Design, synthesis, and unraveling the antibacterial and antibiofilm potential of 2-azidobenzothiazoles: insights from a comprehensive in vitro study.

The present study reports the synthesis of 2-azidobenzothiazoles from substituted 2-aminobenzothiazoles using sodium nitrite and sodium azide under mild conditions. All the synthesized compounds were examined for their antibacterial activity against Gram (+) bacteria, Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 51299), Bacillus cereus (ATCC 10876) and Gram (-) bacteria, Escherichia coli (ATCC 10536), Pseudomonas aeruginosa (ATCC 10145), Klebsiella pneumonia (ATCC BAA-2146)and clinical isolates of Gram (+) Methicillin Resistant S. aureus (MRSA) and Multi Drug Resistant E. coli. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values by broth dilution method revealed that compound 2d exhibited significant antibacterial potential against E. faecalis and S. aureus with MIC of 8 µg/mL, while other synthesized compounds had only moderate effects against all the tested species. The compound significantly inhibited the biofilm formation of the bacterial strains below its MIC. The selective cytotoxicity of Compound 2d towards bacterial cells was evidenced on extended exposure of Human Embryonic Kidney-293 cell line to higher concentrations of the compound. Hence, the present study confirmed that compound 2d can be a potential drug candidate for future development as an antibacterial drug.

Clinical Relevance and Antimicrobial Profiling of Methicillin-Resistant Staphylococcus aureus (MRSA) on Routine Antibiotics and Ethanol Extract of Mango Kernel (Mangifera indica L.).

Methicillin-resistant Staphylococcus aureus (MRSA) is known for serious health problems. Testing new inexpensive natural products such as mango kernel (Mangifera indica L., Anacardiaceae) may provide alternative and economically viable anti-MRSA drugs. In the current study, we screened clinical isolates from Aseer Central Hospital, Saudi Arabia, during 2012-2017 for MRSA and tested an ethanolic extract of mango kernel for anti-MRSA activity. Brief confirmation of MRSA was performed by the Vitek 2 system, while antibiotic sensitivity of strains was tested for their clinical relevance. The In vitro disc diffusion method was used to test the anti-MRSA activity of the ethanolic mango kernel extract. The antimicrobial activity of mango kernel was compared to that of standard drugs (oxacillin and vancomycin). Of the identified 132 S. aureus strains, 42 (31.8%) were found to be MRSA and their prevalence showed a clear increase during the last two years (2016-2017; p < 0.001). MRSA strains showed 100% sensitivity to vancomycin, teicoplanin, linezolid, tetracycline, daptomycin, tigecycline, and tobramycin and 100% resistance to ampicillin and 98% to penicillin. The ethanolic extracts of mango kernel were found active against both S. aureus and the MRSA strains. Inhibitory activities (mean ± SE) were achieved at concentrations of 50 mg/mL (20.77 ± 0.61), 5 mg/mL (16.18 ± 0.34), and 0.5 mg/mL (8.39 ± 0.33) exceeding that of vancomycin (p=0.0162). MRSA strains were sensitive to mango kernel extracts when compared to vancomycin. Therefore, ethanolic extracts of mango kernel can be escalated to animal model studies as a promising leading anti-MRSA drug candidate and can be an economic alternative to high-priced synthetic antibiotics.

What accounts for ethnic differences in newborn skinfold thickness comparing South Asians and White Caucasians? Findings from the START and FAMILY Birth Cohorts.

