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1.
Cancer ; 2024 May 20.
Article in English | MEDLINE | ID: mdl-38768296

ABSTRACT

BACKGROUND: Patients with relapsed primary mediastinal nonseminomatous germ cell tumor have low cure rates with salvage chemotherapy or surgery. The authors report survival outcomes of patients who received high-dose chemotherapy (HDCT) and peripheral blood stem cell transplantation (PBSCT) at Indiana University. METHODS: The prospectively maintained Indiana University germ cell tumor database identified 32 patients with primary mediastinal nonseminomatous germ cell tumor who progressed after first-line cisplatin-based combination chemotherapy and received HDCT and PBSCT between 2006 and 2021. Therapy included two consecutive courses of HDCT consisting of 700 mg/m2 carboplatin and 750 mg/m2 etoposide, each for 3 consecutive days, and each followed by PBSCT. A second course was not given if the patient experienced progressive disease or prohibitive toxicity. Progression-free survival and overall survival were analyzed using the Kaplan-Meier method. Medians with 95% confidence intervals were also calculated along with 2-year probabilities. RESULTS: The median age at HDCT was 30 years (range, 18-61 years). With a median follow-up of 4.7 years (range, 1-14 years), the 2-year progression-free survival rate was 31% (95% confidence interval, 16%-47%), and the 2-year overall survival rate was 35% (95% confidence interval, 19%-52%). At last follow-up, nine patients (28%) remained without evidence of disease, including two platinum-refractory patients and two patients who were receiving HDCT as third-line therapy. There were three treatment-related deaths. CONCLUSIONS: Salvage HDCT and PBSCT is an active combination in patients who have relapsed primary mediastinal nonseminomatous germ cell tumor with curative potential and prolonged survival, including in platinum-refractory and third-line settings. The authors recommend this approach for initial salvage chemotherapy in this patient population.

2.
Eur Rev Med Pharmacol Sci ; 27(20): 9628-9638, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37916328

ABSTRACT

OBJECTIVE: This study aimed to investigate the effect of adhesive thinning on resin-dentin-bonded interfaces created by two simplified adhesives. MATERIALS AND METHODS: Micro-tensile bond strengths and interfacial nanoleakage were evaluated within bonded dentin interfaces formed by Adper Single Bond 2 and Single Bond Universal after 24 hours and 6 months of water storage. The adhesives were subjected to three different techniques: air-thinning, brush-thinning, or application without thinning. Statistical analysis was performed using a multi-level analysis of variance followed by Bonferroni's post-hoc test, at a significance level of 0.05. RESULTS: Adper Single Bond 2 demonstrated the highest immediate microtensile bond strengths (43.5 ± 1.3 MPa) and the lowest immediate nanoleakage (49.8 ± 2.8%) when air-thinning was employed. Single Bond Universal exhibited the lowest nanoleakage (36.4 ± 1.8%) when air-thinning was used, although there was no significant difference in immediate bond strengths between air-thinning and brush-thinning approaches, which both showed higher values compared to the no-thinning approach. After 6 months of storage, a significant decrease in bond strengths and a significant increase in nanoleakage were observed across most groups (p < 0.001). CONCLUSIONS: While all groups displayed varying degrees of instability over a 6-month storage period, air-thinning of simplified etch-and-rinse and self-etch adhesives proved to provide clinically acceptable bonded interfaces. The findings suggest that adhesive thinning techniques can play a vital role in enhancing bond stability and longevity in resin-dentin-bonded interfaces.


Subject(s)
Dentin , Resin Cements , Adhesives , Dentin-Bonding Agents/chemistry , Materials Testing
3.
Niger J Clin Pract ; 25(1): 78-84, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35046199

ABSTRACT

BACKGROUND: Cancer is a major public health problem and is the second leading cause of death around the world. The incidence rates of some cancer types rise dramatically with certain risk factors, a fact that is exemplified by the high susceptibility to lung cancer as a result of tobacco smoking. The frame of cancer as a preventable disease and the challenges of its treatment emphasize the need for specific risk preventive measures. Therefore, attempts are continuously carried out to provide a better understanding of the cancer incidence patterns and how the most common risk factors are implicated. AIMS: This study aimed to compare the cancer incidence rates in Jordan, Lebanon, Palestine, Syria, and Iraq over 18 years (2000-2017) and relate the high estimates to certain risk factors to help decision-makers better prevent this disease. MATERIALS AND METHODS: Graphical and numerical descriptive illustrations of the total incidence rates, age-specific incidence rates, and incidence by cancer type were generated using data obtained from the Global Health Data exchange database. Risk factors prevalence and their pathogenic role were sought using PubMed and science direct databases as well as the world bank data. RESULTS: Lebanon had the highest overall age-adjusted incidence rates with a gradual increase from 231 to 353 and the highest life expectancy mean of 77.5 years. Breast, lung, and colorectal cancers were the most common cancer types in both genders and all ages in the five countries with varied ratios that were consistent with the risk factors prevalent. CONCLUSIONS: The association between the spread of the studied risk factors and the high trends of the corresponding cancer types highlights the importance of targeted preventive measures and serve as a guide for evidence-based prevention strategies.


