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1.
J Neurosurg ; : 1-6, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38457799

RESUMO

OBJECTIVE: Treatment of intracranial aneurysms by flow diversion is safe and effective and is increasingly popular. However, the correct treatment paradigm for aneurysms incompletely treated by initial placement of a flow diverter has not been established, nor have the subsequent natural history and occlusion rates of such aneurysms. The authors sought to outline the natural history of such aneurysms, which to date have been considered partially treated. METHODS: The authors retrospectively reviewed consecutive cases from 6 high-volume neurointerventional services, including all cases in which the first follow-up imaging after placement of a flow diverter showed incomplete occlusion of the aneurysm, and for which subsequent clinical and/or radiological follow-up was available. All included patients were treated with the Pipeline Flex embolization device or the Pipeline Flex embolization device with Shield Technology. Subsequent radiographic and clinical outcome data were collected and analyzed using the Kaplan-Meier survival function. RESULTS: A total of 263 patients with persistently patent aneurysms on first follow-up imaging after flow diversion were identified. Of these, 204 had clinical follow-up and 152 had additional imaging follow-up. Of this final cohort, 148 aneurysms were unruptured, and 4 were ruptured. The average aneurysm size by maximum dimension was 10.8 mm. The average recorded follow-up was 27.8 months in the cohort, with some patients followed for as long as 9 years from treatment. Over the course of 403 person-years of follow-up, no delayed aneurysm ruptures were recorded. Both with and without retreatment, aneurysms showed a trend toward progressive occlusion over time. Complications related to device placement were low. CONCLUSIONS: Aneurysms that have been incompletely treated by flow diversion have a benign natural history with progression toward occlusion over time, with or without retreatment.

2.
Cardiol Rev ; 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38334371

RESUMO

Rapid deployment/sutureless (RDS) valves have recently emerged as an innovative surgical solution, providing an alternative to traditional methods of surgical aortic valve replacement (SAVR) by eliminating the need for suture placement and tying. This innovation leads to a reduction in aortic crossclamp and cardiopulmonary bypass times, enhancing the efficiency of the procedure. Among the 2 available RDS valves, the Edwards Intuity valve in particular has been demonstrated to be a particularly promising substitute in the field of SAVR. The Intuity valve distinguishes itself from other RDS and conventional valves by yielding superior outcomes, such as a significant reduction in mortality, increase in the longevity of the valve, and a marked decrease in both mean and peak transvalvular pressure gradients. These benefits collectively contribute to its appeal as a favorable new solution. However, further investigation is needed to conclusively determine the long-term outcomes and safety of RDS valves. Nevertheless, the utilization of the Intuity valve presents an exciting solution to the existing limitations of conventional and minimally invasive SAVR, especially for patients afflicted with severe aortic stenosis.

3.
Eur J Dent ; 18(1): 14-25, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36870328

RESUMO

The field of dentistry has seen various technological advances regarding caries detection, some lesions still prove to be difficult to detect. A reasonably new detection method, near-infrared (NIR), has shown good results in caries detection. This systematic review aims to compare NIR with conventional methods in terms of caries detection. Online databases (PubMed, Scopus, ScienceDirect, EBSCO, and ProQuest) were used for the literature search. The search was performed from January 2015 till December-2020. A total of 770 articles were selected, of that 17 articles qualified for the final analysis as per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The articles were assessed according to a modified Critical Appraisal Skills Programme checklist, and then synthesis of the review started. The inclusion criteria were clinical trials done in vivo on teeth with active caries of vital or nonvital teeth. This review excluded nonpeer reviewed articles, case reports, case series, opinions, abstracts, non-English written articles, studies of subjects with arrested caries, or teeth with developmental defects of tooth structure and teeth having environmental defects of tooth structure, as well as in-vitro studies. The review compared near-infrared technology with radiography, visual inspection, and laser fluorescence in terms of caries detection, sensitivity, specificity, and accuracy. The sensitivity of NIR ranged from 99.1 to 29.1%. Studies showed that NIR exhibited higher sensitivity for occlusal enamel and dentin caries. The specificity of NIR ranged from 94.1 to 20.0%. In enamel and dentinal occlusal caries, NIR demonstrated lower specificity than that of radiograph. The specificity of NIR in early proximal caries was low. Accuracy was determined in 5 out of 17 studies where the values ranged from 97.1 to 29.1%. The accuracy of NIR was the highest for dentinal occlusal caries. NIR shows promising evidence as an adjunct in caries examination due to its high sensitivity and specificity; however, more studies are required to determine its full potential in different situations.

