Enhancement of Streptomyces thinghirensis WAE1 for production of bioactive metabolites under different optimization strategies

Isolation of novel bioactive metabolites from Streptomyces strains is a promising source for drug discovery. However, conventional screening approaches have limitations in identifying new leads due to redundant discoveries. Optimization of culture conditions is important but traditionally optimized one factor at a time, failing to consider interactions. This study addressed these gaps by enhancing metabolite production from Streptomyces thinghirensis WAE1 through statistical optimization. Various chemical and physical factors impacting metabolite production were identified. Response surface methodology with a central composite design was applied to optimize significant factors like carbon source, nitrogen source, inoculum size, pH, temperature and incubation period. This optimized production against Streptococcus pneumoniae, increasing antibacterial activity by 74.92%. Gas chromatography-mass spectrometry revealed 19 bioactive compounds, including 1,25-dihydroxyvitamin D3 inhibiting cell wall development. This highlights S. thinghirensis WAE1's potential as a bioresource and emphasizes studying metabolite production from novel Streptomyces strains to discover new antibacterial drugs.

Study on development and tissue permeation of different formulations of Fasudil

OBJECTIVE

The study is intended to formulate Fasudil loaded vesicular system for application in the management of angina.

MATERIALS AND METHODS

Fasudil was made into a complex with phospholipid, and other different formulations were made, including Fasudil solution, liposomal form, and Fasudil loaded into the gel. A drug characterization study was conducted and noted. Drug release was quantified and analyzed and, finally, inoculated in Sprague-Dawley rats. These rats underwent anginal induction, and each formulation's effect on angina was evaluated.

RESULTS

Drug solution (F-Phos) and F-Phos-Lipo (liposomal dispersion form of the drug) have shown that more than half percent of them have been released within 1.5 hours, and the rapid release occurred from liposomal dispersion in the first hour. The study determined the viscosity of the different formulations, which was significantly (p<0.05) higher than the theoretical sum of the viscosity of each formulation. The study found that the F-Phos-Lipo+P-407HMS formulation is the most effective as its application has the minimum infarct area percentage compared to the other formulations and can also reduce creatine kinase levels significantly as compared to the different formulations (p<0.05).

CONCLUSIONS

The study concluded that the typical gel formulation (liposomal Fasudil dispersed in hydroxypropyl methylcellulose solution, which is added to blank poloxamer 407) had been shown to have significantly anti-anginal properties, including easy administration, its application on the infarct area percentage and subsequently its pharmacological effect on the cardiac tissue.

Synthesis of Higher Alcohols from Syngas over a K-Modified CoMoS Catalyst Supported on Novel Powder and Fiber Commercial Activated Carbons

In the present study, a series of K-modified CoMoS catalysts with compositions of 10% K, 3.6% Co, and 12 wt % Mo supported over novel commercial activated carbons such as powder materials (DAC and OBC-1) and fiber materials (fabric active sorption (TCA) and nonwoven activated material (AHM)) were prepared and characterized by Brunauer-Emmett-Teller (BET), X-ray fluorescence (XRF), scanning electron microscopy (SEM), SEM-energy dispersive X-ray (EDX), and transmission electron microscopy (TEM). The catalytic activities for higher alcohol synthesis from syngas, conducted at T = 300-360 °C, P = 5 MPa, GHSV = 760 L h^-1 (kg cat)^-1, and H₂/CO = 1.0, were investigated. Cat-TCA and Cat-AHM have shown a filamentous morphology with a strip axial arrangement and that a few longitudinal grooves and many irregular particles are distributed on the fiber surfaces. The degree of entanglement of the strip axial arrangement in AHM was found to be more than that in TCA, thus leading to form tangled MoS₂ slabs on AHM and long linear slabs on TCA with long rim sites. The obtained results revealed that the CO conversion increases in the order Cat-TCA < Cat-OBC-1 < Cat-DAC < Cat-AHM. Ethanol, propanol-1, and methanol are the most predominant alcohol products in the collected liquid products, with the byproducts containing mainly butanol-1, isobutanol, amyl alcohol, and isoamyl alcohol. Cat-DAC and Cat-OBC-1 show higher selectivity toward C₃₊, C₄₊, propanol-1, butanol-1, isobutanol, and amyl alcohol-1 than Cat-TCA and Cat-AHM. For powdered activated carbons, microporous catalysts inhibited isomerization because the catalyst that contains the highest micropores (Cat-DAC) produced a considerable amount of linear alcohols compared with Cat-OBC-1.

