Aberrant DNA methylation has been firmly established as a factor contributing to the pathogenesis of colorectal cancer (CRC) via its capacity to silence tumour suppressor genes. However, the methylation status of multiple tumour suppressor genes and their roles in promoting CRC metastasis are not well characterised.CPEB1 (the gene encoding cytoplasmic polyadenylation element-binding protein 1), a candidate CRC tumour suppressor gene, using The Cancer Genome Atlas (TCGA) database and validated these results in both CRC cell lines and cells from Han Chinese CRC patients (n = 104). The functional role of CPEB1 in CRC was examined in experiments performed in vitro and in vivo. A candidate transcription factor capable of regulating CPEB1 expression was predicted in silico and validated by luciferase reporter, DNA pull-down, and electrophoretic mobility shift assays.We explored the methylation and expression profiles of CPEB1 in CRC tumour tissues were revealed by TCGA database. We also identified a significant inverse correlation  between promoter methylation and CPEB1 expression. We validated these results in CRC samples and two CRC cell lines. We also demonstrated that up-regulation of CPEB1 resulted in significantly decreased tumour growth, migration, invasion, and tumorigenicity and promoted tumour cell apoptosis both in vitro and in vivo. We identified the transcription factors CCAAT enhancer-binding protein beta (CEBPB) and transcription factor CP2 (TFCP2) as critical regulators of CPEB1 expression. Hypermethylation of the CPEB1 promoter resulted in a simultaneous increase in the capacity for TFCP2 binding and a decreased likelihood of CEBPB binding, both of which led to diminished expression of CPEB1.Hypermethylation and decreased expression of CPEB1 in CRC and found that hypermethylation of the CPEB1 promoter may lead to diminished expression due to decreased chromatin accessibility and transcription factor binding. Collectively, these results suggest a potential role for CPEB1 in the diagnosis and treatment of CRC.Our results identified a novel tumour-suppressive role of The online version contains supplementary material available at 10.1186/s13148-021-01071-z. Colorectal cancer (CRC) is the third most common cancer diagnosed and the second leading cause of cancer-related deaths in the USA , 2. ReceDNA methylation is a form of epigenetic modification that has been identified as critical for numerous physiological processes, including embryonic development , 7, histCPEB1) encodes a sequence-specific RNA-binding protein that regulates mRNA polyadenylation and translation [SIRT1 mRNA (encoding Sirtuin 1), thereby controlling the length of the poly(A) tail and suppressing its capacity to mediate cancer cell stemness both in vitro and in vivo [CPEB1 in the development of gastric cancer [CPEB1 and its methylation status in CRC remains unclear. In this study, we screened The Cancer Genome Atlas (TCGA) database to determine the methylation status and expression levels of CPEB1 in CRC. We validated these findings using targeted bisulfite sequencing to evaluate CPEB1 expression in tumour and para-tumour tissues collected from Han Chinese CRC patients. Furthermore, to confirm the role of CPEB1 in the development of CRC, we performed gain- and loss-of-function experiments to determine the effects of CPEB1 expression on cell proliferation, migration, invasion, and apoptosis both in vitro and in vivo. Finally, we verified promoter hypermethylation as the underlying cause of CPEB1 down-regulation using dual-luciferase reporter, chromatin immunoprecipitation (ChIP), DNA pull-down, mass spectrometry, and electrophoretic mobility shift (EMSA) assays.Cytoplasmic polyadenylation element-binding protein 1  of the transcription start site  were significantly hypermethylated in CRC tumours compared to the para-tumour tissue , which is a region close to the CPEB1 promoter (chr15:83316688–83316747), in CRC tumours than that in the accompanying para-tumour tissues  and specificity (96%) with an area under the receiving operator characteristic curve (AUC) of 0.88. Taken together, these results suggest that hypermethylation of CPEB1 might be developed as a potential diagnostic biomarker for CRC . We found significantly decreased CPEB1 promoter methylation in cells treated with DAC  resulted in significant increases in both CEPB1 mRNA and CEPB1 protein  or pcDNA3.1 (pcDNA3.1 group) were inoculated into BALB/c nude mice. The mice were sacrificed 36 days later and tumour volumes and wet weights were recorded. The tumours of the mice in the CPEB1 group were visibly smaller and of significantly smaller volume than those in the pcDNA3.1 and control groups , and E-cadherin in mouse tumour tissues by immunohistochemistry (IHC) and Western blotting (WB). We found that levels of immunoreactive Ki67 and MMP-9 proteins were diminished in tumours isolated from the CPEB1 group. By contrast, the levels of E-cadherin, a signal biomarker for epithelial–mesenchymal transition, were significantly increased in the CPEB1 group , GATA-binding factor 2 (GATA2), and tumour protein P53 (TP53)  substantially reduced the transcriptional activation of CPEB1 by CEBPB. These results indicated that the identified TF-binding region is essential for CEBPB-mediated activation of CPEB1 expression. In contrast to our findings for CEBPB, neither GATA2 nor TP53 could enhance the transcriptional activity of CPEB1  resulted in a significant decrease in luciferase activity. These results suggest that hypermethylation of the CEBPB-binding site could inhibit CPEB1 expression via interference with the recruitment of CEBPB to the CPEB1 promoter region  experiments to explore TF binding to the hypermethylated BPB Fig. a, b. We bes Fig. c. These CPEB1 probe using MS. We identified 236 candidate binding proteins in this experiment . The samples were obtained from the Department of General Surgery in Affiliated Hospital of Nantong University. Tumours were classified according to Tumour Node Metastasis (TNM)/Union for International Cancer Control (UICC) criteria following histopathological examination. The SW480, DLD1, and HCT116 cell lines were purchased from the Cell Bank of the Type Culture Collection of Chinese Academy of Sciences . The SW480 cells were cultured in Dulbecco’s modified Eagle’s medium (DMEM) with high glucose . The HCT116 cells were grown in McCoy’s 5A medium , supplemented with 10% fetal bovine serum  at 37 °C in 5% CO2. The full-length cDNA of CPEB1 (NM_030594.4) was cloned in the pcDNA3.1-EGFP (enhanced green fluorescent protein) vector to create the pcDNA3.1-CPEB1 overexpression vector. This vector was transfected into cells using Lipofectamine 2000 . 5-Aza-2′-deoxycytidine  was used for DNA demethylation as previously described [We collected the pairs of tumour tissue specimens and their corresponding para-tumour tissues  from Han Chinese patients diagnosed with CRC  at each CpG site was calculated based on the hypermethylated (M) and non-methylated (U) intensities as shown:Publicly available high-throughput DNA methylation microarray data (Illumina Human Methylation 450 K) of 387 CRC tumours and 45 samples of para-tumour tissue were obtained from the TCGA database (level-3). We identified nine candidate CpG sites within the β values calculated for CRC tumours and para-tumours were compared at each candidate CpG site. The mean methylation level of the CpG sites for each tissue sample was calculated as overall CPEB1 methylation. We then compared mean methylation levels of individual CRC tumours and para-tumours.The CPEB1 upstream region using next-generation sequencing (NGS). The amplified DNA fragments were sequenced by Illumina Hiseq 2000 . To verify the robustness of our methodology, we also examined the methylation status of the SEPTIN9, a gene known to be hypermethylated in CRC tissues  for each CpG site was calculated according to the number of reads (C or T) detected at each CpG site.To validate these findings, we extracted DNA samples from both tumour and paired para-tumour tissue which was subjected to bisulfite conversion. After careful evaluation of the CG percentage, poly(T), and single-nucleotide polymorphisms (SNPs) in the potentially differentially methylated regions (DMRs), we designed primers to detect the methylation of CPEB1. Overall methylation of CPEB1 was compared in both CRC tumours and their associated para-tumour tissue. The methylation rate  for each CpG site and for each sample determined in the validation stage is shown in Additional file Similarly, the mean methylation rate at each of these CpG sites in each sample was considered as the overall methylation of ACTB (encoding β-actin) and GAPDH served as internal references.Total RNA from CRC tissues and cell lines was isolated with TRIzol  following the manufacturer’s instructions. First-strand complementary DNA (cDNA) was synthesised from 1 μg total RNA using an M-MLV Reverse Transcriptase Kit . Real-time quantitative PCR was performed on an Applied Biosystems 7500 real-time PCR system  with SYBR green I dye . The expression levels of SW480 and HCT116 cells transfected with pcDNA3.1-CPEB1 and pcDNA3.1-EGFP vector-only control were incubated for 0, 24, 48, and 72 h in 96-well plates at 4,000 cells/well. Cell proliferation was detected by adding 10 µL CCK-8 solution  to each well followed by the optical density (OD 450 nm) measurements 3 h later using a microplate reader (Thermo Fisher Scientific).Cells were seeded into 24-well ultra-low attachment round-bottom plates  at a density of 100 cells per well in cell culture medium together with pcDNA3.1-CPEB1 and pcDNA3.1-EGFP vectors, respectively, and cultured for 14 days. Wells were then washed twice with phosphate-buffered saline (PBS), fixed for 15 min with 500 μL 4% paraformaldehyde, and stained with Giemsa dye for 10 min. The number of violet-stained cell spheres (nb: only cell spheres with > 10 cells were included) was determined in each well. The efficiency of cell colony formation was calculated as:5 cells/mL) that were transfected with pcDNA3.1-CPEB1 or pcDNA3.1-EGFP or mock-transfected with medium alone were added to the interior of the inserts in 200 μL serum-free medium. Five hundred μL of medium containing 20% FBS was added to the lower chamber followed by incubation at 37 °C in 5% CO2 for 24 h. Invasive cells detected on the lower surface of the membrane by staining with 0.1% crystal violet for 10 min were photographed. The number of invasive cells was calculated from images photographed at high magnification (400-fold). Relative invasion was defined as follows:A cell invasion assay was performed using an invasion chamber  in a 24-well tissue