Subject(s)
Life Expectancy , Lung Neoplasms , Aged , Female , Humans , Incidence , Male , Mediterranean Region , Risk Factors
4.
J Appl Microbiol ; 131(4): 1621-1638, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33386652

ABSTRACT

The discharge of the toxic phenol-polluted petro-industrial effluents (PPPIE) has severe environmental negative impacts, thus it is mandatory to be treated before its discharge. The objective of this review was to discuss the sustainable application of microalgae in phenols degradation, with a special emphasis on the enzymes involved in this bioprocess and the factors affecting the success of PPPIE phycoremediation. Moreover, it confers the microalgae bioenergetic strategies to degrade different forms of phenols in PPPIE. It also points out the advantages of the latest application of bacteria, fungi and microalgae as microbial consortia in phenols biodegradation. Briefly, phycoremediation of PPPIE consumes carbon dioxide emitted from petro-industries for; valorization of the polluted water to be reused and production of algal biomass which can act as a source of energy for such integrated bioprocess. Besides, the harvested algal biomass can feasibly produce; third-generation biofuels, biorefineries, bioplastics, fish and animal feed, food supplements, natural dyes, antioxidants and many other valuable products. Consequently, this review precisely confirms that the phycoremediation of PPPIE is a win-win process for a green environment and a sustainable future. Thus, to achieve the three pillars of sustainability; social, environmental and economic; it is recommendable to integrate PPPIE treatment with algal cultivation. This integrated process would overcome the problem of greenhouse gas emissions, global warming and climate change, solve the problem of water-scarce, and protect the environment from the harmful negative impacts of PPPIE.


Subject(s)
Microalgae , Phenol , Animals , Biofuels , Biomass , Phenols , Wastewater
5.
J Appl Microbiol ; 129(2): 319-334, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32118335

ABSTRACT

AIMS: This research was conducted to investigate the biocatalytic remediation of xenobiotics polluted seawater using two biocatalysts; whole bacterial cells of facultative aerobic halotolerant Corynebacterium variabilis Sh42 and its extracted crude enzymes. METHODS AND RESULTS: One-Factor-at-A-Time technique and statistical analysis were applied to study the effect of initial substrate concentrations, pH, temperature, and initial biocatalyst concentrations on the batch biocatalytic degradation of three xenobiotic pollutants (2-hydroxybiphenyl (2-HBP), catechol and benzoic acid) in artificial seawater (salinity 3·1%). HPLC and gas-chromatography mass spectroscopy analyses were utilized to illustrate the quantitative removal of the studied aromatic xenobiotic pollutants and their catabolic pathway. The results revealed that the microbial and enzymatic cultures followed substrate inhibition kinetics. Yano and Koga's equation showed the best fit for the biokinetic degradation rates of 2-HBP and benzoic acid, whereas Haldane biokinetic model adequately expressed the specific biodegradation rate of catechol. The biokinetic results indicated the good efficiency and tolerance of crude enzyme for biocatalytic degradation of extremely high concentrations of aromatic pollutants than whole C. variabilis Sh42 cells. The monitored by-products indicated that the catabolic degradation pathway followed an oxidation mechanism via a site-specific monooxygenase enzyme. Benzoic acid and catechol were identified as major intermediates in the biodegradation pathway of 2-HBP, which were then biodegraded through meta-cleavage to 2-hydroxymuconic semialdehyde. With time elapsed, the semialdehyde product was further biodegraded to acetaldehyde and pyruvic acid, which would be further metabolized via the bacterial TCA cycle. CONCLUSION: The batch enzymatic bioreactors performed superior-specific biocatalytic degradation rates for all the studied xenobiotic pollutants. SIGNIFICANCE AND IMPACT OF THE STUDY: The enzymatic system of C. variabilis Sh42 is tolerable for toxic xenobiotics and different physicochemical environmental parameters. Thus, it can be recommended as an effective biocatalyst for biocatalytic remediation of xenobiotics polluted seawater.


