Colistin as A Good Monotherapy to Restrain the Pathogenicity of Acinetobacter baumannii In vivo and In vitro

  تعد بكتيريا Acinetobacter baumannii من احد مسببات الأمراض الانتهازية الرئيسية التي تقاوم العديد من المضادات الحيوية. الكوليستين هو مضاد حيوي يستخدم في الوقت الحاضر كطريقة  لمعالجة أخيرة للعزلات ذات المقاومة الشديدة. الغرض من هذه الدراسة هو التعرف على أهمية  جين LptD في الطبقه الدهنية LPS  من بكتريا A. baumannii ومعرفة دورها  الاساسي كعامل ضراوة.في الدراسة الحالية،  تم استخدام عزلتين من بكترياA.baumannii ، االعزلة المحلية HHR1 والعزلة العالمية ATCC 17904 ، وتم استخدام ثلاث انواع من المضادات الحياتية  (الكوليستين ،الريفامبيسين و  الفوسفوميسين كعلاج احادي او مزدوج خارج وداخل الجسم الحي.اظهرت النتائج أن A. baumannii HHR1 هي أكثر مقاومة لـ AMPs (Antimicrobial peptides) من السلالات العالمية ، تم ملاحظة ازدياد تأثير AMPs على A. baumannii بزيادة التركيز ووقت الحضانة ، كما تبين أيضًا أن AMPs تعتبر قاتله على بكتريا A. baumannii عند التركيز العالي (µg ml-12 ) في العلاج الأحادي و (1.5 ، 2 ) µg ml-1  في الدمج. علاوة على ذلك ، كانت حساسية العزلات متغايرة ، حيث اظهر الكولستين فعالية متميزة في تثبيط النمو البكتيري كعلاج احادي او عند المزج مع مضاد اخر.أظهرت النتائج أن التعبير الجيني لجينات lptD ، lptA للعزله المحلية أقل من العزلة القياسية بتركيز  2 µg ml-1 من الكوليستين ، بينما جين lptE كانت العزله القياسية  ذات  نمط تنظيم أعلى مما كان عليه في العزلة المحلية. علاوة على ذلك ، يؤثر الكوليستين على التصاق  A. baumannii على الخلايا الظهارية (A-549 خلية سرطان الرئة) ، وأظهر الكولستين تأثيرًا كبيرًا على نمو البكتيريا ، وتكاثر الخلايا ، عن طريق تقليل اعداد البكتيريا.        Acinetobacter baumannii  (A. baumannii) is a major opportunistic nosocomial pathogen, mostly resistant to several groups of antibiotics. Colistin is now used as a last-line treatment for isolates that are highly resistant. The purpose of this study is to identify the importance of LptD; which is involved in the translocation of LPS from the inner membrane to the outer membrane in compartment with LptA and LptC of A. baumannii and its indispensable role as a virulence factor, and the efficiency of colistin as a monotherapy. In the current research, two isolates of A.baumannii were used, the local isolate HHR1 isolated from urine sample and the global strain ATCC 17904, and three antibiotics (colistin, rifampicin and Fosfomycin) were used as a monotherapy and synergic therapy in vivo and ex vivo. The results demonstrated that A. baumannii HHR1 was more resistant to Antimicrobial peptides (AMPs) than the standard strains. The effect of AMPs  on A. baumannii was increased by increasing the concentration and the time of incubation, and also AMPs were shown to be lethal on A. baumannii growth spatially at high concentration (2 µg ml-1) in  monotherapy and (1.5, 2 µg ml-1) in synergic. The susceptibility of isolates towards antibiotics was variable, where colistin exerts significant growth had defect as a monotherapy and in combination with others. The results showed that the expression of lptD, lptA genes of A.baumannii HHR1 were  higher than of  the same genes in A.baumannii ATCC 17904 in the presence of 2 µg ml-1  colistin, while lptE gene of the A.baumannii ATCC 17904 showed an upregulation pattern  than in A.baumannii HHR1. Furthermore, colistin influences the adhesion ability of A. baumannii on epithelial cells (A-549 lung cancer cell) by reducing the number of cells, and thus could colistin be a good candidate for A. baunmannii treatment

Differentiated Stem Cells Derived from Rabbit Adipose Tissue Exhibited in ‎Vitro Adipogenesis and Osteogenesis

