Microscopic Damage Research Articles

Microscopic, Macroscopic and Thermal Impact of Argon Plasma, Diode Laser, and Electrocoagulation on Ovarian Tissue.

To compare the microscopic, macroscopic and thermal damage inflicted to ovarian tissue by conventional monopolar and bipolar energy, argon plasma coagulation (APC) and diode laser. Bovine ovaries were used as a substitute for human tissue and subjected to the four aforementioned techniques and the inflicted damage was measured. Sixty fresh and morphologically similar cadaveric bovine ovaries were divided into five equal groups, each group was subjected to one of the following energy applications for both 1 and 5 s: Monopolar, bipolar electrocoagulation, diode laser, preciseAPC® and forcedAPC® Ovarian temperatures were measured at 4 and 8 s after treatment. Formalin-fixed ovarian specimens were examined by pathologists regarding macroscopic, microscopic and thermal tissue damage. None of the ovaries reached the temperature producing severe damage (40°C) after 1 s of energy transfer. Heating of adjacent ovarian tissue was least pronounced when preciseAPC® and monopolar electrocoagulation were applied (27.2±3.3°C and 28.2±2.9°C after 5 s of application, respectively). Conversely, 41.7% of the ovaries subjected to bipolar electrocoagulation for 5 s overheated. ForcedAPC® resulted in the most pronounced lateral tissue defects (2.8±0.3 mm after 1 s and 4.7±0.6 mm after 5 s). When the modalities were applied for 5 s, the electrosurgical instruments (mono- and bipolar) and preciseAPC® induced similar lateral tissue damage (1.3±0.6 mm, 1.1±1.6 mm and 1.2±1.3 mm, respectively). preciseAPC® created the shallowest defect of all the techniques (0.05±0.1 mm after 5 s of application). Our study hints at superior safety profiles of preciseAPC® and monopolar electrocoagulation compared to bipolar electrocoagulation, diode laser and forcedAPC® for ovarian laparoscopic surgery.

Clinicoradiological Study of Diffuse Axonal Injury: A Longitudinal Study

Introduction: Damage to the axons in neural brain tracts, corpus callosum, and brainstem, known as Diffuse Axonal Injury (DAI), can result in considerable morbidity and mortality in patients with head injuries. This type of injury involves microscopic damage and can have severe consequences. Aim: To investigate the incidence, clinical features, and radiological findings of DAI on Magnetic Resonance Imaging (MRI) and to associate MRI grading with neurological outcome using the Glasgow Outcome Scale (GOS). Materials and Methods: A longitudinal study was conducted in the Department of Neurosurgery, Jayarogya group of Hospitals, Gajra Raja Medical College, Gwalior,Madhya Pradesh, India, from December 2017 to November 2019. All the patients with Glasgow coma scores of eight or less with Computed Tomography (CT) and MRI brain findings consistent with DAI were included. The study collected data on patients including sociodemographic information, clinical variables related to trauma, details of hospital admission and stay, and variables related to the severity and consequences of DAI. Glasgow Coma Scale (GCS) was noted after resuscitation, MRI brain was done in stable patients. The neurological outcome was assessed after six months using the GOS and associated with MRI brain grading. The analyses were done using Statistical Package for Social Sciences (SPSS) version 26.0 and the frequencies were reported as percentages. Results: Total patients with head injury were N=694 and out of which patients with DAI n=94. The mean age was 33.97 years with a male:female ratio of 4.33:1. Grade 1, grade 2, and grade 3 MRI brain findings were present in 50% (N=50), 31.25% (N=20), and 18.75% (N=12) of cases. Most common site for contusions was parietal-temporo-occipital region found in 85.93% cases. Regarding functional outcome, poor outcome was observed in 26.67% (n=4) of grade II DAI and 75% (n=9) of patients of grade III DAI. Conclusion: DAI is major mechanism involved in Traumatic Brain Injury (TBI). In affected patients, long term hospitalisation is necessary. Patients with MRI grade I and II had a good outcome.

