Ultrabroad bandwidth of quasi-parametric amplification beyond the phase-matching limit.

Quasi-parametric amplification (QPA), a variant of optical parametric amplification, can release the phase-matching requirement owing to the introduction of idler dissipation, and thus may support ultrabroad bandwidth. Here we establish the gain-dispersion equation for QPA, which reveals the interplay of signal gain, idler dissipation and phase mismatch. The idler dissipation dramatically enhances the gain bandwidth, which breaks the limit set by phase matching. We theoretically demonstrate that QPA with strong dissipation allows high-efficiency few-cycle pulse amplification in those nonlinear crystals without a magic phase-matching solution.

Te-doped-WSe2/W as a stable monolith catalyst for ampere-level current density hydrogen evolution reaction.

The development of efficient electrocatalysts for the hydrogen evolution reaction (HER) holds immense importance in the context of large-scale hydrogen production from water. Nevertheless, the practical application of such catalysts still relies on precious platinum-based materials. There is a pressing need to design high-performing, non-precious metal electrocatalysts capable of generating hydrogen at substantial current levels. We report here a stable monolith catalyst of Te-doped-WSe2 directly supported by a highly conductive W mesh. This catalyst demonstrates outstanding electrocatalytic performance and stability in acidic electrolytes, especially under high current conditions, surpassing the capabilities of commercial 5% Pt/C catalysts. Specifically, at current densities of 10 and 1200 mA cm-2, it exhibits a minimal overpotential of 79 and 232 mV, along with a small Tafel slope of 55 mV dec-1, respectively. The remarkable catalytic activity of Te-WSe2 can be attributed to the exceptional electron transfer facilitated by the stable monolithic structure, as well as the abundant and efficient active sites in the material. In addition, density functional theory calculations further indicate that Te doping adjusts H atom adsorption on various positions of WSe2, making it closer to thermal neutrality compared to the original material. This study presents an innovative approach to develop cost-effective HER electrocatalysts that perform optimally under high current density conditions.

Modified double-pulley fixation provides better reduction of bone fragments and union compared to single-point fixation in bony Bankart lesions.

PURPOSE: The purpose of this study was to compare clinical scores and imaging outcomes of bony Bankart lesions that underwent single-point and modified double-pulley fixation after at least 2 years of follow-up. METHODS: Patients who underwent surgery to treat bony Bankart injuries were included and divided into groups A and B. A total of 69 patients were included (32 in group A and 37 in group B). Patients in group A underwent arthroscopic modified double-pulley fixation and patients in group B underwent arthroscopic single-point fixation. Three-dimensional computed tomography (3D-CT) was used to assess glenoid reduction one day after surgery. Postoperative bony union was assessed using 3D-CT and multiplanar reconstruction images 6 months after surgery. Constant-Murley, Rowe rating system, visual analogue scale and University of California at Los Angeles and American Shoulder and Elbow Surgeons scores were recorded before and after surgery. RESULTS: In terms of imaging measurements, there was no significant group difference in the preoperative size of the glenoid defect, the size of the bony fragment or the expected postoperative size of the glenoid defect. The sizes of the actual postoperative glenoid defects differed significantly between the groups (p = 0.027), as did the absolute difference between the expected and actual glenoid defect sizes (p < 0.001). At 6 months postoperatively, 50.0% of group A patients and 24.3% of group B patients exhibited complete bony union (p = 0.027); the rates of partial union were 37.5% and 56.8%, respectively. At the final follow-up, all clinical scores were significantly better than the preoperative scores (all p < 0.05), with no significant group differences (not significant). CONCLUSIONS: The use of the modified double-pulley technique with two anchors to treat bony Bankart injuries provides a better reduction of bone fragments than single-point fixation with two anchors and was associated with a higher rate of early bone union. LEVEL OF EVIDENCE: Level III.

Generation of an ultrashort pulse train through ultrafast parity-time symmetry switching.

