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1.
Endosc Int Open ; 11(6): E599-E606, 2023 Jun.
Article En | MEDLINE | ID: mdl-37614641

Background and study aims American Society of Gastrointestinal Endoscopy (ASGE) and European Society of Gastrointestinal Endoscopy (ESGE) guidelines recommend categorizing patients by risk for choledocholithiasis to determine management. The goal of our study was to compare the accuracy of criteria proposed in these guidelines. Patients and methods All patients with suspected choledocholithiasis at our institution were prospectively identified. Based upon initial test results, patients were categorized as low, intermediate, and high risk for choledocholithiasis per ASGE 2010 and 2019, and ESGE criteria. Patients were followed until 30 days post-discharge. Results of endoscopic retrograde cholangiography (ERCP), endoscopic ultrasound, and magnetic resonance cholangiopancreatography were used as criteria standard for choledocholithiasis. The accuracy of each criterion for choledocholithiasis was computed. Results During the study period, 359 consecutive patients with suspected choledocholithiasis were identified, of whom 225 had choledocholithiasis. Median patient age was 69 years and 55.3% were women. ESGE criteria categorized 47.9% as high-risk, lower than ASGE 2010 (62.7%, P <0.01), and 2019 criteria (54.6%, P =0.07). In high-risk patients, choledocholithiasis was noted in 83.1% for ESGE criteria, similar for ASGE 2019 (81.6%, P =0.7) and 2010 criteria (79.1%, P =0.3). The percentage of patients who underwent unnecessary ERCP was 8.1% per ESGE criteria, lower than ASGE 2010 (13.1%, P =0.03), but similar to 2019 criteria (10%, P =0.4). No difference in accuracy for choledocholithiasis was noted among the three criteria. No 30-day readmissions for choledocholithiasis were noted in the low-risk category. Conclusions ESGE and ASGE guidelines have similar accuracy for diagnosis of choledocholithiasis. However, ESGE criteria result in more patients needing additional testing, but also a smaller proportion of patients undergoing unnecessary ERCP.

2.
AJR Am J Roentgenol ; 221(2): 196-205, 2023 08.
Article En | MEDLINE | ID: mdl-36946899

BACKGROUND. Distal pancreatitis is an atypical imaging subtype of acute pancreatitis involving only the pancreatic body and tail, the head being spared. If no cause is identified, suspicion of a small imaging-occult cancer may be warranted. OBJECTIVE. The purpose of this study was to determine the frequency of subsequently diagnosed pancreatic cancer in patients with unexplained acute distal pancreatitis and to compare this frequency to that found in patients with unexplained nondistal pancreatitis. METHODS. This retrospective study included patients who underwent contrast-enhanced CT between January 1, 2019, and December 31, 2020, that showed acute pancreatitis without identifiable explanation. Studies were classified as showing distal or nondistal acute pancreatitis on the basis of consensus. The Fisher exact test was used to compare the frequency of subsequent histologic diagnosis of pancreatic cancer between groups. Negative classification required 6 or more months of imaging follow-up and/or 12 or more months of clinical follow-up. Interreader agreement among seven readers of varying experience was assessed by Fleiss kappa. RESULTS. Among 215 patients with acute pancreatitis, 116 (54%) had no identifiable explanation and formed the study sample. A total of 100 of 116 (86%) patients (59 men, 41 women; mean age, 57 ± 18 [SD] years) had nondistal acute pancreatitis; 16 of 116 (14%) patients (10 men, six women; mean age, 66 ± 14 years) had distal acute pancreatitis. Among patients with nondistal pancreatitis, none were subsequently diagnosed with pancreatic cancer; 62 had sufficient follow-up (median, 2.5 years) to be classified as having negative follow-up for pancreatic cancer. Among patients with distal pancreatitis, nine were subsequently diagnosed with pancreatic cancer (median interval to suspected cancer on subsequent CT, 174 days); five had sufficient follow-up (median, 3.1 years) to be classified as having negative follow-up for pancreatic cancer. The frequency of pancreatic cancer was higher (p < .001) in patients with distal pancreatitis (9/14 [64%; 95% CI, 35-87%]) than in with those with nondistal pancreatitis (0/62 [0%; 95% CI, 0-6%]). Interreader agreement on classification of distal versus nondistal pancreatitis was almost perfect (κ = 0.81). CONCLUSION. Distal pancreatitis without identifiable cause on CT is an uncommon but unique imaging subtype of acute pancreatitis that is associated with a high frequency of pancreatic cancer. CLINICAL IMPACT. In patients with acute distal pancreatitis without identifiable cause, endoscopic ultrasound-guided biopsy should be considered to evaluate for an underlying small cancer.


