bluuebunny/crossref_metadata_2025 huggingface dataset:
Tracking the roots of cellulase hyperproduction by the fungus
Trichoderma reesei
using massively parallel DNA sequencing
Authors: Le Crom Stéphane , Schackwitz Wendy , Pennacchio Len , Magnuson Jon K. , Culley David E. , Collett James R. , Martin Joel , Druzhinina Irina S. , Mathis Hugues , Monot Frédéric , Seiboth Bernhard , Cherry Barbara , Rey Michael , Berka Randy , Kubicek Christian P. , Baker Scott E. , Margeot Antoine
Published: September 2009

Trichoderma reesei
(teleomorph
Hypocrea jecorina
) is the main industrial source of cellulases and hemicellulases harnessed for the hydrolysis of biomass to simple sugars, which can then be converted to biofuels such as ethanol and other chemicals. The highly productive strains in use today were generated by classical mutagenesis. To learn how cellulase production was improved by these techniques, we performed massively parallel sequencing to identify mutations in the genomes of two hyperproducing strains (NG14, and its direct improved descendant, RUT C30). We detected a surprisingly high number of mutagenic events: 223 single nucleotides variants, 15 small deletions or insertions, and 18 larger deletions, leading to the loss of more than 100 kb of genomic DNA. From these events, we report previously undocumented non-synonymous mutations in 43 genes that are mainly involved in nuclear transport, mRNA stability, transcription, secretion/vacuolar targeting, and metabolism. This homogeneity of functional categories suggests that multiple changes are necessary to improve cellulase production and not simply a few clear-cut mutagenic events. Phenotype microarrays show that some of these mutations result in strong changes in the carbon assimilation pattern of the two mutants with respect to the wild-type strain QM6a. Our analysis provides genome-wide insights into the changes induced by classical mutagenesis in a filamentous fungus and suggests areas for the generation of enhanced
T. reesei
strains for industrial applications such as biofuel production.
C-end rule peptides mediate neuropilin-1-dependent cell, vascular, and tissue penetration
Authors: Teesalu Tambet , Sugahara Kazuki N. , Kotamraju Venkata Ramana , Ruoslahti Erkki
Published: September 2009

Screening of phage libraries expressing random peptides for binding to prostate cancer cells primarily yielded peptides that had a C-terminal arginine (or rarely lysine) residue, usually in a consensus context R/KXXR/K. Phage expressing these sequences and synthetic nanoparticles coated with them bound to and were internalized into cells. The C-terminal arginine (or lysine) was essential to the activity; adding another amino acid, or even blocking the free carboxyl group of this arginine residue by amidation, eliminated the binding and internalizing activity. An internal R/KXXR/K can be exposed and switched on by a cleavage by a protease. The strict requirement for C-terminal exposure of the motif prompted us to term the phenomenon the
C-end rule
(CendR). Affinity chromatography showed that the CendR peptides bind to neuropilin-1 (NRP-1) on the target cells. NRP-1 is a cell-surface receptor that plays an essential role in angiogenesis, regulation of vascular permeability, and the development of the nervous system. VEGF-A165 and other ligands of NRP-1 possess a C-terminal CendR sequence that interacts with the b1 domain of NRP-1 and causes cellular internalization and vascular leakage. Our CendR peptides have similar effects, particularly when made multivalent through coupling to a particle. We also noted a unique and important activity of these peptides: penetration and transportation through tissues. The peptides were able to take payloads up to the nanoparticle size scale deep into extravascular tissue. Our observations have implications in drug delivery and penetration of tissue barriers and tumors.
Influence of cell phone email use on characteristics of gait
Authors: Demura Shinichi , Uchiyama Masanobu
Published: September 2009

Previously, gait had been considered an automatic and rhythmical movement that uses minimal attentional resources. The relationship between attention and gait has been revealed in recent research. However, in young adults in particular, the influence of using a cell phone – which is used frequently in daily life and considered to require high attentional demands – on gait has not been demonstrated. In this study, we examined the influence of mobile phone use on gait. Thirty healthy college students (15 males, 15 females) walked through a normal straight course with or without an obstacle under two different walking conditions while either using the email function of the cell phone or walking without a cell phone. The participants walked at a normal speed on a 10‐m walkway. In walking conditions with an obstacle, an obstacle (17 cm in height) was set at the mid‐point of the walkway. The following gait parameters were calculated: velocity, stride length, stride width (cm), and stance phase of one foot (just before an obstacle, one and two steps before the obstacle). Velocity and stride width decreased and the stance phase increased during walking while operating a cell phone. The stance phase just before an obstacle and stride length increased while operating a cell phone with an obstacle in the way. Gaze fixations and the high attention required to use the email function of the device may result in greatly disturbed gait.
Relationship between heart rate variability and the serum testosterone‐to‐cortisol ratio during military service
Authors: Huovinen Jukka , Tulppo Mikko , Nissilä Juuso , Linnamo Vesa , Häkkinen Keijo , Kyrolainen Heikki
Published: September 2009

