Shifts in the Distribution Range and Niche Dynamics of the Globally Threatened Western Tragopan (Tragopan melanocephalus) Due to Climate Change and Human Population Pressure.

The impact of a changing climate, particularly global warming, often harms the distribution of pheasants, particularly those with limited endemic ranges. To effectively create plans of action aimed at conserving species facing threats such as the Western Tragopan, (Tragopan melanocephalus; Gray, 1829; Galliformes, found in the western Himalayas), it is crucial to understand how future distributions may be affected by anticipated climate change. This study utilized MaxEnt modeling to assess how suitable the habitat of the targeted species is likely to be under different climate scenarios. While similar studies have been conducted regionally, there has been no research on this particular endemic animal species found in the western Himalayas throughout the entire distribution range. The study utilized a total of 200 occurrence points; 19 bioclimatic, four anthropogenic, three topographic, and a vegetation variable were also used. To determine the most fitting model, species distribution modeling (SDM) was employed, and the MaxEnt calibration and optimization techniques were utilized. Data for projected climate scenarios of the 2050s and 2070s were obtained from SSPs 245 and SSPs 585. Among all the variables analyzed; aspect, precipitation of coldest quarter, mean diurnal range, enhanced vegetation index, precipitation of driest month, temperature seasonality, annual precipitation, human footprint, precipitation of driest quarter, and temperature annual range were recognized as the most influential drivers, in that order. The predicted scenarios had high accuracy values (AUC-ROC > 0.9). Based on the feedback provided by the inhabitants, it was observed that the livability of the selected species could potentially rise (between 3.7 to 13%) in all projected scenarios of climate change, because this species is relocating towards the northern regions of the elevation gradient, which is farther from the residential areas, and their habitats are shrinking. The suitable habitats of the Tragopan melanocephalus in the Himalayan region will move significantly by 725 m upwards, because of predicted climate change. However, the fact that the species is considered extinct in most areas and only found in small patches suggests that further research is required to avert a further population decline and delineate the reasons leading to the regional extinction of the species. The results of this study can serve as a foundation for devising conservation strategies for Tragopan melanocephalus under the changing climate and provide a framework for subsequent surveillance efforts aimed at protecting the species.

Hybrid nanoparticulate system of Fluvastatin loaded phospholipid, alpha lipoic acid and melittin for the management of colon cancer.

As a hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, Fluvastatin (FLV) is used for reducing low-density lipoprotein (LDL) cholesterol as well as to prevent cardiovascular problems. FLV showed cell line cytotoxicity and antitumor effect. Melittin (MEL) exhibits antineoplastic activity and is known to be promising as a therapeutic option for cancer patients. The aim of this work was to investigate the combination of FLV with MEL loaded hybrid formula of phospholipid (PL) with alpha lipoic acid (ALA) nanoparticles to maximize anticancer tendencies. This study examines the optimization of the prepared formulation in order to minimize nanoparticles size and maximize zeta potential to potentiate cytotoxic potentialities in colon cancer cells (Caco2), cell viability, cell cycle analysis and annexin V were tested. In addition to biological markers as P53, Bax, bcl2 and Caspase 3 evaluation The combination involving FLV PL ALA MEL showed enhanced cytotoxic potentiality (IC50 = 9.242 ± 0.35 µg/mL), about twofold lower, compared to the raw FLV (IC50 = 21.74 ± 0.82 µg/mL). According to studies analyzing cell cycle, optimized FLV PL ALA MEL was found to inhibit Caco2 colon cancer cells more significantly than other therapeutic treatments, wherein a higher number of cells were found to accumulate over G2/M and pre-G1 phases, whereas G0/G1/S phases witnessed the accumulation of a lower number of cells. The optimized formulation may pave the way for a novel and more efficacious treatment for colon cancer.

Climate change and hydrological regime in arid lands: Impacts of dams on the plant diversity, vegetation structure and soil in Saudi Arabia.