4.
Front Public Health ; 11: 1277056, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38045967

RESUMO

Introduction: Healthcare workers have a significant chance of experiencing violence, with physical violence impacting anywhere from 8 to 38% of healthcare professionals throughout their careers. Besides physical abuse, many healthcare workers are subject to verbal aggression or threats, with patients and visitors being the most frequent sources of such incidents. Methods: This research examines the work atmosphere of healthcare professionals at Kasr Al-Aini University Hospital in Cairo, Egypt, during the pandemic. The study aims to evaluate the frequency of violence toward healthcare workers and health professionals training through a cross-sectional survey conducted among them. The research was conducted on Egyptian healthcare workers over 6 months, from November 2020 until the end of January 2021, using convenience sampling in a cross-sectional study. Over half of the respondents reported experiencing violence. Results: Among those who experienced violence, 93% reported verbal aggression, 43% reported physical and verbal abuse, and 59% claimed that violence increased during the pandemic. Additionally, 97% of those who experienced violence reported it occurring within the 4 months following the survey. About 42.5% of the respondents were female, and nearly 65% were over 30. 82% of the respondents did not receive training on handling violence while performing their job. Conclusion: This study highlights the high prevalence of verbal assaults in healthcare settings, primarily by patients' families or acquaintances. Despite reporting such incidents, most respondents did not see any significant government action. Furthermore, the COVID-19 pandemic did not significantly change the frequency of violent incidents, indicating that the root causes of violence are systemic and extend beyond the pandemic. These findings underscore the need for systemic changes in healthcare organizations to address and prevent violence against healthcare workers.


Assuntos
COVID-19 , Violência no Trabalho , Humanos , Feminino , Masculino , Estudos Transversais , Pandemias , COVID-19/epidemiologia , Pessoal de Saúde , Hospitais Universitários
5.
Langmuir ; 39(50): 18518-18525, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38055533

RESUMO

The Sauter mean diameter, d32, is a representative parameter in emulsions that indicates the average size of the oil droplets once the emulsion becomes stable. Several mathematical and physical approaches have been employed in the literature to seek expressions for d32 under different conditions. The present work sheds light on this rich literature and emphasizes that the characterization of emulsions is still a fertile field for investigation. In this paper, a new Π-theorem-based model to predict the normalized Sauter mean diameter for the specific case of rotor-stator emulsification is sought by applying a multiple regression analysis on experimental data of oil-in-water (O-W) emulsions produced using three different oils: paraffin, soybean oil, and isopropyl myristate, at different oil-to-water (O/W) ratios and rotor speeds. The proposed model quantifies the roles of the viscous, inertial, and interfacial tension forces, besides the O/W ratio, in the emulsification process within the turbulent inertial subrange. The developed empirical correlation is then contrasted with relevant literature models for reliability assessment; predictions of the present explicit model are proven to be more accurate for the fluid properties and the experimental conditions under study.