Pancreatic Neoplasms , Pancreatitis , Male , Humans , Female , Adult , Middle Aged , Aged , Aged, 80 and over , Pancreatitis/diagnostic imaging , Pancreatitis/complications , Retrospective Studies , Acute Disease , Pancreas/pathology , Pancreatic Neoplasms/complications , Pancreatic Neoplasms/diagnostic imaging , Pancreatic Neoplasms
3.
Abdom Radiol (NY) ; 48(1): 318-339, 2023 01.
Article En | MEDLINE | ID: mdl-36241752

PURPOSE: Surgical resection is the only potential curative treatment for patients with pancreatic ductal adenocarcinoma (PDAC), but unfortunately most patients recur within 5 years of surgery. This article aims to assess the practice patterns across major academic institutions and develop consensus recommendations for postoperative imaging and interpretation in patients with PDAC. METHODS: The consensus recommendations for postoperative imaging surveillance following PDAC resection were developed using the Delphi method. Members of the Society of Abdominal Radiology (SAR) PDAC Disease Focused Panel (DFP) underwent three rounds of surveys followed by live webinar group discussions to develop consensus recommendations. RESULTS: Significant variations currently exist in the postoperative surveillance of PDAC, even among academic institutions. Differentiating common postoperative inflammatory and fibrotic changes from tumor recurrence remains a diagnostic challenge, and there is no reliable size threshold or growth rate of imaging findings that can provide differentiation. A new liver lesion or peritoneal nodule should be considered suspicious for tumor recurrence, and the imaging features should be interpreted in the appropriate clinical context (e.g., CA 19-9, clinical presentation, pathologic staging). CONCLUSION: Postoperative imaging following PDAC resection is challenging to interpret due to the presence of confounding postoperative inflammatory changes. A standardized reporting template for locoregional findings and report impression may improve communication of relaying risk of recurrence with referring providers, which merits validation in future studies.


Carcinoma, Pancreatic Ductal , Gastrointestinal Diseases , Pancreatic Neoplasms , Radiology , Humans , Neoplasm Recurrence, Local/diagnostic imaging , Neoplasm Recurrence, Local/pathology , Pancreatic Neoplasms/diagnostic imaging , Pancreatic Neoplasms/surgery , Carcinoma, Pancreatic Ductal/diagnostic imaging , Carcinoma, Pancreatic Ductal/surgery , Carcinoma, Pancreatic Ductal/pathology , Tomography, X-Ray Computed , Pancreatic Neoplasms
4.
J Thorac Cardiovasc Surg ; 165(2): 518-525, 2023 02.
Article En | MEDLINE | ID: mdl-35764462

OBJECTIVES: This study examines the long-term anatomic and clinical effects of tracheobronchoplasty in severe excessive central airway collapse. METHODS: Included patients underwent tracheobronchoplasty for excessive central airway collapse (2002-2016). The cross-sectional area of main airways on dynamic airway computed tomography was measured before and after tracheobronchoplasty. Expiratory collapse was calculated as the difference between inspiratory and expiratory cross-sectional area divided by inspiratory cross-sectional area ×100. The primary outcome was improvement in the percentage of expiratory collapse in years 1, 2, and 5 post-tracheobronchoplasty. Secondary outcomes included mean response profile for the 6-minute walk test, Cough-Specific Quality of Life Questionnaire, Karnofsky Performance Status score, and St George Respiratory Questionnaire. Repeated-measures analysis of variance was used for statistical analyses. RESULTS: The cohort included 61 patients with complete radiological follow-up at years 1, 2, and 5 post-tracheobronchoplasty. A significant linear decrease in the percentage of expiratory collapsibility of the central airways after tracheobronchoplasty was present. Anatomic repair durability was preserved 5 years after tracheobronchoplasty, with decrease in percentage of expiratory airway collapse up to 40% and 30% at years 1 and 2, respectively. The St George Respiratory Questionnaire (74.7 vs 41.8%, P < .001) and Cough-Specific Quality of Life Questionnaire (78 vs 47, P < .001) demonstrated significant improvement at year 5 compared with baseline. Similar results were observed in the 6-minute walk test (1079 vs 1268 ft, P < .001) and Karnofsky score (57 vs 82, P < .001). CONCLUSIONS: Tracheobronchoplasty has durable effects on airway anatomy, functional status, and quality of life in carefully selected patients with severe excessive central airway collapse.