OBJECTIVE: South Asians are a high-risk group for type 2 diabetes and coronary heart disease. We sought to determine ethnic differences in newborn adiposity comparing South Asians (SA) to White Caucasians (Whites). METHODS: Seven hundred ninety pregnant women (401 SA, 389 Whites) and their full-term offspring from two birth cohorts in Canada were analyzed. Pregnant women completed a health assessment including a 75-g oral glucose tolerance test to assess for dysglycemia. Birthweight, length, waist and hip circumference, and triceps and subscapular skinfold thickness (a surrogate measure of body adiposity) were measured in all newborns. Multivariate regression was used to identify maternal factors associated with newborn skinfold measurements. RESULTS: South Asian women were younger (30.1 vs 31.8 years, P<0.001), their prepregnancy body mass index was lower (23.7 vs 26.2, P<0.0001) and gestational diabetes was substantially higher (21% vs 13%, P=0.005) compared with Whites. Among full-term newborns, South Asians had lower birthweight (3283 vs 3517 g, P=0.0001), had greater skinfold thickness (11.7 vs 10.6 mm; P=0.0001) and higher waist circumference (31.1 vs 29.9 cm, P=0.0001) compared with Whites. Risk factors for newborn skinfold thickness included South Asian ethnicity (standardized estimate (s.e.): 0.24; P<0.0001), maternal glucose (s.e.: 0.079; P=0.04) and maternal body fat (s.e.: 0.14; P=0.0002). CONCLUSIONS: South Asian newborns are lower birthweight and have greater skinfold thickness, compared with White newborns, and this is influenced by maternal body fat and glucose. Interventions aimed at reducing body fat prior to pregnancy and gestational diabetes during pregnancy in South Asians may favorably alter newborn body composition and require evaluation.

Staff eye doses in a large medical centre in Saudi Arabia: are they meeting the new ICRP recommendations?

A 5-y retrospective analysis of the cardiology staff eye doses was performed on 34 staff from different categories (cardiologists, nurses and technologists) at King Faisal Specialist Hospital and Research Centre (KFSHRC) in Riyadh, Saudi Arabia. KFSHRC is a tertiary medical centre with 800-bed capacity having more than 5000 cardiac catheterisation procedures performed annually. The aim of the study is to derive staff doses to the lens of the eyes using the personal dose equivalent Hp(0.07) values from the annual TLD dose report for the years 2008-2012 and determine the category of staff with high estimated eye doses. The study also aims to investigate the causes for high doses and recommend dose-reduction techniques. The dose to the lens of the eye was estimated by using the ratio Hp(0.07)slab/Hlens of 1.1 where Hp(0.07) values are the reported doses read from TLD badge worn at the collar level. The average annual eye dose of each category for the 5-y monitoring period was determined. Cardiologists tend to receive higher doses than the nurses by a factor of 2-4 and can exceed 5 mSv y(-1). No correlation exists between the eye doses of nurses and the cardiologists. There is a need to use a conversion coefficient in terms of eye lens dose per dose-area product for faster estimation of eye lens doses. However, there is a limitation on the use of the conversion coefficient because it will depend on the clinical procedure and the X-ray tube angulation. Further investigation on this limitation is needed.

Candida and other yeasts of clinical importance in Aseer region, southern Saudi Arabia. Presentation of isolates from the routine laboratory setting.

OBJECTIVES: To isolate, identify, and determine the prevalence of Candida and other yeasts of clinical importance in Aseer region, Saudi Arabia. METHODS: This is a cross-sectional study involving retrospective analysis of 6100 samples submitted to the Microbiology Laboratory, Aseer Central Hospital, Abha, Saudi Arabia between 2011 and 2012, and prospective isolation and identification of 84 isolates recovered from various clinical specimens presented to the Microbiology Laboratory between 2012 and 2013 using the classic morphological schemes and the Vitek 2 automated system. RESULTS: The results of the retrospective analysis (2011-2012) indicated that of the 6100 various clinical specimens submitted to the routine microbiology analysis, 143 (2.35%) revealed the presence of Candida spp. The distribution of the 143 Candida spp according to specimens was as follows: urine 72%, sputum 10.5%, endotracheal tube 7%, blood 4.2%, catheter tip 2.1%, throat swab 2.1%, eye swab 0.7%, wound exudates 0.7%, and cerebrospinal fluid 0.7%. The results of the prospective study (2012-2013), which involved the identification of yeast recovered from 84 specimens indicated that Candida albicans 28.6% was the predominant species, followed by Candida parapsilosis 21.4%, Candida tropicalis 14.3%, and Candida lusitaniae 9.5%. CONCLUSIONS: Along with the commonly encountered Candida albicans, Candida parapsilosis, Candida tropicalis, and Candida lusitaniae were detected with significant rates. Many other Candida species and some other pathogenic yeasts have been detected for the first time in the region. Urinary tract samples were the main source of Candida species.

Identification of Acinetobacter clinical isolates by polymerase chain reaction analysis of 16S-23S ribosomal ribonucleic acid internal transcribed spacer.