6.
Ann Med Surg (Lond) ; 85(5): 1496-1501, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37228953

RESUMO

This study aims to assess the trends of emergency department (ED) visits among kidney transplant recipients in a high-volume transplant centre. Methods: This retrospective cohort study targeted patients who underwent renal transplantation at a high-volume transplant centre from 2016 to 2020. The main outcomes of the study were ED visits within 30 days, 31-90 days, 91-180 days, and 181-365 days of transplantation. Results: This study included 348 patients. The median (interquartile range) age of patients was 45.0 years (30.8, 58.2). Over half of the patients were male (57.2%). There was a total of 743 ED visits during the first year after discharge. 19% (n=66) were considered high-frequency users. High-volume ED users tended to be admitted more frequently as compared to those with low frequencies of ED visits (65.2% vs. 31.2%, respectively, P<0.001). Conclusion: As evident by the large number of ED visits, suitable coordination of management through the ED remains a pivotal component of post-transplant care. Strategies addressing prevention of complications of surgical procedures or medical care and infection control are aspects with potential for enhancement.

7.
J Pers Med ; 13(5)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37241011

RESUMO

BACKGROUND: Uterine blood flow determines endometrial thickness. This study examined how vaginal sildenafil citrate and estradiol valerate altered endometrial thickness, blood flow, and fertility in infertile women. METHODS: This study observed 148 infertile women whose infertility was unexplained. Group 1 comprised 48 patients who received oral estradiol valerate (Cyclo-Progynova 2 mg/12 h white tablets) from day 6 till ovulation was initiated with clomiphene citrate. A number of 50 participants in group 2 received oral sildenafil (Respatio 20 mg/12 h film-coated tablets) for 5 days starting the day after their previous menstrual period and finishing on the day they ovulated with clomiphene citrate. Group 3 was the control group, with 50 patients receiving clomiphene citrate (Technovula 50 mg/12 h tablets) ovulation induction from the 2nd to 7th day of cycle. All patients had transvaginal ultrasounds to determine ovulation, follicle count, and fertility. Miscarriage, ectopic pregnancy, and multiple pregnancies were monitored for three months. RESULTS: The three groups' mean ETs differed statistically at p = 0.0004. A statistically significant difference was found between the three groups in terms of the number of follicles, with 69% of patients in group 1 having one and 31% having two or more, 76% of patients in group 2 having one and 24% having two or more, and 90% of patients in the control group having one and 10% having two or more (p = 0.038). The clinical pregnancy rates of the three groups were 58%, 46%, and 27%, respectively (p = 0.005). The distribution of all side effects was not statistically different between the three groups. CONCLUSION: It is possible to claim that adding oral estrogen to clomiphene citrate therapy as an adjuvant therapy can improve endometrial thickness and, as a result, increase the pregnancy rates in unexplained infertility compared to sildenafil, especially in cases where the infertility has lasted less than two years. Most people who take sildenafil end up with a mild headache.

8.
Healthcare (Basel) ; 11(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37108018

RESUMO

(1) Background: COVID-19 caused the worst international public health crisis, accompanied by major global economic downturns and mass-scale job losses, which impacted the psychosocial wellbeing of the worldwide population, including Saudi Arabia. Evidence of the high-risk groups impacted by the pandemic has been non-existent in Saudi Arabia. Therefore, this study examined factors associated with psychosocial distress, fear of COVID-19 and coping strategies among the general population in Saudi Arabia. (2) Methods: A cross-sectional study was conducted in healthcare and community settings in the Saudi Arabia using an anonymous online questionnaire. The Kessler Psychological Distress Scale (K-10), Fear of COVID-19 Scale (FCV-19S) and Brief Resilient Coping Scale (BRCS) were used to assess psychological distress, fear and coping strategies, respectively. Multivariate logistic regressions were used, and an Adjusted Odds Ratio (AOR) with 95% Confidence Intervals (CIs) was reported. (3) Results: Among 803 participants, 70% (n = 556) were females, and the median age was 27 years; 35% (n = 278) were frontline or essential service workers; and 24% (n = 195) reported comorbid conditions including mental health illness. Of the respondents, 175 (21.8%) and 207 (25.8%) reported high and very high psychological distress, respectively. Factors associated with moderate to high levels of psychological distress were: youth, females, non-Saudi nationals, those experiencing a change in employment or a negative financial impact, having comorbidities, and current smoking. A high level of fear was reported by 89 participants (11.1%), and this was associated with being ex-smokers (3.72, 1.14-12.14, 0.029) and changes in employment (3.42, 1.91-6.11, 0.000). A high resilience was reported by 115 participants (14.3%), and 333 participants (41.5%) had medium resilience. Financial impact and contact with known/suspected cases (1.63, 1.12-2.38, 0.011) were associated with low, medium, to high resilient coping. (4) Conclusions: People in Saudi Arabia were at a higher risk of psychosocial distress along with medium-high resilience during the COVID-19 pandemic, warranting urgent attention from healthcare providers and policymakers to provide specific mental health support strategies for their current wellbeing and to avoid a post-pandemic mental health crisis.