Cough , Thoracic Surgical Procedures , Humans , Quality of Life , Exhalation/physiology
5.
Int J Mol Sci ; 23(21)2022 Oct 25.
Article En | MEDLINE | ID: mdl-36361660

Unlike the α-helical and ß-sheet antimicrobial peptides (AMPs), our knowledge on amino acid-rich AMPs is limited. This article conducts a systematic study of rich AMPs (>25%) from different life kingdoms based on the Antimicrobial Peptide Database (APD) using the program R. Of 3425 peptides, 724 rich AMPs were identified. Rich AMPs are more common in animals and bacteria than in plants. In different animal classes, a unique set of rich AMPs is deployed. While histidine, proline, and arginine-rich AMPs are abundant in mammals, alanine, glycine, and leucine-rich AMPs are common in amphibians. Ten amino acids (Ala, Cys, Gly, His, Ile, Lys, Leu, Pro, Arg, and Val) are frequently observed in rich AMPs, seven (Asp, Glu, Phe, Ser, Thr, Trp, and Tyr) are occasionally observed, and three (Met, Asn, and Gln) were not yet found. Leucine is much more frequent in forming rich AMPs than either valine or isoleucine. To date, no natural AMPs are simultaneously rich in leucine and lysine, while proline, tryptophan, and cysteine-rich peptides can simultaneously be rich in arginine. These findings can be utilized to guide peptide design. Since multiple candidates are potent against antibiotic-resistant bacteria, rich AMPs stand out as promising future antibiotics.


Amino Acids , Antimicrobial Peptides , Animals , Trypsin , Amino Acid Sequence , Leucine , Peptide Fragments , Peptides , Proline , Arginine , Mammals
6.
Eur Radiol ; 32(5): 3369-3376, 2022 May.
Article En | MEDLINE | ID: mdl-35013764

PURPOSE: To assess the long-term malignancy risk of incidental small pancreatic cysts. MATERIALS AND METHODS: In this HIPAA-compliant, IRB-approved, retrospective, multi-institutional study, the long-term incidence of pancreatic cancer was compared between patients with and without small pancreatic cysts. Patients with incidental pancreatic cysts ≥ 0.5 and < 2.0 cm in maximal diameter, detected on MRI performed between 1999 and 2011, represented the "small pancreatic cyst" group. Patients that underwent MRI between 2005 and 2011 and had no reported pancreatic cysts represented the comparison "no cyst" group. RESULTS: The "small pancreatic cyst" group included 267 patients, ages 63.4 ± 11.8 years, 166/267 (62%) women with a mean follow-up of 8.6 ± 4.3 years, median 9.2 years; the "no cyst" group included 1,459 patients, ages 64.6 ± 12 years, 794/1,459 (54%) women with a mean follow-up of 7.0 ± 4.2 years, median 7.8 (p values 0.12, 0.02, < 0.001, respectively). Two/267 (0.7%) patients developed pancreatic cancer at a separate location from the known cyst in the "small pancreatic cyst" group, with a cancer rate of 0.9 (95% CI 0.1-3.1) cases per 1,000 patient-years. In the "no cyst" cohort, 18/1,459 (1.2%) patients developed pancreatic cancer, with a cancer rate of 1.8 (95% CI 1.2-3.1) cases per 1,000 patient-years (p = 0.6). The all-cause mortality was similar in both groups: 57/267 (21%) vs. 384/1,459 (26%) (p = 0.09). CONCLUSION: The long-term risk of pancreatic malignancy in asymptomatic patients with incidental pancreatic cysts less than 2 cm is 0.9 cases per 1,000 patient-years of follow-up, similar to those without pancreatic cysts. These very few pancreatic cancers developed at a separate location from the known cyst. KEY POINTS: • After a median of 9.2 years of follow-up, the risk of pancreatic malignancy in patients with an asymptomatic small pancreatic cyst was 0.9 cases per 1,000 patient-years of follow-up, similar to those without pancreatic cysts. • Very few pancreatic cancer cases developed in the location separate from the known pancreatic cyst.


