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1.
Ann Vasc Surg ; 100: 184-189, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37865169

RESUMO

BACKGROUND: The aim of this study was to assess the role of treatment of superficial venous reflux (SVR) in patients with combined deep segmental venous reflux as regards clinical symptoms as well as reflux improvement of the deep veins. METHODS: We reviewed 80 patients, retrospectively selected on the inclusion criteria and having combined SVR and segmental deep venous reflux who underwent SVR ablation. The contralateral limb of 44 patients was used as a control group, asked to wear compression stockings for 3 months during day time with no surgical intervention. Duplex ultrasounds follow-up was performed at 3, 6, and 12 months postoperatively. Clinical severity of venous disease was graded from C1 to C6 according to the CEAP (Clinical, Etiology, Anatomy, and Pathophysiology) classification. Duplex ultrasound was done in both supine and standing positions with non-weight-bearing of the examined limb. The venous reflux time, the venous flow volume and the peak venous flow velocity were registered. Removal of SVR was performed using either conventional surgery or radiofrequency ablation. The patient was required to wear compression stockings during the day time for the following weeks. RESULTS: During the follow-up period, all patients were improved clinically as regards pain, edema, and ulcer healing. All patients included in this study had no signs of residual SVR. Corrected deep venous segment reflux was in 36 (45%). Similar data at 3, 6, and 12 months postoperatively after SVR removal. The popliteal vein reflux responded less than the femoral vein reflux did. CONCLUSIONS: Treatment of the SVR eliminates segmental deep venous reflux in a good percentage of patients regardless of the treatment modality. Also, symptoms improvement and ulcer healing were documented, and hence, more studies are recommended to evaluate this role.


Assuntos
Doenças Vasculares , Insuficiência Venosa , Humanos , Úlcera , Estudos Retrospectivos , Resultado do Tratamento , Veia Femoral/diagnóstico por imagem , Insuficiência Venosa/diagnóstico por imagem , Insuficiência Venosa/cirurgia , Doença Crônica
2.
Ann Vasc Surg ; 106: 108-114, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38387797

RESUMO

BACKGROUND: In a kidney transplant tertiary referral center; we compared 3 operating team configurations of different surgical specialties to highlight the effect of the operating surgeon's specialty on various operative details and procedural outcome. METHODS: A total of 50 cases of living donor transplantations were divided into 3 main groups according to the operating surgeons' specialty, the first group (A) includes 12 patients exclusively operated on by urologists with advanced training in transplantation, the second group (B) includes 35 patients operated by combined surgical specialties; a urologist and a vascular surgeon both with advanced transplantation training, and a third group (C) includes 3 cases where the transplant operation commenced with operating urologists as in group (A) but required intraoperative urgent notification of a vascular surgeon to manage unexpected intraoperative technical difficulties or major complications. Cases were studied according to operative details, anastomosis techniques, ischemia times, total procedure time, recovery of urinary output, intensive care unit (ICU) stay, postoperative surgical complications and serum creatinine level for up to 3 years of follow-up. RESULTS: Study of operative details revealed that total duration of graft ischemia was significantly shorter in group (B) and significantly longer in group (C) (P value 0.001), Total procedural duration also varied significantly between the 3 groups, group (B) being the shortest while group (C) was the longest (P value less than 0.001). Technically; group (A) used only end to end arterial anastomosis as a standard technique, while group (B) used both end-to-end and end-to-side anastomoses as required per each case. End to side anastomosis in group (B) yielded better immediate graft response in the form of change in color, texture, earlier and more profuse postoperative urine volumes (P value 0.025). Furthermore, anastomosis to common and external iliac arteries (group B) yielded earlier and higher urine volumes than the internal iliac artery (P values 0.024 and 0.031 respectively). Group (B) recorded significantly less postoperative perigraft hematomas and lymphoceles compared to the other 2 groups. Equal rates of urine leaks, ICU stay, creatinine levels, patient and grafts survival rates among groups (A) and (B), while postoperative recovery and ICU stay duration were more lengthy in the complicated group (C). CONCLUSIONS: A vascular surgeon operating in a transplantation team would deal comfortably and efficiently with various vascular related challenges and complications, thus avoiding unnecessary time waste, complications and costs.