The autonomic nervous system and circulating hormones control a stress reaction through a complex interaction. We tested the hypothesis that changes in cardiac vagal regulation may be positively associated with the serum testosterone‐to‐cortisol ratio during the first week of military service in 24 conscripts aged 19.0±0.3 years. Cardiac autonomic function was assessed by measuring high‐frequency (HF: 0.15–0.4 Hz) and low‐frequency (LF: 0.04–0.15 Hz) power spectral indices of R‐R intervals during supine rest and during a controlled standing condition (5 min for both) from the second to the seventh mornings at the beginning of military service. Blood samples were collected to analyse the basal serum testosterone‐to‐cortisol ratio on the seventh morning. Changes in heart rate and high‐frequency power measured in the standing condition were positively correlated with the serum testosterone‐to‐cortisol ratio at day 7 (r= − 0.42 and r=0.45, respectively; P<0.05 for both). However, changes in low‐frequency power and LF/HF ratio did not correlate with testosterone or cortisol concentration. The present results suggest a relationship between changes in cardiac vagal regulation during a long‐term mentally stressful condition and the serum testosterone‐to‐cortisol ratio. This association was more marked during the controlled standing condition.
TCR-dependent differentiation of thymic Foxp3+ cells is limited to small clonal sizes
Authors: Leung Monica W.L. , Shen Shiqian , Lafaille Juan J.
Published: September 2009

Numerous studies have highlighted the importance of high-affinity interactions between T cell receptors (TCRs) and their ligands in the selection of Foxp3+ regulatory T cells (T reg cells). To determine the role of the TCR in directing T cells into the Foxp3+ lineage, we generated transgenic (Tg) mice expressing TCRs from Foxp3+ cells. Initial analyses of the TCR Tg mice crossed with RAG-deficient mice showed that the percentage of Foxp3+ cells was very low. However, intrathymic injection and bone marrow chimera experiments showed a saturable increase of the Foxp3+ population when T reg TCR Tg cells were present in low numbers. Furthermore, when analyzing whole thymi of T reg TCR Tg RAG-deficient mice, we found significantly more Foxp3+ cells than in conventional T cell TCR Tg mice. Our results indicate that although the TCR has an instructive role in determining Foxp3 expression, selection of Foxp3+ individual clones in the thymus is limited by a very small niche.
Restriction Endonuclease Analysis of Plasmid DNA From Methicillin-Resistant Staphylococcus aureus: Clinical Application Over a Three-Year Period
Authors: Trilla Antoni , Nettleman Mary D. , Hollis Richard J. , Fredrickson Mary , Wenzel Richard P. , Pfaller Michael A.
Published: September 2009

Objective:

To investigate trends in plasmid types of methicillin-resistant Staphylococcus aureus over a 3-year period and determine the clinical impact of plasmid typing.

Design:

Restriction endonuclease analysis of plasmid DNA (REAP) was used to type 270 clinical isolates.

Setting:

A Veterans Affairs Medical Center.

Results:

Forty-four different REAP types were identified and, of these, 23 appeared only once. Types designed as V1 and V2 were more commonly found in nosocomial cases than in community-acquired cases (p<.05); whereas the K and D types were more common in isolates from community-acquired cases (<c.05). In 30 (11%) isolates, no plasmid was detected. When combined with epidemiological data, REAP typing revealed 4 small outbreaks that would have been missed using traditional epidemiological methods alone. In large outbreaks involving 10 or more cases, REAP typing data revealed unsuspected patterns of transmission.

Conclusions:

Multiple plasmid types were present in this endemic setting. Restriction endonuclease analysis of plasmid DNA was a practical and valuable adjunct to traditional epidemiological methods.
Case-Control and Vector Studies of Nosocomial Acquisition of Pseudomonas Cepacia in Adult Patients with Cystic Fibrosis
Authors: Burdge David R. , Nakielna E.M. , Noble M.A.
Published: September 2009

Objective:

To examine factors associated with nosocomial acquisition of Pseudomonas cepacia in adult patients with cystic fibrosis.

Design:

A retrospective case-control study of 5 patients with nosocomial acquisition of P cepacia versus 20 matched controls who failed to develop P cepacia infection. Selective handwashing, air sampling, and respiratory equipment sampling also were performed.

Setting:

A university hospital providing tertiary care to 95 adult cystic fibrosis patients.

Patience:

All patients are adults with known cystic fibrosis. Case definition required multiple negative sputum cultures for P cepacia prior to and during admission, with a positive sputum culture prior to discharge. Controls had negative sputum cultures for P cepacia prior to and throughout hospitalization. Controls were matched for age, gender, disease severity, and frequency of hospitalizations.

Results:

Factors associated with increased risk of nosocomial acquisition of P cepacia included receiving humidifier or nebulized treatments (60% versus 5%, p = .016, odds ratio= 28.5, 95% confidence interval= 1.93 to 420.58). Factors without significance included ward, room, teaching versus nonteaching status, use of steroids, sharing a hospital room with another cystic fibrosis patient, antibiotic use, presence of portocath in situ, or socializing with another individual with cystic fibrosis known to be P cepacia -positive. Air sampling studies failed to demonstrate aerosolization of P cepacia by coughing cystic fibrosis patients over a 1-hour sampling time. Handwashing studies failed to demonstrate P cepacia on hands of cystic fibrosis patients, nurses, or physiotherapists (before or after physiotherapy). Reservoirs from nebulizers consistently grew P cepacia following therapy.