As the direct effects of climate change on the hydrological regime, Saudi Arabia has constructed more than 522 dams of various capacities as part of economic and environmental development. The study aims to assess the impact of dams on plant diversity, vegetation structure and soil in Saudi Arabia. Thirty-five stands were selected from the dams of different sizes of Saudi Arabia. Vegetation samples were established before (upstream) and after (downstream) the dam, and at the undammed (unaffected by the dam) to compare species diversity in the dam sites and undammed sites and to document the potential effects of dams on vegetation structure. A total of 151 plant species belonging to 36 families have been recorded. The vegetation associations are essentially shrubby with widespread annuals. Six novel associations were identified with the application of TWINSPAN, DCA, and CCA programs. They were named after the characteristic species as follows: VG I: Acacia gerrardii-Caralluma retrospiciens; VGII: Acacia tortilis-Maerua oblongifolia; VGIII: Lycium shawii-Farsetia aegyptiaca; VG IV: Farsetia stylosa-Cornulaca monocantha; VG V: Suaeda aegyptiaca-Salsola imbricata-Prosopis farcta and VGVI: Xanthium strumarium-Ochradenus baccatus. These plant communities are evaluated and discussed according to their floristic structure, vegetation diversity and edaphic variables. The riparian or streamside zones upstream and downstream that are periodically flooded contain highly diverse plant communities that are structured by flooding, which creates disturbance and acts as a dispersal mechanism for plants than undammed sites.

Genetic variability of the helix 54 of the 23S rDNA and its use as a molecular target for identification of species within the viridans group streptococci (VGS).

The aim of the present study is to establish a method, based on sequence analysis of the helix 54 of 23S rRNA gene, to identify clinical relevant strains belonging to viridans group streptococci (VGS). A set of 25 randomly selected clinical isolates of alpha-hemolytic streptococci from upper respiratory tract were characterized by the routine phenotypic methods (API 20 Strep test). Molecular characterization was assessed by genotypic analysis of the nucleotide sequence of the helix 54 of 23S rRNA and Intergenic spacer region 16S23S. Partial sequencing of the gdh gene was used on 10 strains of mitis group. Sequence variations of the helix 54 allowed the identification of strains to group level and even to species level for certain strains within sanguinis and anginosus groups. Infact, species identification was ambiguous for some strains belonged to the salivarius group (of VGS16 to VGS20) and the mitis group (of VGS1 to VGS14). These results are almost similar to those obtained by sequencing the 16S23S intergenic region. Thus, we use the gdh gene sequencing for the identification of strains, not recognized, within the mitis group. The results generated herein indicate that no single methodology can be used to provide an accurate identification to the species level of all VGS, although nucleotide sequence analysis of the helix 54 of 23S rRNA gene proved to be a reliable method for the identification of VGS to the group level and even to the species level within sanguinis and anginosus groups.

Metal nanoparticles assisted revival of Streptomycin against MDRS Staphylococcus aureus.

The ability of microorganisms to generate resistance outcompetes with the generation of new and efficient antibiotics. Therefore, it is critically required to develop novel antibiotic agents and treatments to control bacterial infections. Green synthesized metallic and metal oxide nanoparticles are considered as the potential means to target bacteria as an alternative to antibiotics. Nanoconjugates have also attracted attention because of their increased biological activity as compared to free antibiotics. In the present investigation, silver nanoparticles (AgNPs), zinc oxide nanoparticles (ZnO NPs), copper oxide nanoparticles (CuO NPs), and iron oxide nanoparticles (FeO NPs) have been synthesized by using leaf extract of Ricinus communis. Characterization of nanoparticles was done by using UV-Vis Spectroscopy, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, Energy Dispersive X-Ray Analyzer, X-ray Diffraction Analysis, and Dynamic Light Scattering Particle Size Analyzer. Interestingly, Streptomycin when combined with AgNPs, ZnO NPs, CuO NPs, and FeO NPs showed enhanced antibacterial activity against clinical isolates of S. aureus which suggested synergism between the nanoparticles and antibiotics. The highest enhanced antibacterial potential of Streptomycin was observed in conjugation with ZnO NPs (11 ± 0.5 mm) against S. aureus. Minimum inhibitory concentration of conjugates of AgNPs, ZnO NPs, CuO NPs, and FeO NPs with streptomycin against S. aureus was found to be 3.12, 2.5,10, and 12.5 µg/mL respectively. The considerable point of the present investigation is that S. aureus, which was resistant to streptomycin becomes highly susceptible to the same antibiotic when combined with nanoparticles. This particular observation opens up windows to mitigate the current crisis due to antibiotic resistance to combat antimicrobial infections efficiently.