Effects of Strain Rate and Fiber Content on the Dynamic Mechanical Properties of Sisal Fiber Cement-Based Composites

In this paper, a split Hopkinson pressure bar (SHPB) was used to investigate the dynamic impact mechanical behavior of sisal fiber-reinforced cement-based composites (SFRCCs), and the microscopic damage evolution of the composites was analyzed by scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometry (EDS). The results show that the addition of sisal fibers improves the impact resistance of cement-based composite materials. Compared with ordinary cement-based composites (OCCs), the SFRCCs demonstrate higher post-peak strength, ductility, and energy absorption capacity with higher fiber content. Moreover, the SFRCCs are strain rate sensitive materials, and their peak stress, ultimate strain, and energy integrals all increase with increasing strain rate. From the perspective of fracture failure characteristics, the failure of OCCs is dominated by the brittle failure of crystal cleavage. In contrast, the failure mode of the SFRCCs changes to microscale matrix cracks, multi-scale pull-out interface debonding of fibers (fine filaments and bundles), and mechanical interlock. This research provides an experimental basis for the engineering application of high-performance and green cement-based composites.

In-Service Delaminations in FRP Structures under Operational Loading Conditions: Are Current Fracture Testing and Analysis on Coupons Sufficient for Capturing the Essential Effects for Reliable Predictions?

Quasi-static or cyclic loading of an artificial starter crack in unidirectionally fibre-reinforced composite test coupons yields fracture mechanics data-the toughness or strain-energy release rate (labelled G)-for characterising delamination initiation and propagation. Thus far, the reproducibility of these tests is typically between 10 and 20%. However, differences in the size and possibly the shape, but also in the fibre lay-up, between test coupons and components or structures raise additional questions: Is G from a coupon test a suitable parameter for describing the behaviour of delaminations in composite structures? Can planar, two-dimensional, delamination propagation in composite plates or shells be properly predicted from essentially one-dimensional propagation in coupons? How does fibre bridging in unidirectionally reinforced test coupons relate to delamination propagation in multidirectional lay-ups of components and structures? How can multiple, localised delaminations-often created by impact in composite structures-and their interaction under service loads with constant or variable amplitudes be accounted for? Does planar delamination propagation depend on laminate thickness, thickness variation or the overall shape of the structure? How does exposure to different, variable service environments affect delamination initiation and propagation? Is the microscopic and mesoscopic morphology of FRP composite structures sufficiently understood for accurate predictive modelling and simulation of delamination behaviour? This contribution will examine selected issues and discuss the consequences for test development and analysis. The discussion indicates that current coupon testing and analysis are unlikely to provide the data for reliable long-term predictions of delamination behaviour in FRP composite structures. The attempts to make the building block design methodology for composite structures more efficient via combinations of experiments and related modelling look promising, but models require input data with low scatter and, even more importantly, insight into the physics of the microscopic damage processes yielding delamination initiation and propagation.

Biosynthesis of nanocrystalline silver chloride with high antibacterial activity using bacterial extracts

The traditional synthesis of nano silver chloride involves chemical precipitation or physical methods. Due to the hazardous substances generated during the synthesis, it can cause environmental pollution. In this study, a green and facile method is described to biosynthesize nano-silver chloride with excellent antibacterial activity via in situ reduction of Ag + using the extract of Bacillus thuringiensis (Bt). Compared with previous reports, the minimal inhibition concentration (MIC) against Escherichia coli (E. coli) is 3.0 μg/mL, which is 2– to 800-fold higher than that of nano silver chloride. Subsequent in vitro studies involving agricultural bacteria such as Ralstonia solanacearum (R. solanacearum) revealed a 92.95% antibacterial rate when the concentration of nano-silver chloride was 2.0 μg/mL. Previous studies of antibacterial activity of nano-silver chloride focused more on the basic antibacterial properties without describing its antibacterial molecular mechanisms. The microscopic investigations and DNA damage experiments indicated that the nano-silver chloride adsorbed to the bacterial surface, leading to cell wall rupture, DNA damage, and cytoplasmic leakage. In addition, electron paramagnetic resonance (EPR) spectroscopy indicated the synthesis of reactive oxygen species (·OH, ·O2− and 1O2) in the bacteria. Our study provides evidence supporting the use of nano-silver chloride as an antibacterial agent in agriculture, and theoretical insight into the antibacterial mechanism thereof.

