Late surgical site infections among solid organ transplant recipients: an unrecognized clinical entity

This study identified 26 late invasive primary surgical site infection (IP-SSI) within 4-12 months of transplantation among 2073 SOT recipients at Duke University Hospital over the period 2015-2019. Thoracic organ transplants accounted for 25 late IP-SSI. Surveillance for late IP-SSI should be maintained for at least one year following transplant.

Cytomegalovirus Therapy: Role of Letermovir in Prophylaxis and Treatment in Transplant Recipients

Cytomegalovirus (CMV) is a common viral pathogen in the transplant population and is associated with significant morbidity and mortality. CMV prevention is paramount; however, selecting the best preventive strategy depends on many factors including donor-recipient CMV serostatus, transplant-specific risks, antiviral toxicities and cost. Novel CMV therapeutics such as letermovir (LTV) are desperately needed to optimize CMV management. Uniquely among CMV antiviral therapies, LTV inhibits the viral terminase complex in the CMV DNA synthesis pathway and disrupts viral genome packaging. Further, it lacks side effects frequently associated with other CMV antiviral therapies and evades common mechanisms of resistance. LTV is approved by the US Food and Drug Administration for CMV prevention in adult CMV-seropositive hematopoietic cell transplant recipients but is increasingly applied off-label for prophylaxis and treatment. This review summarizes important concepts of CMV management in transplantation, with a specific focus on LTV pharmacology and clinical experience to date alongside future prospects for its application.

The CLIP-170 N-terminal domain binds directly to both F-actin and microtubules in a mutually exclusive manner

The cooperation between the actin and microtubule (MT) cytoskeletons is important for cellular processes such as cell migration and muscle cell development. However, a full understanding of how this cooperation occurs has yet to be sufficiently developed. The MT plus-end tracking protein CLIP-170 has been implicated in this actin-MT coordination by associating with the actin-binding signaling protein IQGAP1 and by promoting actin polymerization through binding with formins. Thus far, the interactions of CLIP-170 with actin were assumed to be indirect. Here, we demonstrate using high-speed cosedimentation assays that CLIP-170 can bind to filamentous actin (F-actin) directly. We found that the affinity of this binding is relatively weak but strong enough to be significant in the actin-rich cortex, where actin concentrations can be extremely high. Using CLIP-170 fragments and mutants, we show that the direct CLIP-170-F-actin interaction is independent of the FEED domain, the region that mediates formin-dependent actin polymerization, and that the CLIP-170 F-actin-binding region overlaps with the MT-binding region. Consistent with these observations, in vitro competition assays indicate that CLIP-170-F-actin and CLIP-170-MT interactions are mutually exclusive. Taken together, these observations lead us to speculate that direct CLIP-170-F-actin interactions may function to reduce the stability of MTs in actin-rich regions of the cell, as previously proposed for MT end-binding protein 1.

Clinical characteristics of COVID-19 in solid organ transplant recipients following COVID-19 vaccination: A multicenter case series

BACKGROUND

Solid organ transplant recipients (SOTR) have diminished humoral immune responses to COVID-19 vaccination and higher rates of COVID-19 vaccine breakthrough infection than the general population. Little is known about COVID-19 disease severity in SOTR with COVID-19 vaccine breakthrough infections.

METHODS

Between 4/7/21 and 6/21/21 we requested case reports via the Emerging Infections Network (EIN) listserv of SARS-CoV-2 infection following COVID-19 vaccination in SOTR. Online data collection included patient demographics, dates of COVID-19 vaccine administration and clinical data related to COVID-19. We performed a descriptive analysis of patient factors and evaluated variables contributing to critical disease or need for hospitalization.

RESULTS

Sixty-six cases of SARS-CoV-2 infection after vaccination in SOTR were collected. COVID-19 occurred after the second vaccine dose in 52 (78.8%) cases of which 43 (82.7%) occurred ≥14 days post-vaccination. There were 6 deaths, 3 occurring in fully vaccinated individuals (7.0%, n = 3/43). There was no difference in the percentage of patients who recovered from COVID-19 (70.7% vs 72.2%, p = 0.90) among fully and partially vaccinated individuals. We did not identify any differences in hospitalization (60.5% vs. 55.6%, p = 0.72) or critical disease (20.9% vs. 33.3%, p = 0.30) among those who were fully vs. partially vaccinated.

CONCLUSIONS

SOTR vaccinated against COVID-19 can still develop severe, and even critical, COVID-19 disease. Two doses of mRNA COVID-19 vaccine may be insufficient to protect against severe disease and mortality in SOTR. Future studies to define correlates of protection in SOTR are needed. This article is protected by copyright. All rights reserved.

"Scentsor": A Whole-Cell Yeast Biosensor with an Olfactory Reporter for Low-Cost and Equipment-Free Detection of Pharmaceuticals

Portable and inexpensive analytical tools are required to monitor pharmaceutical quality in technology limited settings including low- and middle-income countries (LMICs). Whole cell yeast biosensors have the potential to help meet this need. However, most of the readouts for yeast biosensors require expensive equipment or reagents. To overcome this challenge, we have designed a yeast biosensor that produces a unique scent as a readout. This inducible scent biosensor, or "scentsor", does not require the user to administer additional reagents for reporter development and utilizes only the user's nose to be "read". In this Letter, we describe a scentsor that is responsive to the hormone estradiol (E2). The best estimate threshold (BET) for E2 detection with a panel of human volunteers (n = 49) is 39 nM E2 (15 nM when "non-smellers" are excluded). This concentration of E2 is sensitive enough to detect levels of E2 that would be found in dosage forms. This paper provides evidence that scent has the potential for use in portable yeast biosensors as a readout, particularly for use in LMICs.

Surgical infection prophylaxis prior to left ventricular assist device implantation: A survey of clinical practice

BACKGROUND

Short duration, antimicrobial prophylaxis that includes antistaphylococcal activity is recommended at the time of left ventricular assist device (LVAD) implantation to reduce infection-related complications. There continues to be wide variability in surgical infection prophylaxis (SIP) regimens among implantation centers. The aim of this study is to characterize current SIP regimens at different LVAD centers.

METHODS

A survey study was conducted from 26 September 2017 to 25 October 2017. Surveys were distributed electronically to LVAD coordinators and infectious diseases specialists at 75 US medical centers identified as having an LVAD program. Data collection included information about antimicrobial selection, duration, Staphylococcus aureus screening, and decolonization procedures.

RESULTS

We received 29 survey responses. The majority of surveys were completed by infectious diseases physicians (72.4% [21 out of 29]). Most responding centers reported LVAD programs established for greater than 10 years (20 out of 29 [69%]). Cardiac transplantation was performed in 28 out of 29 (96%) centers. Of centers reporting a defined SIP regimen for non-penicillin allergic patients (96% [28 out of 29]), 17.9% (5 out of 28) reported a four-drug regimen, 35.7% (10 out of 28) reported a three-drug regimen, and 46.4% (13 out of 28) reported a two-drug regimen, while no centers reported a single-drug regimen. Empiric fluconazole was common (50% [14 out of 28]) and 96.4% (27 out of 28) of regimens included vancomycin. Duration of antimicrobial prophylaxis (24 hours to 5 days), S. aureus screening, decolonization procedures, and alterations due to drug allergies varied across participating centers.

