Alden Research Laboratory

Holden, MA, United States

Alden Research Laboratory

Holden, MA, United States

Alden Research Laboratory, Inc. was founded in 1894 as part of Worcester Polytechnic Institute . It is the oldest continuously operating hydraulic laboratory in the United States. Today, as an independent entity, Alden has become a recognized leader in the field of fluid dynamics research and development. Wikipedia.

Time filter
Source Type

Brook I.,Georgetown University | Wexler H.M.,Greater Los Angeles Veterans Administration Healthcare System | Wexler H.M.,University of California at Los Angeles | Goldstein E.J.C.,University of California at Los Angeles | Goldstein E.J.C.,Alden Research Laboratory
Clinical Microbiology Reviews | Year: 2013

Susceptibility testing of anaerobic bacteria recovered from selected cases can influence the choice of antimicrobial therapy. The Clinical and Laboratory Standards Institute (CLSI) has standardized many laboratory procedures, including anaerobic susceptibility testing (AST), and has published documents for AST. The standardization of testing methods by the CLSI allows comparisons of resistance trends among various laboratories. Susceptibility testing should be performed on organisms recovered from sterile body sites, those that are isolated in pure culture, or those that are clinically important and have variable or unique susceptibility patterns. Organisms that should be considered for individual isolate testing include highly virulent pathogens for which susceptibility cannot be predicted, such as Bacteroides, Prevotella, Fusobacterium, and Clostridium spp.; Bilophila wadsworthia; and Sutterella wadsworthensis. This review describes the current methods for AST in research and reference laboratories. These methods include the use of agar dilution, broth microdilution, Etest, and the spiral gradient endpoint system. The antimicrobials potentially effective against anaerobic bacteria include beta-lactams, combinations of beta-lactams and beta-lactamase inhibitors, metronidazole, chloramphenicol, clindamycin, macrolides, tetracyclines, and fluoroquinolones. The spectrum of efficacy, antimicrobial resistance mechanisms, and resistance patterns against these agents are described. © 2013, American Society for Microbiology. All Rights Reserved.

Abrahamian F.M.,University of California at Los Angeles | Abrahamian F.M.,View Medical | Goldstein E.J.C.,University of California at Los Angeles | Goldstein E.J.C.,Alden Research Laboratory
Clinical Microbiology Reviews | Year: 2011

The microbiology of animal bite wound infections in humans is often polymicrobial, with a broad mixture of aerobic and anaerobic microorganisms. Bacteria recovered from infected bite wounds are most often reflective of the oral flora of the biting animal, which can also be influenced by the microbiome of their ingested prey and other foods. Bacteria may also originate from the victim's own skin or the physical environment at the time of injury. Our review has focused on bite wound infections in humans from dogs, cats, and a variety of other animals such as monkeys, bears, pigs, ferrets, horses, sheep, Tasmanian devils, snakes, Komodo dragons, monitor lizards, iguanas, alligators/crocodiles, rats, guinea pigs, hamsters, prairie dogs, swans, and sharks. The medical literature in this area has been made up mostly of small case series or case reports. Very few studies have been systematic and are often limited to dog or cat bite injuries. Limitations of studies include a lack of established or inconsistent criteria for an infected wound and a failure to utilize optimal techniques in pathogen isolation, especially for anaerobic organisms. There is also a lack of an understanding of the pathogenic significance of all cultured organisms. Gathering information and conducting research in a more systematic and methodical fashion through an organized research network, including zoos, veterinary practices, and rural clinics and hospitals, are needed to better define the microbiology of animal bite wound infections in humans. © 2011, American Society for Microbiology. All Rights Reserved.

Goldstein E.J.C.,Alden Research Laboratory | Goldstein E.J.C.,University of California at Los Angeles | Citron D.M.,Alden Research Laboratory | Tyrrell K.L.,Alden Research Laboratory
Antimicrobial Agents and Chemotherapy | Year: 2014

We determined the comparative activity of SMT19969 (SMT) against 162 strains representing 35 well-characterized Clostridium species in clusters I to XIX and 13 Clostridium species that had no 16S rRNA match. SMT MICs ranged from 0.06 to>512 g/ml and were not species related. SMT might have less impact on normal gut microbiota than other Clostridium difficile infection (CDI) antimicrobials. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Citron D.M.,Alden Research Laboratory | Tyrrell K.L.,Alden Research Laboratory | Goldstein E.J.C.,Alden Research Laboratory | Goldstein E.J.C.,University of California at Los Angeles
Diagnostic Microbiology and Infectious Disease | Year: 2014