In situ observation of microscopic damage and crack initiation mechanisms in a filled EPDM

The paper presents a precise 3D quantification of damage evolution and eventual crack initiation due to metallic oxide particles and filler agglomerates in a peroxide crosslinked filled EPDM during uniaxial solicitation, thanks to synchrotron radiation X-ray Tomography. An in-situ tensile study using this technique reveals polymer debonding at the poles of all metallic oxide particles upon stretching. The cavities caused by this decohesion do not lead to crack initiation since they grow parallel to the applied stress direction. Conversely, crack always initiates from carbon black agglomerates (CBaggl). The crack initiation mechanism is a three step process that begins with the nucleation of cavities inside the CBaggl upon stretching. This is followed by the growth of these cavities which brings about the fracture of the agglomerates. Finally, this fracture can lead to the creation of a matrix crack at the origin of the material rupture. It is also confirmed that CBaggl that initiate the critical crack in the material are the biggest sized CBaggl and are located close to the edges of the sample.

Role of cyclooxygenase pathways in bowel fibrotic remodelling in a murine model of experimental colitis.

Gut fibrosis occurs under chronic inflammation. This study examined the effects of different cyclooxygenase (COX) inhibitors on fibrosis in the inflamed colon. Colitis was induced by 2,4-dinitrobenzenesulfonic acid (DNBS) in albino male Sprague-Dawley rats. After 6, 12 and 18 days, macroscopic and microscopic damage, collagen and elastic fibre content were examined. At day 6, pro-fibrotic factors (collagen I and III, hydroxyproline, fibronectin, matrix metalloproteinase-2 and -9), transforming growth factor-beta (TGF-β) signalling [TGF-β, Ras homolog gene family member A (RhoA), phosphorylated small mother against decapentaplegic (pSMAD)-2 and -6] and peristalsis were assessed, and the effects of indomethacin, SC-560 or celecoxib were tested. Six days after DNBS administration, significant histopathological signs of fibrotic remodelling were observed in rats. At day 6, pro-fibrotic factors were up-regulated and colonic peristalsis was altered. COX inhibitors reversed the histochemical, molecular and functional changes in the fibrotic colon. COX inhibition reduced TGF-β expression, SMAD2 phosphorylation and RhoA, and increased SMAD6 expression. Colonic fibrosis is associated with altered bowel motility and induction of profibrotic factors driven by TGF-β signalling. COX-1 and COX-2 inhibition counteracts this fibrotic remodelling by the modulation of TGF-β/SMAD signalling, mainly via SMAD6 induction and reduction in SMAD2 phosphorylation.

Effectiveness of carbonate removal and demineralization inhibition in primary teeth using a 9.3-μm carbon dioxide laser