The multipotent characteristic of rabbit adipose-derived stem cells makes them available and ‎convenient sources for isolating mesenchymal stem cells. The aim of this study was to assess ‎the differentiation in rabbit adipose-derived stem cells pre-committed to produce several ‎mesenchymal lineages in response to inductive extracellular cues to multipotent stromal cells. ‎Three grams of adipose tissue was taken from a subcutaneous region of the nape of the neck ‎and was carefully isolated to obtain mesenchymal stem cells for expanded by fourth passage. In ‎the 4th passage, active growth of mesenchymal stem cells was observed. Furthermore, the ‎research demonstrated the inherent ability of rabbit MSCs to induce differentiation in ‎osteogenic and adipogenic lineages. These mesenchymal stem cells were successfully isolated ‎from adipose tissue which differentiated into either osteocytes or adipocyte-like cells after 21 ‎and 14 days of culturing in specific osteogenic and adipogenic media, respectively. The ‎remarkable differentiation potential of rabbit mesenchymal stem cells is indicated by ‎mineralized deposition to the osteocytes and lipid droplets accumulated in the cytoplasm lipid ‎vacuoles in the adipocytes‎

Evaluating the Activity of Ultrasound on Biofilm Formation by Acinetobacter baumannii isolated from clinical Specimens

Acinetobacter baumannii received attention for its multi-drug resistant associated with many severe infections and outbreaks in clinical environment. The aims of the study are to investigate the antibiotic susceptibility profile of clinically isolated A. baumannii, biofilm production, and the efficiency of Low Frequency Ultrasound (LFU) and honey to attenuate biofilm production. A total of 100 samples were taken from different sources from Baghdad hospitals. The susceptibility patterns revealed the percentage of pan drug resistant (PDR) isolates were 1.5 %, 72.7 % were extended drug resistant (XDR), 16.7 % were multidrug resistant (MDR), and 9.1 % were non MDR and sensitive to most antibiotics used. The ability to form biofilm was detected by crystal violet staining, and the results showed that 20% were strong biofilm, and 31.8% were moderate biofilm. The biofilm formation percentage was decreased using Low frequency ultrasound LFU and honey. Moreover, PCR results revealed that not all of them harbouring biofilm-related genes or integrons (bap, csuE, IntI-1, IntI-2), although, they are strong biofilm producers. These results conclude that low frequency ultrasound and chemical components of honey might be a good choice to restrain A. baumannii biofilm formation, and negative correlation between antibiotic resistance and biofilm ability. Running title: Antimicrobial drug resistance, Acinetobacter baumannii, biofilm inhibitio

Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).

Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)

Improved risk stratification of patients with atrial fibrillation: an integrated GARFIELD-AF tool for the prediction of mortality, stroke and bleed in patients with and without anticoagulation.

OBJECTIVES: To provide an accurate, web-based tool for stratifying patients with atrial fibrillation to facilitate decisions on the potential benefits/risks of anticoagulation, based on mortality, stroke and bleeding risks. DESIGN: The new tool was developed, using stepwise regression, for all and then applied to lower risk patients. C-statistics were compared with CHA2DS2-VASc using 30-fold cross-validation to control for overfitting. External validation was undertaken in an independent dataset, Outcome Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF). PARTICIPANTS: Data from 39 898 patients enrolled in the prospective GARFIELD-AF registry provided the basis for deriving and validating an integrated risk tool to predict stroke risk, mortality and bleeding risk. RESULTS: The discriminatory value of the GARFIELD-AF risk model was superior to CHA2DS2-VASc for patients with or without anticoagulation. C-statistics (95% CI) for all-cause mortality, ischaemic stroke/systemic embolism and haemorrhagic stroke/major bleeding (treated patients) were: 0.77 (0.76 to 0.78), 0.69 (0.67 to 0.71) and 0.66 (0.62 to 0.69), respectively, for the GARFIELD-AF risk models, and 0.66 (0.64-0.67), 0.64 (0.61-0.66) and 0.64 (0.61-0.68), respectively, for CHA2DS2-VASc (or HAS-BLED for bleeding). In very low to low risk patients (CHA2DS2-VASc 0 or 1 (men) and 1 or 2 (women)), the CHA2DS2-VASc and HAS-BLED (for bleeding) scores offered weak discriminatory value for mortality, stroke/systemic embolism and major bleeding. C-statistics for the GARFIELD-AF risk tool were 0.69 (0.64 to 0.75), 0.65 (0.56 to 0.73) and 0.60 (0.47 to 0.73) for each end point, respectively, versus 0.50 (0.45 to 0.55), 0.59 (0.50 to 0.67) and 0.55 (0.53 to 0.56) for CHA2DS2-VASc (or HAS-BLED for bleeding). Upon validation in the ORBIT-AF population, C-statistics showed that the GARFIELD-AF risk tool was effective for predicting 1-year all-cause mortality using the full and simplified model for all-cause mortality: C-statistics 0.75 (0.73 to 0.77) and 0.75 (0.73 to 0.77), respectively, and for predicting for any stroke or systemic embolism over 1 year, C-statistics 0.68 (0.62 to 0.74). CONCLUSIONS: Performance of the GARFIELD-AF risk tool was superior to CHA2DS2-VASc in predicting stroke and mortality and superior to HAS-BLED for bleeding, overall and in lower risk patients. The GARFIELD-AF tool has the potential for incorporation in routine electronic systems, and for the first time, permits simultaneous evaluation of ischaemic stroke, mortality and bleeding risks. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier for GARFIELD-AF (NCT01090362) and for ORBIT-AF (NCT01165710)

Two-year outcomes of patients with newly diagnosed atrial fibrillation: results from GARFIELD-AF.