We propose a scheme for the direct generation of an ultrashort pulse train as well as the further compression of pulsed lasers based on the nonlinearity inherent to parity-time (PT) symmetric optical systems. Implementation of optical parametric amplification in a directional coupler of χ(2) waveguides enables ultrafast gain switching through pump-controlled breaking of PT symmetry. We theoretically demonstrate that pumping such a PT symmetric optical system with a periodically amplitude-modulated laser enables periodic gain switching, which can directly convert a continuous-wave signal laser into a train of ultrashort pulses. We further demonstrate that by engineering the PT symmetry threshold, an apodized gain switching that enables the production of ultrashort pulses without side lobes. This work suggests a new approach for exploring the non-linearity inherent to various PT symmetric optical structures to extend optical manipulation capabilities.

Sub-picosecond tunable mid-infrared light source for driving high-efficiency optical rectification.

Optical rectification (OR) is a popular way to generate coherent terahertz radiation. Here, we develop a sub-picosecond mid-infrared (mid-IR) light source with a tailored wavelength and pulse duration for enhancing the OR efficiency. Numerical simulations for a LiNbO3-based OR with tilted pulse-front excitation are first conducted to determine the optimal parameters of pump wavelength and pulse duration, demonstrating that the OR efficiency pumped by 4-µm sub-picosecond (0.5-0.6 ps) pulses is approximately twice the value with 0.8-µm pump at the same conditions. Guided by the simulation results, we build a BaGa4Se7-based optical parametric chirped-pulse amplification system with 1030-nm thin-disk pump and broadband mid-IR seeds. The output performances of >200-µJ pulse energy, ∼600-fs pulse duration and 1-kHz pulse repetition rate are achieved in a spectral range tunable from 3.5 to 5 µm. The large energy scalability and high parameter tunability make the light source attractive to high-efficiency OR in various materials.

Lycopene abolishes typical polyhalogenated carbazoles (PHCZs)-induced hepatic injury in yellow catfish (Pelteobagrus fulvidraco): Involvement of ROS/PI3K-AKT/NF-κB signaling.

Aquatic ecosystems are being more contaminated with polyhalogenated carbazoles (PHCZs), which raising concerns about their impact on aquatic organisms. Lycopene (LYC) exhibits several beneficial properties for fish via enhance antioxidant defenses and improve immunity. In this study, we attempted to investigate the hepatotoxic effects of typical PHCZs 3, 6-dichlorocarbazole (3,6-DCCZ) and the protective mechanisms of LYC. In this study, we found that yellow catfish (Pelteobagrus fulvidraco) exposure to 3,6-DCCZ (1.2 mg/L) resulted in hepatic inflammatory infiltration and disordered hepatocyte arrangement. Besides, we observed that 3,6-DCCZ exposure resulted in hepatic reactive oxygen species (ROS) overproduction and excessive autophagosome accumulation, accompanied with inhibition of phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) pathway. Subsequently, we confirmed that 3,6-DCCZ exposure triggered hepatic uncontrolled inflammatory response via activation of nuclear factor-κB (NF-κB) pathway, along with decreased plasma complement C3 (C3) and complement C4 (C4) levels. Meanwhile, yellow catfish exposed to 3,6-DCCZ exhibit an increased hepatic apoptosis phenomenon, as evidenced by the elevated number of positive TUNEL cells and upregulated expression of caspase3 and cytochrome C (CytC). In contrast, LYC treatment could alleviate the 3,6-DCCZ-induced pathological changes, hepatic ROS accumulation, autophagy, inflammatory response and apoptosis. To sum up, this study provided the demonstration that LYC exerts hepatoprotective effects to alleviate 3,6-DCCZ-induced liver damage by inihibiting ROS/PI3K-AKT/NF-κB signaling in yellow catfish.

Natural epidithiodiketopiperazine alkaloids as potential anticancer agents: Recent mechanisms of action, structural modification, and synthetic strategies.