Pancreatic Cyst , Pancreatic Neoplasms , Aged , Female , Follow-Up Studies , Humans , Incidence , Incidental Findings , Male , Middle Aged , Pancreatic Cyst/diagnostic imaging , Pancreatic Cyst/epidemiology , Pancreatic Cyst/pathology , Pancreatic Neoplasms/diagnostic imaging , Pancreatic Neoplasms/epidemiology , Pancreatic Neoplasms/pathology , Retrospective Studies , Pancreatic Neoplasms
7.
J Ginseng Res ; 45(1): 75-85, 2021 Jan.
Article En | MEDLINE | ID: mdl-33437159

BACKGROUND: Invasive infections due to foodborne pathogens, including Salmonella enterica serovar Typhimurium, are prevalent and life-threatening. This study aimed to evaluate the effects of ginsenoside Rg3 (Rg3) on the adhesion, invasion, and intracellular survival of S. Typhimurium. METHODS: The impacts of Rg3 on bacterial growth and host cell viability were determined using the time kill and the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assays, respectively. Gentamicin assay and confocal microscopic examination were undertaken to determine the effects of Rg3 on the adhesive and invasive abilities of S. Typhimurium to Caco-2 and RAW 264.7 cells. Quantitative reverse transcription polymerase chain reaction was performed to assess the expression of genes correlated with the adhesion, invasion, and virulence of S. Typhimurium. RESULTS: Subinhibitory concentrations of Rg3 significantly reduced (p < 0.05) the adhesion, invasion, and intracellular survival of S. Typhimurium. Rg3 considerably reduced (p < 0.05) the bacterial motility as well as the release of nitrite from infected macrophages in a concentration-dependent manner. The expression of genes related to the adhesion, invasion, quorum sensing, and virulence of S. Typhimurium including cheY, hilA, OmpD, PrgK, rsgE, SdiA, and SipB was significantly reduced after Rg3 treatment. Besides, the compound downregulated rac-1 and Cdc-42 that are essential for actin remodeling and membrane ruffling, thereby facilitating Salmonella entry into host cells. This report is the first to describe the effects of Rg3 on "trigger" entry mechanism and intracellular survival S. Typhimurium. CONCLUSION: Rg3 could be considered as a supplement agent to prevent S. Typhimurium infection.

8.
J Biomech Eng ; 143(5)2021 05 01.
Article En | MEDLINE | ID: mdl-33454731

Cough-associated headaches (CAHs) are thought to be distinctive for Chiari malformation type I (CMI) patients and have been shown to be related to the motion of cerebrospinal fluid (CSF) near the foramen magnum (FM). We used computational fluid dynamics (CFD) to compute patient-specific resistance to CSF motion in the spinal canal for CMI patients to determine its accuracy in predicting CAH. Fifty-one symptomatic CMI patients with cerebellar tonsillar position (CTP) ≥ 5 mm were included in this study. The patients were divided into two groups based on their symptoms (CAH and non-CAH) by review of the neurosurgical records. CFD was utilized to simulate CSF motion, and the integrated longitudinal impedance (ILI) was calculated for all patients. A receiver operating characteristic (ROC) curve was evaluated for its accuracy in predicting CAH. The ILI for CMI patients with CAH (776 dyn/cm5, 288-1444 dyn/cm5; median, interquartile range) was significantly larger compared to non-CAH (285 dyn/cm5, 187-450 dyn/cm5; p = 0.001). The ILI was more accurate in predicting CAH in CMI patients than the CTP when the comparison was made using the area under the ROC curve (AUC) (0.77 and 0.70, for ILI and CTP, respectively). ILI ≥ 750 dyn/cm5 had a sensitivity of 50% and a specificity of 95% in predicting CAH. ILI is a parameter that is used to assess CSF blockage in the spinal canal and can predict patients with and without CAH with greater accuracy than CTP.


Arnold-Chiari Malformation
9.
J Neurosurg Sci ; 65(1): 63-68, 2021 Feb.
Article En | MEDLINE | ID: mdl-29480683