3.
Food Microbiol ; 122: 104559, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38839223

RESUMO

Listeria monocytogenes is a concerning foodborne pathogen incriminated in soft cheese and meat-related outbreaks, highlighting the significance of applying alternative techniques to control its growth in food. In the current study, eco-friendly zinc oxide nanoparticles (ZnO-NPs) were synthesized using Rosmarinus officinalis, Punica granatum, and Origanum marjoram extracts individually. The antimicrobial efficacy of the prepared ZnO-NPs against L. monocytogenes was assessed using the agar well diffusion technique. Data indicated that ZnO-NPs prepared using Origanum marjoram were the most effective; therefore, they were used for the preparation of gelatin-based bionanocomposite coatings. Furthermore, the antimicrobial efficacy of the prepared gelatin-based bionanocomposite coatings containing eco-friendly ZnO-NPs was evaluated against L. monocytogenes in Talaga cheese (an Egyptian soft cheese) and camel meat during refrigerated storage at 4 ± 1 oC. Talaga cheese and camel meat were inoculated with L. monocytogenes, then coated with gelatin (G), gelatin with ZnO-NPs 1% (G/ZnO-NPs 1%), and gelatin with ZnO-NPs 2% (G/ZnO-NPs 2%). Microbiological examination showed that the G/ZnO-NPs 2% coating reduced L. monocytogenes count in the coated Talaga cheese and camel meat by 2.76 ± 0.19 and 2.36 ± 0.51 log CFU/g, respectively, by the end of the storage period. Moreover, G/ZnO-NPs coatings controlled pH changes, reduced water losses, and improved the sensory characteristics of Talaga cheese and camel meat, thereby extending their shelf life. The obtained results from this study indicate that the application of gelatin/ZnO-NPs 2% bionanocomposite coating could be used in the food industry to control L. monocytogenes growth, improve quality, and extend the shelf life of Talaga cheese and camel meat.


Assuntos
Camelus , Queijo , Armazenamento de Alimentos , Gelatina , Listeria monocytogenes , Nanocompostos , Óxido de Zinco , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Queijo/microbiologia , Gelatina/química , Gelatina/farmacologia , Animais , Nanocompostos/química , Conservação de Alimentos/métodos , Carne/microbiologia , Microbiologia de Alimentos , Nanopartículas/química , Antibacterianos/farmacologia , Antibacterianos/química , Punica granatum/química , Contaminação de Alimentos/prevenção & controle , Contaminação de Alimentos/análise , Rosmarinus/química , Refrigeração , Extratos Vegetais/farmacologia , Extratos Vegetais/química
4.
Toxicol Ind Health ; 40(1-2): 52-58, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37983667

RESUMO

Male workers in copper smelting are exposed to copper, lead, and arsenic. This study aimed to assess the effects of combined exposure to these metals on male reproductive hormone levels and assesses malondialdehyde (MDA) as an oxidative stress parameter. The study was conducted on 40 copper smelter workers compared with 40 non-exposed workers. Laboratory investigations included levels of serum copper, blood lead, serum arsenic, follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone, and MDA. Levels of copper, arsenic, lead, FSH, and LH were significantly increased compared to controls. However, a statistically significant decrease in the mean value of testosterone was found among exposed workers. Positive correlations between serum copper and both serum FSH and MDA levels were statistically significant as were correlations between serum arsenic and MDA levels. Testosterone levels showed significant negative correlations with both copper and arsenic among exposed workers. A linear regression model of copper, arsenic, and lead levels as independent variables with FSH, LH, and testosterone as dependent variables revealed a significant negative association between serum copper and testosterone levels. The current study concluded that combined exposure to copper, arsenic, and lead in secondary copper smelters had a negative impact on male reproductive hormone levels that may be mediated by oxidative stress.


Assuntos
Arsênio , Cobre , Masculino , Humanos , Cobre/toxicidade , Chumbo/toxicidade , Hormônio Luteinizante , Hormônio Foliculoestimulante , Testosterona
5.
Food Microbiol ; 92: 103595, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32950137