Wasp venom peptide improves the proapoptotic activity of alendronate sodium in A549 lung cancer cells.

BACKGROUND: Lung cancer in men and women is considered the leading cause for cancer-related mortality worldwide. Anti-cancer peptides represent a potential untapped reservoir of effective cancer therapy. METHODOLOGY: Box-Behnken response surface design was applied for formulating Alendronate sodium (ALS)-mastoparan peptide (MP) nanoconjugates using Design-Expert software. The optimization process aimed at minimizing the size of the prepared ALS-MP nanoconjugates. ALS-MP nanoconjugates' particle size, encapsulation efficiency and the release profile were determined. Cytotoxicity, cell cycle, annexin V staining and caspase 3 analyses on A549 cells were carried out for the optimized formula. RESULTS: The results revealed that the optimized formula was of 134.91±5.1 nm particle size. The novel ALS-MP demonstrated the lowest IC50 (1.3 ± 0.34 µM) in comparison to ALS-Raw (37.6 ± 1.79 µM). Thus, the results indicated that when optimized ALS-MP nanoconjugate was used, the IC50 of ALS was also reduced by half. Cell cycle analysis demonstrated a significantly higher percentage of cells in the G2-M phase following the treatment with optimized ALS-MP nanoconjugates. CONCLUSION: The optimized ALS-MP formula had significantly improved the parameters related to the cytotoxic activity towards A549 cells, compared to control, MP and ALS-Raw.

Comprehensive Review of the Properties and Modifications of Carbon Fiber-Reinforced Thermoplastic Composites.

Carbon fiber-reinforced polymers are considered a promising composite for many industrial applications including in the automation, renewable energy, and aerospace industries. They exhibit exceptional properties such as a high strength-to-weight ratio and high wear resistance and stiffness, which give them an advantage over other conventional materials such as metals. Various polymers can be used as matrices such as thermosetting, thermoplastic, and elastomers polymers. This comprehensive review focuses on carbon fiber-reinforced thermoplastic polymers due to the advantages of thermoplastic compared to thermosetting and elastomer polymers. These advantages include recyclability, ease of processability, flexibility, and shorter production time. The related properties such as strength, modulus, thermal conductivity, and stability, as well as electrical conductivity, are discussed in depth. Additionally, the modification techniques of the surface of carbon fiber, including the chemical and physical methods, are thoroughly explored. Overall, this review represents and summarizes the future prospective and research developments carried out on carbon fiber-reinforced thermoplastic polymers.

Molybdenum and hydrogen sulfide synergistically mitigate arsenic toxicity by modulating defense system, nitrogen and cysteine assimilation in faba bean (Vicia faba L.) seedlings.

