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The evolution of lower extremity reconstruction
No full textReconstruction of the lower extremity is a complex task that has evolved greatly in both technique and indication over the past century. Early advances in treating traumatic lower extremity injuries focused on primary amputation to avoid the high mortality of infection. The introduction of antibiotics improved surgical debridement and local reconstructive options, enhancing the viability of lower extremities with simple and proximal defects. With the advent of microvascular surgery, free tissue transfer techniques provided a means to reconstruct more distal and complex problems. As these surgical techniques have continued to evolve, so too have indications for reconstruction, patient management and post-operative care-now with a greater emphasis on patient quality of life and limb function. The purpose of this article is to outline the evolution of lower extremity reconstruction, and how the standard of practice has changed over time
Repeat laparoscopic anatomical liver resection in a hepatocellular carcinoma patient: a case report
No full textAnatomical resection (AR) has been reported to achieve better long-term outcomes than non-anatomical resection for the treatment of hepatocellular carcinoma (HCC). The surgical feasibility and oncological significance of laparoscopic AR (LAR), especially “subsegment resection”, “cone unit resection”, and repeat LAR for HCC, remain unproven. We present a 67-year-old patient with alcoholic liver cirrhosis and HCC who underwent full LAR three times, focusing on the technical aspects of the Glissonean approach. Repeating LAR for recurrent HCC could be a safe and feasible procedure. However, HCC recurred in the neighboring segment twice, even though pathological vascular invasion and marginal remnants were not confirmed. We should investigate the oncological significance and advancements in subsegmentectomy and cone unit resection, in the future
Daily atrial fibrillation issues: the view-point of a practicing surgeon
No full textAtrial Fibrillation (AF) is encountered daily by the cardiac surgeon. How to deal with a patient with pre existing AF who is on anticoagulation taking into account urgency, type of anticoagulation and procedure planned are some of the daily considerations encountered. When to start anticoagulation and other pharmacotherapy after the occurrence of post-op atrial fibrillation and the use of ablative therapies in view of bleeding and other complications are daily judgement calls made by surgeons. Whom to offer combined interventions are decisions the surgeon faces daily. While guidelines help in broad strokes, there is little help for individual situations which is due to structural problems and absence of universal definitions resulting in the lack of granular data needed for practical individualized daily decision making
Stroke risk and anticoagulation in the setting of post-cardiac surgery atrial fibrillation: a systematic review of the literature
No full textPostoperative atrial fibrillation (POAF) affects up to 50% of patients undergoing cardiac surgery. It remains unclear to what extent POAF increases the stroke risk and whether anticoagulation is warranted in this setting. The primary objective of this review was to conduct a systematic review of the evidence for a correlation between POAF and stroke. Further, we sought to evaluate the published evidence on anticoagulation in the setting of POAF to prevent stroke. To this end, we performed a comprehensive literature search to identify studies on POAF in patients undergoing cardiac surgery with stroke as an outcome. To date, eight meta-analyses providing pooled estimates of the stroke risk associated with POAF in patients undergoing cardiac surgery have been published. The reported pooled odds ratios range from 1.36 to 4.09 for unadjusted estimates. Additionally, five studies were identified that evaluated the impact of anticoagulation on stroke in the setting of POAF. Of these, three supported the use of anticoagulants, and two studies were inconclusive. This systematic review did not find strong supporting evidence that POAF is causally related to stroke, despite a strong correlation with comorbidities and all-cause mortality in the literature. Available evidence to date suggests an elevated risk of bleeding with no clear reduction in stroke or other thromboembolic events when anticoagulation is initiated in the setting of POAF. An upcoming randomized clinical trial by the Cardiothoracic Surgery Network group will hopefully provide clarification on the recommendations for anticoagulation in the setting of POAF after cardiac surgery
Analysis of measures against mechanical complications in circumferential minimally invasive surgery for adult spinal deformity
No full textAim: We evaluated the reduction of mechanical complications (MCs) in circumferential minimally invasive spinal surgery (c-MIS) to treat adult spinal deformity (ASD) using lateral lumbar interbody fusion and a percutaneous pedicle screw.Methods: Patients with ASD who underwent c-MIS with a follow-up period of > 24 months were enrolled. Groups were as follows: c-MIS using 5.5 mm rods (P group), c-MIS using a 5.5 mm single rod with cement augmentations in the upper instrumented vertebra (UIV)/UIV + 1 (B group), c-MIS using 6 mm rods (6P group), and multi-rod c-MIS (M group). Terminal rod contour was optimized to prevent proximal junctional kyphosis (PJK) in the P, 6P, and M groups. Patients were divided into an MC group, consisting of 68 patients with MCs, and a non-MC group, consisting of 78 patients without MCs. We examined various spinopelvic- and implant-related parameters between the groups.Results: Overall, 146 patients with ASD who underwent c-MIS were included. The incidence of PJK was significantly lower in the P and M groups than in the B group, and rod fracture was significantly lower in the M group than in the B and P groups. In the MC group, preoperative PT, postoperative PI-LL, and PSA were significantly larger than those in the non-MC group. Use of the 5.5 mm single rod and postoperative PI-LL were significant risk factors for MCs. Conclusion: The complication incidence decreased with improvements in surgical techniques and measures. Use of the 5.5 mm single rod and postoperative PI-LL were significant risk factors for MCs
HIV-1 Tat induced microglial EVs leads to neuronal synaptodendritic injury: microglia-neuron cross-talk in NeuroHIV