CONCLUSIONS

Our survey results indicate wide variation in SIP regimens among participating LVAD centers. These results highlight the need for studies evaluating the implications of SIP regimens, and whether clinical factors that prolong antimicrobial duration impact postoperative infection rates.

Effects of Protective American Football Headgear on Peripheral Vision Reaction Time and Visual Target Detection in Division I NCAA Football Players

The purpose of this study was to examine the effects of protective football headgear on peripheral vision reaction time and visual target detection. Twenty-five Division I NCAA football players (age = 20.5 yrs ± 0.9, height = 185.9 cm ± 6.8, body mass = 99.2 kg ± 19.2, BMI = 29.6 ± 4.5) participated. In a crossover counterbalanced study design, subjects participated in one visit with three conditions: Baseline (BL) without headgear, helmet only (HO), helmet with an eye shield (HE). Subjects completed a 1-min peripheral vision reaction time test for each condition separated by 3-min recovery periods. Tests were administered using a 64 light Dynavision D2 Visuomotor board. Target detection (total hit score) was higher during BL than HO (p < 0.001) and HE (p < 0.001). Average (p < 0.001), peak (p < 0.001), minimum (p < 0.001), and median (p < 0.001) peripheral reaction times were faster during BL than HO and HE. No significant differences were observed for any measures between HO and HE conditions (p > 0.05). Findings indicate that protective football headgear impaired reaction time to peripheral visual stimuli. The addition of an eye shield to the helmet had a small non-significant effect on reaction time and target detection. These results may hold important implications in helmet design and player safety.

Rapamycin but not acarbose decreases age-related loss of outer hair cells in the mouse Cochlea

Adding rapamycin or acarbose to diet at 9-10 months of age has been shown to significantly increase life span in both male and female UM-HET3 mice. The current study examined cochleae of male and female UM-HET3 mice at 22 months of age to determine if either treatment also influenced age-related loss of cochlear hair cells. A large loss of cochlear outer hair cells was observed at 22 months of age in untreated mice in both apical and basal halves of the cochlear spiral. Addition of acarbose to diet had no significant effect on the amount of outer hair cell loss at 22 months of age or in its pattern, with large loss in both apical and basal halves. The addition of rapamycin to diet, however, significantly reduced outer hair cell loss in the basal half of the cochlea at 22 months of age when compared to untreated mice. There was no significant difference between male and female mice in any of the conditions. Age-related outer hair cell loss in the apical cochlea precedes outer hair cell loss in the base in many mouse strains. The results of the present study suggest that rapamycin but not acarbose treatment can delay age-related loss of outer hair cells at doses at which each drug increases life span.

Intraclade Variability in Toxin Production and Cytotoxicity of Bacillus cereus Group Type Strains and Dairy-Associated Isolates

While some species in the Bacillus cereus group are well-characterized human pathogens (e.g., B. anthracis and B. cereus sensu stricto), the pathogenicity of other species (e.g., B. pseudomycoides) either has not been characterized or is presently not well understood. To provide an updated characterization of the pathogenic potential of species in the B. cereus group, we classified a set of 52 isolates, including 8 type strains and 44 isolates from dairy-associated sources, into 7 phylogenetic clades and characterized them for (i) the presence of toxin genes, (ii) phenotypic characteristics used for identification, and (iii) cytotoxicity to human epithelial cells. Overall, we found that B. cereus toxin genes are broadly distributed but are not consistently present within individual species and/or clades. After growth at 37°C, isolates within a clade did not typically show a consistent cytotoxicity phenotype, except for isolates in clade VI (B. weihenstephanensis/B. mycoides), where none of the isolates were cytotoxic, and isolates in clade I (B. pseudomycoides), which consistently displayed cytotoxic activity. Importantly, our study highlights that B. pseudomycoides is cytotoxic toward human cells. Our results indicate that the detection of toxin genes does not provide a reliable approach to predict the pathogenic potential of B. cereus group isolates, as the presence of toxin genes is not always consistent with cytotoxicity phenotype. Overall, our results suggest that isolates from multiple B. cereus group clades have the potential to cause foodborne illness, although cytotoxicity is not always consistently found among isolates within each clade.IMPORTANCE Despite the importance of the Bacillus cereus group as a foodborne pathogen, characterizations of the pathogenic potential of all B. cereus group species were lacking. We show here that B. pseudomycoides (clade I), which has been considered a harmless environmental microorganism, produces toxins and exhibits a phenotype consistent with the production of pore-forming toxins. Furthermore, B. mycoides/B. weihenstephanensis isolates (clade VI) did not show cytotoxicity when grown at 37°C, despite carrying multiple toxin genes. Overall, we show that the current standard methods to characterize B. cereus group isolates and to detect the presence of toxin genes are not reliable indicators of species, phylogenetic clades, or an isolate's cytotoxic capacity, suggesting that novel methods are still needed for differentiating pathogenic from nonpathogenic species within the B. cereus group. Our results also contribute data that are necessary to facilitate risk assessments and a better understanding as to which B. cereus group species are likely to cause foodborne illness.

Day-Case Surgery: Enhanced Recovery with Flumazenil

In an open, randomized, parallel group study of 84 adult patients undergoing elective day-case urological surgery the specific benzodiazepine antagonist flumazenil was shown to reverse effectively subjective postoperative sedation due to midazolam and enabled 83% of patients to recover and be ready for potential discharge within 15 min of surgery (control group 24% p less than 0.001). The significantly shorter recovery time has benefits in terms of increased patient cooperation and reduced demands on postoperative nursing care. The implications of these findings for day-case surgery are discussed.

Outpatient Clinic: Where is the Delay?

In outpatient clinics, consultation times are often eroded by extraneous activities. We measured the components of each outpatient episode in 167 patients attending a general urology follow-up clinic. 41% of time in the clinic was spent away from the patient—administration 17%, disturbances 15%, finding results 9%. The inefficiencies had changed little since a study in the same setting thirteen years earlier. Since then, parallel nurse-practitioner-run clinics have been introduced in the hope of giving consultants longer with the patient; however, time with each patient is now 4.8 min compared with a previous 7.6 min. The most easily addressed inefficiencies are those relating to missing information, such as radiology reports.

