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1.
Clin Infect Dis ; 78(6): e69-e80, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38656065

ABSTRACT

Vascular graft infection (VGI) is one of the most serious complications following arterial reconstructive surgery. VGI has received increasing attention over the past decade, but many questions remain regarding its diagnosis and management. In this review, we describe our approach to VGI through multidisciplinary collaboration and discuss decision making for challenging presentations. This review will concentrate on VGI that impacts both aneurysms and pseudoaneurysms excluding the ascending thoracic aorta.


Subject(s)
Plastic Surgery Procedures , Prosthesis-Related Infections , Humans , Plastic Surgery Procedures/methods , Plastic Surgery Procedures/adverse effects , Prosthesis-Related Infections/surgery , Blood Vessel Prosthesis/adverse effects , Patient Care Team , Aneurysm, False/surgery , Aneurysm, False/etiology , Arteries/surgery
2.
Clin Infect Dis ; 78(6): 1391-1392, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38635420

ABSTRACT

Vascular graft infection (VGI) is one of the most serious complications following arterial reconstructive surgery. VGI has received increasing attention over the past decade, but many questions remain regarding its diagnosis and management. In this review, we describe our approach to VGI through multidisciplinary collaboration and discuss decision-making for challenging presentations. This document will concentrate on VGI that impacts both aneurysms and pseudoaneurysms excluding the ascending thoracic aorta.


Subject(s)
Plastic Surgery Procedures , Prosthesis-Related Infections , Humans , Blood Vessel Prosthesis/adverse effects , Patient Care Team , Plastic Surgery Procedures/methods , Plastic Surgery Procedures/adverse effects , Prosthesis-Related Infections/surgery , Vascular Grafting/adverse effects , Review Literature as Topic
3.
Catheter Cardiovasc Interv ; 103(3): 464-471, 2024 02.
Article in English | MEDLINE | ID: mdl-38287781

ABSTRACT

BACKGROUND: Given the challenges of conventional therapies in managing right-sided infective endocarditis (RSIE), percutaneous mechanical aspiration (PMA) of vegetations has emerged as a novel treatment option. Data on trends, characteristics, and outcomes of PMA, however, have largely been limited to case reports and case series. AIMS: The aim of the current investigation was to provide a descriptive analysis of PMA in the United States and to profile the frequency of PMA with a temporal analysis and the patient cohort. METHODS: The International Classification of Diseases, 10th Revision codes were used to identify patients with RSIE in the national (nationwide) inpatient sample (NIS) database between 2016 and 2020. The clinical characteristics and temporal trends of RSIE hospitalizations in patients who underwent PMA was profiled. RESULTS: An estimated 117,955 RSIE-related hospital admissions in the United States over the 5-year study period were estimated and 1675 of them included PMA. Remarkably, the rate of PMA for RSIE increased 4.7-fold from 2016 (0.56%) to 2020 (2.62%). Patients identified with RSIE who had undergone PMA were young (medial age 36.5 years) and had few comorbid conditions (median Charlson Comorbidity Index, 0.6). Of note, 36.1% of patients had a history of hepatitis C infection, while only 9.9% of patients had a cardiovascular implantable electronic device. Staphylococcus aureus was the predominant (61.8%) pathogen. Concomitant transvenous lead extraction and cardiac valve surgery during the PMA hospitalization were performed in 18.2% and 8.4% of admissions, respectively. The median hospital stay was 19.0 days, with 6.0% in-hospital mortality. CONCLUSIONS: The marked increase in the number of PMA procedures in the United States suggests that this novel treatment option has been embraced as a useful tool in select cases of RSIE. More work is needed to better define indications for the procedure and its efficacy and safety.