BackgroundStudies on permanent dental enamel have shown that irradiation with a 9.3-μm carbon dioxide (CO2) laser can safely inhibit caries progression in vivo and carieslike lesion formation in vitro. The authors conducted a study to investigate whether 9.3-μm CO2 laser irradiation could safely inhibit carieslike lesion formation in primary teeth in vitro. MethodsTeeth were irradiated with a 9.3-μm CO2 laser at a pulse fluence of 0.8 J/cm2 and scanned automatically over a target area of 5.8 mm2. Two test groups of 15 extracted human molars each were used: (1) laser-irradiated and (2) laser-irradiated plus additional fluoride. Both groups used nonirradiated areas as nonlaser-treated controls. After irradiation, artificial carieslike lesions were generated through a validated pH-cycling protocol. Relative mineral loss (ΔZ) was determined by cross-sectional microhardness testing in depth. Fourier transform infrared spectroscopy was performed on additional 10 irradiated samples to investigate the removal of acid-soluble carbonate groups from the mineral. ResultsInhibition of carieslike lesion formation relative to untreated enamel was (1) laser-irradiated alone: 56.2%, (2) fluoride alone: 55.0%, (3) laser plus fluoride: 76.5% (significantly different from 1 and 2; P < 0.01). Carbonate removal by laser irradiation (SD) was 50.4% (7.7%) at the surface and detectable to a depth of at least 14 μm. ConclusionIrradiation with 9.3-μm CO2 laser on primary teeth reduced the formation of carieslike lesions and was associated with significant removal of acid-soluble carbonate groups from the enamel mineral. This inhibition was accomplished without an unsafe rise in pulpal temperature and without significant microscopic or visible damage to the enamel surface.

In-Situ Extraction of Space Morphology of Electrical Tree Channel in Silicone Gel

This work uses the laser scanning confocal microscope (LSCM) to propose a method for the 3-D fluorescence imaging of electrical trees inside silicone gel, which is used as an insulating material for packaging in power electronic devices. It induces auto-fluorescence in the electrical trees in the silicone gel through laser light to reveal their micro-morphology. The laser light source focuses on the damaged area, and points on different focal planes are successively scanned by using the confocal microscope for the 3-D in situ fluorescence imaging of the electrical trees. Automatic path regression is used to reconstruct the area of the channel of microscopic damage inside the material in situ. The global and local parameters of the electrical trees are statistically calculated from the obtained images to quantitatively analyze their morphology. The calculation found that the diameter of electrical trees was mainly distributed between 4.47– <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$32.27~\mu \text{m}$ </tex-math></inline-formula> , and the average diameter of electric branch channels decreased with the increase of voltage frequency. The proposed method provides a novel and feasible technical means for the non-destructive detection of electrical trees inside materials.

Jailed pressure wire technique for coronary bifurcation lesions: structural damage and clinical outcomes

Introduction and objectivesThe use of a pressure wire as a jailed wire to evaluate side branch results during provisional stenting seems feasible. However, safety concerns exist due to the mechanical damage of the wire and the lack of prospective data evaluating the prognosis of patients treated using this technique. This study sought to evaluate the structural damage of the pressure wire in patients treated using the jailed pressure wire technique and to assess mid-term clinical outcomes. MethodsWe enrolled 99 patients with single bifurcation lesions and provisional stenting as the strategy of choice. A jailed pressure wire was used to guide side branch intervention according to the instantaneous wave-free ratio (iFR). A total of 114 patients and the respective nonpolymer-coated jailed wires were used as historical controls. Guidewire damage was evaluated by stereomicroscopy. The primary endpoint was significant microscopic damage. Major adverse cardiac events were evaluated at 2-year follow-up. ResultsSignificant microscopic damage was more frequent in pressure wires than in nonpolymer-coated wires (53.5% vs 22.8%, P<.001). There were no fractures in either group. There were fewer side branch interventions in the pressure wire group (postdilation/kissing balloon, 32.3% vs 56.1%, P=.001; stenting, 0.0% vs 2.6%, P=.104). The 2-year rate of major adverse cardiac events was similar between the 2 groups (HRadj, 0.42; 95%CI, 0.10-1.73; P=.229). ConclusionsPressure wires were less resistant to jailing than conventional nonpolymer-coated wires. Patients treated with iFR-guided provisional stenting required fewer side branch interventions but had similar 2-year clinical outcomes than patients treated with the angiography-guided technique.

