Single-nucleus Atlas of Sevoflurane-induced Hippocampal Cell Type- and Sex-specific Effects during Development in Mice.

BACKGROUND: Multiple neonatal exposures to sevoflurane induce neurocognitive dysfunctions in rodents. The lack of cell type-specific information after sevoflurane exposure limits the mechanistic understanding of these effects. In this study, the authors tested the hypothesis that sevoflurane exposures alter the atlas of hippocampal cell clusters and have neuronal and nonneuronal cell type-specific effects in mice of both sexes. METHODS: Neonatal mice were exposed to 3% sevoflurane for 2 h at postnatal days 6, 8, and 10 and analyzed for the exposure effects at postnatal day 37. Single-nucleus RNA sequencing was performed in the hippocampus followed by in situ hybridization to validate the results of RNA sequencing. The Morris Water Maze test was performed to test neurocognitive function. RESULTS: The authors found sex-specific distribution of hippocampal cell types in control mice alongside cell type- and sex-specific effects of sevoflurane exposure on distinct hippocampal cell populations. There were important changes in male but not in female mice after sevoflurane exposure regarding the proportions of cornu ammonis 1 neurons (control vs. sevoflurane, males: 79.9% vs. 32.3%; females: 27.3% vs. 24.3%), dentate gyrus (males: 4.2% vs. 23.4%; females: 36.2% vs. 35.8%), and oligodendrocytes (males: 0.6% vs. 6.9%; females: 5.9% vs. 7.8%). In male but not in female mice, sevoflurane altered the number of significantly enriched ligand-receptor pairs in the cornu ammonis 1, cornu ammonis 3, and dente gyrus trisynaptic circuit (control vs. sevoflurane, cornu ammonis 1-cornu ammonis 3: 18 vs. 42 in males and 15 vs. 21 in females; cornu ammonis 1-dentate gyrus: 21 vs. 35 in males and 12 vs. 20 in females; cornu ammonis 3-dentate gyrus: 25 vs. 45 in males and 17 vs. 20 in females), interfered with dentate gyrus granule cell neurogenesis, hampered microglia differentiation, and decreased cornu ammonis 1 pyramidal cell diversity. Oligodendrocyte differentiation was specifically altered in females with increased expressions of Mbp and Mag. In situ hybridization validated the increased expression of common differentially expressed genes. CONCLUSIONS: This single-nucleus RNA sequencing study reveals the hippocampal atlas of mice, providing a comprehensive resource for the neuronal and nonneuronal cell type- and sex-specific effects of sevoflurane during development.

G-Quadruplex DNA with an Apurinic Site as a Soft Molecularly Imprinted Sensing Platform.

Molecularly imprinted polymers (MIPs) provide versatile sensor platforms to recognize targets by shape complementarity. However, the rigid structure of the classic MIPs compromises the signal transduction with necessary polymer and target modifications. Herein, we tried to use a flexible DNA that has a perfectly structured folding as the soft molecularly imprinted polymer (SMIP) for a straightforward sensor. As a proof of concept, the guanosine SMIP recognition was achieved by removal of a guanosine from a G-quadruplex-forming sequence (G4). The G4 folding structure with such an apurinic site (AP site) provides a well-defined MIP binding accommodation for guanosine according to the shape complementarity. The guanosine binding at the AP site subsequently leads to a conformation change suitable for remote readout using a G4-specific fluorescent ligand. The G4 sequence and AP site position were optimized for this SMIP behavior. Due to the G4 compact structure and the remaining hydrogen bonding pattern, nucleosides other than guanosine and negatively charged nucleotides exhibit no binding with the AP site, suggesting a high selectivity in the SMIP recognition. The proposed rationale was then convinced by the alkaline phosphatase-catalyzed GMP hydrolysis. Our work will inspire more interest in exploring nucleic acids as the SMIP frameworks due to their variant conformations and well-established molecular engineering.

Late hematoma, seroma, and galactocele in breasts injected with polyacrylamide gel.

