Disinfection of bacteria in water systems by using electrolytically generated copper:silver and reduced levels of free chlorine

As an alternative disinfectant to chlorination, electrolytically generated copper:silver (400 and 40 micrograms/L copper and silver, respectively) with and without free chlorine (0.3 mg/L) was evaluated over a period of 4 weeks in indoor and outdoor water systems (100 L tap water with natural body flora and urine). Numbers of total coliform, pseudomonas, and staphylococci were all less than drinking water standards in systems treated with copper:silver and free chlorine and systems treated with free chlorine alone (1.0 mg/L). No significant differences (p less than or equal to 0.05) in bacterial numbers were observed between systems with copper:silver and free chlorine and those with free chlorine alone. Overall, free-chlorine treatments (0.3 or 1.0 mg/L) showed significantly lower heterotrophic plate numbers than those without free chlorine. When challenged with a natural Staphylococcus sp. isolate, water with copper:silver and free chlorine had a 2.4 log10 reduction in bacterial numbers within 2 min, while free chlorine alone or copper:silver alone showed 1.5 and 0.03 log10 reductions, respectively. Addition of copper:silver to water systems may allow the concentration of free chlorine to be reduced while still providing comparable sanitary quality of the water.     

Characterisation of H+ and Cu2+ binding to humic and fulvic acids

Abstract

The nature of H⁺ and Cu²⁺ binding by soil-derived humic (HA) and fulvic (FA) acid was characterised using potentiometric titrations. The experimental data obtained showed that the derived proton balance equation was valid and capable of describing proton consumption by both polyelectrolytes. HA was found to be more acidic and more reactive as shown by its lower equivalent weight compared to FA. Acid consumption by HA during titrations was little affected at ionic strength (μ) up to 0.1 M although it was enhanced at higher μ. Displacement of protons by Cu²⁺ resulted in a nonlinear sigmoidal pattern suggesting the formation of different Cu-HA chelates, or existence of sites that differed in their affinities for Cu on the ligand. Different concentrations of added Cu appeared to favour one or both mechanisms, although the titration method could not differentiate which of the probable mechanisms was more dominant at a specific level of Cu added. Similar values were obtained for conditional stability constants using either the equation of Scatchard or Ruzic.     

Metastatic Hurthle Cell Carcinoma of the thyroid presenting as a Breast Lump: A Case Report

Background

Hurthle cell carcinoma of the thyroid is a rare form of thyroid cancer. It may present as a low grade tumour or can present as a more aggressive metastatic carcinoma. Hurthle cell carcinoma has the highest incidence of metastasis among all differentiated thyroid cancers. Most commonly haematogenous spread to lungs, bones and brain, however spread to regional lymph nodes is not uncommon. The breast is a rare site for metastasis from extramammary sources. We present the first case of breast metastasis from Hurthle cell carcinoma of the thyroid.

Case presentation

We report a 77 year old lady who had total thyroidectomy and bilateral neck dissection followed by radiotherapy for a high grade metastatic Hurthle cell carcinoma of the thyroid. Ten months later she presented to the breast clinic with left breast lump and a lump at the left axilla. Fine needle aspiration cytology of the lumps and histology after wide local excision of the breast lump confirmed metastatic Hurthle cell carcinoma.

Conclusion

The presence of breast lumps in patients with history of extramammary cancer should raise the possibility of metastasis.

     

Coffee production in southern Saudi Arabian highlands: Current status and water conservation

Work aimed at assessing status and introducing water conservation regimes for coffee production in southern Saudi Arabian highlands. Data on farm locations, altitudes, areas, practices, irrigation, tree density, and annual coffee production were analyzed. Field experiment using chlorophyll fluorescence and different irrigation regimes was conducted to examine effects of reducing irrigation frequency on photosynthesis. Results indicated that Coffea arabica L. is commonly grown at altitudes of 1300–1400 m. Plants grown at 4–6 Trees m^?2 using 100 kg ha^?1 mineral fertilizer produce an average of 3 t ha^?1. High frequency 2-day-intervals irrigation regime practiced by farmers during the dry season presents ecological challenge to limited local artesian water resources. Changes in chlorophyll fluorescence under 14-day-intervals irrigation regime initiated water stress that markedly inhibited Photosystem II efficiency and quantum yield and increased non-photochemical energy dissipation. Applying a 7-day-intervals irrigation regime induced less inhibitory effects on Photosystem II. Results also indicated that shifting from 2-day-intervals irrigation regime to 7-day-intervals regime improves coffee agroecology and directs coffee production towards sustainability.     