BACKGROUND: Most patients with pineal cysts referred for neurosurgical consultation have no specific symptoms or objective findings except for pineal cyst size to help in management decisions. Our purpose was to assess the relationship between pineal cyst size and aqueductal CSF flow using PC-MRI. METHODS: Eleven adult patients with pineal cysts (>1 cm) referred for neurosurgical consultations were included. Cyst volume was calculated using 3D T1 images. Phase contrast magnetic resonance imaging (PC-MRI) in axial plane with velocity encoding of 5 cm/sec was used to quantitatively assess CSF flow through the cerebral aqueduct to determine the aqueductal stroke volume, which was then correlated to cyst size using Pearson's correlation. Pineal cysts were grouped by size into small (6/11) and large (5/11) using the median value to compare aqueductal stroke volume using Mann-Whitney test. RESULTS: Patients were 39±13 years (mean±SD) of age, and 10/11 (91%) were female. There was significant negative correlation between cyst volume and aqueductal stroke volume (r=0.74; P=0.009). Volume of small cysts (4954±2157 mm3) was significantly different compared to large cysts (13,752±3738 mm3; P=0.008). The aqueductal stroke volume of patients harboring large cysts 33±8 µL/cardiac cycle was significantly lower than that of patients with small cysts 96±29 µL/cardiac cycle (P=0.008). CONCLUSIONS: Aqueductal CSF flow appears to decrease with increasing pineal cyst size. Our preliminary results provide first evidence that even in the absence of objective neurological findings or hydrocephalus; larger pineal cysts already display decreased CSF flow through the cerebral aqueduct.


Brain Neoplasms , Cysts , Hydrocephalus , Adult , Cerebral Aqueduct/diagnostic imaging , Child , Cysts/diagnostic imaging , Female , Humans , Hydrocephalus/diagnostic imaging , Magnetic Resonance Imaging
10.
ACS Omega ; 4(3): 5640-5649, 2019 Mar 31.
Article En | MEDLINE | ID: mdl-31459718

In this work, we describe the preparation and characterization of highly magnetizable chloromethylated polystyrene-based nanocomposite beads. For synthesis optimization, acid-resistant core-shelled maghemite (γ-Fe2O3) nanoparticles are coated with sodium oleate and directly incorporated into the organic medium during a suspension polymerization process. A crosslinking agent, ethylene glycol dimethacrylate, is used for copolymerization with 4-vinylbenzyl chloride to increase the resistance of the microbeads against leaching. X-ray diffraction, inductively coupled plasma atomic emission spectroscopy, thermogravimetric analysis, scanning electron microscopy, transmission electron microscopy, and optical microscopy are used for bead characterization. The beads form a magnetic composite consisting of ∼500 nm-sized crosslinked polymeric microspheres, embedding ∼8 nm γ-Fe2O3 nanoparticles. This nanocomposite shows large room temperature magnetization (∼24 emu/g) due to the high content of maghemite (∼45 wt %) and resistance against leaching even in acidic media. Moreover, the presence of superficial chloromethyl groups is probed by Fourier transform infrared and X-ray photoelectron spectroscopy. The nanocomposite beads displaying chloromethyl groups can be used to selectively remove aminated compounds that are adsorbed on the beads, as is shown here for the molecular separation of 4-aminobenzoic acid from a mixture with benzoic acid. The high magnetization of the composite beads makes them suitable for in situ molecular separations in environmental and biological applications.

11.
Neuroimaging Clin N Am ; 29(2): 243-253, 2019 May.
Article En | MEDLINE | ID: mdl-30926114

Headache is a common symptom in patients with Chiari I malformation (CMI), characterized by 5 mm or greater cerebellar tonsillar herniation below foramen magnum. Radiologists should be aware of the different types of headaches reported by CMI patients and which headache patterns are distinctive features of the diagnosis. A methodical imaging strategy is required to fully assess a CMI patient to exclude secondary causes of tonsillar herniation such as intracranial hypotension or associated conditions such as syrinx. Both anatomic and physiologic imaging can help determine if headaches are CMI associated, and assist clinicians in therapeutic decision making.


Arnold-Chiari Malformation/complications , Arnold-Chiari Malformation/diagnostic imaging , Brain/diagnostic imaging , Brain/physiopathology , Headache/etiology , Magnetic Resonance Imaging/methods , Arnold-Chiari Malformation/physiopathology , Humans
12.
J Thorac Imaging ; 34(4): 278-283, 2019 Jul.
Article En | MEDLINE | ID: mdl-29957676

