15 research outputs found
Blood Pressure and Blood Pressure Deficits as Predictors of Acute Kidney Injury in Vasopressor Dependent Patients Post Cardiovascular Surgery
BACKGROUND: Acute kidney injury (AKI) is a common and serious post-operative complication following cardiovascular surgery.
AIM: The aim of the study was to evaluate the value of blood pressure and blood pressure deficits as predictors of AKI in post cardiovascular surgery vasopressors’ dependent patients.
METHODS: A prospective observational, single center study, conducted on 100 patients requiring vasopressor support for more than 4 h after cardiovascular surgery. All included patients were subjected to the measurements of three or more systolic arterial pressure (SAP), diastolic arterial pressure (DAP), and mean arterial pressure (MAP) readings from the ward charts before surgery and the mean of these measures was calculated, was recorded and pre-operative systolic perfusion pressure (SPP), diastolic perfusion pressure (DPP), and mean perfusion pressure (MPP) were calculated. A vasopressor-associated average values for hemodynamic pressure-related parameters (SAP, DAP, MAP, CVP, SPP, DPP, and MPP) were calculated on the 1st 24 h after admission. The percent deficit in post-operative average parameters in relation to pre-operative parameters was determined as % parameter deficit.
RESULTS: The pre-operative SAP, DAP, MAP, SPP, DPP, and MPP were significantly higher in the non-AKI compared to AKI patients while pre-operative central venous pressure (CVP) was significantly higher in AKI patients. The post-operative DAP, MAP, DPP, and MPP were also higher in non-AKI and the post-operative CVP was lower in non-AKI compared to AKI patients.
CONCLUSIONS: This study concluded that the relative decrease in the perfusion pressures could be significant predictors of AKI after cardiovascular surgery in vasopressor dependent patients. The higher pre- or post-operative CVP or its relative decrease after cardiac surgery was seen also to be associated with higher incidence of AKI
Right mini-thoracotomy versus median sternotomy for mitral valve replacement
Background: The advantages of minimally invasive mitral valve surgery over the conventional approach is still debated. This study aimed to evaluate early outcomes after mitral valve replacement (MVR) using the right mini-thoracotomy (RMT) versus median sternotomy (MS).
Methods: We prospectively included 60 patients who had MVR from May 2015 to June 2017. We classified patients into two groups; Group A (n= 30) had RMT, and Group B (n= 30) had MS. Postoperative pain score, wound satisfaction, and clinical and echocardiographic outcomes were compared between both groups.
Results: The mean age was 39.90 ± 12.34 years in Group A and 45.75 ± 13.10 years in Group B (p= 0.08). Preoperative and echocardiographic data showed no statistical significance difference between the groups. Group A had longer aortic cross-clamp (118.85 ± 40.56 vs. 70.75 ± 24.81 minutes, p<0.001) and cardiopulmonary bypass times (186.70 ± 67.44 vs. 104.65 ± 42.60 minutes, p<0.001). Group B had more blood loss (565 ± 344.3 vs. 241.5 ±89.16 ml/24 hours, p<0.001). The median pain score was 1 (range: 1- 3) in Group A and 4 (2- 8) in Group B (p<0.001), and the median wound satisfaction was 1.5 (1- 4) in Group A and 4 (1- 7) in Group B (p<0.001). Wound infection occurred in 1 (3.3%) patient in Group A and 6 (20%) patients in Group B (p=0.04).
Conclusion: Mitral valve replacement through the right mini-thoracotomy could be a safe alternative to median sternotomy. The right mini-thoracotomy was associated with longer operative times but better pain and wound satisfaction scores and lower wound infection
Solvent-Free Synthesis, In Vitro and In Silico Studies of Novel Potential 1,3,4-Thiadiazole-Based Molecules against Microbial Pathogens
A new series of 1,3,4-thiadiazoles was synthesized by the reaction of methyl 2-(4-hydroxy-3-methoxybenzylidene) hydrazine-1-carbodithioate (2) with selected derivatives of hydrazonoyl halide by grinding method at room temperature. The chemical structures of the newly synthesized derivatives were resolved from correct spectral and microanalytical data. Moreover, all synthesized compounds were screened for their antimicrobial activities using Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Bacillus subtilis, Staphylococcus aureus, and Candida albicans. However, compounds 3 and 5 showed significant antimicrobial activity against all tested microorganisms. The other prepared compounds exhibited either only antimicrobial activity against Gram-positive bacteria like compounds 4 and 6, or only antifungal activity like compound 7. A molecular docking study of the compounds was performed against two important microbial enzymes: tyrosyl-tRNA synthetase (TyrRS) and N-myristoyl transferase (Nmt). The tested compounds showed variety in binding poses and interactions. However, compound 3 showed the best interactions in terms of number of hydrogen bonds, and the lowest affinity binding energy (−8.4 and −9.1 kcal/mol, respectively). From the in vitro and in silico studies, compound 3 is a good candidate for the next steps of the drug development process as an antimicrobial drug
l-Methioninase from some Streptomyces isolates I: Isolation, identification of best producers and some properties of the crude enzyme produced