Subject(s)
Seawater/chemistry , Water Pollutants, Chemical/metabolism , Xenobiotics/metabolism , Biocatalysis , Biodegradation, Environmental , Bioreactors , Corynebacterium/metabolism , Kinetics , Metabolic Networks and Pathways
6.
Phys Rev Lett ; 124(8): 084301, 2020 Feb 28.
Article in English | MEDLINE | ID: mdl-32167332

ABSTRACT

Rotationally resonant metamaterials are leveraged to answer a longstanding question regarding the existence of transformation-invariant elastic materials and the ad hoc possibility of transformation-based passive cloaking in full plane elastodynamics. Combined with tailored lattice geometries, rotational resonance is found to induce a polar and chiral behavior, that is, a behavior lacking stress and mirror symmetries, respectively. The central, and simple, idea is that a population of rotating resonators can exert a density of body torques strong enough to modify the balance of angular momentum on which hang these symmetries. The obtained polar metamaterials are used as building blocks of a cloaking device. Numerical tests show satisfactory cloaking performance under pressure and shear probing waves, further coupled through a free boundary. The work sheds new light on the phenomenon of resonance in metamaterials and should help put transformation elastodynamics on equal footing with transformation acoustics and optics.

7.
J Appl Microbiol ; 128(2): 438-457, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31650655

ABSTRACT

AIMS: Investigate the capability of Aspergillus brasiliensis ATCC 16404 to mycosynthesize Co3 O4 -NPs. METHODS AND RESULTS: Mycelial cell-free filtrate of A. brasiliensis ATCC 16404 was applied for mycosynthesis of Co3 O4 -NPs. The preliminary indication for the formation of Co3 O4 -NPs was the change in colour from yellow to reddish-brown. One-factor-at a time-optimization technique was applied to determine the optimum physicochemical conditions required for the mycosynthesis of Co3 O4 -NPs and they were found to be: 72 h for reaction time, pH 11, 30°C, 100 rev min-1 for shaking speed in the darkness using 4 mmol l-1 of CoSO4. 7H2 O and 5·5% of A. brasiliensis dry weight mycelium (w/v). The mycosynthesized Co3 O4 -NPs were characterized using various techniques: spectroscopy including UV/Vis spectrophotometry, dynamic light scattering (DLS), zeta potential measurement, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy and X-ray diffraction; and vibrating sample magnetometry and microscopy including field emission scanning electron microscopy and high-resolution transmission electron microscopy. Spectroscopic techniques confirmed the formation of Co3 O4 -NPs and the microscopic ones confirmed the shape and size of the mycosynthesized Co3 O4 -NPs as quasi-spherical shaped, monodispersed nanoparticles with a nano size range of 20-27 nm. The mycosynthesized Co3 O4 -NPs have excellent magnetic properties and exhibited a good antimicrobial activity against some pathogenic micro-organisms. CONCLUSION: Ferromagnetic Co3 O4 -NPs with considerable antimicrobial activity were for the first time mycosynthesized. SIGNIFICANCE AND IMPACT OF THE STUDY: The use of fungi as potential bionanofactories for mycosynthesis of nanoparticles is relatively a recent field of research with considerable prospects.


Subject(s)
Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Aspergillus/drug effects , Cobalt/chemistry , Cobalt/pharmacology , Metal Nanoparticles/chemistry , Metal Nanoparticles/toxicity , Oxides/chemistry , Oxides/pharmacology , Antifungal Agents/chemical synthesis , Aspergillus/growth & development , Magnetics , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction
8.
Epidemiol Infect ; 147: e276, 2019 09 25.
Article in English | MEDLINE | ID: mdl-31552815

ABSTRACT

We examined the prevalence and correlates of Helicobacter pylori (H. pylori) infection according to cytotoxin-associated gene A (CagA) phenotype, a main virulence antigen, among the ethnically diverse population groups of Jerusalem. A cross-sectional study was undertaken in Arab (N = 959) and Jewish (N = 692) adults, randomly selected from Israel's national population registry in age-sex and population strata. Sera were tested for H. pylori immunoglobulin G (IgG) antibodies. Positive samples were tested for virulence IgG antibodies to recombinant CagA protein, by enzyme-linked immunosorbent assay. Multinomial regression models were fitted to examine associations of sociodemographic factors with H. pylori phenotypes. H. pylori IgG antibody sero-prevalence was 83.3% (95% confidence interval (CI) 80.0%-85.5%) and 61.4% (95% CI 57.7%-65.0%) among Arabs and Jews, respectively. Among H. pylori positives, the respective CagA IgG antibody sero-positivity was 42.3% (95% CI 38.9%-45.8%) and 32.5% (95% CI 28.2%-37.1%). Among Jews, being born in the Former Soviet Union, the Middle East and North Africa, vs. Israel and the Americas, was positively associated with CagA sero-positivity. In both populations, sibship size was positively associated with both CagA positive and negative phenotypes; and education was inversely associated. In conclusion, CagA positive and negative infection had similar correlates, suggesting shared sources of these two H. pylori phenotypes.