Cancer has become a grave health crisis that threatens the lives of millions of people worldwide. Because of the drawbacks of the available anticancer drugs, the development of novel and efficient anticancer agents should be encouraged. Epidithiodiketopiperazine (ETP) alkaloids with a 2,5-diketopiperazine (DKP) ring equipped with transannular disulfide or polysulfide bridges or S-methyl moieties constitute a special subclass of fungal natural products. Owing to their privileged sulfur units and intriguing architectural structures, ETP alkaloids exhibit excellent anticancer activities by regulating multiple cancer proteins/signaling pathways, including HIF-1, NF-κB, NOTCH, Wnt, and PI3K/AKT/mTOR, or by inducing cell-cycle arrest, apoptosis, and autophagy. Furthermore, a series of ETP alkaloid derivatives obtained via structural modification showed more potent anticancer activity than natural ETP alkaloids. To solve supply difficulties from natural resources, the total synthetic routes for several ETP alkaloids have been designed. In this review, we summarized several ETP alkaloids with anticancer properties with particular emphasis on their underlying mechanisms of action, structural modifications, and synthetic strategies, which will offer guidance to design and innovate potential anticancer drugs.

Recent progress in chemistry and bioactivity of monoterpenoid indole alkaloids from the genus gelsemium: a comprehensive review.

Monoterpenoid indole alkaloids (MIAs) represent a major class of active ingredients from the plants of the genus Gelsemium. Gelsemium MIAs with diverse chemical structures can be divided into six categories: gelsedine-, gelsemine-, humantenine-, koumine-, sarpagine- and yohimbane-type. Additionally, gelsemium MIAs exert a wide range of bioactivities, including anti-tumour, immunosuppression, anti-anxiety, analgesia, and so on. Owing to their fascinating structures and potent pharmaceutical properties, these gelsemium MIAs arouse significant organic chemists' interest to design state-of-the-art synthetic strategies for their total synthesis. In this review, we comprehensively summarised recently reported novel gelsemium MIAs, potential pharmacological activities of some active molecules, and total synthetic strategies covering the period from 2013 to 2022. It is expected that this study may open the window to timely illuminate and guide further study and development of gelsemium MIAs and their derivatives in clinical practice.

Ferroptosis contribute to neonicotinoid imidacloprid-evoked pyroptosis by activating the HMGB1-RAGE/TLR4-NF-κB signaling pathway.

Imidacloprid (IMI) is among the common neonicotinoid insecticides used in agriculture worldwide, posing a potential toxic threat to non-target animals and humans. Numerous studies have shown that ferroptosis is involved in the pathophysiological progression of renal diseases. However, it remains unclear whether ferroptosis is involved in IMI-induced nephrotoxicity. In the present study, we investigated the potential pathogenic role of ferroptosis in IMI-induced kidney damage in vivo. Transmission electron microscopy (TEM) showed that the mitochondrial crest of kidney cells significantly decreased following IMI exposure. Moreover, IMI exposure triggered ferroptosis and lipid peroxidation in the kidney. We confirmed that nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated antioxidant capability was negatively correlated with the ferroptosis induced by IMI exposure. Importantly, we verified that NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3)-driven inflammation occurred in the kidneys following IMI exposure, but pretreatment with the ferroptosis inhibitor ferrostatin (Fer-1) blocked this phenomenon. Additionally, IMI exposure induced F4/80+ macrophages to accumulated in the proximal tubules of the kidneys, and also increased the protein expression of high-mobility group box 1 (HMGB1), receptor for advanced glycation end products (RAGE), receptor for advanced glycation end products (TLR4), and nuclear factor kappa-B (NF-κB). In contrast, inhibition of ferroptosis by Fer-1 blocked IMI-induced NLRP3 inflammasome activation, F4/80 positive macrophages, and the HMGB1-RAGE/TLR4 signaling pathway. To the best of our knowledge, this is the first study to reveal that IMI stress can induce Nrf2 inactivation, thereby triggering ferroptosis, causing an initial wave of death, and activating HMGB1-RAGE/TLR4 signaling, which promotes pyroptosis that perpetuates kidney dysfunction.

Molecular genetic mechanisms of teratozoospermia.

In recent years, the incidence of teratospermia has been increasing, and it has become a very important factor leading to male infertility. The research on the molecular mechanism of teratospermia is also progressing rapidly. This article briefly summarizes the clinical incidence of teratozoospermia, and makes a retrospective summary of related studies reported in recent years. Specifically discussing the relationship between gene status and spermatozoa, the review aims to provide the basis for the genetic diagnosis and gene therapy of teratozoospermia.