9.
Sci Rep ; 13(1): 6456, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081046

RESUMO

Coronavirus Disease 2019 (COVID-19) continues to spread rapidly. Monoclonal antibodies as well as anti-tumor necrosis factor are considered promising treatments for COVID-19. A prospective cohort study in which patients are divided into three groups. Group 1: moderate and severe COVID-19 patients received standard treatment; Group 2: moderate and severe COVID-19 patients received tocilizumab; Group 3: moderate and severe COVID-19 patients received treatment with infliximab and tocilizumab. 153 patients were recruited in the study. 40 received standard treatment alone, 70 received tocilizumab with standard treatment, and 43 received tocilizumab/infliximab with standard treatment. There was a significant difference in length of hospital stay (10.3, 8.9, and 7.6 days respectively P = 0.03), need for a non-invasive mechanical ventilator (4, 5, and one patient; P = 1.2E-8), intensive care admission (32, 45, and 16 patients; P = 2.5E-5), the occurrence of sepsis (18, 12, and 10 patients; P = 0.005) and in death (42.5%, 14.2%, and 7%; P = 0.0008) which were significantly lower in tocilizumab/infliximab group compared to tocilizumab and standard of care groups. Our study showed that tocilizumab/ infliximab in addition to standard of care was considered a promising treatment for moderate and severe COVID-19 patients.Trial registration number: ClinicalTrials.gov NCT04734678; date of registration: 02/02/2021.


Assuntos
COVID-19 , Humanos , Infliximab/uso terapêutico , SARS-CoV-2 , Síndrome da Liberação de Citocina/tratamento farmacológico , Estudos Prospectivos , Resultado do Tratamento , Tratamento Farmacológico da COVID-19 , Estudos Retrospectivos
10.
Egypt Heart J ; 75(1): 12, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36780088

RESUMO

BACKGROUND: Low-level laser therapy (LLLT) is a promising noninvasive physiotherapeutic approach that has been demonstrated to improve cardiac performance. This study aimed to assess the impact of low-level laser therapy on cardiac functions and clinical status in patients with chronic left ventricular systolic heart failure who were not candidates for cardiac revascularization or resynchronization. A case series of 27 patients received a course of low-level laser physiotherapy, the clinical outcomes, echocardiographic parameters, and serum nitric oxide levels were evaluated before and after LLLT. RESULTS: Of the total patients enrolled in the study, 21 (or 77.8%) were male, with a mean age of 57.7 ± 6.89 years. NYHA classification significantly improved after low-level laser therapy, 15 patients were in class III,12 were in class IV, and no one was in class II before laser therapy while after laser therapy; 25 patients shifted to class II, two patients were in class III with P < 0.001, Six-minute walk distance test was performed, and the results showed that the mean of 6MWT was less than 200 m (148.556 ± 39.092) before the study but increased to more than 300 after laser therapy (385.074 ± 61.740), left ventricular ejection fraction before laser therapy was 26 ± 7.5 while after laser therapy it became 30 ± 8.6 but diastolic function did not change after low-level laser therapy, the mean peak TR pressure was 40.0 ± 9.0 mmHg and 33.0 ± 7.0 before and after laser therapy respectively P < 0.001. A significant change was observed in NO level from 4.1 ± 1.4 IU/ml before laser therapy to 5.2 ± 1.7 IU/ml after laser therapy P < 0.001. CONCLUSIONS: Low-level laser therapy may add benefits to improve symptoms, clinical condition, and quality of life in patients with left ventricular systolic dysfunction, further studies are necessary to evaluate the changes in cardiac functions at a longer follow-up duration.