Late hematoma or seroma and galactocele caused by augmentation mammaplasty have been reported in patients with silicon breast prostheses but are extremely rare in patients injected with polyacrylamide gel (PAAG). In a retrospective survey, the incidence, clinical manifestations, and management of late hematoma, seroma, and galactocele in 28 of 2,610 patients who underwent breast augmentation with PAAG injection were investigated, and 5 typical cases are presented. The diagnostic and managing methods for this complication have been assessed. The incidence of late hematoma or seroma was 0.65% and that of galactocele was 0.35% among patients with PAAG-injected breast augmentations. The clinical onsets of such late PAAG complications were of two types: rapid enlargement in 17 patients and progressive expansion in another 11 patients. Aspiration, ultrasound, and magnetic resonance imaging (MRI) are useful and sensitive tools for diagnosis. Foreign body reaction, PAAG-related tissue necrosis and fibrosis, and granuloma were shown, and the bacterial cultures in all 12 cases were negative. Needle aspiration with pressure dressing has been advocated as a reliable method for small diseases, and surgical exploration with irrigation-vacuum drainage and evacuation with capsulectomy have been considered more effective for recurrent, large, and long-term cases. In conclusion, these late complications rarely present after large-volume injections of PAAG for breast augmentation. The PAAG-related pathologic inflammatory tissue changes are suggested as the pathogenesis for the complication. Trauma and breastfeeding are considered to be stimulating factors.

Novel Fe3O4@metal-organic framework@polymer core-shell-shell nanospheres for fast extraction and specific preconcentration of nine organophosphorus pesticides from complex matrices.

Herein, a novel core-shell-shell magnetic nanosphere denoted as Fe3O4@ZIF-8@polymer was fabricated by sequential in situ self-assembly and precipitation polymerization for effective magnetic solid-phase extraction of nine organophosphorus pesticides (OPPs) from river water, pear, and cabbage samples. The integrated Fe3O4@ZIF-8@polymer featured convenient magnetic separation property and excellent multi-target binding ability. More importantly, the functional polymer coating greatly improved the extraction performance of Fe3O4@ZIF-8 for OPPs, thus facilitating the simultaneous determination of trace OPP residues in real samples. The developed MPSE-LC-MS/MS method exhibited good linearity (R2 ≥ 0.9991) over the concentration range of 0.2-200 µg L-1, low limits of detection of 0.0002-0.005 µg L-1 for river water and 0.006-0.185 µg kg-1 for pear and cabbage, satisfactory precision with relative standard deviations ≤ 9.7% and accuracy with recoveries of 69.5-94.3%. These results highlight that the combination of polymers with MOFs has great potential to fabricate excellent adsorbents for high-throughput analysis of various contaminants in complex matrices.

Multifunctional Liposomes Enable Active Targeting and Twinfilin 1 Silencing to Reverse Paclitaxel Resistance in Brain Metastatic Breast Cancer.

Paclitaxel (PTX) is a first-line chemotherapeutic drug for breast cancer, but PTX resistance often occurs in metastatic breast cancer. In addition, due to the poor targeting of chemotherapeutic drugs and the presence of the blood-brain barrier (BBB), it is hard to effectively treat brain metastatic breast cancer using paclitaxel. Thus, it is urgent to develop an effective drug delivery system for the treatment of brain metastatic breast cancer. The current study found that TWF1 gene, an epithelial-mesenchymal transition-associated gene, was overexpressed in brain metastatic breast cancer (231-BR) cells and was associated with the PTX resistance of 231-BR cells. Knockdown of TWF1 by small interference RNA (siRNA) in 231-BR cells could effectively increase the sensitivity of brain metastatic breast cancer cells to paclitaxel. Then, a liposome-based drug delivery system was developed for PTX delivery across BBB, enhancing PTX sensitivity and brain metastases targeting via BRBP1 peptide modification. The results showed that BRBP1-modified liposomes could effectively cross the BBB, specifically accumulate in brain metastases, and effectively interfere TWF1 gene expression in vitro and in vivo, and thus they enhanced proliferation inhibition, cell cycle arrest, and apoptosis induction, thereby inhibiting the formation and growth of brain metastases. In summary, our results indicated that BRBP1-modified and PTX- and TWF1 siRNA-loaded liposomes have the potential for the treatment of brain metastatic breast cancer, which lays the foundation for the development of a new targeted drug delivery system.