culture plate with 12-cell culture inserts. Suspensions of cells (10t = 0 h). Cells were incubated for an additional 24 and 48 h; the distances between the edges of the gap distance were assessed at these times to determine the rate of wound healing. Migration distance = gap distance at T0—gap distance at Tx (Tx = 24 h or 48 h). The gap distance was measured using ImageJ software (v1.53c). The wound width (%) was calculated as follows:Cells were seeded into a six-well tissue culture plate at a density that will permit them to reach 70%–80% confluence after 24 h of growth. The monolayer was scratched gently and slowly across the centre of the well with a 200-µL pipette tip. After scratching, the well was gently washed twice with tissue culture medium to remove the detached cells, and the distance between the two edges of the gap was measured . This was followed by the addition of 5 µL of Annexin V-APC (KeyGen) and 5 µL of the counterstain, 7-amino actinomycin D (7-AAD). The mixture was incubated at room temperature for 10 min in the dark, followed by quantitative analysis of apoptosis using a FlowSight flow cytometer .Cells were removed from tissue culture plates with trypsin and washed twice in ice-cold PBS. A total of 5 × 10CPEB1. The TF-binding regions were predicted for each factor within the upstream region of CPEB1. We then constructed wild-type and the mutant fragments of these regions for use in the dual-luciferase assay  to generate CPEB1-WT and CPEB1-Mut, respectively. The sequences of all construct inserts were verified by Sanger sequencing. The full-length cDNAs of these three TFs were cloned individually into the pcDNA3.1 expression vector to generate pcDNA3.1-CEBPB, pcDNA3.1-GATA, and pcDNA3.1-TP53, respectively. HCT116 cell cultures plated on 24-well plates were transfected individually with each of the TF expression vectors (0.81–1.07 μg/μL) together with wild-type pGL3-CPEB1 (1.64–2.01 μg/μL) or mutant pGL3-CPEB1 (1.30–1.71 μg/μL) using Lipofectamine 2000. In each transfection, 0.2 μg/μL of a pRL-TK vector (Renilla luciferase vector) was used to normalise the transfection efficiency. The pGL3-basic + pcDNA3.1 group served as a negative control.A dual-luciferase reporter assay system was purchased from Promega, USA. Three TFs  were identified as candidate transcriptional regulators of CPEB1 promoter region cloned into the pCpGL-basic vector), 200 ng of mutant pCpGL-CPEB1, or 200 ng of hypermethylated wild-type and mutated pCpGL-CPEB1 using Lipofectamine 2000. The pCpGL-basic vector engineered as devoid of CpG sites was a gift from Professor M. Wang, Soochow University, China. The pCpGL-CPEB1 reporter vector was hypermethylated with M.SssI (CpG) methyltransferase as per the manufacturer’s instructions (Thermo Fisher Scientific). In each transfection, 40 ng of a pRL-TK vector was used to normalise the transfection efficiency. Transfection with each of the pCpGL-basic reporter vectors together with each of the pcDNA3.1 expression vectors served as negative controls. The relative luciferase activity in each group was calculated as follows:A dual-luciferase reporter assay was also performed to determine whether hypermethylation at the predicted binding site for CEBPB had an impact on the binding interaction. HCT116 cells plated on 24-well plates were transfected with 160 ng of the pcDNA3.1-CEBPB expression vector and 200 ng wild-type pCpGL-CPEB1 , and PR3. Moreover, to identify the core TF-binding region by real-time quantitative PCR, we divided the core TF-binding region (PR2) into three smaller parts: PCR1, PCR2, and PCR3  assay was performed as previously described . BrieflyCR3 Fig. f. DNA puCPEB1 promoter region was amplified by PCR using a 5′-biotin-labelled primer  at a final concentration of 1% . Protein quantification was determined using the bicinchoninic acid (BCA) method (Beyotime). A synthetic 5′-end biotin-labelled probe that was consistent with the TF-binding sequence was prepared. The 5′-end biotin-labelled probe, an unlabelled specific competitive probe, and the non-specific competitive mutation probe were generated by GeneCreate Biological Engineering Co  as previously described . The seqTotal protein was extracted from cells and tissues using radioimmunoprecipitation (RIPA) lysis buffer  and quantitated using a BCA protein assay  as previously described . ProteinIHC staining score = IHC staining intensity score × score based on the number of positively stained tumour cells.n = 4 per group; Nantong University Laboratory Animal Center, China) were anaesthetised via inhalation of a mixture of isoflurane/propylene glycol. HCT116 cells transfected with recombinant plasmid constructs containing pcDNA3.1-CPEB1 or pcDNA3.1 were injected subcutaneously into the back of each mouse (2.0 × 106 cells in 200 μL PBS). The tumour sizes were assessed every 3 days by measuring in two dimensions; tumour volumes were estimated as the volume = (tumour length) × (tumour width)2/2. Mice were killed 36 days after implantation, and the tumours were collected and weighed. Slides were prepared and stained with hematoxylin and eosin (H&E). Levels of immunoreactive CPEB1, Ki67, MMP-9, and E-cadherin were determined by WB and IHC assays.All animal experiments were reviewed and approved by the Institutional Animal Care and Use Committee (IACUC) of Affiliated Hospital of Nantong University. Four male nude BALB/c mice at 5 weeks of age  correction was used for multiple test corrections, as applicable. The bottoms, middles, and tops of the boxes in box-and-whisker plots represent the 25th (Q1), median (Q2), and 75th percentile (Q3), respectively.Statistical assessments of differential DNA methylation and gene expression in CRC tumours and para-tumour tissue were performed using R (v3.6.3). All data from the functional experiments are shown as the mean ± standard deviation (SD). A value of Q3–Q1.The upper and the lower whiskers shown in the boxplots were calculated as follows:CPEB1, a putative TSG in CRC. The functional characterisation presented in this study confirmed the CRC tumour suppressor function of the CPEB1 gene. We found that overexpression of CPEB1 in CRC cell lines suppressed viability, colony formation, cellular invasion, and migration. CPEB1 overexpression also resulted in the increased capacity for cell transformation, larger tumour volumes, and increased rates of tumour cell apoptosis in experiments performed both in vitro and in vivo. Furthermore, we found the TF, CEBPB could bind to the core promoter region of CPEB1 and thereby regulate gene transcription. The hypermethylated form of the CPEB1 promoter found in CRC cells did not support CEBPB binding, although this epigenetic modification facilitated interactions with TFCP2. These interactions resulted in diminished expression of CPEB1 and enhanced CRC tumorigenesis and metastasis (Fig. Genome-wide alterations in DNA methylation have been widely reported in CRC in association with tumorigenesis and metastasis. However, the DNA methylation status of numerous TSGs and the contributions of hypermethylation to the pathogenesis of CRC remain largely unknown. Our study examined the hypermethylation status and expression of sis Fig. .Fig. 7A CPEB1 played a major role in tumour suppression via its capacity to maintain p53 mRNA polyadenylation and translation [p53 gene [CPEB1 has also been identified as a participant in the p53-mediated senescence of glioma cells [CPEB1 may also inhibit glioblastoma growth via its capacity to promote poly-A tail elongation and translation of the cell cycle inhibitor, p27 [CPEB1 might also target the 3′-UTR of SIRT1 to suppress the growth of hepatic carcinoma [CPEB1 in CRC has not been well characterised. Moreover, although previous studies have identified components of the CPEB1 downstream signalling pathways involved in tumour suppression, the corresponding upstream regulatory events remain undefined. In this study, we used a multifaceted experimental approach to explore the molecular mechanisms employed by CPEB1 as a TSG in CRC. Of note, we have demonstrated that CPEB1 suppression was associated with CRC malignant transformation and that this role is dependent on hypermethylation of the TF-binding site in its promoter region. Collectively, our results suggest a role for demethylation drugs as a future therapeutic approach to CRC.Results from previous studies revealed that nslation  and thusp53 gene . CPEB1 hma cells . Of notetor, p27 . CPEB1 marcinoma . HoweverTFCP2/TFCP2L1/UBP1 TF subfamily is involved in various aspects of cancer development [TFCP2 may also promote cervical carcinogenesis and CRC [TFCP2 was identified as involved in the epithelial-mesenchymal transition and might also enhance angiogenesis [TFCP2 can also act as a TSG, as exemplified by its capacity to inhibit melanoma growth [CPEB1 promoter and can suppress CPEB1 transcription. Interestingly, TFCP2 binds to the methylated upstream region of CPEB1; this suggests that TFCP2 might be a novel DNA methylation reader. However, the conclusion was based on only the in vitro studies only. Future in vivo experiments focused on the role of TFCP2 in CPEB1 regulation and CRC metastasis might provide important verification of this finding.The TF, TFCP2, plays a crucial role in cancer incidence and development . The TFCelopment , includi and CRC . TFCP2 wogenesis . Nonethea growth . These cCPEB1 upstream region activated CPEB1 transcription. Moreover, we demonstrated that hypermethylation of the CPEB1 promoter region resulted in significantly diminished CEBPB binding of CEBPB to its DNA recognition elements, thereby leading to diminished expression of CPEB1. These results suggest that diminished capacity for CEBPB bindings may be an important mechanism that contributes to decreased CPEB1 expression in CRC.TFs could modulate the expression of target genes and play a key role in tumour development, differentiation, and metastasis , 34. MetCPEB1 that was associated with its diminished expression in CRC tumours compared to para-tumour tissues. We identified CEBPB and TFCP2 as two critical TFs contributing to CPEB1 regulation. The epigenetic modifications of CPEB1 and subsequent transcriptional changes contribute significantly to CRC tumorigenesis and metastasis. Collectively, these results suggest that the development of CPEB1 as a candidate biomarker and molecular target for CRC treatment is a subject worthy of further consideration.In summary, our findings revealed hypermethylation within the upstream regions of Additional file 1. Supplementary Results and Tables about this study.Additional file 2. The excel of the methylation level for each sample in the validation dataset about this study.