AIMS: The relationship between outcomes and time after diagnosis for patients with non-valvular atrial fibrillation (NVAF) is poorly defined, especially beyond the first year. METHODS AND RESULTS: GARFIELD-AF is an ongoing, global observational study of adults with newly diagnosed NVAF. Two-year outcomes of 17 162 patients prospectively enrolled in GARFIELD-AF were analysed in light of baseline characteristics, risk profiles for stroke/systemic embolism (SE), and antithrombotic therapy. The mean (standard deviation) age was 69.8 (11.4) years, 43.8% were women, and the mean CHA2DS2-VASc score was 3.3 (1.6); 60.8% of patients were prescribed anticoagulant therapy with/without antiplatelet (AP) therapy, 27.4% AP monotherapy, and 11.8% no antithrombotic therapy. At 2-year follow-up, all-cause mortality, stroke/SE, and major bleeding had occurred at a rate (95% confidence interval) of 3.83 (3.62; 4.05), 1.25 (1.13; 1.38), and 0.70 (0.62; 0.81) per 100 person-years, respectively. Rates for all three major events were highest during the first 4 months. Congestive heart failure, acute coronary syndromes, sudden/unwitnessed death, malignancy, respiratory failure, and infection/sepsis accounted for 65% of all known causes of death and strokes for <10%. Anticoagulant treatment was associated with a 35% lower risk of death. CONCLUSION: The most frequent of the three major outcome measures was death, whose most common causes are not known to be significantly influenced by anticoagulation. This suggests that a more comprehensive approach to the management of NVAF may be needed to improve outcome. This could include, in addition to anticoagulation, interventions targeting modifiable, cause-specific risk factors for death. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

Detection of Antibiotics in Drinking Water Treatment Plants in Baghdad City, Iraq

Persistence of antibiotics in the aquatic environment has raised concerns regarding their potential influence on potable water quality and human health. This study analyzes the presence of antibiotics in potable water from two treatment plants in Baghdad City. The collected samples were separated using a solid-phase extraction method with hydrophilic-lipophilic balance (HLB) cartridge before being analyzed. The detected antibiotics in the raw and finished drinking water were analyzed and assessed using high-performance liquid chromatography (HPLC), with fluorometric detector and UV detector. The results confirmed that different antibiotics including fluoroquinolones and B-lactams were detected in the raw and finished water. The most frequently detected antibiotics were ciprofloxacin with highest concentration of 1.270 μg L−1 in the raw water of Al-Wihda plant, whereas the highest concentration of levofloxacin was 0.177 μg L−1, while amoxicillin was not detected in this plant. In contrast, ciprofloxacin was found in both raw water and finished water of Al-Rasheed plant and recorded highest concentration of 1.344 and 1.312 μg L−1, respectively. Moreover, the residual amount of levofloxacin in the raw water was up to 0.414 μg L−1, whereas amoxicillin was shown to be the most detectable drug in the raw water of Al-Rasheed plant, with a concentration of 1.50 μg L−1. The results of this study revealed the existence of antibiotic drugs in raw and finished water and should be included in the Iraqi standard for drinking water quality assessment

Practical Approach for Sand-Production Prediction during Production

Sand production becomes a serious problem during the life of a well in the Zubair reservoir. In addition to the costs associated with lost production, workover operations, and the repair of electrical submersible pumps (ESP), field operators also have to manage the separation and disposal of the sand produced with the oil. Reliable sanding prediction analysis thus provides a basis for designs that achieve appropriate sand management strategy for more than 350 wells in the field. In this study, sanding prediction analyses were conducted using a technique that combines easily measurable lab data, log data, and analytical calculations with empirical methods that are supported by the results from previously run rigorous and advanced numerical code. The application of this approach was not only able to provide results that closely matched field experience but was also able to predict correctly, to the year, the onset of sanding in wells. Using sanding analyses and sanding prediction results for the remaining life of the Zubair reservoir will have a significant impact on the economic revenues derivable from the reservoir. This study can be used in field management and workover planning to provide a cost-effective solution to the sanding problem