BACKGROUND: The genus Acinetobacter is a diverse group of Gram-negative bacteria involve at least 33 species using the molecular methods. Although the genus Acinetobacter comprises a number of definite bacterial species, some of these species are of clinical importance. Therefore, it is of vital importance to use a method which is able to reliably and efficiently differentiate the numerous Acinetobacter species. OBJECTIVES: This study aims to identify Acinetobacter of clinical isolates from Assir region to the species level by 16S-23S intergenic spacers internal transcribed spacer (ITS) of ribosomal ribonucleic acid (rRNA). MATERIALS AND METHODS: Deoxyribonucleic acid extraction, polymerase chain reaction amplification of 16S-23S intergenic spacer sequences (ITS) was performed using the bacterium-specific universal primers. RESULTS: Based on the 16S-23S intergenic spacers (ITS) of rRNA sequences, all isolates tested were identified as Acinetobacter baumannii. The isolates shared a common ancestral lineage with the prototypes A. baumannii U60279 and U60280 with 99% sequence similarities. CONCLUSION: These findings confirmed 16S-23S rRNA ITS for the identification of A. baumannii of different genotypes among patients.

Radioactive waste handling and disposal at King Faisal Specialist Hospital and Research Centre.

King Faisal Specialist Hospital & Research Centre (KFSHRC) is the largest specialized medical center in Saudi Arabia. It performs highly specialized diagnostic imaging procedures with the use of various radionuclides required by sophisticated dual imaging systems. As a leading institution in cancer research, KFSHRC uses both long-lived and short-lived radionuclides. KFSHRC established the first cyclotron facility in the Middle East, which solved the in-house high demand for radionuclides and the difficulty in importing them. As both user and producer of high standard radiopharmaceuticals, KFSHRC generates large volumes of low and high level radioactive wastes. An old and small radioactive facility that was used for storage of radioactive waste was replaced with a bigger warehouse provided with facilities that will reduce radiation exposure of the staff, members of the public, and of the environment in the framework of "as low as reasonably achievable." The experiences and the effectiveness of the radiation protection program on handling and storage of radioactive wastes are presented.

Deriving staff and public doses in a PET/CT facility from measured radiation levels using thermoluminescent dosimetry.

The introduction of PET/CT at King Faisal Specialist Hospital and Research Centre for whole body and brain imaging has become favourable for diagnosis of cancer. There is no data available on the PET/CT dose to staff and members of the public for different activities of (18)F [fluorodeoxyglucose (FDG)] and for longer patient holding time. The study aims to determine and evaluate staff and public doses by using thermoluminescent dosemeters monthly readings for a 7-month deployment period and by using direct measurements of dose rates at 30 cm and 1 m distances from the patients after injection. The whole body doses per procedure and per administered activity of (18)F (FDG) were estimated. A dose map inside the PET/CT was generated to provide information of the dose levels in different locations. The Pearson correlation showed a strong correlation (r(2) = 0.71) between the dose per activity and the number of patients. Optimisation of radiation protection of staff and members of the public was investigated and recommendations were given.

Variation in radiation doses in paediatric cardiac catheterisation procedures.

Paediatric cardiac catheterisation involves diagnostic and therapeutic procedures that range from simple to complex and can subject paediatric patients to varying radiation doses. The study aims to determine the variation in entrance doses in patients in terms of dose-area product (DAP) values and to investigate the methods for optimising radiation protection. A total of 190 paediatric patients belonging to age groups 0, 1, 5 and 10 y who underwent diagnostic and six selected therapeutic procedures at King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia were included in the study. Therapeutic procedures include coarctation (COA), patent ductus arteriosus (PDA), radiofrequency ablation, pulmonary, embolisation and septostomy. Fluoroscopy and cine radiography were used in all procedures. Patient demography (weight, age, gender and height), radiographic technique factors, fluoroscopy and cine time, frame rate, and DAP values were taken from patients records. Effective doses for each procedure were estimated from the DAP values. The mean DAP per procedure were analysed for correlation with patient equivalent cylindrical diameter, weight, fluoroscopy time and number of frames. Factors influencing the variation in doses were investigated. Initial results show that PDA occlusion has the highest mean DAP value of 23.21 Gy-cm2, while the diagnostic and septostomy procedures have the lowest value of 7.77 and 6.95 Gy-cm2, respectively.