Subject(s)
Endocarditis, Bacterial , Endocarditis , Humans , United States/epidemiology , Adult , Inpatients , Suction , Treatment Outcome , Retrospective Studies , Endocarditis/diagnosis , Endocarditis/therapy , Endocarditis, Bacterial/diagnosis , Endocarditis, Bacterial/therapy
4.
J Sport Rehabil ; 32(3): 277-281, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36460005

ABSTRACT

CONTEXT: Collegiate tenpin bowling participation is increasing. Accordingly, the experience level of athletes participating, factors related to performance, as well as training workload and sport specialization are likely evolving. However, literature regarding injury rates remains extremely limited. The purpose of this study was to characterize injuries in collegiate tenpin bowlers. DESIGN: Retrospective cohort survey study. METHODS: Tenpin bowling athletes of top-ranked collegiate programs in the United States were invited to participate. Each participant completed an online survey to report on their injury history and additional factors of interest. Descriptive statistics were generated for participant characteristics, injury counts, and overall injury prevalence and recurrence. Chi-square tests were used to determine if overall injury prevalence and recurrence occurred by chance, and to evaluate the influence of gender and conditioning program participation on injury frequencies. RESULTS: The response rate was 40.6% (101/249; N = 101). The sample was 20.02 (1.43) years old and 54.5% female. There were a total of 235 singular and recurrent injuries reported across all body parts. Upper-extremity injuries were the most common (n = 112). Injury prevalence (87%) and recurrence (75%) were more likely than chance (χ2 > 21.3, both P < .001) and not different based on gender (χ2 ≤ 1.1, both P ≥ .33). Injuries were more frequent in the absence of a conditioning program (χ2 = 50.6, P < .001). CONCLUSIONS: Injuries and injury recurrence in elite tenpin bowlers were frequent, most common in the upper-extremity, not different based on gender, and more frequent in those without conditioning programs. Findings may serve as foundational knowledge for developing sport-specific rehabilitation and conditioning programs.


Subject(s)
Athletic Injuries , Sports , Humans , Female , United States , Infant , Male , Athletic Injuries/epidemiology , Retrospective Studies , Universities , Athletes , Incidence
5.
Circulation ; 143(20): e963-e978, 2021 05 18.
Article in English | MEDLINE | ID: mdl-33853363

ABSTRACT

BACKGROUND: In 2007, the American Heart Association published updated evidence-based guidelines on the recommended use of antibiotic prophylaxis to prevent viridans group streptococcal (VGS) infective endocarditis (IE) in cardiac patients undergoing invasive procedures. The 2007 guidelines significantly scaled back the underlying conditions for which antibiotic prophylaxis was recommended, leaving only 4 categories thought to confer the highest risk of adverse outcome. The purpose of this update is to examine interval evidence of the acceptance and impact of the 2007 recommendations on VGS IE and, if needed, to make revisions based on this evidence. METHODS AND RESULTS: A writing group was formed consisting of experts in prevention and treatment of infective endocarditis including members of the American Dental Association, the Infectious Diseases Society of America, and the American Academy of Pediatrics, in addition to the American Heart Association. MEDLINE database searches were done for English language articles on compliance with the recommendations in the 2007 guidelines and the frequency of and morbidity or mortality from VGS IE after publication of the 2007 guidelines. Overall, there was good general awareness of the 2007 guidelines but variable compliance with recommendations. There was no convincing evidence that VGS IE frequency, morbidity, or mortality has increased since 2007. CONCLUSIONS: On the basis of a review of the available evidence, there are no recommended changes to the 2007 VGS IE prevention guidelines. We continue to recommend VGS IE prophylaxis only for categories of patients at highest risk for adverse outcome while emphasizing the critical role of good oral health and regular access to dental care for all. Randomized controlled studies to determine whether antibiotic prophylaxis is effective against VGS IE are needed to further refine recommendations.