Conclusions:

Respiratory equipment may be an important source of nosocomial acquisition of P cepacia in adult cystic fibrosis patients.
Installing Needle Disposal Boxes Closer to the Bedside Reduces Needle-Recapping Rates in Hospital Units
Authors: Makofsky David , Cone James E.
Published: September 2009

Objective:

To compare the proportion of recapped needles, an injury surrogate measure, in disposal boxes on two different types of hospital units, both before and after an intervention.

Design:

Prospective nonrandomized intervention trial.

Setting:

A major public teaching hospital.

Participants:

Specific hospital units. We selected two types of hospital units for study: the first type of hospital unit (medical-surgical ward) had existing mounted in-bathroom needle disposal boxes, and the second type of hospital unit (intensive care unit) had unmounted needle disposal boxes in the room but not necessarily near the patient's bedside.

Intervention:

The installation, in the medical-surgical wards only, of mounted needle disposal boxes on the wall near the patient's bed. The box location in the intensive care units remained the same. In both types of unit, a new mailbox-slot disposal box (SAGE) also was substituted for the previous round-top container.

Results:

The baseline proportion of recapped needles in the first medical-surgical unit was 32.6% (±3.8%) and in the second medical-surgical unit it was 27.4% (± 4.0%) in the bathroom needle disposal boxes, which was similar to the observed proportion (34.7 ± 6.4%) in the intensive care unit boxes. Following the intervention, the proportion of recapped needles was significantly reduced in the disposal containers adjacent to the bedside in medical-surgical units, to 27% (a difference of 2.9 standard errors of the baseline distribution) in the first unit and 18.2% (a difference of 4.6 standard errors) in the second. In the intensive care unit, where boxes were not moved but new mailbox-types were simply substituted, no significant change was noted (36.6%, a difference of 0.59 standard errors). A statistically significant reduction was observed in the proportion of needles recapped in both wards combined following the intervention (30.2% to 26.2%, a difference of 2.9 standard errors).

Conclusion:

Environmental changes alone are an effective means of altering the risk to healthcare workers from sharp instruments. The use of needle-box counts provides a sensitive and stable instrument to measure injury surrogates and, indirectly, behavioral change in hospital workers.
Malaria Protection of the International Traveler
Authors: Rangel-Frausto M. Sigfrido , Edmond Michael B.
Published: September 2009

Although isolated cases of malaria still may be acquired in the United States,’ imported cases in international travelers are primarily responsible for approximately 1,000 cases reported annually to the Centers for Disease Control and Prevention (CDC). In the decade ending in 1988, more than 50 malaria-associated deaths were reported, most of them theoretically preventable. Moreover, it is estimated that only 30% to 60% of malaria cases are actually reported to the CDC.

In recent years, an increase in infections due to Plasmodium falciparum, which accounts for the most severe form of malaria, has been noted. This increase is multifactorial in origin and is associated with an increase in travel to malarious areas, difficulties with chemoprophylaxis (including compliance and adverse effects), and increasing resistance to multiple antimalarial agents. Thus, careful counseling of the traveler and appropriate chemoprophylaxis remain vitally important.
Puncture Injuries Due to Needles Removed From Intravenous Lines: Should the Source Patient Routinely be Tested for Bloodborne Infections?
Authors: Manian Farrin A. , Meyer Lynn , Jenne Joan
Published: September 2009

Objective:

To better assess the risk of exposure to bloodborne pathogens following puncture injuries due to needles removed from intravenous(IV) lines.

Setting:

Tertiary care community medical center.

Patients:

A convenience sample of hospitalized patients requiring IV piggy-back medications.

Methods:

Examination of 501 IV ports of peripheral lines, heparin-locks, and central venous lines for visible blood and testing the residual fluid in the needles removed from these ports for the presence of occult blood by using guaiac-impregnated paper.

Results:

The proximal ports of central venous lines and heparin-locks were statistically more likely to contain visible blood than proximal and distal ports of peripheral lines (17% and 20% versus 1% and 3% respectively, P<0.05). Similarly, needles removed from proximal ports of central venous lines and heparin-locks were statistically more likely to contain occult blood than those from peripheral lines ( 11% and 14% versus 2%, respectively, P<0.05). Only two needles removed from IV lines without visible blood contained occult blood: one from the proximal port of a central line and another from a heparin-lock. None of the needles from peripheral lines without visible blood contained occult blood.

Estimation of the risk of transmission of hepatitis B and C and human immunodeficiency virus (HIV) following injury by needles from various IV lines revealed that injury due to needles removed from peripheral IV lines and distal ports of central lines without visible blood was associated with “near zero” risk of transmission of these bloodborne infections at our medical center.

Conclusions:

Routine serological testing of source patients involving injury due to needles removed from peripheral IV lines and distal ports of central lines without visible blood is not necessary at our medical center. Conversely, due to the relatively high rate of occult blood in the needles removed from proximal ports of central venous lines and heparin-locks, puncture injuries due to these needles are considered significant and managed accordingly.
Methicillin-Resistant Staphylococcus aureus in a Nursing Home and Affiliated Hospital: A Four Year Prespective
Authors: Strausbaugh Larry J. , Jacobson Cleone , Yost Terri
Published: September 2009

Objectives:

To determine the effect of a methicillin-resistant Staphylococcus aureus (MRSA) outbreak in a nursing home on the subsequent MRSA caseload in a closely affiliated hospital.

Design:

Observational and descriptive; routine and special MRSA surveillance data for nursing home and hospital were reviewed for a four-year period (1988 to 1991) as were records regarding patient transfers from nursing home to hospital.