The integral collection of information such as strains, cracks, or temperatures by ultrasound offers the best prerequisites to monitor structures during their lifetime. In this paper, a novel approach is proposed which uses the collected information in the coda of ultrasonic signals to infer the condition of a structure. This approach is derived from component tests on a reinforced concrete beam subjected to four-point bending in the lab at Ruhr University Bochum. In addition to ultrasonic measurements, strain of the reinforcement is measured with fiber optic sensors. Approached by the methods of moment-curvature relations, the steel strains serve as a reference for velocity changes of the coda waves. In particular, a correlation between the relative velocity change and the average steel strain in the reinforcement is derived that covers 90% of the total bearing capacity. The purely empirical model yields a linear function with a high level of accuracy ( Civil engineers have long been aware of the gradual aging of infrastructure. Global availability of raw materials, ease of workability, almost arbitrary formability, and economic considerations have led to the vast majority of existing structures being made of reinforced concrete (RC). Its increasingly critical state of preservation has driven their activities. Today, regular inspection on-site, i.e., of bridges, is part of the daily business of structural inspectors. However, annual intervals of visual inspection  do not rDistinction can be made according to the information content ascribed to a sensor (0D/1D/2D/3D), the number of sensors required in a network to detect and track local or global changes, but also regarding the measuring principle optical, acoustic).Acoustic Ultrasonic (US) measurement methods are characterized by the fact that a wide volume can be investigated already with a single transmitter-receiver pair. Traditional transmission and reflection methods mainly analyze the direct wave between the transmitter and receiver by means of the time of flight ,8. Thus,Much effort has been spent on the material level on small compressive strains of concrete in the elastic domain ,12,13,14Basically, RC structures are that successful due to the symbiosis of the two materials, steel and concrete. They are usually subjected to bending, which causes local compressive and tensile zones, and designed in such a way that (tensile) failure is always announced in good time and in a ductile manner. Once concrete cracks in tension, the embedded reinforcement takes all tensile forces (by bond) and enables exploiting RC’s capacity far beyond the elastic range. Macro-cracks (of limited width for durability reasons) are thus an elementary part of the construction method and by no means an exclusive indicator of imminent failure. They are inevitable, and thus, proper monitoring must cope them and only alert authorities when critical limits are reached.The load-bearing behavior of RC after the first crack is crucial. However, previous research could only establish correlations for the non-cracked state. This article is dedicated to the  entire load-bearing behavior of RC, including the cracked state.Attempts to establish a direct correlation between strain and coda characteristics experimentally beyond the elastic range have failed so far . EmployeThis similarity shall be used here specifically to establish integral correlation on structural level. Abandoning everywhere highly resolved local strains, this is done in reflection of an integral but representative velocity change of a scanned partial volume between sensor pairs analogous to the specification of an average steel strain. For this purpose, an RC beam subjected to 4-point bending has been tested at Ruhr University Bochum. In addition to US measurements, the strain in the reinforcement is measured with FOS. The results of this experiment are presented here. Focus is laid on the investigation of the load-bearing behavior of RC members. An approach is presented that allows evaluating the almost entire load-bearing behavior of RC members .The article first introduces the methodology used for US measurements and discusses the key parameter computed thereof. This is followed by a mathematical description of the load-bearing behavior of RC components, and the experiments carried out. Based on these fundamentals, the load-bearing behavior is first analyzed phenomenologically  using various transmitter-receiver combinations. From the similarity to the material behavior of RC, a correlation relationship is developed that enables infering the member condition via US measurements.L, the US wavelength d and the intrinsic absorption length f and velocity v dependent quantity defined by 1low frequency range and stationary wave regime, where the wavelength is greater than the specimen itself. This regime is typically limited to The 2single scattering regime where the wavelength is longer than the grains but smaller than the macroscopic size of the structure  portfolio in civil engineering. Today, methods such as the impact echo ,34, US td Larose  distinguClassical transmission-based US NDT techniques analyze ballistic waves—waves that have directly traveled from transmitter (T) to receiver (R) see . These tResearchers in seismology and US have successfully used the coda to detect minute changes in the earth’s crust and scattering media such as concrete e.g., ,40,41). ,41. 40,4Small changes in the coda between two consecutive measurements are analyzed by the cross-correlation of the associated signals. As in other techniques, such as the doublet technique , this meFor analysis, the relative velocity change As mentioned, the US coda is sensitive to small changes in the sensed material , dependent on the internal stresses.The composite RC composed of concrete and steel possesses a complex load-bearing behavior. As far as the top hierarchy is concerned, it can be classified into a non-cracked and a cracked domain ). Wi). Wi6)).As the tensile is considerably lower than the compressive strength, the load-bearing behavior is typically classified using the tensile capacity. The non-cracked state ➀ is characterized by linear elastic behavior. Both concrete and steel are entirely intact and exhibit identical strains on the same level (fiber) in the cross-section see  left. ThHowever, as the load increases, the stresses exceed the tensile strength on a certain level depending on the concrete grade, the concrete cracks. The bending crack starts from the outermost tensile fiber and runs perpendicular to the neutral axis at center.Only cracked, RC develops its full potential. Its complex load-bearing behavior is usually further subdivided into three complementary ranges . At cracks, the concrete stress and hence the strain immediately drops to 0. Then, the stress that has been borne by the concrete before is redistributed to the reinforcing steel by the bond. As a result, the stress (strain) in the reinforcement is maximum at the crack. Thus, reinforcement and concrete do no longer exhibit identical strains at the same depth (fiber). Over the transfer length When the reinforcement has transferred the entire force released by the first crack into the concrete again, the next crack emerges at the then weakest location (Fcr) cf. .In the third range (➂ completed crack pattern), no new cracks form anymore. The crack spacing is final and lies between Crack before failure is the fundamental design principle of RC. Thus, RC structures are always designed on the safe side, assuming the purely cracked state and neglecting any contribution of concrete to the tensile capacity of the member. In the check of equilibrium of internal forces, all stresses in the compressive zone are ascribed to the concrete while tensile stresses are appointed to the reinforcement. However, what is safe and simple in the design is too extensively idealized regarding realistic deflection prognoses on service level. Taking that simplified assumption, the actual deflection would be strongly overestimated.Thus, in service conditions, it is of utmost importance to carefully take into account the concrete’s contribution to the tensile capacity. That capacity of concrete between the cracks, which increases the total stiffness of the member, is often referred to as tension stiffening. Two alternatives are established to take it into account. One distinguishes a concrete-based formulation ,30 from Mathematically, the—due to cracking—fluctuating steel strain along the beam Equation  by integPlease recall that the calculation of strains in the non-cracked state ➀ is elementary. Without cracks, the strain along the beam For convenience, the following range of cracking ➁ is first skipped. First, focus is set on the range of completed cracking ➂. When cracked, the force between concrete and steel is transferred by bond. Bond is mathematically captured by a bonding law that generally idealizes the location and slip-dependent shear force transfer between concrete and rebar. It describes how the steel strain in the vicinity of a crack develops. The average steel strain in range ➂ follows from Equation .(4)➂:εsHerein, lsewhere ,48,51. TThus, in view of Equation  and FiguEquation .(5)➁:εsy), the ultimate load-bearing capacity of the beam associated with When yielding has occurred  is available . HoweverThus, measurement techniques that provide higher information density (1D to 3D strain data) seem to be essential. With DIC, exclusively two-dimensional surface strains are observable, which is good for concrete strains but makes the acquisition of steel strains of embedded reinforcement infeasible. Furthermore, strain measurement with FOS is a trade-off. One-dimensional strains along optical fibers are obtained in (sub)millimeter resolution. When appropriately applied . The fresh concrete was poured into the prepared formwork and compacted with the aid of a vibrating table. After 28 days of curing, the test was carried out. On the test day itself, the accompanying material tests (concrete and reinforcement) gave the material parameters listed in Approx. 0.8 mMoreover, strain measurements with FOS can be performed quasi continuously . In contrast, US measurements require load steps during testing since they measure differences between load stages. On each load level (under constant load), the US measurements are conducted transmitting from one US transducer and receiving at another. Successively all other combinations are worked through before the load is increased to the next level.As discussed above, the time of cracking  is computed employing Equations –6). Thr. Thr6). In the measuring field between the loads, the strain is constant due to the constant bending moment. Here, the average steel strain (green) can be obtained, analog to Equation , from avThis average strain (quations –6), alb, albεsm,F on the specimen is plotted versus the relative velocity change On the left in Due to the constant bending moment between the concentrated loads, all three combinations on each level form a set and theoretically represent identical states. In the non-cracked state, this is more easily recognized, since a homogeneous stress distribution theoretically exists throughout. Certainly, in the cracked state, this expectation seems justified, too, due to the uniformly distributed cracks caused by the load pattern and the integral sensing of the material by the US signal.Consequently, no further distinction must be made between the individual curves on the same level. They all have the same features and show the same characteristics. Deviations of the curves in a set from each other are attributed to inherent scatter, while the differences between the sets are seen significant in view of material response.In general, all curves in the diagram show two almost linear branches and a range of transition in between. In the range from 0 to 50 kN, they have an initial slope which becomes flatter in transition between 50 and 75 kN and then remains approximately constant until the end. The change in slope is most pronounced for the tensile curves and weakest for the compressive ones. The US signal is more affected in the tensile range than in the compressive range, which is