Due to a high rate of relapse, osteomyelitis remains difficult to treat, requiring prolonged parenteral therapy. MICs for 41 consecutive Staphylococcus species recovered from patients with osteomyelitis were determined for dalbavancin, daptomycin, doxycycline, levofloxacin, linezolid, vancomycin, trimethoprim-sulfamethoxazole, rifampin, and vancomycin. Strains of vancomycin-intermediate Staphylococcus aureus (VISA) and heteroresistant VISA were included for additional comparison. Except for rifampin, dalbavancin was the most active agent tested. Dalbavancin is given once a week, making treatment of infections such as osteomyelitis potentially more convenient and thus could help reduce the rate of hospitalizations and outpatient costs. © 2014 Elsevier Inc.

Achermann Y.,University of Maryland, Baltimore | Goldstein E.J.C.,Alden Research Laboratory | Goldstein E.J.C.,University of California at Los Angeles | Coenye T.,Ghent University | Shirtliffa M.E.,University of Maryland, Baltimore
Clinical Microbiology Reviews | Year: 2014

Propionibacterium acnes is known primarily as a skin commensal. However, it can present as an opportunistic pathogen via bacterial seeding to cause invasive infections such as implant-associated infections. These infections have gained more attention due to improved diagnostic procedures, such as sonication of explanted foreign materials and prolonged cultivation time of up to 14 days for periprosthetic biopsy specimens, and improved molecular methods, such as broad-range 16S rRNA gene PCR. Implantassociated infections caused by P. acnes are most often described for shoulder prosthetic joint infections as well as cerebrovascular shunt infections, fibrosis of breast implants, and infections of cardiovascular devices. P. acnes causes disease through a number of virulence factors, such as biofilm formation. P. acnes is highly susceptible to a wide range of antibiotics, including beta-lactams, quinolones, clindamycin, and rifampin, although resistance to clindamycin is increasing. Treatment requires a combination of surgery and a prolonged antibiotic treatment regimen to successfully eliminate the remaining bacteria. Most authors suggest a course of 3 to 6 months of antibiotic treatment, including 2 to 6 weeks of intravenous treatment with a beta-lactam. While recently reported data showed a good efficacy of rifampin against P. acnes biofilms, prospective, randomized, controlled studies are needed to confirm evidence for combination treatment with rifampin, as has been performed for staphylococcal implant-associated infections. © 2014, American Society for Microbiology. All Rights Reserved.

Goldstein E.J.C.,Alden Research Laboratory | Goldstein E.J.C.,University of California at Los Angeles | Citron D.M.,Alden Research Laboratory | Tyrrell K.L.,Alden Research Laboratory | Merriam C.V.,Alden Research Laboratory
Antimicrobial Agents and Chemotherapy | Year: 2013

The comparative in vitro activity of SMT19969, a novel, narrow-spectrum, nonabsorbable agent, was studied against 50 ribotype-defined Clostridium difficile strains, 174 Gram-positive and 136 Gram-negative intestinal anaerobes, and 40 Gram-positive aerobes. SMT19969 was one dilution more active against C. difficile isolates (MIC range, 0.125 to 0.5 μg/ml; MIC90, 0.25 μg/ ml), including ribotype 027 strains, than fidaxomicin (range, 0.06 to 1 μg/ml; MIC90, 0.5 μg/ml) and two to six dilutions lower than either vancomycin or metronidazole. SMT19969 and fidaxomicin were generally less active against Gram-negative anaerobes, especially the Bacteroides fragilis group species, than vancomycin and metronidazole, suggesting that SMT19969 has a lesser impact on the normal intestinal microbiota that maintain colonization resistance. SMT19969 showed limited activity against other Gram-positive anaerobes, including Bifidobacteria species, Eggerthella lenta, Finegoldia magna, and Peptostreptococcus anaerobius, with MIC90s of>512, >512, 64, and 64 μg/ml, respectively. Clostridium species showed various levels of susceptibility, with C. innocuum being susceptible (MIC90, 1 μg/ml) and C. ramosum and C. perfringens being nonsusceptible (MIC90, >512 μg/ml). Activity against Lactobacillus spp. (range, 0.06 to>512 vg/ml; MIC90,>512 μg/ml) was comparable to that of fidaxomicin and varied by species and strain. Gram-positive aerobic cocci (Staphylococcus aureus, Enterococcus faecalis, E. faecium, and streptococci) showed high SMT19969 MIC90 values (128 to >512 μg/ml). Copyright © 2013, American Society for Microbiology. All Rights Reserved.