Isolation, molecular identification of lipid-producing Rhodotorula diobovata: optimization of lipid accumulation for biodiesel production

Background

The increased demand for oil and fats to satisfy the ever-increasing human needs has enhanced the research in this field. Single-cell oils or microbial lipids produced by oleaginous microorganisms are being utilized as an alternative to traditional oil sources. Oleaginous yeasts can accumulate lipids above 20% of their biomass when they are grown under controlled conditions.

Results

In the present study, sixty-five yeasts were isolated from different sources. Using Sudan Black B staining technique, five yeast isolates were selected. Under nitrogen-limited cultivation conditions, the Co1 isolate was the best lipid accumulation potential of 39.79%. Isolate (Co1) was characterized morphologically and identified using the ribosomal DNA internal transcribed spacers regions (rDNA-ITS) from their genomic DNA. The sequence alignment revealed a 99.2% similarity with Rhodotorula diobovata. Under the optimized conditions, Rhodotorula diobovata accumulated lipids up to 45.85% on a dry biomass basis. R. diobovata, when grown on different raw materials, accumulated lipid up to 46.68% on sugar beet molasses medium, and the lipid had a high degree of monounsaturated fatty acids which gives biodiesel better quality.

Conclusions

The data suggest that the potent oleaginous yeast, R. diobovata, together with the use of cheap feedstock raw materials such as sugar beet molasses, can be considered as a promising feedstock for biodiesel production.

Failure Mode and Effect Analysis (FMEA) may enhance implementation of clinical practice guidelines: An experience from the Middle East

RATIONALE, AIMS, AND OBJECTIVES

Implementation of clinical practice guidelines (CPGs) has been shown to reduce variation in practice and improve health care quality and patients' safety. There is a limited experience of CPG implementation (CPGI) in the Middle East. The CPG program in our institution was launched in 2009. The Quality Management department conducted a Failure Mode and Effect Analysis (FMEA) for further improvement of CPGI.

METHODS

This is a prospective study of a qualitative/quantitative design. Our FMEA included (1) process review and recording of the steps and activities of CPGI; (2) hazard analysis by recording activity-related failure modes and their effects, identification of actions required, assigned severity, occurrence, and detection scores for each failure mode and calculated the risk priority number (RPN) by using an online interactive FMEA tool; (3) planning: RPNs were prioritized, recommendations, and further planning for new interventions were identified; and (4) monitoring: after reduction or elimination of the failure mode. The calculated RPN will be compared with subsequent analysis in post-implementation phase.

RESULTS

The data were scrutinized from a feedback of quality team members using a FMEA framework to enhance the implementation of 29 adapted CPGs. The identified potential common failure modes with the highest RPN (≥ 80) included awareness/training activities, accessibility of CPGs, fewer advocates from clinical champions, and CPGs auditing. Actions included (1) organizing regular awareness activities, (2) making CPGs printed and electronic copies accessible, (3) encouraging senior practitioners to get involved in CPGI, and (4) enhancing CPGs auditing as part of the quality sustainability plan.

CONCLUSION

In our experience, FMEA could be a useful tool to enhance CPGI. It helped us to identify potential barriers and prepare relevant solutions.

Algal carbohydrates affect polyketide synthesis of the lichen-forming fungus Cladonia rangiferina

Lichen secondary metabolites (polyketides) are produced by the fungal partner, but the role of algal carbohydrates in polyketide biosynthesis is not clear. This study examined whether the type and concentration of algal carbohydrate explained differences in polyketide production and gene transcription by a lichen fungus (Cladonia rangiferina). The carbohydrates identified from a free-living cyanobacterium (Spirulina platensis; glucose), a lichen-forming alga (Diplosphaera chodatii; sorbitol) and the lichen alga that associates with C. rangiferina (Asterochloris sp.; ribitol) were used in each of 1%, 5% and 10% concentrations to enrich malt yeast extract media for culturing the mycobiont. Polyketides were determined by high performance liquid chromatography (HPLC), and polyketide synthase (PKS) gene transcription was measured by quantitative PCR of the ketosynthase domain of four PKS genes. The lower concentrations of carbohydrates induced the PKS gene expression where ribitol up-regulated CrPKS1 and CrPKS16 gene transcription and sorbitol up-regulated CrPKS3 and CrPKS7 gene transcription. The HPLC results revealed that lower concentrations of carbon sources increased polyketide production for three carbohydrates. One polyketide from the natural lichen thallus (fumarprotocetraric acid) also was produced by the fungal culture in ribitol supplemented media only. This study provides a better understanding of the role of the type and concentration of the carbon source in fungal polyketide biosynthesis in the lichen Cladonia rangiferina.