attributed to concrete cracking. Regarding their limits, the three ranges agree with the known limits of the material behavior.F-1Cracking strongly affects the US signal and the key quantities computed with CWI, the correlation coefficient 2The relative velocity change is always negative.3F-Characteristic points associated with significant changes in the material response 4F-A fundamental change of the load-bearing behavior happens in the range of cracking ➁ and is also predicted by the 5F-In agreement with the decreasing slope of the Great similarity to the average strain in the reinforcement computed from the FOS readings according to 1The closer a sensor pair is located to the tensile zone, the more the relative velocity change drops.2With load increase, cracks gradually grow towards the compressive zone at top. This is well-reflected by the trend of the central axis’ gradient towards the tensile one. As the cracks approach the centerline transducers, the US signal is affected more like the signal in the tensile zone.3Not even in the non-cracked state with linear elastic material behavior, the central trend is the average of compressive and tensile trends. Thus, the relative velocity change develops non-linear with the load.As expected and illustrated in Confined to purely mechanical considerations, influences from elastic strain and, above all, from cracks are inseparably linked to the signal. The scanned volume cf.  integratMoreover, uncertain onset of cracking, load-dependent crack growth, as well as the variable compressive and tensile zone heights, cause these proportions to vary with time and load. Different sensitivity to tensile and compressive strains in general and with respect to the material state, cracked or non-cracked, is another factor that affects the magnitude of the relative velocity change.c has to be determined on each individual member. In our case c equals Therein, strain is to be inserted in The model is ready to be used to infer from US measuring data and thereof computed relative velocity changes on the average steel strain in the sensed member.Finally, the model’s range of applicability shall be discussed. In the experiment, the load is increased step-wise up to 300 kN at maximum. Up to this load level, relative velocity changes and reinforcement strains are carefully tracked. From the member’s design according to EC 2 , yieldinSince no significant changes in the load-bearing behavior are to be expected from mechanical reasons until the reinforcement yields, the model can even be used beyond the experimentally validated range. With yielding, 90% of the permissible load range would finally be covered by extrapolation. Both go significantly beyond any other correlations of ultrasonic and structural parameters of RC members found so far, which are all limited to the linear elastic range.The proposed model is based on US measurement data from transducer pairs of 30 cm distance throughout. This distance is not particularly long, neither with regard to usual RC members, nor (and even more so) with regard to the monitoring of entire structures. For reasons of costs and installation, the aim is to use fewer, i.e., more distant, sensors. In construction practice, the optimum is often a compromise between costs and density of the sensor network. Therefore, it has finally been investigated whether a tripled/quadrupled transducer distance has an impact on the obtained results or the found model.The issue is addressed in From the recorded US data, the results for the longest transducer distances are then computed analogously. They are shown as solid lines and cover distances of 90 up to 120 cm. All three follow the mean courses and preserve the key characteristics of the initial curves. No clearly deviating trends can be identified. Thus, it is concluded that even with greater transducer distances, a similar model would be obtained. As long as this is not available, the proposed model might be used instead. One must not expect significant deviations in the proposed steel strains.For the first time, a correlation between a key parameter of ultrasound and a structural state variable is established that covers 90% of the complex load-bearing behavior of RC members. It integrates load-dependent stiffness and concrete cracking.For the beam and a sensor distance of 30 cm, a linear model is established with great confidence: Tripled sensor distances do not impair the proposed correlation function much.Whether in compression or tension, The closer a sensor pair is located to the tensile zone, the more Although Conversely, changes in the compressive zone are more difficult to detect because they are easily superimposed by tension.In the context of an ever-increasing need for structural health monitoring of existing RC structures, the paper links essential key parameters computed from the coda of US signals to structural state variables and their evolution with time and load. Based on empirical data obtained on a simply supported RC beam subjected to four-point bending, a linear model is derived that correlates the relative velocity change of the coda Of course, a general, component-independent correlation relationship for arbitrary RC members has not yet been established. Just a possible approach to achieve this goal has been shown. To achieve this, further experiments are certainly needed, which have to cover not only structural quantities or different concrete composition but also environmental conditions and changes of these. The wide range of influences on the US signal has to be considered for real-world application of this approach. With the consideration of environmental conditions and structural influences, the presented approach can be used to infer the loading of the RC structure by US measurements. A statement about its health becomes possible.


The primary objective of this research was to study the transmission of gamma radiation from heavyweight concrete containing barite aggregates. For this purpose, cylindrical and cubic specimens were produced for 10 mix designs. The mix designs containing different percentages of barite aggregates were calculated; five mix designs were also calculated for the compressive strength of 25 MPa, while five of them were designed for the compressive strength of 35 MPa to study the influence of the compressive strength rate on the reduction in gamma radiation transmission. The results indicated that both compressive and tensile strength was decreased by increasing the ratio of barite aggregates. The rate in reduction of compressive strength and especially tensile strength in concrete C35 was less than in concrete C25. The use of barite aggregates increased the attenuation coefficient of concrete. The attenuation coefficient in C35 concrete increased more than that in C25 upon increasing the amount of barite aggregate. By increasing the thickness of concrete with different percentages of barite, the rate of radiation loss in different samples was closer. The difference in the rate of radiation loss at a thickness of 150 mm was not much different from that at a thickness of 100 mm, whereas it was considerably decreased at a thickness of 300 mm. The test results indicated that the reduction in the gamma transmission rate is significantly dependent on the density of concrete. Today, with the progress in nuclear technology, the application of radiation is becoming widespread in some areas, including the agricultural, industrial, and medical fields. Gamma and X-ray radiation occurs as a result of atomic reactions. These kinds of radiation have high penetration capability in material, and they need to be attenuated using a proper method and material due to the harmful effects of nuclear radiation on humans. The design of radioactive radiation shields is one of the significant concerns in nuclear science.Different materials such as lead, graphite, iron, polyethene, and concrete are used to protect against nuclear radiation. Concrete is one of the most appropriate options, and it is commonly used for such purposes. According to the American concrete institute ACI 211 [3 is categorized as heavyweight concrete. It is usually made using coarse aggregates with specific gravities above 3000 kg/m3 [Commonly, concrete with a unit weight above 2600 kg/m00 kg/m3 .Lead or heavy aggregates are usually used to make heavy concrete. Due to the adverse effects of lead on human health, protective shields can be created using barite, hematite, siderite, limonite, ilmenite, or serpentine containing iron ore, which is generally of high density ,6. The aDelnavaz et al.  experime3. Similarly, Daungwilailuk et al. [Other studies presented combinations of barite aggregate with other materials such as titanium-rich slag , sand, ok et al.  presentek et al.  made conMukhtar Oluwaseun Azeez et al.  carried An investigation was conducted by Mustafa Çullu et al.  at GumusAn investigation on heavy concrete with different iron aggregate inclusions revealed that wave velocity measured from heavy concrete decreased with the increase in iron ore . Ameri eAll this knowledge was considered within the current situation in Iran, which is on a research path toward clean nuclear energy and where barite aggregate is available. Therefore, research requirements were put forward on the amount of replacement for sand and gravel and other influences that can provide the broader knowledge needed for future infrastructure building. A final issue is the relationship of density and linear attenuation coefficient for different grades of concrete containing barite aggregate as a replacement for sand and gravel. To this final question must be added other objectives, which are the subject of the present manuscript. In the present study, the effects of specimen thickness, participation percentage of barite aggregates, and concrete strength grade on gamma radiation absorption rate were investigated. To test the gamma transmission rate and determine the mechanical properties of heavy concrete, five different mix designs were obtained by substituting 0%, 25%, 50%, 75%, and 100% normal aggregates with barite aggregates. Two concrete strength grades with the mentioned substitution rates at thicknesses of 100 mm, 150 mm, and 300 mm were produced and tested.Conventional and barite aggregates were used as aggregates in all concrete samples. The conventional aggregate is an aggregate of normal volume and weight used in the production of conventional concrete mixes. To determine the grading of aggregates, a sieve analysis test was performed on specimens from conventional and barite aggregates according to ASTM C637 . The tesIt is evident from the results that both conventional and barite aggregates had continuous grading. The final diagram was within the standard range, which means that the aggregates were well graded. Moreover, the nominal maximum size of coarse aggregates was 20 mm. The water absorption and specific gravity of fine and coarse aggregates are presented in 3 was used in all the concrete mixes [Type I Portland cement with a specific gravity of 3150 kg/mte mixes . The cheThe physical and chemical properties of the utilized water are summarized in 3 of cement was used, while C35 concrete mixtures contained 410 kg/m3 of cement in every mix. For all concrete mixtures, the water/cement ratio was kept constant at 0.5. Notably, mix design calculations were conducted according to the ACI-211-89 standard [A total of 10 mix designs were generated with different combinations of coarse aggregates. Five mixtures were designed for 25 MPa concrete strength, while five other mixtures were designed to achieve 35 MPa concrete strength. In each C25 mix design, 390 kg/mTo study the influence of concrete specific weight on gamma radiation transmission, barite aggregates were used to replace 0%, 25%, 50%, 75%, and 100% of conventional sand and gravel by weight. Moreover, to investigate the influence of concrete thickness on gamma radiation transmission, cubic specimens with dimensions of 10 cm × 10 cm × 10 cm and 15 cm × 15 cm × 15 cm, as well as cylindrical samples with dimensions of 15 cm × 30 cm, were made. Two samples were made from each mix design, and the total number of samples was 60. Mix designs are