifentanil and the cardiovascular response to endotracheal intubation during target-controlled infusion (TCI) of propofol.

METHODS

Patients underwent elective gynecological laparoscopic surgery under general anesthesia with endotracheal intubation, aged 18-65 years, American Society of Anesthesiologists class I or II, 18 kg/m2 ≤ body mass index ≤ 30 kg/m2, were randomly divided into the control (group C) and esketamine groups (group E). Before anesthesia induction, group E received an intravenous injection of 0.3 mg/kg of esketamine, while group C received an equal dose of physiological saline. TCI of propofol to the effect-site concentration (EC) of 3.0 μg/mL, and then TCI of remifentanil to the effect room and intravenous injection of rocuronium 0.6 mg/kg after MOAA/S was 0. Endotracheal intubation was performed after 2 min. Dixon's modified sequential method was used, and the initial EC of remifentanil was 3.0 ng/mL. The EC of remifentanil was determined according to the intubation response of the previous patient, with an adjacent concentration gradient of 0.3 ng/mL. The EC50 and EC95 values and their 95% confidence intervals (CIs) were determined using probit regression analysis.

RESULTS

The EC50 for cardiovascular response inhibition to endotracheal intubation using remifentanil was 3.91 ng/mL (95% CI: 3.59-4.33 ng/mL) and EC95 was 4.66 ng/mL (95% CI: 4.27-6.23 ng/mL) with TCI of propofol 3.0 μg/mL. After intravenous administration of 0.3 mg/kg of esketamine, the EC50 of remifentanil was 3.56 ng/mL (95% CI: 3.22-3.99 ng/mL) and EC95 was 4.31 ng/mL (95% CI: 3.91-5.88 ng/mL).

CONCLUSIONS

Combined with TCI of propofol 3.0 μg/mL for anesthesia induction, esketamine significantly reduced the EC50 and EC95 of remifentanil to inhibit the cardiovascular response to endotracheal intubation.

TRIAL REGISTRATION

The trial was registered in the Chinese Clinical Trials Registry ( www.chictr.org.cn ; registration number: ChiCTR2200064932; date of registration:24/10/2022).

Optical trapping of gold microparticles using linearly polarized, centrally obstructed Gaussian beams

Metallic microparticles larger than the illumination wavelength are commonly considered poor optical trapping candidates due to their high extinction coefficient. This paper presents a numerical and experimental study on the three-dimensional (3D) trapping of gold microparticles using a centrally obstructed Gaussian beam based on the T-matrix method. The range of particle size for stable optical trapping is determined. For the trapping numerical aperture of 1.32 and illumination wavelength of 1.064 µm, numerical analysis proves that 3D trapping of gold microparticles with a radius bigger than 1.0 µm can be readily achieved. By imprinting a digital lens to the spatial light modulator, we slightly defocus the centrally obstructed Gaussian beam to shift the trapping location to the focal plane for clear observation. Experimental results demonstrate stable trapping of gold microparticles with a radius greater than 1.4 µm at high-power illumination, agreeing well with the theoretical predictions. The presented work should be of interest to the community applying metallic microparticles to relevant research.

Zero-order free holographic optical tweezers

Holographic optical tweezers (HOTs) use spatial light modulators (SLM) to modulate light beams, thereby enabling the dynamic control of optical trap arrays with complex intensity and phase distributions. This has provided exciting new opportunities for cell sorting, microstructure machining, and studying single molecules. However, the pixelated structure of the SLM will inevitably bring up the unmodulated zero-order diffraction possessing an unacceptably large fraction of the incident light beam power. This is harmful to optical trapping because of the bright, highly localized nature of the errant beam. In this paper and to address this issue, we construct a cost-effective, zero-order free HOTs apparatus, thanks to a homemade asymmetric triangle reflector and a digital lens. As there is no zero-order diffraction, the instrument performs excellently in generating complex light fields and manipulating particles.

