Molecular characterization of bacteria isolated from the Kingdom of Saudi Arabia and their uses against pathogenic fungi causing dermatological diseases

Random amplified polymorphic DNA (RAPD) assay and antimicrobial activities were used for the detection of genetic variations of antimicrobial isolates from the Kingdom Saudi of Arabia. Soil samples were collected  from El-Madina El-Monawara, El–Taif, El-Jouf and El-Dammam for bacterial isolation. Bacterial isolates were  evaluated for their antimicrobial activities against pathogenic fungi which cause dermatological diseases;  Acremonium sp., Microsporium gypseum, Microsporium gallinae, Exserohilum sp., Trichphyton sp. and  Aspergillus niger. Results indicate that all the bacterial isolates showed different levels of antagonistic  activities against the pathogenic fungi. Esherichia coli M2, Bacillus megaterium M3 and Bacillus subtilis M10  showed strong effect against all the tested pathogenic fungi. B. subtilis J1 isolate showed strong effect against  the two pathogenic fungi M. gallinae and Exserohilum sp. Nine strains were tested for their antibiotic response. The results show that different antibiotic response was found. RAPD fingerprinting technique was applied to  study the genetic diversity among the tested strains. Results indicate that there was a significant genomic  diversity among the B. subtilis strains and this diversity was highly correlated with habitats and the  antagonistic effect of the studied strains.Key words: Random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR), bacterial isolates, pathogenic fungi, Kingdom of Saudi Arabia

Polymeric nanocarriers: A promising tool for early diagnosis and efficient treatment of colorectal cancer

Background: Colorectal cancer (CRC) is the third most prevalent type of cancer for incidence and second for mortality worldwide. Late diagnosis and inconvenient and expensive current diagnostic tools largely contribute to the progress of the disease. The use of chemotherapy in the management of CRC significantly reduces tumor growth, metastasis, and morbidity rates. However, poor solubility, low cellular uptake, nonspecific distribution, multiple drug resistance and unwanted adverse effects are still among the major drawbacks of chemotherapy that limit its clinical significance in the treatment of CRC. Owing to their remarkable advantages over conventional therapies, the use of nanotechnology-based delivery systems especially polymeric nanocarriers (PNCs) has revolutionized many fields including disease diagnosis and drug delivery.Aim of Review: In this review, we shed the light on the current status of using PNCs in the diagnosis and treatment of CRC with a special focus on targeting strategies, surface modifications and safety concerns for different types of PNCs in colonic cancer delivery.Key Scientific Concepts of Review: The review explores the current progress on the use of PNCs in the diagnosis and treatment of CRC with a special focus on the role of PNCs in improvement of cellular uptake, drug targeting and co-delivery of chemotherapeutic agents. Possible toxicity and biocompatibility issues related to the use of PNCs and imitations and future recommendation for the use of those smart carriers in the diagnosis and treatment of CRC are also discussed.Acknowledgement This research was supported by Univeristy of Sharjah (UOS) tar-geted research project funds, 2101110345 to MH

Parasitic Contamination of Commonly Consumed Fresh Leafy Vegetables in Benha, Egypt

This study evaluated the degree of parasitic contamination of vegetables which are commercialized and consumed fresh in Benha, Egypt. It included 530 vegetables: lettuce, watercress, parsley, green onion, and leek. Vegetables were collected randomly from markets within Benha. Samples were washed in saline, and the resulting washing solution was filtered and centrifuged to concentrate the parasitic stages. Sediments and supernatants were examined by iodine and modified Ziehl-Neelsen stained smears. Intestinal parasites were detected in 157/530 (29.6%) samples. Giardia lamblia cysts were the most prevalent parasite (8.8%) followed by Entamoeba spp. cysts (6.8%), Enterobius vermicularis eggs (4.9%), various helminth larvae (3.6%), Hymenolepis nana eggs (2.8%), Hymenolepis diminuta eggs (2.1%), and Ascaris lumbricoides eggs (0.6%). The highest contaminated vegetable was lettuce (45.5%) followed by watercress (41.3%), parsley (34.3%), green onion (16.5%), and leek (10.7%). These results indicate a significant seasonal variation ( < 0.05), with highest prevalence in summer (49%) and the lowest in winter (10.8%). These findings provide evidence for the high risk of acquiring parasitic infection from the consumption of raw vegetables in Benha, Egypt. Effective measures are necessary to reduce parasitic contamination of vegetables

Influence of reactive sputtering process parameters on the structure and properties of TiO 2 thin films