Analysis of fibronectin expression in the bilharzial granulomas and of laminin in the transformed urothelium in schistosoma haematobium infested patients

The bilharzial granulomas and urothelial transformation are common findings in Schistosoma haematobium infested patients. We hypothesize that the distribution of extrinsic (fibronectin, FN) and intrinsic basement membrane (BM) proteins (laminin, LN) is altered during the evolution of these lesions.

METHODS

To test this hypothesis, 70 cystectomy specimens, entailing variable associations of normal and dysplastic urothelium (all cases), and bilharzial granulomas were examined for FN and LN protein expression.

RESULTS

The biharzial granulomas were formed of admixture of CD3+T cells, CD68+histiocytes and CD220B cells. The CD3+T cells and and CD68+histiocytes were the predominant cell populations. Increased deposition of FN occurred with the evolution from cellular (loose fibrillary network, 20 cases) to fibrocellualr (dense fibrillary network, 30 cases) to fibrotic (tight conglomerates, 20 cases) granulomas. Alternatively, BM staining for LN was linear and continuous underlying normal and metaplastic urothelium. In dysplastic urothelium (20 cases), it showed breaks in continuity.

CONCLUSIONS

Alterations of FN and LN occur during the development of the bilharzial granuloma and urothelial transformation.

Seroprevalence of rubella among pregnant women in Khartoum state, Sudan

Rubella vaccine is not included in the Sudanese national immunization programme, and data on prevalence of rubella among women of childbearing age are inadequate. The objective of this cross-sectional study was to determine the seroprevalence of rubella among pregnant women in Khartoum state, Sudan. A total of 500 pregnant women who visited 7 antenatal clinics from November 2008 to March 2009 were examined for the presence of rubella IgG antibodies using ELISA. Rubella IgG antibodies were detected in 95.1% (95% Cl: 93.2%-97.0%) of women. This seroprevalence was significantly associated with education level, but not with age, residence area, occupation or parity. We presume this high seroprevalence indicates a high circulation of wild rubella virus in Khartoum state. Similar studies in other Sudanese states would be important for informing a decision to introduce rubella vaccine to Sudan.

Study on some factors affecting survivability of airborne fungi

The aim of the present study was to investigate the effect of some air pollutants and meteorological parameters on the survivability of airborne fungi. Fungi were collected by using a slit impactor sampler calibrated to draw 20 L/min, for 3 min. Nitrogen dioxide (NO(2)), sulfur dioxide (SO(2)), particulate matter (PM), relative humidity (RH %), temperature (T °C) and wind speed (WS) were also measured. Air samples were taken during the period from March 2006 to February 2007. Fungal concentrations ranged between 45 and 451 CFU/m(3) with an annual mean concentration of 216 CFU/m(3). The lowest fungal concentration was found in the summer, however the highest one was found in the autumn. NO(2,) SO(2) and PM averaged 83.66 μg/m(3), 67.01 μg/m(3), and 237.69 μg/m(3), respectively. T °C was positively and negatively correlated with Aspergillus (P = 0.000) and Penicillium (P = 0.007), respectively. RH% was positively correlated with total fungi (P = 0.001), Aspergillus (P = 0.002) and Cladosporium (P = 0.047). Multiple regression analysis showed that T °C and RH% were the most predicted variants. Non-significant correlations were found between fungal concentrations and air pollutants. Meteorological parameters were the critical factors affecting fungal survivability.

Chronic immune thrombocytopenia in a child responding only to thrombopoietin receptor agonist

Immune thrombocytopenia (ITP) is an acquired hematological disease in which the body produces antibodies against its own platelets leading to platelet destruction resulting in isolated thrombocytopenia. Childhood ITP may enter complete remission in the majority of cases within six months from diagnosis. However, 20-30% of affected children may develop chronic ITP (lasting for more than 12 months). First line treatment includes intravenous immunoglobulin (IVIG), corticosteroids or anti-D immunoglobulin. Second line treatment includes splenectomy, immunosuppressive therapy or Rituximab. Recently two thrombopoietin (TPO) receptor agonists (Romiplostim and Eltrombopag) are used to increase platelet count in refractory chronic ITP by increasing platelet production in bone marrow. Here is a case report on an 8 ½ -year-old boy with refractory chronic ITP who failed therapy with IVIG, corticosteroids, splenectomy and Rituximab. He showed excellent response to treatment with TPO receptor agonist (Romiplostim). His platelet count increased from less than 10 x10(3)/dl and maintained between 100x10(3)/dl to 200x10(3)/dl after few weeks of starting Romiplostim therapy.