Hydrogen sulfide (H2S) has emerged as a potential gasotransmitter in plants with a beneficial role in stress amelioration. Despite the various known functions of H2S in plants, not much information is available to explain the associative role of molybdenum (Mo) and hydrogen sulfide (H2S) signaling in plants under arsenic toxicity. In view to address such lacunae in our understanding of the integrative roles of these biomolecules, the present work attempts to decipher the roles of Mo and H2S in mitigation of arsenate (AsV) toxicity in faba bean (Vicia faba L.) seedlings. AsV-stressed seedlings supplemented with exogenous Mo and/or NaHS treatments (H2S donor) showed resilience to AsV toxicity manifested by reduction of apoptosis, reactive oxygen species (ROS) content, down-regulation of NADPH oxidase and GOase activity followed by upregulation of antioxidative enzymes in leaves. Fluorescent localization of ROS in roots reveals changes in its intensity and spatial distribution in response to MO and NaHS supplementation during AsV stress. Under AsV toxicity conditions, seedlings subjected to Mo + NaHS showed an increased rate of nitrogen metabolism evident by elevation in nitrate reductase, nitrite reductase and glutamine synthetase activity. Furthermore, the application of Mo and NaHS in combination positively upregulates cysteine and hydrogen sulfide biosynthesis in the absence and presence of AsV stress. Mo plus NaHS-supplemented seedlings exposed to AsV toxicity showed a substantial reduction in oxidative stress manifested by reduced ELKG, lowered MDA content and higher accumulation of proline in leaves. Taken together, the present findings provide substantial evidence on the synergetic role of Mo and H2S in mitigating AsV stress in faba bean seedlings. Thus, the application of Mo and NaHS reveals their agronomic importance to encounter heavy metal stress for management of various food crops.

Exogenous Potassium (K+) Positively Regulates Na+/H+ Antiport System, Carbohydrate Metabolism, and Ascorbate-Glutathione Cycle in H2S-Dependent Manner in NaCl-Stressed Tomato Seedling Roots.

Potassium (K+) is one of the vital macronutrients required by plants for proper growth and blossoming harvest. In addition, K+ also plays a decisive role in promoting tolerance to various stresses. Under stressful conditions, plants deploy their defense system through various signaling molecules, including hydrogen sulfide (H2S). The present investigation was carried out to unravel the role of K+ and H2S in plants under NaCl stress. The results of the study show that NaCl stress caused a reduction in K+ and an increase in Na+ content in the tomato seedling roots which coincided with a lower H+-ATPase activity and K+/Na+ ratio. However, application of 5 mM K+, in association with endogenous H2S, positively regulated the Na+/H+ antiport system that accelerated K+ influx and Na+ efflux, resulting in the maintenance of a higher K+/Na+ ratio. The role of K+ and H2S in the regulation of the Na+/H+ antiport system was validated by applying sodium orthovanadate (plasma membrane H+-ATPase inhibitor), tetraethylammonium chloride (K+ channel blocker), amiloride (Na+/H+ antiporter inhibitor), and hypotaurine (HT, H2S scavenger). Application of 5 mM K+ positively regulated the ascorbate-glutathione cycle and activity of antioxidant enzymes that resulted in a reduction in reactive oxygen species generation and associated damage. Under NaCl stress, K+ also activated carbohydrate metabolism and proline accumulation that caused improvement in osmotic tolerance and enhanced the hydration level of the stressed seedlings. However, inclusion of the H2S scavenger HT reversed the effect of K+, suggesting H2S-dependent functioning of K+ under NaCl stress. Therefore, the present findings report that K+, in association with H2S, alleviates NaCl-induced impairments by regulating the Na+/H+ antiport system, carbohydrate metabolism, and antioxidative defense system.

Hydrogen sulfide (H2S) and potassium (K+) synergistically induce drought stress tolerance through regulation of H+-ATPase activity, sugar metabolism, and antioxidative defense in tomato seedlings.

