[Efficacy and safety analysis of bupivacaine liposome for pericapsular nerve group block for postoperative analgesia in elderly patients with hip replacement]

Objective: To investigate the efficacy and safety of bupivacaine liposome for pericapsular nerve group block (PENGB) for postoperative analgesia in elderly patients with total hip replacement. Methods: A total of 42 elderly patients underwent total hip replacement were selected in the Second Affiliated Hospital of Wenzhou Medical University from May to July in 2023, including 19 males and 23 females, aged (68.8±6.3) years, the American Society of Anesthesiologists (ASA) grade Ⅰ to Ⅲ. They were divided into bupivacaine liposome group (observation group) and levobupivacaine hydrochloride group (control group) according to random number table, with 21 cases in each group. All the patients were anesthetized by lumbar anesthesia combined with PENGB. During PENGB, the observation group was injected with 10 ml (133 mg) bupivacaine liposome+5 ml normal saline, and the control group was injected with 10 ml (75 mg) levobupivacaine hydrochloride+5 ml normal saline. The primary outcome measures included the rest and movement visual analogue scale (VAS) scores at 6, 12, 24, 36, 48, 60, and 72 h after operation, the sufentanil consumption in analgesic pump, the numbers of analgesic pump compressions, and the rates of additional parexib sodium use in ward. The secondary outcome measures were the changes in lower limb muscle strength, the length of hospital stay and the occurrence of adverse reactions. Results: There was no significant difference in the rest and movement VAS scores between the two groups at pre-operation and at 6 h after operation (P>0.05);but the rest and movement VAS scores at 12, 24, 36, 48, 60 and 72 h after operation in observation group were significantly lower than those in control group (P<0.05); the rest and movement VAS scores at 6, 12, 24, 36, 48, 60 and 72 h after operation were lower than those at pre-operation in two group (P<0.05). The consumption of sufentanil in analgesic pump and parexib sodium usage in observation group were lower than those in control group at 12, 24, 36 and 48 h after operation (P<0.05). The total number of analgesic pump compressions, the number of effective compressions and the number of ineffective compressions in 48 h in observation group were lower than those in control group (P<0.05). The muscle strength of the lower limbs of all patients were able to move against gravity at 12 h after operation. The incidence of nausea in 48 h after operation in observation group was 9.5% (2/21), which was lower than 42.9% (9/21) in control group (P=0.014). No postoperative vomiting occurred in all patients. The length of the hospital stay was (9.3±2.2) d in observation group and (8.9±1.9) d in control group, and there was no significant difference between the two groups (P=0.500). Conclusion: Compared with levobupivacaine hydrochloride, liposomal bupivacaine in PENGB provides analgesic effects for up to 72 h after total hip replacement in elderly patients, reduces postoperative opioid and other analgesics usage, decreases the incidence of postoperative nausea, and has a minor effect on lower limb movement without prolonging hospitalization.

Otolith microchemistry reveals diverse habitat uses and migratory patterns of two Coilia species (Engraulidae) in the Min River Estuary, southern China

A recent study based on gonad histology revealed that the existence of the spawning grounds for Gray's grenadier anchovy (Coilia grayii) and Osbeck's grenadier anchovy (C. mystus) in the Min River Estuary, the largest in Fujian Province, southern China. Further confirming their natal sources and migratory patterns is essential to understand their life histories. We used otolith microchemistry to assess the origins and habitat uses of 23 C. grayii and 22 C. mystus, collected the Min River Estuary and the adjacent waters. The results showed that C. grayii spawned in both freshwater (n‍ = 14) and brackish water (n = 9), and C. mystus spawned mainly in brackish water (n‍ = 20) with minor in freshwater (n‍ = 1) and marine water (n‍ = 1). The migratory patterns of C. grayii (four types) and C. mystus (five types) were diverse, mainly exhibiting anadromous and semi-anadromous behaviors. The first migratory behavior of C. grayii and C. mystus occurred within the age of the first year. The findings have significant implications for fishery stock management of the Min River Estuary and its adjacent waters.