Interactions between Tau and Different Conformations of Tubulin: Implications for Tau Function and Mechanism

Tau is a multifaceted neuronal protein that stabilizes microtubules (MTs), but the mechanism of this activity remains poorly understood. Questions include whether Tau binds MTs laterally or longitudinally and whether Tau's binding affinity depends on the nucleotide state of tubulin. We observed that Tau binds tightly to Dolastatin-10 tubulin rings and promotes the formation of Dolastatin-10 ring stacks, implying that Tau can crosslink MT protofilaments laterally. In addition, we found that Tau prefers GDP-like tubulin conformations, which implies that Tau binding to the MT surface is biased away from the dynamic GTP-rich MT tip. To investigate the potential impact of these Tau activities on MT stabilization, we incorporated them into our previously developed dimer-scale computational model of MT dynamics. We found that lateral crosslinking activities have a much greater effect on MT stability than do longitudinal crosslinking activities, and that introducing a bias toward GDP tubulin has little impact on the observed MT stabilization. To address the question of why Tau is GDP-tubulin-biased, we tested whether Tau might affect MT binding of the +TIP EB1. We confirmed recent reports that Tau binds directly to EB1 and that Tau competes with EB1 for MT binding. Our results lead to a conceptual model where Tau stabilizes the MT lattice by strengthening lateral interactions between protofilaments. We propose that Tau's GDP preference allows the cell to independently regulate the dynamics of the MT tip and the stability of the lattice.

Bacillus wiedmannii sp. nov., a psychrotolerant and cytotoxic Bacillus cereus group species isolated from dairy foods and dairy environments

A facultatively anaerobic, spore-forming Bacillus strain, FSL W8-0169T, collected from raw milk stored in a silo at a dairy powder processing plant in the north-eastern USA was initially identified as a Bacillus cereus group species based on a partial sequence of the rpoB gene and 16S rRNA gene sequence. Analysis of core genome single nucleotide polymorphisms clustered this strain separately from known B. cereus group species. Pairwise average nucleotide identity blast values obtained for FSL W8-0169T compared to the type strains of existing B. cereus group species were <95 % and predicted DNA-DNA hybridization values were <70 %, suggesting that this strain represents a novel B. cereus group species. We characterized 10 additional strains with the same or closely related rpoB allelic type, by whole genome sequencing and phenotypic analyses. Phenotypic characterization identified a higher content of iso-C16 : 0 fatty acid and the combined inability to ferment sucrose or to hydrolyse arginine as the key characteristics differentiating FSL W8-0169T from other B. cereus group species. FSL W8-0169T is psychrotolerant, produces haemolysin BL and non-haemolytic enterotoxin, and is cytotoxic in a HeLa cell model. The name Bacillus wiedmannii sp. nov. is proposed for the novel species represented by the type strain FSL W8-0169T (=DSM 102050T=LMG 29269T).

Production of hemolysin BL by Bacillus cereus group isolates of dairy origin is associated with whole-genome phylogenetic clade

BACKGROUND

Bacillus cereus group isolates that produce diarrheal or emetic toxins are frequently isolated from raw milk and, in spore form, can survive pasteurization. Several species within the B. cereus group are closely related and cannot be reliably differentiated by established taxonomical criteria. While B. cereus is traditionally recognized as the principal causative agent of foodborne disease in this group, there is a need to better understand the distribution and expression of different toxin and virulence genes among B. cereus group food isolates to facilitate reliable characterization that allows for assessment of the likelihood of a given isolate to cause a foodborne disease.

RESULTS

We performed whole genome sequencing of 22 B. cereus group dairy isolates, which represented considerable genetic diversity not covered by other isolates characterized to date. Maximum likelihood analysis of these genomes along with 47 reference genomes representing eight validly published species revealed nine phylogenetic clades. Three of these clades were represented by a single species (B. toyonensis -clade V, B. weihenstephanensis - clade VI, B. cytotoxicus - VII), one by two dairy-associated isolates (clade II; representing a putative new species), one by two species (B. mycoides, B. pseudomycoides - clade I) and four by three species (B. cereus, B. thuringiensis, B. anthracis - clades III-a, b, c and IV). Homologues of genes encoding a principal diarrheal enterotoxin (hemolysin BL) were distributed across all, except the B. cytotoxicus clade. Using a lateral flow immunoassay, hemolysin BL was detected in 13 out of 18 isolates that carried hblACD genes. Isolates from clade III-c (which included B. cereus and B. thuringiensis) consistently did not carry hblACD and did not produce hemolysin BL. Isolates from clade IV (B. cereus, B. thuringiensis) consistently carried hblACD and produced hemolysin BL. Compared to others, clade IV was significantly (p = 0.0001) more likely to produce this toxin. Isolates from clade VI (B. weihenstephanensis) carried hblACD homologues, but did not produce hemolysin BL, possibly due to amino acid substitutions in different toxin-encoding genes.

CONCLUSIONS

Our results demonstrate that production of diarrheal enterotoxin hemolysin BL is neither inclusive nor exclusive to B. cereus sensu stricto, and that phylogenetic classification of isolates may be better than taxonomic identification for assessment of B. cereus group isolates risk for causing a diarrheal foodborne disease.

Cellular Proliferation in Canine Cutaneous Mast Cell Tumors: Associations with c-KIT and Its Role in Prognostication

Canine cutaneous mast cell tumor (MCT) is a common neoplastic disease in dogs. Due to the prevalence of canine MCTs and the variable biologic behavior of this disease, accurate prognostication and a thorough understanding of MCT biology are critical for the treatment of this disease. The goals of this study were to evaluate and compare the utility of the proliferation markers Ki67, proliferating cell nuclear antigen (PCNA), and argyrophilic nucleolar organizing region (AgNOR) as independent prognostic markers for canine MCTs and to evaluate the use of these markers in combination, as each marker assesses different aspects of cellular proliferation. An additional goal of this study was to evaluate the associations between cellular proliferation and c-KIT mutations and between cellular proliferation and aberrant KIT protein localization in canine MCTs. Fifty-six MCTs treated with surgical excision alone were included in this study. Each MCT was evaluated for Ki67 expression, PCNA expression, and KIT protein localization using immunohistochemistry; for AgNOR counts using histochemical staining; and for the presence of internal tandem duplication c-KIT mutations using polymerase chain reaction amplification. In this study, increased Ki67 and AgNOR counts were both associated with significantly decreased survival. On the basis of these results, we recommend that the evaluation of cellular proliferation, including evaluations of both Ki67 expression and AgNORs, should be routinely used in the prognostication of canine MCTs. Additionally, the results of this study show that MCTs with aberrant KIT protein localization or internal tandem duplication c-KIT mutations are associated with increased cellular proliferation, further suggesting a role for c-KIT in the progression of canine MCTs.

High quality draft genomes of the Mycoplasma mycoides subsp. mycoides challenge strains Afadé and B237

Members of the Mycoplasma mycoides cluster' represent important livestock pathogens worldwide. Mycoplasma mycoides subsp. mycoides is the etiologic agent of contagious bovine pleuropneumonia (CBPP), which is still endemic in many parts of Africa. We report the genome sequences and annotation of two frequently used challenge strains of Mycoplasma mycoides subsp. mycoides, Afadé and B237. The information provided will enable downstream 'omics' applications such as proteomics, transcriptomics and reverse vaccinology approaches. Despite the absence of Mycoplasma pneumoniae like cyto-adhesion encoding genes, the two strains showed the presence of protrusions. This phenotype is likely encoded by another set of genes.