Goldstein E.J.C.,Alden Research Laboratory
Current Opinion in Infectious Diseases | Year: 2011

Purpose of review: Antibiotic therapy has the potential for intended as well as unintended consequences due to ecological effects that extend beyond the target pathogen. This review examines some of the collateral damage and collateral benefit that may occur when using antibiotic therapy. Recent findings: Antibiotics excreted in the gastrointestinal tract cause alterations of the indigenous flora. Such disruptions may increase the risk of colonization and overgrowth of pathogenic bacteria, including resistant species, with the potential for serious infection for an individual patient as well as possible hospital-wide dissemination resulting in local outbreaks of infection. For example, Clostridium difficile infection (CDI), and particularly associated diarrhea and colitis, is a potentially serious and growing problem in hospitals worldwide, and is associated with disruption of gut flora through use of broad-spectrum antibiotics, especially those with antianaerobic activity. Infection control measures and improved antibiotic stewardship are key measures for CDI prevention. Another example is the risk of intestinal colonization and overgrowth with resistant bacteria, which is heightened in surgical patients requiring antimicrobial therapy for intraabdominal infections. Results from two Optimizing Intra-Abdominal Surgery with Invanz studies (OASIS-I and OASIS-II) suggested emergence of resistant Enterobacteriaceae was less likely in these patients treated with ertapenem than in those treated with ceftriaxone/ metronidazole or piperacillin/tazobactam. Finally, recent studies have reported that increased use of a nonpseudomonal carbapenem such as ertapenem does not reduce the susceptibility of Pseudomonas aeruginosa to pseudomonal carbapenems, for example, imipenem or meropenem. In fact, data from one study showed increased ertapenem/decreased imipenem use was associated with improved susceptibility of P. aeruginosa to imipenem, probably due to decreased selective pressure for resistant species. Summary: Improper antibiotic use can be associated with detrimental effects related to the ecological impacts of these drugs. Improved antibiotic stewardship and appropriate infection control measures are key to minimization of the collateral damage associated with antibiotic therapy and may even have collateral benefits. © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins.

Citron D.M.,Alden Research Laboratory
Anaerobe | Year: 2012

Use of molecular techniques to characterize microorganisms during the past 20 years has increased the numbers of anaerobic species and made identification using only phenotypic methods difficult. Some of the newly described species have been recovered from blood cultures, showing pathogenic potential, and posing a challenge for identification. © 2011 Elsevier Ltd.

Goldstein E.J.C.,Alden Research Laboratory | Citron D.M.,Alden Research Laboratory
Clinical Microbiology Newsletter | Year: 2011

Despite the suggestions of both the Clinical and Laboratory Standards Institute (CLSI) and the American Society for Microbiology (ASM) Manual of Clinical Microbiology that hospitals should test individual patient isolates to assist in their care, periodically establish patterns of resistance for certain anaerobes, and include these data in the hospital antibiogram, anaerobic susceptibility studies are performed in only a minority of clinical laboratories and their patterns of susceptibility are obtainable mostly from published surveys conducted by a small number of research centers scattered worldwide. The Bacteroides fragilis group species, the most frequently studied anaerobes, have been reported to vary in their frequencies of resistance to all antimicrobial agents worldwide. Limited data exist about the resistance patterns of other genera and species. Part I of this two-part article reviews the methods used for anaerobic susceptibility testing and the correlation of in vitro susceptibility test results with clinical data and antimicrobial resistance that has been reported for gram-negative and gram-positive anaerobes. Part II of this article will review mechanisms of resistance among anaerobes to commonly used antimicrobial agents. © 2011 Elsevier Inc.

Citron D.M.,Alden Research Laboratory | Goldstein E.J.C.,Alden Research Laboratory
Diagnostic Microbiology and Infectious Disease | Year: 2011

This study evaluated the reproducibility and agreement of broth microdilution to agar dilution (AD) for testing CB-183,315, a novel lipopeptide antibiotic for Clostridium difficile. Reproducibility was 100% within ± one 2-fold dilution for 10 strains tested; agreement was 90-95% within one 2-fold dilution with AD for 103 clinical isolates. © 2011 Elsevier Inc.

Loading Alden Research Laboratory collaborators
Loading Alden Research Laboratory collaborators