Setting:

The 120-bed nursing home care unit (NHCU) and the geographically separate 434-bed acute care facility (hospital) of the Portland Veterans' Affairs Medical Center (PVAMC).

Patients:

Veterans hospitalized in the acute care division of NHCU.

Results:

Following the introduction of MRSA into the NHCU in December 1987, it quickly disseminated. Two to 32 newly colonized or infected patients were recognized in each quarter of the study period. Facilitywide prevalence surveys on two occasions disclosed MRSA colonization rates of 34% and 10%. During the study period, 15 to 54 (mean: 37.6) patients were transferred each quarter from the NHCU to the hospital of the PVAMC. The number of MRSA cases transferred ranged from 0 to 16 per quarter (mean: 5.4). During the same period, the total number of MRSA cases in the hospital increased, rising from 7 cases in 1987 to 16 in 1988, 48 in 1989, 34 in 1990, and 35 in 1991. The percentage of hospital MRSA cases accounted for by NHCU transfers was 0% in 1988, 38% in 1989, 12% in 1990, and 11% in 1991.

Conclusions:

Despite the steady flow of patients between the NHCU and the hospital, the MRSA outbreak in the NHCU was associated with only a modest increase in the MRSA caseload at the affiliated hospital.
Managing Occupational Exposures to HIV-1 in the Healthcare Workplace
Authors: Fahey Barbara J. , Beekmann Susan E. , Schmitt James M. , Fedio Joan M. , Henderson David K.
Published: September 2009

Managing occupational exposures to human immunodeficiency virus type 1 (HIV-1) in the healthcare workplace remains both controversial and complex. Healthcare workers' perceptions of risk for occupational transmission of HIV-1, their knowledge of risk-reduction strategies, and their perceptions about appropriate postexposure management are all derived from an intricate interplay of scientific, political, social, and emotional sources. Following an occupational exposure to blood or blood-containing body fluids, a healthcare worker's immediate emotional response may be extreme gut-wrenching anxiety, with perceptions often biased by ignorance, uncertainty, and fear. The healthcare worker's postinjury emotional and psychological stress can be extraordinary; postinjury therapy, of necessity, must integrate medical, physical, psychological, and psychosocial aspects of care. Clinical decisions regarding HIV-1 injury management, therefore, are based not only on available scientific and medical information but also on measured actions designed to manage and presumably to diminish the profound anxiety almost invariably associated with an occupational exposure to HIV-1. In stark contrast to this common and extreme emotional reaction, the likelihood of disease transmission from such occupational exposures is relatively small.

In this article, we will discuss a series of questions and issues typically encountered when a healthcare worker sustains an occupational exposure to HIV-1.
Risk Factors for Urinary Lithotripsy-Associated Sepsis
Authors: Orenstein Robert , Bross James E. , Dahlmann Mary
Published: September 2009

Objectives:

To identify risk factors for sepsis following urinary extracorporeal shock wave lithotripsy (ESWL).

Design:

Retrospective case-control study with two control groups.

Setting:

A rural, 570-bed, regional referral center.

Results:

Six cases (four bacteremias and two fungemias) were compared with two sets of 18 controls. Cases had a higher frequency and number of urinary tract infections prior to the procedure and tended to have larger stone size.

Conclusions:

Patients undergoing ESWL who are at high risk for infectious complications may be identified by preprocedure evaluation. Such patients may require alternative prophylactic regimens and close postprocedure follow-up.
Hand Dexterity in Hospital Personnel with Multiple Needlestick Injuries
Authors: Casanova J.E. , Barnas G.P. , Gollup J. , Schmitt S. , Casanova J.S.
Published: September 2009

Objective:

To test the hypothesis that multiple needlestick injuries in hospital employees may he due to intrinsic deficits in hand dexterity.

Design:

A case-control study comparing employees with multiple reported needlestick injuries to those with none. Hand dexterity was tested using the Purdue Pegboard Test, a standardized validated test of hand dexterity.

Setting:

A 300-bed, acute care teaching hospital.

Participants:

Fifteen hospital employees who sustained four or more injuries were compared to 19 controls.

Results:

No differences were detected in hand dexterity between the case and control groups.

Conclusions:

While employees with multiple needlestick injuries accounted for 85% of reported injuries, underlying factors responsible for injuries in this high-risk subgroup do not include measurable deficits in hand dexterity.
Epidemiology of Antiobiotic Use in a Neonatal Intensive Care Unit
Authors: Fonseca Silvia N.S. , Ehrenkranz Richard A. , Baltimore Robert S.
Published: September 2009

Objective:

To determine the incidence and pattern of antibiotic use in a neonatal intensive care unit (NICU).

Design:

Prospective study of a one-month NICU cohort. Investigators visited each subject, checking nursing notes, antibiotic flow sheets, and laboratory data at each daily visit.

Setting:

The NICU at Yale-New Haven Hospital, New Haven, Connecticut; a regional care, level 3 unit in a tertiary care medical center.

Patients:

All infants admitted to the NICU for one month (n = 63) who resided in the unit for ≥ 24 hours.