demonstrated in The construction of concrete samples was performed in a controlled laboratory environment. Concrete constituents were weighed and then mixed in an electronic mixer. After mixing, process test specimens were cast into mentioned molds. A standard tamper was used to vibrate the samples, and each sample was compacted using the tamper method. Demolding of the specimens was done after 24 h, and then the curing process was implemented using a water tank for 28 days. The standard certified laboratory equipment shown in The unit weight and the compressive and tensile strength of hardened concrete are summarized in The number of transmitted rays through specimens with different thicknesses exposed to gamma radiation was measured by a detector device . The source of gamma radiation was cobalt-60 element, and the radioactive activity of the source was 16.8 mCi. Furthermore, the intensity of radiation without shielding was measured at 520 mSv/h. The distance between the radiation source and the detector device was 55 cm. The arrangement of the test setup is presented in To measure the compressive strength of concrete mix designs, cubic specimens were made as mentioned previously, and their compressive strength was tested using a standard hydraulic testing machine. By comparing the final results, it could be concluded that, by increasing the amount of barite aggregate in the mixture, the compressive strength of the produced concrete would decrease.The reason for this might be the weaker properties of barite aggregates in comparison with conventional aggregates. The loss of strength by increasing the participation ratio of heavy aggregates is illustrated in To determine the tensile strength of samples, the splitting tensile strength test (Brazilian tensile test) was performed on cylindrical specimens. As with compressive strength, the values for tensile strength also decreased upon increasing the heavy aggregates. For a better comparison, the diagram of tensile strength and the participation percentage of heavy aggregates are presented in According to the BS EN 12390-3  standardMoreover, after the tensile strength test, all cylindrical specimens split into two equal parts, which is categorized as an ideal failure mode for the Brazilian tensile test and a satisfactory failure mode by international standards. The dominant failure mode for cylindrical samples is shown in N0 denotes the photon intensities without shielding, N denotes photon intensities with shielding, A is the concrete thickness.According to the Lambert law, the attenuation coefficient of the concrete samples can be calculated from Equation (1) ,26.(1)NN0/N) versus A would provide a straight line, and μ can be determined by the slope’s value. A higher linear attenuation coefficient indicates better radiation absorptive ability.Plotting each ln(μ) and is calculated according to Equation (2). According to the definition of HVL, materials with lower HVL should lead to more thin walls [Another significant factor in the design of radiological protection barriers is the half-value layer thickness (HVL). The half-value layer (HVL) is the minimum thickness of a material that reduces the radiation intensity to 50% of the initial radiation intensity. This thickness is inversely proportional to the attenuation coefficient HVL=The rate of radiation loss is defined as follows:The rate of radiation loss for the control sample and the specimens containing different percentages of barite aggregate versus layer thicknesses is presented in Another important conclusion from As mentioned before, in addition to the transmission flux rate, the HVL  is a main factor for designing and determining the thickness of the protective barrier against gamma rays.The interaction between the attenuation and the HVL for C25 and C35 concrete based on heavy aggregate participation percentages is demonstrated in As depicted in As depicted in 3, and Due to the lower hardness and strength of barite aggregates compared to ordinary aggregates, the compressive and tensile strength of concrete had an inverse relationship with the amount of barite aggregate. By increasing the amount of barite aggregate in the mixture, the rate of reduction in compressive strength and especially tensile strength in concrete C35 was less than in concrete C25.Upon 100% replacement of barite aggregates, the compressive strength of C25 concrete and C35 concrete decreased by 27.52% and 20.82%, respectively, while the tensile strength of C25 concrete and C35 concrete decreased by 32.30% and 13.21%, respectively. This result shows that, according to the mixing design of C25 and C35, increasing the consumption of cement in concrete reduces the intensity of the decrease in compressive strength and especially tensile strength of concrete due to the increase in the amount of barite.The rate of radiation loss in heavy concrete samples increased with the increase in barite aggregates. By comparing C25 and C35 specimens, understandably, the rate of radiation loss in C35 concrete samples was higher than in C25 concrete samples for thinner layers. For C35, as the thickness of concrete increased, the difference in the percentage of radiation transmission reduction decreased in concretes with different percentages of barite aggregates. The difference in the rate of radiation loss in concrete samples of 100 mm thickness without and with 100% barite aggregates reached about 9%. For all C25 and C35 concrete samples with a layer thickness of 300 mm, the rate of radiation loss was between 96% and 99%.From the LAC calculations, it is evident that the LAC of heavy concrete mixes increased with the increase in barite aggregates, while the LAC in C35 concretes with the same percentage of barite was larger than in C25 concretes. The amount of LAC increased by 23% and 35%, respectively, in C35 and C25 concretes with 100% barite compared to samples without barite. The maximum LAC against the cobalt-60 source was recorded as 0.0165 for C35 concrete with 100% barite aggregate.The HVL thicknesses in C25 and C35 concretes with different ratios of barite exhibited noteworthy losses with an increase in barite addition. The HVL decreased by 25% and 19% in C35 and C25 concretes with 100% barite compared to samples without barite.For C25 and C35 concretes, regardless of the strength, the amount of LAC depended on the density of concrete. The relationship between LAC and density of heavyweight concrete made with barite was obtained as a linear equation on the basis of the results that can be used for other thicknesses.In this research, protection against gamma radiation was experimentally evaluated, and radiation absorption tests were performed on concrete specimens produced with ordinary aggregates and heavyweight aggregates. For this aim, concrete samples with thicknesses of 100 mm, 150 mm, and 300 mm were constructed in the lab. Participation percentages of heavy aggregates in different mix designs were selected as 0%, 25%, 50%, 75%, and 100%. The following conclusions can be drawn from this study:


Symptom severity scores after completion of antibiotic treatment among all groups were rated as excellent. Twenty-nine percent of the outpatient antibiotic prescriptions were deemed as inappropriate. A pharmacist call-back service is a simple and inexpensive intervention which can effectively identify opportunities for improving appropriate antibiotic use, particularly with respect to adherence. Pharmacists play a key role in tackling antibiotic misuse through counseling and education of patients and healthcare providers. The study aim is to evaluate the appropriateness of antibiotic prescriptions in community pharmacy settings while implementing an interventional call-back service to assess adherence and symptom resolution among patients prescribed an antibiotic. Patients were recruited by community pharmacists who were assigned to either the call-back, structured counseling, or standard care arms. Patients in the call-back group received intensive antibiotic counseling and a phone call from the study pharmacist 3 to 5 days after antibiotic initiation. The counseling arm patients received intensive antibiotic counseling from the study pharmacist while patients in the standard care arm received routine care. Antibiotic adherence rates among the standard care ( Antimicrobial resistance (AMR) is a major global concern that continues to rise at an alarming rate while posing as a significant threat to public health and safety ,2. ResisMisuse of antibiotics is a known culprit of antibiotic resistance . It is eSeveral regulatory bodies globally mandate the implementation of antimicrobial stewardship programs (ASPs) to improve the judicious use of antibiotics in hospital and community settings ,10. AlthAs community pharmacists embark on opportunities to enhance ASPs in the outpatient setting, studies have demonstrated the success of community pharmacists in improving antibiotic use among patients with interventions such as telephone follow-ups and written and oral communication ,14,15. AA total of 80 patients completed the study. Patient demographics are shown in p = 0.053). Twenty (25%) patients reported having antibiotics remaining after the treatment course. The reasons for antibiotic nonadherence included forgetfulness (35%), delayed start (20%), symptom improvement (15%), ineffective therapy (10%), not reported (10%), using when needed (5%), and occurrence of a side effect (5%). All patients who reported using antibiotics on an as-needed basis and discontinuing the antibiotic after symptom improvement were from the standard care group.Antibiotic adherence rates among the standard care (n = 25), structured counseling (n = 29), and call-back (n = 26) groups were 64%, 86.2%, and 88.5%, respectively , while the median severity score after antibiotic treatment was 3 among all groups . The symptom severity scores  before antibiotic initiation were significant for all groups with median scores of 2, 1, and 1 for the standard care, structured counseling, and call-back groups respectively,  minutes.The call-back service was perceived as useful by 84.6% of patients. The majority of patients (80.8%) reported their experience with the call-back service as excellent and 76.9% reported they would utilize the service again. Pharmacists’ responses regarding the call-back service are shown in p = 0.002).When assessing the patient’s perspective on the pharmacist provided antibiotic counseling, all patients reported that the counseling experience was informative . Median The call-back and structured counseling study arms reported higher antibiotic adherence rates when compared to the standard care group. Published studies using telephone follow-up services have reported antibiotic adherence rates of 78–94% . The adhPharmacists are key to providing education to patients. Studies have shown the positive effects of educating patients on appropriate antibiotic use ,20,21. IIn addition to the pharmacist’s role as an educator, community pharmacists are vital in influencing prescribing habits among providers. In this study, 29.1% of antibiotic prescriptions were deemed inappropriate which is similar to a study conducted by Fleming and colleagues that reported 30% of outpatient antibiotic prescriptions were unwarranted . CommuniGlobally, many community pharmacists continue to dispense antibiotics without a prescription and potentially impact the judicious use of antibiotics ,28,29,30The new knowledge gained from this study is that community pharmacists require targeted and continuous education and training in antimicrobial stewardship. Their roles extend beyond patient counseling and should focus on judicious prescribing of antibiotics. As access to clinical data is limited in many community pharmacies worldwide, antibiotic assessment is mainly restricted to subjective evaluation of patient responses rather than microbiological cultures. Nevertheless, strategies such as encouraging prescribers to write the diagnosis on the prescriptions, implementing delayed prescribing, point of care testing, and developing collaborative practice agreements can be viable options to encourage appropriate antibiotic use within community settings ,33. AMR A