Subject(s)
Antigens, Bacterial/immunology , Bacterial Proteins/immunology , Helicobacter Infections/epidemiology , Helicobacter pylori/immunology , Virulence Factors/immunology , Adult , Aged , Antibodies, Bacterial/blood , Arabs , Cross-Sectional Studies , Demography , Female , Helicobacter Infections/microbiology , Humans , Immunoglobulin G/blood , Israel/epidemiology , Jews , Male , Middle Aged , Seroepidemiologic Studies , Socioeconomic Factors
9.
J Appl Microbiol ; 126(1): 138-154, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30199141

ABSTRACT

AIMS: In order to efficiently control the corrosive sulphate-reducing bacteria (SRB), the main precursor of the microbial influenced corrosion (MIC) in oil industry, the ability of Trichoderma longibrachiatumDSMZ 16517 to synthesize silver nanoparticles (AgNPs) was investigated and their biocidal activity against halotolerant SRB was tested. METHODS AND RESULTS: The mycelial cell-free filtrate (MCFF) bioreduced the silver ions (Ag+ ) to their metallic nanoparticle state (Ag0 ), which was presumptively indicated by the appearance of a dark brown suspension and confirmed by the characteristic absorbance of AgNPs at ʎ422nm . One-factor-at-a-time technique was used to optimize the effect of temperature, time, pH, fungal biomass and silver nitrate concentrations, stirring rates and dark effect. The dynamic light scattering (DLS) analysis revealed average AgNPs size and zeta potential values of 17·75 nm and -26·8 mV, respectively, indicating the stability of the prepared AgNPs. The X-ray diffraction (XRD) pattern assured the crystallinity of the mycosynthesized AgNPs, with an average size of 61 nm. The field emission scanning electron microscope (FESEM) and high-resolution transmission electron microscope (HRTEM) showed nonagglomerated spherical, triangular and cuboid AgNPs ranging from 5 to 11 ± 0·5 nm. The Fourier transform infrared spectroscopy (FT-IR) analysis of the mycosynthesized AgNPs affirmed the role of MCFF as a reducing and capping agent. A preliminary suggested mechanism for mycosynthesis of AgNPs was elucidated. The mycosynthesized AgNPs expressed high biocidal activity against a halotolerant planktonic mixed culture of SRB. The HRTEM analysis showed a clear evidence of an alteration in cell morphology, a disruption of SRB cell membranes, a lysis in cell wall and a cytoplasmic extraction after treatment with AgNPs. This confirmed the bactericidal effect of the mycosynthesized AgNPs. CONCLUSION: The biocidal activity of the mycosynthesized AgNPs against halotolerant planktonic SRB makes it an attractive option to control MIC in the petroleum industry. SIGNIFICANCE AND IMPACT OF THE STUDY: This research provides a helpful insight into the development of a new mycosynthesized biocidal agent against the corrosive sulphate-reducing bacteria.


Subject(s)
Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Metal Nanoparticles/chemistry , Silver/metabolism , Silver/pharmacology , Sulfates/metabolism , Trichoderma/metabolism , Anti-Bacterial Agents/chemistry , Bacteria/metabolism , Microscopy, Electron, Transmission , Oxidation-Reduction , Silver/chemistry , Sodium Chloride/metabolism , Spectroscopy, Fourier Transform Infrared , Trichoderma/chemistry , Trichoderma/genetics , X-Ray Diffraction
10.
J Clin Oncol ; 36(29): 2950-2954, 2018 10 10.
Article in English | MEDLINE | ID: mdl-30156983