Results:

75% of the infants had antibiotic treatment begun in the first 48 hours of life. The highest rate of antibiotic treatment starts was in premature infants with birthweight less than 1,500 g, 92% of whom received antibiotics in the first 48 hours. In the subsequent days of life the incidence of starting antibiotic treatment was low and sporadic and the prevalence of antibiotic treatment by day of life showed a sharp decline between the third and fourth days of life. Five cross-sectional studies in the nursery showed point-prevalence rates of antibiotic use to be 27% to 43% of the whole NICU population, highest in the intensive care sector of the unit and in those <72 hours of age.

Conclusions:

The high incidence of antibiotic starts in this NICU was largely the result of universal treatment of premature infants beginning on the first day of life. The risk of infection in these infants is quite low; more information is needed concerning how to distinguish infants who do not require treatment. This study provides comparison data for NICUs compiling data on incidence and prevalence of antibiotic use and developing programs to limit antibiotic use.
Ten Years of Prospective Clostridium difficile-Associated Disease Surveillance and Treatment at the Minneapolis VA Medical Center, 1982–1991
Authors: Olson Mary M. , Shanholtzer Carol J. , Lee James T. , Gerding Dale N.
Published: September 2009

Objectives:

To understand the epidemiology, risks, and management of Clostridium difficile -associated disease (CDAD) and to establish and evaluate reliable methods of surveillance.

Design:

Case finding was done by daily ward and laboratory rounds. The criteria for CDAD diagnosis were: at least four unformed stools per day for 2 days and a positive culture or cytotoxin for C difficile, or positive endoscopy or autopsy for pseudomembranes.

Setting:

The surveillance covered all patients from 1982 through 1991 in the 820-bed Minneapolis Veterans Affairs Medical Center.

Participants:

The criteria were met by 908 patients. Medical service patients numbered 488; surgical patients, 420. Frequencies ranged from a high of 149 cases in 1982 to a low of 50 cases in 1989.

Results:

Stool specimens were obtained on 898 (99%) of the 908 CDAD patients. Stools were culture-positive in 864 (96%) of 898, cytotoxin-positive in 569 (63%) of 898. Endoscopy was performed on 196 (22%) of the 908 patients, and 80 (41%) of 196 patients had pseudomembranes. Ten (1%) of the 908 patients were diagnosed by endoscopy without a stool specimen, or at autopsy. No treatment was needed for 135 (15%) of the 908 CDAD patients, and 19 (2%) of the 908 died before treatment was started. Oral metronidazole was the treatment for 632 (70%) of 908 patients (1% intolerance, 2% failure, 7% relapse) and oral vancomycin was given to 122 (13%) of 908 patients (1% intolerance, 1% failure, 10% relapse). Twelve patients had pseudomembranous colitis at autopsy, and it was the primary cause of death in 5 (0.6%) of 908.

Conclusions:

CDAD usually responds to oral metronidazole or vancomycin but is nonetheless responsible for a high morbidity and occasional mortality in patients even when the diagnosis and treatment are pursued aggressively.
Management of Healthcare Workers Exposed to Pertussis
Authors: Rutala William A. , Weber David J.
Published: September 2009

The epidemiology of pertussis has changed in recent years. First, pertussis in adults is far more common than previously thought. Second, in many instances, the disease in adults is atypical or asymptomatic. Third, adult pertussis occurs despite a prior history of full immunization and, indeed, in persons with a prior history of natural disease.

Large outbreaks of pertussis have occurred in healthcare facilities through failure to recognize and isolate infected infants and children, failure to recognize and treat disease in staff members, and failure to institute control measures rapidly. Appropriate use of work restriction and erythromycin prophylaxis may decrease the likelihood of institutional outbreaks
Mortality Attributable to Nosocomial Infections in the ICU
Authors: Fagon Jean-Yves , Novara Ana , Stephan François , Girou Emmanuelle , Safar Michel
Published: September 2009

Although a direct relationship between nosocomial infection and mortality in intensive care unit (ICU) patients has not always been demonstrated formally, it is possible to conclude that nosocomial infections increase the risk of death in critically ill patients. A more precise analysis indicates that: 1) this effect is highly probable for pneumonia, doubtful for bacteremia, and uncertain for urinary tract infection; 2) risk increases with duration of stay in the ICU; 3) bacterial etiology modifies the risk; and 4) this effect is stronger in less severely ill patients, probably because the severity of underlying disease remains the most significant factor.
Viewpoint: Survival Benefit by Selective Decontamination of the Digestive Tract (SDD)
Authors: van Saene H.K.F. , Nunn A.J. , Petros A.J.
Published: September 2009

Morbidity and mortality due to infection acquired either before or after admission to the intensive care unit is still a major problem. A limited range of potentially pathogenic microorganisms (PPM) are involved, and infection with these PPM usually follows a predictable pattern. Selective decontamination of the digestive tract (SDD) should be investigated further in patients with primarily curable diseases who are not infected on admission to intensive care but become infected there.
Infectious Risk Factors Related to Operating Rooms
Authors: Pittet Didier , Ducel Georges
Published: September 2009

Risk factors related to operating rooms include patient-associated risks, the operating room environment, ventilation systems, cleansing and sterilization, and operating room personnel. Although constantly debated, surgical wound infection surveillance with appropriate feedback to surgeons is one of the few effective measures that helps reduce surgical infection rates, and we strongly recommend its use. We also recommend the further study of other potential components of effective infection control programs for surgical patients.
Do Intensive Hospital Antibiotic Control Programs Prevent the Spread of Antibiotic Resistance?
Authors: McGowan John E.
Published: September 2009