[Hybrid schwannoma/perineurioma: a clinicopathological analysis of 35 cases]

Objective: To investigate the clinical pathological features, pathological diagnosis and differential diagnosis of hybrid schwannoma/perineurioma. Methods: The clinicopathological data of 35 cases were collected at Fudan University Shanghai Cancer Center, from October 2010 to August 2017; morphological observation and immunohistochemical staining were performed, and the literatures were also reviewed. Results: There were 7 males and 28 females (male∶female=1∶4), patients with onset age ranging from 3 to 81 years(mean=36 years). Of 35 tumors, 11 cases occurred in the head and neck, 10 in the extremities, 9 in the trunk, 4 in the intestine, and 1 in the labiamajora, respectively. Clinically, most patients presented as a slowly growing dermal nodule, sometimes associated with pain. The duration of symptoms ranged from 1 month to 20 years before excision. Tumor size ranged from 0.8 cm to 6.0 cm (mean=2.6 cm). Microscopically, the tumors were usually well circumscribed but unencapsulated. At low power, most tumors were located in the dermis or subcutis, and several cases in the submucosal tissues. The tumors were composed of fascicular, storiform or whorled growth of closely intermixed plump spindle cells and slender spindle cells. The plump spindle cells had ill-defined eosinophilic cytoplasm with larger tapered or wavy nuclei, whereas the slender spindle cells had comparatively delicate nuclei with elongated cytoplasmic processes. Tumor cells had no obvious atypia, and mitoses were rare. Scattered large cells with degenerative nuclear atypia were seen in some cases. By immunohistochemistry, most of plump spindle cells showed strong staining of S-100 protein(35/35) and SOX10(8/9), whereas slender spindle cells stained variably for epithelial membrane antigen(31/35), CD34(32/33), Claudin-1 (15/15) and GLUT-1(8/8). Ki-67 proliferation index were all less than 5%. Follow-up data available in 16 patients (range 4 to 72 months; mean=46 months) were all free of disease, and one case developed local recurrence. Conclusions: Hybrid schwannoma/perineuriomaisa benign nerve sheath tumor that typically manifests as a dermaland subcutaneous tumor, less frequently may affect uncommon sites such as the nasal cavity, the gastro-intestinal tract, and the external genital areas. The tumors consisted of intimately admixed plump-spindled schwannian cells and slender-spindled perineurial cells showing dual differentiation of strong S-100 protein and SOX10 expression in the former component and variable immunoreactivity of epithelial membrane antigen, Claudin-1 and CD34 in the latter. It should be aware of the possibility of potentially misinterpretation of hybrid schwannoma/perineurioma as dermatofibrosarcoma protuberans and solitary fibrous tumor and so on.

Risk factors and score for recollapse of the augmented vertebrae after percutaneous vertebroplasty in osteoporotic vertebral compression fractures

Our study demonstrated a high incidence of recollapse of the augmented vertebrae after PVP treatment for OVCFs. A risk score based on all significant factors can predict the rate of recollapse and gain clinical benefits to prevent recollapse in patients at high risk.

BACKGROUND

Recollapse of the augmented vertebrae after percutaneous vertebroplasty (PVP) treatment for osteoporotic vertebral compression fractures (OVCFs) has obtained much attention. However, little is known about risk factors and score for recollapse of the augmented vertebrae.

OBJECTIVE

To determine risk factors and furthermore develop a risk score related to recollapse of the augmented vertebrae after PVP treatment for OVCFs.

METHODS

Patients who were treated with PVP for single OVCFs and met this study's inclusion criteria were retrospectively reviewed. The follow-up period was at least 2 years. Associations of recollapse with co-variates (age, gender, bone mass density [BMD] with a T-score, fracture level, intravertebral cleft [IVC], fracture type, cement volume, cement leakage, leakage into a disc, cement distribution pattern, Non-PMMA-endplate-contact [NPEC], preoperative fracture severity, reduction rate [RR], reduction angle [RA]) were analyzed and a risk score for recollapse was further developed to predict recollapse.

RESULTS

A total of 152 patients were included. Recollapse group was found in 42 (27.6%) patients. Preoperative IVC, solid lump cement distribution pattern, more RR (a cutoff value of 7%) and larger RA (a cutoff value of 3°) was significantly associated with increased risk for recollapse of the augmented vertebrae. A risk score was developed based on the number of risk factors present in each patient. Patients with a score of 4 had an approximately ninefold increased risk of developing recollapse over patients with a score of 0. The receiver operating characteristic curve of the risk score generated an area under the curve of 0.899 (95% CI 0.642-0.836, P = 0.000).

CONCLUSION

A risk score based on preoperative IVC, cement distribution pattern, reduction rate, and reduction angle predicts the rate of recollapse. Additional studies should aim to validate this score and inspect clinical benefits of recollapse prophylaxis in patients at high risk.