Safe femoral tunnel drilling angles avoid injury to the medial and posteromedial femoral anatomic structures during single-bundle posterior cruciate ligament reconstruction with the inside-out technique.

PURPOSE: To investigate the relationship between the medial and posteromedial femoral anatomic structures and the femoral tunnel exit produced by different tunnel orientations when creating the femoral tunnel for posterior cruciate ligament reconstruction (PCLR) using the inside-out (IO) technique and to estimate safe tunnel orientations to minimize the risk of iatrogenic injury to these structures. METHODS: Eleven cadaveric knees were used. The medial and posteromedial aspects of each knee joint were dissected to reveal the "safe zone," which is a bony area that avoids the distribution or attachment of at-risk structures (MCL, PMC structures, and articular cartilage), while remaining 10 mm away from the articular cartilage. The hypothesis of this study was that by creating the femoral tunnel at specific angles using the IO technique, the tunnel outlet would be as close to the safe zone as possible, protecting the at-risk structures from damage. Femoral tunnels were drilled at 20 different angle combinations on each specimen: 0°, 15°, 30°, 45°, and 60° relative to a line parallel to the transepicondylar axis in the axial plane, as well as 15°, 30°, 45°, and 60° relative to a line parallel to the femoral axis in the coronal plane. The positional relationship between each tunnel exit and the safe zone was recorded, and the shortest distance between the exit center and the safe zone boundary was measured. RESULTS: The risk of iatrogenic injury differed depending on the drilling orientation (χ2 = 168.880, P < 0.001). Femoral drilling angle combinations of 45/45°, 45/60°, 60/30°, 60/45°, and 60/60° (axial/coronal) were considered relatively safer than other orientations (P < 0.05). The shortest distance between the tunnel exit and the safe zone boundary was negatively correlated with the angle in the axial plane (P < 0.001, r = - 0.810). CONCLUSIONS: When creating the IO femoral tunnel for single-bundle PCL reconstruction, angle combinations of 45/45°, 45/60°, 60/30°, 60/45°, and 60/60° (axial/oblique coronal) could be utilized to prevent at-risk structures from being damaged. The drilling angles and the safe zone can be employed to optimize the femoral tunnel in PCLR.

Single and Combined Effects of Chlorpyrifos and Glyphosate on the Brain of Common Carp: Based on Biochemical and Molecular Perspective.

Chlorpyrifos (CPF) and glyphosate (GLY) are the most widely used organophosphate insecticide and herbicide worldwide, respectively; co-occurrence of CPF and GLY in aquatic environments occurs where they inevitably have potential hazards to fish. However, the potential mechanisms of CPF and GLY to induce toxicity have not been fully explored. To identify the adverse impacts of CPF and GLY on fish, either alone or in combination (MIX), CPF (25 µg/L) and GLY (3.5 mg/L) were set up according to an environmentally relevant concentration to expose to common carp for 21 days. After exposure, CPF and GLY decreased the activities of acetylcholinesterase and Na+/K+-ATPase, altered monoamine oxidase levels, decreased antioxidant enzyme activities (superoxide dismutase, catalase, glutathione S-transferase and glutamic reductase), and induced the accumulation of malondialdehyde in the carp brain. The parameters in the MIX groups had a greater impact compared to that in the CPF or GLY group, suggesting that both single and combined exposure could affect neurological signaling systems and cause oxidative stress and lipid peroxidation damage in carp brains, and that MIX exposure increases the impact of each pollutant. RNA-seq results showed that single or combined exposure to CPF and GLY induced global transcriptomic changes in fish brains, and the number of differentially expressed genes in MIX-treated carp brains were globally increased compared to either the CPF or GLY groups, suggesting that the effects of co-exposure were greater than single exposure. Further analysis results revealed that the global transcriptomic changes participated in oxidative stress, immune dysfunction, and apoptosis of fish brains, and identified that the P13k-Akt signaling pathway participates in both single and combined exposure of CPF- and GLY-induced toxicity. Taken together, our results demonstrated that the interaction of CPF and GLY might be synergic and provided novel insights into the molecular mechanisms of fish brains coping with CPF and GLY.