KEY MESSAGE: Exogenous potassium (K+) and endogenous hydrogen sulfide (H2S) synergistically alleviate drought stress through regulating H+-ATPase activity, sugar metabolism and redox homoeostasis in tomato seedlings. Present work evaluates the role of K+ in the regulation of endogenous H2S signaling in modulating the tolerance of tomato (Solanum lycopersicum L. Mill.) seedlings to drought stress. The findings reveal that exposure of seedlings to 15% (w/v) polyethylene glycol 8000 (PEG) led to a substantial decrease in leaf K+ content which was associated with reduced H+-ATPase activity. Treatment with sodium orthovanadate (SOV, PM H+-ATPase inhibitor) and tetraethylammonium chloride (TEA, K+ channel blocker) suggests that exogenous K+ stimulated H+-ATPase activity that further regulated endogenous K+ content in tomato seedlings subjected to drought stress. Moreover, reduction in H+-ATPase activity by hypotaurine (HT; H2S scavenger) substantiates the role of endogenous H2S in the regulation of H+-ATPase activity. Elevation in endogenous K+ content enhanced the biosynthesis of H2S through enhancing the synthesis of cysteine, the H2S precursor. Synergistic action of H2S and K+ effectively neutralized drought stress by regulating sugar metabolism and redox homoeostasis that resulted in osmotic adjustment, as witnessed by reduced water loss, and improved hydration level of the stressed seedlings. The integrative role of endogenous H2S in K+ homeostasis was validated using HT and TEA which weakened the protection against drought stress induced impairments. In conclusion, exogenous K+ and endogenous H2S regulate H+-ATPase activity which plays a decisive role in the maintenance of endogenous K+ homeostasis. Thus, present work reveals that K+ and H2S crosstalk is essential for modulation of drought stress tolerance in tomato seedlings.

Calcium-hydrogen sulfide crosstalk during K+-deficient NaCl stress operates through regulation of Na+/H+ antiport and antioxidative defense system in mung bean roots.

Present investigation reports the role of calcium (Ca2+) and hydrogen sulfide (H2S) crosstalk associated with Vigna radiata seedlings subjected to K+ deficient conditions under short-term (24 h) and long-term (72 h) NaCl stress. Perusal of the data reveals that under short-term NaCl stress an initial decline in K+ level led to the elevation in Ca2+ and H2S levels along with improvement in antioxidant system and reduction in reactive oxygen species (ROS) production. Under long-term NaCl stress a further decline in K+ content was deleterious that led to a lower K+/Na+ ratio. This was followed by reduction in antioxidant system along with excessive accumulation of ROS and methylglyoxal content, and increased membrane damage. However, supplementation of the seedling roots with Ca2+ enhanced biosynthesis of H2S through enhancing cysteine pool. The present findings suggest that synergistic action of Ca2+ and H2S induced the activity of H+-ATPase that created H+ gradient which in turn induced Na+/H+ antiport system that accelerated K+ influx and Na+ efflux. All of these together contributed to a higher K+/Na+ ratio, activation of antioxidative defense system, and maintenance of redox homeostasis and membrane integrity in Ca2+-supplemented stressed seedlings. Role of Ca2+ and H2S in the regulation of Na+/H+ antiport system was validated by the use of sodium orthovanadate (plasma membrane H+-ATPase inhibitor), tetraethylammonium chloride (K+ channel blocker), and amiloride (Na+/H+ antiporter inhibitor). Application of Ca2+-chelator EGTA (ethylene glycol-bis(b-aminoethylether)-N,N,N',N'-tetraacetic acid) and H2S scavenger hypotaurine abolished the effect of Ca2+, suggesting the involvement of Ca2+ and H2S in the alleviation of NaCl stress. Moreover, use of EGTA and HT also substantiates the downstream functioning of H2S during Ca2+-mediated regulation of plant adaptive responses to NaCl stress. To sum up, present findings reveal the association of Ca2+ and H2S signaling in the regulation of ion homeostasis and antioxidant defense during K+-deficient NaCl stress.

Crosstalk of hydrogen sulfide and nitric oxide requires calcium to mitigate impaired photosynthesis under cadmium stress by activating defense mechanisms in Vigna radiata.