No full textAim: Activation of microglial NLRP3 inflammasome is an essential contributor to neuroinflammation underlying HIV-associated neurological disorders (HAND). Under pathological conditions, microglia-derived-EVs (MDEVs) can affect neuronal functions by delivering neurotoxic mediators to recipient cells. However, the role of microglial NLRP3 in mediating neuronal synaptodendritic injury has remained unexplored to date. In the present study, we sought to assess the regulatory role of HIV-1 Tat induced microglial NLRP3 in neuronal synaptodendritic injury. We hypothesized that HIV-1 Tat mediated microglia EVs carrying significant levels of NLRP3 contribute to the synaptodendritic injury, thereby affecting the maturation of neurons.Methods: To understand the cross-talk between microglia and neuron, we isolated EVs from BV2 and human primary microglia (HPM) cells with or without NLRP3 depletion using siNLRP3 RNA. EVs were isolated by differential centrifugation, characterized by ZetaView nanoparticle tracking analysis, electron microscopy, and western blot analysis for exosome markers. Purified EVs were exposed to primary rat neurons isolated from E18 rats. Along with green fluorescent protein (GFP) plasmid transfection, immunocytochemistry was performed to visualize neuronal synaptodendritic injury. Western blotting was employed to measure siRNA transfection efficiency and the extent of neuronal synaptodegeneration. Images were captured in confocal microscopy, and subsequently, Sholl analysis was performed for analyzing dendritic spines using neuronal reconstruction software Neurolucida 360. Electrophysiology was performed on hippocampal neurons for functional assessment.Results: Our findings demonstrated that HIV-1 Tat induced expression of microglial NLRP3 and IL1β, and further that these were packaged in microglial exosomes (MDEV) and were also taken up by the neurons. Exposure of rat primary neurons to microglial Tat-MDEVs resulted in downregulation of synaptic proteins- PSD95, synaptophysin, excitatory vGLUT1, as well as upregulation of inhibitory proteins- Gephyrin, GAD65, thereby implicating impaired neuronal transmissibility. Our findings also showed that Tat-MDEVs not only caused loss of dendritic spines but also affected numbers of spine sub-types- mushroom and stubby. Synaptodendritic injury further affected functional impairment as evidenced by the decrease in miniature excitatory postsynaptic currents (mEPSCs). To assess the regulatory role of NLRP3 in this process, neurons were also exposed to Tat-MDEVs from NLRP3 silenced microglia. Tat-MDEVs from NLRP3 silenced microglia exerted a protective role on neuronal synaptic proteins, spine density as well as mEPSCs.Conclusion: In summary, our study underscores the role of microglial NLRP3 as an important contributor to Tat-MDEV mediated synaptodendritic injury. While the role of NLRP3 in inflammation is well-described, its role in EV-mediated neuronal damage is an interesting finding, implicating it as a target for therapeutics in HAND
Studies of leaf water content in smart agriculture using THz technologies: a review
No full textIn recent years, the concept of smart agriculture has entered our collective daily routine by radically modifying the methods by which crop monitoring was previously carried out. More precisely, the term smart farming focuses its attention on the use technologies already present on the market like, sensors (multispectral, hyperspectral, thermal and terahertz sensors), WNS (wireless sensor network) and drones capable to reduce the human work in the fields, optimizing at the same time the quantity and quality of the products limiting the use of resources, as water, fertilizers, pesticides and herbicides. Recently, one of the most important problem in the field of precision farming is the availability of water; unfortunately, this factor becomes more critical from year to year. To resolve this problem, the first step is to reduce consumption and rationalize the use of water by adjusting the water supply to the needs of the systems in order to increase its yield while saving money. In this respect, the development of non-destructive techniques operating in the THz spectral region has allowed to monitor in real time the water content present in leaves and plants. In fact, due to the strong water absorption and reflection in this spectral region, this feature can be exploited to detect the water content of leaves and plants helping us to intervene promptly in cases where the plant needs water, avoiding so does water stress, but above all trying to use our primary resource adequately by reducing waste. About this, Imaging and Time-Domain Spectroscopy (THz-TDS) techniques have been applied to monitor soil conditions, drought stress and presence of pathogens on the plants. In this review, we focus our attention on the latest research carried out on monitoring the water content present in leaves through THz technologies. Moreover, we pose particular attention in the description of our system set composed by a 97 GHz transmitter-receiver able to analyze the spatial distribution of the water inside a leaf
Nanostructured heterogeneous photocatalyst materials for green synthesis of valuable chemicals
No full textThe photocatalytic process employing nanostructured semiconductor materials has attracted great attention in energy production, CO2 reduction, and water/air purification for decades. Recently, applying heterogeneous photocatalyst for the synthesis of valuable chemicals is gradually emerging and considered as a promising process for the conversion of cheap resources (i.e., biomass derivatives, polyols, and aromatic hydrocarbons). Compared with traditional thermal catalytic approaches, the photocatalytic process provides a mild reaction condition and flexible platform (photocatalyst) that allows precise tweaking of reaction intermediates and reaction pathways, thus resulting in fine control of the selective synthesis of specialized chemicals that are challenging for thermal catalysis. In this review, we summarize recent achievements in photocatalytic synthesis of various industrial important chemicals via photo-oxidative and photo-reductive processes. The selective oxidation of alcohols and aromatics, epoxidation of alkenes, hydrogenation of gaseous molecules and hydrocarbons, and coupling reactions by means of various photocatalysts including metal oxides, supported plasmonic metal nanostructures, conjugated organic polymers, anchored homogeneous catalysts, and dye-sensitized heterostructures are discussed from a material perspective. In addition, fundamental understandings of reaction mechanisms and rational design of nanostructured photocatalysts for enhancing efficiency, selectivity, and stability are discussed in detail
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