Efficacies of artesunate plus either sulfadoxine-pyrimethamine or amodiaquine, for the treatment of uncomplicated, Plasmodium falciparum malaria in eastern Sudan

Artemisinin-based combination therapy (ACT) is increasingly being adopted as the first-line treatment for malaria in sub-Saharan Africa. In September-November 2005, in New Halfa, eastern Sudan, the efficacy of artesunate-sulfadoxine-pyrimethamine (AS-SP) for the treatment of uncomplicated, Plasmodium falciparum was compared with that of artesunate-amodiaquine (AS-AQ). The artesunate was given at 4 mg/kg. day on days 0-2, with either a single dose of SP (25 mg sulfadoxine/kg) given on day 0, or AQ, at 10 mg/kg. day, given on days 0-2. Eighty-two of the patients treated (40 given AS-SP and 42 given AS-AQ) completed the 28 days of follow-up. On day 3 all the patients were afebrile and only one patient, in the AS-AQ group, was still parasitaemic. AS-SP appeared slightly more efficacious than AS-AQ but the differences were not statistically significant. Only one patient (2.5%) given AS-SP but four (9.5%) of those given AS-AQ were initially considered to be late treatment and parasitological failures, with all other patients showing an adequate treatment response. The PCR-corrected frequencies of cure were 97.5% for AS-SP and 95.2% for AS-AQ (P>0.05). No gametocytaemias were observed during the follow-up and, although mild adverse effects (nausea, vomiting, abdominal pain, dizziness and/or rash) were detected in 14 patients, they occurred at the same frequency in each treatment arm. It therefore appears that the AS-SP and AS-AQ combinations were both effective and safe for the treatment of uncomplicated, P. falciparum malaria in eastern Sudan.

Biological control of bacterial spot of tomato caused by Xanthomonas campestris pv. vesicatoria by Rahnella aquatilis

Xanthomonas campestris pv. vesicatoria strain 2 was isolated from infected tomato seedlings grown in open field in Egypt. This strain produced irregular yellow-necrotic areas on tomato leaves and spotting of the stem. In an attempt to control this disease biologically, four experiments were conducted and tomato seedlings were pretreated, before the pathogen, with either of two antagonistic strains of Rahnella aquatilis through leaves, roots, soil or seeds. In all experiments, seedlings pretreated with R. aquatilis showed reduced susceptibility toward X. c. pv. vesicatoria. They also contained reduced protein concentration and showed reduced number of protein bands in SDS-PAGE analysis as well as increased fresh and dry weight relative to control seedlings inoculated with the pathogen only. This indicates that R. aquatilis reduced the deleterious effect and the stress exerted by X. c. pv. vesicatoria on tomato seedlings. Foliar application of R. aquatilis was the most effective method in disease reduction which could be attributed to the direct effect of the antagonistic bacteria on the pathogen. The highest amounts of fresh and dry weight were obtained from seed treatment, which might suggest that bacterial seed inoculation provides earlier protection than could be achieved with foliar, soil or root treatment.

Efficacies of chloroquine, sulfadoxine-pyrimethamine and quinine in the treatment of uncomplicated, Plasmodium falciparum malaria in eastern Sudan

The efficacies of several antimalarial drugs in the treatment of uncomplicated Plasmodium falciparum malaria were compared, during an open, randomized trial, in New Halfa, eastern Sudan. The 96 patients who completed the 28 days of follow-up were treated with chloroquine (N = 26), sulfadoxine-pyrimethamine (N = 38) or quinine (N = 32). No treatment failures were observed among the patients given sulfadoxine-pyrimethamine. Only 23.1% of the patients given chloroquine showed adequate clinical response, however, the rest showing early (15.4%) or, more frequently, late (61.5%) treatment failure. In terms of parasitological failure, 54.1% of the patients given chloroquine showed early RI resistance, 7.7% showed late RI, and 15.1% showed RIII. Most (90.6%) of the patients treated with quinine had adequate treatment responses, the rest having late treatment failures (and late RI). The frequency of treatment failure was significantly higher, however, among the patients given chloroquine than in the quinine-treatment arm. The present results and those of earlier investigations indicate that the problem of chloroquine resistance is worsening in eastern Sudan, and that the use of chloroquine as the first-line drug for the treatment of uncomplicated malaria in this area is now compromised. The response to quinine may also be faltering.