PURPOSE: The purpose of this study was to evaluate intermediate and long-term changes in expiratory tracheal collapsibility by computed tomography (CT) in patients with tracheobronchomalacia following surgical treatment with tracheobronchoplasty and to correlate CT findings with clinical findings. MATERIALS AND METHODS: Between 2003 and 2016, 18 patients with tracheobronchomalacia underwent tracheobronchoplasty and were imaged preoperatively and postoperatively at both intermediate and long-term intervals. Imaging included end-inspiratory and dynamic expiratory phase scans. The cross-sectional area of the airway lumen was measured at 2 standard levels (1 cm above the aortic arch and carina). These measurements were used to calculate % collapsibility. Clinical findings recorded included a questionnaire on symptomatology and a 6-minute walk test. RESULTS: Before surgery, expiratory collapsibility of the upper trachea was 72%±25% (mean±SD) and that of the lower trachea was 68%±22%. On intermediate follow-up (mean, 1.5 y), collapsibility significantly decreased to 37%±21% at the upper trachea and 35%±19% at the lower trachea (P<0.001). On long-term follow-up (mean, 6 y), collapsibility increased to 51%±20% at the upper trachea and 47%±17% at the lower trachea and was significantly worse than on intermediate follow-up (P=0.002). However, collapsibility on long-term follow-up remained significantly lower than preoperative collapsibility (P=0.015). Clinical findings showed a similar trend as quantitative CT measurements. CONCLUSION: Expiratory tracheal collapsibility substantially decreases after tracheobronchoplasty on intermediate follow-up. At long-term follow-up, tracheal collapsibility shows a modest increase, but remains significantly lower than the preoperative baseline. Quantitative measurements from dynamic CT have the potential to play an important role as imaging biomarkers for assessing response to tracheobronchoplasty.


Tomography, X-Ray Computed/methods , Tracheobronchomalacia/diagnostic imaging , Tracheobronchomalacia/surgery , Adult , Aged , Aged, 80 and over , Bronchi/diagnostic imaging , Bronchi/physiopathology , Bronchi/surgery , Female , Follow-Up Studies , Forced Expiratory Volume/physiology , Humans , Longitudinal Studies , Male , Middle Aged , Retrospective Studies , Trachea/diagnostic imaging , Trachea/surgery , Tracheobronchomalacia/physiopathology
13.
Pediatr Radiol ; 47(6): 750-754, 2017 May.
Article En | MEDLINE | ID: mdl-28258425

Image-guided biopsy techniques are widely used in clinical practice. Commonly used methods employ either ultrasound (US) or computed tomography (CT) for image guidance. In certain patients, US or CT guidance may be suboptimal, or even impossible, because of artifacts, suboptimal lesion visualization, or both. We recently began performing magnetic resonance (MR)-guided biopsy of focal liver lesions in select pediatric patients with lesions that are not well visualized by US or CT. This report describes our experience performing MR-guided biopsy of focal liver lesions, with case examples to illustrate innovative techniques and novel aspects of these procedures.


Image-Guided Biopsy/methods , Liver Diseases/diagnostic imaging , Liver Diseases/pathology , Magnetic Resonance Imaging/methods , Adolescent , Child , Child, Preschool , Female , Humans , Infant , Male , Young Adult
14.
Dalton Trans ; 45(16): 6909-19, 2016 Apr 28.
Article En | MEDLINE | ID: mdl-26979820

Mixed actinide(III,IV) oxalates of the general formula M2.2UAn(C2O4)5·nH2O (An = Pu or Am and M = H3O(+) and N2H5(+)) have been quantitatively precipitated by oxalic precipitation in nitric acid medium (yield >99%). Thorough multiscale structural characterization using XRD and XAS measurements confirmed the existence of mixed actinide oxalate solid solutions. The XANES analysis confirmed that the oxidation states of the metallic cations, tetravalent for uranium and trivalent for plutonium and americium, are maintained during the precipitation step. EXAFS measurements show that the local environments around U(+IV), Pu(+III) and Am(+III) are comparable, and the actinides are surrounded by ten oxygen atoms from five bidentate oxalate anions. The mean metal-oxygen distances obtained by XAS measurements are in agreement with those calculated from XRD lattice parameters.

15.
Chem Commun (Camb) ; 52(20): 3947-50, 2016 Mar 11.
Article En | MEDLINE | ID: mdl-26879486

This study demonstrates the ability of ammonium uranyl peroxide nanoclusters U32R-NH4 to undergo exchange in between NH4(+) and trivalent (Nd(3+)) or tetravalent (Th(4+)) cations in the solid state. It paves the way for new promising routes for the synthesis of mixed uranyl peroxides. The exchange ability may also be considered for solution decontamination and synthesis of new mixed actinide-oxide precursors. Both of these applications could be used in the nuclear industry.