Galactofuranose in Mycoplasma mycoides is important for membrane integrity and conceals adhesins but does not contribute to serum resistance

Mycoplasma mycoides subsp. capri (Mmc) and subsp. mycoides (Mmm) are important ruminant pathogens worldwide causing diseases such as pleuropneumonia, mastitis and septicaemia. They express galactofuranose residues on their surface, but their role in pathogenesis has not yet been determined. The M. mycoides genomes contain up to several copies of the glf gene, which encodes an enzyme catalysing the last step in the synthesis of galactofuranose. We generated a deletion of the glf gene in a strain of Mmc using genome transplantation and tandem repeat endonuclease coupled cleavage (TREC) with yeast as an intermediary host for the genome editing. As expected, the resulting YCp1.1-Δglf strain did not produce the galactofuranose-containing glycans as shown by immunoblots and immuno-electronmicroscopy employing a galactofuranose specific monoclonal antibody. The mutant lacking galactofuranose exhibited a decreased growth rate and a significantly enhanced adhesion to small ruminant cells. The mutant was also 'leaking' as revealed by a β-galactosidase-based assay employing a membrane impermeable substrate. These findings indicate that galactofuranose-containing polysaccharides conceal adhesins and are important for membrane integrity. Unexpectedly, the mutant strain showed increased serum resistance.

A Preliminary Study of Clinical Abbreviation Disambiguation in Real Time

OBJECTIVE

To save time, healthcare providers frequently use abbreviations while authoring clinical documents. Nevertheless, abbreviations that authors deem unambiguous often confuse other readers, including clinicians, patients, and natural language processing (NLP) systems. Most current clinical NLP systems "post-process" notes long after clinicians enter them into electronic health record systems (EHRs). Such post-processing cannot guarantee 100% accuracy in abbreviation identification and disambiguation, since multiple alternative interpretations exist.

METHODS

Authors describe a prototype system for real-time Clinical Abbreviation Recognition and Disambiguation (rCARD) - i.e., a system that interacts with authors during note generation to verify correct abbreviation senses. The rCARD system design anticipates future integration with web-based clinical documentation systems to improve quality of healthcare records. When clinicians enter documents, rCARD will automatically recognize each abbreviation. For abbreviations with multiple possible senses, rCARD will show a ranked list of possible meanings with the best predicted sense at the top. The prototype application embodies three word sense disambiguation (WSD) methods to predict the correct senses of abbreviations. We then conducted three experments to evaluate rCARD, including 1) a performance evaluation of different WSD methods; 2) a time evaluation of real-time WSD methods; and 3) a user study of typing clinical sentences with abbreviations using rCARD.

RESULTS

Using 4,721 sentences containing 25 commonly observed, highly ambiguous clinical abbreviations, our evaluation showed that the best profile-based method implemented in rCARD achieved a reasonable WSD accuracy of 88.8% (comparable to SVM - 89.5%) and the cost of time for the different WSD methods are also acceptable (ranging from 0.630 to 1.649 milliseconds within the same network). The preliminary user study also showed that the extra time costs by rCARD were about 5% of total document entry time and users did not feel a significant delay when using rCARD for clinical document entry.

CONCLUSION

The study indicates that it is feasible to integrate a real-time, NLP-enabled abbreviation recognition and disambiguation module with clinical documentation systems.

Histoplasmosis complicating tumor necrosis factor-α blocker therapy: a retrospective analysis of 98 cases

BACKGROUND

Histoplasmosis may complicate tumor necrosis factor (TNF)-α blocker therapy. Published case series provide limited guidance on disease management. We sought to determine the need for long-term antifungal therapy and the safety of resuming TNF-α blocker therapy after successful treatment of histoplasmosis.

METHODS

We conducted a multicenter retrospective review of 98 patients diagnosed with histoplasmosis between January 2000 and June 2011. Multivariate logistic regression was used to evaluate risk factors for severe disease.

RESULTS

The most commonly used biologic agent was infliximab (67.3%). Concomitant corticosteroid use (odds ratio [OR], 3.94 [95% confidence interval {CI}, 1.06-14.60]) and higher urine Histoplasma antigen levels (OR, 1.14 [95% CI, 1.03-1.25]) were found to be independent predictors of severe disease. Forty-six (47.4%) patients were initially treated with an amphotericin B formulation for a median duration of 2 weeks. Azole treatment was given for a median of 12 months. TNF-α blocker therapy was initially discontinued in 95 of 98 (96.9%) patients and later resumed in 25 of 74 (33.8%) patients at a median of 12 months (range, 1-69 months). The recurrence rate was 3.2% at a median follow-up period of 32 months. Of the 3 patients with recurrence, 2 had restarted TNF-α blocker therapy, 1 of whom died. Mortality rate was 3.2%.

CONCLUSIONS

In this study, disease outcomes were generally favorable. Discontinuation of antifungal treatment after clinical response and an appropriate duration of therapy, probably at least 12 months, appears safe if pharmacologic immunosuppression has been held. Resumption of TNF-α blocker therapy also appears safe, assuming that the initial antifungal therapy was administered for 12 months.

Age-related changes in auditory nerve-inner hair cell connections, hair cell numbers, auditory brain stem response and gap detection in UM-HET4 mice

This study compared the timing of appearance of three components of age-related hearing loss that determine the pattern and severity of presbycusis: the functional and structural pathologies of sensory cells and neurons and changes in gap detection (GD), the latter as an indicator of auditory temporal processing. Using UM-HET4 mice, genetically heterogeneous mice derived from four inbred strains, we studied the integrity of inner and outer hair cells by position along the cochlear spiral, inner hair cell-auditory nerve connections, spiral ganglion neurons (SGN), and determined auditory thresholds, as well as pre-pulse and gap inhibition of the acoustic startle reflex (ASR). Comparisons were made between mice of 5-7, 22-24 and 27-29 months of age. There was individual variability among mice in the onset and extent of age-related auditory pathology. At 22-24 months of age a moderate to large loss of outer hair cells was restricted to the apical third of the cochlea and threshold shifts in the auditory brain stem response were minimal. There was also a large and significant loss of inner hair cell-auditory nerve connections and a significant reduction in GD. The expression of Ntf3 in the cochlea was significantly reduced. At 27-29 months of age there was no further change in the mean number of synaptic connections per inner hair cell or in GD, but a moderate to large loss of outer hair cells was found across all cochlear turns as well as significantly increased ABR threshold shifts at 4, 12, 24 and 48 kHz. A statistical analysis of correlations on an individual animal basis revealed that neither the hair cell loss nor the ABR threshold shifts correlated with loss of GD or with the loss of connections, consistent with independent pathological mechanisms.

