Sinteza i biološka evaluacija nekih pirimidina, pirimido[2,1-b][1,3]tiazina i tiazolo[3,2-a]pirimidin derivata

4,6-Diamino-1H-pyrimidine-2-thione (1) was used for the preparation of the pyrimidine derivatives 2-5. Compound 5 was cyclized to produce pyrimido[2,1-b][1,3]thiazine derivatives 6, which was condensed with p-chlorobenzaldehyde to give compound 7. The latter compound was reacted with hydroxylamine to give isoxazolo[4,5-d]thiazino[2,3-a]pyrimidines 8. Compound 8b was treated with 2-chloroethyl methyl ether to afford compound 9. Similarly, compound 3 was reacted with chloroacetic acid to give thiazolo[3,2-a]pyrimidine 10, which was condensed with p-chlorobenzaldehyde to give compound 11. Compound 11 was condensed with hydroxylamine to give isoxazolo[4,5-d]thiazolo[2,3-a]pyrimidine 12. Compound 12b was treated with 2-chloroethyl methyl ether to afford compound 13. The biological evaluation of some prepared products showed that many of them revealed promising antimicrobial activity.4,6-Diamino-1H-pirimidin-2-tion (1) upotrebljen je kao ishodni spoj u sintezi derivata pirimidina 2-5. Spoj 5 je cikliziran u pirimido[2,1-b][1,3]tiazin derivat 6, koji je kondenziran s p-klorbenzaldehidom u spoj 7. Produkt 7 je u reakciji s hidroksilaminom dao izoksazol[4,5-d]tiazino[2,3-a]pirimidin 8. Spoj 8b je u reakciji s 2-kloretil metil eterom dao spoj 9. Slično je spoj 3 reagirao s kloroctenom kiselinom i dao tiazol[3,2-a]pirimidin 10, koji je kondenziran s p-klorbenzaldehidom u produkt 11. Spoj 11 je kondenzacijom s hidroksilaminom dao izoksazol[4,5-d]tiazolo[2,3-a]pirimidin 12. Spoj 12b je s 2-kloretil metil eterom dao produkt 13. Biološka evaluacija pokazuje da neki od sintetiziranih produkata imaju antimikrobno djelovanje

Antimikrobno djelovanje nekih glukopiranozil-pirimidin karbonitrila i fuzioniranih pirimidinskih sustava

3-Amino-5-(4-chlorophenylamino)-4-cyanofuran-2-carboxamide (2) was used as the key molecule for preparation of various furo- pyrimidines 3-9 and formation of spiro-cycloalkane furopyrimidines 10, 11. Also, poly fused heterocyclic compounds 13-17 were prepared from compound 2. The synthesized compounds were screened for their antimicrobial activity.3-Amino-5-(4-klorfenilamino)-4-cijanofuran-2-karboksamid (2) upotrebljen je kao ključni spoj za pripravu različitih furo-pirimidina 3-9 i spiro-cikloalkane furopirimidina 10 i 11. Fuzionirani heterociklički spojevi 13-17 pripravljeni su također polazeći iz spoja 2. Sintetizirani spojevi ispitani su na antimikrobno djelovanje

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

Statistical factorial designs for optimum production of thermostable α-amylase by the degradative bacterium Parageobacillus thermoglucosidasius Pharon1 isolated from Sinai, Egypt