16.
Inorg Chem ; 55(1): 51-61, 2016 Jan 04.
Article En | MEDLINE | ID: mdl-26675037

Americium oxalate single crystals, Am2(C2O4)3(H2O)6·4H2O, were prepared by in situ oxalic acid generation by slow hydrolysis of the diester. Their structure was determined by single-crystal X-ray diffraction and was solved by the direct methods and Fourier difference techniques. The structure (space group P21/c, a = 11.184(4) Å, b = 9.489(4) Å, c = 10.234(4) Å, ß = 114.308(8)°, Z = 2) consists of layers formed by six-membered rings of actinide metals connected through oxalate ions. The americium atoms are nine-coordinated by six oxygen atoms from three bidentate oxalate ligands and three water molecules. The distances within the coordination sphere as well as infrared and Raman spectra of several isostructural lanthanide (Ce(III), Pr(III), Nd(III), Sm(III), Gd(III)) and actinide (Pu(III), Am(III)) oxalates were compared to evaluate the similarities and the differences between the two series.

17.
BMC Res Notes ; 8: 400, 2015 Sep 02.
Article En | MEDLINE | ID: mdl-26328612

BACKGROUND: Rabies is a fatal animal disease of significant public health importance. Domestic dogs are the main reservoir and transmitter of this disease particularly in developing countries. Even though rabies is a highly fatal disease, it is a preventable disease. Community awareness about rabies is one of the key components for prevention. This study describes the knowledge, attitudes and practices of a rural community in Gondar Zuria District, Ethiopia. METHODS: A cross sectional study was conducted from March to June, 2013. A structured questionnaire was used to collect the data through face to face interviews among 400 respondents. The data were then analyzed using SPSS statistical software version 20. RESULTS: The current study indicated that almost all (99.3%) of the surveyed individuals were aware of the disease rabies. Rabies is considered to be a fatal disease in humans by 67.8% of the respondents while 27.8% believe that it is a treatable disease. Dogs were indicated as source of infection for humans by all respondents followed by equines (27.2%) and cats (12.1%). Bite was known as mode of rabies transmission by majority of the respondents (94%) while other means were given less weight. Aggression was described as a major clinical sign of rabies in animals. Consumption of cooked or boiled meat from rabid animals was considered as safe by 67.0% of the respondents and about 19% replied even raw meat is safe for human consumption. The need for immediate treatment after exposure was mentioned by less than half (47.4%) of the respondents and only 38.8% of the respondents considered modern medicine as appropriate treatment after exposure to rabid animals. Nearly 42% of respondents had experienced a dog bite. Following the dog bites, only 30.7% practiced washing of the wounds with water as first aid. CONCLUSION: Rabies was found to be well known in the study area. However, knowledge and practices in prevention of rabies were limited. Education of rabies about possible sources of infection, mode of transmission and measures to be taken after exposure is very important in the study area.


Health Knowledge, Attitudes, Practice , Rabies , Rural Population , Animals , Bites and Stings , Ethiopia , Food Microbiology , Humans , Rabies/transmission , Surveys and Questionnaires
18.
Theor Biol Med Model ; 11: 51, 2014 Dec 03.
Article En | MEDLINE | ID: mdl-25471943

BACKGROUND: Papillomavirus binding factor (PBF) or zinc finger protein 395 is a transcription factor associated to a poor prognosis in patients with osteosarcoma, an aggressive bone cancer that predominantly affects adolescents. To investigate the role of the PBF protein in the osteosarcoma genesis, in this paper we present the bioinformatics analysis of physicochemical properties of PBF and its probable interactions with several key cellular targets. RESULTS: The physicochemical characteristics determined to PBF, disorder-promoting amino acids, flexibility, hydrophobicity, prediction of secondary and tertiary structures and probability to be crystallized, supported that this protein can be considered as an intrinsically disordered protein (IDP), with a zinc finger-like domain. The in silico analysis to find out PBF interactions with cellular factors, confirmed the experimentally demonstrated interaction of PBF with two key cellular proteins involved in regulation of cellular apoptosis, 14-3-3ß and Scythe/BAT3 proteins. Furthermore, other interactions were found with proteins like HDAC1 and TPR which are known to be deregulated in several cancers. Experimental confirmation of specific interactions will contribute to understand the osteosarcoma process and might lead to the identification of new targets for diagnosis and treatments. CONCLUSIONS: According to the in silico PBF analyses, this protein can be considered as an IDP capable to bind several key cellular factors, and these interactions might play an important role in the osteosarcoma process.