Subject(s)
Endocarditis/prevention & control , Viridans Streptococci/pathogenicity , American Heart Association , Humans , United States
6.
Anal Bioanal Chem ; 414(29-30): 8215-8222, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36258086

ABSTRACT

A new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the analysis of ginsenosides in three Panax ginseng reference materials (RMs). Extraction procedures were optimized to recover neutral and malonyl-ginsenosides using a methanol-water extraction under basic conditions. Optimized mass fragmentation transitions were obtained for the development of a multiple reaction monitoring (MRM) detection method with electrospray ionization in negative and positive ion mode. Mass fraction values were determined for ginsenosides Rb1, Rb2, Rc, Rd, Re, Rf, and Rg1 in the three ginseng materials (rhizomes, extract, and an oral dosage form). Quantitation of these seven compounds was accomplished with 4-methylestradiol and SRM 3389 Ginsenoside Calibration Solution serving as an internal standard (IS) and calibration standards, respectively. Mass fraction values for the seven ginsenosides ranged from 1.27 mg/g to 21.42 mg/g, 3.25 mg/g to 35.81 mg/g, and 0.56 mg/g to 2.51 mg/g for SRM 3384, SRM 3385, and RM 8664, respectively.


Subject(s)
Ginsenosides , Panax , Panax/chemistry , Ginsenosides/analysis , Chromatography, Liquid , Tandem Mass Spectrometry/methods , Rhizome/chemistry , Chromatography, High Pressure Liquid/methods
7.
Attach Hum Dev ; 24(3): 322-338, 2022 06.
Article in English | MEDLINE | ID: mdl-34697999

ABSTRACT

Attachment theory posits that parenting plays akey role in children's attachment and subsequent development. Given the normativity of racial discrimination on everyday life experiences of African American families, there is a need to integrate historical and socio-environmental processes in studies to understand how minoritized parents raise secure and stable children. Results from the current study revealed direct associations between mothers' reports of discrimination and heightened depression and anxiety. Maternal discriminatory experiences were indirectly associated with more negative parenting and compromised parent-child relationship quality, through mothers' psychological functioning. Elevated emotional and behavioral management problems among youth were directly associated with exposure to racial discrimination. Exposure to discrimination during middle childhood facilitated adapted or learned strategies to manage similar situations as youth transitioned into adolescence, with reduced patterns of depressive symptomology. No significant gender effects emerged. Implications for theoretical advancement and future research are provided.


Subject(s)
Parenting , Racism , Adolescent , Black or African American/psychology , Child , Female , Humans , Longitudinal Studies , Mothers/psychology , Object Attachment , Parenting/psychology , Racism/psychology
8.
Clin Infect Dis ; 72(11): 1938-1943, 2021 06 01.
Article in English | MEDLINE | ID: mdl-32533828

ABSTRACT

BACKGROUND: Approximately one-third of cases of cardiovascular implantable electronic device (CIED) infection present as CIED lead infection. The precise transesophageal echocardiographic (TEE) definition and characterization of "vegetation" associated with CIED lead infection remain unclear. METHODS: We identified a sample of 25 consecutive cases of CIED lead infection managed at our institution between January 2010 and December 2017. Cases of CIED lead infection were classified using standardized definitions. Similarly, a sample of 25 noninfected patients who underwent TEE that showed a defined lead echodensity during the study period was included as a control group. TEEs were reviewed by 2 independent echocardiologists who were blinded to all linked patient demographic, clinical, and microbiological information. Reported echocardiographic variables of the infected vs noninfected cases were compared, and the overall diagnostic performance was analyzed. RESULTS: Descriptions of lead echodensities were variable and there were no significant differences in median echodensity diameter or mobility between infected vs noninfected groups. Among infected cases, blinded echocardiogram reports by either reviewer correctly made a prediction of infection in 6 of 25 (24%). Interechocardiologist agreement was 68%. Sensitivity of blinded TEEs ranged from 31.5% to 37.5%. CONCLUSIONS: Infectious vs noninfectious lead echodensities could not be reliably distinguished on the basis of size, mobility, and general shape descriptors obtained from a retrospective blinded TEE examination without knowledge of clinical and microbiological parameters. Therefore, a reanalysis of criteria used to support a diagnosis of CIED lead infection may be warranted.