Video-assisted superior mediastinal lymphadenectomy for papillary thyroid cancer: a case report

Superior mediastinal lymph node metastases in papillary thyroid cancer are uncommon. The clinical characteristics and surgical strategy of superior mediastinal lymph node metastases remain unclear. Superior mediastinal lymphadenectomy can be accomplished either by a transcervical or transsternal approach. Transsternal approach for superior mediastinal lymphadenectomy can cause great damage; transcervical approach sometimes results in inadequate exposure. Here we report our experience of a papillary thyroid cancer patient with superior mediastinal lymph node metastases who underwent video-assisted superior mediastinal lymphadenectomy. A 49-year-old woman diagnosed with papillary thyroid cancer in left thyroid underwent unilateral lobectomy and ipsilateral central and lateral node dissection in the local hospital 4 years ago. Currently lymph node metastases were found in mediastinum and the right neck, some of which were adjacent to the right innominate vein. Unilateral lobectomy, ipsilateral central and lateral node dissection, and video-assisted superior mediastinal lymphadenectomy were successfully performed by transcervical approach. Subsequently, the patient received thyroxine suppression therapy and adjuvant radioiodine treatment. Video-assisted superior mediastinal lymphadenectomy, providing adequate exposure for a complete superior mediastinal lymphadenectomy, is proved to be safe and feasible.

Multi-color structured illumination microscopy for live cell imaging based on the enhanced image recombination transform algorithm

Structured illumination microscopy (SIM) has attracted considerable interest in super-resolution, live-cell imaging because of its low light dose and high imaging speed. Obtaining a high-quality reconstruction image in SIM depends on the precise determination of the parameters of the fringe illumination pattern. The image recombination transform (IRT) algorithm is superior to other algorithms in obtaining the precise initial phase without any approximation, which is promising to provide a considerable solution to address the difficulty of initial phase estimation at low-modulation-depth conditions. However, the IRT algorithm only considers a phase shift of π∕2, which limits its applications in general scenarios. In this letter, we present a general form of IRT algorithm suitable for arbitrary phase shifts, providing a powerful tool for parameter estimation in low signal-to-noise cases. To demonstrate the effectiveness of the enhanced IRT algorithm, we constructed a multicolor, structured illumination microscope and studied at super-resolution, the cargo traffic in HRPE cells, and monitored the movement of mitochondrial structures and microtubules in COS-7 cells. The custom SIM system using the enhanced IRT algorithm allows multicolor capability and a low excitation intensity fluorescence imaging less than 1 W/cm². High-quality super-resolution images are obtained, which demonstrates the utility of this approach in imaging in the life sciences.

Further evidence that a variant of the gene NUDT15 may be an important predictor of azathioprine-induced toxicity in Chinese subjects: a case report

WHAT IS KNOWN AND OBJECTIVE

Thiopurine methyltransferase (TPMT) enzyme is an important component in the metabolism of azathioprine (AZA). Its mutation may lead to AZA-induced toxicity. The dysfunctional genetic variant TPMT *3C is of low frequency among Asians. Moreover, AZA-induced toxicity still occurs in some patients with normal TPMT activity. This suggests that additional factors, including other genetic variants, may contribute to such toxicity. Recent studies described a strong association between a variant of the NUDT15, a gene that mediates the hydrolysis of some nucleoside diphosphate derivatives, and thiopurine-related myelosuppression in Asians. We report the first case of a Chinese patient with AZA-induced severe toxicity with no clinically significant TPMT variant but with the NUDT15 c.415C>T allele.

CASE SUMMARY

A 40-year-old Chinese patient with PBC-AIH overlap syndrome had been receiving for one month, azathioprine (50 mg/day) and methylprednisolone (24 mg/day) based on his TPMT*3C wild-type genotype. The patient developed serious myelosuppression and hair loss. AZA was stopped, and the patient was given liver-protective drugs and supportive treatment. TPMT and NUDT15 gene sequencing suggests that NUDT15 c.415C>T mutation was the likely cause of the adverse reaction.

WHAT IS NEW AND CONCLUSION

NUDT15 c.415C>T may be another predictor of AZA-induced leukocytopenia. If further well-controlled studies validate this association with sufficient predictive power, NUDT15 and TPMT genotyping before starting AZA treatment may become appropriate.