Management practices and major infections after cardiac surgery

BACKGROUND

Infections are the most common noncardiac complication after cardiac surgery, but their incidence across a broad range of operations, as well as the management factors that shape infection risk, remain unknown.

OBJECTIVES

This study sought to prospectively examine the frequency of post-operative infections and associated mortality, and modifiable management practices predictive of infections within 65 days from cardiac surgery.

METHODS

This study enrolled 5,158 patients and analyzed independently adjudicated infections using a competing risk model (with death as the competing event).

RESULTS

Nearly 5% of patients experienced major infections. Baseline characteristics associated with increased infection risk included chronic lung disease (hazard ratio [HR]: 1.66; 95% confidence interval [CI]: 1.21 to 2.26), heart failure (HR: 1.47; 95% CI: 1.11 to 1.95), and longer surgery (HR: 1.31; 95% CI: 1.21 to 1.41). Practices associated with reduced infection risk included prophylaxis with second-generation cephalosporins (HR: 0.70; 95% CI: 0.52 to 0.94), whereas post-operative antibiotic duration >48 h (HR: 1.92; 95% CI: 1.28 to 2.88), stress hyperglycemia (HR: 1.32; 95% CI: 1.01 to 1.73); intubation time of 24 to 48 h (HR: 1.49; 95% CI: 1.04 to 2.14); and ventilation >48 h (HR: 2.45; 95% CI: 1.66 to 3.63) were associated with increased risk. HRs for infection were similar with either <24 h or <48 h of antibiotic prophylaxis. There was a significant but differential effect of transfusion by surgery type (excluding left ventricular assist device procedures/transplant) (HR: 1.13; 95% CI: 1.07 to 1.20). Major infections substantially increased mortality (HR: 10.02; 95% CI: 6.12 to 16.39).

CONCLUSIONS

Major infections dramatically affect survival and readmissions. Second-generation cephalosporins were strongly associated with reduced major infection risk, but optimal duration of antibiotic prophylaxis requires further study. Given practice variations, considerable opportunities exist for improving outcomes and preventing readmissions. (Management Practices and Risk of Infection Following Cardiac Surgery; NCT01089712).

A novel, privacy-preserving cryptographic approach for sharing sequencing data

OBJECTIVE

DNA samples are often processed and sequenced in facilities external to the point of collection. These samples are routinely labeled with patient identifiers or pseudonyms, allowing for potential linkage to identity and private clinical information if intercepted during transmission. We present a cryptographic scheme to securely transmit externally generated sequence data which does not require any patient identifiers, public key infrastructure, or the transmission of passwords.

MATERIALS AND METHODS

This novel encryption scheme cryptographically protects participant sequence data using a shared secret key that is derived from a unique subset of an individual's genetic sequence. This scheme requires access to a subset of an individual's genetic sequence to acquire full access to the transmitted sequence data, which helps to prevent sample mismatch.

RESULTS

We validate that the proposed encryption scheme is robust to sequencing errors, population uniqueness, and sibling disambiguation, and provides sufficient cryptographic key space.

DISCUSSION

Access to a set of an individual's genotypes and a mutually agreed cryptographic seed is needed to unlock the full sequence, which provides additional sample authentication and authorization security. We present modest fixed and marginal costs to implement this transmission architecture.

CONCLUSIONS

It is possible for genomics researchers who sequence participant samples externally to protect the transmission of sequence data using unique features of an individual's genetic sequence.

50 years of informatics research on decision support: what's next

OBJECTIVES

To reflect on the history, status, and future trends of decision support in health and biomedical informatics. To highlight the new challenges posed by the complexity and diversity of genomic and clinical domains. To examine the emerging paradigms for supporting cost-effective, personalized decision making.

METHODS

A group of international experts in health and biomedical informatics presented their views and discussed the challenges and issues on decision support at the Methods of Information in Medicine 50th anniversary symposium. The experts were invited to write short articles summarizing their thoughts and positions after the symposium.

RESULTS AND CONCLUSIONS

The challenges posed by the complexity and diversity of the domain knowledge, system infrastructure, and usage pattern are highlighted. New requirements and computational paradigms for representing, using, and acquiring biomedical knowledge and healthcare protocols are proposed. The underlying common themes identified for developing next-generation decision support include incorporating lessons from history, uniform vocabularies, integrative interfaces, contextualized decisions, personalized recommendations, and adaptive solutions.

A history of the INTERNIST-1 and Quick Medical Reference (QMR) computer-assisted diagnosis projects, with lessons learned

The INTERNIST-1/Quick Medical Reference (QMR) diagnostic decision support project spans four decades, from 1971-onward. This paper describes the history of the project and details insights gained of relevance to the general clinical and informatics communities.

Design of aging intervention studies: the NIA interventions testing program

The field of biogerontology has made great strides towards understanding the biological processes underlying aging, and the time is ripe to look towards applying this knowledge to the pursuit of aging interventions. Identification of safe, inexpensive, and non-invasive interventions that slow the aging process and promote healthy aging could have a significant impact on quality of life and health care expenditures for the aged. While there is a plethora of supplements and interventions on the market that purport to slow aging, the evidence to validate such claims is generally lacking. Here we describe the development of an aging interventions testing program funded by the National Institute on Aging (NIA) to test candidate interventions in a model system. The development of this program highlights the challenges of long-term intervention studies and provides approaches to cope with the stringent requirements of a multi-site testing program.

Characterization of uterine granular cell tumors in B6C3F1 mice: a histomorphologic, immunohistochemical, and ultrastructural study

The granular cell tumor is most often a benign neoplasm of uncertain origin. Four uterine granular cell tumors in control and treated female B6C3F1 mice were identified in chronic studies at the National Toxicology Program. Two tumors occurred in untreated control animals and 2 in treated animals receiving different compounds. Tissue sections were evaluated histologically and stained with hematoxylin and eosin, periodic acid-Schiff with diastase resistance, Masson's trichrome, toluidine blue, phosphotungstic acid-hematoxylin, and stained immunohistochemically with a panel of antibodies to muscle (desmin, alpha smooth muscle actin), neural (S-100, neuron specific enolase), epithelial (wide-spectrum cytokeratin), and macrophage (F4/80) markers. The main histomorphologic feature of tumor cells was the presence of abundant cytoplasmic eosinophilic granules that stained positive for periodic acid-Schiff with diastase resistance. Tumors varied in appearance and were comprised of sheets and nests of round to polygonal cells with distinct borders. Nuclei were hyperchromatic, pleomorphic, and centrally to eccentrically located and often contained single nucleoli. Occasional multinucleated giant cells were observed. Tumors were pale pink and homogeneous with trichrome stain and negative with toluidine blue. Three tumors had positive to weakly positive immunoreactivity for desmin, and 1 was positive for alpha smooth muscle actin. Expression of S-100, wide-spectrum cytokeratin, and neuron-specific enolase was negative for all tumors. Ultrastructurally, prominent electron-dense cytoplasmic granules were abundant and contained secondary lysosomes with heterogeneous lysosomal contents. The characteristics of these uterine granular cell tumors were suggestive of a myogenic origin.

