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1.
Isr Med Assoc J ; 20(5): 291-294, 2018 05.
Article in English | MEDLINE | ID: mdl-29761674

ABSTRACT

BACKGROUND: The recommendation of the U.S. Centers for Disease Control and Prevention regarding universal screening for Group B Streptococcus (GBS) at 35-37 weeks gestational age in pregnancy is not accepted in Israel. The National Council for Obstetrics, Neonatology and Genetics recommends intrapartum prophylaxis, mainly based on risk factors, to prevent early neonatal GBS infection. This policy is based on past studies demonstrating low colonization rates of the bacteria in Israeli pregnant women and very low neonatal sepsis rates. OBJECTIVES: To determine the applicability of the high-risk group prophylaxis policy for Arab Israeli pregnant women. METHODS: Vaginorectal swabs from Arab Israeli pregnant women who attended the labor ward between October 2015 and February 2016, were obtained before any pelvic examination for GBS identification using Quidel's AmpliVue® GBS assay. Women who tested positive received intrapartum antibiotic prophylaxis to prevent neonatal infection. Obstetric data were collected from each woman from a standardized questionnaire. Data regarding the delivery and neonates were collected as well. RESULTS: The study comprised 188 Arab pregnant women who met the inclusion criteria and signed a consent form to participate in the study. Of these, 59 had positive tests, and a carriage rate of 31%. No neonatal colonization of GBS was found. CONCLUSIONS: The carrier rate in Arab pregnant women in northern Israel is higher than the national average, at least partially due to the more sensitive method of GBS detection used in the present study.


Subject(s)
Pregnancy Complications, Infectious/diagnosis , Pregnancy Complications, Infectious/epidemiology , Streptococcal Infections/diagnosis , Streptococcal Infections/epidemiology , Streptococcus agalactiae/isolation & purification , Adult , Arabs , Female , Humans , Israel/epidemiology , Pregnancy , Prospective Studies , Risk Factors
2.
ACS Nano ; 10(6): 5891-9, 2016 06 28.
Article in English | MEDLINE | ID: mdl-27166639

ABSTRACT

Highly selective detection, rapid response (<20 s), and superior sensitivity (Rair/Rgas> 50) against specific target gases, particularly at the 1 ppm level, still remain considerable challenges in gas sensor applications. We propose a rational design and facile synthesis concept for achieving exceptionally sensitive and selective detection of trace target biomarkers in exhaled human breath using a protein nanocage templating route for sensitizing electrospun nanofibers (NFs). The mesoporous WO3 NFs, functionalized with well-dispersed nanoscale Pt, Pd, and Rh catalytic nanoparticles (NPs), exhibit excellent sensing performance, even at parts per billion level concentrations of gases in a humid atmosphere. Functionalized WO3 NFs with nanoscale catalysts are demonstrated to show great promise for the reliable diagnosis of diseases.


Subject(s)
Biomarkers/analysis , Nanofibers , Tungsten , Breath Tests , Catalysis , Humans , Oxides
3.
Nanoscale ; 7(39): 16417-26, 2015 Oct 21.
Article in English | MEDLINE | ID: mdl-26395290

ABSTRACT

Bio-inspired Pt (∼2 nm) and Au (∼2.7 nm) catalysts encapsulated by a protein shell, i.e., Pt-apoferritin (Pt@AF) and Au-apoferriten (Au@AF), were synthesized via the hollow protein nanocage (apoferritin) templating route and directly functionalized on the interior and exterior walls of electrospun SnO2 nanotubes (NTs) during controlled single-nozzle electrospinning followed by high temperature calcination with heating rate control. Fast crystallization of the exterior shell and outward diffusion of the interior Sn precursors and crystallites result in the continued growth of a tubular wall, which is related to rapid heating driven Ostwald-ripening behavior. Very importantly, the Pt and Au nanoparticles (NPs) were immobilized onto thin-walled SnO2 NTs with a diameter of ∼350 nm and a shell thickness of ∼40 nm without any aggregation of catalysts due to high dispersibility, which originated from repulsive electrostatic (Coulombic) forces acting on the surface charged protein shells, leading to an enhanced catalytic effect and outstanding gas sensing properties. Pt-loaded SnO2 NTs exhibited superior acetone response (R(air)/R(gas) = 92 at 5 ppm) compared to pure SnO2 NFs (R(air)/R(gas) = 4.8 at 5 ppm) and SnO2 NTs (Rair/Rgas = 11 at 5 ppm) while Au-loaded SnO2 NTs showed a high response when exposed to hydrogen sulfide (R(air)/R(gas) = 34 at 5 ppm), offering selective gas detection with minimal cross-sensitivity against other interfering gases such as NH3, CO, NO, C6H5CH3, and C5H12. Our results provide a new insight into facile, cost-effective, and highly dispersible catalyst loading on the interior and exterior walls of hollow metal oxide NTs via simple electrospinning as a potential breath analyzer.