Abstract Background This study aimed to isolate potent thermophilic and amylolytic bacteria from a hot spring of Pharaoh’s bath, Sinai, Egypt, and screen its degradative activity. The amylolytic activity was further optimized using a statistical full factorial design followed by response surface methodology. Results A thermophilic bacterium was isolated from the hot spring of Pharaoh’s Bath, Sinai, Egypt. The isolate produced amylase, cellulase, and caseinase and was identified by 16S rRNA gene sequencing as Parageobacillus thermoglucosidasius Pharon1 (MG965879). A growth medium containing 1% soluble starch was found to optimize the amylase production. Dinitrosalycalic acid method (DNS) was used to estimate the amount of reducing sugar produced. Statistical full factorial and response surface designs were employed to optimize physical variables affecting the α-amylase production and determine the significant interactions of the studied variables during the fermentation process. According to the results obtained by the response optimizer, the maximum amylase activity reached 76.07 U/mL/ min at 54.1°C, pH 5.6 after 98.5 h incubation under aerobic conditions. Moreover, the produced enzyme was thermostable and retained most of its activity when exposed to a high temperature of 100°C for 120 min. Maximum enzyme activity was attained when the enzyme was incubated at 70°C for 30 min. Conclusions This is the first report of the production of thermostable α-amylase by the potent thermophilic Parageobacillus thermoglucosidasius. The enzyme endured extreme conditions of temperature and pH which are important criteria for commercial and industrial applications

Synthesis of Doped Sol-Gel Glasses as Adsorbents for Water Treatment

Doped sol-gel glasses of thiourea (THU), urea (U), n-propoylamine (PA), iso-propylamine (IPA), and 2-methoxyaniline (AN) were prepared and treated by two methods, thermal and microwave (MW) irradiation. The optical properties and particle sizes of the as-synthesized doped sol-gels and plain sol-gel (P) were measured. The sol-gels were then tested for their capacity to adsorb methylene blue dye (MB) and remove it from aqueous solutions. The highest removal efficiencies were exhibited by PA, IPA, and THU which were prepared by either the thermal or MW method. Amongst all the tested adsorbents, the thermally-prepared PA yielded the highest removal of over 95% for 12.5 mg/L of MB, and about 75% for 6.5 mg/L of MB. The MW-prepared PA showed the second highest removal efficiencies, while IPA, prepared thermally or by MW, showed comparable results to its PA counterpart. This behavior could be attributed to the higher basicity of aliphatic amines relative to aromatic amines, which resulted in increased interaction between the lone pair of electrons on amino nitrogen and MB. On the other hand, the interaction between U or THU and MB is suggested to have possibly occurred via electrostatic attraction or redox reaction between them. The characteristic Fourier Infrared (FTIR) spectra of PA and IPA before and after adsorption suggest that the C=O, N-H, and Si-OH groups, among others, could be involved in adsorption

Antimicrobial Profile of Actinomycin D Analogs Secreted by Egyptian Desert Streptomyces sp. DH7

Egyptian deserts are an underexplored ecological niche, especially the Sinai Peninsula. In our recent study, we explored this extreme environment and shed light on the bioactive capabilities of desert Actinobacteria isolated from Sinai. Fifty desert Actinobacteria were isolated from the Sinai desert using mineral salt media, basal media, and starch casein media. The filtrate of Streptomyces sp. DH 7 displayed a high inhibitory effect against multidrug-resistant Staphylococcus aureus (MRSA) strains. The 16S rDNA sequencing confirmed that isolate DH7 belongs to the genus Streptomyces. The NJ phylogenetic tree showed relatedness to the Streptomyces flavofuscus strain NRRL B-2594 and Streptomyces pratensis strain ch24. The minimum inhibitory concentrations against MRSA were 16 and 32 μg/μL. Chemical investigation of the ethyl acetate extract of Streptomyces sp. DH7 led to the isolation and purification of natural products 1–4. Structure elucidation of the purified compounds was performed using detailed spectroscopic analysis including 1 and 2D NMR, and ESI-MS spectrometry. To the best of our knowledge, this is the first report for the isolation of compounds 1–4 from a natural source, while synthetic analogs were previously reported in the literature. Compounds 3–4 were identified as actinomycin D analogues and this is the first report for the production of actinomycin D analogs from the Sinai desert with an inhibitory effect against MRSA. We indorse further study for this analog that can develop enhanced antimicrobial activities. We confirm that the desert ecosystems in Egypt are rich sources of antibiotic-producing Actinobacteria