A Phase Field Model for the Damage and Fracture of Multiple Network Elastomers

Abstract This work develops a continuum phase field model for predicting the damage initiation and crack propagation in multiple network elastomers. Previous researches have revealed that failure of multiple network elastomers involves microscopic damage initiation by the chain scission of filler network and macroscopic fracture by penetrating crack of matrix network. However, most existing models for multiple network elastomers only deal with its finite deformation and strain softening process, which are unable to capture the initiation and propagation of cracks. In this work, to bridge the microscopic damage and the macroscopic fracture of multiple network elastomers in the finite deformation model, we incorporate the phase field variable of crack surface density to model the crack propagation and the internal damage variable to model the chain scission. By forming a multi-field variational framework, the developed model can be used to simulate the macroscopic deformation and fracture of multiple network elastomers. Through a finite element implementation of the phase field model, previous experiment results obtained from uniaxial tension and unilateral fracture can be well predicted. Moreover, experimentally observed damage zone formed by sacrificing filler network to achieve toughening effect is also numerically illustrated in simulation, giving much clearer pictures for the contributions of different energy dissipation mechanisms.

Weathering of a Nonwoven Polypropylene Geotextile: Field vs. Laboratory Exposure.

Like other plastic materials, geosynthetics can undergo changes in their properties due to weathering. These changes must be known and, if necessary, duly accounted for in the design phase. This work evaluates the resistance of a nonwoven polypropylene geotextile to weathering, both in the field (under natural degradation conditions) and in the laboratory (under accelerated degradation conditions). The damage experienced by the geotextile in the field weathering tests was evaluated by monitoring changes in its physical (mass per unit area and thickness), mechanical (tensile, tearing and puncture behaviour) and hydraulic (water permeability normal to the plane) properties. Microscopic damage was assessed by scanning electron microscopy. In the laboratory weathering tests, only the tensile behaviour of the geotextile was monitored. The results showed that all geotextile properties were affected by weathering. The mechanical strength of the geotextile decreased in the field weathering tests. Microscopic transverse cracks were found in the weathered polypropylene fibres, which may explain the reduction in mechanical strength. The accumulation of dirt on the nonwoven structure altered the physical and hydraulic properties of the geotextile. Comparing the field and laboratory weathering tests, the reduction in tensile strength found after 24 months outdoors (roughly 30%) was very similar to that observed after 4000 h in the laboratory. This relationship may not be valid for other geotextiles or other exposure locations.

New nonlocal multiscale damage model for modelling damage and cracking in quasi-brittle materials

A new method for the simulation of crack initiation and propagation in quasi-brittle materials is proposed that combines the scaled boundary finite element method and a nonlocal multiscale damage model. The scaling centre of the scaled boundary finite element subdomain is taken as the material point. Microscopic damage is defined in terms of the stretch rate of bonds of material points, and macroscale topologic damage is evaluated as the weighted average of microscale damage over bonds in the influence domain. Through the energetic degradation function of phase field analysis, which connects energy-based damage and macroscale topologic damage, the nonlocal multiscale damage model is inserted into the framework of the scaled boundary finite element method. The quadtree discrete mesh technique is used to rapidly obtain a high-quality multilevel mesh by taking full advantage of the hanging nodes that it allows. A detailed arc length method for solving nonlinear equations is also presented in this paper. Four typical examples, one Mode I and three mixed-mode cracking simulations, show that the proposed method can be used to simulate crack initiation and propagation in quasi-brittle materials and correctly describe crack propagation paths and load-deformation curves. Compared with other methods, the nonlocal multiscale damage model presented in this paper can provide a more accurate description of local cracking damage zones, and the results are more reasonable, with higher calculation accuracy and efficiency. The numerical examples also indicate that there is no mesh sensitivity problem when the mesh size of the damage process region is less than 1/5 of the radius of the influence domain.

Effects of volatile organic contamination on the performance of dielectric film

The volatile organic contamination (VOC) of polymer materials can cause degradation of optical components performance. For two types of polymer materials commonly used in high-power laser facility: polyethylene terephthalate-ethylene glycol (PET-G) and polytetrafluoroethylene (PTFE), the contaminated dielectric film samples were obtained by rapid volatilization of polymer materials at high temperatures. The effects of VOC on microscopic morphology, spectral performance and laser damage performance of the dielectric film were researched. The results showed that the VOC of two types of materials would lead to spectral shift, reflectivity change and laser damage performance deterioration of dielectric film. Compared with PET-G, the VOC of PTFE has a more serious impact on the performance of the dielectric film. The performance deterioration of the dielectric film can be clarified by analyzing the VOC and the surface micro-morphology. Research results can be used to estimate the performance degradation of dielectric films for long-term storage and usage. And they have a guiding significance for the selection of environmental materials of optical components.