11.
J Public Health Res ; 12(1): 22799036221147100, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36779072

RESUMO

Background: Youth represent 21% of the Egyptian population; such proportion can create a leading demographic power for economic development and transition. However, with the current COVID-19 pandemic, everyone is exposed to more than usual stressors, adding a burden to their mental health and well-being. Aim: This study aims to understand the pandemic's effect on youth's mental health in Egypt to strengthen the intervention areas needed to tackle such issues. Methods: This observational, analytical, cross-sectional study employed internet platforms of Facebook & WhatsApp groups for a web-based survey that included 412 respondents between 15 and 30 years old. RESULTS The median age of the respondents was 22 years. At least 30% reported increased violence in the street and/or household, and 27.4% of the respondents have considered visiting a psychiatrist during the last period. Conclusion: It is evident that the current situation is unprecedented and challenging for everyone; however, some populations are more vulnerable than others. Thus, it's important to support young people to ensure that the whole community can withstand the pandemic. The governments should support and mitigate some of the stresses that can be directly amended, like the education and job security concerns.

12.
BMC Public Health ; 22(1): 2438, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36575430

RESUMO

BACKGROUND: In recognition of the risk factors common between oral diseases and various chronic conditions and the intersection between oral health and some sustainable development goals, the current cross-sectional study was designed to quantify the burden of dental caries and identify factors associated with its occurrence in permanent teeth. METHODS: Using data from Egypt's population-based survey (2013-2014), two individual-level outcomes; past caries experience (DMFT > 0) and presence of untreated carious lesions (DT > 0) were assessed using the WHO basic methods for oral health surveys. Information on potential explanatory variables including sociodemographic characteristics, exposure to fluoridated water, dental attendance, and dental anxiety was gathered using a structured questionnaire. Stratified multistage cluster random sampling was used to recruit survey participants. Multivariable logistic regression was performed to identify significant potential risk factors for caries in the permanent dentition of Egyptians. FINDINGS: A total of 9,457 participants were included of which 70.3% had at least one untreated carious lesion. After adjusting for all covariates, analphabetic Egyptians were found to have significantly higher odds of caries experience in permanent dentition DMFT > 0 (OR 1.54, 95% CI [1.20-1.98]), DT > 0 (OR 1.62, 95% CI [1.32-2.00]). Males, however, had significantly lower caries risk DMFT > 0 (OR 0.75, 95% CI [0.67-0.85]), DT > 0 (OR 0.81, 95% CI [0.73-0.89]) when compared to females. Regarding age, mean DMFT scores were significantly lower in age groups (6-15 years) (OR 0.03, 95% CI [0.014; 0.082]), (16- 20 years) (OR 0.09, 95% CI [0.037; 0.23]), and (21-35 years) (OR 0.22, 95% CI [0.09; 0.53]) than among people ≥ 60 years. CONCLUSION: Addressing individual-level caries risk factors should be complemented by addressing upstream factors to reduce burden of untreated dental caries among Egyptians.


Assuntos
Cárie Dentária , Dentição Permanente , Masculino , Feminino , Humanos , Criança , Adolescente , Egito/epidemiologia , Estudos Transversais , Cárie Dentária/epidemiologia , Índice CPO , Prevalência
13.
Materials (Basel) ; 15(19)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36234137