ABSTRACT

PURPOSE: Three cycles of bleomycin, etoposide, and cisplatin (BEP × 3) or four cycles of etoposide and cisplatin (EP × 4) are first-line chemotherapy regimens for men with International Germ Cell Cancer Collaborative Group (IGCCCG) good-risk germ cell tumors (GCTs). We determined whether inclusion of bleomycin affected pulmonary and operative morbidity after postchemotherapy retroperitoneal lymph node dissection (PC-RPLND). PATIENTS AND METHODS: We queried our database to identify IGCCCG good-risk patients who received BEP × 3 or EP × 4 induction chemotherapy before PC-RPLND from 2006 to 2016. Patients who received combination regimens were excluded. The primary outcomes of interest were pulmonary morbidity (prolonged intubation, reintubation, supplemental oxygen use, intensive care unit stay) and operative morbidity (operative time, length of stay, concomitant procedures, estimated blood loss). RESULTS: We analyzed 234 patients (191 BEP × 3 v 43 EP × 4). All patients were extubated immediately after the operation. None were reintubated or discharged on oxygen. Two patients in each cohort required an intensive care unit stay for nonpulmonary reasons. Patients treated with BEP required shorter use of supplemental oxygen (0.99 v 1.63 days; P = .005). No significant differences were found in preoperative mass size ( P = .42) or concomitant surgeries ( P = .58). Operative time was significantly shorter (131 v 170 minutes; P < .01), and estimated blood loss was considerably less (194 v 226 mL; P < .01) in patients treated with BEP. Length of stay was shorter in patients treated with BEP (3.3 v 3.9 days; P < .01). CONCLUSION: In a modern surgical cohort, the inclusion of bleomycin does not seem to influence pulmonary morbidity, operative difficulty, or nonpulmonary postoperative complications after PC-RPLND in men with IGCCCG good-risk GST.


Subject(s)
Antibiotics, Antineoplastic/adverse effects , Bleomycin/adverse effects , Lymph Node Excision/methods , Neoplasms, Germ Cell and Embryonal/drug therapy , Testicular Neoplasms/drug therapy , Adult , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bleomycin/administration & dosage , Cisplatin/administration & dosage , Etoposide/administration & dosage , Humans , Length of Stay/statistics & numerical data , Lung/drug effects , Male , Neoplasms, Germ Cell and Embryonal/surgery , Operative Time , Postoperative Hemorrhage , Retroperitoneal Space , Testicular Neoplasms/surgery , Young Adult
11.
J Appl Microbiol ; 125(2): 370-382, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29624805

ABSTRACT

AIMS: Since mycosynthesis of metal nanoparticles (NPs) is advertised as a promising and ecofriendly approach. Thus, this study aims to investigate the capability of Aspergillus brasiliensis ATCC 16404 for mycosynthesis of silver NPs (AgNPs). METHODS AND RESULTS: One-factor-at-a-time-technique was used to study the effect of different physicochemical parameters: the reaction time, pH, temperature, different stirring rates, illumination, and finally, the different concentrations of silver nitrate and fungal biomass on the mycosynthesis of AgNPs. The visual observation showed the characteristic brown colour formation due to the bioreduction of Ag+ ions to Ag0 by the mycelial cell-free filtrate (MCFF). The UV/visible spectrophotometric technique displayed a characteristic sharp peak at ʎ440 confirming the mycosynthesis of AgNPs. The zeta potential value -16·7 mV assured the long-term stability of AgNPs and the dynamic light scattering analysis revealed good dispersion and average particle size 77 nm. The energy dispersive X-ray spectroscopy displayed a maximum elemental distribution of silver elements. The X-ray diffraction spectroscopy demonstrated the crystallinity of the mycosynthesized AgNPs. The field emission scanning electron microscope and high-resolution transmission electron microscope revealed monodispersed spherical shaped AgNPs with average particle size of 6-21 nm. The FTIR analysis showed the major peaks of proteins providing the possible role of MCFF in the synthesis and stabilization of the AgNPs. The mycosynthesized AgNPs expressed good biocidal activity against different pathogenic micro-organisms causing some water-related diseases and health problems to local residents. CONCLUSIONS: This study proved that A. brasiliensis ATCC 16404 MCFF has good potential for mycosynthesis of AgNPs, which exhibited good antimicrobial effect on different pathogenic micro-organisms; thus, it can be applied for water disinfection. SIGNIFICANCE AND IMPACT OF THE STUDY: This research provides a helpful insight into the development of a new mycosynthesized antimicrobial agent.


Subject(s)
Anti-Bacterial Agents/pharmacology , Aspergillus/metabolism , Metal Nanoparticles/chemistry , Silver/pharmacology , Anti-Bacterial Agents/chemistry , Drug Stability , Metal Nanoparticles/ultrastructure , Microbial Sensitivity Tests , Particle Size , Silver/chemistry , Surface Properties
12.
Eur J Dent Educ ; 22(3): 192-197, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29227014

ABSTRACT

PURPOSE: The weighted mean (WM) method for combining scores of assessment components can provide outcomes with biased reliability and score precision. The objective of this study was to compare the traditional WM with another method utilising the composite score (CS) principle for combining scores of a final summative assessment exercise for a pre-clinical dental course. METHODS: Data were collected from the final examination of third-year Preclinical Operative and Esthetic Dentistry course consisting of 3 parts: practical competency, objective structured practical examination and a written examination with weights of 33%, 17% and 50%, respectively. Scores from the 3 components were combined using the WM and CS methods. Weighted kappa was used to compare both approaches for agreement, and students' ranks were also compared. RESULTS: Combining scores using CS scheme produced lower scores overall compared to WM with more apparent effect for the male group. Agreement between WM and CS was moderate (κ = 0.44) with major differences between students' ranks across the 2 modalities as only 21% of the cohort retained their ranks. CONCLUSION: The CS method produced more reliable scores, resulting in moderate agreement with the WM and major shift in students' ranks. These findings necessitate further validity considerations before implementing the CS method and call for further studies that examine the consequences of composite measures in dental education.