Density functional theory study of oxygen reduction reaction on Pt/Pd3Al(111) alloy electrocatalyst

Developing efficient catalysts for the oxygen reduction reaction (ORR) to reduce cathode Pt loading without sacrificing the performance has been under intensive research. Herein, by using density functional theory calculations, the activity and stability of a Pt monolayer supported on Pd3Al(111) as the ORR catalyst have been systematically studied. The simulations demonstrate that due to alloying, the ORR intermediates bind weakly on Pt/Pd3Al(111) with optimal adsorption energy of O and OH. By considering the elemental ORR steps, the ORR mechanism is predicted to be an OOH dissociation mechanism. The rate determining step is OOH dissociation with a reaction barrier of 0.37 eV, lower than the corresponding value on Pt/Pt3Al(111) and Pt(111), indicating the superior activity of Pt/Pd3Al(111). Even considering the unfeasible H adsorption under high potential, the ORR mechanism on Pt/Pd3Al(111) would proceed via O2 hydration, OOH hydration, H2O formation, and H2O desorption, indicating a good ORR electrocatalyst. Furthermore, stability was evaluated by calculating the alloy formation energy and the electrochemical potential shift of surface Pt dissolution. The exceptionally negative alloy formation energy of Pd3Al and the positive dissolution potential shift of the surface Pt atoms show the enhanced durability of Pt/Pd3Al(111). The improved activity, in combination with its enhanced stability, makes the novel ternary alloy electrocatalyst very promising for development of new cathode catalysts for fuel cells.

The segregation resistance of the Pt2ML/Os/Pd3Al sandwich catalyst for oxygen reduction reaction: a density functional theory study

Pt_1ML/Pd₃Al, which comprises a Pd₃Al core protected by a Pt monolayer, may experience Al dealloying because of the strong affinity of Al toward O. To circumvent this issue, the Pt_2ML/Os/Pd₃Al catalyst has been designed to suppress the migration of Al by inserting an Os monolayer at the interface between the Pd₃Al core and two Pt monolayers. On the basis of segregation energies, Al leaching from the core to the 1st layer is determined to be endothermic even under O coverage, indicating an energetic preference for Al to reside in the core structure. The Pt_2ML/Os/Pd₃Al catalyst benefits from the energetic disadvantage of the inward movement of Os and the presence of the 2 ML Pt layer. As an ORR electrocatalyst, the relatively weak adsorption ability of Pt_2ML/Os/Pd₃Al suggests improved ORR activity. Finally, a representative OOH association mechanism with low reaction barriers of 0.46, 0.31, 0.38 and 0.41 eV for the OOH formation, OOH dissociation, OH formation and H₂O formation steps suggests that the catalyst can effectively activate the O-O bond and eliminate OH, which can act as a catalytic poison. These findings suggest the design of stable sandwich catalysts as potential candidates for ORR electrocatalysis.

Complete mitochondrial genome and the phylogenetic position of the bighead pennah croaker Pennahia macrocephalus (Perciformes: Sciaenidae)

The complete mitogenome of the bighead pennah croaker Pennahia microcephalus was first determined in this study. It is 16,508 bp in length with the typical gene order and transcriptional direction in vertebrates containing 37 genes. The overall nucleotide composition is 27.5% A; 31.2% C; 16.0% G, and 25.3% T. The sizes of the 22 tRNA genes range from 68 to 75 bp. Two start (ATC and ATG) and three stop (AGA, TAG, and TAA/TA/T) codons were found in the protein-coding genes. In the Bayesian tree, all nodes were strongly supported based on the complete mitogenomes of 16 species from the family Sciaenidae. The phylogenetic results suggested P. macrocephalus has the closest relationship to the silver croaker P. argentata, a species from the same genus.

SUPRAphos-based palladium catalysts for the kinetic resolution of racemic cyclohexenyl acetate

High-throughput screening of the SUPRAphos library revealed a palladium catalyst based on supramolecular ligands that gave fast and highly efficient kinetic resolution of cyclohexenyl acetate with an S-value up to 12.

Islet-like cells differentiated from rat marrow mesenchymal stem cells

AIM: To explore the possibility of differentiating functional islet-like cells from marrow mesenchymal stem cells.

METHODS: Rat marrow mesenchymal stem cells (MSC) were isolated from Wistar rats and cultured. Passaged MSCs were induced to differentiate into islet-like cells under following condition: LN group, pre-induced with L-DMEM including 10 mmoL/LNicotinamide +1 mmoL/L mercapto-ethanol +20 mL/L fetal bovine serum for 24 h,then induced with serum free H-DMEM solution including 10 mmoL/L nicotinamide +1 mmoL/L mercaptoethanol for 10 h. HN group, pre-induced with L-DMEM including 20 mmoL/L Nicotinamide +20 mL/L fetal bovine serum for 24 h, then induced with serum free H-DMEM solution including 10 mmoL/L nicotinamide for 10 h. Differentiated cells were observed under inverse microscope, insulin and nestin expressed in differentiated cells were detected with immunocytochemistry. Diabetes model was induced with streptozotocin (STZ) injection, and 3 diabetes rats were subcutaneously injected with 1×10⁷ islet cells differentiated from MSC respectively, and blood glucose level was tested 1 wk after cell injection.