RESUMO

Joining dissimilar sheet thicknesses of AA6082-T6 alloys by friction stir spot welding (FSSW) provides many advantages in automotive and aerospace applications. The formed keyhole at the end of the FSSW process is one of the typical features after the welding process, which owns the same size as the rotating pin that remains at the joint center. This keyhole destroys the joint continuity and can stimulate serious stress concentration when the FSSW joint bears an external force. To solve this issue, a novel refilling technique was developed for the FSSW keyholes using a friction stir deposition (FSD) technique. The FSSW joints of AA6082-T6 sheets were welded at various rotation speeds from 400 to 1000 rpm and a constant dwell time of 3 s, where a 2 mm sheet thickness was an upper sheet, and a 1 mm sheet thickness was a lower sheet. All the keyhole refilling processes were achieved using a specially designed AA2011-T6 consumable rod to be used for friction stir deposition of continuous layers at a constant deposition parameter of 400 rpm consumable rod rotation speed and a 1 mm/min feed rate. The heat input energy for both the FSSW and refilled FSSW lap joints was calculated. In addition, the FSSW and the FSD temperatures were measured. Macrostructure, microstructure, and mechanical properties in terms of hardness and tensile shear maximum load were evaluated for both the friction stir spot welded (FSSWed) and the refilled FSSW lap joints. The obtained results showed that the keyhole could be successfully refilled with defect-free continuous multilayers after the refill friction stir spot welding (RFSSW) process. All the RFSSW lap joints showed higher tensile shear loads than that given by the FSSW (before refill) lap joints. The RFSSW joint (welded at 600 rpm/3 s and refilled at 400 rpm/1 mm/min) showed a higher tensile shear load of 5400 N ± 100 compared with that recorded by the unrefilled joint (4300 N ± 80). The fracture location and fracture surface of the FSSW and RFSSW were examined and discussed.

14.
J Appl Stat ; 49(12): 2981-3001, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36035610

RESUMO

This paper deals with the statistical inference of the unknown parameters of three-parameter exponentiated power Lindley distribution under adaptive progressive type-II censored samples. The maximum likelihood estimator (MLE) cannot be expressed explicitly, hence approximate MLEs are conducted using the Newton-Raphson method. Bayesian estimation is studied and the Markov Chain Monte Carlo method is used for computing the Bayes estimation. For Bayesian estimation, we consider two loss functions, namely: squared error and linear exponential (LINEX) loss functions, furthermore, we perform asymptotic confidence intervals and the credible intervals for the unknown parameters. A comparison between Bayes estimation and the MLE is observed using simulation analysis and we perform an optimally criterion for some suggested censoring schemes by minimizing bias and mean square error for the point estimation of the parameters. Finally, a real data example is used for the illustration of the goodness of fit for this model.

15.
Materials (Basel) ; 15(9)2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35591306

RESUMO

Friction stir spot welding (FSSW) is one of the important variants of the friction stir welding (FSW) process. FSSW has been developed mainly for automotive applications where the different thickness sheets spot welding is essential. In the present work, different thin thickness sheets (1 mm and 2 mm) of AA6082-T6 were welded using FSSW at a constant dwell time of 3 s and different rotation speeds of 400, 600, 800, and 1000 rpm. The FSSW heat input was calculated, and the temperature cycle experience during the FSSW process was recorded. Both starting materials and produced FSSW joints were investigated by macro- and microstructural investigation, a hardness test, and a tensile shear test, and the fractured surfaces were examined using a scanning electron microscope (SEM). The macro examination showed that defect-free spot joints were produced at a wide range of rotation speeds (400-1000 rpm). The microstructural results in terms of grain refining of the stir zone (SZ) of the joints show good support for the mechanical properties of FSSW joints. It was found that the best welding condition was 600 rpm for achieving different thin sheet thicknesses spot joints with the SZ hardness of 95 ± 2 HV0.5 and a tensile shear load of 4300 ± 30 N.