Subject(s)
Acetone/analysis , Apoferritins/chemistry , Gold/chemistry , Hydrogen Sulfide/analysis , Nanotubes/chemistry , Platinum/chemistry , Tin Compounds/chemistry , Catalysis , Nanotubes/ultrastructure
4.
Sci Rep ; 5: 8067, 2015 Jan 28.
Article in English | MEDLINE | ID: mdl-25626399

ABSTRACT

Tailoring of semiconducting metal oxide nanostructures, which possess controlled pore size and concentration, is of great value to accurately detect various volatile organic compounds in exhaled breath, which act as potential biomarkers for many health conditions. In this work, we have developed a very simple and robust route for controlling both the size and distribution of spherical pores in electrospun WO3 nanofibers (NFs) via a sacrificial templating route using polystyrene colloids with different diameters (200 nm and 500 nm). A tentacle-like structure with randomly distributed pores on the surface of electrospun WO3 NFs were achieved, which exhibited improved surface area as well as porosity. Porous WO3 NFs with enhanced surface area exhibited high gas response (Rair/Rgas = 43.1 at 5 ppm) towards small and light H2S molecules. In contrast, porous WO3 NFs with maximized pore diameter showed a high response (Rair/Rgas = 2.8 at 5 ppm) towards large and heavy acetone molecules. Further enhanced sensing performance (Rair/Rgas = 65.6 at 5 ppm H2S) was achieved by functionalizing porous WO3 NFs with 0.1 wt% non-oxidized graphene (NOGR) flakes by forming a Schottky barrier (ΔΦ = 0.11) at the junction between the WO3 NFs (Φ = 4.56 eV) and NOGR flakes (Φ = 4.67 eV), which showed high potential for the diagnosis of halitosis.

6.
J Thorac Oncol ; 7(10): 1528-33, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22929969

ABSTRACT

INTRODUCTION: The search for non-invasive diagnostic methods of lung cancer (LC) has led to new avenues of research, including the exploration of the exhaled breath. Previous studies have shown that LC can, in principle, be detected through exhaled-breath analysis. This study evaluated the potential of exhaled-breath analysis for the distinction of benign and malignant pulmonary nodules (PNs). METHODS: Breath samples were taken from 72 patients with PNs in a prospective trial. Profiles of volatile organic compounds were determined by (1) gas chromatography/mass spectrometry (GC-MS) combined with solid-phase microextraction and (2) a chemical nanoarray. RESULTS: Fifty-three PNs were malignant and 19 were benign with similar smoking histories and comorbidities. Nodule size (mean ± SD) was 2.7 ± 1.7 versus 1.6 ± 1.3 cm (p = 0.004), respectively. Within the malignant group, 47 were non-small-cell lung cancer and six were small-cell lung cancer. Thirty patients had early-stage disease and 23 had advanced disease. Gas chromatography/mass spectrometry analysis identified a significantly higher concentration of 1-octene in the breath of LC, and the nanoarray distinguished significantly between benign versus malignant PNs (p < 0.0001; accuracy 88 ± 3%), between adeno- and squamous-cell carcinomas [LINE SEPARATOR](p < 0.0001; 88 ± 3%) and between early stage and advanced disease (p < 0.0001; 88 ± 2%). CONCLUSIONS: In this pilot study, breath analysis discriminated benign from malignant PNs in a high-risk cohort based on LC-related volatile organic compound profiles. Furthermore, it discriminated adeno- and squamous-cell carcinoma and between early versus advanced disease. Further studies are required to validate this noninvasive approach, using a larger cohort of patients with PNs detected by computed tomography.