Quantitation of functional T cells by limiting dilution

Culturing by limiting dilution (LD) can be used to estimate the proportion of T cells in a cell preparation which can respond to an activating stimulus to produce interleukin 2 or to generate cytotoxic T lymphocyte (CTL) activity. In the first basic protocol, IL-2-producing murine T cells are measured following stimulation by the mitogen Con A. This protocol can be modified as described in the first alternate protocol to quantitate responses to alloantigens, anti-CD3 antibody, protein antigens such as keyhole limpet hemocyanin (KLH), and viruses. The second alternate protocol provides a modification for using human responder cells. The second basic protocol is used for estimating the proportion of cells that can generate a clone of cytotoxic effector cells when stimulated by Con A with the addition of IL-2.

Predictors of success in surgical ligation of painful varicocele

INTRODUCTION

Surgical ligation is used in the treatment of painful varicocele. We conducted this retrospective study to establish the effectiveness of varicocele ligation for the treatment of pain and to examine the factors that might predict outcomes.

PATIENTS AND METHODS

Eighty-three patients underwent varicocele ligation for pain during the study period. Review of medical records and postal questionnaires were used to document patient age, grade and location of varicocele, duration and quality of pain, surgical approach, complications and the resolution of pain.

RESULTS

Follow-up was available for 68 (82%) patients. In 76.5% patients there was marked or complete resolution of pain and 14 had partial resolution. Only 9% patients had persistent pain and 1.5% patient reported worsening pain. The quality of pain, dull ache or dragging, was the only factor that correlated with the resolution of pain following surgery.

CONCLUSIONS

Surgical ligation is an effective treatment for the painful varicocele. The quality of pain at presentation may predict outcomes in selected patients.

Older donor livers show early severe histological activity, fibrosis, and graft failure after liver transplantation for hepatitis C

BACKGROUND

In hepatitis C virus (HCV)-positive liver transplant recipients, infection of the allograft and recurrent liver disease are important problems. Increased donor age has emerged as an important variable affecting patient and graft survival; however, specific age cutoffs and risk ratios for poor histologic outcomes and graft survival are not clear.

METHODS

A longitudinal database of all HCV-positive patients transplanted at our center during an 11-year period was used to identify 111 patients who received 124 liver transplants. Graft survival and histological endpoints (severe activity and fibrosis) of HCV infection in the allografts were compared as a function of donor age at transplantation.

RESULTS

By Kaplan-Meier analyses, older allografts showed earlier failure and decreased time to severe histological activity and fibrosis as compared with allografts from younger donors. By Cox proportional hazards analysis, older allografts were at greater risk for all severe histologic features and decreased graft survival as compared with younger allografts (P< or =0.02 for all outcomes). Analysis of donor age as a dichotomous variable showed that donors greater than 60 yr were at high risk for deleterious histologic outcomes and graft failure. An age cutoff of 60 yr showed a sensitivity of 94% and specificity of 67% for worse graft survival by receiver operating characteristics curve.

CONCLUSIONS

Advanced donor age is associated with more aggressive recurrent HCV and early allograft failure in HCV-positive liver transplant recipients. Consideration of donor age is important for decisions regarding patient selection, antiviral therapy, and organ allocation.

Care provider order entry (CPOE): a perspective on factors leading to success or to failure

OBJECTIVE

Authors provide a perspective on factors leading to successful care provider order entry (CPOE) implementations.

METHODS

Viewpoint of authors supported by background literature review.

RESULTS

Authors review both benefits and challenges related to CPOE implementation using three guiding principles: (1) a clinical approach to clinical systems, which claims that CPOE implementation is analogous to a "good" clinician delivering care to a patient; (2) a commitment to quality, which advocates that no compromises should be made in implementing system functionality and clinical system content - the highest objective for CPOE implementation is to provide better quality of care and increased safety for patients; (3) a commitment to fairness, as evidenced by respect for individuals and support of local autonomy, which advocates for minimizing disruptions to clinician-users' workflows, and adequate local control over CPOE system design and evolution, including clinical content management.

CONCLUSIONS

Past experiences with CPOE implementation can inform future installation attempts. Sociocultural factors dominate in determining the success of implementation, and should govern technical factors.

Atmospheric-pressure ionization studies and field dependence of ion mobilities of isomeric hydrocarbons using a miniature differential mobility spectrometer

The ionization pathways and ion mobility were determined for sets of structural isomeric and stereoisomeric non-polar hydrocarbons (saturated and unsaturated cyclic hydrocarbons and aromatic hydrocarbons) using a novel miniature differential mobility spectrometer with atmospheric-pressure photoionization (APPI) to assess how structural and stereochemical differences influence ion formation and ion mobility. The analytical results obtained using the differential mobility spectrometry (DMS) were compared with the reduced mobility values measured using conventional time-of-flight ion mobility spectrometry (IMS) with the same ionization technique. The majority of differences in DMS ion mobility spectra observed among isomeric cyclic hydrocarbons can be explained by the formation of different product ions. Comparable differences in ion formation were also observed using conventional IMS and by investigations using the coupling of ion mobility spectrometry with mass spectrometry (APPI-IMS-MS) and APPI-MS. Using DMS, isomeric aromatic hydrocarbons can in the majority of cases be distinguished by the different behavior of product ions in the strong asymmetric radio frequency (rf) electric field of the drift channel. The different peak position of product ions depending on the electric field amplitude permits the differentiation between most of the investigated isomeric aromatics with a different constitution; this stands in contrast to conventional IMS in which comparable reduced mobility values were detected for the isomeric aromatic compounds.

The Gurnham equation in characterizing the compressibility of pharmaceutical materials

Limitations of the Heckel equation in characterizing material compression behavior have been well reported. In this work, the Gurnham equation, which was first introduced in chemical engineering, is proposed as an alternate method of evaluating the compressibility of pharmaceutical powders. The Gurnham equation was adapted for tablet compression and the estimated slope parameter c was proposed to represent material compressibility. Data from the compression of four commonly used excipients (microcrystalline cellulose, corn starch, lactose monohydrate, and dibasic calcium phosphate dihydrate) and one drug (acetaminophen) were evaluated using the Gurnham equation. Using compression data at different peak pressures, linear relationships between porosity and lnPressure of the five materials were obtained. The determined parameter c expresses the compressibility of materials. The analysis of previous experimental data, including granulations, mixtures and co-processed materials also indicates that c might be a representative parameter for material compressibility.

The expression of xenobiotic-metabolizing enzymes in human prostate and in prostate epithelial cells (PECs) derived from primary cultures

BACKGROUND

Dietary heterocyclic amines (HCAs) are carcinogenic in rodent prostate requiring activation by enzymes such as cytochrome P450 (CYP) and N-acetyltransferase (NAT).