16.
Artigo em Inglês | MEDLINE | ID: mdl-35524659

RESUMO

Background Artificial neural network (ANN) is an optimization method which is able to interact the input data and predict the best outputs. The ANN model determines the important factors affection the process. This could allow maximization of the process outputs. Objective There was only very limited publication on use of ANN for optimization of the bioprocess. This was a trial to use the model to optimize an extraction process and relate the extraction to the antimicrobial activities. Methods An artificial neural network as model was tested to optimize the extraction for clove flowers and relate it to the antimicrobial activities of the extracts. ANN model was constructed as by multilayer perception (MPL) with six input, two hidden layer and one output layer. The mean for the inhibition zone was 1.5 cm so the data categorized into two sets. Large inhibition zone > 1.5 - 2.3 cm and intermediate or small inhibition zone < 0.7-1.5 cm. The antimicrobial activities were tested against 20 microbial strains including 16 bacteria and 4 fungi. Six extraction method were performed and the resulted extracts were examined for their antimicrobial activities against 20 microbial strains which resulted in 120 readings. The statistical calculations for the model outputs were performed. The inhibition zones were taken as preliminary results for the model however the MIC was determined. Results The model shows an excellent performance with overall accurate prediction 86.6 %. According to the outputs from the model, the most important factor was the use of hot water as solvent for extraction. Calculation of the importance found the hot water important by about 100%. All statistical parameters like AUC, accumulation gain curve and lift chart for the model suggested that the model has an acceptable prediction efficiency. The AUC value was 0.91. GC-Mass was used to identify the most active constituent, it most cases 24 eugenol was identified as active ingredients and some other phenolic compounds. Conclusion According to the results and the statistical calculation for accuracy of the model it was apparent that the model can used successfully to predict and optimized the data for the extraction process. This could incite the ability of these models to be applied on similar processes. The model was efficient in prediction and determination the effective factors.

17.
J Basic Microbiol ; 62(3-4): 444-454, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34870865

RESUMO

Microbial detoxification of cyanide offered an inexpensive, safe, and viable alternative to physiochemical processes for the treatment of cyanide in industrial effluents or contaminated sites. This study involved isolation of novel strain with high resistance against cyanide toxicity and able to degrade the cyanide radical. The strain was isolated from rocky area and identified as Sphingobacterium multivorium using 16S ribosomal RNA. Resting pregrown cells were used in simple reaction mixture to avoid the complication associated with the media. One-gram fresh weight of this bacteria was able to remove 98.5% from 1.5 g/L cyanide which is a unique result. Factor affecting the biochemical process such as pH, temperature, agitation, glucose concentration was examined. The optimum conditions were, pH 6-7, 30-40°C, and 100-150 rpm shaking speed and 0.25% glucose. Furthermore, the cells were used after immobilization in polytetrafluoroethylene (PTFE) polymer. The PTFE is very safe carrier and the cells withstand the entrapment process and were able to remove 92% (1 g/L cyanide). The immobilized cells were used for six successive cycles with about 50% removal efficiency. The storage life extended to 14 days. No previous work studied the cyanide removal by Sphingobacterium spp. The strain showed good applicable characters.


Assuntos
Sphingobacterium , Células Imobilizadas/metabolismo , Cianetos/metabolismo , Concentração de Íons de Hidrogênio , Filogenia , Politetrafluoretileno , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sphingobacterium/genética , Sphingobacterium/metabolismo
18.
Anticancer Agents Med Chem ; 22(9): 1813-1825, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34431468