Characterization of two antagonistic strains ofRahnella aquatilis isolated from soil in egypt

In an attempt to obtain biological control agents for controlling bacterial spot of cucumber, over 250 bacterial strains were isolated from agricultural soil samples, collected from different localities in Giza Governorate (Egypt) and screened for in vitro antibiosis towards Xanthomonas campestris. Only 2 strains showed antagonistic activity. They and their culture filtrates restricted the growth of a number of G- and G(+)-indicator bacteria. On Chrome Azurol S agar, both strains exhibited a marked siderophore production. Biolog plates identified these strains as Rahnella aquatilis. Their characteristics were studied and compared with literature data on R. aquatilis. This antagonistic bacterium has not been previously isolated in Egypt.

Factors affecting variations in exposure to infections by Leishmania donovani in eastern Sudan

A cross-sectional survey was carried out in Gedaref state, eastern Sudan to investigate the prevalence of positive leishmanin skin tests and environmental factors related to Leishmania donovani infection. A total of 3835 people living in 11 villages in 3 regions were screened. Soil types and tree densities were determined in 33 villages inhabited by 44 different tribes. The highest rates of positive skin tests were in Rahad region (33.9%), Atbara (21.6%) and Gedaref (10.6%), with an average of 21.1% for the state. Risk of infection by L. donovani varied significantly between different tribes. Higher densities of Acacia and Balanites spp. trees were in Masaleet villages, suggesting that the relatively high risk of L. donovani exposure in this tribe is due to environmental factors.

A comparison of the physicochemical and immunological properties of the plant gum exudates of Acacia senegal (gum arabic) and Acacia seyal (gum tahla)

The physiochemical and immunological properties of three Sudanese gum arabic samples and four gum tahla samples (two Sudanese, one West African and one Tanzanian--Acacia seyal var. seyal) were compared. The optical rotation (ca -30 degrees) and rhamnose (12-14%), arabinose (24-29%), galactose (36-42%), glucuronic acid (16-17%), nitrogen (0.327-0.365%) and protein (2.16-2.41%) contents of the gum arabic samples were consistent with the FAO (1990) specification for Acacia gum. In contrast the gum tahla samples had positive [alpha]D values (+45 degrees to +54 degrees), lower rhamnose (3-4%) and higher arabinose (41-45%) contents and lower nitrogen (0.147-0.175%), and hence protein (0.97-1.15%), contents. All of the gum arabic samples precipitated with beta-glucosyl Yariv reagent and hence were shown to contain arabinogalactan-protein(s) (AGPs), whereas in all but one of the gum tahla samples AGPs were not detected. The strong interaction of gum tahla with a monoclonal antibody known to recognize arabinose residues present in AGPs and arabinogalactans (AGs) was consistent with the observed higher levels of arabinose present in the gum tahla samples relative to the gum arabic samples. The data presented confirm that there are a number of physicochemical and structural differences between gum arabic (A. senegal gum) and gum tahla (A. seyal gum), and that a quick and simple immunological technique (immunodot blots) using an antiAGP/AG monoclonal antibody (MAC 207) could be used to screen for the presence of gum tahla in gum arabic consignments.

Risk of thrombocytopenia in the infants of mothers with idiopathic thrombocytopenia

Twenty-nine of 27,662 pregnant women had autoimmune thrombocytopenia at the time of delivery at King Khalid University Hospital over 6 years starting June 1986. Twenty-six had idiopathic thrombocytopenic purpura (ITP), gave birth to 33 infants, of which 22 were by spontaneous vaginal delivery, eight by lower segment cesarean section, and two by forceps. Fourteen (44%) of the 32 living infants had platelets less than 150 x 10(9)/L and four (12.5%) had severe thrombocytopenia (platelets less than 50 x 10(9)/L). The mothers' platelets of less than 50 x 10(9)/L at delivery were found to be predictive of thrombocytopenia in their infants (P < 0.027), compared with mothers' platelet of more than 50 x 10(9)/L. Maternal treatment with prednisone did not seem to have significant effect on infants' platelets (P < 0.89). All infants with severe thrombocytopenia (less than 50 x 10(9)/L) at birth had ultrasound done and were found to be normal. We conclude that: (1) steroid given to pregnant women with ITP does not increase infants' platelet counts, (2) severe thrombocytopenia in the mothers (platelet counts less than 50 x 10(9)/L) is highly predictive of thrombocytopenia in their infants; (3) cesarean section should be limited to the mother with severe thrombocytopenia if fetal scalp platelets are less than 50 x 10(9)/L.