Subject(s)
Clinical Competence/statistics & numerical data , Education, Dental , Educational Measurement/methods , Students, Dental , Esthetics, Dental , Humans , Reproducibility of Results
13.
Proc Math Phys Eng Sci ; 473(2202): 20170188, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28690416

ABSTRACT

Time-reversal symmetry for elastic wave propagation breaks down in a resonant mass-in-mass lattice whose inner-stiffness is weakly modulated in space and in time in a wave-like fashion. Specifically, one-way wave transmission, conversion and amplification as well as unidirectional wave blocking are demonstrated analytically through an asymptotic analysis based on coupled mode theory and numerically thanks to a series of simulations in harmonic and transient regimes. High-amplitude modulations are then explored in the homogenization limit where a non-standard effective mass operator is recovered and shown to take negative values over unusually large frequency bands. These modulated metamaterials, which exhibit either non-reciprocal behaviours or non-standard effective mass operators, offer promise for applications in the field of elastic wave control in general and in one-way conversion/amplification in particular.

14.
Proc Math Phys Eng Sci ; 473(2197): 20160705, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28265194

ABSTRACT

Origami tessellations are particular textured morphing shell structures. Their unique folding and unfolding mechanisms on a local scale aggregate and bring on large changes in shape, curvature and elongation on a global scale. The existence of these global deformation modes allows for origami tessellations to fit non-trivial surfaces thus inspiring applications across a wide range of domains including structural engineering, architectural design and aerospace engineering. The present paper suggests a homogenization-type two-scale asymptotic method which, combined with standard tools from differential geometry of surfaces, yields a macroscopic continuous characterization of the global deformation modes of origami tessellations and other similar periodic pin-jointed trusses. The outcome of the method is a set of nonlinear differential equations governing the parametrization, metric and curvature of surfaces that the initially discrete structure can fit. The theory is presented through a case study of a fairly generic example: the eggbox pattern. The proposed continuous model predicts correctly the existence of various fittings that are subsequently constructed and illustrated.

15.
Anaesthesia ; 71(10): 1177-85, 2016 10.
Article in English | MEDLINE | ID: mdl-27611039

ABSTRACT

This randomised, controlled, double-blind study investigated the effects of different doses of perineural dexmedetomidine on the pharmacodynamic profile of femoral nerve block in patients undergoing arthroscopic knee surgery. Ultrasound-guided femoral nerve block was performed before general anaesthesia using 25 ml of bupivacaine 0.5% combined with normal saline in the control group, and 25 µg, 50 µg or 75 µg of dexmedetomidine in three treatment groups (n = 15 for each group). All patients received a standard general anaesthetic and multimodal postoperative analgesic regimen. The use of the 50 µg and 75 µg dose levels of dexmedetomidine was associated with reduction of the onset time, extension of the duration of block, prolonged time to the first postoperative request for rescue analgesia, and reduced postoperative morphine requirements. The times to first request for postoperative analgesia were mean (SD) 10.8 (1.6) h in the control group and 11.0 (7.1), 21.8 (3.0) and 28.6 (10.0) in the 25 µg, 50 µg and 75 µg treatment groups, respectively. These times were significantly longer in the 50 µg and 75 µg treatment groups compared with the 25 µg (p < 0.0001) and control group (p < 0.0001). The total 24-h postoperative morphine consumption was 7.6 (5.1) mg in the control group, and 6.5 (3.5), 3.9 (3.4), 1.8 (2.6) in the 25 µg, 50 µg and 75 µg treatment groups, respectively. Postoperative morphine consumption was significantly higher in the control group compared with the 50 µg (p = 0.045) and the 75 µg (p = 0.001) treatment groups. The best analgesic profile was achieved at the 75 µg dose, but this was associated with increased risk of hypotension.