Subject(s)
Defibrillators, Implantable , Prosthesis-Related Infections , Defibrillators, Implantable/adverse effects , Echocardiography, Transesophageal , Humans , Prosthesis-Related Infections/diagnostic imaging , Reproducibility of Results , Retrospective Studies
9.
Echocardiography ; 37(6): 891-899, 2020 06.
Article in English | MEDLINE | ID: mdl-32416009

ABSTRACT

BACKGROUND: Current guidelines from the American Heart Association (AHA) recommend repeating transesophageal echocardiography (TEE) in three to five days if there is high suspicion of IE despite an initial TEE that was negative. This recommendation, however, is based on limited published data. OBJECTIVES: This investigation attempts to identify specific factors that prompted repeat TEE and evaluate the yield of IE-related findings demonstrated by repeat TEE as compared to initial or prior TEE. METHODS: A retrospective cohort who had at least one repeat TEE during an index hospitalization or initial course of antimicrobial therapy for IE between January 2014 and September 2018. We assessed the impact of repeat TEE on IE diagnosis and patient management and included a comparative analysis of patients with initial TEE only. RESULTS: Overall, 59 (44.7%) of 132 IE patients underwent repeat TEE. In a comparative analysis that involved patients who had undergone an initial TEE only versus those who had repeat TEE, male gender (P = .029) and presence of a prosthetic valve or annuloplasty ring (P = .017) were significantly associated with repeat TEE. Importantly, 8 (17.4%) of repeat TEE were critical for IE diagnosis, 8 (17.4%) impacted antimicrobial management, and 11 (23.9%) supported cardiovascular surgical intervention. CONCLUSIONS: From a population-based cohort of incident IE cases, repeat TEE was more frequently (44.7%) done in patients with suspect or proven IE and associated complications than anticipated. Repeat TEE remains pivotal in a contemporary practice that involves critical aspects of IE diagnosis and management.


Subject(s)
Endocarditis, Bacterial , Endocarditis , Aortic Valve , Echocardiography, Transesophageal , Endocarditis/diagnostic imaging , Humans , Male , Retrospective Studies
10.
Chromatographia ; 83(1)2019.
Article in English | MEDLINE | ID: mdl-33033412

ABSTRACT

We continue herein the exploration of detector orthogonality in size-based macromolecular separations. Previously [5], the sensitivity of viscometric detection was juxtaposed to that of differential refractometry (DRI) and light scattering (LS, both static and dynamic), and it was shown that viscometry is a truly orthogonal detection method to both DRI and LS. Here, via the size-exclusion chromatography (SEC) analysis of blends of polystyrene and poly(methyl methacrylate), we demonstrate the orthogonality of DRI to UV detection and, within the UV region of the electromagnetic spectrum, we also explore the phenomenon of "wavelength orthogonality:" Analytes observable by one detection method are shown to be spectroscopically invisible to another method, or even to the same detection method when operating at a different wavelength. While generally focusing on blends of analytes of different molar masses (different sizes in solution), we also investigate the less-explored case of blends of coeluting analytes (same sizes in solution) where detector orthogonality can inform one's knowledge of whether or not coelution has occurred. Finally, by incorporating a fluorescence (FL) detector into the experimental set-up, we demonstrate not only its orthogonality to DRI detection but also its sensitivity to the presence of even minor (≈ 1%) fluorescent components in a sample. We hope the present experiments assist in understanding the complementarity of different spectroscopic detection methods and also help highlight the potential role of FL detection, a method which has been largely overlooked in macromolecular separation science.