Recently, titanium dioxide (TiO2) thin films have attracted significant attention and became a major area of research since the discovery of its photocatalytic effect on water. TiO2 is characterized by high chemical stability, mechanical hardness and optical transmittance as well as by a high refractive index. Therefore it is used in a variety of applications including solar energy conversion, optical coatings and protective layers. TiO2 thin films can crystallize in two crystalline structures, anatase and rutile. Anatase is metastable at room temperature while rutile is the thermodynamically stable phase. Each phase is characterized by its specific physical properties and related applications. The rutile phase for example is known for its comparatively high mass density (4.23 g/cm3) and high refractive index of up to 2.75 at 589 nm. Hence, it is highly suitable for applications like antireflective coatings. The anatase phase in turn is characterized by a very pronounced photocatalytic activity in combination with hydrophobicity. Consequently, it is applied to fabricate self-cleaning, antifogging glass and antibacterial surfaces. It is also used for water and air purification. In this work, an atomistic understanding of the growth of TiO2 thin films under the influence of various sputtering process parameters has been developed. It has been demonstrated that tailoring the structure of the reactively sputtered TiO2 thin films is possible by controlling the sputtering process parameters. Different sputtering techniques like dcMS, IBAS and HiPIMS have been utilized to fabricate TiO2 thin films. These films exhibit two crystalline structures, namely anatase and rutile. Sample preparation has been performed at different conditions, varying e.g. energetic bombardment, oxygen partial pressure and film thickness. It has been found that the formation of each phase is governed by specific parameters. For instance, energetic bombardment promotes the growth of the rutile structure. On the other hand, the growth of the anatase phase profits from the absence or very weak ion bombardment. Additionally, the anatase phase was often found for growth at high oxygen partial pressure or for thick films, whereas a rutile structure was formed otherwise. Additional substrate heating was also found to support the formation of the anatase phase. It has been demonstrated that energetic bombardment plays a dominant role in the structure formation. It has been proven that the bombardment of the growing film with highly energetic negative oxygen ions inherent in the sputtering process promotes the growth of the rutile structure. This has been observed by an investigation of the sample profile utilizing new and aged targets, since the distribution of oxygen ion bombardment along the substrate depends on the age of the target. Further support was found from investigating films grown in a HiPIMS process, where the negative oxygen ions with high energies are the dominant species governing structure formation. Furthermore, pure rutile films have also been grown under additional ion bombardment in an ion-assisted DC sputtering process. These results also show that the ion bombardment selectively hindered the formation of the anatase phase. The investigation of the structure under the influence of O+ ion and Xe+ ion bombardment has indicated that the nature of the bombarding species does not play a role in structure formation. Reducing the intensity of the energetic oxygen ion bombardment from the sputter target has enabled the formation of pure anatase structure. It has also been shown that the ion bombardment has a strong influence on the surface topography. Two surface features can be clearly distinguished that were proposed to represent rutile and anatase grains. It has also been demonstrated that purely rutile films grown in the HiPIMS process are thermally stable. The impact of highly energetic oxygen ions to the growing film has led to the formation of compressive stress which is dependent on the various process parameters. The films show an inhomogeneous distribution of the rutile and anatase phases upon increasing the film thickness. Rocking curve scans at small incidence angle have shown that the rutile phase grows at the substrate-film interface. With increasing thickness, the anatase phase overgrows the rutile phase. First evidence for this has been found from a simulation of the rocking curve scans for different film structures. TEM measurements finally confirmed the postulated growth mode. The measurements show that the growth of the rutile phase is usually observed at the substrate interface. Few anatase grains nucleate at the interface and overgrow the rutile grains in a conical manner

Influence of reactive sputtering process parameters on the structure and properties of TiO 2 thin films

Recently, titanium dioxide (TiO2) thin films have attracted significant attention and became a major area of research since the discovery of its photocatalytic effect on water. TiO2 is characterized by high chemical stability, mechanical hardness and optical transmittance as well as by a high refractive index. Therefore it is used in a variety of applications including solar energy conversion, optical coatings and protective layers. TiO2 thin films can crystallize in two crystalline structures, anatase and rutile. Anatase is metastable at room temperature while rutile is the thermodynamically stable phase. Each phase is characterized by its specific physical properties and related applications. The rutile phase for example is known for its comparatively high mass density (4.23 g/cm3) and high refractive index of up to 2.75 at 589 nm. Hence, it is highly suitable for applications like antireflective coatings. The anatase phase in turn is characterized by a very pronounced photocatalytic activity in combination with hydrophobicity. Consequently, it is applied to fabricate self-cleaning, antifogging glass and antibacterial surfaces. It is also used for water and air purification. In this work, an atomistic understanding of the growth of TiO2 thin films under the influence of various sputtering process parameters has been developed. It has been demonstrated that tailoring the structure of the reactively sputtered TiO2 thin films is possible by controlling the sputtering process parameters. Different sputtering techniques like dcMS, IBAS and HiPIMS have been utilized to fabricate TiO2 thin films. These films exhibit two crystalline structures, namely anatase and rutile. Sample preparation has been performed at different conditions, varying e.g. energetic bombardment, oxygen partial pressure and film thickness. It has been found that the formation of each phase is governed by specific parameters. For instance, energetic bombardment promotes the growth of the rutile structure. On the other hand, the growth of the anatase phase profits from the absence or very weak ion bombardment. Additionally, the anatase phase was often found for growth at high oxygen partial pressure or for thick films, whereas a rutile structure was formed otherwise. Additional substrate heating was also found to support the formation of the anatase phase. It has been demonstrated that energetic bombardment plays a dominant role in the structure formation. It has been proven that the bombardment of the growing film with highly energetic negative oxygen ions inherent in the sputtering process promotes the growth of the rutile structure. This has been observed by an investigation of the sample profile utilizing new and aged targets, since the distribution of oxygen ion bombardment along the substrate depends on the age of the target. Further support was found from investigating films grown in a HiPIMS process, where the negative oxygen ions with high energies are the dominant species governing structure formation. Furthermore, pure rutile films have also been grown under additional ion bombardment in an ion-assisted DC sputtering process. These results also show that the ion bombardment selectively hindered the formation of the anatase phase. The investigation of the structure under the influence of O+ ion and Xe+ ion bombardment has indicated that the nature of the bombarding species does not play a role in structure formation. Reducing the intensity of the energetic oxygen ion bombardment from the sputter target has enabled the formation of pure anatase structure. It has also been shown that the ion bombardment has a strong influence on the surface topography. Two surface features can be clearly distinguished that were proposed to represent rutile and anatase grains. It has also been demonstrated that purely rutile films grown in the HiPIMS process are thermally stable. The impact of highly energetic oxygen ions to the growing film has led to the formation of compressive stress which is dependent on the various process parameters. The films show an inhomogeneous distribution of the rutile and anatase phases upon increasing the film thickness. Rocking curve scans at small incidence angle have shown that the rutile phase grows at the substrate-film interface. With increasing thickness, the anatase phase overgrows the rutile phase. First evidence for this has been found from a simulation of the rocking curve scans for different film structures. TEM measurements finally confirmed the postulated growth mode. The measurements show that the growth of the rutile phase is usually observed at the substrate interface. Few anatase grains nucleate at the interface and overgrow the rutile grains in a conical manner