The relation between antibiotic control and resistance was assessed by review of selected journal articles from 1988 through 1994. Most studies of control or monitoring do not report susceptibility pattern as an outcome measure. Several aspects of bias and confounding prevent more than analysis of temporal association between antibiotic use restriction and resistance pattern. However, in a few institutions there has been an increase in susceptibility to antimicrobials following intensive control or monitoring. Moreover, in a few hospitals, intensive antibiotic control for selected drug-organism pairs was associated with a high prevalence of susceptibility, and the proportion susceptible fell abruptly when control or monitoring was relaxed or removed. These examples, coupled with the recent emergence of new resistant organisms, justify attempts to determine the value of intensive antibiotic control as a preventive practice. Because these studies were performed in single institutions, their power to distinguish associations was poor. Cooperative multicenter studies are needed in which selection and classification biases are addressed prospectively, and in which confounding factors are controlled.
Applications of Molecular Methods to Epidemiologic Investigations of Nosocomial Infections in a Pediatric Hospital
Authors: Bingen Edouard
Published: September 2009

Molecular typing methods are highly discriminatory for strains that cannot be separated by phenotypic methods. They are especially suited to monitoring outbreaks in children's hospitals. In many cases, molecular typing has improved the understanding of the mechanism of nosocomial acquisition of organisms by allowing distinction between endogenous and exogenous infections. Among exogenous infections, it has distinguished between individual and epidemic strains, thus differentiating cross-infection from independent acquisition.
Infectious Diseases and Death Among Nursing Home Residents: Results of Surveillance in 13 Nursing Homes
Authors: Beck-Sague Consuelo , Villarino Elsa , Giuliano Diane , Welbel Sharon , Latts Lisa , Manangan Lilia M. , Sinkowitz Ronda L. , Jarvis William R
Published: September 2009

An increasing proportion of the U.S. population resides in nursing homes (NHs). No surveillance system exists for infections in these facilities. To determine the incidence and types of infections in NH residents, and to identify predictors of death among residents with infections, we initiated a surveillance system at 13 NHs in California during a 6-month period from October 1989 through March 1990. The study included 1,754 residents, among whom 835 infections were identified during the study period. The most common infections were urinary tract infections (UTIs; 286, 34.2%), respiratory tract infections (RTIs; 259, 31%), and skin infections (150,17.9%). Of the 259 residents with respiratory tract infections, 69 (27%) had pneumonia. Antimicrobials were prescribed for 646 (77%) of the infectious episodes. Residents with pneumonia were more likely to die than residents with other infections (4 of 69 versus 12 of 766; P=0.04). Symptoms of altered body temperature (fever, hypothermia, chills) and change in mental status also were associated with an increased risk of a fatal outcome (10 of 260 versus 6 of 575; P= 0.01) and (7 of 127 versus 9 of 708; P= 0.004). This study suggests that the most common infections among NH residents are UTIs, RTIs, and skin infections. Pneumonia, symptoms of fever, and mental status changes all were associated with increased mortality. The frequency of infections among NH residents and their impact on resident outcome highlights the need for infectious disease surveillance in this population.
Changing Patterns of Mycobacterial Disease at a Teaching Community Hospital
Authors: Cox Jeffrey N. , Brenner Eric R. , Bryan Charles S.
Published: September 2009

Objectives:

To evaluate trends in the occurrence and diagnosis of mycobacterial disease.

Design:

Prospective surveillance study using a central tuberculosis registry at a 611-bed teaching community hospital.

Results:

Data pertaining to 715 patients were entered into the registry between 1976 and 1991 on the basis of positive smears or cultures for acid-fast bacilli (AFB). Over time, the ratio of isolates of Mycobacterium tuberculosis to isolates of nontuberculous mycobacteria reversed (from 3.2 to 1 between 1976 and 1981 to 1 to 1.6 between 1986 and 1991). The sensitivity of the sputum AFB smear for diagnosis of pulmonary tuberculosis increased (from 0.73 to 0.96), but the positive predictive value of the sputum AFB smear declined (from 0.72 to 0.59). The acquired immunodeficiency syndrome epidemic accounted for these changes only to a small extent.

Conclusions:

The increasing occurrence of non-tuberculous mycobacterial disease and the declining positive predictive value of the sputum AFB smear at this hospital imply that respiratory isolation and antituberculous therapy will be used inappropriately for many patients. The development and use of newer tests for early isolation and specific identification of M tuberculosis should be accelerated.
Plasmid DNA Profiles of Acinetobacter Baumannii: Clinical Application in a Complex Endemic Setting
Authors: Seifert Harald , Boullon Bertil , Schulze Andrea , Pulverer Gerhard
Published: September 2009

Objective:

To study the epidemiological, microbiological, and clinical features of infections due to Acinetobacter baumannii in a complex endemic situation over an 18-month period and to determine the clinical usefulness of plasmid DNA analysis of A baumannii in epidemiological investigations.

Design:

Review of medical and laboratory records. Antibiotic resistance patterns, biotyping, and plasmid profile analysis were used to characterize clinical and environmental isolates. Pulsed-field gel electrophoresis (PFGE) of chromosomal DNA was performed to verify results obtained with the other typing methods.

Setting:

Four different intensive care units of an 800-bed tertiary care center in Cologne, Germany.