RESUMO

During fresh apple packing, wash water in the dump tank and flume systems is reused during daily production, resulting in high levels of organic matter in the wash water. This study evaluated the antimicrobial efficacy of sodium acid sulfate (SAS), a Generally Recognized as Safe compound, against Listeria monocytogenes on fresh apples in a water system with high organic load. SAS at 1.0% reduced L. monocytogenes population in water with 1000 ppm chemical oxygen demand (COD) by more than 5.0 Log10 CFU/ml in 5 min, 2.0-3.0% SAS reduced L. monocytogenes to undetectable levels (10 CFU/ml) within 2 min regardless of organic levels. When applied on apples, a 2-min wash with SAS at 1.0, 1.5, 2.0, and 3.0% reduced L. monocytogenes by ~1.3, 1.9, 2.3, and 3.0 Log10 CFU/apple in clean water, respectively. High organic load in wash water up to 4000 ppm COD had no impact on the bactericidal effect of SAS against L. monocytogenes on fresh apples regardless of SAS concentrations. Shortening the contact time from 2 min to 30 s significantly reduced the antimicrobial efficacy of 25 ppm chlorine and 1.0-2.0% SAS but not that of 3.0% SAS. In addition, SAS at 1.0% demonstrated a better efficacy than 25 ppm chlorine in reducing fruit-to-water cross-contamination regardless of organic matter. SAS also showed a comparable efficacy as 25 ppm chlorine in reducing fruit-to-fruit cross-contamination in water with organic matter. The collective data indicate that SAS, as an enviroment-friendly compound, has the potential to be used as an alternative antimicrobial washing aid in dump tank process water intervention in apple packing facilities.


Assuntos
Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Água Doce/microbiologia , Listeria monocytogenes/efeitos dos fármacos , Malus/microbiologia , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Conservação de Alimentos/instrumentação , Água Doce/análise , Frutas/microbiologia , Listeria monocytogenes/crescimento & desenvolvimento
6.
Int J Mol Sci ; 21(9)2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32365915

RESUMO

Mycobacteriophages possess different sets of lytic enzymes for disruption of the complex cell envelope of the mycobacteria host cells and release of the viral progeny. Lysin B (LysB) enzymes are mycolylarabinogalactan esterases that cleave the ester bond between the arabinogalactan and mycolic acids in the mycolylarabinogalactan-peptidoglycan (mAGP) complex in the cell envelope of mycobacteria. In the present study, four LysB enzymes were produced recombinantly and characterized with respect to their enzymatic and antibacterial activities. Examination of the kinetic parameters for the hydrolysis of para-nitrophenyl ester substrates, shows LysB-His6 enzymes to be active against a range of substrates (C4-C16), with a catalytic preference towards p-nitrophenyl laurate (C12). With p-nitrophenyl butyrate as substrate, LysB-His6 enzymes showed highest activity at 37 °C. LysB-His6 enzymes also hydrolyzed different Tween substrates with highest activity against Tween 20 and 80. Metal ions like Ca2+ and Mn2+ enhanced the enzymatic activity of LysB-His6 enzymes, while transition metal ions like Zn2+ and Cu2+ inhibited the enzymatic activity. The mycolylarabinogalactan esterase activity of LysB-His6 enzymes against mAGP complex was confirmed by LC-MS. LysB-His6 enzymes showed marginal antibacterial activity when tested alone against Mycobacterium smegmatis, however a synergetic activity was noticed when combined with outer membrane permealizers. These results confirm that LysB enzymes are lipolytic enzymes with potential application as antimycobacterials.


Assuntos
Esterases/metabolismo , Micobacteriófagos/enzimologia , Proteínas Virais/metabolismo , Cobre/metabolismo , Esterases/química , Galactanos/metabolismo , Manganês/metabolismo , Peptidoglicano/metabolismo , Proteínas Virais/química , Zinco/metabolismo
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124082, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38479227

RESUMO

Heavy metals have been widely applied in industry, agriculture, and other fields because of their outstanding physics and chemistry properties. They are non-degradable even at low concentrations, causing irreversible harm to the human and other organisms. Therefore, it is of great significance to develop high accuracy and sensitivity as well as stable techniques for their detection. Raman scattering spectroscopy and atomic absorption spectrophotometer (AAS) were used parallelly to detect heavy metal ions such as Hg, Cd, and Pb of different concentrations in fish samples. The concentration of the heavy metals is varied from 5 ppb to 5 ppm. Despite the satisfactory recoveries of AAS, their drawbacks are imperative for an alternative technique. In Raman scattering spectroscopy, the intensities and areas of the characteristic peaks are increased with increasing the concentration of the heavy metals. For Hg concentration ≥ 1 ppm, a slight shift is observed in the peak position. The obtained values of peak intensity and peak area are modeled according to Elvoich, Pseudo-first order, Pseudo-second order, and asymptotic1 exponential model. The best modeling was obtained using the Elovich model followed by the asymptotic1 exponential model. The introduced Raman spectroscopy-based approach for on-site detection of trace heavy metal pollution in fish samples is rapid, low-cost, and simple to implement, increasing its visibility in food safety and industrial applications.