Patient parameters and other radiation safety issues in 131I therapy for thyroid cancer treatment.

Patients administered with a therapeutic dose of I for thyroid cancer treatment are potential sources of unacceptably high radiation exposure to other individuals, particularly the patient's immediate family members. Generally, patients are hospitalized until such time that the retained radioactivity in the body or the measured dose rate at 1 m from the patient's body surface fall to within acceptable levels. Patient release criteria are set to ensure that no individual shall be liable to receive exposures above the regulatory dose limit for the public or dose constraints for the patient's relatives or caregivers.

A study on the behaviour of TLD-100 glow peaks at extreme ambient temperatures in Riyadh, Saudi Arabia.

In this study, the temperature-induced variations in the TLD-100 response and the modifications in its glow peaks are investigated in real environmental exposure conditions in Riyadh, Saudi Arabia, where ambient temperatures during summer reach >45 degrees C and with relative humidity of <10%. Three groups of 12 TLD-100 cards in Harshaw type 8814 TLD cardholders were deployed as environmental dosemeters for a period of approximately 1 month for 12 consecutive months. One group was irradiated to 5 mGy 137Cs prior to deployment; another was irradiated to the same dose after deployment, while the last group was left unirradiated. Analysis of glow curves was done using commercially available glow curve deconvolution software (CGCD). Monthly variations in peak 3, 4 and 5 areas relative to the corresponding peak areas of a prompt glow curve are presented. Results of this study show good TL signal compensation between peaks 4 and 5 at all ambient temperatures encountered in this experiment, despite the observed individual variations experienced by each of these peaks. The sum of peak 4 and 5 areas is constant to within approximately 10%, for both pre- and post-irradiated dosemeters, during this 12-month cycle.

Glow curve evaluation in routine personal dosimetry.

The glow curve of LiF:Mg, Ti (TLD-100) has a well known and defined shape. Several factors, however, can distort the glow curve shape and can lead to incorrect dosimetry. Only proper evaluation of glow curves, either by visual inspection or computerized method, can detect these anomalies. Visual observation is riot only tedious and time consuming but may also be susceptible to human errors. The usefulness of a commercially available glow curve analysis software during quality control testing of thermoluminescence dosimetry cards is discussed. The long-term stability of the thermoluminescence dosimetry reader is also investigated using this software. Various types of glow curve anomalies encountered during routine personal dosimetry practice are presented.

Statistical analysis of historical occupational dose records at a large medical center.

Routine monitoring of occupational radiation exposure is done primarily to demonstrate compliance with dose limits. Statistical analysis of past and present dose records provides a useful tool in the management of institutional radiation safety programs. In this study, a statistical analysis of annual dose records from 1985-1999 from a large tertiary care medical center with a cyclotron and radiopharmaceutical production facility is performed. A total of 6,089 annual dose records, categorized into ten occupational groups, were included in the analysis. Dose distribution is skewed, with 85% of workers receiving an annual dose of less than 1.0 mSv, while 1.3% have doses > or =10 mSv. The mean annual dose of all monitored workers during this 15-y period ranged from 0.5 to 1.2 mSv. Large variation in the mean annual dose exists among the different occupational groups. Four occupational groups were identified as relatively highly exposed, namely cyclotron and radiopharmaceutical production, cardiac catheterization, nuclear medicine, and diagnostic radiology. These four occupational groups also showed different trends in the mean annual dose. A correlation study showed that total annual collective dose has no linear association with the number of monitored workers, the number of measurably exposed workers, or the number of workers with annual dose between 0.1 to <10 mSv. Moderate correlation (r = 0.64) was observed between the annual collective dose and the collective dose of workers with an annual dose between 0.1 to <10 mSv. A strong and significant correlation (r = 0.95) exists between the total annual collective dose and both the number of workers with annual dose of > or =10 mSv and the corresponding collective dose due to these highly exposed workers. Although the fraction of these highly exposed workers is small (about 1%), they have a significant impact on the total collective dose and their contribution can be as high as 50%. Workers with annual dose of > or =10 mSv tend to concentrate in a few identified occupational groups and not across all occupational groupings. The cyclotron and radiopharmaceutical production department is of particular concern due to its high individual dose levels and increasing mean annual dose trend for the last 5 y. Radiochemists and cyclotron engineers tend to receive an annual dose exceeding the dose limit. A plot of the collective dose of highly exposed workers vs. the total collective dose shows that if a dose constraint of 10 mSv is imposed on highly exposed occupational groups, the total collective dose is expected to be about 200 person-mSv.