Human Endogenous Retrovirus, SARS-CoV-2, and HIV Promote PAH via Inflammation and Growth Stimulation.

Pulmonary arterial hypertension (PAH) is a pulmonary vascular disease characterized by the progressive elevation of pulmonary arterial pressures. It is becoming increasingly apparent that inflammation contributes to the pathogenesis and progression of PAH. Several viruses are known to cause PAH, such as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), human endogenous retrovirus K(HERV-K), and human immunodeficiency virus (HIV), in part due to acute and chronic inflammation. In this review, we discuss the connections between HERV-K, HIV, SARS-CoV-2, and PAH, to stimulate research regarding new therapeutic options and provide new targets for the treatment of the disease.

Parameter sensitivities in tilted-pulse-front based terahertz setups and their implications for high-energy terahertz source design and optimization.

Despite the popularity and ubiquity of the tilted-pulse-front technique for single-cycle terahertz (THz) pulse generation, there is a deficit of experimental studies comprehensively mapping out the dependence of the performance on key setup parameters. The most critical parameters include the pulse-front tilt, the effective length of the pump pulse propagation within the crystal as well as effective length over which the THz beam interacts with the pump before it spatially walks off. Therefore, we investigate the impact of these parameters on the conversion efficiency and the shape of the THz beam via systematically scanning the 5D parameter space spanned by pump fluence, pulse-front-tilt, crystal-position (2D), and the pump size experimentally. We verify predictions so far only made by theory regarding the optimum interaction lengths and map out the impact of cascading on the THz radiation generation process. Furthermore, distortions imposed on the spatial THz beam profile for larger than optimum interaction lengths are observed. Finally, we identify the most sensitive parameters and, based on our findings, propose a robust optimization strategy for tilted-pulse-front THz setups. These findings are relevant for all THz strong-field applications in high demand of robust high-energy table-top single-cycle THz sources such as THz plasmonics, high-harmonic generation in solids as well as novel particle accelerators and beam manipulators.

Efficient generation of mid-infrared few-cycle pulses by the intrapulse difference-frequency generation in YCOB.

Yttrium calcium oxyborate (YCOB) crystals have been widely applied for generating intense near-infrared laser pulses by optical parametric amplification. Here, we show that the YCOB crystals oriented in both the XZ and XY principal planes possess broadband phase-matching property of intrapulse difference-frequency generation in the mid-infrared region. Few-cycle pulses tunable from 2 to 4 µm are experimentally produced by using a 7.5-fs pump laser at 800 nm, in which the conversion efficiency can be as high as 2.5%. With a large-size crystal and high-power pump laser, intrapulse difference-frequency generation based on YCOB may provide a new route for directly producing intense few-cycle mid-infrared pulses.

Piezo2 channel in nodose ganglia neurons is essential in controlling hypertension in a pathway regulated directly by Nedd4-2.

Baroreflex plays a crucial role in regulation of arterial blood pressure (BP). Recently, Piezo1 and Piezo2, the mechanically-activated (MA) ion channels, have been identified as baroreceptors. However, the underlying molecular mechanism for regulating these baroreceptors in hypertension remains unknown. In this study, we used spontaneously hypertensive rats (SHR) and NG-Nitro-l-Arginine (L-NNA)- and Angiotensin II (Ang II)-induced hypertensive model rats to determine the role and mechanism of Piezo1 and Piezo2 in hypertension. We found that Piezo2 was dominantly expressed in baroreceptor nodose ganglia (NG) neurons and aortic nerve endings in Wistar-Kyoto (WKY) rats. The expression of Piezo2 not Piezo1 was significantly downregulated in these regions in SHR and hypertensive model rats. Electrophysiological results showed that the rapidly adapting mechanically-activated (RA-MA) currents and the responsive neuron numbers were significantly reduced in baroreceptor NG neurons in SHR. In WKY rats, the arterial BP was elevated by knocking down the expression of Piezo2 or inhibiting MA channel activity by GsMTx4 in NG. Knockdown of Piezo2 in NG also attenuated the baroreflex and increased serum norepinephrine (NE) concentration in WKY rats. Co-immunoprecipitation experiment suggested that Piezo2 interacted with Neural precursor cell-expressed developmentally downregulated gene 4 type 2 (Nedd4-2, also known as Nedd4L); Electrophysiological results showed that Nedd4-2 inhibited Piezo2 MA currents in co-expressed HEK293T cells. Additionally, Nedd4-2 was upregulated in NG baroreceptor neurons in SHR. Collectively, our results demonstrate that Piezo2 not Piezo1 may act as baroreceptor to regulate arterial BP in rats. Nedd4-2 induced downregulation of Piezo2 in baroreceptor NG neurons leads to hypertension in rats. Our findings provide a novel insight into the molecular mechanism for the regulation of baroreceptor Piezo2 and its critical role in the pathogenesis of hypertension.