11.
Anal Bioanal Chem ; 410(3): 1123-1137, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29119256

ABSTRACT

Retention indices (I) for 45 polycyclic aromatic hydrocarbons (PAHs) and 63 methyl-substituted PAHs were determined by gas chromatography - mass spectrometry (GC-MS) using two different stationary phases: a Rxi-PAH phase (a "higher phenyl-content stationary phase") and a 50% (mole fraction) liquid crystalline dimethylpolysiloxane phase. Retention data were obtained for parent PAHs from molecular mass (MM) 128 g/mol (naphthalene) to 328 g/mol (benzo[c]picene) and for 12 sets of methyl-PAHs (methylfluorenes, methylanthracenes, methylphenanthrenes, methylfluoranthenes, methylpyrenes, methylbenz[a]anthracenes, methylbenzo[c]phenanthrenes, methylchrysenes, methyltriphenylenes, methylbenzo[a]pyrenes, methylperylenes, and methylpicenes). Molecular shape descriptors such as length-to-breath ratio (L/B) and thickness (T) were determined for all the PAHs studied. Correlation between I and L/B ratio was evaluated for both stationary phases with a better correlation observed for the 50% liquid crystalline phase (correlation coefficients ranging from 0.22 to 1.00). Graphical Abstract GC separation of six methylchrysene isomers (m/z 242) on two different stationary phases: 50 % phenyl-like methylpolysiloxane phase and 50 % liquid crystalline phase. Retention indices (I) are plotted as a function of L/B for both phases. The data marker numbers identify each isomer based on methyl-substitution position.

12.
Anal Bioanal Chem ; 410(5): 1511-1524, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29238863

ABSTRACT

Retention indices for 67 polycyclic aromatic sulfur heterocycles (PASHs) and 80 alkyl-substituted PASHs were determined using normal-phase liquid chromatography (NPLC) on an aminopropyl (NH2) stationary phase. The retention behavior of PASH on the NH2 phase is correlated with the number of aromatic carbon atoms and two structural characteristics have a significant influence on their retention: non-planarity (thickness, T) and the position of the sulfur atom in the bay-region of the structure. Correlations between solute retention on the NH2 phase and T of PASHs were investigated for three cata-condensed (cata-) PASH isomer groups: (a) 13 four-ring molecular mass (MM) 234 Da cata-PASHs, (b) 20 five-ring MM 284 Da cata-PASHs, and (c) 12 six-ring MM 334 Da cata-PASHs. Correlation coefficients ranged from r = -0.49 (MM 234 Da) to r = -0.65 (MM 334 Da), which were significantly lower than structurally similar PAH isomer groups (r = -0.70 to r = -0.99). The NPLC retention behavior of the PASHs are compared to similar results for PAHs.

13.
Anal Bioanal Chem ; 410(3): 885-896, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28660336

ABSTRACT

The relationship of reversed-phase liquid chromatography (RPLC) retention on a polymeric C18 stationary phase and the shape of polycyclic aromatic hydrocarbons (PAHs) was investigated for three-ring to seven-ring cata-condensed isomers. We report the first RPLC separation for six-ring and seven-ring cata-condensed PAH isomers. Correlations of LC retention and shape parameters (length-to-breath ratio, L/B and thickness, T) were investigated for 2 three-ring isomers (molecular mass 178 Da), 5 four-ring isomers (molecular mass 228 Da), 11 five-ring isomers (molecular mass 278 Da), 17 six-ring isomers (molecular mass 328 Da), and 20 seven-ring isomers (molecular mass 378 Da). Significant linear correlations were found for all isomer groups (r = 0.71 to 0.94). Nonplanarity of the PAH isomers was found to influence retention (i.e., nonplanar isomers eluting earlier than expected based on L/B) and linear correlations of retention vs. T for isomer groups containing nonplanar isomers were significant (r = 0.71 to 0.86). Graphical abstract.