Assuntos
Mercúrio , Metais Pesados , Animais , Humanos , Análise Espectral Raman , Metais Pesados/análise , Mercúrio/análise , Peixes , Poluição Ambiental , Cádmio/análise , Monitoramento Ambiental
8.
Int J Food Microbiol ; 371: 109667, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35447560

RESUMO

A novel antimicrobial chitosan-gelatin based edible coating fortified with papaya leaves and thyme extract was prepared for improving the quality and shelf-life of chicken breast fillet and Kareish cheese during chilled storage at 4 ± 1 °C. The samples were dipped for 10 min in distilled water (control), chitosan-gelatin (CG), chitosan-gelatin +2% papaya leaves extract (CG + P) and chitosan-gelatin +2% thyme extract (CG + Th). The coated and uncoated samples were examined periodically for sensory attributes, pH, TBARs, total aerobic mesophilic (TAM), total Enterobacteriaceae (TE), and total yeasts and molds counts (TYM). Sensory evaluation revealed that chicken breast fillet and Kareish cheese samples coated with CG + P were the best in terms of tenderness, juiciness, body & texture and flavor. CG + Th exhibited the highest antimicrobial and antioxidant effect, followed by CG + P. The results of microbiological, physicochemical and sensory analysis of this study demonstrated that the application of CG + P or CG + Th could be a promising method for increasing the shelf life and improving the quality of chicken breast fillet and Kareish cheese.


Assuntos
Anti-Infecciosos , Carica , Queijo , Quitosana , Animais , Anti-Infecciosos/farmacologia , Queijo/microbiologia , Galinhas , Quitosana/farmacologia , Conservação de Alimentos/métodos , Gelatina , Extratos Vegetais , Folhas de Planta , Thymus (Planta) , Verduras
9.
Front Microbiol ; 10: 2462, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31787935

RESUMO

Contaminated food-contact surfaces are recognized as the primary reason for recent L. monocytogenes outbreaks in caramel apples and cantaloupes, highlighting the significance of cleaning and sanitizing food-contact surfaces to ensure microbial safety of fresh produce. This study evaluated efficacies of four commonly used chemical sanitizers at practical concentrations against L. monocytogenes biofilms on major food-contact surfaces including stainless steel, low-density polyethylene (LDPE), polyvinyl chloride (PVC), polyester (PET), and rubber. In general, efficacies against L. monocytogenes biofilms were enhanced by increasing concentrations of quaternary ammonium compound (QAC), chlorine, and chlorine dioxide, or extending treating time from 1 to 5 min. The 5-min treatments of 400 ppm QAC, 5.0 ppm chlorine dioxide, and 200 ppm chlorine reduced 3.0-3.7, 2.4-2.7, and 2.6-3.8 log10 CFU/coupon L. monocytogenes biofilms depending on surfaces. Peroxyacetic acid (PAA) at 160 and 200 ppm showed similar antimicrobial efficacies against biofilms either at 1- or 5-min contact. The 5-min treatment of 200 ppm PAA caused 4.0-4.5 log10 CFU/coupon reduction of L. monocytogenes biofilms on tested surfaces. Surface material had more impact on the efficacies of QAC and chlorine, less influence on those of PAA and chlorine dioxide, while organic matter soiling impaired sanitizer efficacies against L. monocytogenes biofilms independent of food-contact surfaces. Data from this study provide practical guidance for effective disinfection of food-contact surfaces in food processing/packing facilities.

10.
Biomolecules ; 10(1)2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31892223

RESUMO

Mycobacteriophage endolysins have emerged as a potential alternative to the current antimycobacterial agents. This study focuses on mycolylarabinogalactan hydrolase (LysB) enzymes of the α/ß-hydrolase family, which disrupt the unique mycolic acid layer of mycobacterium cell wall. Multiple sequence alignment and structural analysis studies showed LysB-D29, the only enzyme with a solved three-dimensional structure, to share several common features with esterases (lacking lid domain) and lipases (acting on long chain lipids). Sequence and structural comparisons of 30 LysB homology models showed great variation in domain organizations and total protein length with major differences in the loop-5 motif harboring the catalytic histidine residue. Docking of different p-nitrophenyl ligands (C4-C18) to LysB-3D models revealed that the differences in length and residues of loop-5 contributed towards wide diversity of active site conformations (long tunnels, deep and superficial funnels, shallow bowls, and a narrow buried cave) resembling that of lipases, cutinases, and esterases. A set of seven LysB enzymes were recombinantly produced; their activity against p-nitrophenyl esters could be related to their active site conformation and acyl binding site. LysB-D29 (long tunnel) showed the highest activity with long chain p-nitrophenyl palmitate followed by LysB-Omega (shallow bowl) and LysB-Saal (deep funnel).