Among 60 isolates of Streptomyces tested; only 40 isolates were capable to utilize l-methionine as the only source of nitrogen in medium. In addition, 24 of these isolates could grow in medium amended with l-methionine as a source of nitrogen and carbon. Qualitative rapid plate assay test shows the ability of 18 of these isolates to grow with a pink color surrounding their colonial growth, while 6 of these isolates could grow and utilize l-methionine without any pink color around their colonial growth. Quantitative assay test shows the rate of l-methioninase production by all isolates tested. Permeabilization treatment including chemical and physical methods proved that l-methioninase was found to be extracellularly produced. The results also indicate that l-methioninase production was not correlated with growth rate or l-methionine consumption in medium. On the other hand, quantitative assay test shows that these six isolates were l-methioninase negative and failed to produce any amount of l-methioninase. In addition, results also show that isolates No. 4 and No. 60 were the most suitable for l-methioninase production, these two isolates were characterized and identified as Streptomyces sp. DMMMH 4 and Streptomyces sp. MDMMH 60 using 16S rRNA with accession No. in gene bank. Furthermore, optimal conditions for enzyme activity produced by the two isolates were established in relation to temperature, pH, reaction time and type of buffer used and its molarities
Regulation of the antibiotic elution profile from tricalcium phosphate bone cement by addition of bioactive glass
Abstract This work aimed at tailoring of different properties of antibacterial drug delivery Ca-phosphate cements by incorporation of bioactive glass (BG). The cements were prepared from beta-tricalcium phosphate cement (β-TCP) and BG based on 50 SiO2—20 CaO—15 Na2O—7 B2O3—4 P2O5—4 Al2O3 wt% with different percentages of BG [5, 10, 15, and 20% (w/w)]. The composite cements were characterized by XRD, FTIR, and TEM. Moreover, in vitro bioactivity and biodegradation were evaluated in the simulated body fluid (SBF) at 37 °C. In addition, physical properties and mechanical strength were determined. Also, the effect of glass addition on the drug release profile was examined using gentamicin. Finally, the antimicrobial activity was studied against Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumonia bacteria, one unicellular fungal strain (Candida albicans), and one multicellular fungal strain (Mucor racemosus). The results showed that after soaking in SBF, the compression strength values ranged from 14 to 36 MPa, the bulk densities and porosities were within 1.35 to 1.49 g/cm3 and 51.3 to 44.71%, respectively. Furthermore, gentamicin was released in a sustained manner, and BG decreased the released drug amount from ~ 80% (in pure β-TCP) to 47–53% in the composite cements. A drug release profile that is sustained by all samples was achieved. The antimicrobial test showed good activity of gentamicin-conjugated cements against bacteria and fungi used in this study. Additionally, cytotoxicity results proved that all samples were safe on MG-63 cells up to 50 µg/mL with no more than 7–12% dead cells. From the view of the physico-mechanical properties, bioactivity, biodegradation, and drug release rate, 20BG/β-TCP sample was nominated for practical bone grafting material, where it showed appropriate setting time and a relatively high mechanical strength suitable for cancellous bone
Development of Antimicrobial Laser-Induced Photodynamic Therapy Based on Ethylcellulose/Chitosan Nanocomposite with 5,10,15,20-Tetrakis(m-Hydroxyphenyl)porphyrin
The development of new antimicrobial strategies that act more efficiently than traditional antibiotics is becoming a necessity to combat multidrug-resistant pathogens. Here we report the efficacy of laser-light-irradiated 5,10,15,20-tetrakis(m-hydroxyphenyl)porphyrin (mTHPP) loaded onto an ethylcellulose (EC)/chitosan (Chs) nanocomposite in eradicating multi-drug resistant Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans. Surface loading of the ethylcelllose/chitosan composite with mTHPP was carried out and the resulting nanocomposite was fully characterized. The results indicate that the prepared nanocomposite incorporates mTHPP inside, and that the composite acquired an overall positive charge. The incorporation of mTHPP into the nanocomposite enhanced the photo- and thermal stability. Different laser wavelengths (458; 476; 488; 515; 635 nm), powers (5–70 mW), and exposure times (15–45 min) were investigated in the antimicrobial photodynamic therapy (aPDT) experiments, with the best inhibition observed using 635 nm with the mTHPP EC/Chs nanocomposite for C. albicans (59 ± 0.21%), P. aeruginosa (71.7 ± 1.72%), and S. aureus (74.2 ± 1.26%) with illumination of only 15 min. Utilization of higher doses (70 mW) for longer periods achieved more eradication of microbial growth
Production and optimization of novel Sphorolipids from Candida parapsilosis grown on potato peel and frying oil wastes and their adverse effect on Mucorales fungal strains