Results:

240 patients were colonized or infected with A baumannii during the study period. No seasonal variations were observed. The majority of isolates (53%) were recovered from the respiratory tract. Major infections occurred in 61 patients; these included 48 bacteremias and eight pulmonary infections. Five different epidemic strains were identified: one each was A baumannii biotype 2 and 6, and three were biotype 9. A baumannii biotype 9 accounted for the vast majority of isolates (88%), which were clustered into three epidemic strains demonstrating distinct plasmid profiles. Two of these were considered genetically related as shown by PFGE. Epidemic strains were multidrug resistant, being uniformly susceptible to imipenem only. An epidemiological investigation failed to identify any point source of infection. Barrier precautions and improved handwashing were instituted in three of the four units and significantly reduced the incidence of colonization and infection in these units. Attack rates remained unchanged, however, in the burn unit where control measures were not implemented.

Conclusion:

Acinetobacter strains representing multiple biotypes and plasmid types were present in this endemic setting. Multidrug resistance in A baumannii is an important concern. Plasmid DNA analysis proved to be useful in epidemiological typing of A baumannii strains and may serve as a complementary typing system to traditional epidemiological methods.
Nosocomial Legionellosis Associated with Aspiration of Nasogastric Feedings Diluted in Tap Water
Authors: Venezia Richard A. , Agresta Marjorie D. , Hanley Eileen M. , Urquhart K. , Schoonmaker D.
Published: September 2009

Problem:

Two cases of nosocomial legionellosis due to Legionella pneumophila serogroup 6 (Lp6) were identified in the intensive care unit. Both patients had a history of aspiration of nasogastric tube feedings, developed pulmonary infiltrates, had positive cultures for Lp6, had serological titer rises to Legionella, were treated, and recovered.

Method:

Isolates of Lp6 from the potable water system and patients were characterized by DNA restriction enzyme analyses using pulsed-field gel electrophoresis (PFGE).

Results:

Water samples grew >1O4 CFU/L of Lp6, and the same PFGE pattern was observed with the patient and water isolates. Potable water was used only for delivering medications and diluting feeding solutions given through the nasogastric tubes of the patients. Heat shock of the hot water system (140° to 160°F or 60° to 7O°C, 4 hours) was performed and the temperature was maintained between 131° to 140°F (55° to 60°C). Surveillance over 18 months revealed a reduction in Legionella to <102 CFU/L.

Conclusion:

We speculate that nosocomial Legionella pneumonia occurred due to aspiration of nasogastric tube solutions diluted with tap water. A nursing practice change to use only sterile water to dilute feedings and flush medications for nasogastric administration was instituted. The hot water temperature at the faucet was increased to ≥131°F (≥60°C) to control Legionella. No further nosocomial cases have occurred.
The Use of Molecular Typing Techniques in the Epidemiologic Investigation of Resistant Enterococci
Authors: Willey Barbara M. , McGeer Allison J. , Ostrowski Mario A. , Kreiswirth Barry N. , Low Donald E.
Published: September 2009

The Enterococcus has become an important nosocomial pathogen despite its low virulence. From 1986 to 1989, the National Nosocomial Infections Surveillance System (NNIS) reported enterococci to be the third most common pathogen associated with bloodstream infections and the second most commonly isolated pathogen overall. This is due in part to the organism's ubiquitous nature and inherent antimicrobial resistance.

Enterococcus faecalis is found in the stool of virtually all adults at concentrations in excess of 106 colony-forming units/g. Enterococcus faecium, the second most common species causing human infection, is found at lesser concentrations in the stool of approximately 25% of healthy adults. Enterococci also can be isolated from the mouth, anterior urethra, groin, and vagina.
Improving Hepatitis B Vaccination Rates Among Surgeons
Authors: Manian Farrin A.
Published: September 2009

To improve hepatitis B vaccination among surgeons at our medical center, we instituted a program by which the surgeons were updated regarding vaccine safety and efficacy, and the cost of the vaccine and its administration at “strategic” locations was underwritten by the hospital. The rate of hepatitis B vaccination among surgeons increased from 62% to 89% based on pre- and postintervention surveys.
Contaminated Disinfectants in Health Clinics in Ilorin, Nigeria
Authors: Olayemi A.B. , Obayan Y.
Published: September 2009

Five of 18 samples of working dilutions of disinfectants used in the University of Ilorin Teaching Hospital, the University Clinic, and three other urban medical centers were found to be contaminated with bacteria. The results confirmed that disinfectants in storage support the growth of infectious agents, underlining the need to use fresh preparations of disinfectants.
Influenza and Pneumococcal Vaccination and Tuberculin Skin Testing Programs In Long-Term Care Facilities: Where Do We Stand?
Authors: McArthur Margaret A. , Simor Andrew E. , Campbell Beverly , McGeer Allison
Published: September 2009

Objectives:

1) To compare policies and procedures for distribution of influenza and pneumococcal vaccines to long-term care facilities for the elderly in Canada, 2) to determine vaccination rates of residents and staff, and 3) to describe vaccination and tuberculin skin testing programs in these facilities.

Design:

A cross-sectional survey consisting of telephone interviews and a mailed questionnaire was conducted in the spring of 1991. Telephone interviews were conducted with provincial/territorial epidemiologists. The questionnaire was sent to all (N = 1,520) Canadian long-term care facilities for the elderly with ≥ 25 beds.