Hydrogen sulfide (H2S) and nitric oxide (NO) have been known to affect vast number of processes in plants under abiotic stresses. Also, calcium (Ca) works as a second messenger in plants, which underpins the abiotic stress-induced damage. However, the sequence of action of these signaling molecules against cadmium (Cd)-induced cellular oxidative damage remains unidentified. Therefore, we studied the synergistic actions and/or relationship of signaling molecules and Ca-dependent activation of tolerance mechanisms in Vigna radiata seedlings under Cd stress. The present study shows that exogenous Ca supplemented to Cd-stressed V. radiata seedlings reduced Cd accumulation and improved the activity of nitrate reductase, and L/D-cysteine desulfhydrase (LCD/DCD) that resulted in improved synthesis of NO and H2S content. Application of Ca also elevated the level of cysteine (Cys) by upregulating the activity of Cys-synthesizing enzymes serine acetyltransferase and O-acetylserine(thiol)lyase in Cd-stressed seedlings. Maintenance of Cys pool under Cd stress contributed to improved H2S content which together with Ca and NO improved antioxidant enzymes and components of ascorbate-glutathione (AsA-GSH) cycle. All these collectively regulated the activity of NADPH oxidase and glycolate oxidase, resulting in the inhibition of Cd-induced generation of reactive oxygen species. The elevated level of Cys also assisted the Cd-stressed seedlings in maintaining GSH pool which retained normal functioning of AsA-GSH cycle and led to enhanced content of phytochelatins coupled with reduced Cd content. The positive effect of these events manifested in an enhanced rate of photosynthesis, carbohydrate accumulation, and growth attributes of the plants. On the contrary, addition of NO scavenger cPTIO [2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide], H2S scavenger HT (Hypotaurine) and Ca-chelator EGTA (Ethylene glycol-bis(b-aminoethylether)-N,N,N',N'-tetraacetic acid) again developed a condition similar to stress and positive effect of the signaling molecules was abolished. The findings of the study postulate that Ca in association with NO and H2S mitigates Cd-induced impairment and enhances the tolerance of the V. radiata plants against Cd stress. The results of the study also substantiate that Ca acts both upstream as well as downstream of NO signals whereas, H2S acts downstream of Ca and NO during Cd-stress responses of the plants.

The Impact of using the term "Diabetic Ear" for the patients with Skull Base Osteomyelitis.

BACKGROUND: Diabetes and ear disease are some of the most widespread health concerns. The focus here is on the impact of using the term "Diabetic Ear" for patients with skull base osteomyelitis (SBM) in the context of malignant otitis externa (MOE). The aim of this study was to discover the awareness of general practitioners (GPs), residents, specialists, and consultants at Primary Health Care Centers about necrotizing otitis externa (NOE), also known previously as malignant external otitis (MOE), assess their deficiencies and provide solutions; also assist them for the early detection and possible prevention of diabetes- related ear diseases and their complications. MATERIALS AND METHODS: A cross-sectional study was conducted among a random sample of physicians (residents, specialists, and consultants) working at the Primary Health Care Centers in Al-Khobar and Dammam cities of the Eastern Province, Saudi Arabia. Data was collected using a standardized questionnaire. SPSS was used for data entry and analysis. RESULTS: The total number of medical practitioners was 84. Their mean age was 33.97 (±9.55). The proportion of females was higher than males, only 28.3% of the participants responded correctly when asked about MOE. Similarly, very few were aware of the risks of MOE (2.5%), complications associated with it (17.3%) and the necessary procedures for managing patients (24.2%). The awareness of doctors in the primary health clinics about MOE was significantly better than those in hospitals (P = 0.002). CONCLUSION: There was a significant deficiency in the knowledge of GPs on MOE. Therefore, health education and awareness programs on MOE are recommended. Furthermore, we recommend that it is necessary to encourage the use of the term "Diabetic EAR "to increase the level of awareness of physicians about MOE.

Synthesis, antimicrobial activity, pharmacophore modeling and molecular docking studies of new pyrazole-dimedone hybrid architectures.