Subject(s)
Arthroscopy , Bupivacaine/pharmacology , Dexmedetomidine/pharmacology , Knee Joint/surgery , Nerve Block/methods , Adolescent , Adult , Anesthetics, Local/pharmacology , Dose-Response Relationship, Drug , Double-Blind Method , Drug Therapy, Combination , Female , Femoral Nerve/drug effects , Humans , Hypnotics and Sedatives/pharmacology , Male , Middle Aged , Ultrasonography, Interventional , Young Adult
16.
Clin Chim Acta ; 445: 41-7, 2015 May 20.
Article in English | MEDLINE | ID: mdl-25801214

ABSTRACT

BACKGROUND: Recent studies showing that high density lipoproteins (HDL) can effect plaque regression indicate that recent trial failures do not exclude an atheroprotective role of HDL. Instead, they highlight differences between HDL function and measured HDL-cholesterol (HDL-C). PON1 is one key functional activity of HDL. Urban Palestinians have lower HDL-C and a higher incidence and mortality of coronary heart disease than those of Israelis. We hypothesized that the cardioprotective PON1 lactonase and arylesterase activities and PON1 functional genotype may differ between Palestinians and Israelis. METHODS: We measured PON1 activities in a cross-sectional population-based study of Palestinian (n=960) and Israeli (n=694) residents in Jerusalem, 1654 participants in all. RESULTS: Palestinians had high prevalences of obesity and diabetes and low mean concentrations of HDL-cholesterol (0.97 mmol/l in men and 1.19 mmol/l in women). Lactonase and arylesterase activities were lower by 10.8% (p=1.2∗10(-14)) and 2.7% (p<0.0005), respectively, in Palestinians as compared to Israelis. The functional genotype distribution, demonstrated by plotting paraoxonase vs lactonase activities, showed a modest between-group difference (p=0.024), with 12.1% RR in Palestinian Arabs vs 8.4% in Israeli Jews, but no overall difference in allele frequencies. Lactonase correlated inversely with age (Spearman's rho=-.156), weakly with BMI (-.059), positively with HDL-C (.173) and non-HDL-C (.103), but was not associated with triglycerides or fasting glucose. Palestinians showed consistently lower lactonase activity in logistic regression models adjusted for multiple covariates and for functional genotype (odds ratios of 1.81 and 1.98, respectively, for the lower fifth vs the upper 4 fifths of lactonase activity p<0.0001). CONCLUSION: We showed a lower physiologically-significant lactonase PON1 activity in an Arab population, a finding consistent with the high cardiovascular and diabetes risk of Palestinians.


Subject(s)
Aryldialkylphosphatase/genetics , Carboxylic Ester Hydrolases/genetics , Cholesterol, HDL/blood , Coronary Disease/genetics , Diabetes Mellitus/genetics , Obesity/genetics , Adult , Age Factors , Aged , Alleles , Arabs , Aryldialkylphosphatase/metabolism , Blood Glucose/metabolism , Carboxylic Ester Hydrolases/metabolism , Cholesterol, HDL/genetics , Coronary Disease/diagnosis , Coronary Disease/enzymology , Coronary Disease/ethnology , Cross-Sectional Studies , Diabetes Mellitus/diagnosis , Diabetes Mellitus/enzymology , Diabetes Mellitus/ethnology , Female , Gene Expression , Gene Frequency , Genotype , Humans , Israel/epidemiology , Jews , Male , Middle Aged , Obesity/diagnosis , Obesity/enzymology , Obesity/ethnology , Prevalence , Risk Factors , Triglycerides/blood
17.
Z Rheumatol ; 74(6): 529-32, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25098691

ABSTRACT

AIM OF THE WORK: To detect the incidence of premature atherosclerosis in systemic lupus erythematosus (SLE) patients and to study its association with disease activity and damage indices. PATIENTS AND METHODS: This study involved 50 adult female SLE patients with mean age 26.24 ± 8.63 years and mean disease duration 3.44 ± 4.01 years. The control group comprised 25 healthy adult females. All patients were subjected to a detailed clinical examination and laboratory investigations, and full case history was recorded. Assessment of disease activity was performed according to the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and disease damage was assessed using the Systemic Lupus International Collaborating Clinics (SLICC) score. B mode ultrasound was used to measure the intima-media wall thickness (IMT) and detect the presence of carotid plaques. RESULTS: In 15 patients (30 %), positive ultrasonographic findings represented by a significant increase in IMT (> 0.9 mm) could be shown; plaques were found in 3 of these patients (6 %). A significant difference was found between SLE patients and controls in terms of IMT (P < 0.0001). On subgrouping the SLE patients according to their IMT, there was a significant difference between those with thickened and normal IMT in terms of SLEDAI (P < 0.0001) and SLICC (p = 0.035) scores. CONCLUSION: Subclinical atherosclerosis is frequent in SLE patients. Increased disease activity and damage are associated with the occurrence of premature atherosclerosis.