14.
Anal Bioanal Chem ; 410(17): 4177-4188, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29732496

ABSTRACT

The research described here provides the most comprehensive qualitative characterization of three combustion-related standard reference materials (SRMs) for polycyclic aromatic sulfur heterocycles (PASHs) and some alkyl-substituted (alkyl-) derivatives to date: SRM 1597a (coal tar), SRM 1991 (coal tar/petroleum extract), and SRM 1975 (diesel particulate extract). An analytical approach based on gas chromatography/mass spectrometry (GC/MS) is presented for the determination of three-, four-, and five-ring PASH isomers and three- and four-ring alkyl-PASHs in the three SRM samples. The benefit of using a normal-phase liquid chromatography (NPLC) fractionation procedure prior to GC/MS analysis was demonstrated for multiple isomeric PASH groups. Using a semi-preparative aminopropyl (NH2) LC column, the three combustion-related samples were fractionated based on the number of aromatic carbon atoms. The NPLC-GC/MS method presented here allowed for the following identification breakdown: SRM 1597a - 35 PASHs and 59 alkyl-PASHs; SRM 1991-31 PASHs and 58 alkyl-PASHs; and SRM 1975-13 PASHs and 25 alkyl-PASHs. These identifications were based on NPLC retention data, the GC retention times of reference standards, and the predominant molecular ion peak in the mass spectrum. Prior to this study, only 11, 1, and 0 PASHs/alkyl-PASHs had been identified in SRM 1597a, SRM 1991, and SRM 1975, respectively. Graphical abstract NPLC-GC/MS analysis for the three- and four-ring parent PASH isomers in SRM 1597a.

15.
Article in English | MEDLINE | ID: mdl-29855048

ABSTRACT

BACKGROUND: Culture-negative (CN) cardiovascular implantable electronic device (CIED) infections represent a significant management challenge for clinicians with no specific guidelines addressing this subgroup of patients. The aim of the current investigation is to report our institutional experience of CN CIED infections and propose a systematic approach to diagnostic evaluation and management of these complicated cases based on our observations. METHODS: We retrospectively screened all CIED infection cases at Mayo Clinic from 2005 through 2017. Using standardized criteria to define significant microbial growth, all patients with positive blood or pocket/device cultures were excluded. RESULTS: A total of 835 cases of CIED infection were screened, and of these, 47 (6%) met CN-CIED infection criteria. Majority of patients (77%) in this cohort had received antimicrobial therapy prior to device cultures with a median duration of 8 days. The most common presentation was device pocket infection (81%). All patients underwent device removal. Route of antibiotics was switched from oral to parenteral and spectrum of activity expanded from initial therapy in 23% of patients despite negative cultures. Majority of patients (80%) were dismissed on parenteral therapy. Adverse events attributed to intravenous antibiotic therapy were documented in 63% of the cases. No recurrence was reported and 6-month survival was 94.8%. CONCLUSIONS: Pocket and device cultures in suspected CIED infections may be negative due to preextraction oral antibiotics. However, frequently these patients are managed with broad-spectrum parenteral therapy postextraction.

16.
Clin Infect Dis ; 64(11): 1516-1521, 2017 Jun 01.
Article in English | MEDLINE | ID: mdl-28329125

ABSTRACT

BACKGROUND.: Most cardiovascular implantable electronic device (CIED) recipients are elderly, have multiple comorbid conditions, and are at increased risk of CIED infection (CIEDI). Current guidelines recommend complete device removal in patients with CIEDI to prevent relapse and mortality. However, comorbidities or other factors may preclude device removal, thus prompting a nonsurgical approach that includes chronic antibiotic suppression (CAS). There are limited data on outcomes of patients receiving CAS for CIEDI. METHODS.: We retrospectively screened 660 CIEDI cases from 2005 to 2015 using electronic health records and a CIEDI institutional database and identified 48 patients prescribed CAS. Primary outcomes were infection relapse and survival. RESULTS.: The median age was 78 years, and 73% (35/48) were male. The median Charlson comorbidity index was 4. Common pathogens were coagulase-negative staphylococci (21%, 10/48) and methicillin-sensitive Staphylococcus aureus (19%, 9/48). At 1 month after hospitalization, 25% (12/48) of patients had died, of whom only 1 initiated CAS; 67% (8/12) of these had staphylococcal infections. Of the 37 patients who initiated CAS, the most common antimicrobials were trimethoprim-sulfamethoxazole, penicillin, and amoxicillin (22%, 8/37 each). Estimated median overall survival was 1.43 years (95% confidence interval, 0.27-2.14), with 18% (6/33 survivors) developing relapse within 1 year. Of the 6 patients who relapsed, 2 (33%) subsequently underwent CIED extraction. CONCLUSION.: CAS is reasonable in select patients who are not candidates for complete device removal for attempted cure of CIEDI. Nevertheless, 1-month mortality in our sample of CAS-eligible patients was high and reflective of high rates of comorbid conditions.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Pacemaker, Artificial/microbiology , Prosthesis-Related Infections/drug therapy , Aged , Aged, 80 and over , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/adverse effects , Comorbidity , Device Removal , Electronic Health Records , Female , Humans , Male , Middle Aged , Prosthesis-Related Infections/microbiology , Prosthesis-Related Infections/mortality , Retrospective Studies , Risk Factors , Staphylococcal Infections/drug therapy , Staphylococcus aureus/isolation & purification , Treatment Outcome , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use
17.
Anal Bioanal Chem ; 409(21): 5171-5183, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28664340