Long-term Pulpal and Restorative Outcomes of Pulpotomy in Mature Permanent Teeth.

INTRODUCTION: Pulpotomy in mature permanent cariously exposed teeth preserves the remaining pulp tissues, but long-term outcomes of the pulp and the restoration are unknown. This prospective study examined the immediate and long-term status of the pulp and the restored tooth and identified potential predictors of early and late failures in teeth that were asymptomatic or experiencing only mild symptoms at the time of treatment. METHODS: Pulpotomy was performed using the aseptic technique and a tricalcium silicate cement under local anesthesia. Teeth were assessed for up to 5 years for pulpal and apical signs and symptoms, restorative marginal integrity, and periodontal health. RESULTS: Fifty-two patients (61 teeth) with a median age of 40 years (range, 21-75 years) were included in this study; 17 (32.7%) men and 35 (67.3%) women were treated and reviewed. Overall pulp survival was 90.2% (95% confidence interval, 79.8%-96.3%); 6 teeth developed irreversible pulpitis or pulp necrosis when the restoration was intact. Preoperative pain was a potential predictor (P < .05) for early failure. Eleven late failures occurred between 2 and 4 years: 1 tooth with intact coronal restoration had pulp necrosis and asymptomatic apical periodontitis, 4 had recurrent caries resulting in asymptomatic apical periodontitis, 4 remained vital and only needed new restorations, 1 was unrestorable, and 1 was extracted for periodontal reasons. The type of definitive restoration was a potential predictor for late failure (P < .05). CONCLUSIONS: Carious pulp exposures in asymptomatic mature permanent teeth can be predictably managed by pulpotomy using a tricalcium silicate cement. Short-term failures were few and managed by pulpectomy. Appropriate coronal restoration is critical to long-term success.

[Limited external fixation of plastic cardboard for the treatment of senile comminuted humeral fracture].

OBJECTIVE: To explore clinical efficacy of limited external fixation with plastic paperboard in treating senile proximal comminuted humeral fracture. METHODS: From June 2015 to December 2017, 32 senile patients with proximal comminuted fracture of humerus were treated with plasticized cardboard after manual external fixation. Among them, including 13 males and 19 females aged from 55 to 85 years old with an average of(68.22±8.36) years old; 18 patients on the left side and 14 patients on the right side; all patients were regularly review shoulder X-rays and performed appropriate functional exercises. Constant-Murley shoulder joint scoring was used to evaluate clinical effects. RESULTS: Thirty-two patients were followed up for 3 to 12 months with an average of (4.97±2.39) months. All patients were underwent functional exercise under guidance of physicians. Nine patients were treated with topical Chinese herbal moist heat compresses to promote shoulder function recovery. Thirty-one patients were obtained fracture healing, the time ranged from 5 to 12 weeks with an average of(7.44±1.72)weeks. One patient was not healed due to comminuted fracture of fracture end and the separation was large, the blood supply to humeral head was insufficient for necrosis absorption. Postoperative Constant-Murley shoulder score at 3 months was 87.56±6.93; 15 patients got excellent results, 14 good, 2 fair and 1 poor. CONCLUSIONS: Limited external fixation with plastic paperboard for the treatment of senile proximal comminuted humeral fracture could ensure biomechanical stability of fracture, promote early recovery of shoulder joint function and shorten recovery time.

Highly sensitive and selective sensor for sunset yellow based on molecularly imprinted polydopamine-coated multi-walled carbon nanotubes.