RESUMO

BACKGROUND: The marine algae are considered a diverse source of bioactive compounds. Many active compounds have been isolated from algae and show good biological activities. MATERIALS AND METHODS: The aim of this study is to detect the antiviral and anticancer activities in some extracts of marine algae. Extraction, purification and identification of some marine algae common in Egypt were conducted. Extraction of Ulva lactuca, Sargassum dentifolium, and Cystoseiara myrica was conducted. A sequence of extractions, including extraction by ethanol, boiling water, hydrochloric acid and sodium hydroxide were carried out. The obtained extracts were evaluated for their antitumour and antiviral activities against liver tumour cells, brain tumour cell lines, measles virus, mumps virus and hepatitis B virus (HBV). The extracts of the best activities were subjected for purification by size exclusion chromatography and anion exchange chromatography for ethanolic extracts or precipitation by cetylpyridinium chloride (CPC) then by size exclusion chromatography and anion exchange chromatography for aqueous extracts. Separation by GLS/MS was performed. The structures of the active compounds have been identified through different chemical analyses, including sugar analysis, configurational analysis, High-Performance Liquid Chromatography (HPLC), infrared spectroscopy (IR), Gas-Liquid Chromatography-Mass Spectroscopy (GLC-MS) and 1H,13C nuclear magnetic resonance (NMR) at ZV. RESULTS: The active compounds from the water extracts have been identified mainly as polysaccharides and sulphated polysaccharides. The antitumour and the antiviral activities of ethanolic extracts are attributable to compound identified as Ethyl Palmitate. These natural compounds did not show cytotoxic effect. CONCLUSION: These outputs could be preliminary for further biological studies aiming to therapeutic application.


Assuntos
Antivirais , Extratos Vegetais , Antivirais/farmacologia , Egito , Humanos , Extratos Vegetais/química , Polissacarídeos , Água
19.
Materials (Basel) ; 14(21)2021 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-34771883

RESUMO

Because of their great water repellency, Superhydrophobic coatings have a major impact on a variety of industrial applications. The current study's key originality is the development of low-cost, stable, superhydrophobic, and corrosion-resistant composite coatings. In the present work, polyvinylidene fluoride (PVDF)/Al2O3 composite coatings were produced using the spray technique to investigate the wettability and corrosion behavior of the coated materials for industrial and civil applications. PVDF was mixed with various concentrations of Al2O3 nanoparticles, and the mixture was sprayed onto steel, aluminum, and glass substrates. The wettability and morphology of the coated surfaces were investigated using the sessile droplet method and scanning electron microscopy, respectively. The corrosion resistance of bare substrates was compared to that of those coated with PVDF alone and those coated with PVDF/Al2O3 nanoparticles using Tafel polarization techniques. The force of adhesion between the coat and the substrates was measured in pounds per square inch. A nanoindentation test was also used to measure the hardness of the coating layer. The PVDF/Al2O3 coated steel showed a significantly higher water contact angle and lower contact angle hysteresis, reaching 157 ± 2° and 7 ± 1°, respectively, compared to the coated aluminum and glass substrates. Corrosion test results showed that the superhydrophobic PVDF/Al2O3 coatings had a much higher corrosion protection efficiency for steel and aluminum than that of the PVDF ones. The PVDF/Al2O3 coated substrates showed moderate but still acceptable adhesion between the coating layer and the substrates. Moreover, the PVDF/Al2O3 coatings had much better mechanical properties than the PVDF only coatings. Such type of coating could be a promising candidate for possible industrial and civil applications.

20.
PLoS One ; 16(2): e0246969, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33606720

RESUMO

Lifetime distributions are an important statistical tools to model the different characteristics of lifetime data sets. The statistical literature contains very sophisticated distributions to analyze these kind of data sets. However, these distributions have many parameters which cause a problem in estimation step. To open a new opportunity in modeling these kind of data sets, we propose a new extension of half-logistic distribution by using the odd Lindley-G family of distributions. The proposed distribution has only one parameter and simple mathematical forms. The statistical properties of the proposed distributions, including complete and incomplete moments, quantile function and Rényi entropy, are studied in detail. The unknown model parameter is estimated by using the different estimation methods, namely, maximum likelihood, least square, weighted least square and Cramer-von Mises. The extensive simulation study is given to compare the finite sample performance of parameter estimation methods based on the complete and progressive Type-II censored samples. Additionally, a new log-location-scale regression model is introduced based on a new distribution. The residual analysis of a new regression model is given comprehensively. To convince the readers in favour of the proposed distribution, three real data sets are analyzed and compared with competitive models. Empirical findings show that the proposed one-parameter lifetime distribution produces better results than the other extensions of half-logistic distribution.


Assuntos
Modelos Estatísticos , Funções Verossimilhança , Análise de Regressão
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