Evaluation of Microscopic Damage of PEEK Polymers under Cyclic Loadings Using Molecular Dynamics Simulations.

Full-atomic molecular dynamics simulations were conducted to investigate the time evolution of microscopic damage in polyetheretherketone (PEEK) polymers under cyclic loading conditions. Three characteristics were used to quantify microscopic damage: entropy, distribution of the end-to-end distance of polymers, and the volume fraction of voids. Our results show that the degree of disentanglement of polymers and the volume fraction of voids increase with cyclic loading, which may lead to entropy generation. Uniaxial tensile strength simulations of the polymer system before and after cyclic loading were performed. The tensile strength after cyclic loading was lower than that before loading. Furthermore, two systems with the same entropy and different loading histories showed almost the same strength. These results imply that entropy generation is expressed as the total microscopic damage and can potentially be employed for effective evaluation of the degradation of material characteristics.

Antibacterial Mechanism of Chitosan-Gentamicin and Its Effect on the Intestinal Flora of Litopenaeus vannamei Infected with Vibrio parahaemolyticus.

To explore the application of chitosan-gentamicin conjugate (CS-GT) in inhibiting Vibrio parahaemolyticus (V. parahaemolyticus), which is an important pathogen in aquatic animals worldwide, the antimicrobial activity of CS-GT and the effects of a CS-GT dose on the intestine histopathology and intestinal flora of V. parahaemolyticus-infected shrimps were explored. The results showed that CS-GT possessed broad-spectrum antibacterial activity, with minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and half inhibitory concentration (IC50) of 20.00 ± 0.01, 75.00 ± 0.02 and 18.72 ± 3.17 μg/mL for V. parahaemolyticus, respectively. Further scanning electron microscope and cell membrane damage analyses displayed that the electrostatic interaction of CS-GT with cell membrane strengthened after CS grafted GT, resulting in leakage of nucleic acid and electrolytes of V. parahaemolyticus. On the other hand, histopathology investigation indicated that high (100 mg/kg) and medium (50 mg/kg) doses of CS-GT could alleviate the injury of a shrimp's intestine caused by V. parahaemolyticus. Further 16S rRNA gene sequencing analysis found high and medium dose of CS-GT could effectively inhabit V. parahaemolyticus invasion and reduce intestinal dysfunction. In conclusion, CS-GT possesses good antibacterial activity and could protect shrimps from pathogenic bacteria infection.

Corrosion resistance of polyurethane grouting material in landfill site

Landfill has been a common way to deal with municipal solid waste. It is critical to prevent the leakage of landfill leachate with corrosivity and biotoxicity in landfill sites. Non-aqueous reacting polyurethane grouting material has been demonstrated to have excellent water-barrier performance. This study aimed to verify the feasibility of non-aqueous reacting polyurethane grouting material application to landfills. The corrosion resistance of the grouting material was investigated using laboratory immersion tests with 14 chemical solvents. The corrosion resistance was evaluated based on the weight gain rate of polyurethane samples and their microscopic damage. The test results show that the polyurethane grouting material showed good resistance to acids (sulfuric acid, nitric acid and propionic acid), salt solutions (calcium chloride, ferric chloride, zinc sulfate and lead acetate) and landfill leachate. However, methyl phenol could lead to chemical degradation. Hydrochloric acid, gasoline and ammonia may cause minor damage to polyurethane. The results are expected to provide reference for evaluating the chemical corrosion resistance of polyurethane grouting materials in landfill sites.