Polydopamine (PDA) can be formed by monomeric self-polymerization in water. This convenient behavior was exploited to prepare a molecularly imprinted polymer (MIP) layer on the surface of multi-walled carbon nanotubes (MWCNTs) with sunset yellow (SY) as a template molecule. The prepared nanocomposites were characterized, and their electrochemical behavior towards SY was investigated. Under the optimized conditions, a glassy carbon electrode modified with the imprinted nanocomposite showed a highly selective and ultrasensitive electrochemical response to SY compared with the performance of control electrodes and previously reported electrochemical sensors for SY. The improved behavior of the developed sensor can be attributed to its superficial highly matched imprinted cavities on the excellent electrocatalytic matrix of MWCNTs and the electronic barrier of the non-imprinted PDA to outside molecules. The fabricated sensor expressed a linear relationship to SY concentrations from 2.2nM to 4.64µM with a detection limit of 1.4nM (S/N = 3). The sensor also exhibited excellent selectivity for SY over its structural analogs, good stability, and adequate reproducibility. The prepared sensor was successfully used to detect SY in real spiked samples. This methodology has potential application value and may be readily adapted to design other PDA-based MIP sensors.

Oligomeric structure of the ATP-dependent protease La (Lon) of Escherichia coli.

Lon, also known as protease La, belongs to a class of ATP-dependent serine protease. It plays an essential role in degradation of abnormal proteins and of certain short-lived regulatory proteins, and is thought to possess a Ser-Lys catalytic dyad. To examine the structural organization of Lon, we performed an electron microscope analysis. The averaged images of Lon with end-on orientation revealed a six-membered, ring-shaped structure with a central cavity. The side-on view showed a two-layered structure with an equal distribution of mass across the equatorial plane of the complex. Since a Lon subunit possesses two large regions containing nucleotide binding and proteolytic domains, each layer of the Lon hexamer appears to consist of the side projections of one of the major domains arranged in a ring. Lon showed a strong tendency to form hexamers in the presence of Mg(2+), but dissociated into monomers and/or dimers in its absence. Moreover, Mg(2+)-dependent hexamer formation was independent of ATP. These results indicate that Lon has a hexameric ring-shaped structure with a central cavity, and that the establishment of this configuration requires Mg(2+), but not ATP.

Conducting polymer polypyrrole supported bilayer lipid membranes.

Electrochemically synthesized conducting polymer polypyrrole (PPy) film on gold electrode surface was used as a novel support for bilayer lipid membranes (BLMs). Investigations by surface plasmon resonance (SPR) suggest that dimyristoyl-L-alpha-phosphatidylcholine (DMPC) and dimyristoyl-L-alpha-phosphatidyl-L-serine (DMPS) can form BLMs on PPy film surface but dimyristoyl-L-alpha-phosphatidylglycerol (DMPG) and didodecyldimethylammonium bromide (DDAB) can not do so, indicating the formation of PPy supported bilayer lipid membranes (s-BLMs) is dependent on the chemical structure of the lipids used. The self-assembly of DMPC induces a smoother topography than the PPy layer with rms roughness decreasing from 4.484 to 2.914 nm convinced by atomic force microscopy (AFM). Impedance spectroscopy measurements confirm that the deposition of BLM substantially increases the resistance of the system indicating a very densely packed BLM structures. The little change of PPy film in capacitance shows that solvent and electrolyte ions still retain within the porous PPy film after BLM deposition. Therefore, the PPy supported BLM is to some extent comparable to conventional BLM with aqueous medium retaining at its two sides. As an example and preliminary application, horseradish peroxidase (HRP) reconstituted into the s-BLM shows the expected protein activity and can transfer electron from or to the underlying PPy support for its response to electrocatalytic reduction of hydrogen peroxide in solution. Thus the system maybe possesses potential applications to biomimetic membrane studies.

[Clinical study of immediate implant].

OBJECTIVE: To evaluate the clinical result of immediate implant. METHODS: 32 cases underwent immediate implant surgery for 59 implants simultaneously when the teeth or roots extracted. 55 implants were placed with bone grafts or bone substitutes. The second stage operation were performed in the sixth month and ceramic crown were fixed in the seventh to eighth month postoperatively, the follow up were mean 39 months. RESULTS: One implant was lost. Bone resorption of alveolar crest was observed in 4 implants. Mean resorption was 2 mm. CONCLUSIONS: The result of immediate implant is predictable, the advantages are avoiding the alveolar bone resorption after teeth extraction, implant could be placed in an ideal position; less operation trauma, good esthetics results.