Assuntos
Esterases/química , Esterases/metabolismo , Galactanos/metabolismo , Micobacteriófagos/enzimologia , Sequência de Aminoácidos , Esterases/genética , Modelos Moleculares , Simulação de Acoplamento Molecular , Conformação Proteica , Alinhamento de Sequência
11.
Front Microbiol ; 9: 2296, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30369909

RESUMO

Listeria monocytogenes contaminated processing equipment and the general packing environment have been implicated in deadly foodborne listeriosis outbreaks, highlighting the significance of proper sanitization and disinfection of food contact surfaces. This study aims to comprehensively evaluate antimicrobial efficacy of commercially available, economical sanitizers at practical concentrations against L. monocytogenes biofilm formed on polystyrene surfaces under different conditions. Ozonated water 1-min treatment at 1.0, 2.0, and 4.0 ppm resulted in ∼0.9, 3.4, and 4.1 log reduction of L. monocytogenes single strain biofilm grown on polystyrene surfaces, respectively. However, its efficacy was dramatically diminished in multi-strain L. monocytogenes biofilm and was further compromised by aged biofilm and in the presence of organic matter. Quaternary ammonium compounds (QAC) at 100/400 ppm, chlorine at 100/200 ppm, chlorine dioxide at 2.5/5.0 ppm and peroxyacetic acid (PAA) at 80/160 ppm resulted in 2.4/3.6, 2.0/3.1, 2.4/3.8, and 3.6/4.8 log reduction of L. monocytogenes single strain biofilm, respectively. Antimicrobial efficacies of all tested sanitizers against 7-day-old biofilm were much lower when compared to 2-day-old biofilm, with PAA being the least influenced by the age of the biofilm. Organic matter conditioning with diluted milk or apple juice dramatically impacted the antimicrobial efficacy of all sanitizers. PAA treatment of 1 min at 160-200 ppm resulted in a 3.2-3.5 log reduction against 7-day-old biofilm in the presence of organic matter, thus showing its effectiveness in eradicating L. monocytogenes biofilm on polystyrene surface. Collectively, data highlight the importance of timely and thoroughly cleaning food contact surfaces before disinfection and provides practical information and guidance for the food industry in selecting the most effective sanitizer in their sanitizing regimes to eliminate L. monocytogenes biofilm.

12.
Appl Biochem Biotechnol ; 183(1): 189-199, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28236193

RESUMO

A halophilic cellulase-producing bacterium was isolated from a sediment sample collected from Lake Qarun (Fayoum Province, Egypt). Molecular identification based on 16S rDNA amplification and sequencing revealed 99% homology with Halobacillus sp. and hence was designated as Halobacillus sp. QLS 31. Medium composition and culture conditions were optimized for enhancing the production of cellulase enzyme using the Plackett-Burman statistical design. Ten variables were evaluated for their influence on cellulase production. Carboxymethyl cellulose (CMC), zinc sulfate (ZnSO4), and inoculum size were found to exert a significant effect on cellulase productivity by Halobacillus sp. QLS 31. The maximum specific activity of cellulase enzyme was 48.08 U/mg. Following the predicted conditions, a 7.5-fold increase in cellulase specific activity (175.47 U/mg) was achieved compared to the basal medium (23.19 U/mg) under the following optimized conditions: temperature (30 °C), fermentation time (2 days ), pH value (9), CMC concentration (1%), inoculum size (1%), yeast extract concentration (0.1%), ammonium sulfate ((NH3)2SO4) concentration (0.1%), sodium chloride (NaCl) concentration (20%), and metal inducers: ZnSO4 (0.1%) and Ca/Mg ratio (0.01%). Thus, the results of this study provide an important basis for more efficient, cheap industrial cellulase production from halophilic Halobacillus sp. QLS 31.


Assuntos
Proteínas de Bactérias/biossíntese , Celulases/biossíntese , Halobacillus , Lagos/microbiologia , Microbiologia da Água , Proteínas de Bactérias/genética , Celulases/genética , Egito , Halobacillus/enzimologia , Halobacillus/genética , Halobacillus/isolamento & purificação
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