Subject(s)
Adenocarcinoma/diagnosis , Carcinoma, Large Cell/diagnosis , Carcinoma, Non-Small-Cell Lung/diagnosis , Carcinoma, Squamous Cell/diagnosis , Lung Neoplasms/diagnosis , Small Cell Lung Carcinoma/diagnosis , Volatile Organic Compounds/analysis , Adenocarcinoma/metabolism , Aged , Breath Tests , Carcinoma, Large Cell/metabolism , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Squamous Cell/metabolism , Female , Gas Chromatography-Mass Spectrometry , Humans , Lung Neoplasms/metabolism , Male , Middle Aged , Neoplasm Staging , Pilot Projects , Prognosis , Prospective Studies , Small Cell Lung Carcinoma/metabolism , Solid Phase Microextraction
7.
Nat Nanotechnol ; 4(10): 669-73, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19809459

ABSTRACT

Conventional diagnostic methods for lung cancer are unsuitable for widespread screening because they are expensive and occasionally miss tumours. Gas chromatography/mass spectrometry studies have shown that several volatile organic compounds, which normally appear at levels of 1-20 ppb in healthy human breath, are elevated to levels between 10 and 100 ppb in lung cancer patients. Here we show that an array of sensors based on gold nanoparticles can rapidly distinguish the breath of lung cancer patients from the breath of healthy individuals in an atmosphere of high humidity. In combination with solid-phase microextraction, gas chromatography/mass spectrometry was used to identify 42 volatile organic compounds that represent lung cancer biomarkers. Four of these were used to train and optimize the sensors, demonstrating good agreement between patient and simulated breath samples. Our results show that sensors based on gold nanoparticles could form the basis of an inexpensive and non-invasive diagnostic tool for lung cancer.


Subject(s)
Breath Tests/methods , Exhalation , Gold , Lung Neoplasms/diagnosis , Metal Nanoparticles , Adult , Computer Simulation , Gas Chromatography-Mass Spectrometry , Health , Humans , Middle Aged , Principal Component Analysis
8.
ACS Nano ; 3(5): 1258-66, 2009 May 26.
Article in English | MEDLINE | ID: mdl-19397334

ABSTRACT

In this study, we use an experimental model of bilateral nephrectomy in rats to identify an advanced, yet simple nanoscale-based approach to discriminate between exhaled breath of healthy states and of chronic renal failure (CRF) states. Gas chromatography/mass spectroscopy (GC-MS) in conjugation with solid-phase microextraction (SPME) of healthy and CRF breath, collected directly from the trachea of the rats, identified 15 common volatile organic compounds (VOCs) in all samples of healthy and CRF states and 27 VOCs that appear in CRF but not in healthy states. Online breath analysis via an array of chemiresistive random network of single-walled carbon nanotubes (SWCNTs) coated with organic materials showed excellent discrimination between the various breath states. Stepwise discriminate analysis showed that enhanced discrimination capacity could be achieved by decreasing the humidity prior to their analysis with the sensors' array. Furthermore, the analysis showed the adequacy of using representative simulated VOCs to imitate the breath of healthy and CRF states and, therefore, to train the sensors' array the pertinent breath signatures. The excellent discrimination between the various breath states obtained in this study provides expectations for future capabilities for diagnosis, detection, and screening various stages of kidney disease, especially in the early stages of the disease, where it is possible to control blood pressure and protein intake to slow the progression.


Subject(s)
Breath Tests/methods , Kidney Failure, Chronic/diagnosis , Kidney Failure, Chronic/metabolism , Kidney Function Tests/methods , Nanotubes, Carbon/chemistry , Volatile Organic Compounds/analysis , Volatile Organic Compounds/chemistry , Animals , Rats , Reproducibility of Results , Sensitivity and Specificity
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