Effects of Temperature and Volume of Intraoperative Normal Saline Irrigation on Postoperative Pain, Swelling, and Serum Markers of Inflammation in Patients After Elective, Arthroscopic, Single-Bundle Surgical Reconstruction of the Anterior Cruciate Ligament: A Retrospective, Single-Center Study.

BACKGROUND Arthroscopic single-bundle surgical reconstruction of the anterior cruciate ligament (ACL) is often performed electively after 3 weeks of mobilization therapy. The present single-center retrospective study aimed to investigate the effects of temperature and volume of intraoperative normal saline irrigation on postoperative pain and swelling and on serum markers of inflammation following elective, arthroscopic, single-bundle surgical reconstruction of the ACL. MATERIAL AND METHODS Clinical data from 716 patients with non-acute ACL injuries who met the criteria between March 2015 and May 2020 were retrospectively analyzed. The patients were broken into 5 groups, depending on the volume or temperature of intraoperative irrigation with normal saline. At specific times after surgery, pain, knee swelling, and skin temperature were assessed. Postoperative levels of serum C-reactive protein (CRP), interleukin (IL)-1, IL-6, and IL-10 also were measured. RESULTS Visual analog scale (VAS) scores for pain, rates of swelling, and skin temperature differed significantly among the 5 groups at all postoperative time points (P<0.001). The VAS scores(P=0.322) and ratings for swelling (P=0.245), and skin temperature (P=0.093) were not significantly different among the volume groups. There were no significant differences in the VAS scores (P=0.055), swelling ratings (P=0.570), or skin temperatures (P=0.321) among the groups that received irrigation with normal saline at different temperatures. There were no significant differences in postoperative serum levels of CRP, IL-1, IL-6, or IL-10 among the groups (P>0.05). CONCLUSIONS Irrigation with different volumes and temperatures of normal saline did not have a significant effect on postoperative pain, swelling, or serum markers of inflammation.

Comparison of clinical outcome of decompression of suprascapular nerve at spinoglenoid notch for patients with posterosuperior massive rotator cuff tears and suprascapular neuropathy.