few aspects should be considered when interpreting the study findings. Although the test of interest was appropriate, the small sample size hinders the testing for assumptions and small differences. Secondly, antibiotic adherence was measured by self-reported pill counts. Patients may perceive being blamed for not fulfilling their prescribed regimen and may report false data either purposefully or accidently . Lastly A multicentered, interventional study was conducted among six community pharmacies in Qatar. Each community pharmacy was randomly assigned to one of three study groups . Two pharmacists from each of the selected pharmacies were invited to participate in the study. Standardized instructions and training were provided to the pharmacists based on their group assignment.Patients presenting a prescription to the community pharmacist for an oral antibiotic and who were available to be reached by phone were eligible for enrollment by the study pharmacist. Patients who presented with topical antibiotic prescriptions and did not speak Arabic or English were excluded from the study.Study pharmacists assigned to the structured counseling group received standardized training from the research team on how to conduct a thorough patient and medication history and how to provide a comprehensive antibiotic counseling session to patients. Role plays and sample patient cases were used to facilitate the 2 h pharmacist training session. Pharmacists were required to counsel each patient enrolled in the structured counseling study arm on the following: medication name, indication, dose, frequency, duration, side effects, precautions, administration, and how to handle missed doses. Pharmacists were also instructed to educate all patients to complete the whole antibiotic therapy course even if their symptoms started to improve. A counseling booklet of all available oral antibiotics found in Qatar was prepared and provided for each study pharmacist to use as a reference while counseling patients. The comprehensive counseling was provided to each patient prior to dispensing the antibiotic. Study pharmacists allocated to the call-back group also received the same standardized comprehensive antibiotic counseling training as the structured counseling group with an additional one-hour training session on how to conduct the call-back service. During this training, pharmacists were coached and provided with interventional approaches on how to manage antibiotic nonadherence, side effects, and ineffective therapy. In addition to providing comprehensive counseling prior to dispensing the antibiotic, study pharmacists were instructed to call patients 3 days after dispensing the antibiotic with a 5 day therapy duration or call patients 5 days after dispensing for an antibiotic with a 7–10 day therapy duration. During the interventional call, pharmacists were required to ask patients about antibiotic adherence, side effects, and symptom relief. Pharmacists were also instructed to counsel patients on side effect management, offer techniques to improve compliance, and to reemphasize the importance of completing the whole course of antibiotic therapy. If symptoms were not improving after initiation of the antibiotic therapy, pharmacists were instructed to refer patients back to their medical provider for further evaluation.Study pharmacists in the standard care group were instructed to provide care as routine for patients who presented to the pharmacy with an antibiotic. Pharmacists in this study arm did not attend any of the training sessions provided for the structured counseling and call-back study groups. Counseling for patients enrolled in this study arm was at the discretion of the pharmacist.All study pharmacists regardless of study group assignment collected patient demographic information, symptoms (to determine indication for antibiotic use when not specified on the prescription), and symptom severity at time of presentation to the pharmacy. Since the residents of Qatar are from various economic, educational, and ethnic backgrounds, a simple 3-point Likert scale  was utilized to assess the severity of their symptoms. All patients enrolled in the study were followed up by the research team within 1–2 days after completion of their antibiotic therapy to assess for antibiotic adherence by asking about the number of remaining tablets, symptom severity score, and the satisfaction with the counseling provided by the study pharmacist. In addition, patients and pharmacists in the call-back group were also asked about their satisfaction with the interventional call-back service. Patients who were unable to be reached after 2 days were considered lost to follow-up and excluded from data analysis.Given the exploratory nature of this study, a convenience sampling method was used to target 25 patients for each study arm. Six community pharmacies were pre-selected to obtain a representative and diverse sample of residents residing throughout Qatar.The Chi-Square test was used to analyze the antibiotic adherence rates among the study groups while the Kruskal–Wallis test was used to compare the symptom severity score and pharmacist provided counseling among the three study groups. Descriptive statistics were utilized to analyze the demographics, interventions by the call-back group, and satisfaction among patients and pharmacists. The appropriateness of the prescribed antibiotic was evaluated by an expert with infectious disease experience. Prescriptions were deemed appropriate based on the Sanford Guide to Antimicrobial Therapy 2020 , antimicThis study was reviewed and approved by Qatar University Institutional Review Board [QU-IRB 928-E18]. All study participants provided written consent prior to study enrollment. An antibiotic call-back service was favorable among patients and pharmacists. Higher trends of antibiotic adherence were observed among the structured counseling and call-back study groups whereby highlighting the value of the pharmacist provided education. The call-back service may be used as a simple and inexpensive intervention to effectively identify opportunities for improving antibiotic use, particularly with respect to adherence within outpatient settings. Community pharmacists need to be involved in continuous education and training while working collaboratively with general practitioners to improve the judicious use of antibiotics.


Inappropriate use of antibiotics not only increases antibiotic resistance as collateral damage but also increases clinical failure rates and medical costs. The purpose of this study was to determine the relationship between the appropriateness of antibiotic prescription and outcomes of community-acquired acute pyelonephritis (CA-APN).A multicenter prospective cohort study was conducted at eight hospitals in Korea between September 2017 and August 2018. All hospitalized patients aged ≥ 19 years who were diagnosed with CA-APN on admission were recruited. The appropriateness of empirical and definitive antibiotics, as well as the appropriateness of antibiotic treatment duration and route of administration, was evaluated in accordance with the guideline and expert opinions. Clinical outcomes and medical costs were compared between patients who were administered antibiotics ‘appropriately’ and ‘inappropriately.’P = 0.001) and lower medical costs  than those who were administered them ‘inappropriately.’ Similar findings were observed for patients administered both empirical and definitive antibiotics ‘appropriately’ and those administered either empirical or definitive antibiotics ‘inappropriately’.A total of 397 and 318 patients were eligible for the analysis of the appropriateness of empirical and definitive antibiotics, respectively. Of them, 10 (2.5%) and 18 (5.7%) were administered ‘inappropriately’ empirical and definitive antibiotics, respectively. Of the 119 patients whose use of both empirical and definitive antibiotics was classified as ‘optimal,’ 57 (47.9%) received antibiotics over a longer duration than that recommended; 67 (56.3%) did not change to oral antibiotics on day 7 of hospitalization, even after stabilization of the clinical symptoms. Patients who were administered empirical antibiotics ‘appropriately’ had shorter hospitalization days (8 vs. 10 days, Appropriate use of antibiotics leads to better outcomes, including reduced hospitalization duration and medical costs.The online version contains supplementary material available at 10.1186/s12879-022-07097-9. Inappropriate use of antibiotics not only increases antibiotic resistance as collateral damage but also increases clinical failure rates and medical costs . Once a Escherichia coli is the most common causative organism  per high power field); and (v) leukocytosis  , 15. CA-We collected clinical data on demographic features (age and sex), clinical features, clinical outcomes, and medical costs. To assess outcomes, we recorded the length of hospital stay and clinical failure rate. Clinical failure was defined as death or recurrence of APN within 14 days of completing therapy. For the analysis of medical costs, the costs incurred during hospitalization were extracted from the hospital’s financial database. It consisted of costs such as consultation fees, hospitalization expenditures, meals, cost per medication, procedure or operation charges, laboratory examination charges, and radiologic examination charges. Non-reimbursed medical costs were excluded. All costs are presented in USD (1 USD = 1100 KRW).5 CFU/mL were isolated from urine cultures and/or when urinary pathogens were isolated from blood cultures. Identification of bacterial species and their susceptibility to antibiotics were determined using a semi-automated system  in each hospital. The breakpoints of each compound were defined with reference to the Clinical and Laboratory Standards Institute [We analyzed results of the urine and blood culture tests performed at the time of admission. The presence of etiologic agents was confirmed when microorganisms at a concentration of ≥ 10nstitute , and theThe appropriateness of the use of empirical and definitive antibiotics was classified as ‘optimal,’ ‘suboptimal,’ and ‘inappropriate’; ‘optimal’ was regarded as ‘appropriate’ antibiotics use, whereas ‘suboptimal’ and ‘inappropriate’ were regarded as ‘inappropriate’ antibiotic use.The standard for the classification of empirical antibiotics was defined based on the ‘Clinical Practice Guideline for the Antibiotic Treatment of Community-Acquired Urinary Tract Infections’ which is the national clinical practice guideline in Korea . ‘For thPseudomonas aeruginosa—not susceptible to all antibiotics—as the causative pathogen, were excluded. We compared the antibiotics used on the 5th day after urine and/or blood cultures were prepared with the results of the antimicrobial susceptibility test. The ranks of the spectrum of β-lactam and anti-staphylococcal antibiotics are shown in Table The standard for the classification of definitive antibiotics was defined according to the results of the in vitro susceptibility test for causative organisms. Cases without the result of the causative organism or those with multidrug-resistant ‘Optimal’ definitive antibiotic use was considered when the causative organisms were susceptible to the antibiotic used on the 5th day. As for the β-lactam and anti-staphylococcal antibiotics, we considered them as ‘optimal’ definitive antibiotics when the causative organism was not ‘susceptible’ to narrower-spectrum antibiotics and ‘suboptimal’ when the causative organism was ‘susceptible’ to narrower-spectrum antibiotics. If the causative organism was not susceptible to the antibiotic that was used on the 5th day, we defined it as an ‘inappropriate’ definitive antibiotic.Combining the appropriateness of the empirical and definitive antibiotic use, ‘optimal’ antibiotic use was considered when both empirical and definitive antibiotic use was ‘optimal;’ ‘inappropriate’ was considered when at least one of the empirical or definitive antibiotics was ‘inappropriate;’ and ‘suboptimal’ included the remaining cases.To evaluate the appropriateness of the route of administration, we reviewed the clinical status of patients with a causative organism susceptible to antibiotics capable of oral route administration such as fluoroquinolone, third generation cephalosporin, and trimethoprim/sulfamethoxazole. The criteria for eligibility to use oral antibiotics were as follows: (i) normal WBC count  and (ii) normal body temperature (36.1‒37.2 °C) on day 7 of hospitalization . ‘AppropRegarding the duration of antibiotic use, ‘prolonged’ antibiotic duration was defined as > 14 days for simple APN cases; > 14 days from the procedure for complicated APN cases; and > 28 days for renal abscess, cyst infection, and emphysematous pyelonephritis cases .P-value < 0.05.Clinical outcomes and medical costs were compared between patients who were administered antibiotics ‘appropriately’ and ‘inappropriately.’ All statistical analyses were conducted using SPSS version 21 for Windows . Categorical variables were analyzed using Fisher’s exact test, and continuous variables were analyzed using the Mann–Whitney test. We also performed a propensity-score matching analysis with a matching weight of 1:1 or 1:2 to reduce the effects of confounding factors. Age, sex, Charlson comorbidity index, and Pitt bacteremia score were included in the model, and non-matched cases were discarded for the subanalysis. Statistical significance was set at a two-tailed A total of 419 patients with CA-APN were enrolled during the study period. Among them, 22 were excluded for the following reasons: 3 were pregnant, 6 were hospitalized for ≥ 21 days owing to medical problems not associated with APN treatment, and 13 were those whose entire treatment progress was not observed. Finally, 397 patients were included in the analysis.E. coli was the most common causative organism (88.8%), followed by Klebsiella spp. (4.3%) and Enterobacter spp. (1.2%). As for antimicrobial therapy, third or fourth generation cephalosporins (65.2%) were mostly chosen as the initial antimicrobial regimen, followed by fluoroquinolone (18.6%), beta-lactam/beta-lactamase inhibitor (9.1%), and carbapenem (5.3%). Of the 318 patients for whom the antimicrobial susceptibility result of the causative organism was available, 23.6% received initial empirical antibiotics that were discordant to the antimicrobial susceptibility of the causative pathogens. The median duration of antibiotic therapy was 9 days, and 10.6% received surgical procedures including nephrostomy as treatment for APN.Table A total of 397 and 318 patients were eligible for the analysis of the appropriateness of empirical and definitive antibiotics, respectively. Of them, 14 (3.5%) and 69 (21.7%) were classified as patients who were administered ‘inappropriately’ empirical and definitive antibiotics, respectively; 81 (25.5%) were administered either empirical or definitive antibiotics inappropriately.P = 0.001), and lower medical costs  than those who were administered them ‘inappropriately.’ Similarly, Patients administered both empirical and definitive antibiotics ‘appropriately’ had lower medical costs  than those administered either empirical or definitive antibiotics ‘inappropriately’  and lower medical costs  than the ‘inappropriate’ group. As for the appropriateness of duration of antibiotic therapy, a total of 397 patients were eligible for the analysis, and 188 (47.4%) were considered as patients who were administered antibiotics for an ‘inappropriate’ duration. After propensity-score matching, the ‘appropriate’ group showed significantly shorter hospitalization days  and lower medical costs  than the ‘inappropriate’ group  were classified as patients who switched from intravenous antibiotics to oral antibiotics ‘inappropriately’. After propensity-score matching, the ‘appropriate’ group showed significantly shorter hospitalization days  and receiving fluoroquinolone as empirical therapy [Several studies have been conducted on the appropriateness of antibiotic prescriptions in patients with UTIs, and the rate of inappropriate antibiotic prescription varies according to the study settings and types of antibiotics evaluated. Regarding the type of empirical antibiotics, a study in the Netherlands found that approximately 30% of empirical antibiotic prescriptions for complicated UTIs did not follow national guidelines . Anotherortality . Accordiortality . Similar therapy . A possi therapy .Interestingly, even though the type of antibiotics was ‘optimal,’ approximately half of the UTI patients were administered antibiotics for a prolonged duration. Similar findings have been reported in other countries. In the US, > 75% of patients with uncomplicated UTIs did not adhere to the recommended antibiotic duration . A retroIn addition to the inappropriate antibiotic duration, not changing to oral antibiotics even after stabilization of the clinical symptoms is another problem. Not only did patient factors such as initial poor condition or delayed response to antibiotics but also clinician factors such as misconception or unawareness of the guidelines delayed the oral switch . BecauseThere are some potential limitations of our study. First, the standards of ‘inappropriate’ antibiotic use in the present study were relatively generous. For instance, we considered all antimicrobials mentioned in the Korean guideline as ‘appropriate’ regardless of patients’ medical history or clinical status; antimicrobials to which the causative pathogen showed susceptibility, regardless of the antimicrobial spectrum, were considered as ‘appropriate.’ This might be associated with the fact that the current study showed only a small proportion of patients who were administered antibiotics inappropriately. In fact, defining the rank of the spectrum of each antibiotic is a controversial matter and is difficult to classify strictly . In addiAppropriate use of antibiotics leads to better outcomes, including reduced hospitalization duration and medical costs. ASP should be emphasized to promote appropriate antibiotic prescription in the treatment of UTI.Additional file 1: Table S1. Clinical outcomes and medical costs of community-acquired acute pyelonephritis according to the appropriateness of antibiotic use: before propensity-score matching.


IgG4-related cholecystitis, which is a manifestation of IgG4-related disease in the gallbladder, is associated with autoimmune pancreatitis or IgG4-related sclerosing cholangitis in most cases; isolated gallbladder lesions without systemic manifestations are very rare. Gallbladder wall thickening is often diffuse, but sometimes localized, in which case, differentiation from gallbladder cancer becomes difficult. The characteristic features of IgG4-related cholecystitis on imaging that would enable differentiation from gallbladder cancer remain poorly described.We present a rare case of isolated IgG4-related cholecystitis with localized gallbladder wall thickening that was clinically difficult to distinguish from malignancy before resection. An 82-year-old man was referred to our hospital because of gallbladder wall thickening on abdominal ultrasonography without any symptoms. Dynamic computed tomography of the abdomen showed localized wall thickening from the body to the fundus of the gallbladder that was enhanced from an early stage with a prolonged contrast effect. There were no other findings, such as pancreatic enlargement and bile duct dilatation. Magnetic resonance cholangiopancreatography revealed neither dilatation nor stenosis of the bile duct and pancreatic duct. Endoscopic ultrasonography (EUS) showed a smooth layered thickening of the gallbladder wall with a maximum thickness of 6 mm and a well-preserved outermost hyperechoic layer in the same area. Laparoscopic cholecystectomy was performed because malignancy could not be completely ruled out. Pathological examination of a resected specimen revealed IgG4-positive plasma cell infiltration, fibrosis, and phlebitis. Although the serum IgG4 level measured after resection was normal, the condition was ultimately diagnosed as probable IgG4-related cholecystitis according to the 2020 revised comprehensive diagnostic criteria for IgG4-related disease. The EUS images reflected the pathological findings, in which lymphocytic infiltration was distributed in a laminar fashion in the gallbladder wall.Although rare, isolated IgG4-related cholecystitis with localized wall thickening mimicking gallbladder cancer remains a clinical problem. A smooth laminar thickening of the gallbladder wall on EUS imaging could be one of the most informative characteristics for differentiating IgG4-related cholecystitis from gallbladder cancer. IgG4-related disease is an immune-mediated fibroinflammatory condition characterized by frequent elevation of serum IgG4 levels, multiple organ involvement with abundant lymphocytic infiltration containing an accumulation of IgG4-positive plasma cells, and fibrosis . In geneIn this article, we report a rare case of isolated IgG4-related cholecystitis with an interesting appearance on endoscopic ultrasonography (EUS), along with a review of the literature.An 82-year-old man presented to the local clinic with abnormal liver function, and gallbladder wall thickening was found on abdominal ultrasonography (US). He was referred to our hospital for further examination. At the time of the initial visit, a physical exam revealed no abnormalities in vital signs and no abdominal findings. The patient had a 12-year history of hyperlipidemia and had undergone unilateral lobectomy plus isthmectomy for follicular carcinoma of the right thyroid gland in his 70 s. On admission, a complete blood count and serum chemical studies reflected no abnormal findings, no increase in inflammatory response, and tumor markers within normal limits . Dynamic computed tomography (CT) showed localized wall thickening from the body to the fundus of the gallbladder, which was enhanced from an early stage and showed a prolonged contrast effect. There were no other findings, such as pancreatic enlargement, bile duct dilatation, or retroperitoneal fibrosis Fig. . AlthougHerein, we report the rare case of a patient with localized IgG4-related cholecystitis without any other organ involvement, including the pancreas and bile duct. Interestingly, EUS findings of the gallbladder wall thickening revealed a characteristic feature, that is, a smooth layered thickening, which could be useful for differentiating IgG4-related cholecystitis from gallbladder cancer on imaging.IgG4-related cholecystitis is considered a lesion of IgG4-related disease. It usually presents as a gallbladder wall thickening synchronous with autoimmune pancreatitis or IgG4-related sclerosing cholangitis , 11, 12,The pathological features are characterized by a dense lymphoplasmacytic infiltration, IgG4-positive cell infiltration, inflammation often involving all layers, storiform fibrosis, obstructive phlebitis, and normal mucosal epithelium of the gallbladder , 13.A PubMed search for past case reports from January 2005 to August 2021 using the search term "IgG4-related cholecystitis" retrieved 16 cases /CT, and EUS are commonly used to evaluate IgG4-related disease. PET/CT imaging is considered a useful tool for the differential diagnosis of IgG4-related disease from malignant tumors. However, the utility of serial fluorodeoxyglucose-PET studies has not been shown in guiding treatment decisions . There aThe findings of this case report are limited because the EUS findings are of only one case with IgG4-related cholecystitis. In addition, we did not measure the levels of serum IgG4 before surgery. Furthermore, we have been following this patient to determine whether ectopic relapse occurred in other organs after surgery for only 1.5 years. We must accumulate more cases with IgG4-related cholecystitis to elucidate the clinical characteristics and typical features on imaging, especially EUS, of IgG4-related cholecystitis and to establish a differential diagnosis from gallbladder cancer.In this study, we experienced a rare case of localized IgG4-related cholecystitis without other organ involvement, such as autoimmune pancreatitis or IgG4-related sclerosing cholangitis. The finding of smooth, laminar wall thickening of the gallbladder wall by EUS may be a key point differentiating this disease from gallbladder carcinoma.