Results:

There were 1,270 responding facilities (84%). The mean overall influenza vaccination rate for residents was 78.5%. The mean vaccination rate was higher in those provinces in which the vaccine was paid for by the government (79% versus 71%; P= 0.002). Only 19% of facilities reported staff vaccination rates >25%; rates again were higher in those provinces in which vaccine for staff was provided by the government. Pneumococcal vaccine was offered to residents in 12% of the facilities. The proportions of facilities with >10% and >75% of residents vaccinated were significantly higher in the provinces where the pneumococcal vaccine was recommended and paid for as compared with those where it was not (P<0.001 for both). Tuberculin skin testing programs for residents existed in 360 long-term care facilities (28%) across the country.

Conclusion:

In 1990, the number of residents living in Canadian long-term care facilities who were vaccinated against influenza and Streptococcus pneumoniae was suboptimal. Staff influenza vaccination rates were very low across the country. Most facilities did not have a baseline tuberculin skin test status for their residents. Vaccination rates are higher in jurisdictions in which governments provide the vaccine without charge.
Joint Commission on Accreditation of Healthcare Organizations
Authors: Patterson Carole H.
Published: September 2009

The Joint Commission on Accreditation of Healthcare Organizations was founded in 1951 as a private, not-for-profit organization that evaluates and accredits hospitals and other healthcare organizations. In 1987, the JCAHO launched its Agenda for Change to create a more modem and sophisticated accreditation process to place primary emphasis on actual performance. Coincident with this new emphasis, a number of task forces were established, including two for infection control standards.
An Outbreak of Needlestick Injuries in Hospital Employees Due to Needles Piercing Infectious Waste Containers
Authors: Anglim Anne M. , Collmer June E. , Loving T. Joel , Beltran Kenneth A. , Coyner Betty J. , Adal Karim , Jagger Janine , Sojka Nikolas J. , Farr Barry M.
Published: September 2009

Objectives:

To investigate the cause of an outbreak of needlestick injuries (NSIs) in hospital employees.

Setting:

A 700-bed university hospital.

Design:

Outbreak investigation, laboratory evaluation of a medical waste disposal device, cost analysis.

Methods:

Employee health department records were reviewed of workers suffering sticks from needles piercing fiberboard-contaminated material containers (CMCs). A laboratory evaluation of needle-puncture resistance properties of the CMCs was performed using a testing apparatus. The cost of a hospital waste disposal program using fiberboard CMCs was compared with the cost of a program using rigid plastic (polypropylene) boxes.

Results:

During 40 months of surveillance in 1986 and from 1989 to 1991, only one NSI had occurred from a needle piercing a CMC. During 9 months in 1993, 13 NSIs occurred due to needles piercing CMCs (P<.001). No clinical illness resulted from the NSIs. The outbreak was halted by a temporary change to plastic (polypropylene) boxes for sharps disposal ($4.92 to $23.33/cu ft) until receipt of a box with a newly designed solid fiberboard liner ($1.25/cu ft). CMC liners used during the epidemic had a mean needle puncture resistance of 527 g, as compared with 660 g for liners used before the outbreak (P<.001). The new solid fiberboard liner has a mean puncture resistance of 1,765 g. A program of waste disposal using fiberboard CMCs was found to cost approximately one-seventh the cost of a program using plastic boxes for disposal of infectious waste.

Conclusion:

A program for infectious waste disposal using fiberboard CMCs can be safe and cost-effective if appropriate standards for puncture resistance are met.
Recovery of Vancomycin-Resistant Enterococci on Fingertips and Environmental Surfaces
Authors: Noskin Gary A. , Stosor Valentina , Cooper Isabell , Peterson Lance R.
Published: September 2009

Objective:

To determine the recovery of vancomycin-resistant enterococci (VRE) on fingertips, gloved fingertips, and environmental surfaces commonly encountered in the healthcare setting, and to examine the importance of handwashing on the removal of these organisms.

Design:

Two clinical isolates of VRE (Enterococcus faecalis and Enterococcus faecium) were inoculated onto the hands of healthy human volunteers and the following environmental surfaces: countertops, bedrails, telephones, and stethoscopes. Following inoculation, samples were obtained at various time intervals to determine rates of recovery of organisms. To evaluate the effects of handwashing on enterococcal recovery, two different soap preparations were tested. Hands were washed with water alone or with one of the soaps and water. The soap and water studies were performed with a 5-second and a 30-second wash.

Results:

Both enterococcal strains survived for at least 60 minutes on gloved and ungloved fingertips. The E faecalis was recoverable from countertops for 5 days; the E faecium persisted for 7 days. For bedrails, both enterococcal species survived for 24 hours without significant reduction in colony counts. The bacteria persisted for 60 minutes on the telephone handpiece and for 30 minutes on the diaphragmatic surface of the stethoscope. A 5-second wash with water alone resulted in virtually no change in recovery of enterococci; a 30-second wash with water plus either soap was necessary to eradicate the bacteria from hands completely.

Conclusion:

VRE are capable of prolonged survival on hands, gloves, and environmental surfaces. Hands should be washed thoroughly and gloves removed following contact with patients infected or colonized with these multidrug-resistant bacteria. Finally, environmental surfaces may serve as potential reservoirs for nosocomial transmission of VRE and need to be considered when formulating institutional infection control policies.