ABSTRACT

A normal-phase liquid chromatography (NPLC) fractionation procedure was developed for the characterization of a complex mixture of polycyclic aromatic hydrocarbons (PAHs) from a coal tar sample (Standard Reference Material (SRM) 1597a). Using a semi-preparative aminopropyl (NH2) LC column, the coal tar sample was separated using NPLC based on the number of aromatic carbons; a total of 14 NPLC fractions were collected. SRM 1597a was analyzed before and after NPLC fractionation by using gas chromatography/mass spectrometry (GC/MS) with a 50% phenyl stationary phase. The NPLC-GC/MS method presented in this study allowed for the identification of 72 PAHs and 56 MePAHs. These identifications were based on the NPLC retention times for authentic reference standards, GC retention times for authentic reference standards, and the predominant molecular ion peak in the mass spectrum. Most noteworthy was the determination of dibenzo[a,l]pyrene, which could not be measured directly by GC/MS because of low concentration and co-elution with dibenzo[j,l]fluoranthene. The NPLC-GC/MS procedure also allowed for the tentative identification of 74 PAHs and 117 MePAHs based on the molecular ion peak only. This study represents the most comprehensive qualitative characterization of SRM 1597a to date. Graphical abstract NPLC-GC/MS analysis for the six-ring MM 302 Da PAH isomers in SRM 1597a.

18.
Anal Bioanal Chem ; 409(22): 5291-5305, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28717893

ABSTRACT

Retention indices for 124 polycyclic aromatic hydrocarbons (PAHs) and 62 methyl-substituted (Me-) PAHs were determined using normal-phase liquid chromatography (NPLC) on a aminopropyl (NH2) stationary phase. PAH retention behavior on the NH2 phase is correlated to the total number of aromatic carbons in the PAH structure. Within an isomer group, non-planar isomers generally elute earlier than planar isomers. MePAHs generally elute slightly later but in the same region as the parent PAHs. Correlations between PAH retention behavior on the NH2 phase and PAH thickness (T) values were investigated to determine the influence of non-planarity for isomeric PAHs with four to seven aromatic rings. Correlation coefficients ranged from r = 0.19 (five-ring peri-condensed molecular mass (MM) 252 Da) to r = -0.99 (five-ring cata-condensed MM 278 Da). In the case of the smaller PAHs (MM ≤ 252 Da), most of the PAHs had a planar structure and provided a low correlation. In the case of larger PAHs (MM ≥ 278 Da), nonplanarity had a significant influence on the retention behavior and good correlation between retention and T was obtained for the MM 278 Da, MM 302 Da, MM 328 Da, and MM 378 Da isomer sets. Graphical abstract NPLC separation of the three-, four-, five-, and six-ring PAH isomers with different number of aromatic carbon atoms and degrees of non-planarity (Thickness, T). The inserted figure plots the number of aromatic carbon atoms vs. the log I value for the 124 parent PAHs.