The main objective of electrical-property tomography (EPT) is to retrieve dielectric tissue parameters from  The conductivity and permittivity values of different tissue types are of great importance in a variety of medical applications. In magnetic-resonance (MR) safety  and hypef = γB0, where γTypically, tissue conductivity and permittivity values are measured ex vivo for a particular range of frequencies . Other mReconstruction of dielectric tissue parameters is based on the measured problems , and sevferences ,10,11,12ferences ,16,17,18ferences ,20.In this paper, we focus on a global integral-based EPT reconstruction method called contrast source inversion (CSI)–EPT, where a CSI approach ,22,23 isMinimization of the objective function is carried out by iteratively updating a contrast function, which describes the dielectric constitution of the body part of interest, and a so-called contrast source, which is the product of the contrast function and the electric-field strength. Updating takes place by fixing one variable and updating the other. More precisely, the contrast function is first fixed, the contrast source is updated, and subsequently the contrast source is fixed and the contrast function is updated.z-axis) and the magnetic field is purely transverse, because it is significantly less complex than full three-dimensional implementation. The use of a 2D approach was justified since it was shown that the electromagnetic field in the midplane of a birdcage coil essentially has an E-polarized field structure =j1B^sc(x)=jx and y components =jgiven byB^sc(ρ)=jo obtainB^1+;sc=ωEquation , we obsetor, andA^sc(ρ)=∫Equation . DiffereIn two dimensions, the CSI–EPT algorithm can be simplified by exploiting the particular structure of E-polarized RF fields. To make this simplification explicit, we first introduce differentiation operator Equation  in EquatEquation  to obtaiAs shown in Reference , after tEquation . The oveListing 2. First-Order Induced Current EPT Algorithm (foIC-EPT).Determine the induced current density using Equation .Determine the corresponding electric-field strength by solving a specific integral equation , since,Up to this point, we compared 3D RF field structures with their 2D counterparts for a longitudinally uniform and a realistic heterogeneous head model. In a two-dimensional configuration, however, sources are invariant in the longitudinal direction as well, and we expect that, due to the finite extent of the birdcage coil, additional deviations in the To further investigate this issue, we first determine the two-dimensional To illustrate how these differences in actual fields (3D) and expected fields (2D) translate to reconstruction errors, both two-dimensional algorithms were applied to quasi-three-dimensional data using either 3D amplitudes or phases. Note that, in order to match 2D and 3D data, the maximum absolute value of the The reconstructions of the conductivity and relative permittivity profiles for the full 3D case without any further assumptions, using 3D magnitude as well 3D phase Finally, to emphasize that 3D CSI–EPT is a fully three-dimensional volumetric reconstruction method, we present a full 3D CSI–EPT reconstruction of the realistic head model obtained after 50,000 iterations based on 3D We investigated the performance of two- and three-dimensional CSI–EPT in reconstructing dielectric tissue profiles based on problems . In CSI–obtained . In addiobtained , which iWe carried out several comparisons between reconstructions obtained with 2D CSI–EPT, foIC-EPT, and 3D CSI–EPT. Our simulations show that care needs to be exercised when a 2D reconstruction approach is followed or reconstruction artefacts are obtained in the reconstructed dielectric tissue profiles. Specifically, we showed that, by using 2D methods, erroneous reconstructions could be obtained, since the longitudinal variations of the transverse vector potential are completely ignored in the data model for the No assumptions on the fields are imposed in 3D CSI–EPT and reconstruction errors due to such assumptions are therefore avoided. Moreover, 3D CSI–EPT is a volumetric reconstruction method, and is not restricted to a specific plane within the configuration. Reliable reconstructions can be obtained within any desired domain of interest provided that eference , for exaIn our experiments, we used simulated First, in practice, the foIC-EPT  and, as foIC-EPT , total-vSecond, the phase that is measured in practice is not the phase of the profiles . Fortunaprofiles  that impferences ,33.Finally, in practice, the current densities in the transmit coil that generate the incident field depend on the present object, and we must account for this loading effect as well. Specifically, integral representations for the fields in CSI–EPT are obtained using scattered-field formalism in which it is assumed that current density in the transmitting antenna is impressed and independent of the scatterer that may be present in the configuration. In practice, however, these currents do depend on the object, and, consequently, care must be taken when we compute the background field in CSI–EPT. One approach is, therefore, to simulate this loading effect using a suitable coil and body model in a commercial field solver and to extract current densities in the coil from this solver. The background field in CSI–EPT (the field without any load) can then be computed using these extracted currents. In this way, the loading effect encountered in practice can be incorporated in our CSI–EPT reconstruction algorithm.Our final aim is, of course, to turn CSI–EPT into a practical reconstruction method to obtain accurate and reliable conductivity and permittivity tissue maps of an interior part of the human body at MR operation frequencies. Reconstruction results based on simulated data are very promising, and we think that, by addressing the practical issues discussed above, we will indeed make significant progress towards a reliable EPT reconstruction method that provides us with accurate dielectric tissue maps in practice.


The 2019 Infectious Diseases Society of America/American Thoracic Society community-acquired pneumonia (CAP) guidelines eliminated the term healthcare-associated pneumonia (HCAP), and recommends to guide the use of broad-spectrum antibiotics by locally validating the prevalence and risk factors of multi-drug resistant organisms (MDROs). The objective of this study is to determine the prevalence and associated patient characteristics of MDROs, and to characterize antibiotic prescribing patterns.This was a retrospective, cohort study in adult patients hospitalized from 1/1/19 to 12/31/19. Patients were randomly selected from a patient list of diagnosis codes suggestive of pneumonia. We excluded patients with antibiotic therapy < 48 hours, bacterial co-infections from another site, or transferred from another hospital with length of stay >24 hours. Endpoints evaluated include the percentage of MDRO isolated from a respiratory or blood culture collected within 2 days of admission, comparison of patient characteristics associated with MDROs with those who did not, treatment regimen and duration, and rate of overtreatment and undertreatment. Staphylococcus aureus (MRSA), and Pseudomonas aeruginosa (PSA) was 8%, 3%, and 5%, respectively. Patient characteristics associated with MDROs from are shown in Table 1. Prior MDRO history or recent intravenous (IV) antibiotic exposure during hospitalization was present in 39% of the MDRO cohort. Over half (58%) of the patients were initiated on antibiotics with MRSA and/or PSA coverage. Rate of overtreatment and undertreatment was 89% and 5%, respectively. Mean antibiotic duration was 9 ± 3 days. A total of 220 patients were included. Prevalence of overall MDRO, methicillin-resistant The low prevalence of MDROs, coupled with the high overtreatment and low undertreatment rate suggests most patients hospitalized with CAP at our institution can receive an antibiotic regimen targeting standard CAP pathogens. Antibiotic stewardship intervention to shorten the duration of therapy should be considered. In addition to microbiology history and recent IV antibiotic exposure during hospitalization, further studies are needed to validate other patient characteristics at risk for MDROs.All Authors: No reported disclosures


Many studies have focused on decreasing inappropriate antibiotic prescriptions. In August 2018, our institution implemented an outpatient antibiotic stewardship program (ASP). We describe the impact of an outpatient ASP on the antibiotic choice, dose, and duration for common pediatric infections in a pediatric urgent care (PUC) setting.We reviewed all encounters at 4 freestanding PUC centers within our organization of patients >60 days and < 18 years with a discharge diagnosis of acute otitis media (AOM), group A streptococcal (GAS) pharyngitis, community acquired pneumonia (CAP), urinary tract infection (UTI), cellulitis, abscess, and animal bite who received systemic antibiotics between July 2017 and December 2020. We excluded patients who were transferred, admitted, or had a concomitant diagnosis that required systemic antibiotics. We used established national guidelines to determine appropriateness of antibiotic choice, dose, and duration for each diagnosis (Table 1). Our outpatient ASP efforts included the development of an antibiotic handbook, data sharing, education, quality improvement projects, and commitment letters. Pearson’s chi-square test was used to compare appropriate prescribing  between pre-implementation (July 2017 – July 2018) and post-implementation (August 2018 -forward). Monthly run charts evaluated improvement over time.We included 35,915 encounters. Appropriate antibiotic agent improved in AOM , UTI , cellulitis  and abscess  following implementation of our ASP . Excluding GAS pharyngitis, all diagnoses had improvement in appropriate duration (p< 0.001) . Appropriate dosing improved for AOM , UTI  animal bites , and cellulitis  .Figure 1. Appropriate AgentRun chart of percentage of encounters with antibiotic choice consistent with national guideline recommendations by discharge diagnosis. The vertical line indicates the start of outpatient antibiotic stewardship efforts in August 2018.Figure 2. Appropriate DurationRun chart of percentage of encounters with antibiotic duration consistent with national guideline recommendations. The vertical line indicates the start of outpatient antibiotic stewardship efforts in August 2018.Figure 3. Appropriate DoseRun chart of percentage of encounters with antibiotic dose consistent with national guideline recommendations. The vertical line indicates the start of outpatient antibiotic stewardship efforts in August 2018.Our outpatient ASP improved prescribing patterns for agent, duration, and dose for many common pediatric infections in the PUC setting. Future work will focus on identifying opportunities to improve prescribing practices when antibiotics are indicated.Brian R. Lee, PhD, MPH , Merck (Grant/Research Support)Pfizer (Grant/Research Support)