BACKGROUND: Design and synthesis of pyrazole-dimedone derivatives were described by one-pot multicomponent reaction as new antimicrobial agents. These new molecular framework were synthesized in high yields with a broad substrate scope under benign conditions mediated by diethylamine (NHEt2). The molecular structures of the synthesized compounds were assigned based on different spectroscopic techniques (1H-NMR, 13C-NMR, IR, MS, and CHN). RESULTS: The synthesized compounds were evaluated for their antibacterial and antifungal activities against S. aureus ATCC 29213, E. faecalis ATCC29212, B. subtilis ATCC 10400, and C. albicans ATCC 2091 using agar Cup plate method. Compound 4b exhibited the best activity against B. subtilis and E. faecalis with MIC = 16 µg/L. Compounds 4e and 4l exhibited the best activity against S. aureus with MIC = 16 µg/L. Compound 4k exhibited the best activity against B. subtilis with MIC = 8 µg/L. Compounds 4o was the most active compounds against C. albicans with MIC = 4 µg/L. CONCLUSION: In-silico predictions were utilized to investigate the structure activity relationship of all the newly synthesized antimicrobial compounds. In this regard, a ligand-based pharmacophore model was developed highlighting the key features required for general antimicrobial activity. While the molecular docking was carried out to predict the most probable inhibition and binding mechanisms of these antibacterial and antifungal agents using the MOE docking suite against few reported target proteins.

Synthesis of Pyrazole-Thiobarbituric Acid Derivatives: Antimicrobial Activity and Docking Studies.

A one-pot reaction was described that results in various pyrazole-thiobarbituric acid derivatives as new pharmacophore agents. These new heterocycles were synthesized in high yields with a broad substrate scope under mild reaction conditions in water mediated by NHEt2. The molecular structures of the synthesized compounds were assigned based on different spectroscopic techniques. The new compounds were evaluated for their antibacterial and antifungal activity. Compounds 4h and 4l were the most active compounds against C. albicans with MIC = 4 µg/L. Compound 4c exhibited the best activity against S. aureus and E. faecalis with MIC = 16 µg/L. However, compounds 4l and 4o were the most active against B. subtilis with MIC = 16 µg/L. Molecular docking studies for the final compounds and standard drugs were performed using the OpenEye program.

Hearing loss and its association with occupational noise exposure among Saudi dentists: a cross-sectional study.

OBJECTIVES/AIMS: Dental practitioners are prone to hearing loss due to noise exposure encountered in dental clinics. The aim of this study was to determine whether the persistent high-frequency sounds produced by the dental equipment could cause hearing decrement among the Saudi dental practitioners. MATERIALS AND METHODS: This cross-sectional study included 38 randomly selected Saudi dentists from different specialties who were exposed to noise during working hours and 38 individuals as a control group. The participants underwent four audiometric tests that included an otoscopic examination, tympanometry, pure tone audiometry and the distortion product otoacoustic emissions (DPOAE) test. RESULTS: The data revealed that ~15.8% of the dentists and 2.6% of the control group had some hearing loss. No significant difference was found between the two groups in the pure tone audiometry test; however, qualitative analysis revealed a higher percentage of hearing loss among the dentists' group as compared with their control counterparts. A statistically significant difference was found in DPOAEs between the two groups in the left ear (P=0.002), and between the right and left ears (P=0.005). DISCUSSION: In the present cross-sectional study, the prevalence of hearing loss among dentists as assessed with the pure tone audiometry test was 15.8%. Which was in accordance with a previous study performed by Khaimook et al., which revealed the prevalence of hearing loss in dental personnel to be 17.7%; however, no significant differences were observed compared to the control group in both studies. The otoacoustic emission test in the left ear exhibited significant changes. These changes could have been due to the presence and continuity of the sounds produced by high- and low-velocity suction devices on the left side of the dental unit knowing that 97% of the dentists are right handed. CONCLUSION: Evidence suggests that noise from dental clinics can cause hearing problems, which had a greater effect on the left ear than the right; however, these problems are not severe in nature. Noise-induced hearing loss was more prevalent among the dentists than the control group.

The Effect of Dental Adhesive on Final Color Match of Direct Laminate Veneer (DLV): In Vitro Study.