19.
J Stroke Cerebrovasc Dis ; 26(11): 2527-2535, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28673812

ABSTRACT

BACKGROUND: Brain magnetic resonance imaging (MRI) is frequently obtained in patients with infective endocarditis, yet its utility in predicting outcomes for valve replacement surgery in patients is unknown. The objective of this study was to determine how brain MRI findings impact clinical management and outcomes. METHODS: Demographic and clinical data from electronic medical records at Mayo Clinic were retrospectively reviewed for patients hospitalized with definite or possible infective endocarditis according to the modified Duke criteria between January 1, 2007 and December 31, 2014. There were 364 patients included in the study. RESULTS: Cardiac valve replacement surgery was performed in 195 of 364 (53.6%) patients, and 95 (48.7%) of the surgical patients underwent preoperative MRI, which was associated with preoperative neurologic symptoms in 56 of 95 (58.9%) patients (odds ratio = 12.92; 95% confidence interval, 5.98-27.93; P <.001). Postoperative neurologic complications occurred in 24 of 195 (12.3%) patients, including new ischemic stroke in 4 of 195 (2.1%) and new intracerebral hemorrhage in 3 of 195 (1.5%). No patients with microhemorrhages developed postoperative hemorrhage. No significant differences existed in rates of postoperative complications between patients with and those without preoperative MRI. There were no substantial associations between preoperative MRI findings and postoperative neurologic complications, functional outcomes as described by the modified Rankin Scale score, or 6-month mortality. CONCLUSIONS: In patients undergoing valve replacement surgery, preoperative MRI findings were not associated with differences in postoperative outcomes, irrespective of finding or timing of valve replacement surgery.


Subject(s)
Brain/diagnostic imaging , Cardiac Surgical Procedures/methods , Endocarditis/pathology , Endocarditis/surgery , Magnetic Resonance Imaging , Adult , Aged , Female , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Treatment Outcome
20.
Circulation ; 132(15): 1435-86, 2015 Oct 13.
Article in English | MEDLINE | ID: mdl-26373316

ABSTRACT

BACKGROUND: Infective endocarditis is a potentially lethal disease that has undergone major changes in both host and pathogen. The epidemiology of infective endocarditis has become more complex with today's myriad healthcare-associated factors that predispose to infection. Moreover, changes in pathogen prevalence, in particular a more common staphylococcal origin, have affected outcomes, which have not improved despite medical and surgical advances. METHODS AND RESULTS: This statement updates the 2005 iteration, both of which were developed by the American Heart Association under the auspices of the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease, Council on Cardiovascular Disease of the Young. It includes an evidence-based system for diagnostic and treatment recommendations used by the American College of Cardiology and the American Heart Association for treatment recommendations. CONCLUSIONS: Infective endocarditis is a complex disease, and patients with this disease generally require management by a team of physicians and allied health providers with a variety of areas of expertise. The recommendations provided in this document are intended to assist in the management of this uncommon but potentially deadly infection. The clinical variability and complexity in infective endocarditis, however, dictate that these recommendations be used to support and not supplant decisions in individual patient management.


Subject(s)
Anti-Infective Agents/therapeutic use , Endocarditis , Adult , Anti-Infective Agents/pharmacokinetics , Anticoagulants/therapeutic use , Bacteremia/complications , Bacteremia/diagnosis , Candidiasis/diagnosis , Candidiasis/therapy , Diagnostic Techniques, Cardiovascular/standards , Endocarditis/complications , Endocarditis/diagnosis , Endocarditis/microbiology , Endocarditis/therapy , Heart Valve Prosthesis/adverse effects , Heart Valve Prosthesis/microbiology , Humans , Prosthesis-Related Infections/diagnosis , Prosthesis-Related Infections/microbiology , Prosthesis-Related Infections/therapy , Rheumatic Heart Disease/complications , Risk Factors , Staphylococcal Infections/diagnosis , Staphylococcal Infections/drug therapy , Streptococcal Infections/diagnosis , Streptococcal Infections/drug therapy
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