Pharmacokinetic and pharmacodynamic interaction of Rosuvastatin calcium with guggulipid extract in rats

Background & objectivesRosuvastatin calcium (RC) is a potent and competitive synthetic inhibitor of HMG-CoA reductase used for the treatment of dyslipidemia. Guggulipid obtained from Commiphora mukul is used in the treatment of a wide variety of diseases such as atherosclerosis, hypercholesterolemia, rheumatism, and obesity. The present study evaluates the pharmacokinetic and pharmacodynamic interactions between RC and the standardized guggulipid extract in rats.Materials and methodsThe guggulipid extract was standardized for the presence of guggulsterones. The pharmacokinetic interaction was determined after a single dose administration of RC alone or in combination with the guggulipid extract or after multiple-dose administration of RC alone or RC along with the guggulipid extract for 14 days. To determine the pharmacodynamic interaction, RC and guggulipid extract were administered to hyperlipidemic rats for 14 days. The level of significance was determined using unpaired student’s t-test, one way ANOVA, the post-ANOVA Tukey test.ResultsStandardization of guggulipid extract showed it contains 7.5%w/w of guggulsterones. Guggulipid extract increased the bioavailability of RC in both single-dose and multiple-dose studies. Guggulipid extract reduced the rate of absorption (Ka) of RC but showed an increase in maximum serum concentration (Cmax). An in-vitro study using isolated rat intestine revealed that guggulipid extract decreased the rate of absorption of RC in the intestinal lumen. The hypolipidemic activity of RC was augmented by the guggulipid extract in hyperlipidemic rats.Interpretation & conclusionTherefore it is concluded that guggulipid extract increases the bioavailability of RC by delaying its Ka and augments its hypolipidemic action. However, it is recommended that a combination of RC with guggulipid extract should be used only after an adverse effect(s) of this combination are determined.     

Social media user’s knowledge on soil plant relationship in Saudi Arabia

The study aimed to investigate the soil-plant relationship by looking at knowledge levels of social media users. The study examined the relationship between the users’ characteristics and their knowledge on soil-plant relationship. Online survey was designed and distributed to gather the data. The number of response was received from 383 respondents where 375 participants provided completed information and the remaining eight responses were eliminated due to quality standards. The results show most of the participants (68.8%) are moderately depend on social media to acquire knowledge on soil-plant relationship and indicated “Twitter” as the highly utilized platform followed by the “Youtube”. Meanwhile, 48.8% of the participants indicated that social media have a high impact on their knowledge-based information on soil-plant relationship and agricultural contents. Inferential analysis shows there was a significant positive relationship (p < 0.01) between independent variables; Twitter, Youtube, Instagram, and Snapchat and the degree of trust on these platforms, and the level’s knowledge on soil-plant relationship (dependent variable). Only 13% of the variance accounted for the impact of social media on participants’ agricultural knowledge-base can be predicted from the combination of participants’ reliance on a set of social media platforms (Twitter, Instagram, Youtube, and Snapchat). The study revealed the trust and confidence of the users using social media on agricultural information/soil plant relationship had a medium effect in social and educational research.     

Structure and Stability Analysis of Cytotoxic Complex of Camel α-Lactalbumin and Unsaturated Fatty Acids Produced at High Temperature

Abstract

α-Lactalbumin (α-La), together with oleic acid can be converted to a complex, which kills tumor cells selectively. Cytotoxic α-La -oleic acid and a-La -linoleic acid complexes were generated by adding fatty acid to camel holo a-La at 60°C (referred to as La-OA-60 and La-LA-60 state, respectively). Structural properties of these complexes were studied and compared to the camel α-La. The experimental results show that linoleic acid induces a-La partial unfolding but oleic acid does not change the protein structure significantly. Also the stability of La-OA-60 and La- LA-60 toward thermal denaturation was measured. The order of temperature at the transition midpoint is as follows: La-LA-60 < La-0A-60 < α-La. La-0A-60 complex inhibited tubulin polymerization in vitro. Although the structures of La-0A-60 and La-LA-60 were different, these two complexes had similar cytotoxic effect to DU145 human prostate cancer cells. Samples of La-0A-60 that have been renatured after denaturation lost the specific biological activity toward tumor cells.     

Modeling,simulations, and optimization of smooth muscle cell tissue engineering for the production of vascular grafts

The paper presents a transient, continuum, two-phase model of the tissue engineering in fibrous scaffolds, including transport equations for the flowing culture medium, nutrient and cell concentration with transverse and in-plane diffusion and cell migration, a novel feature of local in-plane transport across a phenomenological pore and innovative layer-by-layer cell filling approach. The model is successfully validated for the smooth muscle cell tissue engineering of a vascular graft using crosslinked, electrospun gelatin fiber scaffolds for both static and dynamic cell culture, the latter in a dynamic bioreactor with a rotating shaft on which the tubular scaffold is attached. Parametric studies evaluate the impact of the scaffold microstructure, cell dynamics, oxygen transport, and static or dynamic conditions on the rate and extent of cell proliferation and depth of oxygen accessibility. An optimized scaffold of 75% dry porosity is proposed that can be tissue engineered into a viable and still fully oxygenated graft of the tunica media of the coronary artery within 2 days in the dynamic bioreactor. Such scaffold also matches the mechanical properties of the tunica media of the human coronary artery and the suture retention strength of a saphenous vein, often used as a coronary artery graft.