METHODS

We investigated by Western blotting and immunohistochemistry the expression of CYP1A1, CYP1A2, and NAT1 in human prostate and in prostate epithelial cells (PECs) derived from primary cultures and tested their ability to activate the dietary carcinogen 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and its N-hydroxy metabolite (N-OH-IQ) to DNA-damaging moieties.

RESULTS

Western blotting identified CYP1A1, CYP1A2, and NAT1. Immunohistochemistry localized NAT1 to the cytoplasm of PECs. Inter-individual variation was observed in the expression levels of CYP1A1, 1A2, and NAT1 (11, 75, and 35-fold, respectively). PECs expressed CYP1A1 and NAT1 but not CYP1A2. When incubated with IQ or N-OH-IQ, PECs formed DNA adducts indicating their ability to metabolically activate these compounds.

CONCLUSIONS

Prostate cells possess the capacity to activate dietary carcinogens. PECs may provide a useful model system to study their role in prostate carcinogenesis.

Separation of ions from explosives in differential mobility spectrometry by vapor-modified drift gas

Differential mobility spectrometry (DMS) of nitro-organic explosives and related compounds exhibited the expected product ions of M- or M x NO2- from atmospheric pressure chemical ionization reactions in purified air at 100 degrees C. Peaks in the differential mobility spectra for these ions were confined to a narrow range of compensation voltages between -1 to +3 V which arose through a low dependence of mobility for the ions in electric fields at E/N values between 0 and 120 Td (1 Td = 10(-17) V cm2). The field dependence of ions, described as an alpha parameter, ranged from -0.005 to 0.02 at a separation field of 100 Td. The alpha parameter could be controlled through the addition of organic vapors into the drift gas and was increased to 0.08-0.24 with 1000 ppm of methylene chloride in the drift gas. This modification of the drift gas resulted in compensation voltages of +3 to +21 V for peaks. The improved separation of peaks was consistent with a model of ion characterization by DeltaK or Kl - Kh, where Kl is the mobility coefficient of ions clustered with vapor neutrals during the low-field portion of the separation field waveform and Kh is for the same core ion when heated and declustered during the high-field portion of waveform.

On exemplary scientific conduct regarding submission of manuscripts to biomedical informatics journals

As the Editors of leading international biomedical informatics journals, the authors report on a recent pattern of improper manuscript submissions to journals in our field. As a guide for future authors, we describe ethical and pragmatic issues related to submitting work for peer-reviewed journal publication. We propose a coordinated approach to the problem that our respective journals will follow. This Editorial is being jointly published in the following journals represented by the authors: Computer Methods and Programs in Biomedicine, International Journal of Medical Informatics, Journal of Biomedical Informatics, Journal of the American Medical Informatics Association, and Methods of Information in Medicine.

Case Report: Angioleiomyoma of the Spermatic Cord: A Rare Scrotal Mass

We report a case of angioleiomyoma of the spermatic cord. Tumours arising from the spermatic cord are rare and most of them are benign. The commonest are lipomas with sarcomas being the predominant malignant variety. This is the first reported case of angioleiomyoma of the spermatic cord.

Impact of tumour depth, tumour location and multiple synchronous masses on the prognosis of canine cutaneous mast cell tumours

The goal of this study was to determine the significance of tumour depth, tumour location and multiple synchronous tumour masses for the prognostic evaluation of canine cutaneous mast cell tumours (MCTs). The study population consisted of 100 formalin-fixed, paraffin-embedded cutaneous MCTs that had been surgically removed from 100 dogs and submitted to the Diagnostic Center of Population and Animal Health at Michigan State University between 1998 and 2001. None of the dogs had received chemotherapy or radiation therapy. For each case the following data were obtained from the referring veterinarians: sex, breed, weight, age at diagnosis, diagnostics performed, adjunct medications given at the time of surgery, tumour location, number of tumour masses, tumour recurrence (development of MCTs at the surgical site), development of additional MCTs at distant sites (outside the surgical margins), tumour duration before removal, survival time and cause of death, if applicable. Tumour depth was determined through microscopic evaluation of 5 microm sections stained with haematoxylin and eosin. Based on univariable and multivariable survival analysis, dogs with multiple synchronous cutaneous MCTs at the time of diagnosis have a worse prognosis compared with dogs with single tumours. Additional treatment beyond surgical excision alone should be considered for these animals. Older dogs and Boxers with cutaneous MCTs were at higher risk to develop additional MCTs at distant sites (outside the surgical margins), and older and male dogs with cutaneous MCTs had significantly shorter survival times. Univariable analysis also determined that dogs with cutaneous MCTs located on the head and neck had an increased risk of additional MCT development at distant sites and that sterilized dogs with cutaneous MCTs had shorter survival times. However, these findings were not confirmed by multivariable analysis. Tumour depth was of no prognostic significance for dogs with cutaneous MCTs.

Positive Serum Cryoglobulin Is Associated with Worse Outcome after Liver Transplantation for Chronic Hepatitis C

BACKGROUND

Recurrent hepatitis C virus (HCV) infection in patients after liver transplantation is an important clinical problem. Because serum cryoglobulins (CG) are known to be associated with an increased incidence of cirrhosis in nontransplant patients, the authors tested the hypothesis that CG would also predict aggressive recurrent HCV in patients after liver transplantation.

METHODS

Using a longitudinal database, the outcomes of 105 allografts transplanted into 97 HCV-positive patients from 1991 through 2002 were analyzed on the basis of CG status using a retrospective cohort design. Fifty-nine CG-negative and 38 CG-positive patients were identified. Histologic outcomes and graft survival were analyzed using Kaplan-Meier estimates and Cox univariate and multivariate analyses. Both overall survival and HCV-specific survival (non-HVC-related deaths and graft losses censored) were analyzed.

RESULTS

By Kaplan-Meier estimates, CG-positive patients showed earlier graft failure with decreased time to severe histologic activity and fibrosis as compared with CG-negative patients (P<0.05 for all outcomes). By univariate analysis, CG-positive patients had significantly higher risk ratios for shortened HCV-specific graft survival, severe activity-free survival, and severe fibrosis-free survival as compared with CG-negative patients (P<0.05 for all outcomes). In the multivariate model, CG was an independent predictor for severe activity-free, severe fibrosis-free, and HCV-specific graft survival (P<0.05 for all outcomes).

CONCLUSIONS

CG-positivity is associated with severe recurrent HCV disease in liver transplant recipients.