RESULTS: Islet -like clustered cells were observed under both LN and HN groups, abundant insulin expression was detected in islet-like cells, and nestin was detected in pre-differentiated cells. Glucose level in STZ-diabetic rats could be effectively controlled by islet cells differentiated from MSC.

CONCLUSION: Islet-like functional cells can be differentiated from marrow mesenchymal stem cells, which may be a new procedure for clinical treatment of diabetes.

Application of monodentate secondary phosphine oxides, a new class of chiral ligands, in Ir(i)-catalyzed asymmetric imine hydrogenation

Secondary phosphine oxides were prepared from R(1)PCl(2) and R(2)MgBr, followed by hydrolysis. They were obtained in an enantiopure form by preparative chiral HPLC. These new monodentate ligands were tested in the iridium-catalyzed hydrogenation of imines at 25 bar. Enantioselectivities up to 76% were obtained at L/Ir = 2. Addition of pyridine (Pyr/Ir = 1:2) raised the ee to 83%. Using pyridine as an additive allowed reduction of the L/Ir ratio to 1 without reduction of ee. [reaction: see text]

Changes in local cerebral blood flow, glucose utilization, and mitochondrial function following traumatic brain injury in rats

The pathophysiology of secondary brain damage following experimental traumatic brain injury was investigated by measuring local cerebral blood flow (lCBF), local cerebral glucose utilization (lCGU), and activity of succinate dehydrogenase (SDH), which is a mitochondrial enzyme of the tricarboxylic acid cycle, in the rat brain after moderate lateral fluid percussion injury. Measurements used autoradiography for lCBF and lCGU with [14C]iodoantipyrine and [14C]2-deoxyglucose, respectively. Regional SDH activity was determined using quantitative imaging of formazan produced from 2,3,5-triphenyl tetrazolium chloride by SDH. lCBF decreased at 1 hour after injury and was significantly lower than the preinjury level in almost all regions of both hemispheres at 6 and 24 hours, and remained low at 2 weeks. lCGU increased 1 hour after injury but was significantly decreased at 6 and 24 hours, and at 2 weeks in most regions of both hemispheres. The ipsilateral hemisphere showed a significant decrease in the activity of SDH in the cortices, hippocampus, thalamus, and caudate/putamen, most conspicuously 72 hours after injury, whereas no significant decrease was observed in the contralateral hemisphere at any time. Necrosis in the injured cortex and reduction of the number of neurons in the ipsilateral hippocampus were observed 2 weeks after injury. The present study showed that a decrease in lCBF and mitochondrial dysfunction occur with glucose hypermetabolism around 1 hour after lateral fluid percussion injury, and that lCBF, lCGU, and mitochondrial function all deteriorate after 6 hours. This suggests that lCBF and cellular metabolism may change dynamically during the several hours following traumatic brain injury, and afterwards neuronal damage may result in an irreversible change in the areas with depressed glucose hypermetabolism in the early period after injury in combination with mitochondrial dysfunction.

Local mitochondrial function following traumatic brain injury in rats

The effect of lateral fluid percussion injury on mitochondrial function in the rat brain was investigated by quantitative imaging of changes in the regional activity of succinate dehydrogenase (SDH), a mitochondrial enzyme of the tricarboxylic acid cycle for adenosine triphosphate production. Regional SDH was measured in the frontal, parietal, temporal, and occipital cortices, CA1 and CA2-3 of the hippocampus, thalamus, corpus callosum, caudate/putamen, and cerebellum 1 hour and 72 hours after low, medium, and high pressure injury. No regional difference between the hemispheres in the activity of SDH was observed in the sham group. The hippocampus showed high SDH activity. The CA2-3 regions showed the highest activity among the regions examined. The corpus callosum, which is white matter, showed the lowest. One hour after low pressure fluid percussion injury, only the frontal lobe showed significantly lower SDH activity than the sham control in the ipsilateral hemisphere, whereas after 72 hours SDH activity was significantly lower in the frontal, parietal, and temporal lobes. SDH activity was significantly lower in the frontal, parietal, and temporal lobes in the medium and high pressure injury groups than in the sham control 1 hour after injury, and SDH activity in the CA1 and CA2-3 of the hippocampus was significantly decreased 72 hours after injury. No decrease in SDH activity was observed in any region of the contralateral hemisphere either 1 hour or 72 hours after injury. Mitochondrial dysfunction of the ipsilateral cortex and hippocampus following fluid percussion injury is correlated with the severity of injury and advances with time after injury. The results suggest that progression of mitochondrial dysfunction is associated with secondary bioenergetic deterioration.