PURPOSE: In the present study, we aimed to determine whether decompression of suprascapular nerve (SSN) at the spinoglenoid notch could lead to a better functional outcome for the patients who underwent repairment of rotator cuff due to posterosupeior massive rotator cuff tear (MRCT) and suprascapular neuropathy. METHODS: A total of 20 patients with posterosuperior MRCT and suprascapular neuropathy were analyzed in the present work. The preoperative magnetic resonance imaging (MRI) showed rotator cuff tear in supraspinatus and infraspinatus. All patients underwent arthroscopic rotator cuff repair. Patients were divided into two groups (group A: non-releasing, group B: releasing) according to whether the SSN at the spinoglenoid notch was decompressed. The modified University of California at Los Angeles shoulder rating scale (UCLA) and visual analog scale (VAS) questionnaire were adopted to assess the function of the affected shoulder preoperatively and 12 months after the operation. Electromyography (EMG) and nerve conduction study (NCS) were used to evaluate the nerve condition. Patients underwent MRI and EMG/NCS at 6 months after operation and last follow-up. RESULTS: All patients were satisfied with the treatment. MRI showed that it was well-healed in 19 patients at 6 months after the operation. However, the fatty infiltration of supraspinatus and infraspinatus was not reversed. Only one patient in the non-releasing group showed the retear. The retear rate of group A and group B were 30% (3/10) and 20% (2/10) respectively at 12 months after the operation. One patient undergoing SSN decompression complained of discomfort in the infraspinatus area. His follow-up EMG after 6 months showed fibrillation potentials (1+) and positive sharp waves (1+) in the infraspinatus. The other patients' EMG results showed no abnormality. The postoperative UCLA and VAS scores were improved in both groups, and there was no significant difference in the follow-up outcomes between the two groups. CONCLUSIONS: Patients with postersuperior MRCT and suprascapular neuropathy, decompression of suprascapular nerve at spinoglenoid notch didn't lead to a better functional outcome with the repairment of rotator cuff. Arthroscopic rotator cuff repair could reverse the suprascapular neuropathy. LEVEL OF EVIDENCE: Level III.

Bilateral single-staged arthroscopic rotator cuff repair is comparable to staged procedures: a retrospective follow up study of 2 years.

BACKGROUND: Bilateral rotator cuff tears are not uncommon and the timing of the surgical treatment of both shoulders is debated. In the present study, we aimed to compare the clinical outcomes of patients who underwent single-stage or staged bilateral arthroscopic rotator cuff repair. METHODS: From March 2013 to May 2018, a retrospective review on all patients who underwent bilateral arthroscopic rotator cuff repair at our department was performed. Patients were separated into 2 groups: single-stage and staged. The minimum follow-up period was 2 years. The visual analog scale (VAS), American Shoulder and Elbow Surgeons (ASES) score, University of California, Los Angeles (UCLA) score, Constant-Murley (Constant) score, the range of motion (ROM) of the shoulder and the hospitalization costs were evaluated for comparison between the two groups before and after the operation. Differences between groups were assessed using t-tests and ANOVA. RESULTS: All 51 patients completed follow-up of 2 years, single stage (n = 24) and staged group (n = 27). There was no significant difference in the VAS, ASES, UCLA and Constant scores between the single-stage group and the staged group before the operation. Postoperative clinical scores were significantly improved in both groups (P < 0.05). All outcome scores were significantly different between the two groups at 6 months postoperatively, and the staged scored better than the single-stage (P < 0.05). At 12, 18, and 24 months after the operation, the outcome scores were not significantly different between the two groups. At follow-up, the ROM of the shoulder was not significantly different between the two groups. In the single-stage group, the outcome scores and ROM were similar for both shoulders and comparable to the staged group. We also found significant cost savings in the single-stage group (4440.89 ± 130.55 USD) compared to the staged group (5065.73 ± 254.76 USD) (p < 0.05). CONCLUSIONS: Patients receiving single-stage or staged bilateral arthroscopic rotator cuff repair showed similarly good clinical outcomes at follow-ups longer than 6 months. Moreover, good outcomes were observed on both sides of the single-stage group.

Autoinducer-2-mediated quorum-sensing system resists T4 phage infection in Escherichia coli.

In response to the restriction of nutrients and predation by natural enemies, bacteria have evolved complex coping strategies to ensure the reproduction and survival of individual species. Quorum sensing (QS) is involved in the bacterial response to phage predation and regulation of cellular metabolism. However, to date, no clear evidence exists regarding the involvement of autoinducer-2 (AI-2)-mediated QS systems in Escherichia coli in response to the challenges of nutrient restriction and phage infection. In this study, the role of the AI-2-mediated QS system in resisting T4 phage infection and regulating cell mechanisms in E. coli was revealed for the first time. This effect of the AI-2-mediated QS was achieved by simultaneously downregulating the T4 absorption site and carbon and glucose metabolism. Additionally, we found that lsrB, a metabolic brake, participates in AI-2-mediated regulation and maintenance of the normal metabolic balance of cells. The novel phage defense strategy and regulation and maintenance of cellular metabolism effectively limited the expansion of the phage population.