Abstract Brief introduction Mucormycosis disease, which has recently expanded with the Covid 19 pandemic in many countries, endangers patients' lives, and treatment with common drugs is fraught with unfavorable side effects. Aim and objectives This study deals with the economic production of sophorolipids (SLs) from different eight fungal isolates strains utilizing potato peels waste (PPW) and frying oil waste (FOW). Then investigate their effect against mucormycetes fungi. Results The screening of the isolates for SLs production revealed the highest yield (39 g/100 g substrate) with most efficiency was related to a yeast that have been identified genetically as Candida parapsilosis. Moreover, the characterizations studies of the produced SLs by FTIR, 1H NMR and LC–MS/MS proved the existence of both acidic and lactonic forms, while their surface activity was confirmed by the surface tension (ST) assessment. The SLs production was optimized utilizing Box-Behnken design resulting in the amelioration of yield by 30% (55.3 g/100 g substrate) and ST by 20.8% (38mN/m) with constant level of the critical micelle concentration (CMC) at 125 mg/L. The studies also revealed the high affinity toward soybean oil (E24 = 50%), in addition to maintaining the emulsions stability against broad range of pH (4–10) and temperature (10–100℃). Furthermore, the antifungal activity against Mucor racemosus, Rhizopus microsporus, and Syncephalastrum racemosum proved a high inhibition efficiency of the produced SLs. Conclusion The findings demonstrated the potential application of the SLs produced economically from agricultural waste as an effective and safer alternative for the treatment of infection caused by black fungus
Follicular dendritic cells
Follicular dendritic cells (FDCs) are unique accessory immune cells that contribute to the regulation of humoral immunity. They are multitasker cells essential for the organization and maintenance of the lymphoid architecture, induction of germinal center reaction, production of B memory cells, and protection from autoimmune disorders. They perform their activities through both antigen-driven and chemical signaling to B cells. FDCs play a crucial role in the physiological regulation of the immune response. Dis-regulation of this immune response results when FDCs retain antigens for years. This provides a constant antigenic stimulation for B cells resulting in the development of immune disorders. Antigen trapped on FDCs is resistant to therapeutic intervention causing chronicity and recurrences. Beyond their physiological immunoregulatory functions, FDCs are involved in the pathogenesis of several immune-related disorders including HIV/AIDS, prion diseases, chronic inflammatory, and autoimmune disorders. FDCs have also been recently implicated in rare neoplasms of lymphoid and hematopoietic tissues. Understanding FDC biology is essential for better control of humoral immunity and opens the gate for therapeutic management of FDC-mediated immune disorders. Thus, the biology of FDCs has become a hot research area in the last couple of decades. In this review, we aim to provide a comprehensive overview of FDCs and their role in physiological and pathological conditions
Thyroid Dysfunction and Its Relation to Myocardial Performance Among Patients with Acute Myocardial Infarction
Background: The cardiovascular system is one of the most important targets on which thyroid hormones act, thyroid hormone has a major role in the cardiovascular system function and cardiac hemodynamics. Objectives: The primary aim of our study was to evaluate the prevalence of thyroid dysfunction in patients with acute myocardial infarction and to study the impact of these dysfunctions on in-hospital morbidity and mortality among those subjects. Patients and Methods: This study was conducted on one hundred critically ill patients admitted to the critical care department with the diagnosis of acute myocardial infarction in the period from April 2017 to January 2019. Results: According to thyroid profile, 78 patients (78%) had euthyroid status and the remaining 22 patients (22%) had thyroid dysfunctions which include: 12 patients (54.54%) were euthyroid sick syndrome, 7 patients (13.81%) had subclinical hypothyroidism, 3 patients (13.63%) had subclinical hyperthyroidism. Conclusion: Thyroid dysfunction in association with acute myocardial infarction affect the myocardial performance and this was evident in our study by lower ejection fraction, higher initial killip class, higher wall motion score index, and increased myocardial performance index compared to those with normal thyroid status but it has no impact on the in-hospital mortality
Antimicrobial and antibiofilm activities of the fungal metabolites isolated from the marine endophytes <i>Epicoccum nigrum</i> M13 and <i>Alternaria alternata</i> 13A
Epicotripeptin (1), a new cyclic tripeptide along with four known cyclic dipeptides (2–5) and one acetamide derivative (6) were isolated from seagrass-associated endophytic fungus Epicoccum nigrum M13 recovered from the Red Sea. Additionally, two new compounds, cyclodidepsipeptide phragamide A (7) and trioxobutanamide derivative phragamide B (8), together with eight known compounds (9–16), were isolated from plant-derived endophyte Alternaria alternata 13A collected from a saline lake of Wadi El Natrun depression in the Sahara Desert. The structures of the isolated compounds were determined based on the 1D and 2D NMR spectroscopic data, HRESIMS data, and a comparison with the reported literature. The absolute configurations of 1 and 7 were established by advanced Marfey’s and Mosher’s ester analyses. The antimicrobial screening indicated that seven of the tested compounds exhibited considerable (MIC range of 2.5–5 µg/mL) to moderate (10–20 µg/mL) antibacterial effect against the tested Gram-positive strains and moderate to weak (10–30 µg/mL) antibacterial effect against Gram-negative strains. Most of the compounds exhibited weak or no activity against the tested Gram-negative strains. On the other hand, four of the tested compounds showed considerable antibiofilm effects against biofilm forming Gram-positive and Gram-negative strains