Differential display analysis of mRNAs in chronic myelogenous leukaemia.

Analysis of expressed mRNAs with differential display-polymerase chain reaction (DD-PCR) is a powerful tool for the characterization of genes involved in malignant pathways and might identify markers for different phases of chronic myelogenous leukaemia (CML). We examined the presence of BCR-ABL transcripts in 25 CML patients in either the chronic phase or blast crisis. We then analysed the expression of leukocytic RNA transcripts in CML phases. DD-PCR technique was used to examine CML cases with BCR-ABL in comparison with CML cases lacking detectable BCR-ABL transcripts. Our results support the use of differential display not only for characterization of the CML differentially expressed genes but also to locate patterns that can be implemented as valuable fingerprints for each phase of CML.

Differential display analysis of mRNAs in chronic myelogenous leukaemia

Analysis of expressed mRNAs with differential display-polymerase chain reaction [DD-PCR] is a powerful tool for the characterization of genes involved in malignant pathways and might identify markers for different phases of chronic myelogenous leukaemia [CML]. We examined the presence of BCR-ABL transcripts in 25 CML patients in either the chronic phase or blast crisis. We then analysed the expression of leukocytic RNA transcripts in CML phases. DD-PCR technique was used to examine CML cases with BCR-ABL in comparison with CML cases lacking detectable BCR-ABL transcripts. Our results support the use of differential display not only for characterization of the CML differentially expressed genes but also to locate patterns that can be implemented as valuable fingerprints for each phase of CML

Nasosinus aspergillosis in Sudanese patients: clinical features, pathology, diagnosis, and treatment.

OBJECTIVE: The objective of this study was a prospective analysis of the clinical features, pathology, diagnosis, and treatment of patients treated between 1993 and 1996 for nasosinus aspergillosis in the Sudan. METHOD: Clinical examinations and laboratory tests for serologic, mycologic, and histologic analysis were conducted on all patients, as were radiologic and computerized tomographic studies when external swelling of any of the paranasal sinuses was evident. RESULTS: The age group 11 to 50 years were predominantly affected, with a peak in those aged 21 to 30 years. Females were affected more often than were males. The clinical features were mainly nasal polyposis, external swelling of the ethmoid sinus medial to the inner canthus, or maxillary cheek swelling and/or proptosis. In the paranasal sinuses, the ethmoids were the most frequently affected. Intracranial extension of the disease occurred in two patients. Serologic examinations and mycological cultures showed more incidence of positive results than did histopathology. Aspergillus flavus was grown in all the positive mycologic cultures except one, where Aspergillus niger was grown. The treatment was mainly surgical, supplemented by an antifungal drug (itraconazole). The incidence of recurrence was 9.3%, and it was noticed that the recurrence occurred in those patients who were not taking their medicines regularly. CONCLUSION: Nasosinus aspergillosis is a common disease in Sudan. Nasal polyposis is the commonest mode of clinical presentation. Serology and mycologic cultures are quite helpful in the diagnosis. Surgical and medical treatment are complementary of each other.

Mixed ligand complexes of benzimidazole and pyrimidine hydroxy azo dyes with some transition metals and glycine, dl-alanine or dl-leucine.

The overall formation constants of 1:1:1 ternary complexes of Cu(II), Zn(II), Cd(11) with glycine, dl-alanine or dl-leucine as primary ligands and o-hydroxyphenylyazo derivatives of 2-cyanomethyl benzimidazole (ABI) and barbituric acid (ABA) as secondary ligands have been investigated potentiometrically in 40% (v/v) EtOH. Formation constants of binary systems were also determined under the same experimental conditions (37 degrees C and mu=0.15 mol dm(-3)). The stability of ternary complexes have been quantitatively compared with those of the corresponding binary complexes in terms of the parameters DeltalogK, logX and logX'. The data were interpreted on the basis of statistical considerations and the nature of complexes. The concentration distribution of various species formed in solution was evaluated. The Cu(II) complexes have been synthesized and the coordination sites of the ligands were characterized by means of IR spectroscopy.