Sperm aneuploidy and implications for genetic counseling in a pedigree of three t(1;3) balanced translocation carriers

A reciprocal translocation between the short arm of chromosome 1 and the long arm of chromosome 3 was observed in a pedigree of three carriers (proband, and his brother and mother). In this study, the three carriers had different clinical manifestations: the proband with infertility, his brother with spousal miscarriages, and his mother with no adverse reproductive history. Cytogenetic analysis of metaphase chromosomes was performed, and triple-color fluorescence in situ hybridization was applied to the detection of aneuploidy sperm related to the interchromosomal effect (ICE). An increase of aneuploidy of chromosome 21 in the proband and aneuploidy of chromosomes 13, 21, and Y in the brother were observed. Since patients with reciprocal translocations and spermatogenetic impairment are candidates, with their partners, for intracytoplasmic sperm injection, the study of the level of sperm aneuploidy rates would provide useful information for couples at risk, as well as contributing to a better understanding of the ICE.

Analysis of regulatory T cells frequency in peripheral blood and tumor tissues in papillary thyroid carcinoma with and without Hashimoto's thyroiditis

PURPOSE

Regulatory T cells (Treg) suppress the immune reaction. The aim of the present study was to investigate the clinicopathologic significance and roles of Treg in papillary thyroid carcinoma (PTC) patients with and without Hashimoto's thyroiditis.

METHODS

Flow cytometry was used to detect the percentage of CD4+CD25+CD127low/- Treg among CD4+ T cells in peripheral blood. FoxP3+ Treg were detected by immunohistochemistry in the tumor tissues.

RESULTS

The percentage of CD4+CD25+CD127low/- Treg among CD4+ T cells was significantly higher in PTC patients than that in multinodular goiter (MNG) patients. There were large numbers of tumor-infiltrating FoxP3+ Treg in primary PTC and metastatic lymph nodes tissues; however, there was no FoxP3 expression in the MNG tissues. Higher percentage of Treg both in peripheral blood and tumor tissues was associated with extrathyroidal extension and lymph nodes metastasis. The percentage of CD4+CD25+CD127low/- Treg among CD4+ T cells in peripheral blood of PTC patients with Hashimoto's thyroiditis (HT) was significantly lower, whereas the infiltration of FoxP3+ Treg in tissues of PTC with HT tended to be increased.

CONCLUSIONS

We concluded that the percentage of Treg increased in peripheral blood as well as in the tumor tissues of PTC patients compared with that of MNG patients. The high percentage of Treg was associated with aggressiveness. There may be a compensatory expansion of Treg at the sites of inflammation in tissues of PTC with HT contributing to the immune response suppression.

Reproductive outcomes in recurrent pregnancy loss associated with a parental carrier of chromosome abnormalities or polymorphisms

The subsequent reproductive outcomes in couples with a history of recurrent pregnancy loss (RPL) associated with chromosome abnormalities or polymorphisms are generally not reported in China. Many RPL carrier couples have decided not to have children. The present study recorded the subsequent delivery, miscarriage, and unpregnancy outcomes of 113 RPL carrier couples and 226 non-carrier couples, and compared differences in reproductive outcomes between couples with different types of chromosome abnormalities or polymorphisms and chromosome normal couples. Our results showed that couples with RPL associated with parental chromosome abnormalities or polymorphisms did not have significantly lower live birth rates than non-carrier couples in China. These results suggest the current guidance given to Chinese RPL couples.

Epidural anaesthesia with goal-directed administration of ropivacaine improves haemodynamic stability when combined with general anaesthesia in elderly patients undergoing major abdominal surgery