Bone Neoplasms/virology , Intrinsically Disordered Proteins/metabolism , Osteosarcoma/virology , Papillomaviridae/metabolism , Zinc Fingers , Amino Acid Sequence , Base Sequence , Bone Neoplasms/metabolism , Computer Simulation , Humans , Molecular Sequence Data , Osteosarcoma/metabolism , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid
19.
Nanoscale Res Lett ; 9(1): 499, 2014.
Article En | MEDLINE | ID: mdl-25276103

The effect of Fe ion concentration on the morphological, structural, and optical properties of TiO2 films supported on silica (SiO2) opals has been studied. TiO2:Fe2O3 films were prepared by the sol-gel method in combination with a vertical dip coating procedure; precursor solutions of Ti and Fe were deposited on a monolayer of SiO2 opals previously deposited on a glass substrate by the same procedure. After the dip coating process has been carried out, the samples were thermally treated to obtain the TiO2:Fe2O3/SiO2 composites at the Fe ion concentrations of 1, 3, and 5 wt%. Scanning electron microscopy (SEM) micrographs show the formation of colloidal silica microspheres of about 50 nm diameter autoensembled in a hexagonal close-packed fashion. Although the X-ray diffractograms show no significant effect of Fe ion concentration on the crystal structure of TiO2, the µ-Raman and reflectance spectra do show that the intensity of a phonon vibration mode and the energy bandgap of TiO2 decrease as the Fe(+3) ion concentration increases.

20.
Placenta ; 34(3): 231-9, 2013 Mar.
Article En | MEDLINE | ID: mdl-23347887

INTRODUCTION: Previous studies showed that placental extracts (PE) alleviates arthritic symptoms in animal models of arthritis. METHODS: To evaluate whether murine PEs obtained at embryonic days 7.5 (PE7) and 17.5 (PE18) regulate RANKL-induced osteoclast differentiation, RAW 264.7 cells were cultured with RANKL and MCSF in presence or not of PEs. Tartrate-resistant acid phosphatase (TRAP) was stained and multinucleated TRAP positive cells were visualized under a light microscope. Cathepsin K and metalloprotease expression was assessed by RT-PCR and gelatin zymography respectively. NFATc1 expression was determined by immunoblot. To analyze NFAT-dependent transcription, macrophages were transfected with a luciferase reporter plasmid. Cytokines were determined in PEs by ELISA and immunoblot. Transforming growth factor (TGF)- beta and Interleukin (IL)-10 receptor were inhibited in cell cultures with specific antibodies. RESULTS: PE7 and PE18 inhibited RANKL-induced multinucleated TRAP positive cells, Cathepsin K expression and metalloprotease activity, as well as NFATc1 expression and activity, thereby inhibiting osteoclast differentiation of RAW cells. Inflammatory/Regulatory cytokine ratio was higher in PE7 than in PE18. Blocking TGF-beta abolished the effect of both, PE7 and PE18, on multinucleated TRAP positive cells and metalloprotease expression, whereas blocking IL-10 receptor reverted the effect of PE18 but not of PE7. DISCUSSION: Inhibition of osteoclast differentiation by PEs was not unexpected, since cytokines detected in extracts were previously found to regulate osteoclast differentiation. CONCLUSIONS: PEs inhibited osteoclast differentiation of macrophages in vitro. Downregulation of NFATc1 might be involved in this effect. Regulatory/Th2 cytokines play a role in the effect of PEs on osteoclast differentiation.


Cytokines/pharmacology , Macrophages/cytology , Osteoclasts/cytology , Placenta/metabolism , Acid Phosphatase/metabolism , Animals , Cathepsin K/metabolism , Cell Differentiation/drug effects , Cells, Cultured , Cytokines/analysis , Embryo, Mammalian , Female , Isoenzymes/metabolism , Macrophages/drug effects , Metalloproteases/metabolism , Mice , Mice, Inbred BALB C , NFATC Transcription Factors/metabolism , Osteoclasts/drug effects , Osteoclasts/metabolism , Placenta/chemistry , Pregnancy , RANK Ligand/pharmacology , Tartrate-Resistant Acid Phosphatase , Tissue Extracts/analysis , Tissue Extracts/pharmacology , Transforming Growth Factor beta/antagonists & inhibitors
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