Subject(s)
Carotid Artery Diseases/diagnostic imaging , Carotid Artery Diseases/etiology , Lupus Erythematosus, Systemic/complications , Lupus Erythematosus, Systemic/diagnosis , Adult , Asymptomatic Diseases , Female , Humans , Reproducibility of Results , Sensitivity and Specificity , Severity of Illness Index , Ultrasonography
18.
Radiat Prot Dosimetry ; 150(4): 434-40, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22232779

ABSTRACT

Building regulations in Israel require the insulating of buildings against radon (222)Rn penetration from soil. In radon-prone areas membranes stretched between the soil and the building foundation are used, together with sealing other possible penetration routes. Designing the radon mitigation procedure requires checking that all sealing materials are practically, radon tight, having a thickness of at least three times the radon diffusion length. In this work, a very simple technique to evaluate the radon diffusion length in thin membranes, using a radon source of known activity and an activated charcoal canister as radon detector is presented. The theoretical formalism and measurement results for polyethylene membranes of different densities obtained in a recent comparison exercise are presented.


Subject(s)
Air Pollutants, Radioactive/chemistry , Air Pollution, Indoor/analysis , Membranes, Artificial , Polyethylene/chemistry , Radon/chemistry , Construction Materials , Diffusion , Materials Testing
19.
J Int Med Res ; 39(4): 1123-41, 2011.
Article in English | MEDLINE | ID: mdl-21986115

ABSTRACT

The findings of an expert panel convened to review critically how best to apply evidence-based guidelines for the treatment of acute pain in the Middle East region are presented. The panel recommended a three-step treatment protocol. Patients with mild-to-moderate levels of acute pain should be treated with paracetamol (step 1). If analgesia is insufficient after 1-2 days, a selective cyclo-oxygenase-2 inhibitor or, if gastrointestinal safety and bleeding risk are not an issue, a non-specific nonsteroidal anti-inflammatory drug, should be used (step 2). If analgesia remains inadequate, treatment with tramadol, or paracetamol plus codeine/tramadol is recommended (step 3). Patients reporting severe pain should be referred to a pain clinic or specialist for opioid analgesic treatment. Measures of pain and functioning that have been validated in Arabic, with culturally appropriate and easy to understand descriptors, should be used. Early and aggressive acute pain management is important to reduce the risk of pain becoming chronic, especially in the presence of neuropathic features.


Subject(s)
Acute Pain/drug therapy , Analgesics, Opioid/therapeutic use , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Practice Guidelines as Topic/standards , Clinical Trials as Topic , Consensus , Humans , Middle East , Pain Measurement
20.
Caries Res ; 45(4): 346-52, 2011.
Article in English | MEDLINE | ID: mdl-21778722

ABSTRACT

OBJECTIVE: To investigate how the size of the space between restoration and dentinal wall of the tooth affects the development of secondary caries lesions, especially wall lesions. METHODS: Tooth-resin composite specimens were mounted on custom-made gap model stages and divided into 4 groups (n = 10): group 1 with a 30-µm gap throughout both enamel and dentin, group 2 with a 30-µm enamel gap and 530-µm dentinal gap, group 3 with 525-µm gaps in both enamel and dentin, and group 4 with 525-µm and 1,025-µm gaps in enamel and dentin, respectively. Specimens were gas sterilized and incubated in a cycling microbial caries model for 8 days and analyzed with confocal microscopy for lesion size at the enamel outer lesion (EOL), enamel wall lesion (EWL), dentin wall lesion A (DWL-A) next to the dentin-enamel junction (DEJ) and dentin wall lesion B (DWL-B) at 750 µm from the DEJ. RESULTS: No difference in EOL or EWL size was found between the groups. DWL-A and DWL-B were larger in group 3 than groups 1 and 2. A larger DWL-B was found in group 3 than group 4. CONCLUSIONS: The presence of additional space at the dentinal wall area did not affect secondary caries development as long as the enamel gap was small. However, with enamel gaps of approximately 500 µm, the presence of the additional gap space at the dentinal wall led to the development of smaller dentinal wall lesions at the deeper parts of the simulated cavity. In uniform gaps, the size of the interface was positively correlated with the size of the dentinal wall lesions.


Subject(s)
Dental Caries/etiology , Dental Caries/therapy , Dental Marginal Adaptation , Dental Restoration, Permanent/methods , Analysis of Variance , Composite Resins , Dental Enamel , Dental Leakage/complications , Dentin , Humans , Microscopy, Confocal , Models, Biological , Recurrence , Statistics, Nonparametric , Streptococcus mutans
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