AIM: To evaluate the influence of dental adhesive on the color match of direct laminate veneer. MATERIALS AND METHOD: Specimens were prepared in the form of discs. B1 nano-filled composite Filtek Z-350 XT (3M-ESPE) and single-bond universal adhesive were used. Twenty discs of each test group with a diameter of 10 ± 0.1 mm and thickness of 0.7 ± 0.1 mm were prepared. The specimens were divided into three groups: control group that has composite material only (C), a group that has adhesive with composite material (AC), and a group that has adhesive with composite and re-bonding technique (ACR). The samples were placed in viewing port for color measurement. Spectrophotometer was used in this study. Descriptive statistical analysis was performed for the CIE L*, a*, and b* values. Statistical software IBM SPSS 16.0 was used for analyzing the data, with a significance level of 0.05 (p < 0.05). RESULTS: In this study, both groups where bonding agent was applied had significant change in color of the samples (p < 0.05). AC and ACR showed a change along the "a" coordinate and the "b" coordinate with using adhesive and re-bonding technique. There were significant differences when comparing the values of a* and b* of the control group C with AC group and ACR on using adhesive and re-bonding technique. ACR specimens presented the lowest "L" value. CONCLUSION: Within the limitations of this study, despite the fact that the change of color is not extensive, the dental adhesive changes the color of direct composite restoration in a way that may warrant caution. Additional studies are essential to substantiate the findings of this study. CLINICAL SIGNIFICANCE: Dental adhesive play an important role in changing the color of direct composite restoration.

Primary health care physicians' knowledge, use, and attitude towards online continuous medical education in Saudi Arabia.

OBJECTIVE: To determine the knowledge, attitude, and use of primary health care (PHC) physicians of online continuous medical education (OCME) in the regions of Riyadh, Kingdom of Saudi Arabia. METHODS: This is a cross-sectional analysis using a self administered questionnaire. The physician sample was selected to cover all Riyadh regions (city of Riyadh, and all accessible clinics in the villages, and cities outside of Riyadh). The study was conducted from April until May 2007. The data were analyzed using the Statistical Package for Social Sciences software version 12. RESULTS: Out of the 613 questionnaires distributed, 483 was completed and returned. Approximately two-thirds of the participants are aware of OCME. Almost all were interested to learn more regarding OCME. Although 80% of the participants are currently using the internet to obtain medical knowledge, only one-third are using OCME. Ninety percent of those who are using OCME think that it will improve their patient's care. The use of OCME is significantly related to the level of computer skills the physicians have. There was no statistical significant difference on the use of OCME on one hand, and age, gender, level of education, years of experience, and location on the other hand. CONCLUSION: The PHC physicians have favorable attitude towards OCME, however, their use is quite minimal. More effort is needed to encourage our physicians to utilize this promising method of continuous education, and to understand the challenges and obstacles against using it.

Análisis de la interfase diente restauración en obturaciones con Ariston pHc / Analysis of the dentin restoration interphase in obturation with Ariston pHc

En el presente trabajo se analizó la interfase dentina-restauración en restauraciones con ariston PHC, un nuevo sistema de resina compuesta que se usa sin grabado ácido previo y que está indicado para dientes posteriores. En molares recientemente extraídos se confeccionaron 3 restauraciones, una siguiendo las instrucciones de uso del fabricante, otra agregando a esta técnica el uso de grabado ácido previo, y la tercera con grabado ácido y un adhesivo dentinario. Las restauraciones realizadas según esta técnica indicada por el fabricante presentaron brechas en las paredes pulpares y laterales de las cavidades, con su superficie interna rugosa e irregular, lo que sugiere la permanencia del barrio dentario después de la aplicación del liner. con el uso del grabado ácido total de la preparación cavitaria, las brechas laterales disminuyen de amplitud y en la pared pulpar no se desarrollan. En la superficie pulpar de las restauraciones aparecen estructuras de microrretención en forma de tags dentinarios y regiones de infiltración de resina en la dentina correspondiente a la zona híbrida. Los resultados sugieren que el grabado ácido total podría aumentar la retención de las restauraciones con ariston PHC mediante el desarrollo de estructuras de microrretención, aunque el posible uso clínico de tal procedimiento requiere descartar los posibles efectos tóxicos del liner ariston sobre la pulpa dentaria