The use of epidural ropivacaine may result in significant haemodynamic fluctuations during combined epidural and general anaesthesia. We designed this study to investigate whether epidural anaesthesia with a goal-directed approach, when combined with general anaesthesia, improved haemodynamic stability in elderly patients undergoing major abdominal surgery. Seventy-five elderly patients undergoing major abdominal surgery were randomly and evenly assigned to one of three groups receiving intraoperative epidural anaesthesia with either ropivacaine 0.1% (Group 1), ropivacaine 0.375% (Group 2) or ropivacaine 0.375% for abdominal wall pain and ropivacaine 0.1% for visceral pain (Group 3). General anaesthesia was induced using a target-controlled infusion of combined propofol and remifentanil. The remifentanil target concentration was adjusted according to the mean arterial pressure and heart rate, and vasoactive agents were administered to maintain stable haemodynamics. The need for vasoactive drug administrations was 1.4 (standard deviation 0.9) in Group 3 (n=24), representing a significantly lower frequency of administration compared with Groups 1 (n=24) and 2 (n=24) (P <0.05 versus Group 1; P <0.01 versus Group 2). The total intraoperative dose of remifentanil was significantly greater in Group 1 (P <0.01 versus Group 2; P <0.05 versus Group 3) but did not differ significantly between Groups 2 and 3. Goal-directed epidural anaesthesia with different ropivacaine concentrations can improve haemodynamic stability when combined with general anaesthesia for elderly patients undergoing major abdominal surgery.

Strengthening of a model composite restoration using shape optimization: a numerical and experimental study

OBJECTIVE

This study aims to validate a cavity shape optimization approach for improving the debonding resistance of dental restorations by carrying out fracture tests on restored model teeth with standard and optimized cavity designs.

METHOD

The bio-mimetic stress-induced material transformation (SMT) optimization method was incorporated into the finite element (FE) program ABAQUS as a user material (UMAT) subroutine. The method uses stress minimization to optimize the cavity shape of a MOD restoration in an artificial premolar with special reference to the tooth-restoration interface under occlusal loads. The mechanical performance of the optimized design was first verified through FE analysis and then compared with that of the conventional design using fracture tests on model teeth.

RESULTS

The SMT optimization process indicated a T-shape cavity as a more favorable design for the MOD restoration in the artificial premolar. Compared with the conventional parallel wall, or undercut design, the T-shape cavity was shown numerically to reduce the interfacial stresses by up to 69%, and experimentally to increase the mean debonding resistance of the model teeth by 23% (p<0.05).

SIGNIFICANCE

Cavity shape optimization can help increase the debonding resistance of restored teeth by reducing the interfacial stresses between tooth and restoration under occlusal loads.

[Effect of occlusal interference on fluctuation of body's gravity center]

OBJECTIVE

To study if the occlusal interference affects the fluctuation of body's gravity center.

METHODS

An artificial occlusal interference was separately applied on 14 volunteers (7 males and 7 females, mean age 23.2 years). Fluctuations of body's gravity center were measured before wearing the occlusal interference appliance, at 30 minutes and 24 hours after wearing the appliance.

RESULTS

The length and area of fluctuation of body's gravity center with the interference appliance were greater than that without it. The length of fluctuation of gravity center was 40.22 cm, 41.66 cm and 43.21 cm in eye-opening conditions and 56.96 cm2, 61.93 cm2, 66.9 cm2 in eye-closing condition. The area of fluctuation of gravity center was 3.3 cm2, 3.43 cm2, 3.61 cm2 in eye-opening condition and 4.63 cm2, 5.00 cm2, 6.47 cm2 in eye-closing condition. The female volunteers showed more changes than the male ones.

CONCLUSION

Occlusal interference does affect the fluctuation of body's gravity center.

Needs of people with disabilities used to determine clinical education

Western rehabilitation techniques were first introduced into China in the early 1980s. The predominantly 'medical model' of health care in China has resulted in a shortage of rehabilitation personnel and limited experience determining the needs of clients. Occupational therapy practitioners in China are learning their new roles and clients, having never had any contact with occupational therapy, are unaware what services can be offered. The purpose of this research was to determine the most frequently self-identified functional problems (in the ares of self-care productivity and leisure) identified by 113 in-patients in four different hospitals in China, in order to assist therapists to develop programmmes that are responsive to clients' needs. Using the Canadian Occupational Performance Measure, both males and females identified significantly more self-care than leisure or productivity problems (P = 0.01). Females identified more productivity problems than males (P = 0.01) while males appeared to consider leisure difficulties as a priority more frequently than women. The study was jointly undertaken by a Canadian and a Chinese researcher. To our knowledge, this is the first time that occupational therapy personnel in China have formally surveyed clients about their rehabilitation needs, in order to develop priorities for programming.