Solution Blowing Spinning Technology towards Green Development of Urea Sensor Nanofibers Immobilized with Hydrazone Probe

Cellulose has been one of the most widespread materials due to its renewability, excellent mechanical properties, biodegradability, high absorption ability, biocompatibility and cheapness. Novel, simple and green colorimetric fibrous film sensor was developed by immobilization of urease enzyme (U) and tricyanofuran hydrazone (TCFH) molecular probe onto cellulose nanofibers (CNF). Cellulose acetate nanofibers (CANF) were firstly prepared from cellulose acetate using the simple, green and low cost solution blowing spinning technology. The produced CANF was exposed to deacetylation to introduce CNF, which was then treated with a mixture of TCFH and urease enzyme to introduce CNF-TCFH-U nanofibrous biosensor. CNF were reinforced with tricyanofuran hyrazone molecular probe and urease enzyme was encapsulated into calcium alginate biopolymer to establish a biocomposite film. This CNF-TCFH-U naked-eye sensor can be applied as a disposable urea detector. CNF demonstrated a large surface area and was utilized as a carrier for TCFH, which is the spectroscopic probe and urease is a catalyst. The biochromic CNF-TCFH-U nanofibrous biosensor responds to an aqueous medium of urea via a visible color signal changing from off-white to dark pink. The morphology of the generated CNF and CNF-TCFH-U nanofibrous films were characterized by different analytical tools, including energy-dispersive X-ray patterns (EDX), polarizing optical microscope (POM), Fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM). SEM images of CNF-TCFH-U nanofibers demonstrated diameters between 800 nm and 2.5 μm forming a nonwoven fabric with a homogeneous distribution of TCFH/urease-containing calcium alginate nanoparticles on the surface of CNF. The morphology of the cross-linked calcium alginate nanoparticles was also explored using transmission electron microscopy (TEM) to indicate an average diameter of 56–66 nm. The photophysical performance of the prepared CNF-TCFH-U was also studied by CIE Lab coloration parameters. The nanofibrous film biosensor displayed a relatively rapid response time (5–10 min) and a limit of detection as low as 200 ppm and as high as 1400 ppm. Tricyanofuran hydrazone is a pH-responsive disperse dye comprising a hydrazone detection group. Determination of urea occurs through a proton transfer from the hydrazone group to the generated ammonia from the reaction of urea with urease

Preparation of Multifunctional Plasma Cured Cellulose Fibers Coated with Photo-Induced Nanocomposite toward Self-Cleaning and Antibacterial Textiles

Multifunctional fibrous surfaces with ultraviolet protection, self-cleaning, or antibacterial activity have been highly attractive. Nanocomposites consisting of silver (AgNPs) and titanium dioxide (TiO2 NPs) nanoparticles (Ag/TiO2) were developed and coated onto the surface of viscose fibers employing a straightforward pad–dry–cure procedure. The morphologies and elemental compositions were evaluated by scan electron microscopy (SEM), infrared spectra (FTIR), and energy-dispersion X-ray spectra (EDS). The resultant multifunctional textile materials displayed antibacterial and photo-induced catalytic properties. The photocatalyzed self-cleaning properties were investigated employing the photochemical decay of methylthioninium chloride, whereas the antibacterial properties were studied versus E. coli. The viscose fibers coated with Ag/TiO2 nanocomposite demonstrated improved efficiency compared with viscose fibers coated with pure anatase TiO2 nano-scaled particles