The cost of chronic stress: impacts of a nonhabituating stress response on metabolic variables and swimming performance in sturgeon

Metabolic scope for activity (MSA) and critical swimming velocity (U(crit)) were measured in green sturgeon exposed to two stressors daily for 28 consecutive days. The results were compared with unstressed fish in an effort to measure the "cost" of chronic stress. Chronic stress was simulated by exposing fish to a randomized order of acute stressors: a 5-min chasing stressor, a 10-min water depth reduction stressor, or a 5-min confinement stressor. The acute cortisol response to each stressor was initially determined, and the maintenance of that response was verified in 7-d intervals during the chronic stress regime. Exposure to the chronic stress regime resulted in a 25% reduction of MSA caused by significantly increased maintenance metabolic rate (0.27+/-0.01 vs. 0.19+/-0.02 mg O(2) h(-1) g(-1), chronic and control fish, respectively) but did not affect the U(crit) of sturgeon. In addition, a 50% reduction in liver glycogen levels and a twofold increase of resting plasma glucose levels were measured in chronically stressed fish. We conclude that our chronic stress regime resulted in a significant maintenance cost to green sturgeon, possibly because of their inability to habituate to the stressors, but did not decrease their swimming performance.

Standardization of a broth microdilution susceptibility testing method to determine minimum inhibitory concentrations of aquatic bacteria

A multiple laboratory study was conducted in accordance with the standards established by the Clinical and Laboratory Standards Institute (CLSI), formerly the National Committee for Clinical Laboratory Standards (NCCLS), for the development of quality control (QC) ranges using dilution antimicrobial susceptibility testing methods for bacterial isolates from aquatic animal species. QC ranges were established for Escherichia coli ATCC 25922 and Aeromonas salmonicida subsp. salmonicida ATCC 33658 when testing at 22, 28 and 35 degrees C (E. coli only) for 10 different antimicrobial agents (ampicillin, enrofloxacin, erythromycin, florfenicol, flumequine, gentamicin, ormetoprim/sulfadimethoxine, oxolinic acid, oxytetracycline and trimethoprim/sulfamethoxazole). Minimum inhibitory concentration (MIC) QC ranges were determined using dry- and frozen-form 96-well plates and cation-adjusted Mueller-Hinton broth. These QC ranges were accepted by the CLSI/NCCLS Subcommittee on Veterinary Antimicrobial Susceptibility Testing in January 2004. This broth microdilution testing method represents the first standardized method for determining MICs of bacterial isolates whose preferred growth temperatures are below 35 degrees C. Methods and QC ranges defined in this study will enable aquatic animal disease researchers to reliably compare quantitative susceptibility testing data between laboratories, and will be used to ensure both precision and inter-laboratory harmonization.

Antibiotics on urethral catheter withdrawal: a hit and miss affair

Globally, millions of patients undergo urethral catheterization every year. Our objective was to study the current use of prophylactic antibiotics on urinary catheter withdrawal. A questionnaire (N = 300) was sent to healthcare professionals involved in the management of patients with urinary catheters (consultant microbiologists, infection control nurses, consultant urologists, specialist nurses in urology, continence advisers and consultants in the care of older people). The questionnaire asked about their use of prophylactic antibiotics on the withdrawal of a urethral catheter. Sixty percent of healthcare professionals advocated the use of antibiotics for either all or selected groups of patients. The remainder did not. The use of prophylactic antibiotics varied among different groups. Of the healthcare professionals who used antibiotics, the majority cited more than one reason for their use (prevent bacteraemia, avoid an infection in a prosthesis or urinary tract infection). The course and type of antibiotic used varied. Our study has shown diversity in practice that is of concern. At present, just over one-half of patients with urinary catheters are being given antibiotics, although there is no evidence to suggest that such an intervention confers any benefit. If benefits do not exist, these patients are being exposed to the harm of antibiotics and providers are incurring costs unnecessarily. A formal trial to address this issue is urgently needed.

Do We Need to Perform Cystoscopy on All Adults Attending Urology Centres as Outpatients?

INTRODUCTION

There has been considerable expansion in the use of flexible cystoscopy (FC) and people who can perform the procedure. Hence, there is a criticism that this procedure is being overused with no management benefit.

MATERIALS AND METHODS

We audited the use of FC in a district hospital for a period of 1 year. The results of FC for non-standard indications (other than haematuria and check cystoscopy) were analysed for their diagnostic yield.

RESULTS

Of the 1,390 FCs performed, 295 were done for non-standard indications. 46.14% of these cystoscopies had positive findings. Cancer detection rate was 6.10%. Cystoscopy altered the management in 14.08% of patients and was supportive to diagnosis and management in 32.06%.

CONCLUSION

This procedure is certainly not overused and the ever-increasing requirement of this simple procedure has serious resource implications for the National Health Service.

Oral quinolones in hospitalized patients: an evaluation of a computerized decision support intervention

OBJECTIVE

To determine whether a computerized decision support system could increase the proportion of oral quinolone antibiotic orders placed for hospitalized patients.

DESIGN

Prospective, interrupted time-series analysis.

SETTING

University hospital in the south-eastern United States.

SUBJECTS

Inpatient quinolone orders placed from 1 February 2001 to 31 January 2003.

INTERVENTION

A web-based intervention was deployed as part of an existing order entry system at a university hospital on 5 February 2002. Based on an automated query of active medication and diet orders, some users ordering intravenous quinolones were presented with a suggestion to consider choosing an oral formulation.

MAIN OUTCOME MEASURE

The proportion of inpatient quinolone orders placed for oral formulations before and after deployment of the intervention.

RESULTS

There were a total of 15 194 quinolone orders during the study period, of which 8962 (59%) were for oral forms. Orders for oral quinolones increased from 4202 (56%) before the intervention to 4760 (62%) after, without a change in total orders. In the time-series analysis, there was an overall 5.6% increase (95% CI 2.8-8.4%; P < 0.001) in weekly oral quinolone orders due to the intervention, with the greatest effect on nonintensive care medical units.

CONCLUSIONS

A web-based intervention was able to increase oral quinolone orders in hospitalized patients. This is one of the first studies to demonstrate a significant effect of a computerized intervention on dosing route within an antibiotic class. This model could be applied to other antibiotics or other drug classes with good oral bioavailability.

Differential mobility spectrometry of chlorocarbons with a micro-fabricated drift tube

Chlorocarbons were ionized through gas phase chemistry at ambient pressure in air and resultant ions were characterized using a micro-fabricated drift tube with differential mobility spectrometry (DMS). Positive and negative product ions were characterized simultaneously in a single drift tube equipped with a 3 mCi (63)Ni ion source at 50 degrees C and drift gas of air with 1 ppm moisture. Scans of compensation voltage for most chlorocarbons produced differential mobility spectra with Cl(-) as the sole product ion and a few chlorocarbons produced adduct ions, M (.-) Cl(-). Detection limits were approximately 20-80 pg for gas chromatography-DMS measurements. Chlorocarbons also yielded positive ions through chemical ionization in air and differential mobility spectra showed peaks with characteristic compensation voltages for each substance. Field dependence of mobility was determined for positive and negative ions of each substance and confirmed characteristic behavior for each ion. A DMS analyzer with a membrane inlet was used to continuously monitor effluent from columns of bentonite or synthetic silica beads to determine breakthrough volumes of individual chlorocarbons. These findings suggest a potential of DMS for monitoring subsurface environments either on site or perhaps in situ.