Physical-Mechanical Properties of Bamboo-Textile-Reinforced Polymer Made with Vacuum-Assist Resin Transfer Molding

ABSTRACT Bamboo fiber-reinforced polymers have been widely studied as natural fiber composites. This study fabricated a continuous bamboo-textile-reinforced polymer (BTRP) composite by using woven bamboo strips and epoxy through vacuum-assisted resin transfer molding (VA-RTM). The physical properties, including bulk density and equilibrium moisture content, of various BTRP specimens with different textile architectures, stacking sequences, loading axes, and numbers of layers were preliminarily evaluated. The specimens’ flexural properties, including strength, modulus, integral load – deflection relationship, damage parameters, and fractography characteristics, were also examined. As the number of layers increased, the flexural strength decreased but modulus values increased. When the number of layers was constant, the plain-woven BTRP specimens had slightly higher strength and modulus values than did the twill-woven specimens. The BTRP specimens exhibited remarkable mechanical properties and staged failure behaviors unique to laminated materials. Moreover, the stiffness of the specimens was attenuated before reaching the ultimate load, which was attributed to microscopic interphase damage, and the various architectures affected the specimens’ fracture modes. The gradual multistage failure modes of the specimens imply that the fabricated composite is relatively safe for use. According to these results, the fabricated composite incorporates the advantages of VA-RTM and continuous nontwisted bamboo strips, indicating that it has substantial commercial potential.

Effect of Garlic Extract on Liver Histopathology of BALB/c Mice with Nicotine Exposure

Nicotine affects liver in the presence of free radicals. One of the antioxidants is allicin which is the most abundant organosulfur in garlic. The objective of this study is to determine the effect of garlic extract as an antioxidant on the liver histopathological features of BALB/c mice exposed to nicotine. This is an experimental study with with post-test only control group design. The research subject were 24 male BALB/c mice. The K- group was the healthy control. The K+ group was exposed to inhaled nicotine of 10 mg/kgBW. Groups P1 and P2 were exposed to 10 mg/kgBW inhaled nicotine and were given garlic extract 300 mg/kgBW and 500 mg/kgBW. Treatment was given for 14 days. Data were analyzed by Kruskal-Wallis test and considered significant if the p value 0.05 with 95% confidence interval. Liver degeneration was grouped into normal, parenchymatous degeneration, hydropic degeneration, and necrosis. The results in the following groups: K: 80%, 20%, 0%, 0%; K(-) :0%,0%,87%,13% ; P1 : 0%,60%,40%,0%; P2 : 0%,100%,0%,0%. There was a significant difference in the degree of degeneration between groups (p=0.001). Garlic extract can reduce the degree of microscopic damage to the liver of BALB/c mice exposed to nicotine inhalation.

Dry Eye Following Femtosecond Laser-Assisted Cataract Surgery: A Meta-Analysis.

This study investigates the dry eye effect after femtosecond laser-assisted cataract surgery (FLACS) and also compares the risk of postoperative dry eye between FLACS and manual cataract surgery (MCS). We searched various databases between 1 January 2000 and 15 October 2022 and included peer-reviewed clinical studies in our review. Dry eye parameters were extracted at baseline and postoperative day one, week one, one month, and three months. Parameters included were the ocular surface discomfort index (OSDI), tear secretion (tear meniscus height, Schirmer's test), microscopic ocular surface damage (fluorescein staining), and tear stability (first and average tear breakup time). Additionally, the differences of each parameter at each time point were compared between FLACS and MCS. In total, six studies of 611 eyes were included. On postoperative day one, increased, pooled standardised mean differences (SMDs) were noted in the OSDI, tear secretion, tear film instability, and microscopic damage. During postoperative week one, dry eye worsened. Fortunately, dry eye achieved resolution afterwards and nearly returned to the baseline level at postoperative three months. When the parameters were compared between FLACS and MCS, those of FLACS had higher severities, but most were not statistically significant. Dry eye impact was approximately the same in FLACS and MCS at postoperative three months.